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Acta Mathematicae Applicatae Sinica 2022年第3期38卷 601-613页

作者： Da-kang CEN zhi-bo wang Yan MO School of Mathematics and Statistics Guangdong University of TechnologyGuangzhou 510006China

In this paper,a compact finite difference scheme for the nonlinear fractional integro-differential equation with weak singularity at the initial time is developed,with O(N^(-(2-α))+M^(-4))accuracy order,where N;M denote the numbers of grids in temporal and spatial direction,α ∈(0,1)is the fractional *** recover the full accuracy based on the regularity requirement of the solution,we adopt the L1 method and the trapezoidal product integration(PI)rule with graded meshes to discretize the Caputo derivative and the Riemann-Liouville integral,respectively,further handle the nonlinear term carefully by the Newton linearized *** on the discrete fractional Gr¨onwall inequality and preserved discrete coefficients of Riemann-Liouville fractional integral,the stability and convergence of the proposed scheme are analyzed by the energy *** results are also confirmed by a numerical example.

关键词： nonlinear fractional integro-differential equation graded meshes discrete fractional Gr?nwall inequality compact difference scheme stability and convergence

Adaptive modulation for SVD-based MIMO systems with outdated CSI

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The Journal of China Universities of Posts and Telecommunications 2009年第4期16卷 78-83页

作者： YAN zhi wang Wen-bo wang Xiao-ting ZHENG Kan Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

The performance of singular value decomposition （SVD）-based multiple-input multiple-output （MIMO） with adaptive modulation （AM） is dependent on the accuracy of the channel state information （CSI） at the transmitter and the receiver. However, for a time-varying channel, the CSI obtained at the transmitter or the receiver is incorrect owing to an inherent delay or error. A typical system employing SVD suffers degradation in capacity when outdated CSI is used to transmit data. This article first addresses the adaptive modulation MIMO system designed under perfect CSI assumption. Based on that, two scenarios of outdated CSI are investigated and analyzed. The effect of imperfect CSI on the system performance is focused on and a simple post processing SNR （pSNR） adjustment design is proposed on AM system in the two scenarios for reducing degradation in average spectral efficiency （ASE）. Simulation results show that these designs provide good performance in an adaptive way, and enable the adaptive MIMO system considerably more to be robust against CSI imperfection.

关键词： MIMO SVD adaptive modulation ohtdated CSI

Joint linear precoder and power allocation design for uplink MIMO systems with limited feedback

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The Journal of China Universities of Posts and Telecommunications 2009年第3期16卷 14-18页

作者： YAN zhi wang Wen-bo wang Jian-feng ZHENG Kan Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

In this article, the authors consider joint design of a linear precoder and power allocation for uplink multiuser multiple input multiple output （MIMO） communication systems with limited feedback to improve the bit error rate （BER） performance for all users. Precoder selection from the codebook set is directly based on the exact BER performance, instead of other suboptimal criteria, to achieve the optimal precoder matrix, but closed-form expressions may not exist in the view of power allocation based directly on the BER criterion. From this perspective, the authors propose the joint transmitter optimization algorithm for the consideration of precoder design, with total power constraint for asymptotic MBER （AMBER） criterion. In this AMBER criterion, a closed-form solution has been derived for power allocation with an optimal precoder. The simulation results show that the proposed joint design algorithm can achieve a much better performance than precoding with uniform power allocation and only consideration of power allocation.

关键词： MIMO linear precoder power allocation spatial multiplexing multiuser

HierTrack:an energy-efficient cluster-based target tracking system for wireless sensor networks

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第6期14卷 395-406页

作者： zhi-bo wang zhi wang Hong-long CHEN Jian-feng LI Hong-bin LI Jie SHEN Department of Control Science and Engineering Zhejiang University College of Information and Control Engineering China University of Petroleum

Target tracking is a typical and important application of wireless sensor networks(WSNs).Existing target tracking protocols focus mainly on energy efficiency,and little effort has been put into network management and real-time data routing,which are also very important issues for target *** this paper,we propose a scalable cluster-based target tracking framework,namely the hierarchical prediction strategy(HPS),for energyefficient and real-time target tracking in large-scale *** organizes sensor nodes into clusters by using suitable clustering protocols which are beneficial for network management and data *** a target moves in the network,cluster heads predict the target trajectory using Kalman filter and selectively activate the next round of sensors in advance to keep on tracking the *** estimated locations of the target are routed to the base station via the backbone composed of the cluster heads.A soft handoff algorithm is proposed in HPS to guarantee smooth tracking of the target when the target moves from one cluster to *** the framework of HPS,we design and implement an energy-efficient target tracking system,HierTrack,which consists of 36 sensor motes,a sink node,and a base *** simulation and experimental results show the efficiency of our system.

关键词： Wireless sensor networks Cluster Energy efficiency Target tracking Scalability Real-time data routing

Characterization of the Purified Glutathione S-transferases from Two Psocids Liposcelis bostrychophila and ***

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Agricultural Sciences in China 2010年第7期9卷 1008-1016页

作者： DOU Wei XIAO Li-sha NIU Jin-zhi JIANG Hong-bo wang Jin-jun Key Laboratory of Entomology and Pest Control Engineering College of Plant Protection Southwest University Chongqing 400716 P.R. China

Glutathione S-transferases（GSTs） from Liposcelis bostrychophila Badonnel and ***（Enderlein）（Psocoptera：Liposcelididae） were purified by glutathione-agarose affinity chromatography,and characterized subsequently by their Michaelis-Menten kinetics toward the artificial substrates 1-chloro-2,4-dinitrobenzene（CDNB） and reduced glutathione（GSH）,*** specific activity of the purified GST toward CDNB was 2.3-fold higher in *** than in *** the specific activities of purified enzymes varied between the two species,the purification yields were ***-PAGE revealed one band at 23 kDa for both the *** of *** exhibited higher Michaelis-Menten constants（Km） but lower maximal velocity（Vmax） values than those of *** optimum pH for CDNB conjugation of *** and *** GSTs was 7.0 and 7.5,and optimum temperature was 35 and 40°C,*** kinetics showed that cibacron blue,curcumin,bromosulfalein,ethacrynic acid,and carbosulfan had excellent inhibitory effects on GSTs in both species,but the inhibitory effects of beta-cypermethrin,fenpropathrin,tetraethylthiuram disulfide,and diethyl maleate were not significant.

关键词： GSTs purification psocids xenobiotic compounds

Baicalin,silver titanate,Bletilla striata polysaccharide and carboxymethyl chitosan in a porous sponge dressing for burn wound healing

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Journal of Integrative Medicine 2023年第5期21卷 487-495页

作者： Yan-rong Gong Cheng Zhang Xing Xiang zhi-bo wang Yu-qing wang Yong-hua Su Hui-qing Zhang School of Traditional Chinese Medicine Naval Medical UniversityShanghai 200433China Department of Dermatology Shuguang HospitalShanghai University of Traditional Chinese MedicineShanghai 201203China Department of Dermatology Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghai 200437China Institute of Dermatology Shanghai Academy of Traditional Chinese MedicineShanghai 201203China

Objective This study tests the efficacy of Bletilla striata polysaccharide(BSP),carboxymethyl chitosan(CMC),baicalin(BA)and silver titanate(ST)in a wound dressings to fight infection,promote healing and provide superior *** The antibacterial activity of BA and ST was evaluated in vitro using the inhibition zone ***/ST/BSP/CMC porous sponge dressings were prepared and *** biocompatibility of BA/ST/BSP/CMC was assessed using the cell counting kit-8 *** therapeutic effect of BA/ST/BSP/CMC was further investigated using the dorsal skin burn model in Sprague-Dawley *** The wound dressing had good antibacterial activity against Escherichia coli and Staphylococcus aureus through BA and ST,while the combination of BSP and CMC played an important role in promoting wound *** BA/ST/BSP/CMC porous sponge dressings were prepared using a freeze-drying method with the concentrations of BA and ST at 20 and 0.83 mg/mL,respectively,and the optimal ratio of 5%BSP to 4%CMC was 1:*** average porosity,water absorption and air permeability of BA/ST/BSP/CMC porous sponge dressings were measured to be 90.43%,746.1%and 66.60%,*** treatment for 3 and 7 days,the healing rates of the BA/ST/BSP/CMC group and BA/BSP/CMC group were significantly higher than those of the normal saline(NS)group and silver sulfadiazine(SSD)group(P<0.05).Interleukin-1βexpression in the BA/ST/BSP/CMC group at 1 and 3 days was significantly lower than that in the other three groups(P<0.05).After being treated for 3 days,vascular endothelial growth factor expression in the BA/BSP/CMC group and BA/ST/BSP/CMC group was significantly higher than that in the NS group and SSD group(P<0.05).Inspection of histological sections showed that the BA/ST/BSP/CMC group and BA/BSP/CMC group began to develop scabbing and peeling of damaged skin after 3 days of treatment,indicating accelerated healing relative to the NS group and SSD *** The opt

关键词： Wound dressing Baicalin Bletilla striata polysaccharide Silver titanate Carboxymethylchitosan

End-to-end delay analysis for networked systems

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Frontiers of Information Technology & Electronic Engineering 2015年第9期16卷 732-743页

作者： Jie SHEN Wen-bo HE Xue LIU zhi-bo wang zhi wang Jian-guo YAO Department of Control Science and Engineering Zhejiang University School of Computer Science Mc Gill University School of Computer Wuhan University Su zhou Institute of Wuhan University School of Software Shanghai Jiao Tong University

End-to-end delay measurement has been an essential element in the deployment of real-time services in networked systems. Traditional methods of delay measurement based on time domain analysis, however, are not efficient as the network scale and the complexity increase. We propose a novel theoretical framework to analyze the end-to-end delay distributions of networked systems from the frequency domain. We use a signal flow graph to model the delay distribution of a networked system and prove that the end-to-end delay distribution is indeed the inverse Laplace transform of the transfer function of the signal flow graph. ~vo efficient methods, Cramer＇s rule-based method and the Mason gain rule-based method, are adopted to obtain the transfer function. By analyzing the time responses of the transfer function, we obtain the end-to-end delay distribution. Based on our framework, we propose an efficient method using the dominant poles of the transfer function to work out the bottleneck links of the network. Moreover, we use the framework to study the network protocol performance. Theoretical analysis and extensive evaluations show the effectiveness of the proposed approach.

关键词： Networked system End-to-end Delay distribution

Exact Location of Linear B-cell Epitopes of VP3 Protein of Goose Parvovirus

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畜牧兽医学报 2011年第B12期42卷 34-39页

作者： GUO Lu JU Huan-yu YU Tian-fei JING zhi-qiang MA bo wang Jun-wei （College of Veterinary Medicine Northeast Agricultural University Harbin 150030 China）

Four monoclonal antibodies (MAbs) against Goose Parvovirus (GPV) VP3 protein already available were used to precisely locate linear B-cell epitopes in VP3 of GPV. The epitopes, recognized by four MAbs, had already been identified at low levels of resolution. Complementary oligonucleotides encoding ten amino acid fragments, with five amino acid overlaps were designed with suitable sticky ends for recombination with pET-32a and subsequent expression as small-fragment fusion proteins. Antigenicity of specific oligopeptides was determined by Western blotting with the MAbs. Using the same methods, amino acids were deleted one by one from the peptides of interest, enabling the two epitopes to be precisely located at amino acids 430-435 (-DRIMNP-) and 643-647 (-VFIKN-).

关键词： VP3基因鹅细小病毒 B细胞表位 VP3蛋白抗原表位线性单克隆抗体位置

Spatial heterogeneity of fine root biomass of Pinus massoniana forests in the Three Gorges Reservoir Area, China

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Forestry Studies in China 2013年第1期15卷 13-23页

作者： Rui-Li wang Rui-Mei CHENG Wen-Fa XIAO Xiao-Hui FENG Ze-Bin LIU Xiao-Rong wang zhi-bo wang Key Laboratory of Forest Ecology and Environment of State Forestry Administration Research Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry Center for Agricultural Resources Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences Hubei Forestry Academy Research Institute of Forest Resource Information Techniques Chinese Academy of Forestry

Environmental heterogeneity is a constant presence in the natural world that significantly affects plant behavior at a variety of levels of complexity. In order to estimate the spatial pattern of fine root biomass in the Three Gorges Reservoir Area, the spatial heterogeneity of fine root biomass in the upper layer of soils （0-10 cm） in three Mas- son pine （Pinus massoniana） stands in the Three Gorges Reservoir Area, China, was studied in 30 m x 30 m plots with geostatistical analysis. The results indicate that 1） both the live and dead fine root biomass of stand 2 were less than those of other stands, 2） the spatial variation of fine roots in the three stands was caused together by structural and ran- dom factors with moderate spatial dependence and 3） the magnitude of spatial heterogeneity of live fine roots ranked as： stand 3 〉 stand 1 〉 stand 2, while that of dead fine roots was similar in the three stands. These findings suggested that the range of spatial autocorrelation for fine root biomass varied considerably in the Three Gorges Reservoir Area, while soil properties, such as soil bulk density, organic matter and total nitrogen, may exhibit great effect on the spatial distribution of fine roots. Finally, we express our hope to be able to carry out further research on the quantitative relation- ship between the spatial heterogeneous patterns of plant and soil properties.

关键词： spatial heterogeneity geostatistics Pinus massoniana fine root biomass Three Gorges Reservoir Area

Impact of Startup Strategy and Buffer Tank Volume on the Compressor Inlet State for a 3-MW sCO2 Brayton Cycle

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Journal of Thermal Science 2025年第1期34卷 159-175页

作者： ZHAO Decai wang bo Key Laboratory of Advanced Energy and Power Institute of Engineering Thermophysics(IET)Chinese Academy of Sciences (CAS) University of Chinese Academy of Sciences

The supercritical carbon dioxide（sCO2） Brayton cycle system has become an emerging and highly promising method of thermal power conversion due to its efficiency advantage,system compactness,and excellent adaptability of the heat *** the low carbon sCO2Brayton cycle testbed with cycle output power approaching 3 MW,a relatively detailed dynamic simulation model of the entire system is constructed to explore the dynamic response characteristics of the system with different startup strategies and different buffer tank volumes during the startup *** simulation results indicate that the smaller the volume of the buffer tank,the more rapid and obvious the parameter fluctuation in the buffer tank during the *** the allowable relative deviation limit of density is 5%,then the ratio of the buffer tank volume to the volume of the entire closed loop should not be lower than 36.80%.The strategy of simultaneous temperature and speed increase during turbine bypass start can effectively reduce the fluctuation of compressor inlet parameters and reach the steady-state more *** paper provides the recommended matching table for the opening of the turbine bypass valve（TBV） and the main regulating valve（MGV） to reduce the parameter fluctuation during the bypass *** effectiveness of the proposed turbine bypass and bypass switching startup strategy is verified by simulation,which may be used as a reference for test bench's future debugging and operation.

关键词： buffer tank dynamic characteristic dynamic model sCO2 Brayton cycle startup strategy