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ForkXplorer:an approach of fork summary generation

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Frontiers of Computer Science 2022年第2期16卷 1-15页

作者： zhang zhang Xinjun MAO Chao zhang Yao LU Key Laboratory of Software Engineering for Complex Systems College of ComputerNational University of Defense TechnologyChangsha 410073China

Pull-based development has become an important paradigm for distributed software *** this model,each developer independently works on a copied repository(i.e.,a fork)from the central *** is essential for developers to maintain awareness of the state of other forks to improve collaboration *** this paper,we propose a method to automatically generate a summary of a *** first use the random forest method to generate the label of a fork,i.e.,feature implementation or a bug *** on the information of the fork-related commits,we then use the TextRank algorithm to generate detailed activity information of the ***,we apply a set of rules to integrate all related information to construct a complete fork *** validate the effectiveness of our method,we conduct 30 groups of manual experiment and 77 groups of case studies on *** propose Fea_(avg)to evaluate the performance of Fea_(avg)the generated fork summary,considering the content accuracy,content integrity,sentence fluency,and label extraction *** results show that the average of of the fork summary generated by this method is *** than 63%of project maintainers and the contributors believe that the fork summary can improve development efficiency.

关键词： open source software pull-based development fork summary distributed cooperative development

Numerical Modeling of Friction Stir Welding Process by Using Rate-dependent Constitutive Model

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Journal of Materials Science & Technology 2007年第1期23卷 73-80页

作者： Hongwu zhang Zhao zhang State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering Mechanics Dalian University of Technology Dalian 116024 China

Rate-dependent constitutive model was used to simulate the friction stir welding process. The effect of the viscosity coefficient and the process parameters on the material behaviors and the stress distributions around the pin were studied. Results indicate that the stress in front of the pin is larger than that behind the pin. The difference between the radial/circumferential stress in front of the pin and that behind it becomes smaller when the material gets closer to the top surface. This difference increases with increasing the viscosity coefficient and becomes smaller when the welding speed decreases. The variation of the angular velocity does not significantly affect the difference.

关键词： Friction stir welding Finite element method Viscosity

Simplified calculation of UWB signal transmitting through a finitely conducting slab

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Journal of Systems Engineering and Electronics 2008年第6期19卷 1070-1075页

作者： Wang Yang zhang Naitong zhang Qinyu zhang Zhongzhao Communication Research Center Harbin Inst. of Technology Harbin 150001 P. R. China

A simplified closed-form analytic solution for UWB impulse signal transmitting through a finitely conducting slab is proposed. The approach first requires evaluating the impulse response of the slab and then convolving it with the specified incident field waveform. To obtain the impulsive transmitting field, either for vertical or horizontal polarization, approximations to the refraction coefficients and propagation loss are made, which can be proved to be accurate enough, comparing with their frequency domain solutions. Thereby, it permits simplified closed-form expressions in the time domain for both terms. The resulting transient response for the transmitting impulse field is then given by convolution of the time domMn refraction coefficients and time domain propagation loss. A numerical example of an incident monocyele transmitting through a slab using this technique, is presented, to illustrate the effective use of the method.

关键词： ultra-wide band time domain indoor propagation channel multipath.

Characterizing Ultra-wide Band indoor line-of-sight wireless channel

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Journal of Systems Engineering and Electronics 2007年第4期18卷 673-678,697页

作者： Wang Yang zhang Naitong zhang Qinyu zhang Zhongzhao Communication Research Center Harbin Institute of Technology Harbin 150001 P. R. China

By exploring the deterministic characteristics of the measurement data, a new propagation model with two deterministic clusters and stochastic arriving rays within each cluster is proposed. When considering the cumulative distribution function （CDF） of the three key channel statistics, the proposed model fits the measurement data better than SV/IEEE 802.15.3, a model which is known as a standard model for UWB indoor propagation channel. Therefore, with the additional knowledge of the specific environment geometry, the proposed model generating impulse responses ＂resemble＂ the measured channel impulse responses better than IEEE model. Moreover, the proposed model＇s parameters obtaining procedure is simplified by utilizing simple parameters of the environment.

关键词： UWB wireless channel propagation characteristic indoor channel.

Deconvolution techniques for characterizing indoor UWB wireless channel

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Journal of Systems Engineering and Electronics 2008年第4期19卷 688-693页

作者： Wang Yang zhang Naitong zhang Qinyu zhang Zhongzhao Communication Research Center Harbin Inst. of Technology Harbin 150001 P. R. China

A deconvolution algorithm is proposed to account for the distortions of impulse shape introduced by propagation process. By finding the best correlation of the received waveform with the multiple templates, the number of multipath components is reduced as the result of eliminating the ＂phantom paths＂, and the captured energy increases. Moreover, it needs only a single reference measurement in real measurement environment （do not need the anechoic chamber）, which by far simplifies the templates acquiring procedure.

关键词： ultra-wide band channel model CLEAN algorithm CIR deconvolution.

Modeling droplet vaporization and combustion with the volume of fluid method at a small Reynolds number

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第5期13卷 361-374页

作者： Xiao-bin zhang Wei zhang Xue-jun zhang Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

The volume of fluid(VOF) formulation is applied to model the combustion process of a single droplet in a hightemperature convective air free stream *** calculations solve the flow field for both phases,and consider the droplet deformation based on an axisymmetrical *** chemical reaction is modeled with one-step finite-rate mechanism and the thermo-physical properties for the gas mixture are species and temperature dependence.A mass transfer model applicable to the VOF calculations due to vaporization of the liquid phases is developed in consideration with the fluctuation of the liquid *** model is validated by examining the burning rate constants at different convective air temperatures,which accord well with experimental data of previous *** phenomena from the simulations,such as the transient history of droplet deformation and flame structure,are also qualitatively accordant with the descriptions of other numerical ***,a different droplet deformation mechanism for the low Reynolds number is explained compared with that for the high Reynolds *** calculations verified the feasibility of the VOF computational fluid dynamics(CFD) formulation as well as the mass transfer model due to vaporization.

关键词： Droplet Vaporization Combustion process Volume of fluid(VOF) Numerical simulation

KaKs_Calculator 3.0:Calculating Selective Pressure on Coding and Non-coding Sequences

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Genomics, Proteomics & Bioinformatics 2022年第3期20卷 536-540页

作者： zhang zhang National Genomics Data Center Beijing Institute of GenomicsChinese Academy of SciencesBeijing 100101China CAS Key Laboratory of Genome Sciences and Information Beijing Institute of GenomicsChinese Academy of SciencesBeijing 100101China China National Center for Bioinformation Beijing 100101China University of Chinese Academy of Sciences Beijing 100049China

KaKs_Calculator 3.0 is an updated toolkit that is capable of calculating selective pressure on both coding and non-coding *** to the nonsynonymous/synonymous substitution rate ratio for coding sequences,selection on non-coding sequences can be quantified as the ratio of non-coding nucleotide substitution rate to synonymous substitution rate of adjacent coding *** testified on empirical data,KaKs_Calculator 3.0 shows effectiveness to detect the strength and mode of selection operated on molecular sequences,accordingly demonstrating its great potential to achieve genome-wide scan of natural selection on diverse sequences and identification of potentially functional elements at a whole-genome *** package of KaKs_Calculator 3.0 is freely available for academic use only at https://***/biocode/tools/BT000001.

关键词： KaKs_Calculator Selective pressure Substitution Coding Non-coding

Study on group air to ground attack-defends hierarchical dynamic decision-making

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Journal of Systems Engineering and Electronics 2007年第3期18卷 540-544页

作者： zhang Li zhang An zhang Yongfang Shi Zhifu Dept. of System and Control Engineering School of Electronic and Information~ Northwest Polytechnic Univ.. Xi'an 710072 P R. China

As to oppositional, multi-objective and hierarchical characteristic of air formation to ground attackdefends campaign, and using dynamic space state model of military campaign, this article establishes a principal and subordinate hierarchical interactive decision-making way, the Nash-Stackelberg-Nash model, to solve the problems in military operation, and find out the associated best strategy in hierarchical dynamic decision-making. The simulating result indicate that when applying the model to air formation to ground attack-defends decision-making system, it can solve the problems of two hierarchies, dynamic oppositional decision-making favorably, and reach preferable effect in battle. It proves that the model can provide an effective way for analyzing a battle,

关键词： dynamic game theory Nash-Stackelberg-Nash strategy hierarchical decision-making attack-defends antagonize.

Twin boundary： Controllable interface to fatigue cracking

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Journal of Materials Science & Technology 2017年第7期33卷 603-606页

作者： Zhefeng zhang Linlin Li Zhenjun zhang Peng zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Twin boundaries（TBs） are key factors influencing the mechanical properties of crystalline materials. We have investigated the intrinsic fatigue cracking mechanisms of TBs during the past decade. The effects of TB orientations on the fatigue cracking mechanisms were revealed via cyclic deformation of a series of grown Cu bicrystals with a sole TB. Furthermore, the combined effects of crystallographic orientation and stacking fault energy（SFE） on the fatigue cracking mechanisms were clarified through cyclic deformation of polycrystalline Cu and Cu alloys. Both developments were reviewed in this report which will provide implications to optimize the interfacial design for the improvement of fatigue performance of metallic materials.

关键词： Fatigue cracking Twin boundary Stacking fault energy Orientation