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A Localized Inter-Actuator Network Topology Repair Scheme for Wireless Sensor and Actuator Networks

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China Communications 2019年第2期16卷 215-232页

作者： yong feng Hai Liu Jie Yang Xiaodong Fu Yunnan Key Lab of Computer Technology Applications Kunming University of Science and Technology Nanjing Changjiang Electronics Group co. ltd

Node failure is one of the most severe problems that wireless sensor and actuator networks(WSANs) have to deal with. The failure of actuator nodes, in particular, may result in substantial consequences such as network partitioning, incorrect and incomplete decision execution for WSANs. This paper proposes an efficient localized scheme, called LANTR, to repair the damaged topology of inter-actuator network while single actuator node paralyzes. For the failure of an ordinary actuator node, LANTR can rapidly repair the topology through relocating only one-hop neighbors of the failure node, meanwhile, keep the original topology structure as much as possible. Given the magnitude of cut vertex actuators playing on the connectivity, LANTR designs a novel method for each cut vertex to select out a specific guardian node with the minimum degree or minimum cumulative degree from its neighbors, which can reduce the repair influence on the original topology and effectively reduce the coverage loss rate. The performance of the proposed scheme is evaluated and compared with several existing representative topology repair schemes, and the results indicate that LANTR can more effectively and efficiently repair the topology of inter-actuator networks.

关键词： wireless sensor and actuator networks inter-actuator networks topology repair coverage loss rate

Design of coordinator to eliminate redundant local retransmission in wireless networks

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 63-69页

作者： FANG Xi WANG Jun WANG yong JIANG feng Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China

Owing to limited bandwidth, high bit error rate, and bursty error in the wireless environment, the performance of the transmission control protocol （TCP） degrades greatly in wireless networks. Up to now, many researchers have contributed greatly to the wireless TCP field. However, in most of their works, the wireless TCP module usually works in the TCP layer and has no idea of the actual time of the packet transmission, which is determined by the Scheduler in the media access control （MAC） layer, and this will bring the inaccuracy to the local retransmission fimeout and induce the redundant local retransmission. In this article, a coordinator is introduced into the base-station （BS）, which can provide efficient cooperation between the TCP module and the scheduler module. On the bais of the performance analysis and simulation results, the proposed method is shown to eliminate redundant local retransmission, increase throughput, and improve TCP-level fairness in wireless networks. Moreover, this scheme is orthogonal to those existing wireless TCP schemes, thus it can give great compatibility to the current networks, and further enhance the performance of TCP under the condition that the performance improvement benefiting from the existing approaches will not be affected.

关键词： TCP wireless network coordinator scheduling throughput fairness

MicroRNA-409-5p Inhibits GIST Tumorigenesis and Improves Imatinib Resistance by Targeting KDM4D Expression

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Current Medical Science 2023年第5期43卷 935-946页

作者： Cheng QIU yong-dong feng Xi YANG GI Cancer Research Institute Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Objective Gastrointestinal stromal tumors(GISTs)can rapidly proliferate through *** studies indicated the potential influence of microRNA on the progression of tumor immature *** study aimed to explore the specific mechanism by which microRNA-409-5p(miR-409-5p)contributes to *** To identify genes potentially involved in the development and progression of GIST,the differences of miR-409-5p between tumors and adjacent tissues were first *** this analysis,target genes were *** further investigate the function of miRNA in GIST cells,two GIST cell lines(GIST-T1 and GIST882)were transfected with lentiviruses that stably expressed miR-409-5p and scrambled miRNA(negative control).Later,the cells were subjected to Western blotting and ELSA to determine any differences in angiogenesis-related *** In GISTs,there was a decrease in the expression levels of miR-409-5p compared to the adjacent *** was observed that the upregulation of miR-409-5p in GIST cell lines effectively inhibited the proteins hypoxia-inducible transcription factor 1β(HIF1β)and vascular endothelial growth factor A(VEGF-A).Further investigations revealed that miR-409-5p acted as an inhibitor of angiogenesis by binding to the 3′-UTR of Lysine-specific demethylase 4D(KDM4D)***,the combination of miR-409-5p with imatinib enhanced its inhibitory effect on *** This study demonstrated that the miRNA-409-5p/KDM4D/HIF1β/VEGF-A signaling pathway could serve as a novel target for the development of therapeutic strategies for the treatment of imatinib-resistance in GIST patients.

关键词： microRNA-409-5p KDM4D gastrointestinal stromal tumor

Security analysis of image encryption based on twodimensional chaotic maps and improved algorithm

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Frontiers of Electrical and Electronic Engineering in China 2009年第1期4卷 5-9页

作者： feng HUANG yong feng Department of Electrical and Information Engineering Hunan Institute of EngineeringXiangtan 411104China School of Electrical Engineering and Automation Harbin Institute of TechnologyHarbin 150001China

The article proposes a new algorithm to improve the security of image encryption based on twodimensional chaotic *** maps are often used in encrypting ***,the encryption has periodicity,no diffusion,and at the same time,the real keys space of encryption are fewer than the theoretical keys space,which consequently results in potential security ***,this article puts forward several ways to solve the problems including adding diffusion mechanism,changing the design of keys and developing a composite encryption *** designs an algorithm for the version B of the discretized baker map,which is one of the most prevalent chaotic maps,based on which a new image encryption is proposed to avoid the above *** simulation results show that the new encryption algorithm is valid and the result can be applied to other two-dimensional chaotic maps,such as the cat map.

关键词： chaotic map baker map image encryption

Rectifying control of wire diameter during dieless drawing by a deformation measuring method of interframe displacement

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International Journal of Minerals,Metallurgy and Materials 2012年第7期19卷 615-621页

作者： yong He Xue-feng Liu Fang Qin Jian-xin Xie Key Laboratory for Advanced Materials Processing (Ministry of Education) University of Science and Technology Beijing Beijing 100083 China

A deformation measurement method of interframe displacement was proposed in this paper. By online monitoring the shape di- mensions of both the deformation zone and its adjacent zone by machine vision, the initial and terminative positions of deformation were dynamically identified during dieless drawing, and the global monitoring and online closed-loop control of the deformation zone were achieved. The dieless drawing process was systematically carried out on NiTi shape memory alloy wires. It is shown that the deformation measurement method of interframe displacement can track the axial displacement of the wires, but this cannot be achieved by traditional machine vision. The initial and terminative positions of deformation can be accurately identified by this method. The proposed rectifying control technology can effectively decrease the wire diameter fluctuation during dieless drawing, that is, the standard deviation of the wire diameter fluctuation could be decreased fi＇om 0.30 to 0.08 mm after three passes of dieless drawing, indicating that the control system has a good rectifying ability.

关键词： wire drawing rectification deformation machine vision closed loop control systems nickel alloys sha^oe memory effect

Discovering admissible Web services with uncertain QoS

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Frontiers of Computer Science 2015年第2期9卷 265-279页

作者： Xiaodong FU Kun YUE Li LIU Ping ZOU yong feng Yunnan Provincial Key Laboratory of Computer Technology Application Faculty of Information Engineering and Automation Kunming University of Science and Technology Kunming 650500 China School of Information Science and Engineering Yunnan University Kunming 650091 China Faculty of Management and Economics Kunming University of Science and Technology Kunming 650093 China

Open and dynamic environments lead to inher- ent uncertainty of Web service QoS （Quality of Service）, and the QoS-aware service selection problem can be looked upon as a decision problem under uncertainty. We use an empiri- cal distribution function to describe the uncertainty of scores obtained from historical transactions. We then propose an approach to discovering the admissible set of services in- cluding alternative services that are not dominated by any other alternatives according to the expected utility criterion. Stochastic dominance （SD） rules are used to compare two services with uncertain scores regardless of the distribution form of their uncertain scores. By using the properties of SD rules, an algorithm is developed to reduce the number of SD tests, by which the admissible services can be reported pro- gressively. We prove that the proposed algorithm can be run on partitioned or incremental alternative services. Moreover, we achieve some useful theoretical conclusions for correct pruning of unnecessary calculations and comparisons in each SD test, by which the efficiency of the SD tests can be im- proved. We make a comprehensive experimental study using real datasets to evaluate the effectiveness, efficiency, and scal- ability of the proposed algorithm.

关键词： Web services uncertain QoS partial preference,empirical distribution function stochastic dominance admis-sible set

Redshift Dependence of the Low-energy Spectral Index of Gamma-Ray Bursts Revisited

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Research in Astronomy and Astrophysics 2023年第12期23卷 57-62页

作者： Xiao-Li Zhang yong-feng Huang Ze-Cheng Zou Department of Physics Nanjing UniversityNanjing 210023China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210023China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China

A negative correlation was found to exist between the low-energy spectral index and the redshift of gamma-ray bursts(GRBs)by Amati et *** was later confirmed by Geng&Huang and Gruber et al.,but the correlation was also found to be quite dispersive when the sample size was significantly *** this study,we have established two even larger samples of GRBs to further examine the *** of our samples consists of316 GRBs detected by the Swift satellite,and the other one consists of 80 GRBs detected by the Fermi *** is found that there is no correlation between the two parameters for the Swift sample,but there does exist a weak negative correlation for the Fermi *** correlation becomes even more significant when the spectral index at the peak flux is *** is argued that the absence of the correlation in the Swift sample may be due to the fact that Swift has a very narrow energy response so that it could not measure the low-energy spectral index accurately *** studies based on even larger GRB samples are solicited.

关键词： (stars:)gamma-ray burst general-methods statistical-catalogs

Solution of Magnetohydrodynamic Oscillations in Electrolytes with Ion-Neutral Collisions

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Chinese Physics Letters 2012年第11期29卷 157-161页

作者： LIU Yuan-Tao ZHAO Hua LI Lei feng yong-yong Center for Space Science and Applied Research Chinese Academy of SciencesBeijing 100190 Graduate University of Chinese Academy of Sciences Beijing 100049

The single-fluid Magnetohydrodynamic(MHD)equations for electrolytes in the presence of a magnetic field are derived from multi-fluid MHD equations with ion-neutral collisions in partially ionized conductive *** dispersion relationship of MHD waves is also investigated,which is different from that for plasmas or liquid *** on the equations,we find that MHD waves are dispersive in electrolytes,and the critical frequencies for excitation of Alfven waves vary with magnetic field or conductivity,so the exciting of MHD waves is severely restricted in electrolytes with relatively low conductivity except at an extremely low frequency or when it is permeated by a considerably strong ambient magnetic *** theories are applied to seawater to estimate the magnetic field vibration caused by the large-scale motion of seawater(e.g.,ocean currents or tides).It is found that high frequency waves are dampened severely in seawater,while low frequency waves can propagate over a long distance without much attenuation.

关键词： tides seawater conductivity

Multi-objective optimization and evaluation of supercritical CO_(2) Brayton cycle for nuclear power generation

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Nuclear Science and Techniques 2024年第2期35卷 183-209页

作者： Guo-Peng Yu yong-feng Cheng Na Zhang Ping-Jian Ming Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China School of Civil Engineering and Architecture East China Jiaotong UniversityNanchang 330013China

The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle *** models of four Brayton cycle layouts are developed in this study for different reactors to reduce the cost and increase the thermohydraulic performance of nuclear power generation to promote the commercialization of nuclear *** analysis,multi-objective optimizations,and four decision-making methods are applied to obtain each Brayton scheme’s optimal thermohydraulic and economic *** show that for the same design thermal power scale of reactors,the higher the core’s exit temperature,the better the Brayton cycle’s thermo-economic *** the four-cycle layouts,the recompression cycle(RC)has the best overall performance,followed by the simple recuperation cycle(SR)and the intercooling cycle(IC),and the worst is the reheating cycle(RH).However,RH has the lowest total cost of investment(C_(tot))of$1619.85 million,and IC has the lowest levelized cost of energy(LCOE)of 0.012$/(kWh).The nuclear Brayton cycle system’s overall performance has been improved due to *** performance of the molten salt reactor combined with the intercooling cycle(MSR-IC)scheme has the greatest improvement,with the net output power(W_(net)),thermal efficiencyη_(t),and exergy efficiency(η_(e))improved by 8.58%,8.58%,and 11.21%,*** performance of the lead-cooled fast reactor combined with the simple recuperation cycle scheme was optimized to increase C_(tot) by 27.78%.In comparison,the internal rate of return(IRR)increased by only 7.8%,which is not friendly to investors with limited *** the nuclear Brayton cycle,the molten salt reactor combined with the recompression cycle scheme should receive priority,and the gas-cooled fast reactor combined with the reheating cycle scheme should be considered carefully.

关键词： Supercritical CO_(2)Brayton cycle Nuclear power generation Thermo-economic analysis Multi-objective optimization Decision-making methods