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Is playing-as-downloading feasible in an eMule P2P file sharing system?

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第6期11卷 465-475页

作者： Wen-yi WANG yao-wu chen Advanced Digital Technology and lnstruments Institute Zhejiang University Hangzhou 310027 China

Peer-to-peer(P2P) swarm technologies have been shown to be very efficient for large scale content distribution systems, such as the well-known BitTorrent and eMule ***, these systems have been designed for generic file sharing with little consideration of media streaming support, and the user cannot start a movie playback before it is completely *** playing-as-downloading capability would be particularly useful for a downloading peer to evaluate if a movie is valuable to be downloaded, and it could also help the P2P content distribution system to locate and eliminate the polluted *** this paper we address this issue by introducing a new algorithm, wish driven chunk distribution(WDCD), which enables the P2P file sharing system to support the video-on-demand(VOD) function while keeping the P2P native downloading speed.A new parameter named next-play-frequency is added to the content chunk to strike a replication balance between downloading and streaming *** modify the eMule as the test bed by adding the WDCD algorithm and then verify the prototype implementation by *** experimental results show that the proposed algorithm can keep the high downloading throughput performance of the eMule system with a good playing-as-downloading function.

关键词： Peer-to-peer(P2P) Video-on-demand(VOD) Playing-as-downloading eMule

Optimized simulated annealing algorithm for thinning and weighting large planar arrays

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第4期11卷 261-269页

作者： Peng chen Bin-jian SHEN Li-sheng ZHOU yao-wu chen Institute of Advanced Digital Technologies and lnstrumentation Zhejiang University Hangzhou 310027 China Hangzhou Applied Acoustics Research Institute Hangzhou 310012 China

This paper proposes an optimized simulated annealing(SA) algorithm for thinning and weighting large planar arrays in 3D underwater sonar imaging *** optimized algorithm has been developed for use in designing a 2D planar array(a rectangular grid with a circular boundary) with a fixed side-lobe peak and a fixed current taper ratio under a narrow-band *** extensions of the SA algorithm and the procedure for the optimized SA algorithm are *** examples of planar arrays are used to assess the efficiency of the optimized *** proposed method achieves a similar beam pattern performance with fewer active transducers and faster convergence ability than previous SA algorithms.

关键词： Simulated annealing(SA) Sparse planar arrays 3D underwater sonar imaging Beam pattern Optimization

A network-aware error-resilient method using prioritized intra refresh for wireless video communications

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第8期10卷 1169-1176页

作者： Han-jie MA Fan ZHOU Rong-xin JIANG yao-wu chen Institute of Advanced Digital Technology and Instrumentation Zhejiang University Hangzhou 310027 China

We propose a novel prioritized intra refresh method for the wireless video *** proposed method considers the characteristics of the human visual system,the error-sensitivity of the bitstream,and the state of the time-varying wireless channel *** expected perceptual distortion model was used to adjust the intra refresh rate *** model consists of the perceptual weight map based on an attention model,the bit error probability map based on bitstream size,and the dynamic channel state information(CSI).Experimental results indicate that,compared with other intra refresh methods that consider only the content of the video or the CSI,the proposed method improves the average peak signal-to-noise ratio(PSNR) of the whole frame by about 0.5 dB,and improves the average PSNR of the attention-area by about 0.8 dB.

关键词： Intra refresh. Distortion. Perceotual weieht. Error-sensitivity. Channel state information (CSI)

Smart Behavior of Carbon Fiber Reinforced Cement-based Composite

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Journal of Materials Science & Technology 2003年第3期19卷 239-242页

作者： wu yao, Bing chen Keru wuState Key Laboratory of Concrete Materials Research, Tongji University, Shanghai 200092, China Lab. of Concrete Mat. Res. Tongji Univ. Shanghai 200092 China

The electrical characteristics of cement-based material can be remarkably improved by the addition of short carbon fibers. Carbon fiber reinforced cement composite (CFRC) is an intrinsically smart material that can sense not only the stress and strain, but also the temperature. In this paper, variations of electrical resistivity with external applied load, and relation of thermoelectric force and temperature were investigated. Test results indicated that the electrical signal is related to the increase in the material volume resistivity during crack generation or propagation and the decrease in the resistivity during crack closure. Moreover, it was found that the fiber addition increased the linearity and reversibility of the Seebeck effect in the cement-based materials. The change of electrical characteristics reflects large amount of information of inner damage and temperature differential of composite, which can be used for stress-strain or thermal self-monitoring by embedding it in the concrete structures.

关键词： Carbon fiber Cement-based composite Smart material Seebeck effect

Early lactate clearance as a reliable predictor of initial poor graft function after orthotopic liver transplantation

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Hepatobiliary & Pancreatic Diseases International 2011年第6期10卷 587-592页

作者： Jian-Feng wu,Rong-yao wu,Juan chen,Bin Ou-Yang,Min-Ying chen and Xiang-Dong Guan Department of Surgical Intensive Care Unit,First Affiliated Hospital,Sun Yat-Sen University,Guangzhou 510080,China Department of Surgical Intensive Care Unit First Affliated Hospital Sun Yat-Sen University Guangzhou 510080 China

BACKGROUND:Initial poor graft function (IPGF) following orthotopic liver transplantation is a major determinant of postoperative survival and *** clearance is a good marker of liver *** this study,we investigated the clinical utility of early lactate clearance as an early and accurate predictor for IPGF following liver ***:This was a prospective observational study of 222 patients referred to the surgical intensive care unit (SICU) after orthotopic liver *** IPGF group consisted of patients with alanine aminotransferase (ALT) and/or aspartate aminotransferase (AST) >1500 IU/L within 72 hours after orthotopic liver *** lactate clearance was defined as lactate at SICU presentation (hour 0) minus lactate at hour 6,divided by lactate at SICU *** model for end-stage liver disease (MELD) score,Child-Pugh score and laboratory data including AST,ALT,total bilirubin (TB) and prothrombin time (PT) were recorded at SICU presentation and compared between the non-IPGF and IPGF groups Receiver operating characteristic (ROC) curves were plotted to measure the performance of early lactate clearance,MELD score,Child-Pugh score,TB and ***:IPGF occurred in 45 of the 222 patients (20.3%).The early lactate clearance in the non-IPGF group was markedly higher than that in the IPGF group (43.2±13.8% vs 13.4±13.7% P<0.001).The optimum cut-off value for early lactate clearance predicting IPGF was 24.8% (sensitivity 95.5%,specificity 88.9%).The area under the curve of the ROC was 0.961,which was significantly superior to MELD score,Child-Pugh score TB and *** with early lactate clearance ≤24.8% had a higher IPGF rate (OR=169) and a higher risk of in-hospital mortality (OR=3.625).CONCLUSIONS:Early lactate clearance can serve as a prompt and accurate bedside predictor of *** with early lactate clearance less than 24.8% are associated with a higher incidence of IPGF.

关键词： early lactate clearance initial poor graft function liver transplantation

硼、钠复合掺杂对贝利特-硫铝酸钙水泥性能及微观结构的影响

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材料导报 2017年第5期31卷 128-133页

作者：吴梦雪姚武李晨凌桥同济大学先进土木工程材料教育部重点实验室上海201804

采用粘土、铝矾土、碳酸钙为主要原料制备以贝利特(C_2S)、硫铝酸钙和铁铝酸钙为主导矿物的低碳排放水泥熟料(BCSAF),并通过硼(B)和钠(Na)复合掺杂对C_2S矿物进行活化。将熟料与无水石膏按比例混合后制备水泥,研究复合掺杂对水泥净浆强... 详细信息

采用粘土、铝矾土、碳酸钙为主要原料制备以贝利特(C_2S)、硫铝酸钙和铁铝酸钙为主导矿物的低碳排放水泥熟料(BCSAF),并通过硼(B)和钠(Na)复合掺杂对C_2S矿物进行活化。将熟料与无水石膏按比例混合后制备水泥,研究复合掺杂对水泥净浆强度及微观结构的影响。采用X射线衍射全谱拟合定量相分析法、红外光谱、扫描电子显微镜、X射线能谱分析等测试方法表征熟料及水泥水化浆体组成与结构。研究结果表明,一定掺量的B和Na复合掺杂制备BCSAF水泥熟料可在常温下稳定α′-C_2S或更高活性的C_2S,减少熟料中β-C_2S含量,从而实现C_2S矿物的活化,提高BCSAF水泥熟料早期水化活性,显著提高水泥浆体抗压强度。

关键词：贝利特硫铝酸钙复合掺杂硼钠

Highly conductive and stable iodine doped argyrodite electrolyte for all-solid-state lithium batteries

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Journal of Energy Chemistry 2025年第1期100卷 50-58页

作者： Gaozhan Liu Jing Zhang Jing Yang Jinghui chen Xingyue Xiao Xiayin yao Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences

Lithium argyrodites with high ionic conductivity and low cost are considered as one of the most prospective solid electrolytes for all-solid-state lithium ***,the poor chemical stability and compatibility with lithium metal limit their ***,Li5.4PS4.4Cl1.4I0.2solid electrolyte with high ionic conductivity of 11.49 m S cm-1and improved chemical stability is synthesized by iodine *** ultra-thin Li5.4PS4.4Cl1.4I0.2membrane with thickness of 10μm can be obtained by wet coating process,exhibiting a high ionic conductivity of 2.09 mS cm-1and low areal resistance of 1.17Ω***,iodine doping could in-situ form LiI at the lithium/electrolyte interface and improve the critical current density of Li5.4PS4.4Cl1.6from 0.8 to 1.35 mA *** resultant LiCoO2/Li5.4PS4.4Cl1.4I0.2/Li battery shows excellent cycling stability at 1 C,with a reversible specific capacity of 110.1 mA h g-1and a retention of 80.5% after 1000 *** addition,the assembled LiCoO2/Li5.4PS4.4Cl1.4I0.2membrane/Li pouch cell delivers an initial discharge capacity of 110.4 mA h g-1and 80.5% capacity retention after 100 cycles.

关键词： Argyrodite electrolytes Iodine doping Ionic conductivity Stability All-solid-state lithium battery

Ammonia pyrolysis oxidation excited by nanosecond pulsed discharge:Global/fluid models hybrid solution

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Journal of Energy Chemistry 2025年第1期100卷 385-396页

作者： Mingming Zhang Hanyu wu Qi chen Jiaxin Yang Bonan Liu School of Mechanical Electronic and Control Engineering Beijing Jiaotong University China University of Petroleum

The kinetic characteristics of plasma-assisted oxidative pyrolysis of ammonia are studied by using the global/fluid models hybrid solution ***,the stable products of plasma-assisted oxidative pyrolysis of ammonia are *** results show that the consumption of NH3/O2and the production of N2/H2change linearly with the increase of voltage,which indicates the decoupling of nonequilibrium molecular excitation and oxidative pyrolysis of ammonia at low ***,the detailed reaction kinetics mechanism of ammonia oxidative pyrolysis stimulated by a nanosecond pulse voltage at low pressure and room temperature is *** on the reaction path analysis,the simplified mechanism is *** detailed and simplified mechanism simulation results are compared with experimental data to verify the accuracy of the simplified ***,based on the simplified mechanism,the fluid model of ammonia oxidative pyrolysis stimulated by the nanosecond pulse plasma is established to study the pre-sheath/sheath behavior and the resultant consumption and formation of key *** results show that the generation,development,and propagation of the pre-sheath have a great influence on the formation and consumption of *** consumption of NH3by the cathode pre-sheath is greater than that by the anode pre-sheath,but the opposite is true for OH and O（1S）.However,within the sheath,almost all reactions do not ***,by changing the parameters of nanosecond pulse power supply voltage,it is found that the electron number density,electron current density,and applied peak voltages are not the direct reasons for the structural changes of the sheath and ***,the discharge interval has little effect on the sheath structure and gas mixture *** research results of this paper not only help to understand the kinetic promotion of non-equilibrium excitation in the process of oxidative pyrolysis but also help to explore th

关键词： Nanosecond pulsed discharge Ammonia Oxidative pyrolysis Fluid model Global model

Glycolytic dysregulation in Alzheimer's disease:unveiling new avenues for understanding pathogenesis and improving therapy

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Neural Regeneration Research 2025年第8期20卷 2264-2278页

作者： You wu Lijie Yang Wanrong Jiang Xinyuan Zhang Zhaohui yao Department of Geriatrics Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

Alzheimer's disease poses a significant global health challenge owing to the progressive cognitive decline of patients and absence of curative *** current therapeutic strategies,primarily based on cholinesterase inhibitors and N-methyl-Daspartate receptor antagonists,offer limited symptomatic relief without halting disease progression,highlighting an urgent need for novel research directions that address the key mechanisms underlying Alzheimer's *** studies have provided insights into the critical role of glycolysis,a fundamental energy metabolism pathway in the brain,in the pathogenesis of Alzheimer's *** in glycolytic processes within neurons and glial cells,including microglia,astrocytes,and oligodendrocytes,have been identified as significant contributors to the pathological landscape of Alzheimer's *** changes impact neuronal health and function,thus offering promising targets for therapeutic *** purpose of this review is to consolidate current knowledge on the modifications in glycolysis associated with Alzheimer's disease and explore the mechanisms by which these abnormalities contribute to disease onset and *** focus on the pathways through which glycolytic dysfunction influences Alzheimer's disease pathology should provide insights into potential therapeutic targets and strategies that pave the way for groundbreaking treatments,emphasizing the importance of understanding metabolic processes in the quest for clarification and management of Alzheimer's disease.

关键词： Alzheimer’s disease glial cells glycolysis neuronal metabolism pathogenesis therapeutic targets