Publications scientifique dans le domaine des technologies du 05-2012

» “Erratum: “Polarization engineered 1-dimensional electron gas arrays” [J. Appl. Phys. 111, 043715 (2012)]”

Résumé:

Auteurs: Nath, Digbijoy N.;Park, Pil Sung;Esposto, Michele;Brown, David;Keller, Stacia;Mishra, Umesh K.;Rajan, Siddharth;

Apparue dans: Journal of Applied Physics

Date publication: 05.-2012, volume: 111, issue:9, pages: 099901 - 099901-1

Editeur: IEEE

» “The Whole Is More Than the Sum of Its Parts”—Aristotle [President's Column]

Résumé:

Auteurs: Kolias, N.;

Apparue dans: IEEE Microwave Magazine

Date publication: 05.-2012, volume: 13, issue:4, pages: 22 - 60

Editeur: IEEE

» 'Fingerprinting for food stamps' row triggers North American privacy debate

Résumé:

Auteurs:

Apparue dans: Biometric Technology Today

Date publication: 05.-2012

Editeur: Elsevier B.V.

» 0.5V bulk-driven analog building blocks

Résumé:

Auteurs:

Apparue dans: AEU - International Journal of Electronics and Communications

Date publication: 05.-2012

Editeur: Elsevier B.V.

» 1-50-MHz VHF electromagnetic sensor-interface power-attenuation detector circuit

Résumé:

Auteurs:

Apparue dans: AEU - International Journal of Electronics and Communications

Date publication: 05.-2012

Editeur: Elsevier B.V.

» 1-Bit Reconfigurable Unit Cell Based on PIN Diodes for Transmit-Array Applications in

-Band

Résumé:
An electronically reconfigurable unit cell with 1-bit phase quantization (0

/180

) is proposed for

-band linear polarization transmit arrays. It consists of two rectangular patch antennas loaded by U- and O-slots and connected by a metallized via-hole. The transmission phase is controlled using two p-i-n diode switches integrated in the O-slot. An equivalent lumped-element circuit model is implemented and compared successfully to full-wave simulations. The numerical results are validated experimentally using an ad-hoc waveguide simulator. The prototype exhibits low insertion loss (1.8 dB) with the same level for both phase states, a broad 3-dB transmission bandwidth (14.7%), a 1-dB compression point of 13–15 dBm, and a gain of 5 dBi at 9.75 GHz. The performance and simplicity of the proposed unit cell make it attractive to build electronically steerable transmit arrays in

-band.

Auteurs: Clemente, A.;Dussopt, L.;Sauleau, R.;Potier, P.;Pouliguen, P.;

Apparue dans: IEEE Transactions on Antennas and Propagation

Date publication: 05.-2012, volume: 60, issue:5, pages: 2260 - 2269

Editeur: IEEE

» 100G and Beyond Transmission Technologies for Evolving Optical Networks and Relevant Physical-Layer Issues

Résumé:
As 100-Gb/s

digital coherent systems enter commercial deployment, an effort is underway to uncover the technologies that will enable the next-generation optical fiber communication systems. We envisage that future optical transport will be software-defined, enabling flexible allocation of bandwidth resources, with dynamically adjustable per-channel data rates based on instantaneous traffic demand and quality-of-service requirements, leading to unprecedented network agility. Software-defined transponders will have the programmability to adopt various modulation formats, coding rates, and the signal bandwidth based on the transmission distance and type of fiber. Digital signal processing will become increasingly ubiquitous and sophisticated, capable of compensating all types of channel impairments, enabling advanced forward error correction coding, and performing functions previously handled poorly by optical analog hardware such as spectrum shaping and demultiplexing of optical channels.

Auteurs: Ip, E.;Ji, P.;Mateo, E.;Huang, Y.-K.;Xu, L.;Qian, D.;Bai, N.;Wang, T.;

Apparue dans: Proceedings of the IEEE

Date publication: 05.-2012, volume: 100, issue:5, pages: 1065 - 1078

Editeur: IEEE

» 19-Gb/s adaptively modulated optical OFDM transmission by separated I/Q baseband delivery using 1GHz RSOAs

Résumé:

Auteurs:

Apparue dans: Optical Fiber Technology

Date publication: 05.-2012

Editeur: Elsevier B.V.

» 2011 RFIC Symposium Mini-Special Issue Editorial

Résumé:

Auteurs: Ponchak, G. E.;

Apparue dans: IEEE Transactions on Microwave Theory and Techniques

Date publication: 05.-2012, volume: 60, issue:5, pages: 1185 - 1185

Editeur: IEEE

» 20nm Gate length Schottky MOSFETs with ultra-thin NiSi/epitaxial NiSi2 source/drain

Résumé:

Auteurs:

Apparue dans: Solid-State Electronics

Date publication: 05.-2012

Editeur: Elsevier B.V.

» 24-GHz Bandwidth-Enhanced Microstrip Array Printed on a Single-Layer Electrically-Thin Substrate for Automotive Applications

Résumé:
A 24-GHz microstrip array antenna is developed on a single-layer electrically-thin substrate to provide a cost-effective solution for automotive applications. By etching two straight slots close to and parallel with the non-radiating edges, the impedance bandwidth of a conventional rectangular microstrip patch is enhanced without affecting its radiation characteristics. To demonstrate the effectiveness of the proposed technique, an 8

8 planar array with a specified sidelobe level of 25 dB in both the

-plane and

-plane is studied and prototyped on the commercial substrate RT/duroid 5880 with a thickness of 0.25 mm. The measured impedance bandwidth for VSWR less than 2 is about 1.8 GHz, which corresponds to a relative bandwidth of 7.5%. In addition, the measured gain is 22.5 dBi at the center frequency while it is higher than 21 dBi over a frequency band of 1 GHz. Finally, the measured sidelobe level is 20 dB in the

-plane and 18 dB in the

-plane.

Auteurs: Han, L.;Wu, K.;

Apparue dans: IEEE Transactions on Antennas and Propagation

Date publication: 05.-2012, volume: 60, issue:5, pages: 2555 - 2558

Editeur: IEEE

60.6 dB THD Dual-Band Micro-Electrode Array Signal Acquisition IC

» 32.9 nV/rt Hz

Résumé:
The dual-band recording of the local-field potential (LFP, 0.1–200 Hz) and the spike potential (SP, 200 Hz–10 kHz) is important for physiological studies at the cellular level. Recent study shows that the LFP signal plays important roles in modulating many profound cellular mechanisms. Although various bio-signal acquisition circuits have been reported over the years, few designs are applicable to capture both LFP and SP signals. To record both signals accurately, acquisition circuits need low noise and good linearity in both bands. In this paper, we report the design of a dual-band acquisition IC for microelectrode array (MEA) recording. The novel design uses a continuous-time (CT) front-end with chopping to suppress the noise in the LFP band, and a discrete-time (DT) back-end to achieve good linearity. The acquisition channel is fully differential, which leads to a high common-mode rejection ratio (CMRR) and power supply rejection ratio (PSRR) without the 50 Hz injection. The design interfaces the microelectrode with a transistor gate, which has high input impedance. A prototype monolithic acquisition IC is fabricated in a 0.35

m CMOS process. It includes 16 channels and an 11 bit successive-approximation (SAR) analog-to-digital converter (ADC). Every channel acquires cellular signals up to 20

with 32.9 nV/Hz

and

nonlinearity. The good linearity effectively prevents the aliasing and mixing between the two bands. For LFP signal, the recording noise is 0.9

V$_{rm rms}$. For SP signal, the recording noise is 3.3

. The new design has high input impedance (320 M

@1 kHz), high CMRR (

110 dB) and PSRR (

110 dB). The noise-efficiency factor (NEF) of the acquisition channel is 7.6. The IC is experimented to record the field potential from cultured rat cardiomyocytes in-vitro. Overall, the new MEA acquisition channel achieves the state-of-art performance.

Auteurs: Guo, J.;Yuan, J.;Huang, J.;Law, J. K.-Y.;Yeung, C.-K.;Chan, M.;

Apparue dans: IEEE Journal of Solid-State Circuits

Date publication: 05.-2012, volume: 47, issue:5, pages: 1209 - 1220

Editeur: IEEE

60.6 dB THD Dual-Band Micro-Electrode Array Signal Acquisition IC

» 32.9 nV/rt Hz

Résumé:
The dual-band recording of the local-field potential (LFP, 0.1-200 Hz) and the spike potential (SP, 200 Hz-10 kHz) is important for physiological studies at the cellular level. Recent study shows that the LFP signal plays important roles in modulating many profound cellular mechanisms. Although various bio-signal acquisition circuits have been reported over the years, few designs are applicable to capture both LFP and SP signals. To record both signals accurately, acquisition circuits need low noise and good linearity in both bands. In this paper, we report the design of a dual-band acquisition IC for microelectrode array (MEA) recording. The novel design uses a continuous-time (CT) front-end with chopping to suppress the noise in the LFP band, and a discrete-time (DT) back-end to achieve good linearity. The acquisition channel is fully differential, which leads to a high common-mode rejection ratio (CMRR) and power supply rejection ratio (PSRR) without the 50 Hz injection. The design interfaces the microelectrode with a transistor gate, which has high input impedance. A prototype monolithic acquisition IC is fabricated in a 0.35 μm CMOS process. It includes 16 channels and an 11 bit successive-approximation (SAR) analog-to-digital converter (ADC). Every channel acquires cellular signals up to 20 mV_pp with 32.9 nV/Hz^0.5 and <; 0.1% nonlinearity. The good linearity effectively prevents the aliasing and mixing between the two bands. For LFP signal, the recording noise is 0.9 μV_rms. For SP signal, the recording noise is 3.3 μV_rms. The new design has high input impedance (320 M Ω@1 kHz), high CMRR ( >; 110 dB) and PSRR ( >; 110 dB). The noise-efficiency factor (NEF) of the acquisition channel is 7.6. The IC is experimented to record the field potential from cultured rat cardiomyocytes in-vitro. Overall, the new MEA acquisition channel achieves the state-of-art performance.

Auteurs: Jing Guo;Jie Yuan;Jiageng Huang;Law, J.K.-Y.;Chi-Kong Yeung;Mansun Chan;

Apparue dans: IEEE Journal of Solid-State Circuits

Date publication: 05.-2012, volume: 47, issue:5, pages: 1209 - 1220

Editeur: IEEE

» 3D Force sensor for Biomechanical applications

Résumé:

Auteurs:

Apparue dans: Sensors and Actuators A: Physical

Date publication: 05.-2012

Editeur: Elsevier B.V.

» 3D IC floorplanning: Automating optimization settings and exploring new thermal-aware management techniques

Résumé:

Auteurs:

Apparue dans: Microelectronics Journal

Date publication: 05.-2012

Editeur: Elsevier B.V.

» 3D thermal-aware floorplanner using a MILP approximation

Résumé:

Auteurs:

Apparue dans: Microprocessors and Microsystems

Date publication: 05.-2012

Editeur: Elsevier B.V.

» 5-11GHz CMOS PA with 158.9±41ps group delay and low power using current-reused technique

Résumé:

Auteurs:

Apparue dans: AEU - International Journal of Electronics and Communications

Date publication: 05.-2012

Editeur: Elsevier B.V.

» 60-GHz AMC-Based Circularly Polarized On-Chip Antenna Using Standard 0.18-

m CMOS Technology

Résumé:
A 60-GHz artificial magnetic conductor (AMC)-based circularly polarized (CP) on-chip antenna has been designed and fabricated using standard 0.18-

m six metal-layer CMOS technology. The design consists of a wideband circularly polarized loop antenna at the top layer M6 and a novel AMC structure at the bottom layer M1. The size of the antenna including the modified AMC structure is 1.8

1.8

0.3 mm

. The circular open-loop structure is employed for antenna design because the gap within the loop can excite traveling wave current and then achieve circular polarized radiation. In addition, it is found that the bandwidth of circular polarization can be significantly increased by introducing one more inner parasitic loop. With the modified AMC structure integrated into the bottom layer, the antenna performance can be optimized and improved as more design freedom is introduced. The proposed antenna can offer a simulated peak gain of

3.7 dBi and a measured gain of

4.4 dBi, respectively, as well as simulated and measured axial ratio

bandwidth to cover from 57 to 67 GHz.

Auteurs: Bao, X.-Y.;Guo, Y.-X.;Xiong, Y.-Z.;

Apparue dans: IEEE Transactions on Antennas and Propagation

Date publication: 05.-2012, volume: 60, issue:5, pages: 2234 - 2241

Editeur: IEEE

-Norm-Based Reconstruction Algorithm for Particle Sizing

Résumé:
An l₁-norm-based reconstruction algorithm for particle sizing by using l₁-regularization is introduced in this paper. Both simulation and experiment were conducted by using a photodiode array detector to evaluate the performance of the algorithm. Particle size distributions retrieved by using Chahine, truncated singular value decomposition (TSVD), and Tikhonov algorithms were also obtained to compare with that obtained by the l₁-norm-based algorithm. In computer simulation, Rosin-Rammler, normal, and lognormal distributions of spherical particles from 7.6 to 98 in diameter were created. The measurement data of the photodiode array detector were generated based on Fraunhofer diffraction theory. Simulation results show that the l₁-norm-based algorithm not only performs better than Chahine algorithm but also performs similar to the TSVD and Tikhonov algorithms for noise-free data and is less sensitive to the noise than the TSVD and Tikhonov algorithms for noise-contaminated data. In experiment, a standard particle plate covered by particles with known size distribution, i.e., Rosin-Rammler distribution, was used. The experimental results validated the effectiveness of the l₁-norm-based algorithm.

Auteurs: Lijun Xu;Lei Xin;Zhang Cao;

Apparue dans: IEEE Transactions on Instrumentation and Measurement

Date publication: 05.-2012, volume: 61, issue:5, pages: 1395 - 1404

Editeur: IEEE

-Norm-Based Reconstruction Algorithm for Particle Sizing

Auteurs: Lijun Xu;Lei Xin;Zhang Cao;

Apparue dans: IEEE Transactions on Instrumentation and Measurement

Date publication: 05.-2012, volume: 61, issue:5, pages: 1395 - 1404

Editeur: IEEE

-Norm-Based Reconstruction Algorithm for Particle Sizing

Auteurs: Lijun Xu;Lei Xin;Zhang Cao;

Apparue dans: IEEE Transactions on Instrumentation and Measurement

Date publication: 05.-2012, volume: 61, issue:5, pages: 1395 - 1404

Editeur: IEEE

Sampled Signal Reconstruction With Causality Constraints—Part II: Theory

Résumé:
This paper provides the theoretic foundation for the design of

optimal reconstructors (also known as interpolators/holds) with a prescribed degree of causality. A compact frequency-domain solution is derived that mimics known interpolation techniques for ordinary transfer functions. In parallel, an extensive state space solution is documented. It complements the frequency-domain solution in that it constructively proves the various claims, and it also makes the solution concrete. The state space solution requires the solution of one Riccati and one Lyapunov matrix equation.

Auteurs: Meinsma, G.;Mirkin, L.;

Apparue dans: IEEE Transactions on Signal Processing

Date publication: 05.-2012, volume: 60, issue:5, pages: 2273 - 2285

Editeur: IEEE

Sampled Signal Reconstruction With Causality Constraints–Part I: Setup and Solutions

Résumé:
Pub DtlThis paper studies the problem of reconstructing an analog signal from its sampled measurements, in which the sampler (acquisition device) is given and the reconstructor (interpolator/hold) is the design parameter. We formulate this problem as an

(Wiener/Kalman filtering like) optimization problem and place the main emphasis on a systematic incorporation of causality constraints into the design procedure. Specifically, the optimization problem is solved under the constraint that the interpolation kernel is

-causal for a given

, i.e., that its impulse response is zero in the time interval

, where

is the sampling period. We present a closed-form state-space solution of the problem, whose computational complexity does not depend on

and which can be efficiently calculated and implemented.

Auteurs: Meinsma, G.;Mirkin, L.;

Apparue dans: IEEE Transactions on Signal Processing

Date publication: 05.-2012, volume: 60, issue:5, pages: 2260 - 2272

Editeur: IEEE

: An Efficient Conditional Privacy-Preserving Authentication Scheme for Vehicular Sensor Networks

Résumé:
In this paper, we propose a conditional privacy-preserving authentication scheme, called

, using pseudo-identity-based signatures for secure vehicle-to-infrastructure communications in vehicular ad hoc networks. The scheme achieves conditional privacy preservation, in which each message launched by a vehicle is mapped to a distinct pseudo-identity, and a trust authority can always retrieve the real identity of a vehicle from any pseudo-identity. In the scheme, a roadside unit (RSU) can simultaneously verify multiple received signatures, thus considerably reducing the total verification time; an RSU can simultaneously verify 2540 signed-messages/s. The time for simultaneously verifying 800 signatures in our scheme can be reduced by 18%, compared with the previous scheme.

Auteurs: Shim, K.-A.;

Apparue dans: IEEE Transactions on Vehicular Technology

Date publication: 05.-2012, volume: 61, issue:4, pages: 1874 - 1883

Editeur: IEEE

-Person Card Game Approach for Solving SET

-COVER Problem in Wireless Sensor Networks

Résumé:
Solutions to SET K-COVER problem can prolong the lifetime of wireless sensor networks (WSNs) by partitioning the sensors into sets. In this paper, a novel purely distributed method for solving SET K-COVER problem is introduced based on the game theory, in which we consider the SET K-COVER problem as a noncooperative N-person card game. The sensors in WSN are considered as the players, the cover sets chosen by N sensors are considered as the strategies, and the sensing area covered alone is considered as the payoff function for each sensor. After the gaming process, the best strategies that all of the players have chosen constitute the Nash equilibrium. In addition, we analyze the effects of the initial strategies on the gaming result and propose a solution to avoid this effect in order to obtain a better coverage performance. We also extend the optimality of Nash equilibrium in the coverage game to a more general case. Besides that, the analysis of the convergence performance and the message complexity of the proposed algorithm are also presented. Extensive simulations have been conducted to show the superiority of the proposed algorithm in convergence, robustness, and coverage, comparing with the random, K-COVER, and synchronous Nash equilibria convergence algorithms. Finally, based on the results from real experiments on both small- and large-scale WSNs, we conclude that the proposed algorithm can be applied in real application environment and is also of good performance in both convergence and coverage. Furthermore, we also provide the comparisons between results from simulations and real experiments when some practical issues are considered.

Auteurs: Qiang Wang;Wenjie Yan;Yi Shen;

Apparue dans: IEEE Transactions on Instrumentation and Measurement

Date publication: 05.-2012, volume: 61, issue:5, pages: 1522 - 1535

Editeur: IEEE

Region Incrementing Scheme in Visual Cryptography

Out of

Résumé:
Recently, Wang introduced a novel (2,

) region incrementing visual cryptographic scheme (RIVCS), which can gradually reconstruct secrets in a single image with multiple security levels. In RIVCS, the secret image is subdivided into multiple regions in such a way that any

shadow images, where

, can be used to reveal the

th region. However, Wang's scheme suffers from the incorrect-color problem, which the colors of reconstructed images may be reversed (i.e., the black and white are reversed). If the color of text is also the secret information, the incorrect-color problem will compromise the secret. Additionally, Wang's scheme is only suitable for the 2-out-of-

case, i.e.,

-RIVCS where

. In this paper, we propose a general

-RIVCS, where

and

are any integers, that is able to reveal correct colors of all regions. This paper has made three main contributions: 1) our scheme is a general

-RIVCS, where

and

can be any integers; 2) the incorrect-color problem is solved; and 3) our

- RIVCS is theoretically proven to satisfy the security and contrast conditions.

Auteurs: Yang, C.-N.;Shih, H.-W.;Wu, C.-C.;Harn, L.;

Apparue dans: IEEE Transactions on Circuits and Systems for Video Technology

Date publication: 05.-2012, volume: 22, issue:5, pages: 799 - 810

Editeur: IEEE

Résumé:
The problem of

control of switched nonlinear systems in

-normal form is investigated in this technical note where the solvability of the

control problem for individual subsystems is unnecessary. Using the generalized multiple Lyapunov functions method and the adding a power integrator technique, we design a switching law and construct continuous state feedback controllers of subsystems explicitly by a recursive design algorithm to produce global asymptotical stability and a prescribed

performance level. Multiple Lyapunov functions are exploited to reduce the conservativeness caused by adoption of a common Lyapunov function for all subsystems, which is usually required when applying the backstepping-like recursive design scheme. An example is provided to demonstrate the effectiveness of the proposed design method.

Auteurs: Long, L.;Zhao, J.;

Apparue dans: IEEE Transactions on Automatic Control

Date publication: 05.-2012, volume: 57, issue:5, pages: 1285 - 1291

Editeur: IEEE

Résumé:
The problem of

control of switched nonlinear systems in

-normal form is investigated in this technical note where the solvability of the

Auteurs: Long, L.;Zhao, J.;

Apparue dans: IEEE Transactions on Automatic Control

Date publication: 05.-2012, volume: 57, issue:5, pages: 1285 - 1291

Editeur: IEEE

Résumé:
The problem of

control of switched nonlinear systems in

-normal form is investigated in this technical note where the solvability of the

Auteurs: Long, L.;Zhao, J.;

Apparue dans: IEEE Transactions on Automatic Control

Date publication: 05.-2012, volume: 57, issue:5, pages: 1285 - 1291

Editeur: IEEE

Retention Distribution Tail in a Multitime-Program MLC SONOS Memory Due to a Random-Program-Charge-Induced Current-Path Percolation Effect

Résumé:
A

retention distribution tail in a multitime-program (MTP) silicon–oxide–nitride–oxide–silicon (SONOS) memory is investigated. We characterize a single-program-charge-loss-induced

in nor-type SONOS multilevel cells (MLCs). Our measurement shows the following: 1) A single-charge-loss-induced

exhibits an exponential distribution in magnitudes, which is attributed to a random-program-charge-induced current-path percolation effect, and 2) the standard deviation of the exponential distribution depends on the program-charge density and increases with a program

level in an MLC SONOS. In addition, we measure a

retention distribution in a 512-Mb MTP SONOS memory and observe a significant

retention tail. A numerical

retention distribution model including the percolation effect and a Poisson-distribution-based multiple-charge-loss model is developed. Our model agrees with the measured

retention distribution in a 512-Mb SONOS well. The observed

tail is realized mainly due to the percolation effect.

Auteurs: Chung, Y.-T.;Huang, T.-I.;Li, C.-W.;Chou, Y.-L.;Chiu, J.-P.;Wang, T.;Lee, M. Y.;Chen, K.-C.;Lu, C.-Y.;

Apparue dans: IEEE Transactions on Electron Devices

Date publication: 05.-2012, volume: 59, issue:5, pages: 1371 - 1376

Editeur: IEEE

Résumé:
The problem of H_∞ control of switched nonlinear systems in p-normal form is investigated in this technical note where the solvability of the H_∞ control problem for individual subsystems is unnecessary. Using the generalized multiple Lyapunov functions method and the adding a power integrator technique, we design a switching law and construct continuous state feedback controllers of subsystems explicitly by a recursive design algorithm to produce global asymptotical stability and a prescribed H_∞ performance level. Multiple Lyapunov functions are exploited to reduce the conservativeness caused by adoption of a common Lyapunov function for all subsystems, which is usually required when applying the backstepping-like recursive design scheme. An example is provided to demonstrate the effectiveness of the proposed design method.

Auteurs: Lijun Long;Jun Zhao;

Apparue dans: IEEE Transactions on Automatic Control

Date publication: 05.-2012, volume: 57, issue:5, pages: 1285 - 1291

Editeur: IEEE

Retention Distribution Tail in a Multitime-Program MLC SONOS Memory Due to a Random-Program-Charge-Induced Current-Path Percolation Effect

Résumé:
A Vt retention distribution tail in a multitime-program (MTP) silicon-oxide-nitride-oxide-silicon (SONOS) memory is investigated. We characterize a single-program-charge-loss-induced ΔVt in NOR-type SONOS multilevel cells (MLCs). Our measurement shows the following: 1) A single-charge-loss-induced ΔVt exhibits an exponential distribution in magnitudes, which is attributed to a random-program-charge-induced current-path percolation effect, and 2) the standard deviation of the exponential distribution depends on the program-charge density and increases with a program Vt level in an MLC SONOS. In addition, we measure a Vt retention distribution in a 512-Mb MTP SONOS memory and observe a significant Vt retention tail. A numerical Vt retention distribution model including the percolation effect and a Poisson-distribution-based multiple-charge-loss model is developed. Our model agrees with the measured Vt retention distribution in a 512-Mb SONOS well. The observed Vt tail is realized mainly due to the percolation effect.

Auteurs: Yueh-Ting Chung;Tzu-I Huang;Chi-Wei Li;You-Liang Chou;Jung-Piao Chiu;Tahui Wang;Lee, M.Y.;Kuang-Chao Chen;Chih-Yuan Lu;

Apparue dans: IEEE Transactions on Electron Devices

Date publication: 05.-2012, volume: 59, issue:5, pages: 1371 - 1376

Editeur: IEEE

» A 0.1–0.3 V 40–123 fJ/bit/ch On-Chip Data Link With ISI-Suppressed Bootstrapped Repeaters

Résumé:
This paper presents a 40–130 fJ/bit/ch on-chip data link design under a 0.1–0.3 V power supply. A bootstrapped CMOS repeater is proposed to drive a 10 mm on-chip bus. It features a

swing to enhance the driving capability and reduces the sub-threshold leakage current. Additionally, a precharge enhancement scheme increases the speed of the data transmission, and a leakage current reduction technique suppresses ISI jitter. A test chip is fabricated in a 55 nm SPRVT Low-K CMOS process. The measured results demonstrate that for a 10 mm on-chip bus, the achievable data rate is 0.8–100 Mbps, and the energy consumption is 40–123 fJ per bit under 0.1–0.3 V

Auteurs: Ho, Y.;Su, C.;

Apparue dans: IEEE Journal of Solid-State Circuits

Date publication: 05.-2012, volume: 47, issue:5, pages: 1242 - 1251

Editeur: IEEE

» A 0.2–2.6 GHz Wideband Noise-Reduction Gm-Boosted LNA

Résumé:
This letter presents a wideband low-noise amplifier (LNA) which utilizes

-boosted and noise-reduction techniques. The proposed DC-coupled 2-stage LNA employs an error amplifier to cancel the DC-offset voltage between the differential DC-coupled paths. The LNA is implemented in 90-nm digital CMOS technology. Within 0.2–2.6 GHz wideband applications, the LNA achieves 24 dB voltage gain, 1.9–2.9 dB NF,

3 dBm IIP3. The core power of the LNA draws 9 mA from 1 V supply voltage and occupies 0.046

Auteurs: Lee, H.-C.;Wang, C.-S.;Wang, C.-K.;

Apparue dans: IEEE Microwave and Wireless Components Letters

Date publication: 05.-2012, volume: 22, issue:5, pages: 269 - 271

Editeur: IEEE

» A 0.8–2 GHz Fully-Integrated QPLL-Timed Direct-RF-Sampling Bandpass

ADC in 0.13

Résumé:
A reconfigurable bandpass continuous-time

RF ADC tunable over the 0.8–2 GHz frequency range is presented. System- and circuit-level innovations provide low power consumption and reduced circuit complexity. The proposed architecture operates in both the first- and second-Nyquist zones to enable a wide tuning range from a fixed sampling frequency of 3.2 GHz. A fully-integrated on-chip quadrature phase-locked loop (QPLL) allows quadrature phase synchronization between a raised-cosine DAC and a quantizer. Implemented in 0.13

m CMOS the fully-integrated prototype achieves SNDR values of 50 dB, 46 dB, and 40 dB over a 1 MHz bandwidth at 796.5 MHz, 1.001 GHz and 1.924 GHz carrier frequencies, respectively, with a total power consumption of 41 mW. The measured phase noise of the QPLL is

113 dBc/Hz at an offset frequency of 1 MHz and the reference spur is

74.5 dBc. The RMS period jitter is 1.38 ps at 3.2 GHz.

Auteurs: Gupta, S.;Gangopadhyay, D.;Lakdawala, H.;Rudell, J. C.;Allstot, D. J.;

Apparue dans: IEEE Journal of Solid-State Circuits

Date publication: 05.-2012, volume: 47, issue:5, pages: 1141 - 1153

Editeur: IEEE

» A 0.8–2 GHz Fully-Integrated QPLL-Timed Direct-RF-Sampling Bandpass

ADC in 0.13

Résumé:
A reconfigurable bandpass continuous-time ΣΔ RF ADC tunable over the 0.8-2 GHz frequency range is presented. System- and circuit-level innovations provide low power consumption and reduced circuit complexity. The proposed architecture operates in both the first- and second-Nyquist zones to enable a wide tuning range from a fixed sampling frequency of 3.2 GHz. A fully-integrated on-chip quadrature phase-locked loop (QPLL) allows quadrature phase synchronization between a raised-cosine DAC and a quantizer. Implemented in 0.13 μm CMOS the fully-integrated prototype achieves SNDR values of 50 dB, 46 dB, and 40 dB over a 1 MHz bandwidth at 796.5 MHz, 1.001 GHz and 1.924 GHz carrier frequencies, respectively, with a total power consumption of 41 mW. The measured phase noise of the QPLL is -113 dBc/Hz at an offset frequency of 1 MHz and the reference spur is - 74.5 dBc. The RMS period jitter is 1.38 ps at 3.2 GHz.

Auteurs: Gupta, S.;Gangopadhyay, D.;Lakdawala, H.;Rudell, J.C.;Allstot, D.J.;

Apparue dans: IEEE Journal of Solid-State Circuits

Date publication: 05.-2012, volume: 47, issue:5, pages: 1141 - 1153

Editeur: IEEE

» A 1-V 15-Bit Audio

-ADC in 0.18

Résumé:
In this paper a 1-V supply, 15-bit

ADC design for audio applications is presented. The second order CIFB

modulator with a 3-bit internal quantizer is adopted. The design of noise transfer function (NTF) is discussed from the viewpoint of mitigating the quantization noise mixture effect. A single-capacitor summing circuit is proposed which eliminates additional amplification or deliberate reference scaling. Nonideal effect due to parasitic capacitance is discussed. With proper modulator architecture, the design of building blocks is relaxed. Low gain amplifier with high power efficiency can be adopted which saves power. The decimator is implemented with cascade subfilters. Time multiplexing of arithmetic resources is employed for low hardware cost. Fabricated in 0.18

m CMOS, the prototype ADC achieves 91.3 dB peak SNDR with 16 kHz. The modulator dissipates 190

W and the decimator consumes 170

W. The core area of the ADC is 0.5 mm

. The modulator occupies 0.3 mm

and the decimator occupies 0.2 mm

Auteurs: Liu, L.;Li, D.;Chen, L.;Ye, Y.;Wang, Z.;

Apparue dans: IEEE Transactions on Circuits and Systems I: Regular Papers

Date publication: 05.-2012, volume: 59, issue:5, pages: 915 - 925

Editeur: IEEE

» A 1-V 15-Bit Audio

-ADC in 0.18

Résumé:
In this paper a 1-V supply, 15-bit

ADC design for audio applications is presented. The second order CIFB

m CMOS, the prototype ADC achieves 91.3 dB peak SNDR with 16 kHz. The modulator dissipates 190

W and the decimator consumes 170

W. The core area of the ADC is 0.5 mm

. The modulator occupies 0.3 mm

and the decimator occupies 0.2 mm

Auteurs: Liu, L.;Li, D.;Chen, L.;Ye, Y.;Wang, Z.;

Apparue dans: IEEE Transactions on Circuits and Systems I: Regular Papers

Date publication: 05.-2012, volume: 59, issue:5, pages: 915 - 925

Editeur: IEEE

» A 1.2V, 130nm CMOS parallel continuous-time ?? ADC for OFDM UWB receivers

Résumé:

Auteurs: Graphical Abstract

Apparue dans: Microelectronics Journal

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A 10-Bit 80-MS/s Decision-Select Successive Approximation TDC in 65-nm CMOS

Résumé:
This paper presents a 10-bit 80-MS/s successive approximation time-to-digital converter (TDC) with a decision-select structure for on-chip timing measurement applications. Time-domain successive approximation is realized utilizing a relative timing difference between input and reference timings. While the successive approximation scheme allows high bit resolutions and low power consumptions, the decision-select structure enables fast bit conversions that lead to high sampling rates. The decision-select structure unrolls the successive approximation iteration loop and removes time-consuming timing estimation and adjustment procedures to minimize bit conversion times. As the successive approximation scheme relies on a binary search, exponential delay lines are adopted to achieve good power and noise performances by reducing the total number of delay stages. The proposed TDC uses only 0.048 delay stages per bit conversion. A test-chip prototype fabricated in a 65-nm CMOS technology consumes 9.6 mW at 80-MS/s and demonstrates 0.23-pJ/conversion-step figure-of merit (FOM) and 0.5-LSB single-shot precision.

Auteurs: Chung, H.;Ishikuro, H.;Kuroda, T.;

Apparue dans: IEEE Journal of Solid-State Circuits

Date publication: 05.-2012, volume: 47, issue:5, pages: 1232 - 1241

Editeur: IEEE

» A 130-nm CMOS 100-Hz–6-GHz Reconfigurable Vector Signal Analyzer and Software-Defined Receiver

Résumé:
A monolithic 100-Hz–6-GHz reconfigurable vector signal analyzer (VSA) and software-defined receiver (SDR), following a two-step up–down conversion heterodyne scheme with robustness to various wideband interference scenarios and local oscillator (LO) harmonic mixing, is presented. The 130-nm CMOS chip does not require external filters or baseband processing to reduce the effect of interferences or LO harmonics. The receiver has tunable gain from

67 to 68 dB in steps of 0.5 dB, and tunable bandwidth from 0.4 to 11 MHz in steps of 0.5 MHz. The receiver sensitivity at the maximum gain is

82 dBm. A monolithic VSA/SDR enables various commercial and military wireless solutions.

Auteurs: Goel, A.;Analui, B.;Hashemi, H.;

Apparue dans: IEEE Transactions on Microwave Theory and Techniques

Date publication: 05.-2012, volume: 60, issue:5, pages: 1375 - 1389

Editeur: IEEE

» A 14 Gbps On-/Off- Keying Modulator in GaAs HBT Technology

Résumé:
A proof of concept on-/off- keying (OOK) modulator is designed and implemented in a commercial heterojunction bipolar transistors IC process. The modulator circuit consists of an amplifier/latch structure, which is used as an OOK modulator for the first time. One of its advantages is that the topology may be implemented in both field effect transistor and bipolar technology. The measurement results correspond well with simulation and show that the modulator is capable of handling carrier frequencies up to 28 GHz, and data rates up to 14 Gbps. The isolation of the modulator in the off-state is better than 27 dB over the whole frequency range.

Auteurs: He, Z.;Swahn, T.;Li, Y.;Zirath, H.;

Apparue dans: IEEE Microwave and Wireless Components Letters

Date publication: 05.-2012, volume: 22, issue:5, pages: 272 - 274

Editeur: IEEE

» A 1V, 69-73GHz CMOS power amplifier based on improved Wilkinson power combiner

Résumé:

Auteurs:

Apparue dans: Microelectronics Journal

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A 2-D Electronically Steered Phased-Array Antenna With 2

2 Elements in LC Display Technology

2 microstrip patch antenna array, continuously variable delay lines with a novel geometry, RF feeding, and biasing networks. The expected insertion loss of the variable delay line is less than 4 dB with a maximum differential phase shift of 300

. During the measurements, the antenna is steered by applying an appropriate dc biasing in the range of 0–15 V to the variable delay lines. It is also shown that the return loss is always better than 15 dB at the operating frequency when the antenna is steered.

Auteurs: Karabey, O. H.;Gaebler, A.;Strunck, S.;Jakoby, R.;

Apparue dans: IEEE Transactions on Microwave Theory and Techniques

Date publication: 05.-2012, volume: 60, issue:5, pages: 1297 - 1306

Editeur: IEEE

» A 2-D Electronically Steered Phased-Array Antenna With 2

2 Elements in LC Display Technology

Résumé:
For the first time, a 2-D electronically steered phased-array antenna with a liquid-crystal (LC)-based variable delay line is presented. The structure, which is designed at 17.5 GHz, consists of a 2 × 2 microstrip patch antenna array, continuously variable delay lines with a novel geometry, RF feeding, and biasing networks. The expected insertion loss of the variable delay line is less than 4 dB with a maximum differential phase shift of 300°. During the measurements, the antenna is steered by applying an appropriate dc biasing in the range of 0-15 V to the variable delay lines. It is also shown that the return loss is always better than 15 dB at the operating frequency when the antenna is steered.

Auteurs: Karabey, O.H.;Gaebler, A.;Strunck, S.;Jakoby, R.;

Apparue dans: IEEE Transactions on Microwave Theory and Techniques

Date publication: 05.-2012, volume: 60, issue:5, pages: 1297 - 1306

Editeur: IEEE

» A 209–233 GHz Frequency Source in 90 nm CMOS Technology

Résumé:
This letter presents a J-band signal source based on a third harmonic generation of a differential Colpitts voltage controlled oscillator (VCO). The source covers a frequency range from 209.3 to 233.3 GHz, which corresponds to a 10.8% total tuning range. This is the widest tuning range in a J-band source signal reported to date. The VCO was fabricated using a 90 nm Mixed-Mode/RF CMOS process; it provides

output power at 228 GHz, while consuming 48 mA from a 1.8 V supply, and an estimated phase noise of

at 1 MHz offset from the carrier.

Auteurs: Khamaisi, B.;Socher, E.;

Apparue dans: IEEE Microwave and Wireless Components Letters

Date publication: 05.-2012, volume: 22, issue:5, pages: 260 - 262

Editeur: IEEE

» A 3–10 GHz, 14 Bands CMOS Frequency Synthesizer With Spurs Reduction for MB-OFDM UWB System

Résumé:
This paper presents the design of a 14 bands CMOS frequency synthesizer with spurs reduction for MB-OFDM UWB system. Based on a single phase-locked loop and two-stage frequency mixing architecture, it alleviates harmonics mixing and frequency pulling to diminish spurs generation. Also, only divide-by-2 dividers are needed in the feedback path of the PLL. Thus more precise I/Q sub-harmonics can be derived for the SSB mixer in the 14 bands carrier generation. The image spurs are suppressed below -45 dBc and improved by more than 22 dB incorporating with I/Q calibration. Implemented in a 0.18-μm CMOS technology, this chip drains 65 mA from a single 1.8 V supply. The chip size is 2.5 by 2.2 mm² providing 14 bands I/Q phases.

Auteurs: Tai-You Lu;Wei-Zen Chen;

Apparue dans: IEEE Transactions on Very Large Scale Integration Systems

Date publication: 05.-2012, volume: 20, issue:5, pages: 948 - 958

Editeur: IEEE

» A 3-DOF parallel manufacturing module and its kinematic optimization

Résumé:

Auteurs:

Apparue dans: Robotics and Computer-Integrated Manufacturing

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A 3.1–4.8-GHz IR-UWB All-Digital Pulse Generator With Variable Channel Selection in 0.13-

CMOS Technology

Résumé:
An all-digital pulse generator in a standard 0.13-

CMOS technology for communication systems using an impulse radio ultrawideband signal is presented. A delay-line-based architecture utilizing only static logic gates for pulse generation with low-power characteristic is proposed in this brief. The center frequency and the fixed bandwidth of 500 MHz of the output signal can be digitally controlled to cover three channels in the low band of UWB spectrum. Delay-based binary phase shift keying and pulse position modulation schemes are exploited at the same time to modulate transmitted signals with further improvement in spectrum characteristics. The total energy consumption is 48 pJ/pulse at 1.2-V supply voltage without static bias currents.

Auteurs: Choi, Y.;Kim, Y.;Hoang, H.;Bien, F.;

Apparue dans: IEEE Transactions on Circuits and Systems II: Express Briefs

Date publication: 05.-2012, volume: 59, issue:5, pages: 282 - 286

Editeur: IEEE

» A 3.5 GHz Spread-Spectrum Clock Generator With a Memoryless Newton-Raphson Modulation Profile

Résumé:
A frequency-locked loop (FLL) based spread-spectrum clock generator (SSCG) with a memoryless Newton-Raphson modulation profile is introduced in this paper. The SSCG uses an FLL as a main clock generator. It brings not only an area reduction to the SSCG but also the advantage of having multiple frequency deviations. A double binary-weighted DAC is proposed that modulates the frequency information of the frequency detector using a 1-1-1 MASH

modulator. The Newton-Raphson mathematical algorithm is applied to the proposed profile generator in order to generate the optimized nonlinear profile without needing any memory, resulting in a reduction in the area and the power consumption. It also makes it possible to have multiple modulation frequencies. The SSCG can support 14 frequency deviations of

to 3.5% in steps of 0.5% and three modulation frequencies of

and

. It achieved an EMI reduction of 19.14 dB with a 0.5% down spreading and a 31 kHz modulation frequency, while employing a core area of 0.076

in a 0.13-

CMOS process and consuming 23.72 mW at 3.5 GHz.

Auteurs: Sewook Hwang;Song, M.;Kwak, Y.-H.;Jung, I.;Kim, C.;

Apparue dans: IEEE Journal of Solid-State Circuits

Date publication: 05.-2012, volume: 47, issue:5, pages: 1199 - 1208

Editeur: IEEE

» A 30-MHz–2.4-GHz CMOS Receiver With Integrated RF Filter and Dynamic-Range-Scalable Energy Detector for Cognitive Radio Systems

Résumé:
A 30-MHz–2.4-GHz complementary metal oxide semiconductor (CMOS) receiver with an integrated tunable RF filter and a dynamic-range-scalable energy detector for both white-space and interference-level sensing in cognitive radio systems is reported. The second-order RF filter has only two stacked transistors, and its use, in combination with a subsequent harmonic rejection mixer, results in wideband interference rejection. The energy detector with programmable rectifiers provides dynamic-range (DR) scalability, enabling shared use for white-space/interference-level detection and automatic gain control. A prototype chip, fabricated using 90-nm CMOS technology, achieved over 42-dB harmonic rejection including 7th-order component without any external device, a 67-dB gain, a 5–8-dB noise figure, a

11-dBm in-band third-order intercept point, and a

38-dBm second-order intercept point while drawing only 25–37 mA from a 1.2-V power supply. Multi-resolution DR-scalable spectrum sensing with a 0.2–30-MHz detection bandwidth,

83-dBm minimum sensitivity, and a 29–48-dB DR was demonstrated.

Auteurs: Kitsunezuka, M.;Kodama, H.;Oshima, N.;Kunihiro, K.;Maeda, T.;Fukaishi, M.;

Apparue dans: IEEE Journal of Solid-State Circuits

Date publication: 05.-2012, volume: 47, issue:5, pages: 1084 - 1093

Editeur: IEEE

» A 5.6 GHz to 11.5 GHz DCO for Digital Dual Loop CDRs

Résumé:
A DCO is realized in 0.13

m CMOS using 4 cores for a 5.6 to 11.5 GHz octave tuning bandwidth to provide the clock for an all digital D/PLL CDR circuit. The DCO is novel in that it can track more than a 130 degree C temperature variation while the CDR maintains an error free lock to data. Each core is directly coupled to a div/2 to produce I/Q signals that a 4:1 MUX combines into a single set of 2.8 to 5.8 GHz quadrature outputs to drive the sine interpolator of the CDR. Locked to maximum data rms jitter, integrated from 1 kHz to 1 GHz is 299 fs @ 9.953 Gb/s (Sonet OC-192) from a DCO phase noise of

116 dBc/Hz at 1 MHz offset. The

gain is 190 ppm/bit with less than 2:1 variation over the full bandwidth. The combined DCO, divide by 2 and MUX current is 14 mA to 37 mA on a 1.2 V regulated supply at 25

Auteurs: Titus, W. S.;Kenney, J. G.;

Apparue dans: IEEE Journal of Solid-State Circuits

Date publication: 05.-2012, volume: 47, issue:5, pages: 1123 - 1130

Editeur: IEEE

» A 5MSps 13.25?W 8-bit SAR ADC with single-ended or differential input

Résumé:

Auteurs: Graphical Abstract

Apparue dans: Microelectronics Journal

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A 6-GHz All-Digital Fractional-

Frequency Synthesizer Using FIR-Embedded Noise Filtering Technique

Résumé:
A 6-GHz all-digital fractional-

frequency synthesizer using an FIR-embedded noise filtering technique is presented. This noise filtering technique is realized in the digital domain without multiple matched analog components. This fractional-

frequency synthesizer is fabricated in a 90-nm CMOS process, and it occupies 0.18

. Its power is 28.8 mW with a supply of 1.2 V. The measured out-of-band phase noise at an offset of half the reference frequency is improved by more than 13 dB around 6 GHz considering cancellation variations for different output frequencies.

Auteurs: Lee, I-T.;Lu, H.-Y.;Liu, S.-I.;

Apparue dans: IEEE Transactions on Circuits and Systems II: Express Briefs

Date publication: 05.-2012, volume: 59, issue:5, pages: 267 - 271

Editeur: IEEE

-Band CMOS UWB Radar Transmitter With a Bi-Phase Modulating Pulsed Oscillator

» A

Résumé:
This paper presents a

-band CMOS UWB radar transmitter with highly accurate variable delay circuits and a bi-phase modulating pulsed oscillator. The UWB radar transmitter is composed of three blocks: variable delay circuits that consist of a digital synchronized counter and a Vernier delay line (VDL), a baseband control signal generator, and a pulsed oscillator. The VDL allows a high range accuracy level of several millimeters. Asymmetric signals generated by the baseband control signal generator can control the phase of each output pulse. Because the pulsed oscillator operates only for the duration of a pulse, it has an extremely low level of DC power consumption and no LO leakage. It is fabricated with 0.13-

m CMOS technology and a chip with dimensions of 0.98 mm

0.69 mm. The output spectrum is centered at 26.0 GHz, and the pulse width is controllable from 280 to 680 ps. The peak output power is about 2 dBm.

Auteurs: Lee, S.;Kim, C.-Y.;Hong, S.;

Apparue dans: IEEE Transactions on Microwave Theory and Techniques

Date publication: 05.-2012, volume: 60, issue:5, pages: 1405 - 1412

Editeur: IEEE

-Band CMOS UWB Radar Transmitter With a Bi-Phase Modulating Pulsed Oscillator

» A

Résumé:
This paper presents a K-band CMOS UWB radar transmitter with highly accurate variable delay circuits and a bi-phase modulating pulsed oscillator. The UWB radar transmitter is composed of three blocks: variable delay circuits that consist of a digital synchronized counter and a Vernier delay line (VDL), a baseband control signal generator, and a pulsed oscillator. The VDL allows a high range accuracy level of several millimeters. Asymmetric signals generated by the baseband control signal generator can control the phase of each output pulse. Because the pulsed oscillator operates only for the duration of a pulse, it has an extremely low level of DC power consumption and no LO leakage. It is fabricated with 0.13-μm CMOS technology and a chip with dimensions of 0.98 mm × 0.69 mm. The output spectrum is centered at 26.0 GHz, and the pulse width is controllable from 280 to 680 ps. The peak output power is about 2 dBm.

Auteurs: Sungeun Lee;Choul-Young Kim;Songcheol Hong;

Apparue dans: IEEE Transactions on Microwave Theory and Techniques

Date publication: 05.-2012, volume: 60, issue:5, pages: 1405 - 1412

Editeur: IEEE

» A Batch-Authenticated and Key Agreement Framework for P2P-Based Online Social Networks

Résumé:
Online social networks (OSNs) such as Facebook and MySpace are flourishing because more and more people are using OSNs to share their interests with friends. Because security and privacy issues on OSNs are major concerns, we propose a security framework for simultaneously authenticating multiple users to improve the efficiency and security of peer-to-peer (P2P)-based OSNs. In the proposed framework, three batch authentication protocols are proposed, adopting the one-way hash function, ElGamal proxy encryption, and certificates as the underlying cryptosystems. The hash-based authentication protocol requires lower computational cost and is suitable for resource-limited devices. The proxy-based protocol is based on asymmetric encryption and can be used to exchange more information among users. The certificate-based protocol guarantees nonrepudiation of transactions by signatures. Without a centralized authentication server, the proposed framework can therefore facilitate the extension of an OSN with batched verifications. In this paper, we formally prove that the proposed batch authentication protocols are secure against both passive adversaries and impersonator attacks, can offer implicit key authentication, and require fewer messages to authenticate multiple users. We also show that our protocols can meet important security requirements, including mutual authentication, reputation, community authenticity, nonrepudiation, and flexibility. With these effective security features, our framework is appropriate for use in P2P-based OSNs.

Auteurs: Yeh, L.-Y.;Huang, Y.-L.;Joseph, A. D.;Shieh, S. W.;Tsaur, W.-J.;

Apparue dans: IEEE Transactions on Vehicular Technology

Date publication: 05.-2012, volume: 61, issue:4, pages: 1907 - 1924

Editeur: IEEE

» A Batch-Mode Active Learning Technique Based on Multiple Uncertainty for SVM Classifier

Résumé:
In this letter, we present a novel batch-mode active learning technique for solving multiclass classification problems by using the support vector machine classifier with the one-against-all architecture. The uncertainty of each unlabeled sample is measured by defining a criterion which not only considers the smallest distance to the decision hyperplanes but also takes into account the distances to other hyperplanes if the sample is within the margin of their decision boundaries. To select batch of most uncertain samples from all over the decision region, the uncertain regions of the classifiers are partitioned into multiple parts depending on the number of geometrical margins of binary classifiers passing on them. Then, a balanced number of most uncertain samples are selected from each part. To minimize the redundancy and keep the diversity among these samples, the kernel k-means clustering algorithm is applied to the set of uncertain samples, and the representative sample (medoid) from each cluster is selected for labeling. The effectiveness of the proposed method is evaluated by comparing it with other batch-mode active learning techniques existing in the literature. Experimental results on two different remote sensing data sets confirmed the effectiveness of the proposed technique.

Auteurs: Patra, S.;Bruzzone, L.;

Apparue dans: IEEE Geoscience and Remote Sensing Letters

Date publication: 05.-2012, volume: 9, issue:3, pages: 497 - 501

Editeur: IEEE

» A Bayesian approach for place recognition

Résumé:

Auteurs:

Apparue dans: Robotics and Autonomous Systems

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A Beamlet-Based Graph Structure for Path Planning Using Multiscale Information

Résumé:
Path-planning problems are fundamental in many applications, such as transportation, artificial intelligence, control of autonomous vehicles, and many more. In this paper, we consider the deterministic path-planning problem, equivalently, the single-pair shortest path problem on a given grid-like graph structure. Current commonly used algorithms in this area include the

algorithm, Dijkstra's algorithm, and their numerous variants. We propose an innovative beamlet-based graph structure for path planning that utilizes multiscale information of the environment. This information is collected via a bottom-up fusion algorithm. This new graph structure goes beyond “nearest-neighbor” connectivity, incorporating “long-distance” interactions between the nodes of the graph. Based on this new graph structure, we obtain a multiscale version of

, which is advantageous when preprocessing is allowable and feasible. Compared to the benchmark

algorithm, the use of multiscale information leads to an improvement in terms of computational complexity. Numerical experiments indicate an even more favorable behavior than the one predicted by the theoretical complexity analysis.

Auteurs: Lu, Y.;Huo, X.;Tsiotras, P.;

Apparue dans: IEEE Transactions on Automatic Control

Date publication: 05.-2012, volume: 57, issue:5, pages: 1166 - 1178

Editeur: IEEE

» A Behavioral Circuit Model of Active-Matrix Liquid Crystal Displays for Optical Response Simulation

Résumé:
We propose a behavioral circuit model to precisely predict optical responses of an active-matrix liquid crystal (LC) display (LCD) using a patterned vertical alignment (PVA) mode. To get more accurate simulation results, we propose two LC groups with different time constants for a pixel after observing the LCD pixels by using a high-speed camera. In addition, we include a time-delay concept into our behavioral model for brightening or rising transitions. We describe the behavior of the PVA-LCD by using the analog hardware description language Verilog-A. We simulate the PVA-LCD panel by importing the behavioral circuit model in the circuit simulator SmartSPICE. The simulation results of the transient optical responses show excellent matches with the measurement ones.

Auteurs: Cho, Y.;Park, C.;Kim, J.-M.;Lee, S.-H.;Lee, S.-W.;

Apparue dans: IEEE Transactions on Electron Devices

Date publication: 05.-2012, volume: 59, issue:5, pages: 1430 - 1438

Editeur: IEEE

» A Biologically Inspired Validity Measure for Comparison of Clustering Methods over Metabolic Data Sets

Résumé:
In the biological domain, clustering is based on the assumption that genes or metabolites involved in a common biological process are coexpressed/coaccumulated under the control of the same regulatory network. Thus, a detailed inspection of the grouped patterns to verify their memberships to well-known metabolic pathways could be very useful for the evaluation of clusters from a biological perspective. The aim of this work is to propose a novel approach for the comparison of clustering methods over metabolic data sets, including prior biological knowledge about the relation among elements that constitute the clusters. A way of measuring the biological significance of clustering solutions is proposed. This is addressed from the perspective of the usefulness of the clusters to identify those patterns that change in coordination and belong to common pathways of metabolic regulation. The measure summarizes in a compact way the objective analysis of clustering methods, which respects coherence and clusters distribution. It also evaluates the biological internal connections of such clusters considering common pathways. The proposed measure was tested in two biological databases using three clustering methods.

Auteurs: Stegmayer, G.;Milone, D.H.;Kamenetzky, L.;Lopez, M.G.;Carrari, F.;

Apparue dans: IEEE/ACM Transactions on Computational Biology and Bioinformatics

Date publication: 05.-2012, volume: 9, issue:3, pages: 706 - 716

Editeur: IEEE

» A Boosted Bayesian Multiresolution Classifier for Prostate Cancer Detection From Digitized Needle Biopsies

Résumé:
Diagnosis of prostate cancer (CaP) currently involves examining tissue samples for CaP presence and extent via a microscope, a time-consuming and subjective process. With the advent of digital pathology, computer-aided algorithms can now be applied to disease detection on digitized glass slides. The size of these digitized histology images (hundreds of millions of pixels) presents a formidable challenge for any computerized image analysis program. In this paper, we present a boosted Bayesian multiresolution (BBMR) system to identify regions of CaP on digital biopsy slides. Such a system would serve as an important preceding step to a Gleason grading algorithm, where the objective would be to score the invasiveness and severity of the disease. In the first step, our algorithm decomposes the whole-slide image into an image pyramid comprising multiple resolution levels. Regions identified as cancer via a Bayesian classifier at lower resolution levels are subsequently examined in greater detail at higher resolution levels, thereby allowing for rapid and efficient analysis of large images. At each resolution level, ten image features are chosen from a pool of over 900 first-order statistical, second-order co-occurrence, and Gabor filter features using an AdaBoost ensemble method. The BBMR scheme, operating on 100 images obtained from 58 patients, yielded: 1) areas under the receiver operating characteristic curve (AUC) of 0.84, 0.83, and 0.76, respectively, at the lowest, intermediate, and highest resolution levels and 2) an eightfold savings in terms of computational time compared to running the algorithm directly at full (highest) resolution. The BBMR model outperformed (in terms of AUC): 1) individual features (no ensemble) and 2) a random forest classifier ensemble obtained by bagging multiple decision tree classifiers. The apparent drop-off in AUC at higher image resolutions is due to lack of fine detail in the expert annotation of CaP and is not an artifact of the- classifier. The implicit feature selection done via the AdaBoost component of the BBMR classifier reveals that different classes and types of image features become more relevant for discriminating between CaP and benign areas at different image resolutions.

Auteurs: Doyle, S.;Feldman, M.;Tomaszewski, J.;Madabhushi, A.;

Apparue dans: IEEE Transactions on Biomedical Engineering

Date publication: 05.-2012, volume: 59, issue:5, pages: 1205 - 1218

Editeur: IEEE

» A broadband and compact asymmetrical backward coupled-line coupler with high coupling level

Résumé:

Auteurs:

Apparue dans: AEU - International Journal of Electronics and Communications

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A Broadband U-Slot Coupled Microstrip-to-Waveguide Transition

Résumé:
A novel planar broadband microstrip-to-waveguide transition is proposed in this paper. The referred waveguide can be either rectangular waveguide or ridged waveguide. The transition consists of an open-circuited microstrip quarter-wavelength resonator and a resonant U-shaped slot on the upper broadside wall of a short-circuited waveguide. A physics-based equivalent-circuit model is also developed for interpreting the working mechanism and providing a coarse model for engineering design. The broadband transition can be regarded as a stacked two-pole resonator filter. Each coupling circuit can be approximately designed separately using the group-delay information at the center frequency. In addition to its broadband attribute, the transition is compact in size, vialess, and is highly compatible with planar circuits. These good features make the new transition very attractive for the system architecture where waveguide devices need to be surface mounted on a multilayered planer circuit. Two design examples are given to demonstrate the usefulness of the transition: one is a broadband ridged-waveguide bandpass filter and the other is a surface-mountable broadband low-temperature co-fired ceramic laminated waveguide cavity filter. Both filters are with the proposed transition for interfacing with microstrip lines, showing promising potentials in practical applications.

Auteurs: Huang, X.;Wu, K.-L.;

Apparue dans: IEEE Transactions on Microwave Theory and Techniques

Date publication: 05.-2012, volume: 60, issue:5, pages: 1210 - 1217

Editeur: IEEE

» A CFD greenhouse night-time condensation model

Résumé:

Auteurs:

Apparue dans: Biosystems Engineering

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A chaotic path planning generator for autonomous mobile robots

Résumé:

Auteurs:

Apparue dans: Robotics and Autonomous Systems

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A charge-pump and comparator based power-efficient pipelined ADC technique

Résumé:

Auteurs:

Apparue dans: Microelectronics Journal

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A clustering algorithm based on energy information and cluster heads expectation for wireless sensor networks

Résumé:

Auteurs: Graphical Abstract

Apparue dans: Computers & Electrical Engineering

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A CMOS Distributed Amplifier With Distributed Active Input Balun Using GBW and Linearity Enhancing Techniques

Résumé:
A CMOS distributed amplifier (DA) with distributed active input balun is presented that achieves a gain-bandwidth product of 818 GHz, while improving linearity. Each

cell within the DA employs dual-output two-stage topology that improves gain and linearity without adversely affecting bandwidth (BW) and power. Comprehensive analysis and simulations are carried out to investigate gain, BW, linearity, noise, and stability of the proposed

cell, and compare them with conventional

cells. Fabricated in a 65-nm low-power CMOS process, the 0.9-

DA achieves 22 dB of gain and a

of 10 dBm, while consuming dc power of 97 mW from a 1.3-V supply. A distributed balun, designed and fabricated in the same process, using the same

topology achieves a BW larger than 70 GHz and a gain of 4 dB with 19.5-mW power consumption from 1.3-V supply.

Auteurs: Jahanian, A.;Heydari, P.;

Apparue dans: IEEE Transactions on Microwave Theory and Techniques

Date publication: 05.-2012, volume: 60, issue:5, pages: 1331 - 1341

Editeur: IEEE

» A Coclustering Approach for Mining Large Protein-Protein Interaction Networks

Résumé:
Several approaches have been presented in the literature to cluster Protein-Protein Interaction (PPI) networks. They can be grouped in two main categories: those allowing a protein to participate in different clusters and those generating only nonoverlapping clusters. In both cases, a challenging task is to find a suitable compromise between the biological relevance of the results and a comprehensive coverage of the analyzed networks. Indeed, methods returning high accurate results are often able to cover only small parts of the input PPI network, especially when low-characterized networks are considered. We present a coclustering-based technique able to generate both overlapping and nonoverlapping clusters. The density of the clusters to search for can also be set by the user. We tested our method on the two networks of yeast and human, and compared it to other five well-known techniques on the same interaction data sets. The results showed that, for all the examples considered, our approach always reaches a good compromise between accuracy and network coverage. Furthermore, the behavior of our algorithm is not influenced by the structure of the input network, different from all the techniques considered in the comparison, which returned very good results on the yeast network, while on the human network their outcomes are rather poor.

Auteurs: Pizzuti, C.;Rombo, S.E.;

Apparue dans: IEEE/ACM Transactions on Computational Biology and Bioinformatics

Date publication: 05.-2012, volume: 9, issue:3, pages: 717 - 730

Editeur: IEEE

» A Colon Video Analysis Framework for Polyp Detection

Résumé:
This paper presents an automated video analysis framework for the detection of colonic polyps in optical colonoscopy. Our proposed framework departs from previous methods in that we include spatial frame-based analysis and temporal video analysis using time-course image sequences. We also provide a video quality assessment scheme including two measures of frame quality. We extract colon-specific anatomical features from different image regions using a windowing approach for intraframe spatial analysis. Anatomical features are described using an eigentissue model. We apply a conditional random field to model interframe dependences in tissue types and handle variations in imaging conditions and modalities. We validate our method by comparing our polyp detection results to colonoscopy reports from physicians. Our method displays promising preliminary results and shows strong invariance when applied to both white light and narrow-band video. Our proposed video analysis system can provide objective diagnostic support to physicians by locating polyps during colon cancer screening exams. Furthermore, our system can be used as a cost-effective video annotation solution for the large backlog of existing colonoscopy videos.

Auteurs: Park, S. Y.;Sargent, D.;Spofford, I.;Vosburgh, K. G.;A-Rahim, Y.;

Apparue dans: IEEE Transactions on Biomedical Engineering

Date publication: 05.-2012, volume: 59, issue:5, pages: 1408 - 1418

Editeur: IEEE

» A combined reactive and reinforcement learning controller for an autonomous tracked vehicle

Résumé:

Auteurs:

Apparue dans: Robotics and Autonomous Systems

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A Combined Series-Parallel Hybrid Envelope Amplifier for Envelope Tracking Mobile Terminal RF Power Amplifier Applications

Résumé:
An improved envelope amplifier architecture for envelope tracking RF power amplifiers is presented, consisting of two switching amplifiers and one linear amplifier. The first switching amplifier and the linear amplifier provide wideband and high-efficiency operation, while the second switching amplifier provides a reduced bandwidth variable supply to the linear amplifier to further reduce power loss. The first switching amplifier and the linear amplifier are fabricated together in a 150 nm CMOS process, while the second switching amplifier is external. Measurements show a maximum average efficiency of 82% for a 10 MHz LTE signal with a 6 dB PAPR at 29.7 dBm output power and an SFDR of 63 dBc for a single tone of 5 MHz driving an 8

load.

Auteurs: Hassan, M.;Larson, L. E.;Leung, V. W.;Asbeck, P. M.;

Apparue dans: IEEE Journal of Solid-State Circuits

Date publication: 05.-2012, volume: 47, issue:5, pages: 1185 - 1198

Editeur: IEEE

» A Communication Theoretical Modeling of Single-Layer Graphene Photodetectors and Efficient Multireceiver Diversity Combining

Résumé:
Graphene with groundbreaking properties has tremendous impact on physical sciences as 2-D atomic layer carbon sheet. Its unique electronic and photonic properties lead to applications such as transistors, graphene photodetectors (GPDs), and electronic circuit components. Metal–graphene–metal (MGM) GPDs with single- or multilayer graphene sheets are promising for future nanoscale optical communication architectures because of wide range absorption from far infrared to visible spectrum, fast carrier velocity, and advanced production techniques due to planar geometry. In this paper, signal-to-noise ratio (SNR), bit-error rate (BER), and data rate performances of nanoscale single-layer symmetric MGM photodetectors are analyzed for intensity modulation and direct detection (IM/DD) modulation. Shot and thermal noise limited (NL) performances are analyzed emphasizing graphene layer width dependence and domination of thermal NL characteristics for practical power levels. Tens of Gbit/s data rates are shown to be achievable with very low BERs for single-receiver (SR) GPDs. Furthermore, multireceiver (MR) GPDs and parallel line-scan (PLS) network topology are defined improving the efficiency of symmetric GPDs. SNR performance of SR PLS channels are both improved and homogenized with MR devices having the same total graphene area by optimizing their positions with max–min solutions and using maximal ratio and equal gain diversity combining techniques.

Auteurs: Gulbahar, B.;Akan, O. B.;

Apparue dans: IEEE Transactions on Nanotechnology

Date publication: 05.-2012, volume: 11, issue:3, pages: 601 - 610

Editeur: IEEE

» A Compact and Low Power 5–10 GHz Quadrature Local Oscillator for Cognitive Radio Applications

Résumé:
This paper presents the design and implementation of a compact and low power quadrature local oscillator (LO) for creating 13.3–20 GHz signal initially from a differentially tuned LC-VCO and then converting it to the desired 5–10 GHz with continuous frequency coverage. To accomplish such purpose, a 4-stage differential injection-locked ring oscillator (ILRO) is used subsequently to the latch-based divider to generate quadrature output phases without restricting 50% duty cycle from input signals as those of conventional divide-by-2 approaches. When implemented in a 65 nm general purpose CMOS IC technology, the integrated quadrature-phased LO consumes 22 mA of current at a 1 V supply and is able to exhibit the worst-case phase noise of

dBc/Hz at 1 MHz offset across the entire 5–10 GHz band for intended cognitive radio applications.

Auteurs: Lu, J.;Wang, N.-Y.;Chang, M.-C. F.;

Apparue dans: IEEE Journal of Solid-State Circuits

Date publication: 05.-2012, volume: 47, issue:5, pages: 1131 - 1140

Editeur: IEEE

» A compact dielectric elastomer tubular actuator for refreshable Braille displays

Résumé:

Auteurs:

Apparue dans: Sensors and Actuators A: Physical

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A compact low-profile dual-band antenna for WLAN and WAVE applications

Résumé:

Auteurs:

Apparue dans: AEU - International Journal of Electronics and Communications

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A Compact Wideband Microstrip Crossover

Résumé:
In this letter, a planar microstrip crossover junction is presented. The conductor-backed coplanar waveguide (CB-CPW) structure with vias is employed as the core part of the crossover design. The dimensions of the CB-CPW crossover itself are 11.3

11.3 mm

. Two kinds of the transitions between the microstrip line (MSL) and the CB-CPW structure are merged into a double side print circuit board. This presented crossover junction has a bandwidth from 10 up to 6000 MHz for 20 dB return loss, 1 dB insertion loss and

dB isolation. Compared with the other designs, this planar crossover features wide bandwidth and compact configuration.

Auteurs: Liu, W.;Zhang, Z.;Feng, Z.;Iskander, M. F.;

Apparue dans: IEEE Microwave and Wireless Components Letters

Date publication: 05.-2012, volume: 22, issue:5, pages: 254 - 256

Editeur: IEEE

» A comparative study of spacecraft attitude determination and estimation algorithms (A cost-benefit approach)

Résumé:

Auteurs: Graphical Abstract

Apparue dans: Aerospace Science and Technology

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A Comparative Study on Filtering Protein Secondary Structure Prediction

Résumé:
Filtering of Protein Secondary Structure Prediction (PSSP) aims to provide physicochemically realistic results, while it usually improves the predictive performance. We performed a comparative study on this challenging problem, utilizing both machine learning techniques and empirical rules and we found that combinations of the two lead to the highest improvement.

Auteurs: Kountouris, P.;Agathocleous, M.;Promponas, V.J.;Christodoulou, G.;Hadjicostas, S.;Vassiliades, V.;Christodoulou, C.;

Apparue dans: IEEE/ACM Transactions on Computational Biology and Bioinformatics

Date publication: 05.-2012, volume: 9, issue:3, pages: 731 - 739

Editeur: IEEE

» A comprehensive integration infrastructure for embedded system design

Résumé:

Auteurs:

Apparue dans: Microprocessors and Microsystems

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A computational study of high-frequency behavior of graphene field-effect transistors

Résumé:
High Frequency potential of graphene field-effect transistors (FETs) is explored by quasi-static self-consistent ballistic and dissipative quantum transport simulations. The unity power gain frequency fMAX and the cut-off frequency fT are modeled at the ballistic limit and in the presence of inelastic phonon scattering for a gate length down to 5 nm. Our major results are (1) with a thin high-κ gate insulator, the intrinsic ballistic fT is above 5 THz at a gate length of 10 nm. (2) Inelastic phonon scattering in graphene FETs lowers both fT and fMAX, mostly due to decrease of the transconductance. (3) fMAX and fT are severely degraded in presence of source and drain contact resistance. (4) To achieve optimum extrinsic fMAX performance, careful choice of DC bias point and gate width is needed.

Auteurs: Chauhan, Jyotsna;Liu, Leitao;Lu, Yang;Guo, Jing;

Apparue dans: Journal of Applied Physics

Date publication: 05.-2012, volume: 111, issue:9, pages: 094313 - 094313-7

Editeur: IEEE

» A computationally efficient numerical model of the offset of CMOS-integrated vertical Hall devices

Résumé:

Auteurs:

Apparue dans: Sensors and Actuators A: Physical

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A Continuous-Time Delta-Sigma Modulator for RF Subsampling Receivers

Résumé:
We propose a new continuous-time (CT) delta-sigma modulator (DSM) to be utilized in radio-frequency (RF) subsampling receivers for analog-to-digital conversion. Subsampling DSMs employ sub-Nyquist sampling with respect to the input signal frequency and oversampling with respect to the signal bandwidth. The proposed CT-DSM mitigates the effects of subsampling by modifying the feedback path of the modulator to accommodate the RF replica of the feedback signal and by enhancing the quality

factor of the loop filter. The novel modulator has significant improvements over previously published subsampling modulators as it provides jitter and image suppression and excess loop delay compensation to improve the dynamic range, thus enabling the modulator to be utilized in subsampling receivers when a relatively low sampling rate is desired.

Auteurs: Ucar, A.;Cetin, E.;Kale, I.;

Apparue dans: IEEE Transactions on Circuits and Systems II: Express Briefs

Date publication: 05.-2012, volume: 59, issue:5, pages: 272 - 276

Editeur: IEEE

» A continuum theory of thermoelectric bodies and effective properties of thermoelectric composites

Résumé:

Auteurs:

Apparue dans: International Journal of Engineering Science

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A control system for automated multiscale measuring systems

Résumé:

Auteurs:

Apparue dans: Mechatronics

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A Control Systems Concept Inventory Test Design and Assessment

Résumé:
Any meaningful initiative to improve the teaching and learning in introductory control systems courses needs a clear test of student conceptual understanding to determine the effectiveness of proposed methods and activities. The authors propose a control systems concept inventory. Development of the inventory was collaborative and iterative. The diagnostic test was administered to students before (pre) and after (post) student learning activities. Test responses were analyzed to provide instructors with feedback on their teaching. Using classical test theory and item response theory, aggregated results were analyzed to assess internal consistency and measurement error, respectively. Students demonstrated an improvement from pre- to post-test scores, showing gains of 23%–34% in understanding of new concepts learned. The internal consistency of the test has ranged from 0.61 to 0.68. It can be shown that the precision of the test is highest in the score range of 33%–66%, which is where most post-test scores occurred.

Auteurs: Bristow, M.;Erkorkmaz, K.;Huissoon, J. P.;Jeon, S.;Owen, W. S.;Waslander, S. L.;Stubley, G. D.;

Apparue dans: IEEE Transactions on Education

Date publication: 05.-2012, volume: 55, issue:2, pages: 203 - 212

Editeur: IEEE

» A Correlative Analysis Between Characteristics of FinFETs and SRAM Performance

Résumé:
A correlation between the characteristics of the 30-nm

fin-shaped field-effect transistors and the static random-access memory performance is precisely studied. By investigating an effect of the

variation to the static noise margin (SNM) variation of two different memory states of the storage node, it is revealed that the

variations of the pull-up, pull-down, and pass-gate transistors correlate with the SNM. Moreover, the contribution and the severity of each transistor variation to

are clarified.

Auteurs: Endo, K.;O'uchi, S.;Ishikawa, Y.;Liu, Y.;Matsukawa, T.;Sakamoto, K.;Tsukada, J.;Yamauchi, H.;Masahara, M.;

Apparue dans: IEEE Transactions on Electron Devices

Date publication: 05.-2012, volume: 59, issue:5, pages: 1345 - 1352

Editeur: IEEE

» A coupled mathematical model for simultaneous microwave and convective drying of wheat seeds

Résumé:

Auteurs:

Apparue dans: Biosystems Engineering

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A D-Band Passive Imager in 65 nm CMOS

Résumé:
Adifferential D-band (140 GHz) passive imager has been demonstrated in a 65 nm CMOS technology. It achieves a minimum noise equivalent power of

with peak responsivity of 1.2 MV/W. The core circuit consumes chip area of

with dc power consumption of 152 mW. This work further pushes imagers in CMOS technology working towards higher millimeter wave/sub millimeter wave frequencies.

Auteurs: Gu, Q. J.;Xu, Z.;Tang, A.;Frank Chang, M.-C.;

Apparue dans: IEEE Microwave and Wireless Components Letters

Date publication: 05.-2012, volume: 22, issue:5, pages: 263 - 265

Editeur: IEEE

» A decision support system for design of mass production machining lines composed of stations with rotary or mobile table

Résumé:

Auteurs:

Apparue dans: Robotics and Computer-Integrated Manufacturing

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A Decision Support System-Fertigation Simulator (DSS-FS) for design and optimization of sprinkler and drip irrigation systems

Résumé:

Auteurs:

Apparue dans: Computers and Electronics in Agriculture

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A DEM-based analysis of the influence of aggregate structure on suspension shear yield stress

Résumé:

Auteurs: Graphical Abstract

Apparue dans: Advanced Powder Technology

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A design methodology for integrated inductor-based DC-DC converters

Résumé:

Auteurs:

Apparue dans: Microelectronics Journal

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A dicing free SOI process for MEMS devices

Résumé:

Auteurs: Graphical Abstract

Apparue dans: Microelectronic Engineering

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A digitally configurable measurement platform using audio cards for high-resolution electronic transport studies

Résumé:
We report on a software-defined digitally configurable measurement platform for determining electronic transport properties in nanostructures with small readout signals. By using a high-resolution audio analog-to-digital/digital-to-analog converter in a digitally compensated bridge configuration we significantly increase the measurement speed compared to established techniques and simultaneously acquire large and small signal characteristics. We characterize the performance (16 bit resolution, 100 dB dynamic range at 192 kS/s) and demonstrate the application of this measurement platform for studying the transport properties of spin-valve nanopillars, a two-terminal device that exhibits giant magnetoresistance and whose resistance can be switched between two levels by applied magnetic fields and by currents applied by the audio card. The high resolution and fast sampling capability permits rapid acquisition of deep statistics on the switching of a spin-valve nanopillar and reduces the time to acquire the basic properties of the device – a state-diagram showing the magnetic configurations as function of applied current and magnetic field – by orders of magnitude.

Auteurs: Gopman, D. B.;Bedau, D.;Kent, A. D.;

Apparue dans: Review of Scientific Instruments

Date publication: 05.-2012, volume: 83, issue:5, pages: 054701 - 054701-4

Editeur: IEEE

» A Direct Approach Toward Global Minimization for Multiphase Labeling and Segmentation Problems

Résumé:
This paper intends to extend the minimization algorithm developed by Bae, Yuan and Tai [IJCV, 2011] in several directions. First, we propose a new primal-dual approach for global minimization of the continuous Potts model with applications to the piecewise constant Mumford–Shah model for multiphase image segmentation. Different from the existing methods, we work directly with the binary setting without using convex relaxation, which is thereby termed as a direct approach. Second, we provide the sufficient and necessary conditions to guarantee a global optimum. Moreover, we provide efficient algorithms based on a reduction in the intermediate unknowns from the augmented Lagrangian formulation. As a result, the underlying algorithms involve significantly fewer parameters and unknowns than the naive use of augmented Lagrangian-based methods; hence, they are fast and easy to implement. Furthermore, they can produce global optimums under mild conditions.

Auteurs: Gu, Y.;Wang, L.-L.;Tai, X.-C.;

Apparue dans: IEEE Transactions on Image Processing

Date publication: 05.-2012, volume: 21, issue:5, pages: 2399 - 2411

Editeur: IEEE

» A discrete-time framework for stability analysis of nonlinear networked control systems

Résumé:

Auteurs:

Apparue dans: Automatica

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A dynamic and quasi-centralized RWA method for optical fast circuit switching networks employing route pre-prioritization

Résumé:

Auteurs:

Apparue dans: Optical Switching and Networking

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A dynamic load balancing strategy with the push and pull approaches in DHT networks

Résumé:

Auteurs: Graphical Abstract

Apparue dans: Computers & Electrical Engineering

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A dynamic non-uniform segmentation method for first-order polynomial function evaluation

Résumé:

Auteurs:

Apparue dans: Microprocessors and Microsystems

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A dynamic saliency attention model based on local complexity

Résumé:

Auteurs:

Apparue dans: Digital Signal Processing

Date publication: 05.-2012

Editeur: Elsevier B.V.

Multiresolution Polygonal Approximation Algorithm for GPS Trajectory Simplification

» A Fast

Résumé:
Recent advances in geopositioning mobile phones have made it possible for users to collect a large number of GPS trajectories by recording their location information. However, these mobile phones with built-in GPS devices usually record far more data than needed, which brings about both heavy data storage and a computationally expensive burden in the rendering process for a Web browser. To address this practical problem, we present a fast polygonal approximation algorithm in 2-D space for the GPS trajectory simplification under the so-called integral square synchronous distance error criterion in a linear time complexity. The underlying algorithm is designed and implemented using a bottom–up multiresolution method, where the input of polygonal approximation in the coarser resolution is the polygonal curve achieved in the finer resolution. For each resolution (map scale), priority-queue structure is exploited in graph construction to construct the initialized approximated curve. Once the polygonal curve is initialized, two fine-tune algorithms are employed in order to achieve the desirable quality level. Experimental results validated that the proposed algorithm is fast and achieves a better approximation result than the existing competitive methods.

Auteurs: Chen, M.;Xu, M.;Franti, P.;

Apparue dans: IEEE Transactions on Image Processing

Date publication: 05.-2012, volume: 21, issue:5, pages: 2770 - 2785

Editeur: IEEE

Multiresolution Polygonal Approximation Algorithm for GPS Trajectory Simplification

» A Fast

Résumé:
Recent advances in geopositioning mobile phones have made it possible for users to collect a large number of GPS trajectories by recording their location information. However, these mobile phones with built-in GPS devices usually record far more data than needed, which brings about both heavy data storage and a computationally expensive burden in the rendering process for a Web browser. To address this practical problem, we present a fast polygonal approximation algorithm in 2-D space for the GPS trajectory simplification under the so-called integral square synchronous distance error criterion in a linear time complexity. The underlying algorithm is designed and implemented using a bottom-up multiresolution method, where the input of polygonal approximation in the coarser resolution is the polygonal curve achieved in the finer resolution. For each resolution (map scale), priority-queue structure is exploited in graph construction to construct the initialized approximated curve. Once the polygonal curve is initialized, two fine-tune algorithms are employed in order to achieve the desirable quality level. Experimental results validated that the proposed algorithm is fast and achieves a better approximation result than the existing competitive methods.

Auteurs: Minjie Chen;Mantao Xu;Franti, P.;

Apparue dans: IEEE Transactions on Image Processing

Date publication: 05.-2012, volume: 21, issue:5, pages: 2770 - 2785

Editeur: IEEE

» A Fast Algorithm for Errors-in-Variables Filtering

Résumé:
This note concerns the optimal estimation of the input and output sequences of linear time-invariant errors-in-variables (EIV) processes. An efficient recursive filtering algorithm is proposed. It is an innovation-based approach that relies on the triangular decomposition of block Toeplitz matrices introduced in . Unlike the other algorithms described in the literature, the proposed one is characterized by a computational complexity which increases only linearly with the order of the process. Both the SISO and MIMO cases are analyzed. An extension of the described algorithm to EIV models with colored input and output noises is considered as well.

Auteurs: Diversi, R.;

Apparue dans: IEEE Transactions on Automatic Control

Date publication: 05.-2012, volume: 57, issue:5, pages: 1303 - 1309

Editeur: IEEE

» A fast MPSoC virtual prototyping for intensive signal processing applications

Résumé:

Auteurs:

Apparue dans: Microprocessors and Microsystems

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A field study of two online dry-out methods for power transformers

Résumé:
Water slowly accumulates in transformers through various mechanisms, e.g., slow decomposition of paper insulation, contact between humid air and oil in a free-breathing conservator, and penetration through degraded sealing and absorption when the transformer is opened for maintenance [1].

Auteurs: Lelekakis, N.;Martin, D.;Guo, W.;Wijaya, J.;Lee, M.;

Apparue dans: IEEE Electrical Insulation Magazine

Date publication: 05.-2012, volume: 28, issue:3, pages: 32 - 39

Editeur: IEEE

» A Fixed-Frequency Beam-Steerable Half-Mode Substrate Integrated Waveguide Leaky-Wave Antenna

Résumé:
A single-layer design of a half-mode substrate integrated waveguide (HMSIW) leaky-wave antenna (LWA) possessing fixed-frequency beam steering capability is presented in this communication. The antenna is loaded by series and shunt capacitive tuning elements, providing two degrees of freedom in which its dispersion characteristic can be manipulated. An antenna with a length of 3.25

was implemented using fixed capacitors and experimentally validated. The measurements demonstrate a beam steering range between

and

at 6.5 GHz. The measured antenna gain is shown to be better than 9.5 dBi with circular polarization.

Auteurs: Suntives, A.;Hum, S. V.;

Apparue dans: IEEE Transactions on Antennas and Propagation

Date publication: 05.-2012, volume: 60, issue:5, pages: 2540 - 2544

Editeur: IEEE

» A Flexible ZnO Nanowire-Based Humidity Sensor

Résumé:
In this paper, the authors report the direct growth of ZnO nanowires (NWs) on a flexible substrate by the hydrothermal process and the fabrication of ZnO NW-based humidity sensor. It was found that average length and diameter of the ZnO NWs were 0.6 μm and 50 nm, respectively. It was also found that resistance of the ZnO NWs decreased by 45% as we increased the relative humidity from 52% to 90%. Furthermore, it was found that measured resistance was very stable with negligible fluctuation after 16 days continuous testing.

Auteurs: Hsueh, H. T.;Hsueh, T. J.;Chang, S. J.;Hung, F. Y.;Hsu, C. L.;Dai, B. T.;Lam, K. T.;Wen, K. H.;

Apparue dans: IEEE Transactions on Nanotechnology

Date publication: 05.-2012, volume: 11, issue:3, pages: 520 - 525

Editeur: IEEE

» A formal study of the nonlinearity and consistency of the Empirical Mode Decomposition

Résumé:

Auteurs:

Apparue dans: Signal Processing

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A Framework for Incorporating Functional Interrelationships into Protein Function Prediction Algorithms

Résumé:
The functional annotation of proteins is one of the most important tasks in the post-genomic era. Although many computational approaches have been developed in recent years to predict protein function, most of these traditional algorithms do not take interrelationships among functional terms into account, such as different GO terms usually coannotate with some common proteins. In this study, we propose a new functional similarity measure in the form of Jaccard coefficient to quantify these interrelationships and also develop a framework for incorporating GO term similarity into protein function prediction process. The experimental results of cross-validation on S. cerevisiae and Homo sapiens data sets demonstrate that our method is able to improve the performance of protein function prediction. In addition, we find that small size terms associated with a few of proteins obtain more benefit than the large size ones when considering functional interrelationships. We also compare our similarity measure with other two widely used measures, and results indicate that when incorporated into function prediction algorithms, our proposed measure is more effective. Experiment results also illustrate that our algorithms outperform two previous competing algorithms, which also take functional interrelationships into account, in prediction accuracy. Finally, we show that our method is robust to annotations in the database which are not complete at present. These results give new insights about the importance of functional interrelationships in protein function prediction.

Auteurs: Xiao-Fei Zhang;Dao-Qing Dai;

Apparue dans: IEEE/ACM Transactions on Computational Biology and Bioinformatics

Date publication: 05.-2012, volume: 9, issue:3, pages: 740 - 753

Editeur: IEEE

» A Framework for Managing Privacy-Enhancing Technology

Résumé:
The changing global business environment and continued introduction of new technologies are significantly affecting organizations' privacy practices. In this environment, privacy-enhancing technology (PET) often becomes a key to protecting personal information. A considerable amount of literature has discussed PET technologies and their benefits. However, the lack of clear organizational accountability can become a roadblock to effectively designing and implementing PET solutions. For organizations that don't employ these solutions, the result is increased regulatory and privacy risk and potential costs related to privacy breaches. Establishing a multidisciplinary privacy committee with clear roles and responsibilities assigned to various members is a possible approach to help address accountability.

Auteurs: Pelkola, David;

Apparue dans: IEEE Software

Date publication: 05.-2012, volume: 29, issue:3, pages: 45 - 49

Editeur: IEEE

» A Framework for the Evaluation of Inclinometer Data in the Measurement of Structures

Résumé:
This paper presents a new algebraic framework for modeling structures and computing the reconstruction of curves from local derivatives. This is the fundamental problem behind the use of inclinometers to measure the deformation of structures. A solid theoretical background, with derivations, is provided for the solution of a real and practical measurement problem. The reconstruction problem is solved using matrix algebraic techniques applied to variational calculus. Tikhonov, spectral, and a new regularization technique based on truncated constrained basis functions are implemented. It is proved that the solution of differential equations via basis functions corresponds to computing the spectra of the bending modes with respect to the basis functions used. This insight yields a method of determining the optimal set of basis functions based on spectral compactness. A completely new approach to computing a linear differential operator which yields a global estimator is presented. The method is also extended to yield a regularizing linear differential operator. The methods are verified, and the claims made substantiated by extensive numerical simulations including Monte Carlo simulations to verify the susceptibility of the solution to noise. The methods are also applied to a real measurement problem of determining the subsidence of rail track during construction in the vicinity of the track. Simultaneous reconstruction and temporal filtering is implemented.

Auteurs: O'Leary, P.;Harker, M.;

Apparue dans: IEEE Transactions on Instrumentation and Measurement

Date publication: 05.-2012, volume: 61, issue:5, pages: 1237 - 1251

Editeur: IEEE

» A Framework for the Observer Design for Networked Control Systems

Résumé:
This technical note proposes a framework for the observer design for networked control systems (NCS) affected by disturbances, via an emulation-like approach. The proposed model formulation allows us to consider various static and dynamic time-scheduling protocols, in-network processing implementations and encompasses sampled-data systems as a particular case. Provided that the continuous-time observer is robust to the measurement errors (in an appropriate sense) we derive bounds on the maximum allowable transmission interval that ensure the convergence of the observation errors under network-induced communication constraints. The stability analysis is trajectory-based and utilizes small-gain arguments. A number of observers can be combined and used within our approach to obtain estimators for NCS.

Auteurs: Postoyan, R.;Nesic, D.;

Apparue dans: IEEE Transactions on Automatic Control

Date publication: 05.-2012, volume: 57, issue:5, pages: 1309 - 1314

Editeur: IEEE

» A Frequency Domain Approach to Characterize and Analyze Load Profiles

Résumé:
This paper proposes a frequency domain approach to characterize and analyze load profiles. It first establishes the methodology and then discusses the prerequisite conditions and the benefits. Using real load data from three utilities, the paper will demonstrate that the customer classes' load profiles can be accurately represented by their significant harmonics in a compact and flexible format. The frequency domain statistics from the same load dataset is also analyzed and discussed to show the benefits and how new knowledge can be gained from using this approach.

Auteurs: Zhong, S.;Tam, K.-S.;

Apparue dans: IEEE Transactions on Power Systems

Date publication: 05.-2012, volume: 27, issue:2, pages: 857 - 865

Editeur: IEEE

» A Fully Differential CMOS–MEMS DETF Oxide Resonator With

and Positive TCF

Résumé:
A fully differential CMOS–MEMS double-ended tuning-fork (DETF) oxide resonator fabricated using a 0.18-

CMOS process has been demonstrated with a

greater than 4800 and more-than-20-dB stopband rejection at 10.4 MHz. The key to attaining such a performance attributes to the use of oxide structures with embedded metal electrodes, where

offers a

enhancement (at least a 3-times-higher

) as compared to other CMOS–MEMS-based composite resonators with similar structures and vibrating modes and where flexible electrical routing facilitates fully differential configuration to suppress capacitive feedthroughs. In addition, the resonators developed in this work possess a positive temperature coefficient of frequency

and mode-splitting capability, therefore indicating a great potential for temperature compensation and spurious-mode suppression, respectively. This technology paves a way to realize fully integrated CMOS–MEMS oscillators and filters which might benefit future single-chip transceivers for wireless communications.

Auteurs: Chen, W.-C.;Li, M.-H.;Liu, Y.-C.;Fang, W.;Li, S.-S.;

Apparue dans: IEEE Electron Device Letters

Date publication: 05.-2012, volume: 33, issue:5, pages: 721 - 723

Editeur: IEEE

» A Fully Differential CMOS–MEMS DETF Oxide Resonator With

and Positive TCF

Résumé:
A fully differential CMOS-MEMS double-ended tuning-fork (DETF) oxide resonator fabricated using a 0.18-μm CMOS process has been demonstrated with a Q greater than 4800 and more-than-20-dB stopband rejection at 10.4 MHz. The key to attaining such a performance attributes to the use of oxide structures with embedded metal electrodes, where SiO₂ offers a Q enhancement (at least a 3-times-higher Q) as compared to other CMOS-MEMS-based composite resonators with similar structures and vibrating modes and where flexible electrical routing facilitates fully differential configuration to suppress capacitive feedthroughs. In addition, the resonators developed in this work possess a positive temperature coefficient of frequency (TC_f) and mode-splitting capability, therefore indicating a great potential for temperature compensation and spurious-mode suppression, respectively. This technology paves a way to realize fully integrated CMOS-MEMS oscillators and filters which might benefit future single-chip transceivers for wireless communications.

Auteurs: Wen-Chien Chen;Ming-Huang Li;Yu-Chia Liu;Weileun Fang;Sheng-Shian Li;

Apparue dans: IEEE Electron Device Letters

Date publication: 05.-2012, volume: 33, issue:5, pages: 721 - 723

Editeur: IEEE

» A fully LMS/NLMS adaptive scheme applied to sparse-interpolated Volterra filters with removed boundary effect

Résumé:

Auteurs:

Apparue dans: Signal Processing

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A Fully Polarimetric Characterization of the Impact of Precipitation on Short Wavelength Synthetic Aperture Radar

Résumé:
When synthetic aperture radars (SAR) operating above 5 GHz began acquiring data clearly showing attenuation and backscatter from storms in the images, the notion that SAR is truly an “all weather” technology was challenged. With the recent launch of several dual-polarization X-band SAR systems, the capability of characterizing this impact became reality; however, a complete model describing SAR observations during precipitation is required to do this. Using real storm observations by fully polarimetric ground radars and microphysical models of electromagnetic scattering from hydrometeors, a quantitative characterization of the impact of precipitation on high-frequency SAR is presented here. The methodology is described to simulate X-band SAR observations of real storms from ground-based weather radars with an example of a squall line observed by the CSU-CHILL weather radar added to a TerraSAR-X image acquired at a different time. By conditioning the simulation on real data, the variability of radar observations is greatly reduced and more realistic than simulating from pure theoretical parameters. Given the challenges involved in characterizing the propagation effects, the results demonstrate the model capabilities well, and the results will apply to higher frequency systems for the future.

Auteurs: Fritz, J. P.;Chandrasekar, V.;

Apparue dans: IEEE Transactions on Geoscience and Remote Sensing

Date publication: 05.-2012, volume: 50, issue:5, pages: 2037 - 2048

Editeur: IEEE

-Band Butler Matrix End-Fire Beam-Switching Transmitter Using Flip-Chip Assembled CMOS Chips on LTCC

» A Fully SiP Integrated

Résumé:
In this paper, a fully system-in-package (SiP) integrated

-band Butler matrix beam-switching transmitter (TX) is presented. The CMOS chips from differential process technologies are assembled on a low-temperature co-fired ceramic (LTCC) substrate carrier by flip-chip interconnects. The vertically embedded folded monopole antenna is designed and integrated into the LTCC. The array consisting of four identical monopole antennas and a Butler matrix for beam switching is realized on the LTCC for loss reduction. Four switched main beams are measured and agree well with simulation. This beam-forming TX shows the potential of the low-cost millimeter-wave SiP with CMOS chips.

Auteurs: Kuo, C.-C.;Lu, H.-C.;Lin, P.-A.;Tai, C.-F.;Hsin, Y.-M.;Wang, H.;

Apparue dans: IEEE Transactions on Microwave Theory and Techniques

Date publication: 05.-2012, volume: 60, issue:5, pages: 1424 - 1436

Editeur: IEEE

-Band Butler Matrix End-Fire Beam-Switching Transmitter Using Flip-Chip Assembled CMOS Chips on LTCC

» A Fully SiP Integrated

Résumé:
In this paper, a fully system-in-package (SiP) integrated V-band Butler matrix beam-switching transmitter (TX) is presented. The CMOS chips from differential process technologies are assembled on a low-temperature co-fired ceramic (LTCC) substrate carrier by flip-chip interconnects. The vertically embedded folded monopole antenna is designed and integrated into the LTCC. The array consisting of four identical monopole antennas and a Butler matrix for beam switching is realized on the LTCC for loss reduction. Four switched main beams are measured and agree well with simulation. This beam-forming TX shows the potential of the low-cost millimeter-wave SiP with CMOS chips.

Auteurs: Che-Chung Kuo;Hsin-Chia Lu;Po-An Lin;Chen-Fang Tai;Yue-Ming Hsin;Huei Wang;

Apparue dans: IEEE Transactions on Microwave Theory and Techniques

Date publication: 05.-2012, volume: 60, issue:5, pages: 1424 - 1436

Editeur: IEEE

» A Fully-Integrated Efficient CMOS Inverse Class-D Power Amplifier for Digital Polar Transmitters

Résumé:
In this work, we have demonstrated a fully-integrated, high-efficiency CMOS inverse Class-D PA. Such efficient switching amplifiers can form the core of mixed-signal polar transmitters. A comprehensive analytical framework has been developed to determine optimum component values to maximize efficiency. Operating from a 1-V supply, the PA achieves a peak efficiency of 44% without any RF process options. This is comparable to that of state-of-the-art CMOS switching PAs despite using a much simpler output matching network.

Auteurs: Chowdhury, D.;Thyagarajan, S. V.;Ye, L.;Alon, E.;Niknejad, A. M.;

Apparue dans: IEEE Journal of Solid-State Circuits

Date publication: 05.-2012, volume: 47, issue:5, pages: 1113 - 1122

Editeur: IEEE

» A GaAs MEMS for AFM and spin injection

Résumé:

Auteurs:

Apparue dans: Sensors and Actuators A: Physical

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A gait rehabilitation strategy inspired by an iterative learning algorithm

Résumé:

Auteurs:

Apparue dans: Mechatronics

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A general algorithm for automated scheduling of drip irrigation in tree crops

Résumé:

Auteurs: Graphical Abstract

Apparue dans: Computers and Electronics in Agriculture

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A General Class of Outage Error Probability Lower Bounds in Bayesian Parameter Estimation

Résumé:
In this paper, a new class of lower bounds on the outage error probability in Bayesian parameter estimation is proposed. The outage error probability is an important criterion in parameter estimation that provides meaningful information even in the presence of large errors and is useful for prediction of the system operation region. Computation of the minimum outage error probability is usually not tractable and thus, lower bounds on this probability can be very useful for performance analysis. The proposed class of lower bounds on the outage error probability is derived using Hölder's inequality. Several bounds in the proposed class are presented. It is shown that the Ziv–Zakai lower bound on the outage error probability can be obtained from a subclass in the proposed class of bounds. The proposed class of bounds is utilized to derive a new class of Bayesian bounds on the mean-square error. It is shown that, for unimodal posterior probability density functions, the tightest lower bound on the probability of outage error in the proposed class attains the minimum probability of outage error. The proposed bounds are exemplified in linear Gaussian model parameter estimation and time-delay estimation.

Auteurs: Routtenberg, T.;Tabrikian, J.;

Apparue dans: IEEE Transactions on Signal Processing

Date publication: 05.-2012, volume: 60, issue:5, pages: 2152 - 2166

Editeur: IEEE

» A generalized synchrosqueezing transform for enhancing signal time-frequency representation

Résumé:

Auteurs:

Apparue dans: Signal Processing

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A Geometry-Based Doppler Centroid Estimator for Bistatic Forward-Looking SAR

Résumé:
For high-quality synthetic aperture radar (SAR) processing, Doppler centroid estimation is an essential procedure. An incorrect Doppler centroid would cause a loss of signal-to-noise ratio, an increase in the azimuth ambiguity level, and a shift in the location of the target. Based on the analysis of the range migration characteristic of the transmitter-fixed bistatic forward-looking SAR, a geometry-based Doppler centroid estimator is proposed in this letter. By searching for the range walk slope based on the minimum entropy, this method estimates the unambiguous Doppler centroid directly. Simulations validate the effectiveness of this method.

Auteurs: Wenchao Li;Jianyu Yang;Yulin Huang;Junjie Wu;

Apparue dans: IEEE Geoscience and Remote Sensing Letters

Date publication: 05.-2012, volume: 9, issue:3, pages: 388 - 392

Editeur: IEEE

» A Glucose-Specific Metric to Assess Predictors and Identify Models

Résumé:
In diabetes, the mean square error (MSE) metric is extensively used for assessing glucose prediction methods and identifying glucose models. One limitation of this metric is that, by equally treating errors in hypo-, eu-, and hyperglycemia, it is not able to weight the different clinical impact of errors in these three situations. In this paper, we propose a new cost function, which overcomes this limitation and can be used in place of MSE for several scopes, in particular for assessing the quality of glucose predictors and identifying glucose models. The new metric called glucose-specific MSE (gMSE) modifies MSE with a Clark error grid inspired penalty function, which penalizes overestimation in hypoglycemia and underestimation in hyperglycemia, i.e., the most harmful conditions on a clinical perspective. From a mathematical point of view, gMSE retains sensitivity of MSE and inherits some of its important mathematical features, in particular it has no local minima, simplifying the optimization. This makes it suitable for model identification purposes also. First, the goodness of it is demonstrated by means of three experiments, designed ad hoc to evidence its sensitivity to accuracy, precision, and distortion in glucose predictions. Second, a prediction assessment problem is presented, in which two real prediction profiles are compared. Results show that the MSE chooses the worst clinical situation, while gMSE correctly selects the situation with less clinical risk. Finally, we also demonstrate that models identified minimizing gMSE are more accurate in potentially harmful situations (hypo- and hyperglycemia) than those obtained by MSE.

Auteurs: Favero, S. D.;Facchinetti, A.;Cobelli, C.;

Apparue dans: IEEE Transactions on Biomedical Engineering

Date publication: 05.-2012, volume: 59, issue:5, pages: 1281 - 1290

Editeur: IEEE

» A greedy algorithm for feedrate planning of CNC machines along curved tool paths with confined jerk

Résumé:

Auteurs:

Apparue dans: Robotics and Computer-Integrated Manufacturing

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A Helmholtz-Stable Fast Solution of the Electric Field Integral Equation

Résumé:
A new fast matrix-vector multiplication scheme for the solution of the electric field integral equation is presented in this work. Similarly to other fast methods, our approach reduces the matrix-vector multiplication cost from

. Differently from other fast solvers, however, the effectiveness of EFIE preconditioning techniques such as quasi-Helmholtz decompositions or Calderón approaches is maintained by our method even for very high matrix compression rates. This is thanks to the fact that, in the scheme we are proposing, the contribution from the scalar potential when applied to or tested with solenoidal functions is always zero independent of the compression error. In addition, the new method will take advantage of the redundancies of the EFIE matrix in the low-frequency/dense discretization regime, and it will further decrease both the memory storage and the multiplication cost with respect to currently available fast solvers. Numerical results will show the effectiveness of our approach and its impact on the solution of realistic problems.

Auteurs: Andriulli, F. P.;Vecchi, G.;

Apparue dans: IEEE Transactions on Antennas and Propagation

Date publication: 05.-2012, volume: 60, issue:5, pages: 2357 - 2366

Editeur: IEEE

» A heterogeneous modular robotic design for fast response to a diversity of tasks

Résumé:

Auteurs:

Apparue dans: Robotics and Autonomous Systems

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A heuristic to adjust automatic capacitors using parameterization of load

Résumé:

Auteurs:

Apparue dans: International Journal of Electrical Power & Energy Systems

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A hierarchical language identification system for Indian languages

Résumé:

Auteurs:

Apparue dans: Digital Signal Processing

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A hierarchical Path Computation Element (PCE)-based k-random-paths routing algorithm in multi-domain WDM networks

Résumé:

Auteurs: Graphical Abstract

Apparue dans: Optical Switching and Networking

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A high-bandwidth, high-precision, two-axis steering mirror with moving iron actuator

Résumé:

Auteurs:

Apparue dans: Mechatronics

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A high-speed differential resistor ladder

Résumé:

Auteurs: Graphical Abstract

Apparue dans: Microelectronics Journal

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A hybrid method combining SOM-based clustering and object-based analysis for identifying land in good agricultural condition

Résumé:

Auteurs:

Apparue dans: Computers and Electronics in Agriculture

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A hybrid method for designing linear-phase quadrature mirror filter bank

Résumé:

Auteurs:

Apparue dans: Digital Signal Processing

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A hybrid SSD with PRAM and NAND Flash memory

Résumé:

Auteurs:

Apparue dans: Microprocessors and Microsystems

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A hybrid white organic light-emitting diode with stable color and reduced efficiency roll-off by using a bipolar charge carrier switch

Résumé:

Auteurs: Graphical Abstract

Apparue dans: Organic Electronics

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A K-band CMOS Differential Vackar VCO With the Gate Inductive Feedback

Résumé:
This brief presents a K-band differential Vackar voltage-controlled oscillator (VCO) with gate inductive feedback which enhances negative impedance and thus simplifies the startup condition. Simple analysis and simulations examine the transistor loading effect and amplitude stability. Results indicate that the Vackar VCO has improved amplitude stability compared to the Colpitts VCO. The improved amplitude stability is favorable for suppressing amplitude-to-phase noise conversion. The Vackar VCO was implemented in a 0.13-

RF CMOS process. The oscillation frequency ranged from 19 to 19.95 GHz. The measured phase noise at 1-MHz offset was

103 dBc/Hz at 19.5 GHz with a figure of merit of

182 dB.

Auteurs: Nguyen, T. N.;Lee, J.-W.;

Apparue dans: IEEE Transactions on Circuits and Systems II: Express Briefs

Date publication: 05.-2012, volume: 59, issue:5, pages: 257 - 261

Editeur: IEEE

» A knowledge-based prediction model of Verticillium wilt on potato and its use for rational crop rotation

Résumé:

Auteurs:

Apparue dans: Computers and Electronics in Agriculture

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A Koch-Like Sided Fractal Bow-Tie Dipole Antenna

Résumé:
A novel Koch-like fractal curve is proposed to transform ultra-wideband (UWB) bow-tie into so called Koch-like sided fractal bow-tie dipole. A small isosceles triangle is cut off from center of each side of the initial isosceles triangle, then the procedure iterates along the sides like Koch curve does, forming the Koch-like fractal bow-tie geometry. The fractal bow-tie of each iterative is investigated without feedline in free space for fractal trait unveiling first, followed by detailed expansion upon the four-iterated pragmatic fractal bow-tie dipole fed by 50-

coaxial SMA connector through coplanar stripline (CPS) and comparison with Sierpinski gasket. The fractal bow-tie dipole can operate in multiband with moderate gain (3.5–7 dBi) and high efficiency (60%-80%), which is corresponding to certain shape parameters, such as notch ratio

, notch angle

, and base angles

of the isosceles triangle. Compared with conventional bow-tie dipole and Sierpinski gasket with the same size, this fractal-like antenna has almost the same operating properties in low frequency and better radiation pattern in high frequency in multi-band operation, which makes it a better candidate for applications of PCS, WLAN, WiFi, WiMAX, and other communication systems.

Auteurs: Li, D.;Mao, J.;

Apparue dans: IEEE Transactions on Antennas and Propagation

Date publication: 05.-2012, volume: 60, issue:5, pages: 2242 - 2251

Editeur: IEEE

» A Leaky-Wave Analysis of the Phase Center in Fabry-Pérot Cavity Antennas

Résumé:
Phase centers are studied for Fabry-Pérot cavity antennas viewed as two-dimensional uniform leaky-wave antennas radiating pencil beams pointing at broadside. Alternative definitions for the phase center are considered and compared, as a function of the wavenumber of the relevant leaky waves and of the extension of the angular region of interest in the far field around the direction of maximum radiation amplitude. Analytical formulas are derived and numerical simulations of antennas constituted by planar grounded substrates covered with dielectric or metal partially-reflecting surfaces are provided to validate the analysis.

Auteurs: Burghignoli, P.;

Apparue dans: IEEE Transactions on Antennas and Propagation

Date publication: 05.-2012, volume: 60, issue:5, pages: 2226 - 2233

Editeur: IEEE

» A least-squares support vector machine (LS-SVM) based on fractal analysis and CIELab parameters for the detection of browning degree on mango (Mangifera indica L.)

Résumé:

Auteurs:

Apparue dans: Computers and Electronics in Agriculture

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A LIDAR-based crop height measurement system for Miscanthus giganteus

Résumé:

Auteurs:

Apparue dans: Computers and Electronics in Agriculture

Date publication: 05.-2012

Editeur: Elsevier B.V.

» A life of its own: The tenuous connection between Thales of Miletus and the study of electrostatic charging

Résumé:

Auteurs:

Apparue dans: Journal of Electrostatics

Date publication: 05.-2012

Editeur: Elsevier B.V.