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131.
介绍一种在实验室条件下对电视系统环境光照度适应范围测试的光圈性能测试仪.包括系统的组成和工作原理、主要技术难点及解决办法,给出了已达到的技术指标.该装置光学耦合系统的分辨率高,图像照度调整范围大、精度好、仪器结构紧凑,重量轻,性能稳定可靠. 相似文献
132.
UV Sensors: Materials and Device Designs for an Epidermal UV Colorimetric Dosimeter with Near Field Communication Capabilities (Adv. Funct. Mater. 2/2017) 下载免费PDF全文
133.
A semiconductor luminescence formula is derived that includes phonon replica of arbitrary order based on a non-perturbative treatment of the electron–phonon interaction. The formula is used to analyze the extraordinarily strong sidebands observed with ZnO nanorods in recent experiments. Sidebands due to free and impurity-bound excitons are compared, and the generic differences between bulk and quantum-well emission are discussed. 相似文献
134.
135.
文中对近年来有关高温铜氧化物超导体(HTS)的某些重要实验的进展情况作了评述。强调目前处于HTS实验研究应起主导作用的阶段,特别是对HTS电子液体中反常电荷分布的观察,察微观瞬的技术改进实验结果,有助于解决对HTS超导机制的争论。对HTS的应用基础技术提出了建议方向。 相似文献
136.
In this paper, we present error-resilient Internet video transmission using path diversity and rate-distortion optimized reference
picture selection. Under this scheme, the optimal packet dependency is determined adapting to network characteristics and
video content, to achieve a better trade-off between coding efficiency and forming independent streams to increase error-resilience.
The optimization is achieved within a rate-distortion framework, so that the expected end-to-end distortion is minimized under
the given rate constraint. The expected distortion is calculated based on an accurate binary tree modeling with the effects
of channel loss and error concealment taken into account. With the aid of active probing, packets are sent across multiple
available paths according to a transmission policy which takes advantage of path diversity and seeks to minimize the loss
rate. Experiments demonstrate that the proposed scheme provides significant diversity gain, as well as gains over video redundancy
coding and the NACK mode of conventional reference picture selection.
Yi Liang received the Ph.D. degree in Electrical Engineering from Stanford University in 2003. His expertise is in the areas of networked
multimedia systems, real-time voice and video communication, and low-latency media streaming over the wire-line and wireless
networks. Currently holding positions at Qualcomm CDMA Technologies, San Diego, CA, he is responsible for video and multimedia
system design and development for Qualcomm's mobile station modem (MSM) chipsets. From 2000 to 2001, he conducted research
with Netergy Networks, Inc., Santa Clara, CA, on voice over IP systems that provide improved quality over best-effort networks.
From 2001 to 2003, he had been the lead of the Stanford - Hewlett-Packard Labs low-latency video streaming project, in which
he and his colleagues developed error-resilience techniques for rich media communication over IP networks at low latency.
In the summer of 2002 at Hewlett-Packard Labs, Palo Alto, CA, he developed an accurate loss-distortion model for compressed
video and contributed in the development of the mobile streaming media content delivery network (MSM - CDN) that delivers
rich media over 3G wireless. Yi Liang received the B. Eng. degree from Tsinghua University, Beijing, China.
Eric Setton received the B.S. degree from Ecole Polytechnique, Palaiseau, France in 2001 and the M.S. degree, in Electrical Engineering
from Stanford University in 2003. He is currently a Ph.D. candidate in the department of Electrical Engineering of Stanford
University and is part of the Image, Video and Multimedia Systems group. Multimedia communication over wired and wireless
networks, video compession and image processing are his main research interests. In 2001, he received the Carnot fellowship
and the SAP Stanford Graduate fellowship. In 2003, he received the Sony SNRC fellowship. He has spent time in industry in
France at SAGEM and in the United States at HP labs and at Sony Electronics. He has 4 patents pending.
Bernd Girod is Professor of Electrical Engineering in the Information Systems Laboratory of Stanford University, California. He also
holds a courtesy appointment with the StanfordDepartment of Computer Science and he serves as Director of the Image Systems
Engineering Program at Stanford. His research interests include networked media systems, video signal compression and coding,
and 3-d image analysis and synthesis. He received his M.S. degree in Electrical Engineering from Georgia Institute of Technology,
in 1980 and his Doctoral degree “with highest honours” from University of Hannover, Germany, in 1987. Until 1987 he was a
member of the research staff at the Institut fur Theoretische Nachrichtentechnik und Informationsverarbeitung, University
of Hannover, working on moving image coding, human visual perception, and information theory. In 1988, he joined Massachusetts
Institute of Technology, Cambridge, MA, USA, first as a Visiting Scientist with the Research Laboratory of Electronics, then
as an Assistant Professor of Media Technology at the Media Laboratory. From 1990 to 1993, he was Professor of Computer Graphics
and Technical Director of the Academy of Media Arts in Cologne, Germany, jointly appointed with the Computer Science Section
of Cologne University. He was a Visiting Adjunct Professor with the Digital Signal Processing Group at Georgia Institute of
Technology, Atlanta, GA, USA, in 1993. From 1993 until 1999, he was Chaired Professor of Electrical Engineering/Telecommunications
at University of Erlangen-Nuremberg, Germany, and the Head of the Telecommunications Institute I, co-directing the Telecommunications
Laboratory. He has served as the Chairman of the Electrical Engineering Department from 1995 to 1997, and as Director of the
Center of Excellence “3-D Image Analysis and Synthesis” from 1995-1999. He has been a Visiting Professor with the Information
Systems Laboratory of Stanford University, Stanford, CA, during the 1997/98 academic year. As an entrepreneur, Prof. Girod
has worked successfully with several start-up ventures as founder, investor, director, or advisor. Most notably, he has been
a co-founder and Chief Scientist of Vivo Software, Inc., Waltham, MA (1993–98); after Vivo's aquisition, 1998-2002, Chief
Scientist of RealNetworks, Inc. (Nasdaq: RNWK); and, from 1996–2004, an outside Director of 8 × 8, Inc. (Nasdaq: EGHT). Prof.
Girod has authored or co-authored one major text-book, two monographs, and over 250 book chapters, journal articles and conference
papers in his field, and he holds about 20 international patents. He has served as on the Editorial Boards or as Associate
Editor for several journals in his field, and is currently Area Editor for Speech, Image, Video and Signal Processing of the
“IEEE Transactions on Communications.” He has served on numerous conference committees, e.g., as Tutorial Chair of ICASSP-97
in Munich and ICIP-2000 in Vancouver, as General Chair of the 1998 IEEE Image and Multidimensional Signal Processing Workshop
in Alpbach, Austria, and as General Chair of the Visual Communication and Image Processing Conference (VCIP) in San Jose,
CA, in 2001.
Prof. Girod has been a member of the IEEE Image and Multidimensional Signal Processing Committee from 1989 to 1997 and was
elected Fellow of the IEEE in 1998 ‘for his contributions to the theory and practice of video communications.’ He has been
named ‘Distinguished Lecturer’ for the year 2002 by the IEEE Signal Processing Society. Together with J. Eggers, he is recipient
of the 2002 EURASIP Best Paper Award. 相似文献
137.
介绍了安规测试系统的结构组成及功能实现。该系统的设计可减少测试工位以提高工作效率。使管理者实时了解生产状态,并能对生产线±:所有检测数据自动编码存储分析.数据自动上传公司服务器或商检局系统。 相似文献
138.
极紫外光子计数成像仪图像快显系统设计与实现 总被引:1,自引:0,他引:1
为实现极紫外光子计数成像仪数字图像的实时获取,设计图像快显系统,完成数据的实时传输和图像的快速显示。设计了基于USB2.0的数据传输单元完成成像仪与PC工作机之间的数据交互,介绍了数据传输单元的工作原理与组成,采用FPGA+USB控制芯片的结构实现安全、高效的数据传输。对极紫外光子计数成像仪成像原理进行分析,在PC机中进行数据处理,完成图像的快速显示,实现极紫外光子计数成像仪的实时图像测试。经实验验证,本系统可以完成科学数据的实时接收与图像的快速显示功能,满足设备的调试与测试需求。 相似文献
139.
视频在无线易错信道上传输,报文丢失会导致图像质量显著下降。多参考帧选择方法可以降低误码扩散,从而提高误码信道上传输视频的图像质量。但是参考帧选择方法也使得编码器计算复杂度大大增加。基于多参考帧选择技术提出一种低复杂度的率失真优化方法。该方法首先在编码器上重建误码图像,使得编码器和解码器上的参考图像一致,然后利用端到端率失真优化模型,在重建的误码图像与编码图像的上一帧图像中选择最优的参考帧。在进行率失真计算时,采用线性预测方法计算运动补偿后图像差值的方差,减少了运动估计运算,从而大大降低计算复杂度。实验结果表明相对于帧内刷新方法该方法显著提高图像质量,相对于一般多参考帧选择方法,在损失很小性能的情况下,大大降低了计算复杂度。 相似文献
140.
Benhui Yang Hongming Yin Keli Han Shiliang Ding 《International journal of quantum chemistry》2001,81(3):214-221
We report the study of translational‐vibrational energy transfer in the A+BC scattering using the dynamical Lie algebraic approach combined with the intermediate picture. The rotational sudden approximation is applied to treat the rotational motion of the BC molecule, which is regarded as an anharmonic oscillator. The calculated results show that the transition probabilities increase with increasing rotational quantum number. Comparison with those obtained in the collinear collision of system A+BC manifests that the transition probabilities here increase indeed. © 2001 John Wiley & Sons, Inc. Int J Quant Chem 81: 214–221, 2001 相似文献