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Fast Transforms for Acoustic Imaging-Part ii: applications

IEEE TRANSACTIONS ON IMAGE PROCESSING 2011年第8期20卷 2241-2247页

作者： Ribeiro, Flavio P. Nascimento, Vitor H. Univ Sao Paulo Dept Elect Syst Engn Escola Politecn BR-05508900 Sao Paulo Brazil

In Part I ["Fast Transforms for Acoustic Imaging-Part I: Theory," IEEE TRANSACTIONS ON IMAGE PROCESSING], we introduced the Kronecker array transform (KAT), a fast transform for imaging with separable arrays. Given a source distribution, the KAT produces the spectral matrix which would be measured by a separable sensor array. In Part ii, we establish connections between the KAT, beamforming and 2-D convolutions, and show how these results can be used to accelerate classical and state of the art array imaging algorithms. We also propose using the KAT to accelerate general purpose regularized least-squares solvers. Using this approach, we avoid ill-conditioned deconvolution steps and obtain more accurate reconstructions than previously possible, while maintaining low computational costs. We also show how the KAT performs when imaging near-field source distributions, and illustrate the trade-off between accuracy and computational complexity. Finally, we show that separable designs can deliver accuracy competitive with multi-arm logarithmic spiral geometries, while having the computational advantages of the KAT.

关键词： Acoustic imaging array imaging array processing fast transform regularized least-squares sparse reconstruction

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Recent trends in potentiometric sensor arrays-A review

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ANALYTICA CHIMICA ACTA 2010年第2期678卷 149-159页

作者： Bratov, A. Abramova, N. Ipatov, A. CSIC IMB CNM Barcelona 08193 Spain

Nowadays there exists a large variety of ion sensors based on polymeric or solid-state membranes that can be used in a sensor array format in many analytical applications. This review aims at providing a critical overview of the distinct approaches that were developed to build and use potentiometric sensor arrays based on different transduction principles, such as classical ion-selective electrodes (ISEs) with polymer or solid-state membranes, solid-contact electrodes (SCE) including coated wire electrodes (CWE), ion-sensitive field-effect transistors (ISFETs) and light addressable potentiometric sensors (LAPS) Analysing latest publications on potentiometric sensor arrays development and applications certain problems are outlined and trends are discussed (C) 2010 Elsevier B V All rights reserved

关键词： Potentiometric sensors sensor array Electronic tongue Multicomponent analysis

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ZnO nanowire arrays - Pattern generation, growth and applications

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PHYSICA STATUS solidI B-BASIC solid state PHYSICS 2010年第10期247卷 2305-2314页

作者： Zacharias, Margit Subannajui, Kittitat Menzel, Andreas Yang, Yang Univ Freiburg Inst Microsyst Engn IMTEK Fac Engn D-79110 Freiburg Germany

ZnO nanowires and related materials are in the focus of attention for electronic, optical or sensor applications. However, size, position and arrangement control are essential conditions for the development of future nanowire based devices. Various kinds of template methods including nanosphere lithography and UV laser interference lithography are powerful tools for the preparation of the starting metal catalyst arrays and will be demonstrated and discussed. However, only if the growth mechanism and its guiding parameters are understood in detail, the template will force a pattern arranged growth of nanowires. The paper gives an overview of the various kinds of growth modes for vertical arranged nanowires. Specific experimental conditions establishing the VS or the VLS growth are discussed. In addition, insight is given why the patterning is not all the time conserved and how to overcome these obstacles. In the second part different kinds of applications are summarized. Electronic properties are discussed based on metal semiconductor metal devices. The influence of a core shell nanowire structure on the optical properties is demonstrated. In addition, a simple approach for ZnO nanowire based gas sensors is discussed and shown. As a last example, the transfer of Al2O3 coated nanowires into spinel tubes is reported. [GRAPHICS] .

关键词： growth lithography nanowires photoluminescence templates

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Type-ii Superlattices - The Fraunhofer Perspective

Type-II Superlattices - The Fraunhofer Perspective

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Conference on Infrared Technology and applications XXXVI

作者： Rehm, Robert Walther, Martin Schmitz, Johannes Rutz, Frank Woerl, Andreas Scheibner, Ralf Ziegler, Johann Fraunhofer Inst Angew Festkorperphys IAF Tullastr 72 D-79108 Freiburg Germany AIM Infrarot Module GmbH D-74072 Heilbronn Germany

ISBN: (纸本)9780819481245

In the past years, the development of the type-ii InAs/GaSb superlattice technology at the Fraunhofer-Institute for Applied solid state Physics (IAF) has been focused on achieving series-production readiness for third generation dual-color superlattice detector arrays for the mid-wavelength infrared spectral range. The technology is ideally suited for airborne missile threat warning systems, due to its ability of low false alarm remote imaging of hot carbon dioxide signatures on a millisecond time scale. In a multi-wafer molecular beam epitaxy based process eleven 288x384 dual-color detector arrays are fabricated on 3 '' GaSb substrates. Very homogeneous detector arrays with an excellent noise equivalent temperature difference have been realized. The current article presents the type-ii superlattice dual-color technology developed at IAF and delivers insights into a range of test methodologies employed at various stages during the fabrication process, which ensure that the basic requirements for achieving high detector performance are met.

关键词： InAs/GaSb type-ii superlattice photodiode missile threat warning carbon dioxide third generation infrared imager dual-color infrared camera dual-band IR camera GaSb substrate carrier background

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2010 IEEE Asian solid-state Circuits Conference, A-SSCC 2010

2010 IEEE Asian Solid-State Circuits Conference, A-SSCC 2010

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2010 6th IEEE Asian solid-state Circuits Conference, A-SSCC 2010

ISBN: (纸本)9781424482979

The proceedings contain 97 papers. The topics discussed include: future television - super hi-vision and beyond;asymmetric cross-coupled sense amplifier for small-sized 0.5-V gigabit-DRAM arrays;a 28 nm dual-port SRAM macro with screening circuitry against write-read disturb failure;a multi-mode digital controller with windowed ADC and self-calibrated DPWM for slew-enhanced switching converter;a 1-V input, 0.2-V to 0.47-V output switched-capacitor DC-DC converter with pulse density and width modulation (PDWM) for 57% ripple reduction;an ultra-low-cost RFID tag with 1.67 Gbps data rate by ink-jet printing on paper substrate;low noise capacitive sensor for multi-touch mobile handset's applications;a 31mA CMOS wideband BD-ii B2&B3 mode receiver with 55dB gain dynamic range;a high-speed, on-chip implementation of Teager Kaiser operator for in-band interference rejection;a 40-GHz phase-locked loop for 60-GHz sliding-IF transceivers in 65nm CMOS;and a 0.45V-to-2.7V inductive-coupling level shifter.

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Bottom-up fabrication approaches to large area novel plasmonic materials

Bottom-up fabrication approaches to large area novel plasmon...

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中国光学学会2010年光学大会

作者：王振林 Department of Physics and National Laboratory of Solid State Microstructures Nanjing University

Recent research effort towards fabricating novel metal nanoparticles （NPs） and their ordered arrays have been motivated by the emergence of *** particular,tuning the size,morphology,composition,and the separation of metal NPs has allowed us to engineer both individual nanoparticles and collective properties of plasmonic crystals for specific *** we present our recent development of bottom-up growth methods and demonstrate convenience for the preparation of such plasmonic *** implementation of physical,chemical,or electrochemical deposition of a metal in combination with micromolding on two-dimensional colloidal crystals,ordered metallic NPs with a variety of morphologies can be created with a nanometer spatial tuning *** prepared novel plasmonic crystals could find applications in optics,optoelectronics,materials science,sensing and biophysics.

关键词： Surface plasmons plasmonic crystal colloidal crystal light transmission resonance plasmonic sensor

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Investigation, design, and commercialization of actively-enhanced solid-state gas sensor arrays

Investigation, design, and commercialization of actively-enh...

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作者： Blackburn, Bryan Michael University of Florida

学位级别：Ph.D.

Low cost, high-performance gas sensors are needed for many applications in order to quantify (parts per billion, ppb, to parts per million, ppm) concentrations of individual species in complex gas mixtures. These devices must often function reliably over long periods of time (e.g., months to years) without any possibility for recalibration (i.e., they must be stable). Such gas sensors are significant for many applications and industries, including possible improvements in energy efficiency, pollutant emissions, process control, disease diagnostics, and more. This work involved the development of methods to “actively” enhance the performance of potentiometric gas sensors. Such devices, based on coupling two electrodes (either metals and/or semiconducting oxides) to a solid electrolyte, have been studied in one form or another for over 100 years; though only recently have breakthroughs provided insight into the development of solid-state gas sensors capable of selectively quantifying low levels of individual species of interest in complex gas mixtures. In this work, local modifications in temperature and the electric field about the sensing electrodes were explored to enhance device performance. This involved the fabrication and testing of many devices, including prototype multifunctional gas sensor arrays for selectively detecting multiple gas species (e.g., NO and NO 2) in the presence of others. Electrical properties of the devices provided insight into the mechanisms behind the “active” enhancements. Several surface science techniques were used to further investigate the sensing mechanisms of the devices and the “active” enhancement methods for the sensors and potentially other solid-state ionic devices. During the course of the work, materials were developed for use with a cutting-edge direct-write tool for rapid prototyping of solid-state ionic devices, including gas sensors and solid oxide fuel cells. Finally, R&D procedures were improved through automated expe

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Potential and Limitations of a Deconvolution Approach for Guided Wave Structural Health Monitoring

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STRUCTURAL HEALTH MONITORING-AN INTERNATIONAL JOURNAL 2009年第5期8卷 381-395页

作者： Cicero, T. Cawley, P. Simonetti, F. Rokhlin, S. I. Univ London Imperial Coll Sci Technol & Med UK Res Ctr NDE London SW7 2AZ England Ohio State Univ Columbus OH 43210 USA

Ultrasonic guided waves offer the possibility of inspecting large areas of structures from a small number of sensor positions. However, inspection of complex structures is difficult as the reflections from different features overlap. Estimating the number and amplitude of the wave packets in ultrasonic time traces is crucial for the development of a guided wave inspection system, in order to detect and locate damage. Deconvolution has been extensively used in geophysical applications to resolve overlapping echoes in the recorded signals. The main objective of this work was to evaluate the applicability of the deconvolution approach for enhancing the resolution of ultrasonic time traces in structural health monitoring (SHM). Numerical simulations on strongly overlapping signals were carried out to evaluate the performance of the two techniques that have been considered: (i) Wiener filter, (ii) single most likely replacement. It was shown that the relatively narrow bandwidth of the input signals and phase shifts between different reflections limit the benefits obtained from deconvolution and it was concluded that deconvolution is unlikely to be useful for guided wave SHM applications.

关键词： structural health monitoring sparse sensor arrays signal processing signal deconvolution

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基于嵌入式应用的指纹识别系统设计与实现

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山西科技 2010年第4期25卷 32-33,37页

作者：任丽君陈蕾苏州大学电子信息学院江苏苏州215006

随着指纹识别技术的发展和嵌入式系统的广泛应用,指纹识别逐渐向嵌入式方向发展。利用Fujitsu公司的电容式固态指纹传感器MBF200、Samsung公司的ARMS3C2410处理器和uC/OSⅡ操作系统,扩展了相应外部设备,构建了一个通用型基于嵌入式应用... 详细信息

随着指纹识别技术的发展和嵌入式系统的广泛应用,指纹识别逐渐向嵌入式方向发展。利用Fujitsu公司的电容式固态指纹传感器MBF200、Samsung公司的ARMS3C2410处理器和uC/OSⅡ操作系统,扩展了相应外部设备,构建了一个通用型基于嵌入式应用的指纹检测与处理模块的指纹识别系统。通过实验验证,该系统能够完成指纹图像的获取与匹配工作。

关键词：指纹识别指纹特征嵌入式应用

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Vertically Aligned Carbon Nanofibers: Interconnecting solid state Electronics with Biosystems

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JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2009年第8期9卷 5038-5046页

作者： Cassell, Alan M. Li, Jun Nguyen-Vu, Thuy-Duong Barbara Koehne, Jessica E. Chen, Hua Andrews, Russell Meyyappan, M. Univ Calif Santa Cruz UARC NASA Ames Res Ctr Moffett Field CA 94035 USA Kansas State Univ Dept Chem Manhattan KS 66506 USA

Vertically aligned carbon nanofibers (VACNFs) are grown directly on prefabricated electronic circuits with nanoscale precision. Utilizing the free-standing nanofiber array geometry, we have demonstrated the detection of nucleic acids to construct an ultrasensitive electrochemical sensor. Extending this technology towards in vivo applications, we have modified the free-standing VACNF arrays in order to achieve a multifunctional three dimensional (3-D) matrix that interpenetrates the neuronal network of PC12 cells. We found that PC12 cells cultured on the nanofiber arrays can form an extended neural network upon proper chemical and biochemical modification. The soft 3-D nanofiber array architecture provides a novel platform to fine-tune the topographical, mechanical, chemical, and electrical cues at sub-cellular scales. This biomaterial platform can be used for both fundamental studies of nanomaterial-cell interactions and the development of multifunctional, chronically stable implantable devices. The application of these devices and potential utility as a multifunctional platform for neurophysiology and biochemical studies will be discussed.

关键词： Neural Interface Carbon Nanofiber Vertically Aligned Polypyrrole Nucleic Acid Detection Electrochemical Methods Neurotransmitter Dopamine Implantable Electrode PC12 Cells Biocompatibility

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