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Content subscribing mechanism in P2P streaming based on gamma distribution prediction

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 1983-1989页

作者： GUO Tong-qiang WENG Jian-guang zhuang yue-ting School of Computer Science Zhejiang University Hangzhou 310027 China

P2P systems are categorized into tree-based and mesh-based systems according to their topologies. Mesh-based systems are considered more suitable for large-scale Internet applications, but require optimization on latency issue. This paper proposes a content subscribing mechanism (CSM) to eliminate unnecessary time delays during data relaying. A node can send content data to its neighbors as soon as it receives the data segment. No additional time is taken during the interactive stages prior to data segment transmission of streaming content. CSM consists of three steps. First, every node records its historical segments latency, and adopts gamma distribution, which possesses powerful expression ability, to express latency statistics. Second, a node predicts subscribing success ratio of every neighbor by comparing the gamma distribution parameters of the node and its neighbors before selecting a neighbor node to subscribe a data segment. The above steps would not increase latency as they are executed before the data segments are ready at the neighbor nodes. Finally, the node, which was subscribed to, sends the subscribed data segment to the subscriber immediately when it has the data segment. Experiments show that CSM significantly reduces the content data transmission latency.

关键词：国际互联网分布特点流动特点 P2P技术

Audio steganalysis based on “negative resonance phenomenon” caused by steganographic tools

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第4期7卷 577-583页

作者： RU Xue-min zhuang yue-ting WU Fei Institute of Artificial Intelligence Zhejiang University Hangzhou 310027 China

Researching on the impact different steganographic software tools have audio statistical features, revealed the phe- nomenon that when messages are embedded in a WAV file by using a certain tool, the variation of statistical features in the WAV file which already contains messages embedded by the same tool is abruptly smaller than those in which messages have not been embedded. We call it “negative resonance phenomenon” temporarily. With the phenomenon above and Support Vector Machines (SVMs), we can detect the existence of hidden messages, and also identify the tools used to hide them. As shown by the experi- mental results, the proposed method can be very effectively used to detect hidden messages embedded by Hide4PGP, Stegowav and S-Tools4.

关键词：支撑向量机线性预报共振 SVM 视听设备

Multi-sensor image registration using multi-resolution shape analysis

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第4期7卷 549-555页

作者： YUAN Zhen-ming WU Fei zhuang yue-ting School of Computer Science and Technology. Zhejiang University Hangzhou 310027 China School of Information Engineering Hangzhou Teacher＇s College Hangzhou 310036 China

Multi-sensor image registration has been widely used in remote sensing and medical image field, but registration performance is degenerated when heterogeneous images are involved. An image registration method based on multi-resolution shape analysis is proposed in this paper, to deal with the problem that the shape of similar objects is always invariant. The contours of shapes are first detected as visual features using an extended contour search algorithm in order to reduce effects of noise, and the multi-resolution shape descriptor is constructed through Fourier curvature representation of the contour’s chain code. Then a minimum distance function is used to judge the similarity between two contours. To avoid the effect of different resolution and intensity distribution, suitable resolution of each image is selected by maximizing the consistency of its pyramid shapes. Finally, the transformation parameters are estimated based on the matched control-point pairs which are the centers of gravity of the closed contours. Multi-sensor Landsat TM imagery and infrared imagery have been used as experimental data for comparison with the classical contour-based registration. Our results have been shown to be superior to the classical ones.

关键词：图象配准数据处理形状描述符特征匹配传感器

Data-driven facial animation based on manifold Bayesian regression

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第4期7卷 556-563页

作者： WANG Yu-shun zhuang yue-ting WU Fei School of Computer Science and Technology Zhejiang University Hangzhou 310027 China The Microsoft State Education Ministry Key Laboratory Zhejiang University Hangzhou 310027 China

Driving facial animation based on tens of tracked markers is a challenging task due to the complex topology and to the non-rigid nature of human faces. We propose a solution named manifold Bayesian regression. First a novel distance metric, the geodesic manifold distance, is introduced to replace the Euclidean distance. The problem of facial animation can be formulated as a sparse warping kernels regression problem, in which the geodesic manifold distance is used for modelling the topology and discontinuities of the face models. The geodesic manifold distance can be adopted in traditional regression methods, e.g. radial basis functions without much tuning. We put facial animation into the framework of Bayesian regression. Bayesian approaches provide an elegant way of dealing with noise and uncertainty. After the covariance matrix is properly modulated, Hybrid Monte Carlo is used to approximate the integration of probabilities and get deformation results. The experimental results showed that our algorithm can robustly produce facial animation with large motions and complex face models.

关键词：图象处理面部生气测地距贝叶斯回归数据驱动

Synergistic effects of three traditional herbs green tea,mulberry leaf and corn silk on glucose uptake level of L6 myoblasts and the hypoglycemic mechanism

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Traditional Medicine Research 2024年第7期9卷 1-12页

作者： Jing-Na Zhou Ming-yue Li ting-ting Zhang Jing-Yang Lu Min Zhang Peng-Wei zhuang Hai-Xia Chen Tianjin Key Laboratory for Modern Drug Delivery&High-Efficiency School of Pharmaceutical Science and TechnologyTianjin UniversityTianjin 300072China. School of Food Science and Bioengineering Tianjin Agricultural UniversityTianjin 300384China. State Key Laboratory of Nutrition and Safety Tianjin University of Science&TechnologyTianjin 300457China. Haihe Laboratory of Modern Chinese Medicine Chinese Materia Medica CollegeTianjin University of Traditional Chinese MedicineTianjin 301617China.

Background:Green tea,mulberry leaf and corn silk are traditional herbs used in the prevention and treatment of diabetes in China for a long time,but their synergistic hypoglycemic effects and mechanisms remain ***:The effective components of green tea,mulberry leaf and corn silk were extracted and *** design of experiments was used to study the influences of different combinations on the cell viability and glucose uptake level of L6 myoblasts,so as to determine the optimal synergistic hypoglycemic *** possible hypoglycemic mechanism of the optimal synergistic combination was explored by cytotoxicity assay,glucose uptake assay,and western ***:Three polyphenol enrichment fractions of the herbs,30%ethanol elution fraction of green tea(GT),50%ethanol elution fraction of mulberry leaf(ML)and 60%ethanol elution fraction of corn silk(CS)were *** antioxidant activities of GT-30%,ML-50%and CS-60%were superior to those of crude extracts,and showed strong potential inα-amylase andα-glucosidase inhibition *** optimal synergistic combination of crude extracts G7(crude extract of green tea:crude extract of mulberry leaf:crude extract of corn silk=1:5:3),polyphenol enrichment fractions R3(GT-30%:ML-50%:CS-60%=1:7:1)and monomers X2(epigallocatechin gallate:morusin:formononetin=3:1:2)were selected,respectively.G7,R3,and X2 showed promoting effects on the cell viability and glucose uptake of L6 myoblasts within the detected concentration *** addition,G7,R3,and X2 could increase the expression levels of p-PI3K/PI3K and p-Akt/Akt in L6 myoblasts,and promote the translocation of Glut4,but G7 and R3 showed more significant ***:The synergistic hypoglycemic effects of green tea,mulberry leaf and corn silk had the characteristics of multiple-components and multiple-targets with p-PI3K/PI3K,p-Akt/Akt and the translocation of Glut4 signal pathways *** three traditional herbs might have the potential

关键词： green tea mulberry leaf corn silk synergistic effect type 2 diabetes mellitus mechanism

Ensemble learning HMM for motion recognition and retrieval by Isomap dimension reduction

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第12期7卷 2063-2072页

作者： XIANG Jian, WENG Jian-guang, zhuang yue-ting, WU Fei (School of Computer Science, Zhejiang University, Hangzhou 310027, China) School of Computer Science Zhejiang University Hangzhou China

Along with the development of motion capture technique, more and more 3D motion databases become available. In this paper, a novel approach is presented for motion recognition and retrieval based on ensemble HMM (hidden Markov model) learning. Due to the high dimensionality of motion’s features, Isomap nonlinear dimension reduction is used for training data of ensemble HMM learning. For handling new motion data, Isomap is generalized based on the estimation of underlying eigen- functions. Then each action class is learned with one HMM. Since ensemble learning can effectively enhance supervised learning, ensembles of weak HMM learners are built. Experiment results showed that the approaches are effective for motion data recog- nition and retrieval.

关键词： Feature Isomap HMM (hidden Markov model) Ensemble learning Motion recognition and retrieval

Instantaneous preparation of gold-carbon dot nanocomposites for on-site SERS identification of pathogens in diverse interfaces

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Photonics Research 2024年第6期12卷 1303-1312页

作者： YANXIAN GUO YE LIU CHAOCAI LUO yue ZHANG YANG LI FEI ZHOU ZHOUYI GUO ZHENGFEI zhuang ZHIMING LIU School of Electronic Engineering and Intelligentization Dongguan University of TechnologyDongguan 523808China Department of Physics University of Science and Technology of ChinaHefei 230026China MOE Key Laboratory of Laser Life Science&Guangdong Provincial Key Laboratory of Laser Life Science College of BiophotonicsSouth China Normal UniversityGuangzhou 510631China

Rapid detection of pathogens present on contaminated surfaces is crucial for food safety and public health due to the high morbidity and mortality of bacterial ***,a sensitive and efficient method for on-site identification of foodborne pathogens on anisotropic surfaces was developed by using an in situ instantaneously prepared surface-enhanced Raman scattering(SERS)*** achieve this,molybdenum-doped gallic acid-derived carbon dots(MCDs)are utilized as the reductant for synthesizing Au@MCDs nanohybrids within just 3 s at ambient *** synergistic effect of the electromagnetic enhancement and charge transfer of Au@MCDs enables excellent SERS performance 10 times stronger than bare Au *** bioassay platform requires less than 5 min to complete the quantitative detection of foodborne pathogens on various microbial-contaminated interfaces with a sensitivity of 10 CFU/*** innovative strategy breaks the long-standing limitations of SERS substrates in practical use,such as the time-consuming process,interference of residual surfactants,poor surface stability,and few application scenarios,providing a promising tool for widespread applications in biomedical research and clinical diagnostics.

关键词： temperature. molybdenum consuming

Visual test paper based on Au/δ-MnO_(2) hollow nanosphere oxidase-like activity regulation using hexavalent chromium as a smart switch

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Rare Metals 2024年第2期43卷 711-722页

作者： Wen-Chang zhuang Hai-yue Zhang Zhen-Yang Chen Wen-Jing Cheng Wei-Dan Na Zhao Li Lin Tian School of Materials and Chemical Engineering Xuzhou University of TechnologyXuzhou221018China School of Chemistry and Environmental Science Yili Normal UniversityYining835000China

Paper-based sensing platform is a point of need analytical toolkit for safety ***,the sensitivity,specificity,and simplicity are still ***,we report a novel strategy(Au/δ-MnO_(2) hollow nanosphere and 3,3′,5,5′-tetramethylbenzidine(TMB)induced test strips for signal-on detection)that can be utilized for hexavalent chromium(Cr^(6+))***,Cr^(6+)(CrO_(4)^(2−)) as a smart switch can remarkably enhance the oxidase-like activity of Au/δ-MnO_(2) hollow *** presence of Cr^(6+) can regulate the surface electronic redistribution of Au/δ-MnO_(2) and adjust the geometric configuration,which leads to the improvement in oxidase-like activity of Au/δ-MnO_(2).As a proof-of-concept application,a visual paper-based sensing platform of Cr^(6+) along with quantitative analysis by the test strips was successfully *** paper-based sensing platform exhibits a linear range with excellent selectivity for other interfering substances and lower limit of detection of 0.09μmol·L^(−1),providing a promising toolkit at-home Cr^(6+) measurement and environmental monitoring.

关键词： Point of need Colorimetric biosensing platform Au/δ-MnO_(2) hollow nanosphere Test strip Cr^(6+)

Designing multi-heterogeneous interfaces of Ni-MoS_(2)@NiS_(2)@Ni_(3)S_(2)hybrid for hydrogen evolution

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Nano Research 2024年第6期17卷 4782-4789页

作者： Haoxuan Yu Junan Pan Yuxin Zhang Longlu Wang Huachao Ji Keyu Xu ting Zhi Zechao zhuang College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology) Nanjing University of Posts&Telecommunications(NJUPT)Nanjing 210023China Department of Chemical Engineering Columbia UniversityNew YorkNY 10027USA

The transition metal chalcogenides represented by MoS_(2)are the ideal choice for non-precious metal-based hydrogen evolution ***,whether in acidic or alkaline environments,the catalytic activity of pure MoS_(2)is still difficult to compete with *** studies have shown that the electronic structure of materials can be adjusted by constructing lattice-matched heterojunctions,thus optimizing the adsorption free energy of intermediates in the catalytic hydrogen production process of materials,so as to effectively improve the electrocatalytic hydrogen production activity of ***,it is still a great challenge to prepare heterojunctions with lattice-matched structures as efficient electrocatalytic hydrogen production ***,we developed a one-step hydrothermal method to construct Ni-MoS_(2)@NiS_(2)@Ni_(3)S_(2)(Ni-MoS_(2)on behalf of Ni doping MoS_(2))electrocatalyst with multiple heterogeneous interfaces which possesses rich catalytic reaction *** Ni-MoS_(2)@NiS_(2)@Ni_(3)S_(2)electrocatalyst produced an extremely low overpotential of 69.4 mV with 10 mA·cm^(−2)current density for hydrogen evolution reaction(HER)in 1.0 M *** work provides valuable enlightenment for exploring the mechanism of HER enhancement to optimize the surface electronic structure of MoS_(2),and provides an effective idea for constructing rare metal catalysts in HER and other fields.

关键词： MoS_(2) heterojunctions multiple heterogeneous interfaces hydrogen evolution