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Scalability Analysis of Request Scheduling in Cloud Computing

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Tsinghua Science and Technology 2019年第3期24卷 249-261页

作者： Chao Xue Chuang Lin Jie hu Tsinghua National Laboratory for Information Science and Technology (TNList) & Department of Computer Science and Technology Tsinghua University

Rapid advancement of distributed computing systems enables complex services in remote computing clusters. Massive applications with large-scale and disparate characteristics also create high requirements for computing systems. Cloud computing provides a series of novel approaches to meet new trends and ***, some scalability issues have to be addressed in the request scheduling process and few studies have been conducted to solve these problems. Thus, this study investigates the scalability of the request scheduling process in cloud computing. We provide a theoretical definition of the scalability of this process. By modeling the scheduling server as a stochastic preemptive priority queue, we conduct a comprehensive theoretical and numerical analysis of the scalability metric under different structures and various environment configurations. The comparison and conclusion are expected to shed light on the future design and deployment of the request scheduling process in cloud computing.

关键词： cloud computing request scheduling scalability model evaluation

Optimal Combinations and Variable Departure Intervals for Micro Bus System

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Tsinghua Science and Technology 2017年第3期22卷 282-292页

作者： Jiaoyang Li Jianming hu Yi Zhang Department of Automation Tsinghua UniversityBeijing 100084China

It is becoming increasingly difficult for Chinese citizens to access traditional public transport because of overcrowded community structures. Therefore, novel ideas are required to improve the transport system. In this respect, this study considers the design of a public transport scheduling model for a micro system. The model aims to minimize passenger waiting time and maximize number of passengers one bus carries, by simultaneously optimizing departure intervals and use of traditional and rapid buses. The model is superior to traditional models, as it analyzes the phenomena of vehicle overtaking, vehicle capacity limit, and passenger determination uncertainty. In addition, the model is a sophisticated nonlinear multi-objective optimization problem and contains more than one type of decision variable, therefore two composite algorithms, HPSO and GAPSO, are proposed, which are improvements of the Genetic Algorithm （GA） and Particle Swarm Optimization （PSO）. These two algorithms are compared to the classical GA with respect to stability and effect, and the results show them to be strong in both respects. In addition, the simultaneous optimization method has evident advantages compared to single-method optimizations.

关键词： bus scheduling optimization model rapid bus Particle Swarm Optimization (PSO) Genetic Algorithm(GA)

Incorporating a rainfall intensity modification factorγinto the I a-S Relationship in the NRCS-CN method

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International Soil and Water Conservation Research 2020年第3期8卷 237-244页

作者： Pengcheng hu Jialiang Tang Jihui Fan Shumiao Shu Zhaoyong hu Bo Zhu Key Laboratory of Mountain Environment Evolution and Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu610041China University of Chinese Academy of Sciences BeijingChina

The Natural Resources Conservation Service runoff curve number(NRCS-CN)method is widely used to simulate direct runoff,but the impact of rainfall intensity has not been *** this study,a rainfall intensity modification factor(γ)was incorporated into the Ia-S relationship of the NRCS-CN method,and the modified method(NRCS-CN-γ)was compared with the NRCS-CN method withλ=0.2 andλ=0.05 in three watersheds of the Walnut Gulch Experimental Watershed(WGEW).The results showed that for 2016-2018 period,the simulation performance of the NRCS-CN-γmethod was close to the NRCS-CN(λ=0.05)method and better than the NRCS-CN(λ=0.2)*** the new data(2009 data with high variance)was added,the significant improvement was observed by NRCS-CN-γmethod with all the evaluation parameters being the best in the three watersheds,indicating a more adapted capa-bility of the modified method with highly uneven rainfall *** covariance between rainfall intensity and the simulated runoff were 19.01,15.14,and 16.35 for the three methods,*** the optimal CN changed,the relative errors representing CN sensitivity were 6.25,6.49 and 17.39 for the methods,*** is suggested that the NRCS-CN-γmethod outperformed the other two methods and could contribute to a more accurate estimation of direct runoff where rainfall intensity greatly varied,especially in monsoon region or under the context of climate change.

关键词： Climate change Rainfall intensity Runoff NRCS-CN method CN sensitivity

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语用混沌论探讨

外语学刊 2009年第2期 78-82页

作者：胡加圣上海外国语大学上海200083

基于对混沌论/复杂论和语用学的基本观点和观察,本文提出语用混沌论观点,并且在此基础之上分析语言使用中的力动力场的存在及其对语用产生的影响。

关键词：语用学混沌论力动力场

Enhancing Differential Evolution with Commensal Learning and Uniform Local Search

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Chinese Journal of Electronics 2017年第4期26卷 725-733页

作者： PENG hu WU Zhijian DENG Changshou State Key Laboratory of Software Engineering School of Computer Wuhan University School of Information Science and Technology Jiujiang University

Differential evolution(DE) is a popular and powerful evolutionary algorithm for global optimization problems. However, the combination of mutation strategies and parameter settings of DE is problem dependent and choosing the suitable one is a challenge work and timeconsuming. In addition, the deficiency in local exploitation also has a significant influence on the performance of *** order to solve these problems, a DE variant with Commensal learning and uniform local search(CUDE) has been proposed in this paper. In CUDE, commensal learning is proposed to adaptively select optimal mutation strategy and parameter setting simultaneously under the same criteria. Moreover, uniform local search enhances exploitation ability. Comprehensive experiment results on all the CEC2013 test suite and comparison with the state-of-the-art DE variants indicate that the CUDE is very competitive.

关键词： Differential evolution Commensal learn ing Uniform local search Global optimization

Multi-threaded code generation from Signal program to OpenMP

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Frontiers of Computer Science 2013年第5期7卷 617-626页

作者： Kai hu Teng ZHANG Zhibin YANG State Key Laboratory of Software Development Environment Beihang University Beijing 100191 China School of Computer Science and Engineering Beihang University Beijing 100191 China IRIT-CNRS Universite de Toulouse Toulouse 31062 France

The use of multi-core processors will become a trend in safety critical systems. For safe execution of multi- threaded code, automatic code generation from formal spec- ification is a desirable method. Signal, a synchronous lan- guage dedicated for the functional description of safety crit- ical systems, provides soundness semantics for determinis- tic concurrency. Although sequential code generation of Sig- nal has been implemented in Polychrony compiler, deter- ministic multi-threaded code generation strategy is still far from mature. Moreover, existing code generation methods use certain multi-thread library, which limits the cross plat- form executions. OpenMP is an application program inter- face （API） standard for parallel programming, supported by several mainstream compilers from different platforms. This paper presents a methodology translating Signal program to OpenMP-based multi-threaded C code. First, the intermedi- ate representation of the core syntax of Signal using syn- chronous guarded actions is defined. Then, according to the compositional semantics of Signal equations, the Signal pro- gram is synthesized to dependency graph （DG）. After par- allel tasks are extracted from dependency graph, the Signal program can be finally translated into OpenMP-based C code which can be executed on multiple platforms.

关键词： multi-thread synchronous language Signal,code generation OpenMP

THE CONDITIONAL DIAGNOSABILITY OF ShuFFLE-CUBES

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Journal of Systems Science & Complexity 2010年第1期23卷 81-90页

作者： Min XU Xiaodong hu Songpu SHANG School of Mathematical Sciences Beijing Normal University Laboratory of Mathematics and Complex Systems Ministry of Education Beijing 100875 China Institute of Applied Mathematics MADIS Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China College of Mathematics and Information Science North China University of Water Conservancy and Electric Power Zhengzhou Henan 450008 China

In the application of multiple-processor systems some processors or links in a system maynot function properly,thus the fault diagnosis is one of the most important issues in the analysisand maintenance of those *** the practical fault diagnosis systems,the probability that allneighboring processors of a processor are faulty simultaneously is very ***,the conditionaldiagnosability,which is a new metric for evaluating such systems,assumes that every fault set doesnot contain all neighbors of any processor in the *** this paper,the authors show that then-dimensional shuffle-cube has the conditional diagnosability of 4n-15 for n = 2 (mod 4) and n ≥ 10.

关键词： Conditional diagnosability fault diagnosis shuffle-cubes.

Influence of multiple structural parameters on interior ballistics based on orthogonal test methods

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Defence Technology（防务技术） 2019年第5期15卷 690-697页

作者： Chao-bin hu Xiao-bing Zhang School of Energy and Power Engineering Nanjing University of Science and Technology

Influence of multiple structural parameters on the performance of a gun launch system driven by highpressure reactive gases is important for structural design and performance adjustment.A coupled lumped parameter model was utilized to predict the propellant combustion,and a dynamic finite element method was applied to approximate the mechanical interactions between the projectile and the *** combustion and the mechanical interactions were coupled through a user subroutine interface in *** correctness and the capability of the finite element approximations in capturing small structural changes were validated by comparing predicted resistance with *** on the coupled model,the influence of structural parameters of a medium-caliber gun on the system performance was *** order to reduce the research costs,orthogonal tests were designed to investigate the comprehensive effects of the *** to statistical analysis,the important order of the structural parameters on the launching process was *** results indicate that the influence of the width of the rotating band stands out among the studied parameters in the *** work provides a method to investigate the influence of multiple parameters on system performance and gives guidance for controlling the system performance.

关键词： Multiple parameters Coupled model Combustion Sensitivity analysis Orthogonal test

GraphFlow+:Exploiting Conversation Flow in Conversational Machine Comprehension with Graph Neural Networks

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Machine Intelligence Research 2024年第2期21卷 272-282页

作者： Jing hu Lingfei Wu Yu Chen Po hu Mohammed J.Zaki School of Computer Science Central China Normal UniversityWuhan 430079China Pinterest San Francisco 94016USA Meta Mountain View 94039USA Rensselaer Polytechnic Institute Troy 12180USA

The conversation machine comprehension(MC)task aims to answer questions in the multi-turn conversation for a single ***,recent approaches don’t exploit information from historical conversations effectively,which results in some references and ellipsis in the current question cannot be *** addition,these methods do not consider the rich semantic relationships between words when reasoning about the passage *** this paper,we propose a novel model GraphFlow+,which constructs a context graph for each conversation turn and uses a unique recurrent graph neural network(GNN)to model the temporal dependencies between the context graphs of each ***,we exploit three different ways to construct text graphs,including the dynamic graph,static graph,and hybrid graph that combines the *** experiments on CoQA,QuAC and DoQA show that the GraphFlow+model can outperform the state-of-the-art approaches.

关键词： Conversational machine comprehension(MC) reading comprehension question answering graph neural networks(GNNs) natural language processing(NLP)