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IEEE Wireless Communications and Networking Conference 2010, WCNC 2010

作者： Al-Qahtani, Fawaz S. Duong, Trung Q. Gurung, Arun K. Bao, Vo Nguyen Quoc National Satellite Technology Program Saudi Arabia Radio Communication Group Blekinge Institute of Technology Sweden School of Electrical and Computer Engineering RMIT University Melbourne VIC Australia Department of Electrical Engineering University of Ulsan Korea Republic of

ISBN: (纸本)9781424463985

In this paper, we investigate the average symbol error probability (SEP) of fixed decode-and-forward relay networks over independent but not identically distributed Nakagami-m fading channels. We have derived closed form expression of SEP for general rectangular quadrature amplitude modulation (QAM) under relay selection scheme where only the best relay forwards message from the source to the destination. The expressions are in terms of hypergeometric series which can be efficiently numerically evaluated. The numerical results are validated with Monte-Carlo simulations. ©2010 IEEE.

关键词： Quadrature amplitude modulation

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HermesD: A high-rate long-range wireless transmission system for simultaneous multichannel neural recording applications

HermesD: A high-rate long-range wireless transmission system...

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作者： Miranda, Henrique Gilja, Vikash Chestek, Cindy A. Shenoy, Krishna V. Meng, Teresa H. Department of Electrical Engineering Stanford University Stanford CA 94305 United States Department of Computer Science Stanford University Stanford CA 94305 United States Departments of Electrical Engineering and Bioengineering Neurosciences Program Stanford University Stanford CA 94305 United States

HermesD is a high-rate, low-power wireless transmission system to aid research in neural prosthetic systems for motor disabilities and basic motor neuroscience. It is the third generation of our Hermes systems aimed at recording and transmitting neural activity from brain-implanted electrode arrays. This system supports the simultaneous transmission of 32 channels of broadband data sampled at 30 ks/s, 12 b/sample, using frequency-shift keying modulation on a carrier frequency adjustable from 3.7 to 4.1 GHz, with a link range extending over 20 m. The channel rate is 24 Mb/s and the bit stream includes synchronization and error detection mechanisms. The power consumption, approximately 142 mW, is low enough to allow the system to operate continuously for 33 h, using two 3.6-V/1200-mAh Li-SOCl2batteries. The transmitter was designed using off-the-shelf components and is assembled in a stack of three 28 mm × 28-mm boards that fit in a 38 mm × 38 mm × 51-mm aluminum enclosure, a significant size reduction over the initial version of HermesD. A 7-dBi circularly polarized patch antenna is used as the transmitter antenna, while on the receiver side, a 13-dBi circular horn antenna is employed. The advantages of using circularly polarized waves are analyzed and confirmed by indoor measurements. The receiver is a stand-alone device composed of several submodules and is interfaced to a computer for data acquisition and processing. It is based on the superheterodyne architecture and includes automatic frequency control that keeps it optimally tuned to the transmitter frequency. The HermesD communications performance is shown through bit-error rate measurements and eye-diagram plots. The sensitivity of the receiver is - 83 dBm for a bit-error probability of 10-9. Experimental recordings from a rhesus monkey conducting multiple tasks show a signal quality comparable to commercial acquisition systems, both in the low-frequency (local field potentials) and upper-frequency bands (act

关键词： Transmitters

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Why Gabor frames? Two fundamental measures of coherence and their role in model selection

Why Gabor frames? Two fundamental measures of coherence and ...

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作者： Bajwa, Waheed U. Calderbank, Robert Jafarpour, Sina Department of Electrical Engineering Program in Applied and Computational Mathematics Princeton University Princeton NJ 08544 United States Department of Computer Science Princeton University Princeton NJ 08544 United States

The problem of model selection arises in a number of contexts, such as subset selection in linear regression, estimation of structures in graphical models, and signal denoising. This paper studies non-asymptotic model selection for the general case of arbitrary (random or deterministic) design matrices and arbitrary nonzero entries of the signal. In this regard, it generalizes the notion of incoherence in the existing literature on model selection and introduces two fundamental measures of coherence- termed as the worst-case coherence and the average coherence-among the columns of a design matrix. It utilizes these two measures of coherence to provide an in-depth analysis of a simple, model-order agnostic one-step thresholding (OST) algorithm for model selection and proves that OST is feasible for exact as well as partial model selection as long as the design matrix obeys an easily verifiable property, which is termed as the coherence property. One of the key insights offered by the ensuing analysis in this regard is that OST can successfully carry out model selection even when methods based on convex optimization such as the lasso fail due to the rank deficiency of the submatrices of the design matrix. In addition, the paper establishes that if the design matrix has reasonably small worst-case and average coherence then OST performs near-optimally when either (i) the energy of any nonzero entry of the signal is close to the average signal energy per nonzero entry or (ii) the signal-to-noise ratio in the measurement system is not too high. Finally, two other key contributions of the paper are that (i) it provides bounds on the average coherence of Gaussian matrices and Gabor frames, and (ii) it extends the results on model selection using OST to low-complexity, model-order agnostic recovery of sparse signals with arbitrary nonzero entries. In particular, this part of the analysis in the paper implies that an Alltop Gabor frame together with OST can successfully carr

关键词： Recovery

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PDMS stretchable platforms for the studies of mechanical compression on neurogenesis

PDMS stretchable platforms for the studies of mechanical com...

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4th IEEE International Conference on Nano/Molecular Medicine and engineering, IEEE NANOMED 2010

作者： Esfandiari, Leyla Tang, William C. Biomedical Engineering Interdepartmental Program University of California Los Angeles CA United States Department of Biomedical Engineering University of California Irvine CA United States Department of Electrical Engineering and Computer Science University of California Irvine CA United States

ISBN: (纸本)9781612841533

The use of MEMS to study the effect of mechanical compression on neurogenesis has been demonstrated. Polydimethylsiloxane- (PDMS)-based stretchable platforms were used on neurosphere assay to investigate the role of mechanical forces on the formation of radial glial processes, neuronal generation and migration. To induce mechanical compression on neurospheres, The PDMS culturing substrate is patterned with micron-sized wells. Neurospheres are cultured on the prestretched device. After 48 hours, when neurospheres are grown to the size of the well's width, the stretched substrate is released. The experimental results showed that applied mechanical compression on neural stem cells cultured as neurospheres could be a factor accelerating the radial glial formation, which is associated to neurogenesis and neuronal migration. © 2010 IEEE.

关键词： Polydimethylsiloxane

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Development of engineering-related minors for non-engineering students

Development of engineering-related minors for non-engineerin...

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2010 ASEE Annual Conference and Exposition

作者： Krupczak, John Mina, Mani Gustafson, Robert J. Young, James Department of Engineering Hope College United States Program High Speed Systems Engineering Laboratory Iowa State University United States Department of Engineering Education Engineering Education Innovation Center Ohio State University United States Department of Electrical and Computer Engineering Rice University United States

Many Americans lack even a rudimentary understanding of the principles underlying the technology essential for daily life. engineering concepts are pervasive in decision making within industry, government, education, and health care, yet most decisions in these sectors are made by people with little or no formal engineering education. This research will develop minors to be offered by engineering units as an approach to developing technological competence in non-engineers. A collaboration between Iowa State University, Ohio State University, Hope College, and Rice University is building on the promising results achieved in the Minor in engineering Studies program at Iowa State. The project goal is to develop the concepts and resources to support model minors which can be adopted efficiently and widely within American higher education. To facilitate adoption by other institutions, flexibility is a key objective of the intended guidelines. Since the appropriateness of using the name engineering in the context of a minor is subject to debate, the specific name of minor should be part of that flexibility. These degrees do not focus on teaching specific engineering technical content but on teaching students how to think like an engineer. The minor aims to develop the broad understanding and practical technological competence outlined by the National Academy of engineering in reports such as Technically Speaking. Thus decoupled from the engineering major, the Minor in engineering Studies at Iowa has attracted students majoring in business, communications, journalism, and design. Minors provide a recognized credential deemed attractive by many students. This work will develop a set of Technological Literacy Objectives and Outcomes for such a minor. These outcomes will be similar to the ABET a-k outcomes that are used for engineering degrees, but will be focused on developing technologically literate citizens. The anticipated use of a standard set of outcomes rather than a

关键词： Students

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Haptic playback: Better trajectory tracking during training does not mean more effective motor skill transfer

Haptic playback: Better trajectory tracking during training ...

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International Conference on Haptics: Generating and Perceiving Tangible Sensations, EuroHaptics 2010

作者： Kolesnikov, Maxim Žefran, Miloš Sensory Motor Performance Program Rehabilitation Institute of Chicago Chicago IL United States Department of Electrical and Computer Engineering University of Illinois at Chicago Chicago IL United States

ISBN: (纸本)3642140742

In this paper the performance of a haptic playback system with two different control algorithms was experimentally investigated. Accuracy of tracking the reference position and force trajectories of each system during training was examined, and their effectiveness in teaching a hybrid sensorimotor skill with significant position and force components was compared. It was determined that superior tracking performance during training does not necessarily indicate superior effectiveness in motor skill acquisition. © 2010 Springer-Verlag Berlin Heidelberg.

关键词： computers

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An automated bottle filling and capping project for freshman engineering students

An automated bottle filling and capping project for freshman...

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2010 ASEE Annual Conference and Exposition

作者： Meah, Kala Garrison, Timothy Kearns, James Link, Gregory Garrison, Laura Blanding, Wayne Celik, Emine Kuchnicki, Stephen Dawson, Jennifer McFarland, Barry Department of Physical Science York College of Pennsylvania United States Mechanical Engineering Program York College of Pennsylvania United States Department of Electrical and Computer Engineering York College of Pennsylvania United States Department of Thermal Sciences Freshmen Design Courses and Computer Programming York College of Pennsylvania United States Department of Electrical Engineering York College of Pennsylvania United States York College of Pennsylvania United States Department of Mechanical Engineering York College of Pennsylvania United States

All freshman engineering students at York College participate in a spring semester design challenge as part of a year-long, two-course introduction to engineering. This paper describes the course organization, the project goals, and project itself and how it supports the broader engineering curriculum goals of engaging freshman engineering students in a design project, exposing them in an interesting way to the breath of engineering, and motivating them in their engineering studies. The students work in small teams and have roughly 12 weeks to design an automated electromechanical system that first transports three empty Snapple bottles, three tennis balls, and 36 oz. of water to a 2/x3/ operational zone. The machine must fill each bottle with 12 oz. of water, cap each bottle by covering the top with a tennis ball, and then deliver the capped and filled bottles to an area outside of the operational zone. The bottle-filling project serves as the second of two interdisciplinary engineering design experiences during the freshman year. It introduces aspects of computer, electrical, and mechanical engineering, including the following five primary knowledge areas: (i) machining and fabrication;(ii) electronic circuit prototyping and programming;(iii) sensor and actuator applications;(iv) mechanical design;(v) project planning;and (vi) presentation skills. A project demonstration at the end of the semester determines the relative effectiveness of each machine based upon a number of quantitative factors, including the total time required to complete the overall process, the volume of water in each bottle, the number of bottles successfully capped, the amount of water spilled, and approximate manufacturing cost. Some qualitative factors considered are simplicity, creativity, and aesthetics. Student interest in this substantial hands-on experience, as measured by surveys and exhibited by attendance, enthusiasm, productivity, and success, appears to be high through the three y

关键词： Bottles

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SHOT: Single-beam Holographic Tomography

SHOT: Single-beam Holographic Tomography

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2010亚洲光电子会议信息光学和光存储技术分会场

作者： Georges Nehmetallah Partha P. Banerjee Department of Electrical and Computer Engineering and Electro-Optics Program University of Dayton

A novel single-beam holographic tomography (SHOT) based technique is used for the recording and reconstruction of 3D shapes of water droplets, leading to quantification of the radii of curvatures along the surface, dr... 详细信息

关键词： digital holography, tomography, Radon transform

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Experimental measurement of growth patterns on fossil corals:Secular variation in ancient Earth-Sun distances

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Chinese Science Bulletin 2010年第35期55卷 4010-4017页

作者： ZHANG WeiJia1,3,4,LI ZhengBin2,3 & LEI Yang1 1 department of Physics,Peking University,Beijing 100871,China 2 department of electrical engineering and computer Science,Peking University,Beijing 100871,China 3 State Key Laboratory of Advanced Optical Communication Systems & Networks,Peking University,Beijing 100871,China 4 Committee of Yuanpei Honors program,Peking University,Beijing 100871,China Department of Physics Peking University Beijing 100871 China State Key Laboratory of Advanced Optical Communication Systems & Networks Peking University Beijing 100871 China Committee of Yuanpei Honors Program Peking University Beijing 100871 China Department of Electrical Engineering and Computer Science Peking University Beijing 100871 China

In recent years,much attention has been given to the increase in the Earth-Sun distance,with the modern rate reported as 5-15 m/cy on the basis of astronomical ***,traditional methods cannot measure the ancient leaving rates,so a myriad of research attempting to provide explanations were met with unmatched *** this paper we consider that the growth patterns on fossils could reflect the ancient Earth-Sun *** mechanical analysis of both the Earth-Sun and Earth-Moon systems,these patterns confirmed an increase in the Earth-Sun *** a large number of well-preserved specimens and new technology available,both the modern and ancient leaving rates could be measured with high precision,and it was found that the Earth has been leaving the Sun over the past 0.53 billion *** Earth's semi-major axis was 146 million kilometers at the beginning of the Phanerozoic Eon,equating to 97.6% of its current *** modern leaving rates are 5-14 m/cy,whereas the ancient rates were much *** results indicate a special expansion with an average expansion coefficient of 0.57H0 and deceleration in the form of Hubble *** the basis of experimental results,the Earth's semi-major axis could be represented by a simple formula that matches fossil measurements.

关键词：地球太阳古代距离生长模式实验石珊瑚量化

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The effect of gender on support and self-efficacy in undergraduate engineering programs

The effect of gender on support and self-efficacy in undergr...

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2010 ASEE Annual Conference and Exposition

作者： Reisberg, Rachelle Bailey, Margaret Burger, Carol Hamann, Jerry Raelin, Joe Whitman, David Women in Engineering Program Northeastern University United States WE RIT Kate Gleason College of Engineering Rochester Institute of Technology United States Department of Computer Science University of Wyoming United States Program for Women and Girls HRD Division NSF United States College of Business Administration Department of Practice-Oriented Education Northeastern University United States Electrical and Computer Engineering Department University of Wyoming United States

This study is part of a larger research project, supported by a National Science Foundation Research on Gender in Science and engineering program grant, designed to determine the effect of self-efficacy and other factors on the retention of women in undergraduate engineering programs. These data represent the first wave of the study completed in the 2008-2009 academic year of sophomores in the colleges of engineering from four participating universities: Northeastern University, Rochester Institute of Technology, Virginia Polytechnic Institute, and the University of Wyoming. The study examines the effect of gender on a range of contextual supports to explain three dimensions of self-efficacy: work, career, and academic within undergraduate engineering. Contextual support is defined as the institutional support provided to students through a number of mechanisms, such as financial aid, mentorship, and participation in living/learning communities. The analyses revealed some significant differences by gender. With the exception of academic self-efficacy, which is significantly higher among males, every other significant difference favors the female population. As freshmen, women are not as confident as men in their likelihood of achieving success in their engineering major. However, they were found to have higher career self-efficacy, in contrast to what has been reported in the literature, and benefit far more from mentorship. They also exceed the scores of their male counterparts in five support dimensions: they report receiving more support from professional clubs and associations;they are more involved in campus life;they take more advantage of living/learning communities;and they report that they not only receive more support from their friends but that their friends really matter to them. © American Society for engineering Education, 2010.

关键词： Professional aspects

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