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Current advances of biocontainment strategy in synthetic biology

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Chinese Journal of Chemical Engineering 2023年第4期56卷 141-151页

作者： Xueying Zhu zhaoyang zhang Bin Jia Yingjin Yuan Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(Ministry of Education) School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Synthetic biotechnology has led to the widespread application of genetically modified organisms(GMOs)in biochemistry, bioenergy, and therapy. However, the uncontrolled spread of GMOs may lead to genetic contamination by horizontal gene transfer, resulting in unpredictable biosafety risks. To deal with these challenges, many effective methods have been developed for biocontainment. In this article, we summarize and discuss recent advances in biocontainment strategies from three aspects: DNA replication, transcriptional regulation, and protein translation. We also briefly introduce the efforts in the biocontainment convention, such as the recent publication of the Tianjin Biosecurity Guidelines for the Code of Conduct for Scientists.

关键词： Genetically modified organisms(GMOs) Biocontainment Biosecurity Synthetic biology Molecular biology Biotechnology

Energy-efficient spectrum-aware clustering for cognitive radio sensor networks

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Chinese Science Bulletin 2012年第28期57卷 3731-3739页

作者： zhang HuaZi zhang zhaoyang YUEN Chau Department of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 310027China Zhejiang Provincial Key Laboratory of Information Network Technology Hangzhou 310027China Singapore University of Technology and Design Singapore

As a smart combination of cognitive radio networks and wireless sensor networks,recently introduced cognitive radio sensor network(CRSN) poses new challenges to the design of topology maintenance techniques for dynamic primary-user *** paper aims to provide a solution to the energy-efficient spectrum-aware CRSN clustering ***,we design the clustered structure,establish a network-wide energy consumption model and determine the optimal number of *** then employ the ideas from constrained clustering and propose both a centralized spectrum-aware clustering algorithm and a distributed spectrum-aware clustering(DSAC) *** extensive simulations,we demonstrate that DSAC can effectively form clusters under a dynamic spectrum-aware ***,DSAC exhibits preferable scalability and stability with its low complexity and quick convergence under dynamic spectrum variation.

关键词：无线传感器网络认知无线电频谱感知集群节能高效聚类问题无线电网络

Information-Theoretic Limits on Compression of Semantic Information

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China Communications 2024年第7期21卷 1-16页

作者： Tang Jiancheng Yang Qianqian zhang zhaoyang College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 310007China

As conventional communication systems based on classic information theory have closely approached Shannon capacity,semantic communication is emerging as a key enabling technology for the further improvement of communication ***,it is still unsettled on how to represent semantic information and characterise the theoretical limits of semantic-oriented compression and *** this paper,we consider a semantic source which is characterised by a set of correlated random variables whose joint probabilistic distribution can be described by a Bayesian *** give the information-theoretic limit on the lossless compression of the semantic source and introduce a low complexity encoding method by exploiting the conditional *** further characterise the limits on lossy compression of the semantic source and the upper and lower bounds of the rate-distortion *** also investigate the lossy compression of the semantic source with two-sided information at the encoder and decoder,and obtain the corresponding rate distortion *** prove that the optimal code of the semantic source is the combination of the optimal codes of each conditional independent set given the side information.

关键词： rate distortion semantic communication semantic compression

Effects of laser energy on the surface quality and properties of electrodeposited zinc-nickel-molybdenum coatings

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Nanotechnology and Precision Engineering 2023年第3期6卷 18-26页

作者： Tao Ni zhaoyang zhang Yucheng Wu Shuai Yang Laser Technology Institute School of Mechanical EngineeringJiangsu UniversityZhenjiang 212013China

As a substitute for toxic cadmium coatings in the aerospace industry,zinc-nickel coatings have excellent application prospects,and their properties can be improved by adding *** this study,laser-assisted electrodeposition is used to improve the surface quality and properties of Zn–Ni–Mo coatings,with investigation of how laser energy in the range of 0–21.1μJ affects their element content,surface morphology,crystal phase,microhardness,residual internal stress,and corrosion *** laser irradiation accelerates the electrodeposition,refines the grain size,improves the hydrogen adsorption,and reduces the residual tensile stress,and a laser energy of 15.4μJ gives the highest Ni and Mo contents and the lowest Zn content,as well as the optimum surface morphology,microhardness,residual internal stress,and corrosion resistance of the coating.

关键词： Electrodeposition Laser energy Zn-Ni-Mo Surface quality Properties

Delay-Optimal Random Access in Large-Scale Energy Harvesting IoT Networks Based on Mean Field Game

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China Communications 2022年第4期19卷 121-136页

作者： Dezhi Wang Wei Wang zhaoyang zhang Aiping Huang College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou 310027China Zhejiang Provincial Key Laboratory of Information Processing Communication and Networking Zhejiang UniversityHangzhou 310027China

With energy harvesting capability, the Internet of things(IoT) devices transmit data depending on their available energy, which leads to a more complicated coupling and brings new technical challenges to delay optimization. In this paper,we study the delay-optimal random access(RA) in large-scale energy harvesting IoT networks. We model a two-dimensional Markov decision process(MDP)to address the coupling between the data and energy queues, and adopt the mean field game(MFG) theory to reveal the coupling among the devices by utilizing the large-scale property. Specifically, to obtain the optimal access strategy for each device, we derive the Hamilton-Jacobi-Bellman(HJB) equation which requires the statistical information of other ***, to model the evolution of the states distribution in the system, we derive the Fokker-PlanckKolmogorov(FPK) equation based on the access strategy of devices. By solving the two coupled equations,we obtain the delay-optimal random access solution in an iterative manner with Lax-Friedrichs method. Finally, the simulation results show that the proposed scheme achieves significant performance gain compared with the conventional schemes.

关键词： wireless communications energy harvesting random access mean field game

Improved spatio-SNR FGS video coding scheme using motion compensation on enhancement-layer

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Journal of Systems Engineering and Electronics 2006年第1期17卷 37-42页

作者： Jiang Tao zhang zhaoyang Ma Ran Shi Xuli Dept. of Electronic & Information Engineering School of Communication Shanghai Univ. Shanghai 200072 P. R. China

MPEG-4 fine-granularity-scalable （FGS） technology is an effective solution to resolve the network bandwidth varying because FGS provides very fine granular SNR scalability. However, this scalability is obtained with sacrifice of coding efficiency. An one-loop FGS structure is presented based on motion compensation （MC ＋ FGS） to improve the coding efficiency of base FGS. Then it describes and discusses the hybrid spatial-SNR FGS （FGSS） structure that extends SNR scalability of FGS to spatial scalability （spatio-SNR scalability）. FGSS structure inherent the low coding efficiency of FGS structure. Combining MC ＋ FGS structure with FGSS structure, a structure of MC ＋ FGSS structure is obtained which acquires both structures＇ advantages and counteracts both structures＇ defects. Experimental results prove the MC＋ FGSS structure not only obtains fine granular spatio-SNR scalability, but also achieves high coding efficiency.

关键词： fine-granularity-scalable coding efficiency motion compensation spatial scalability MPEG-4.

Multi-Function Uninterrupted Phase-Separation Passing System and its Control Method

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CSEE Journal of Power and Energy Systems 2023年第6期9卷 2332-2343页

作者： Zhou Ni Jiaxin Yuan Feiran Xiao Liwen Peng zhaoyang zhang Yongzhi Min the School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China the School of Electrical Engineering Naval University of EngineeringWuhan 430030China the State Grid Jinan Power Supply Company Jinan 250061China the Department of Electrical and Electronic Engineering Lanzhou Jiaotong UniversityLanzhou 730070China

At present, sudden load changes and terminal voltage fluctuations are two primary problems in the uninterrupted phase-separation passing (UPP) system. To further enhance the reliability of the UPP system and compensate for the voltage sag at the end of the traction power supply network caused by the suddenly connection of locomotive to the power grid, a multi-function uninterrupted phase-separation passing system (MUPPS) and its control strategy are proposed. It has the advantages of linear load change and improving power supply reliability. First, the topology and working principles of a MUPPS are studied;secondly, the current variation characteristics of the bridge arm when the power is continuously supplied by MUPPS during the phase-separation passing are analyzed. Then, the characteristics of a MUPPS to provide reactive power and stabilize the terminal voltage of the traction arm are analyzed. Then, the power transmission characteristics of a MUPPS under emergency working conditions are analyzed. The control strategy for the two conditions is proposed. Finally, simulation analysis and small capacity experiments are conducted. The theoretical analysis and test confirm the correctness and effectiveness of the MUPPS.

关键词： Control strategy high-speed railway MUPPS neutral section

Kinetic mechanism of copper extraction from methylchlorosilane slurry residue using hydrogen peroxide as oxidant

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Chinese Journal of Chemical Engineering 2023年第8期60卷 228-234页

作者： Xiaolin Guo zhaoyang zhang Pengfei Xing Shuai Wang Yibing Guo Yanxin Zhuang School of Metallurgy Northeastern UniversityShenyang 110819China Ecological Environmental Monitoring Center of Liaoning Province Shenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China

Copper was extracted from methylchlorosilane slurry residue by a direct hydrogen peroxide leaching method.A number of experimental parameters were analyzed to determine the extraction efficiency of *** extraction efficiency of copper reached 98.5%under the optimal leaching conditions,such as the hydrogen peroxide concentration of 1.875 mol·L^(-1),the leaching temperature of 323 K,the liquid–solid ratio of 20 ml·g^(-1),and the stirring speed of 300 r·min^(-1).The leaching kinetics of the copper extraction process was then described by the shrinking core *** were two *** first stage was controlled by chemical reactions,while the second stage was controlled by interface transfer and product layer *** activation energy and kinetic control equations were determined,as well as an explanation of the leaching mechanism of copper extraction based on kinetic analysis and materials *** resources can be recovered from the methylchlorosilane slurry residue efficiently and inexpensively with the methods used in this study.

关键词： Methylchlorosilane slurry residue Copper extraction Hydrogen peroxide Kinetics

Exploiting cooperative multipath –Doppler diversity in relay-assisted high-speed train communications

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Chinese Science Bulletin 2014年第35期59卷 5019-5028页

作者： Xiqian Luo zhaoyang zhang Caijun Zhong Xinyu Jin Department of Information Science and Electronic Engineering Zhejiang University

Severe doubly selective channel fading,or the time- and frequency-selective fading,prevailing in highspeed train(HST) communications,has been a critical issue that hinders the improvement of system efficiency and *** this paper,a relay-assisted HST communication system is considered,and a low-complexity but effective scheme is proposed to cooperatively exploit the joint multipath–Doppler diversity of both the direct link and the relay link and thus to mitigate the negative effect of channel fading and improve the system *** particular,using a special precoding structure followed by two-dimensional Fourier transform,the transmit signal is generated which in effect parallelizes the doubly selective fading *** a result,in the transform domain,pointwise combining and equalization,which are of linear complexity,become feasible and diversity gain is *** maximal diversity order is then analyzed under the amplify-and-forward relay settings,which reveals that by cooperative relaying the joint multipath–Doppler diversity of both links can be well *** results verified our analysis.

关键词：通信系统高速列车多普勒多样性继电器频率选择性衰落二维傅立叶变换中继链路