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A Cumulant-Based Adaptive detection.Technique for Optical Wireless Communication Over Strong Turbulence Channels

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China Communications 2008年第1期5卷 22-27页

作者： Wang, Jin Huang, Dexiu Yuan, Xiuhua Huazhong Univ Sci & Technol Wuhan Natl Lab Optoelect Wuhan 430074 Peoples R China

The optical wireless communication (OWC) is afading channel because of the effect of atmosphericattenuation. We introduce a cumulant-based adaptive detection.technique to providehigh performance for OWC. The received signalof OWC over strong turbulence channels is assumedto be a mixture of K-distributed fading andGaussian distributed thermal noise. In order tomitigate the fading induced by turbulence, thedecision threshold-updating algorithm based onsecond and higher order cumulants is proposed,which is able to operate in an unknown turbulenceenvironment. The performance of the adaptiveprocessing scheme has been evaluated by meansof Monte Carlo simulations. It is shown that theproposed approach proves valuable for a limitednumber K of memory data.

关键词： Optical wireless communication atmospheric turbulence K-distributed adap- tive detection.

Crowd region detection.in outdoor scenes using color spaces

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International Journal of Modeling, Simulation, and Scientific Computing 2018年第2期9卷 55-69页

作者： Huma Chaudhry Mohd Shafry Mohd Rahim Tanzila Saba Amjad Rehman Faculty of Computing University Technology Malaysia 81310 JohorMalaysia College of Computer and Information Sciences Prince Sultan UniversityRiyadh 11586Saudi Arabia College of Computer and Information Systems Al-Yamamah University Riyadh 11512 Saudi Arabia

In the last few decades,crowd detection.has gained much interest from the research community to assist a variety of applications in surveillance *** human detection.in partially crowded scenarios have achieved many reliable works,a highly dense crowdlike situation still is far from being *** crowded scenes offer patterns that could be used to tackle these *** problem is challenging due to the crowd volume,occlusions,clutter and *** region classification is a precursor to several types of *** this paper,we propose a novel approach for crowd region detection.in outdoor densely crowded scenarios based on color variation context and RGB channel *** results are presented to demonstrate the effectiveness of the new color-based features for better crowd region detection.

关键词： Crowd detection color features segmentation detection.

Fabric Defect detection.Using Adaptive Wavelet Transform

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维普期刊数据库

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Journal of Donghua University(English Edition) 2002年第1期19卷 35-39页

作者：李立轻黄秀宝 Coll. of Textiles Dong Hua Univ. Shanghai 200051 China

A method of woven fabric defect detection.using the wavelet transform adaptive to the fabric has been developed. With reference to the orthogonality constrains of Daubechies wavelet, by taking the mmimization of the energy or the gray level of the pixels in the output sub-images as the additional conditions and using the random algorithm method, two sets of wavelet filters adapted to the fabric texture were formed. The original images of normal fabric texture and the fabric texture with defects were decomposed into horizontal and vertical sub- images by using these filters and the feature indices of these sub-images were also extracted. By comparing the feature indices of the normal texture with that of the defective texture, the fabric defects can be successfully detected and located.

关键词： wavelet transform, adaptive wavelet, image decompose, fabric defect detection.

Quantitative detection.of Blood Vessel Structures in MRI by Using 3-D Geometrical Moments

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Chinese Science Bulletin 1994年第9期39卷 785-789页

作者：罗立民谢筱华鲍旭东 Jean-Louis Coatrieux Department of Biology and Medical Engineering Southeast University Nanjing 210018 PRC Laboratoire Traitement du Signal et de L'Image University of Rennes-Ⅰ35042 RennesFrance

The quantitative analysis of three-dimensional (3-D) human blood vessel structuresplays a very important role in the clinical diagnosis. The conventional X-ray approacheshave some shortcomings, such as the need to make use of a dye-product and basisprojective-integrative rule for the image formation. On the one hand, the patient hasto suffer a great radiation dose, and a registration process is also often needed to cor-rect the displacement bias between the images due to the patient’s movements. On

关键词： blood vessel moments quantitative detection.

RAPID detection.OF EXOGENOUS HUMAN CLOTTING FACTOR IX cDNA IN TRANSFERRED CELLS BY POLYMERASE CHAIN REACTION

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Chinese Science Bulletin 1990年第23期35卷 1995-1999页

作者：周洁民戴一凡邱信芳薛京伦 Institute of Genetics Fudan University Shanghai 200433 PRC

Polymerase chain reaction (PCR) is a recently devoloped molecular biological technique, using specific oligonucleotide primers and DNA polymerase to amplify the specific fragment of DNA in vitro. This technique has been successfully introduced in gene diagnosis, mutation detection. polymorphism analysis and nucleotide sequencing. In the study of gene transfer and gene therapy, it is necessary to analyse DNA in the

关键词： polymerase chain reaction human clotting factor Ⅸ cDNA exogenous cDNA detection.

Approach to Quantitative detection.of CD146 with a Label-free Protein Biosensor Based on Imaging Ellipsometry

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生物物理学报 2009年第S1期25卷 300-301页

作者： Yu Niu1, Ying Zhang2, 3, Xiyun Yan2, Gang Jin 1 Institution of mechanics, Chinese academy of Sciences, Beijing, China 2 Institution of biophysics, Chinese academy of Sciences, Beijing, China 3 Institution of biophysics, Chinese academy of Sciences, Beijing, China Institution of mechanics, Chinese academy of Sciences, Beijing, China

CD146 glycoprotein, belonging to the immunoglobulin gene superfamily, plays a unique role in heterophilic cell-cell interactions as a calcium ions independent cell adhesion

关键词： biosensor protein micro-array Imaging ellipsometry CD146 detection.

Ultra-low frequency passive vertical vibration isolation system

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Science China Mathematics 1999年第6期42卷 660-665页

作者：赵鹏飞罗俊周泽兵唐家祥 Department of Physics Huazhong University of Science and Technology Wuhan China Department of Civil Engineering Huazhong University of Science and Technology Wuhan China

An ultra-low frequency passive vertical vibration isolator is constructed by mounting a couple of additional masses on the crank-arms of the torsion spring. The theoretical analysis and experimental results show that the system with additional masses can achieve better vertical vibration isolation and longer resonant period. Measured displacement response of the test mass under seismic excitation reaches 3 x 10-12 m/√ Hz around 10 Hz, and the isolation ratio comes to about 60 dB attenuation at 6 Hz, which is about 30 dB lower than that of the system without additional masses.

关键词： vertical vibration isolation torsion spring isolation ratio resonant period gravitational wave detection.

Active damping system with respect to quasi-fixed reference

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Science China Mathematics 1999年第12期42卷 1301-1307页

作者：范淑华周泽兵唐家祥罗俊 Department of Physics Huazhong University of Science and Technology Wuhan China Department of Civil Engineering Huazhong University of Science and Technology Wuhan China

A vertical quasi-fixed reference system is constructed using a torsion spring, and the vertical normal mode of a single-stage isolator is successively damped with respect to the quasi-fixed reference system. The experimental result shows that the vertical normal mode was damped from 3×10?8/ $\sqrt {Hz} $ down to 2×10?9/ $\sqrt {Hz} $ without reintroducing the high frequency ground vibration. This agrees well with the theoretical analyses.

关键词： active damping quasi-fixed reference system feedback control gravitational wave detection.

Vibration mode of torsion balance and its response to external shock

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Science China Mathematics 1997年第5期40卷 515-521页

作者：汤洁罗俊范淑华 Huazhong University of Science and Technology Wuhan 430074 China

Intrinsic vibration modes of typical torsion balances and their response to the external shock are discussed in detail. The study is important and instructive for improving measurement precision of gravitational experiments employing torsion balances, and gives a reasonable interpretation on detecting earthquake by high precision torsion balance.

关键词： torsion balance vibration mode shock earthquake detection.