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Microbe-induced gene silencing explores interspecies RNAi and opens up possibilities of crop protection

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Science China(Life Sciences) 2024年第3期67卷 626-628页

作者： Rongxiang fang State Key Laboratory of Plant Genomics Institute of MicrobiologyChinese Academy of Sciencesand National Plant Gene Research CenterBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

In most eukaryotes, small RNA(sRNA)-mediated RNA silencing(or RNA interference, RNAi) is an evolutionarily conserved mechanism that regulates gene expression in a sequence-specific ***, s RNAs are produced by the RNase III enzymes Dicers and then incorporated into Argonaute(AGO) proteins to regulate gene expression by mRNA degradation.

关键词： protection conserved manner

A disk I/O optimized system for concurrent graph processing jobs

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Frontiers of Computer Science 2024年第3期18卷 13-29页

作者： Xianghao XU fang WANG Hong JIANG Yongli CHENG Dan FENG Peng fang School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Department of Computer Science&Engineering University of Texas at ArlingtonArlingtonTX 76019USA College of Computer and Data Science Fuzhou UniversityFuzhou 350108China zhejiang Lab Hangzhou 311121China

In order to analyze and process the large graphs with high cost efficiency,researchers have developed a number of out-of-core graph processing systems in recent years based on just one commodity *** the other hand,with the rapidly growing need of analyzing graphs in the real-world,graph processing systems have to efficiently handle massive concurrent graph processing(CGP)***,due to the inherent design for single graph processing job,existing out-of-core graph processing systems usually incur unnecessary data accesses and severe competition of I/O bandwidth when handling the CGP *** this paper,we propose GraphCP,a disk I/O optimized out-of-core graph processing system that efficiently supports the processing of CGP *** proposes a benefit-aware sharing execution model to share the I/O access and processing of graph data among the CGP jobs and adaptively schedule the graph data loading based on the states of vertices,which efficiently overcomes above challenges faced by existing out-of-core graph processing ***,GraphCP adopts a dependency-based future-vertex updating model so as to reduce disk I/Os in the future *** addition,GraphCP organizes the graph data with a Source-Sorted Sub-Block graph representation for better processing capacity and I/O access *** evaluation results show that GraphCP is 20.5×and 8.9×faster than two out-of-core graph processing systems GridGraph and Graphz,and 3.5×and 1.7×faster than two state-of-art concurrent graph processing systems Seraph and GraphSO.

关键词： graph processing disk I/O concurrent jobs

Planning an adaptive reuse development of underutilized urban underground infrastructures:A case study of Qingdao,China

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Underground Space 2024年第1期14卷 18-33页

作者： Yong-Kang Qiao fang-Le Peng Yun-Hao Dong Chun-fang Lu Research Center for Underground Space&Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

Urban underground infrastructures(UUIs)are a vital component of built capital for urban ***,many cities are now home to a multitude of disused or underutilized UUIs,not least aged purpose-built underground facilities,causing a waste of valuable underground space resource *** the process of urban renewal,adaptive reuse can be an attractive solution to breathe new life into underutilized UUIs,while addressing some of the modern problems of the built environment by an economically feasible ***,there is a prevalent absence in the current literature of the overarching planning and decision-making approaches for an adaptive reuse development of underutilized *** the intention of addressing this shortfall,this paper first lays out development strategies,then sets the generic patterns for adaptive reuse of disused or underutilized *** the city of Qingdao,China as a case study,detailed planning and decision-making approaches with the aid of multi-source data and spatial analysis tools are *** is anticipated that the findings of this research will assist the adaptive reuse development of UUIs in providing theoretical guidance and empirical evidence,thereby enhancing the role of urban underground space use in contributing to urban revitalization and urban sustainability.

关键词： Urban underground infrastructures Underutilized Adaptive reuse Planning Urban renewal

Tunable Fiber Gratings and Their Applications

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光学学报 2003年第S1期23卷 223-224页

作者： z. fang L. zhao L. Li K. Gao Y. zhou J. Geng R. Qu G. Chen Shanghai Institute of Optics and Fine Mechanics The Chinese Academy of SciencesP.R. ChinaShanghai Institute of Optics and Fine MechanicsThe Chinese Academy of SciencesP.R. ChinaShanghai Institute of Optics and Fine MechanicsThe Chinese Academy of SciencesP.R. ChinaShanghai Institute of Optics and Fine MechanicsThe Chinese Academy of SciencesP.R. ChinaShanghai Institute of Optics and Fine MechanicsThe Chinese Academy of SciencesP.R. ChinaShanghai Institute of Optics and Fine MechanicsThe Chinese Academy of SciencesP.R. ChinaShanghai Institute of Optics and Fine MechanicsThe Chinese Academy of SciencesP.R. ChinaShanghai Institute of Optics and Fine MechanicsThe Chinese Academy of SciencesP.R. China

Some practical research topics on tunable fiber gratings in author's group are presented, including tuning speed, tuning range, tuning characteristics of gratings in HB fiber, and the tunability of the line-width. The... 详细信息

关键词： been of in as FBG were Tunable Fiber Gratings and Their Applications than have EDFA for that

A low-frequency and broadband wave-insulating vibration isolator based on plate-shaped metastructures

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1171-1188页

作者： Wei WEI Feng GUAN Xin fang College of Intelligent Science National University of Defense TechnologyChangsha410073China Naval Research Academy Beijing100161China

A metamaterial vibration isolator,termed as wave-insulating isolator,is proposed,which preserves enough load-bearing capability and offers ultra-low and broad bandgaps for greatly enhanced wave *** consists of plate-shaped metacells,whose symmetric and antisymmetric local resonant modes offer several low and broad mode bandgaps although the complete bandgap remains high and *** bandgap mechanisms,vibration isolation properties,effects of key parameters,and robustness to complex conditions are *** experimentally demonstrated,the wave-insulating isolator can improve the vibration insulation in the ranges of[50 Hz,180 Hz]and[260 Hz,400 Hz]by 15 dB and 25 dB,respectively,in contrast to the conventional isolator with the same first resonant frequency.

关键词： metamaterial and metastructure vibration isolation bandgap wave insulation plate

Non-dimensional analysis on blast wave propagation in foam concrete:Minimum thickness to avoid stress enhancement

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Defence Technology（防务技术） 2024年第6期36卷 30-46页

作者： Ya Yang Xiangzhen Kong Qin fang State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing 210007JiangsuChina

Foam concrete is a prospective material in defense engineering to protect structures due to its high energy absorption capability resulted from the long plateau ***,stress enhancement rather than stress mitigation may happen when foam concrete is used as sacrificial claddings placed in the path of an incoming blast *** investigate this interesting phenomenon,a one-dimensional difference model for blast wave propagation in foam concrete is firstly proposed and numerically solved by improving the second-order Godunov *** difference model and numerical algorithm are validated against experimental results including both the stress mitigation and the stress *** difference model is then used to numerically analyze the blast wave propagation and deformation of material in which the effects of blast loads,stress-strain relation and length of foam concrete are *** particular,the concept of minimum thickness of foam concrete to avoid stress enhancement is ***,non-dimensional analysis on the minimum thickness is conducted and an empirical formula is proposed by curve-fitting the numerical data,which can provide a reference for the application of foam concrete in defense engineering.

关键词： Foam concrete Blast wave propagation Non-dimensional analysis Stress enhancement

A New Method for Solving Nonlinear Partial Differential Equations Based on Liquid Time-Constant Networks

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Journal of Systems Science & Complexity 2024年第2期37卷 480-493页

作者： SUN Jiuyun DONG Huanhe fang Yong College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

In this paper,physics-informed liquid networks(PILNs)are proposed based on liquid time-constant networks(LTC)for solving nonlinear partial differential equations(PDEs).In this approach,the network state is controlled via ordinary differential equations(ODEs).The significant advantage is that neurons controlled by ODEs are more expressive compared to simple activation *** addition,the PILNs use difference schemes instead of automatic differentiation to construct the residuals of PDEs,which avoid information loss in the neighborhood of sampling *** this method draws on both the traveling wave method and physics-informed neural networks(PINNs),it has a better physical ***,the KdV equation and the nonlinear Schr¨odinger equation are solved to test the generalization ability of the *** the best of the authors’knowledge,this is the first deep learning method that uses ODEs to simulate the numerical solutions of PDEs.

关键词： Nonlinear partial differential equations numerical solutions physics-informed liquid networks physics-informed neural networks

Adaptive Algorithms on Maximizing Monotone Nonsubmodular Functions

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Journal of the Operations Research Society of China 2024年第2期12卷 428-445页

作者： Bin Liu Hui Su Shu-fang Gong Qi-zhi fang School of Mathematical Sciences Ocean Universityof ChinaQingdao266100ShandongChina

Submodular optimization is widely used in large *** order to speed up the problems solving,it is essential to design low-adaptive algorithms to achieve acceleration in *** general,the function values are given by a value oracle,but in practice,the oracle queries may consume a lot of ***,how to strike a balance between optimizing them is *** this paper,we focus on maximizing a normalized and strictly monotone set function with the diminishing-return ratio under a cardinality constraint,and propose two algorithms to deal with *** apply the adaptive sequencing technique to devise the first algorithm,whose approximation ratio is arbitrarily close to 1-e^(-γ)in O(logn·log(log k/γ)) adaptive rounds,and requires O(logn^(2)·log(log k/γ)) *** by adding preprocessing and parameter estimation steps to the first algorithm,we get the second *** second algorithm trades a small sacrifice in adaptive complexity for a significant improvement in query *** the same approximation and adaptive complexity,the query complexity is improved *** the best of our knowledge,this is the first paper of designing adaptive algorithms for maximizing a monotone function using the diminishing-return ratio.

关键词： Approximation algorithm Adaptivity Nonsubmodular maximization Cardinality constraint

A SIMPLIFIED SUBREGULAR SOLUTION MODEL DESCRIBING THE ACTIVITES OF MgCl_2 IN BOTH KCl-MgCl _2-LiCl AND CaCl_2-MgCl_2-NaCl MOLTEN SALT SYSTEMS

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 1159-1163页

作者： Q.R.zhang,Y.G.Li and z.fang Department of Chemistry, Central South University of Technology, Changsha 410083, China

A simplified subregular solution model was developed for describing the activities of MgCl 2 in both KCl MgCl 2 LiCl and CaCl 2 MgCl 2 NaCl systems on the assumption that the electrolytes in the solution are treated as independent particles in stead of their ion forms and the interchange energy between the KCl LiCl (or CaCl 2 NaCl) pair is ignored as compared to those of the KCl MgCl 2(or CaCl 2 MgCl 2) and MgCl 2 LiCl (or MgCl 2 NaCl) pairs. The calculating results on the model agree with the observed very well.

关键词： activity MgCl 2 electrolyte solution model interchange energy