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PREDECESSOR-SET TECHNIQUE FOR RELIABILITY EVALUATION OF A STOCHASTIC MANUFACTURING SYSTEM

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Journal of Systems Science and Systems Engineering 2015年第2期24卷 190-210页

作者： yi-Kuei Lin ping-Chen Chang Department of Industrial Management National Taiwan University of Science & Technology

This paper studies the reliability evaluation of a stochastic manufacturing system with multiple production lines in parallel. Multiple repairs and different failure rates, never simultaneously addressed in earlier works, are taken into account. First, a revised graphical methodology integrating transformation and decomposition is utilized to construct the stochastic manufacturing system as a multi-state manufacturing network （MSMN）. In particular, a ＂predecessor-set＂ technique is proposed to deal with multiple repairs. An algorithm is proposed to generate the lowest capacity vectors （LCVs） that stations should provide to satisfy the workloads. Subsequently, the system reliability of the MSMN, which is defined as the probability of demand satisfaction, is calculated in terms of the LCVs. A real case of a printed circuit board manufacturing system is utilized to demonstrate how the system reliability can be evaluated. A further decision making issue is addressed based on the derived system reliability.

关键词： Multi-state manufacturing network (MSMN) predecessor-set lowest capacity vector(LCV) different failure rates multiple repairs system reliability

Validation and application of three-dimensional discontinuous deformation analysis with tetrahedron finite element meshed block

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Acta Mechanica Sinica 2012年第6期28卷 1602-1616页

作者： Jun Liu Zheng Nan ping yi School of Hydraulic Engineering Dalian University of Technology School of Civil Engineering Dalian University of Technology

In the last decade, three dimensional discontin- uous deformation analyses （3D DDA） has attracted more and more attention of researchers and geotechnical engineers worldwide. The original DDA formulation utilizes a linear displacement function to describe the block movement and deformation, which would cause block expansion under rigid body rotation and thus limit its capability to model block de- formation. In this paper, 3D DDA is coupled with tetrahe- dron finite elements to tackle these two problems. Tetrahe- dron is the simplest in the 3D domain and makes it easy to implement automatic discretization, even for complex topol- ogy shape. Furthermore, element faces will remain planar and element edges will remain straight after deformation for tetrahedron finite elements and polyhedral contact detection schemes can be used directly. The matrices of equilibrium equations for this coupled method are given in detail and an effective contact searching algorithm is suggested. Valida- tion is conducted by comparing the results of the proposed coupled method with that of physical model tests using one of the most common failure modes, i.e., wedge failure. Most of the failure modes predicted by the coupled method agree with the physical model results except for 4 cases out of the total 65 cases. Finally, a complex rockslide example demon- strates the robustness and versatility of the coupled method.

关键词： Three-dimensional discontinuous deformation analysis Finite element method Coupled method Valida-tion

Kinetic modeling the effects of primary migration, diffusion and waterwashing on Upper Paleozoic coal-derived gas at the center of Ordos Basin

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Chinese Science Bulletin 2004年第S1期49卷 94-100页

作者： SHUAI Yanhua zou Yanrong PENG ping’an State Key Laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

Gold reactor pyrolysis system is used to model the gas formation from the Upper Paleozoic coal measures and the results show coal-derived gas characterized with δ13C1 of-33.46‰, δ13C2 of-23.1‰, dryness(C1/C1-4) 85.6%. And then, effects of the post-genetic processes on coal- derived gas are analyzed in turn: (i) About 27% coal-derived gases constituted with more methane are calculated to be lost during diffusion. The residual in reservoir are characterized with almost the same compositions as the original, which suggests faint influence by diffusion (the residual, δ13C1 of -32.78‰, δ13C2 of-23.1‰, C1/C1-4 83%); (ii) Water washing made about 8% coal-formed gases lost and their components and stable carbon isotopes are stable; (iii) In the final, it is speculated that primary migration makes much more wet gas (C2-4) leave in coal measures. The variance of gas dryness induced by this factor is estimated to be about 10%.

关键词： diffusion migration dryness isotopic ratios Ordos Basin Upper Paleozoic coal.

Collaborative visual SLAM for multiple agents:A brief survey

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Virtual Reality & Intelligent Hardware 2019年第5期1卷 461-482页

作者： Danping zou ping TAN Wenxian YU Shanghai Key Laboratory of Navigation and Location-Based Services Shanghai Key Laboratory of Intelligent Sensing and RecognitionShanghai Jiao Tong UniversityShanghai 200240China School of Computing Science Simon Fraser UniversityBurnaby V5A 1S6Canada

This article presents a brief survey to visual simultaneous localization and mapping (SLAM) systems applied to multiple independently moving agents, such as a team of ground or aerial vehicles, a group of users holding augmented or virtual reality devices. Such visual SLAM system, name as collaborative visual SLAM, is different from a typical visual SLAM deployed on a single agent in that information is exchanged or shared among different agents to achieve better robustness, efficiency, and accuracy. We review the representative works on this topic proposed in the past ten years and describe the key components involved in designing such a system including collaborative pose estimation and mapping tasks, as well as the emerging topic of decentralized architecture. We believe this brief survey could be helpful to someone who are working on this topic or developing multi-agent applications, particularly micro-aerial vehicle swarm or collaborative augmented/virtual reality.

关键词： Visual SLAM Multiple agent UAV swarm Collaborative AR/VR

A unified model for determining fracture strain of metal films on flexible substrates

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Journal of Materials Science & Technology 2020年第19期54卷 87-94页

作者： Xu-ping Wu Xue-Mei Luo Hong-Lei Chen Ji-Peng zou Guang-ping Zhang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of Chin1Shenyang 110016China

Failure strain determination of polymer-supported thin films is a key for the design of the flexible devices.A theoretical model R/R0=(L/L0)2(R,L are the electrical resistance and the length of the stretched film,respectively.R0,L0 are the corresponding initial values.)has been widely used to determine the fracture strain of thin films on flexible ***,this equation loses its function in some special ***,a simple and universal theoretical model was proposed to determine the fracture strain of metal thin films on flexible substrates in more generally *** this model,we investigated the thicknessdependent failure strains of Cu-5 at.%Al films with thickness of 10 nm,200 nm,1000 nm,and Ti films with thickness of 50 nm,100 nm,300 *** model was also employed to study the published data *** results showed that the new model provided a fairly good prediction of the failure strains of different films.

关键词： Thin films Fracture Electrical resistance Microstructure Flexible substrate

Experimental research on unstable movements of sandbars under wave actions

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Water Science and Engineering 2012年第2期5卷 175-190页

作者： Jing yiN Zhi-li zou ping DONG Hai-fei ZHANG Guo-qiang WU yi-nan PAN State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 R R. China Department of Civil Engineering School of Engineering University of Dundee Dundee DD1 4HN UK

This study is motivated by recognition of complex sandbar evolution patterns under wave actions inside the surf zone. A series of physical model experiments were conducted in a wave flume to investigate sandbar migration under various wave conditions, including wave groups, regular waves, and random waves. It was observed that under certain wave conditions sandbars move alternately shoreward and seaward rather than continuously in the same direction. The measurements show that the unstable movement of sandbars is closely related to the amplitude modulation of waves. Smaller amplitude modulation tends to produce more intense unstable bar movements. Data analysis further shows that the sandbar migration does not seem to be a passive response of the sea bed to wave forcing, but is most likely caused by the feedback interaction between waves and bed topography.

关键词： unstable movement of sandbar sediment transport forced response wave action

Subcarrier and power allocation algorithm based on inter-cell interference mitigation for OFDMA system

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The Journal of China Universities of Posts and Telecommunications 2007年第1期14卷 90-95页

作者： zou Ting DENG Gang WANG ying ZHANG ping Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications. Beijing 100876 China

This article proposes a dynamic subcarrier and power allocation algorithm for multicell orthogonal frequency division multiple access （OFDMA） downlink system, based on inter-cell interference （ICI） mitigation. Different from other ICI mitigation schemes, which pay little attention to power allocation in the system, the proposed algorithm assigns channels to each user, based on proportional-fair （PF） scheduling and ICI coordination, whereas allocating power is based on link gain distribution and the loading bit based on adaptive modulation and coding （AMC） in base transceiver station （BTS）. Simulation results show that the algorithm yields better performance for data services under fast fading.

关键词： ICI mitigation OFDMA cell edge user equipments(CEUs) cell centre user equipments (CCUs) dynamic resource allocation

Entropy method for determination of weight of evaluating indicators in fuzzy synthetic evaluation for water quality assessment

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Journal of Environmental Sciences 2006年第5期18卷 1020-1023页

作者： zou Zhi-hong YUN yi SUN Jing-nan School of Economics and Management Beihang University Beijing 100083 China

Considering the difficulty of fuzzy synthetic evaluation method in calculation of the multiple factors and ignorance of the relationship among evaluating objects, a new weight evaluation process using entropy method was introduced. This improved method for determination of weight of the evaluating indicators was applied in water quality assessment of the Three Gorges reservoir area. The results showed that this method was favorable for fuzzy synthetic evaluation when there were more than one evaluating objects. One calculation was enough for calculating every monitoring point. Compared with the original evaluation method, the method predigested the fuzzy synthetic evaluation process greatly and the evaluation results are more reasonable.

关键词： water quality evaluation fuzzy weight of evaluating indicator entropy method

A likely role for a novel PH-domain containing protein,PEPP2,in connecting membrane and cytoskeleton

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BIOCELL 2012年第3期36卷 127-132页

作者： yi zou WENping ZHONG Department of Biology School of Life Science and TechnologyJinan UniversityGuangzhouChina

PH domains(pleckstrin homology)are well known to bind membrane phosphoinositides with different specificities and direct PH domain-containing proteins to discrete subcellular apartments with assistances of alternative binding *** domain-containing proteins are found to be involved in a wide range of cellular events,including signalling,cytoskeleton rearrangement and vesicular *** we showed that a novel PH domain-containing protein,PEPP2,displayed moderate phosphoinositide binding *** length PEPP2 associated with both plasma membrane and *** membrane-associated PEPP2 nucleated at cell-cell contacts and the leading edge of migrating *** of PEPP2 increased membrane microviscosity,indicating a potential role of PEPP2 in regulating function of membrane and microtubules.

关键词： microtubule membrane phosphoinositide microviscosity wortmannin