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MULtI-fACILItY ORDERED MEDIAN PROBLEMS IN DIRECtED NEtWORKS

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Journal of Systems Science & Complexity 2011年第1期24卷 61-67页

作者： Huajun tANG t. C. Edwin cheng C. t. NG faculty of Management and Administration Macao University of Science and Technology Macao China Department of Logistics and Maritime Studies The Hong Kong Polytechnic University Hong Kong China

this paper uses a finite dominating set （fDS） to investigate the multi-facility ordered median problem （OMP） in a strongly connected directed network. the authors first prove that the multi-facility OMP has an fDS in the node set, which not only generalizes the fDS result provided by Kalcsics, et al. （2002）, but also extends the fDS result from the single-facility Case to the multiple case, filling an important gap. then, based on this fDS result, the authors develop an exact algorithm to solve the problem. However, if the number of facilities is large, it is not practical to find the optimal solution, because the multi-facility OMP in directed networks is NP-hard. Hence, we present a constant-approximation algorithm for the p-median problem in directed networks. finally, we pose an open problem for future research.

关键词： Algorithms finite dominating sets multi-facility ordered median problem pseudoequilibria.

EffECt Of SEN DESIGN ON SURfACE fLUCtUAtION AND SOLIDIfYING SHELL IN SLAB MOLD AND ItS OPtIMIZAtION

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Acta Metallurgica Sinica(English Letters) 2008年第5期21卷 341-350页

作者： D.f. Wu S.S. cheng School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

turbulent flow and heat transfer coupled with solidification in slab continuous casting mold was studied by numerical simulation method. Volume of fluid （VOf） model is used to solve steel-air two-phase flow problem and enthalpy-porosity scheme is introduced to solve the fluid flow problem involving solidification. Contributions of various nozzle port angles and port widths and heights on the free surface fluctuation and the thickness of solidifying shell in slab mold were particularly investigated, based on which the structure of submerged entry nozzle was optimized. flow inside the common nozzle port cannot fill the entire outlet area, having a recirculation in the upper portion of the port, which is enlarged for the nozzle port with both larger height and width. Results show that the flow in mold cavity is mainly controlled by the nozzle port angle. the increase of the angle of upper face of the port to shape a roughly streamlined inner-wall improves the effective area fraction of the nozzle, resulting in less jet impingement, weaker free surface turbulence and thicker solidifying steel shell.

关键词： Slab continuous casting Submerged entry nozzle Optimization Numerical simulation

New targets for controlling Ebola virus disease

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National Science Review 2015年第3期2卷 266-267页

作者： f.Xiao-feng Qin cheng-Yu Jiang taijiao Jiang Genhong cheng Center for Systems Medicine Institute of Basic Medical Sciences Chinese Academy of Medical Sciences and Peking Union Medical College State Key Laboratory of Medical Molecular Biology Institute of Basic Medical SciencesChinese Academy of Medical Sciences Department of Biochemistry and Molecular Biology Peking Union Medical College Tsinghua University Key Laboratory of Protein and Peptide Pharmaceuticals Institute of Biophysics Chinese Academy of Sciences Department of Microbiology Immunology and Molecular Genetics University of California

EBOV infects multiple diferent cell types and replicates rapidly in vivo[1].Due to its long ilamentous structure,EBOV is internalized by macropinocytosis ater cell surface receptor binding by the viral glycoprotein(GP).Unlike many other enveloped viruses,EBOV entry process involves multiple steps of traversing of the virion through endosomal vesicle route before its nuclear core is released into cell cytoplasm for replication[2].

关键词： New targets for controlling Ebola virus disease GP tPC

ARE tHE SO-CALLED POISONOUS fOOD-COMBINAtIONS REALLY POISONOUS?

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营养学报 2009年第2期31卷 109-113页

作者： Libin t cheng Department of Physiological Chemistry Biological Laboratory Science Society of China Nanking

the idea that to eat certain two foods simultaneously is to get poisoned has been entertained by Chinese people for many years.

关键词：有毒食物本草纲目中药解毒方法

OpenIfEM:A High Performance Modular Open-Source Software of the Immersed finite Element Method for fluid-Structure Interactions

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Computer Modeling in Engineering & Sciences 2019年第4期119卷 91-124页

作者： Jie cheng feimi Yu Lucy t.Zhang Department of Mechanical Aerospace and Nuclear Engineering Rensselaer Polytechnic InstituteTroyNY12180USA

We present a high performance modularly-built open-source *** is a C++implementation of the modified immersed finite element method(mIfEM)to solve fluid-structure interaction(fSI)*** software is modularly built to perform multiple tasks including fluid dynamics(incompressible and slightly compressible fluid models),linear and nonlinear solid mechanics,and fully coupled fluid-structure *** of open-source software packages are restricted to certain discretization methods;some are under-tested,under-documented,and lack modularity as well as *** is designed and built to include a set of generic classes for users to adapt so that any fluid and solid solvers can be coupled through the fSI *** addition,the package utilizes well-developed and tested *** also comes with standard test cases that serve as software and algorithm *** software can be built on cross-platform,i.e.,Linux,Windows,and Mac OS,using *** parallelization is also implemented for high-performance computing for large-sized *** is documented using Doxygen and publicly available to download on *** is expected to benefit the future development of fSI algorithms and be applied to a variety of fSI applications.

关键词： Immersed finite element method open-source parallelization fluid-structure interaction adaptive mesh refinement

Modeling of cable vibration effects of cable-stayed bridges

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Earthquake Engineering and Engineering Vibration 2002年第1期1卷 74-85页

作者： S.H.cheng David t.Lau Department of Civil and Environmental Engineering Carleton UniversityOttawaOntarioCanadaPost-doctoral fellow Department of Civil and Environmental Engineering Carleton UniversityOttawaOntarioCanada Professor

the analysis of dynamic responses of cable-stayed bridges subjected to wind and earthquake loads generally considers only the motions of the bridge deck and *** influence of the stay cable vibration on the responses of the bridge is either ignored or considered by approximate *** transverse vibration of the stay cables,which can be significant in some cases,are usually neglected in previous *** the present study,a new three-node cable element has been developed to model the transverse motions of the *** interactions between the cable behavior and the other parts of the bridge superstructure are considered by the concept of dynamic *** nonlinear effect of the cable caused by its self-weight is included in the *** examples are presented to demonstrate the accuracy and efficiency of the proposed model. the impact of cable vibration behavior on the dynamic characteristics of cable-stayed bridges is discussed.

关键词： cable-stayed bridges cable vibration dynamics finite elements long-span structures

A novel flexible nerve guidance conduit promotes nerve regeneration while providing excellent mechanical properties

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Neural Regeneration Research 2025年第7期20卷 2084-2094页

作者： tong Li Quhan cheng Jingai Zhang Boxin Liu Yu Shi Haoxue Wang Lijie Huang Su Zhang Ruixin Zhang Song Wang Guangxu Lu Peifu tang Zhongyang Liu Kai Wang Department of Orthopedics the Fourth Medical Center of Chinese PLA General HospitalBeijingChina Department of training and Sports Medicine Characteristic Medical Center of Chinese People’s Armed Police ForceTianjinChina Medical School of Chinese PLA BeijingChina Key Laboratory of Bioactive Materials for the Ministry of Education College of Life SciencesNankai UniversityTianjinChina Department of Orthopedics Tianjin HospitalTianjinChina Department of Rehabilitation Medicine Er Quan Hospital of PAPWuxiJiangsu ProvinceChina

Autografting is the gold standard for surgical repair of nerve defects>5 mm in length;however,autografting is associated with potential complications at the nerve donor *** an alternative,nerve guidance conduits may be *** ideal conduit should be flexible,resistant to kinks and lumen collapse,and provide physical cues to guide nerve *** designed a novel flexible conduit using electrospinning technology to create fibers on the innermost surface of the nerve guidance conduit and employed melt spinning to align ***,we prepared disordered electrospun fibers outside the aligned fibers and helical melt-spun fibers on the outer wall of the electrospun fiber *** presence of aligned fibers on the inner surface can promote the extension of nerve cells along the *** helical melt-spun fibers on the outer surface can enhance resistance to kinking and compression and provide *** novel conduit promoted nerve regeneration and functional recovery in a rat sciatic nerve defect model,suggesting that it has potential for clinical use in human nerve injuries.

关键词： aligned fibers anti-kinking helical fibers nerve guidance conduit nerve regeneration peripheral nerve injury topological guidance

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融合情感和常识知识的对话生成模型

计算机科学 2025年第1期52卷 307-314页

作者：程金凤蒋宗礼北京工业大学信息学部北京100124

随着深度学习技术的发展,开放域对话系统作为人机对话系统的重要分支也得到了快速发展。但目前开放域对话模型生成的回复语句依然存在同理心较差、多样性较低等问题。对此,提出一种融合情感和常识知识的对话生成模型。首先依据情感词典... 详细信息

随着深度学习技术的发展,开放域对话系统作为人机对话系统的重要分支也得到了快速发展。但目前开放域对话模型生成的回复语句依然存在同理心较差、多样性较低等问题。对此,提出一种融合情感和常识知识的对话生成模型。首先依据情感词典和常识知识图谱获取每个单词对应的常识知识向量,然后将该向量和单词本身的词嵌入向量一同输入编码器中进行编码,接着通过两阶段解码来生成回复语句:第一个解码阶段预测要生成单词的情感强度,并据此获得该单词对应的情感向量,第二阶段解码结合第一阶段编码的结果和已生成单词的词嵌入向量及其对应的常识知识向量作为输入,预测要生成的单词。实验结果表明,该模型生成的回复语句更具同理心和多样性,并且在PPL,BLEU,ACC和DIStINCt等指标上相比基线模型都有一定提升。

关键词：对话模型情感词典常识知识图谱两阶段解码情感强度

Quantified evaluation of particle shape effects from micro-to-macro scales for non-convex grains

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Particuology 2016年第2期14卷 23-35页

作者： Y. Yang J.f. Wang Y.M. cheng Department of Civil and Environmental Engineering The Hong Kong Polytechnic University Hong Kong China Department of Civil and Architectural Engineering City University of Hong Kong Hong Kong China

Particle shape plays an important role in both the micro and macro scales responses of a granular assem- bly. this paper presents a systematic way to interpret the shape effects of granular material during quasi-static shearing. A more suitable shape descriptor is suggested for the quantitative analysis of the macroscale strength indexes and contact parameters for non-convex grains, with special consid- eration given to the peak state and critical state. through a series of numerical simulations and related post-processing analysis, particle shape is found to directly influence the strain localisation patterns, microscale fabric distributions, microscale mobilisation indexes, and probability distribution of the nor- malised contact normal force. Additionally, the accuracy of the stress-force-fabric relationship can be influenced by the average normal force and the distribution of contact vectors. Moreover, particle shape plays a more important role than do the confining pressures in determining the friction angle. Strong force chains and the dilation effect are also found to be strongly influenced by the high confinin~ oressure.

关键词： Quantitative analysis Shape factor Statistical analysis Micro-macro indexes