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High Performance Speech Compression System

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Journal of University of Science and Technology beijing 2001年第3期8卷 229-233页

作者： Ke Liu, Zhichun Mu, Zhong Wang information Engineering School, University of Science & Technology beijing, beijing 100083.{3. Univ Sci & Technol beijing Informat Engn Sch Beijing 100083 Peoples R China

Since Pulse Code Modulation emerged in 193., digitized speech has experienced rapid development due to its outstanding voice quality, reliability, robustness and security in communication. But how to reduce channel width without loss of speech quality remains a crucial problem in speech coding theory. A new full-duplex digital speech communication system based on the Vocoder of AMBE-1000(TM) and microcontroller ATMEL 89C51 is introduced. It shows higher voice quality than current mobile phone system with only a quarter of channel width needed for the latter. The prospective areas in which the system can be applied include satellite communication, IP Phone, virtual meeting and the most important, defence industry.

关键词： digital signal processing digital speech compression digital communication full-duplex coding rate

Transmembrane protein VSD is required for axon crossing for the formation of central complex

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Transmembrane protein VSD is required for axon crossing for ...

A Practical Reconstruction Algorithm in 2D Industrial CT

中国神经科学学会第九届全国学术会议暨第五次会员代表大会

作者： Xue-Bo CHENG,Hai-Yun GONG,Zhe-Feng GONG,Li LIU~* State Key laboratory of Brain and Cognitive Science,Institute of biophysics,chinese {3. of {4.,beijing 100101,china

＜正＞Objective Neuronal connections between the hemispheres are considered important for organisms to organize information to adapt to variable *** central complex split flies,the locomotor activity and the visual learning and memory are *** midline crossing is an event that requires many components to regulate each *** study is aimed to find the genes that affect the formation of central *** Histochemistry with antibody nc82 was used to observe the shape of central *** blot with anti- vsd specific antibodies were used to study the characteristic of the ***（1） Nonsense mutation in the extracellular domain of VSD contributed to the central complex defect.（2） VSD can be cleaved by an unknown protease and release the intracellular domain from the membrane.（3. Overexpression the extracellular domain of NRG can partially rescue the mutant phenotype caused by knockdown of *** Transmembrane protein VSD （visual system disorganization） is essential for the formation of the central complex and NRG cooperates with VSD to regulate the axon midline crossing.

关键词： Drosophila melanogaster,central complex histochemistry transmembrane protein

来源： cnki会议评论

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中国体视学与图像分析 2005年第3期 189-193页

作者： LI Hui 1,2, TIAN Jie 2, ZHANG ZhaoTian 3.(1. Department of Education Technology, Capital Normal University, beijing, 10003., china 2. Medical Image processing Group, Key {3. of Complex Systems and Intelligence Science, Institute of Automation, {4. academy of sciences, P.O.Box 2728, beijing, 100080, china 3. Department of information Science, National Natural Science Foundation of china, beijing, 100085, china)

Computed tomography plays an important role in industrial non-destructive testing, medical applications, astronomy and many other fields to look inside the scanned object and to analysis its inner structures. A non-destructive testing software have been developed to efficiently detect inner flaws of space industrial components. As the core of our software, reconstruction algorithms including preprocess of raw data, re-arrange algorithm and filtered back-projection algorithms have been described in detail in this article. With real raw data from CASC of china, experimental results verified the applied reconstruction algorithm in our software. Furthermore, forward algorithms simulating generation of fan-beam raw data are also presented in this article.

关键词： Reconstruction algorithms industrial CT imaging data preprocess

Spatio-temporal pattern analysis of single-trial EEG signals recorded during visual object recognition

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Science china(information sciences) 2011年第12期54卷 2519-2527页

作者： WANG ChangMing 1 , HU XiaoPing 3., YAO Li 1,2 , XIONG Shi 2 & ZHANG JiaCai 2 1 National Key laboratory of Cognitive Neuroscience and Learning, beijing Normal University, beijing 100875,{3. 2 College of {4. Science and Technology, beijing Normal University, beijing 100875,{3. 3.Biomedical Imaging Technology Center, Emory University/Georgia Institute of Technology, Atlanta 3.3.2, USA 1. National Key laboratory of Cognitive Neuroscience and Learning Beijing Normal University Beijing 100875 China3. Biomedical Imaging Technology Center Emory University/Georgia Institute of Technology Atlanta 30322 USA2. College of Information Science and Technology Beijing Normal University Beijing 100875 China

Object discrimination is a fundamental cognitive function for human brains. In this study, we utilized an analysis approach for single-trial electroencephalography (EEG) to analyze the spatio-temporal activation patterns of visual objects processing in human brains, and attempted to apply it to discriminate different visual objects. The spatial patterns were respectively extracted from scalp EEG and the reconstructed cortical sources, while the experiment participants were perceiving {3.different categories of visual objects (faces, buildings, cats and cars). By classifying the patterns extracted from single-trial EEG, the presented visual objects could be discriminated by a computer, and the classification accuracies may provide a quantitative index to evaluate the spatial differences of the brain activations related to different visual objects. Our results demonstrated that the spatial patterns on both the scalp and the sources levels resulted in higher classification accuracies than chance rate. We also examined the classification results using temporally non-overlapping time intervals of different event-related potential (ERP) components. The temporal changes of classification accuracies may reflect the temporal distribution of the discriminative information in the EEG responses. The present pattern extraction and classification methods may compose a computational model for single-trial EEG data analysis in investigations of the spatio-temporal activation patterns for object recognition. These spatio-temporal patterns in EEG may be useful to identifying the discriminative spatial areas and time stages to improve the accuracies and efficiencies of object discrimination. In addition, investigating and utilizing humans'cognitive mechanisms of object recognition may improve computers' processing efficiency of visual information.

关键词： EEG spatio-temporal pattern object recognition single-trial analysis visual information processing

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零磁空间对金黄仓鼠脑中几种神经递质的影响

生物化学与生物物理进展 2001年第3期28卷 358-361页

作者：李俊凤吴奇久王倩蒋锦昌金海强林云芳中国科学院生物物理研究所国家地震局地球物理研究所北京100081

对饲养在近零磁空间 (MFFS)不同时间的金黄仓鼠大脑皮层、基底核和小脑中氨基酸类抑制性神经递质γ 氨基丁酸 (GABA)、甘氨酸 (glycine)及牛磺酸 (taurine)的含量进行了测定 .与正常地磁环境下饲养的动物相比 ,随着时间的推移 ,这几种... 详细信息

对饲养在近零磁空间 (MFFS)不同时间的金黄仓鼠大脑皮层、基底核和小脑中氨基酸类抑制性神经递质γ 氨基丁酸 (GABA)、甘氨酸 (glycine)及牛磺酸 (taurine)的含量进行了测定 .与正常地磁环境下饲养的动物相比 ,随着时间的推移 ,这几种递质在皮层中的含量变化不明显 ,在一个月后 ,基底核和小脑中GABA含量逐渐降低 ,而小脑中一个月后tau的含量却表现出逐渐升高的趋势 .这些递质的含量变化情况与某些神经疾病患者相应脑区这几种递质的变化表现出类似的规律 .

关键词：零磁空间小脑基底核脑皮层甘氨酸牛磺酸 γ-氨基丁酸仓鼠神经递质

Implantable CMOS neuro-stimulus chip for visual prosthesis

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Science china(information sciences) 2011年第4期54卷 898-908页

作者： ZHANG Xu 1,PEI WeiHua 1,HUANG BeiJu 1,WANG ShuJing 1,GUAN Ning 1,GUO Kai 1,WANG Yu 1,GUI Qiang 1,CHEN Jin 1,WANG Kai 2,WU HuiJuan 2,LI XiaoXin 2,LI Kai 3.& CHEN HongDa 1 1 State Key laboratory on Integrated Optoelectronics,Institute of Semiconductors,chinese academy of {3.,{4. 100083.china 2 Department of Ophthalmology,People’s Hospital of Peking University,{4. 10004.,china 3.Department of Epidemiology and Biostatistics,Health Science Center,Peking University,{4. 100083.china 1. State Key laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China2. Department of Ophthalmology People’s Hospital of Peking University Beijing 100044 China3. Department of Epidemiology and Biostatistics Health Science Center Peking University Beijing 100083 China

A prototype chip with 2×2 pixels for implanting in blind patients affected by outer retinal degeneration is presented in this *** visual prosthesis chip imitates the degenerated photoreceptor cells,senses the incident light and stimulates the remaining healthy layers of retina or optic *** pixel integrates photodiode and stimulus pulse generator,converting the illumination on the eyes into 3.bit resolution bi-phasic current ***-chip charge cancellation modules are used to discharge each electrode site for tissue *** prototype chip is designed and fabricated in 0.18-μm N-well CMOS (complementary metal oxide semiconductor) 1P6M Mix-signal process,with a ±2.5 V dual voltage *** functionality of the fabricated chip is demonstrated on anesthetized *** responses in visual cortex are successfully evoked by the neuro-stimulus chip through an on-board trigger interface and flexible electrode.

关键词： biomedical microelectronics visual prosthesis functional electrical stimulation acute animal ex- periment electrical evoked potential (EEP) test

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汉语自动分词的研究现状与困难

系统仿真学报 2005年第1期17卷 138-143,147页

作者：张春霞郝天永中国科学院计算技术研究所

汉语自动分词是信息提取、信息检索、机器翻译、文本分类、自动文摘、语音识别、文本语音转换、自然语言理解等中文信息处理领域的基础研究课题。尽管已被研究了二十多年,分词仍然是中文信息处理的瓶颈问题。基于对汉语自动分词研究的... 详细信息

汉语自动分词是信息提取、信息检索、机器翻译、文本分类、自动文摘、语音识别、文本语音转换、自然语言理解等中文信息处理领域的基础研究课题。尽管已被研究了二十多年,分词仍然是中文信息处理的瓶颈问题。基于对汉语自动分词研究的现状分析,构建了自动分词的形式化模型,论述了影响分词的诸多因素,分析了分词中存在的两个最大困难及其解决方法。最后指出了目前分词研究中尤其是在分词评测方面存在的问题以及未来的研究工作。

关键词：汉语自动分词形式化模型未登录词分词评测

SAR image despeckling based on edge detection and nonsubsampled second generation bandelets

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Journal of Systems Engineering and Electronics 2009年第3期20卷 519-526页

作者： Zhang Wenge~(1,2),Liu Fang~(1,2),Jiao Licheng~(2,3.& Gao Xinbo~(2,3. 1.School of Computer Science and Technology,Xidian Univ.,Xi’an 710071,P.R.china 2.Key Lab.of Intelligent Perception and Image Understanding of Ministry of Education of china,Xi’an 710071,P.R.china 3.Inst,of Intelligent {3. {4.,Xidian Univ.,Xi’an 710071,P.R.china School of Computer Science and Technology Xidian Univ. Xi'an 710071 P. R. China Key Lab. of Intelligent Perception and Image Understanding of Ministry of Education of china Xi'an 710071 P. R. China Key Lab. of Intelligent Perception and Image Understanding of Ministry of Education of china Xi'an 710071 P. R. China Inst. of Intelligent information processing Xidian Univ. Xi'an 710071 P. R. China

To preserve the sharp features and details of the synthetic aperture radar （SAR） image effectively when despeckling, a despeckling algorithm with edge detection in nonsubsampled second generation bandelet transform （NSBT） domain is proposed. First, the Canny operator is utilized to detect and remove edges from the SAR image. Then the NSBT which has an optimal approximation to the edges of images and a hard thresholding rule are used to approximate the details while despeckling the edge-removed image. Finally, the removed edges are added to the reconstructed image. As the edges axe detected and protected, and the NSBT is used, the proposed algorithm reaches the state-of-the-art effect which realizes both despeckling and preserving edges and details simultaneously. Experimental results show that both the subjective visual effect and the mainly objective performance indexes of the proposed algorithm outperform that of both Bayesian wavelet shrinkage with edge detection and Bayesian least square-Gaussian scale mixture （BLS-GSM）.

关键词： computer image processing synthetic aperture radar speckle edge detection nonsubsampled second generation bandelet transform Canny operator threshold shrinkage.

New method for measuring the degree of conflict among general basic probability assignments

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Science china(information sciences) 2012年第2期55卷 312-321页

作者： HE You1,HU LiFang1,2,GUAN Xin1,3.DENG Yong4.& HAN DeQiang5 1Research Institute of information Fusion,Naval Aeronautical and Astronautical University,Yantai 264.01,{3. 2Navy Armament academy,beijing 10224.,{3. 3.he Institute of Electronic Science and Engineering,National University of Defense Technology,Changsha 4.0073.{3. 4.chool of Electronics and information Technology,Shanghai Jiao Tong University,Shanghai 20024.,{3. 5Institute of Integrated Automation,Xi'an Jiaotong University,Xi'an 71004.,{3. 1. Research Institute of information Fusion Naval Aeronautical and Astronautical University Yantai 264001 China2. Navy Armament Academy Beijing 102249 China3. The Institute of Electronic Science and Engineering National University of Defense Technology Changsha 410073 China4. School of Electronics and Information Technology Shanghai Jiao Tong University Shanghai 200240 China5. Institute of Integrated Automation Xi’an Jiaotong University Xi’an 710049 China

There is doubt about Dempster's rule of combination because of counter-intuitive results when dealing with conflict information in intelligent ***,many modified combination rules have been presented in the literature on multi-source information fusion and reasoning with ***,the issue of identifying conflict among evidence has been ignored.A new parameter measuring conflict evidence called the conflict distance parameter is defined to determine whether there are conflicts in evidence based on the analysis of existing conflict *** the same time,a decisive rule,which a reasonable conflict measure function should satisfy,is put ***,an analysis of two typical counter-intuitive situations is given,showing that the new parameter can not only satisfy the decisive rule,but can also attain the same effect as a two-dimensional measure when deciding whether to use the Dempster's rule of combination,and can exceed its effect when deciding whether to use Dezert-Smarandache theory.

关键词： conflict evidence Dezert-Smarandache theory Dempster’s rule of combination information fusion uncertainty