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Computer simulation on reliability of retention index with FDG-PET and optimization of dual-time-point imaging protocol

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Progress in Natural Science:Materials International 2008年第8期18卷 931-937页

作者： Rui Jia a, Jing Bai a,*, Lingfeng Wenb,c, Dagan Fengb,c a department of Biomedical engineering, Tsinghua university, Room B209, Building of Medical Science, {3. 100084. China b School of {4. Technologies, university of Sydney, NSW 2006, Australia c department of electronic and {4. engineering, Hong Kong Polytechnic university, Hong Kong department of Biomedical engineering Tsinghua University Room B209 Building of Medical Science Beijing 100084 China School of information Technologies University of Sydney NSW 2006 Australia department of electronic and information {3. Hong Kong Polytechnic University Hong Kong

The inherent noise in positron emission tomography (PET) leads to the instability of quantitative indicators, which may affect the diagnostic accuracy for differentiating malignant and benign lesions in the management of lung cancer. In this paper, the reliability of retention index (RI) is systematically investigated by using computer simulation for the dual-time-point imaging protocol. The area under the receiver operating characteristic (ROC) curve is used to evaluate the optimal protocol. Results demonstrate that the reliability of RI is affected by several factors including noise level, lesion type, and imaging schedule. The RIs with small absolute values suffer from worse reliability than those larger ones. The results of ROC curves show that over delayed second scan cannot help to improve the diagnostic performance further, while an early first scan is expected. The method of optimization based on ROC analysis can be easily extended to comprise as many lesions as possible.

关键词： Reliability Retention index PET (positron emission tomography) Simulation ROC (receiver operating characteristic)

A Review of Speech Coding

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通信学报 1998年第5期19卷 45-56页

作者： Bao ChangchunAssociate professor of information engineering, beijing Polytechnic {3., Ph.D, CIE senior member ({4. of electronic engineering, beijing Polytechnic {3., beijing 100022) Fan ChangxinProfessor with Xidian {3., C

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关键词：语音编码线性估计综合分析波形编码

Sequence-based localization algorithm with improved correlation metric and dynamic centroid

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Science China(information Sciences) 2011年第11期54卷 2349-2358页

作者： YU Ying 1,JIANG ChunXiao 2,ZHAO XiaoJie 2,YUN LiJun 1,LI ZhiHua 2 & REN Yong 21 college of information,Yunnan Normal university,Kunming 650500,China 2 {3. of {4. engineering,Tsinghua university,beijing 100084.China 1. college of information Yunnan Normal University Kunming 650500 China2. Department of Electronic Engineering Tsinghua University Beijing 100084 China

Ecolocation (error controlling localization technique) is a novel sequence-based RF localization algorithm.A key feature of the Ecolocation algorithm is that it constructs a constraint table based on RSSI values and compares data between two ***,the definitions of the constraint and the centroid in the Ecolocation algorithm are imperfect,and result in poor localization *** improve the localization accuracy,a new algorithm based on weighted rank order correlation coefficient and dynamic centroid method is *** results indicate that compared with the Ecolocation,the localization accuracy and robustness of the new algorithm are distinctly raised.

关键词： WSNs (wireless sensor networks) localization sequences constraint table rank order correlation coefficient

Feature combination for classifying single-trial ECoG during motor imagery of different sessions

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Progress in Natural Science:Materials International 2007年第7期17卷 851-858页

作者： Wei Qingguo~(1,2) Meng Fei~1 Wang Yijun~1 Gao Xiaorong~1 Gao Shangkai~(1**) (1.department of Biomedical engineering,School of Medicine,Tsinghua university,{3. 100084.China 2.department of electronic engineering,School of information,Nanchang university,Nanchang 3.0029,China) [a]department of Biomedical engineering School of Medicine TsinghuaUniversity Beijing China [b]department of electronic engineering School of Information Nanchang University Nanchang China

The input signals of brain-computer interfaces(BCIs)may be either scalp electroencephalogram(EEG)or electrocor- ticogram(ECoG)recorded from subdural *** make BCIs practical,the classifiers for discriminating different brain states must have the ability of session-to-session *** paper proposes an algorithm for classifying single-trial ECoG during motor imagery of different *** features,derived from two physiological phenomena,movement-related potentials(MRP)and event-related desynchronization(ERD),and extracted by common spatial subspace decomposition(CSSD)and waveform mean,are combined to per- form classification *** specific signal processing methods utilized are described in *** algorithm was successfully applied to Data SetⅠof BCI CompetitionⅢ,and achieved a classification accuracy of 91% on test set.

关键词： brain-computer interface(BCI) electrocorticogram(ECoG) session-to-session transfer feature combination movement-related potentials(MRP) event-related desynchronization(ERD)

Study on internal quantum efficiency of blue InGaN multiple-quantum-well with an InGaN underneath layer

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Science China(Technological Sciences) 2010年第2期53卷 306-308页

作者： WANG JiaXing, WANG Lai, ZHAO Wei, ZOU Xiang & LUO Yi National Laboratory for information Science and Technology/State Key Laboratory on Integrated Optoelectronics, department of electronic {4., Tsinghua university, beijing 100084. China 1. National Laboratory for information Science and Technology/State Key Laboratory on Integrated Optoelectronics Department of Electronic Engineering Tsinghua University Beijing 100084 China

Blue InGaN multiple-quantum-well (MQW) samples with different InxGa1-xN (x=0.01–0.04. underneath layers (ULs) were grown by metal organic vapor phase epitaxy (MOVPE). Temperature dependent photoluminescence showed that the InGaN UL can improve the internal quantum efficiency (IQE) of MQW effectively due to strain release. And a maximum IQE of 50% was obtained when the thickness and In content of the InGaN UL were 60 nm and 0.01, respectively. Furthermore, the larger In content or thickness of the InGaN UL makes the IQE lower. Arrhenius fit to the experiment data showed that the IQE fall was mainly caused by the quantity increase of the nonradiative recombination centers, which was believed related to the accumulated stress in InGaN ULs.

关键词： InGaN underneath layer (UL) multiple-quantum-well (MQW) internal quantum efficiency (IQE) Arrhenius formula

Perturbed solution of sea-air oscillator for the El Nino/ La Nina-Southern Oscillation mechanism

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Acta Oceanologica Sinica 2009年第3期28卷 1-4页

作者： ZHOU Xianchun LIN Yihua WANG Hui MO Jiaqi college of electronic and information {3. Nanjing University of information Science and Technology Nanjing 210044 China Division of Computational Science E-Institutes of Shanghai Universities at SJTU Shanghai 200240 China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China National Marine Environmental Forecastins Center Beijing 100081 China department of Mathematics Anhui Normal University Wuhu 241000 China

A class of coupled system of the E1 Nino/La Nina-Southern Oscillation （ENSO） mechanism is studied. Using the perturbed theory, the asymptotic expansions of the solution for ENSO model are obtained and the asymptotic... 详细信息

关键词： nonlinear perturbation theory E1 Nino/La Nina-Southern Oscillation model

Mapping and overlapping based carrier frequency searching technique for rapid GNSS long PN-code acquisition

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Science China(information Sciences) 2010年第12期53卷 2642-2652页

作者： LI Hong ,LU MingQuan & FENG ZhenMing department of electronic engineering,Tsinghua {3.,{4. 100084.China 1. department of electronic engineering Tsinghua University Beijing 100084 China

In global navigation satellite systems(GNSS),because of the long period and high chip rate of long pseudo-noise(PN) code,the rapid acquisition is hard to *** speed up search process,in the paper,a mapping and overlapping based carrier frequency searching technique is *** mapping incoming signals of the same interval to different carrier frequency cells and overlapping together the mapped incoming signals that correspond to the same code phase,the technique reduces the number of the cells to be *** effect of the technique on detection and mean acquisition time performance is *** is shown that the technique reduces the cells to be searched and shortens mean acquisition time at the expense of degrading detection *** technique is fit to the previously published acquisition methods and is capable of improving their mean acquisition time *** and simulation results validate the analysis.

关键词： carrier frequency cells mapping overlapping acquisition performance

Performance Analysis of Two CFAR Detectors in Clutter Edge Situation

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Journal of Systems engineering and electronics 2001年第2期12卷 44-51页

作者： He You department of electronic engineering, Naval Aeronautical engineering Academy Yantai 264.01, P. R. China Guan Jian department of electronic engineering, Tsinghua university, beijing 100084. R R. China department of electronic engineering Naval Aeronautical Engineering Academy Yantai 264001 P. R. China department of electronic engineering Tsinghua University Beijing 100084 P. R. China

This paper studies the performance of the GOSGO and GOSSO CFAR detectors [1] in clutter edge situation. The authors derive the analytic expressions of the false alarm probabilities in that situation, analyze their performances against clutter edge, and compare them with the OS, CA, GO and SO detectors. The results show that GOSGO possesses better performance than GO for countering clutter, but the performance of GOSSO is very unideal.

关键词： Alarm systems Clutter (information theory) Gaussian noise (electronic) Signal to noise ratio White noise

The Application of Fuzzy-Neural Network on Control Strategy of Hybrid Vehicles

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The Application of Fuzzy-Neural Network on Control Strategy ...