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China Report ASEAN 2018年第1期3卷 18-23页

作者： wang yi China's Foreign

Upholding Multilateralism, Fairness and Justice and Promoting Mutually Beneficial Cooperation——Keynote Speech by State Councilor and Foreign Minister wang yi At the International Seminar on Global Digital Governance

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Peace 2020年第3期 24-26页

作者： wang yi 不详

Beijing,8 September 2020 Distinguished Guests,Colleagues,Ladies and Gentlemen,Friends,We are meeting under the theme"Seizing Digital Opportunities for Cooperation and Development",a topic that is highly relevant.

关键词： Seminar holding Minister

Interview on Current China-US Relations Given by State Councilor and Foreign Minister wang yi to Xinhua News Agency

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Beijing Review 2020年第35期63卷 I0007-I0016页

作者： Xinhua wang yi 不详

State Councilor and Foreign Minister wang yi had an exclusive interview with Xinhua News Agency on August 5,*** following is the ***:US Secretary of State Mike Pompeo asserted in his speech at the Richard Nixon Presidential Library that the policy of engagement with China pursued by successive US administrations since President Nixon's has not produced its goal and has *** people in the United States question his assertion,saying it was more of an“ideological ranf”without any clear or feasible pathway *** is your comment?

关键词：尼克松总统加利福尼亚州中美关系讲话内容新华社历届政府图书馆专访

Synergistic effect of gradient Zn content and multiscale particles on the mechanical properties of Al-Zn-Mg-Cu alloys with coupling distribution of coarse-fine grains

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1392-1405页

作者： Liangliang Yuan Mingxing Guo yi wang Yun wang Linzhong Zhuang Institute of Effectiveness Evaluation of Flying Vehicle Beijing 100085China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China

This study investigated the influence of graded Zn content on the evolution of precipitated and iron-rich phases and grain struc-ture of the alloys,designed and developed the Al–8.0Zn–1.5Mg–1.5Cu–0.2Fe(wt%)alloy with high strength and *** the increase of Zn content,forming the coupling distribution of multiscale precipitates and iron-rich phases with a reasonable matching ratio and dispersion distribution characteristics is *** phenomenon induces the formation of cell-like structures with alternate distribu-tion of coarse and fine grains,and the average plasticity–strain ratio(characterizing the formability)of the pre-aged alloy with a high strength is up to *** reveal the evolution and influence mechanisms of multiscale second-phase particles and the corresponding high formability mechanism of the *** developed coupling control process exhibits considerable potential,revealing remarkable improvements in the room temperature formability of high-strength Al–Zn–Mg–Cu alloys.

关键词： Al–Zn–Mg–Cu alloy iron-rich phase high formability microstructure mechanisms

Performance Study of MIMO-OSTBC Parallel Relay FSO System Based on GFDM

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Chinese Journal of Electronics 2024年第2期33卷 564-572页

作者： Rui ZHOU Yong wang yi wang Key Laboratory of Electromagnetic Wave Information Technology and Metrology of Zhejiang Province College of Information Engineering China Jiliang University State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University

This paper investigates the performance of a new generalized frequency division multiplexing(GFDM)parallel relay free space optical(FSO) communication system using multi-input multi-output(MIMO) orthogonal space-time block codes(OSTBC) scheme. Under the M distribution atmospheric turbulence, taking into account the triple effects of irradiance, pointing errors and path loss, the mathematical expression of system symbol error rate is derived with the help of Meijer G-function. The symbol error performance of GFDM is compared with on-off keying,Gaussian minimum shift keying, polarization shift keying and orthogonal frequency division multiplexing(OFDM)modulation methods. The effects of the MIMO-OSTBC parallel relay scheme on the GFDM system including filter roll down coefficient, the number of transmitting and receiving antennas, the number of relays, normalized beamwidth and jitter variance are analyzed, and the numerical results are verified by Monte Carlo simulation. This work provides a good foundation for engineering applications.

关键词： Monte Carlo methods Transmitting antennas Symbols Receiving antennas Modulation Jitter Transceivers

Beam Training and Tracking in mmWave Communication:A Survey

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China Communications 2024年第6期21卷 1-22页

作者： wang yi Wei Zhiqing Feng Zhiyong Yangtze Delta Region Institute(Quzhou) University of Electronic Science and Technology of ChinaQuzhou 324003China School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Key Laboratory of Universal Wireless Communications Ministry of EducationBeijing University of Posts and TelecommunicationsBeijing 100876China

Communicating on millimeter wave(mmWave)bands is ushering in a new epoch of mobile communication which provides the availability of 10 Gbps high data rate ***,mmWave links are easily prone to short transmission range communication because of the serious free space path loss and the blockage by *** overcome these challenges,highly directional beams are exploited to achieve robust links by hybrid *** aligning the transmitter and receiver beams,*** training,is vitally important to high data rate ***,it may cause huge overhead which has negative effects on initial access,handover,and ***,the mobility patterns of users are complicated and dynamic,which may cause tracking error and large tracking *** efficient beam tracking method has a positive effect on sustaining robust *** article provides an overview of the beam training and tracking technologies on mmWave bands and reveals the insights for future research in the 6th Generation(6G)mobile ***,some open research problems are proposed to realize fast,accurate,and robust beam training and *** hope that this survey provides guidelines for the researchers in the area of mmWave communications.

关键词： 6G beam tracking beam training beamforming mmWave

Differentially private SGD with random features

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 1-23页

作者： wang yi-guang GUO Zheng-chu Polytechnic Institute of Zhejiang University Zhejiang UniversityHangzhou 310015China School of Mathematical Sciences Zhejiang UniversityHangzhou 310058China

In the realm of large-scale machine learning,it is crucial to explore methods for reducing computational complexity and memory demands while maintaining generalization ***,since the collected data may contain some sensitive information,it is also of great significance to study privacy-preserving machine learning *** paper focuses on the performance of the differentially private stochastic gradient descent(SGD)algorithm based on random *** begin,the algorithm maps the original data into a lowdimensional space,thereby avoiding the traditional kernel method for large-scale data storage ***,the algorithm iteratively optimizes parameters using the stochastic gradient descent ***,the output perturbation mechanism is employed to introduce random noise,ensuring algorithmic *** prove that the proposed algorithm satisfies the differential privacy while achieving fast convergence rates under some mild conditions.

关键词： learning theory differential privacy stochastic gradient descent random features reproducing kernel Hilbert spaces

Land use effects on the dynamics of soil C,N and microbes in the water-wind erosion crisscross region of the northern Loess Plateau,China

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Pedosphere 2024年第1期34卷 181-190页

作者： yi wang Chunyue LI Shunjin HU State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China Department of Entomology&Plant Pathology North Carolina State UniversityRaleigh 27695USA

The water-wind erosion crisscross region of the northern Loess Plateau in China is under constant pressure from severe erosion due to its windy and dry climate and intensive human activities. Identifying sustainable land use patterns is key to maintaining ecosystem sustainability in the area. Our aim was to appraise the impacts of different land use regimes on the dynamics of soil total organic C(TOC), total N(TN), and microbes in a typical watershed in the northern Loess Plateau to identify suitable land use types that can maintain soil fertility and sustainability. A field experiment was performed in Liudaogou watershed in Shenmu City, Shaanxi Province, China, where the dynamics of soil TOC and TN, microbial biomass C and N, microbial respiration, and net N mineralization in six typical land use types, dam land, rainfed slope land, deciduous broadleaf forest, evergreen coniferous forest, shrubland, and grassland,were measured in three different growing seasons. Land use type and season significantly affected TOC, TN, and the dynamics of microbial biomass and activity. As the most anthropogenically disturbed land use pattern, dam land was an optimal land use pattern for TOC sequestration due to its higher TOC and TN, but lower microbial activity. Soil TOC, TN, and microbial properties demonstrated a decreasing trend after natural grassland was converted to shrubland,forest, and rainfed slope land. Shrubland with exotic N-fixing Korshinsk peashrub(Caragana korshinskii Kom.) can maintain TOC, TN, and microbial properties similar to those in grassland. Soil TOC, NH_(4+)^(-)N, TN, moisture, and extractable C were the principal indexes for soil microbial biomass and activity and explained 88.90% of the total variance. Thus, grassland was the optimal land use pattern in the water-wind erosion crisscross region of the northern Loess Plateau to maintain ecosystem stability and sustainability.

关键词： grassland microbial activity microbial biomass total organic C total N watershed

Acylfluorination of enynes via phosphine and silver catalysis

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Chinese Chemical Letters 2024年第8期35卷 260-264页

作者： Yu Mao yilin Liu Xiaochen wang Shengyang Ni yi Pan yi wang State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

This work describes intermolecular acylfluorination of gem-difluoroenynes using acyl fluorides as both acyl source and fluorine ***-substituted allenones or furans could be selectively achieved via phosphine and silve... 详细信息

关键词： Phosphine catalysis Silver catalysis Difunctionalization Allenone Furan Trifluoromethyl

Small-signal Stability Constrained Optimal Power Flow Considering Eigenvalue Distribution

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1052-1062页

作者： Zheng Huang Kewen wang yi wang Jing Han Jun Liang the School of Electrical and Information Engineering Zhengzhou UniversityZhengzhou 450001China Cardiff University Cardiff CF243AAU.K.

In the existing small-signal stability constrained op-timal power flow(SSSC-OPF)algorithms,only the rightmost ei-genvalue or eigenvalues that do not satisfy a given threshold,e.g.,damping ratio threshold and real-part threshold of eigen-value,are considered in the small-signal stability *** effect of steady-state,i.e.,operating point,changes on eigen-values is not fully taken into *** this paper,the small-signal stability constraint that can fully reflect the eigenvalue change and system dynamic performance requirement is formed by analyzing the eigenvalue distribution on the complex *** small-signal stability constraint is embedded into the standard optimal power flow model for generation *** simultaneous solution formula of the SSSC-OPF is es-tablished and solved by the quasi-Newton approach,while pen-alty factors corresponding to the eigenvalue constraints are de-termined by the stabilization degree of constrained *** improve the computation speed,a hybrid algorithm for ei-genvalue computation in the optimization process is proposed,which includes variable selection for eigenvalue estimation and strategy selection for eigenvalue *** effectiveness of the proposed algorithm is tested and validated on the New England 10-machine 39-bus system and a modified practical 68-machine 2395-bus system.

关键词： Damping ratio eigenvalue optimal power flow quasi-Newton approach sensitivity small-signal stability