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7th International Conference on MEMS, NANO and Smart Systems (ICMENS 2011)

作者： Liang Erguo Li Zifeng Yanshan Univ Qinhuangdao 066004 Peoples R China

ISBN: (纸本)9783037853122

With the combination of theoretical analysis, numerical simulation and actual test, the factors and rules impacting the collapse strength are studied. The collapse strength of the casing wear presents changes of exponent, power function, and linear trend with the residual casing wall thickness, wear radius and axial load respectively. Based on this, the computation model of collapsing strength for the whole casing wear has been established and the model is tested for verification by computing collapse strength of non-casing wear. The study results provide a guide for design of the casing sting strength and down-hole safety.

关键词： Casing wear collapsing failure collapse strength borehole bending computation model

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computation model AND INFLUENCING FACTORS ANALYSIS FOR DYNAMIC CHARACTERISTIC OF UNDERWATER MONITORING PLATFORMS

COMPUTATION MODEL AND INFLUENCING FACTORS ANALYSIS FOR DYNAM...

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3rd International Conference on Mechanical, Control, and Electronic Information (ICMCEI)

作者： He, Kongde Fang, Zifan Zhang, Yi Yang, Weihua China Three Gorges Univ Coll Mech & Power Engn Yichang 443002 Peoples R China

ISBN: (纸本)9783038351559

The computational model for underwater monitoring platform with drag force, normal lift along flow and buoyancy was formulated aimed at dynamic characteristic by the finite computing method of structure vibration modal on flow field and infinitesimal method idea, and taking into account the influence of flow force to structures dynamic characteristic. Discuss the influencing factors for natural frequency of underwater monitoring platform by numerical analysis method. Natural frequency of buoy was far from the vortex release frequency by adjusting the influencing factors. This method can effectively decrease the vibration by resonance and it has important significance to design the underwater monitoring platform.

关键词： Underwater monitoring platform Dynamic characteristic computation model Numerical simulation

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Thermal elasto-plastic computation model for a buried oil pipeline in frozen ground

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COLD REGIONS SCIENCE AND TECHNOLOGY 2010年第3期64卷 248-255页

作者： Wen, Zhi Sheng, Yu Jin, Huijin Li, Shuangyang Li, Guoyu Niu, Yonghong Chinese Acad Sci State Key Lab Frozen Soils Engn Cold & Arid Reg Environm & Engn Res Inst Lanzhou 730000 Peoples R China

The 813-mm-diameter China-Russia Crude Oil Pipeline enters northeastern China at Lianyin Mo he County Heilongjiang Province and crosses 441 km of warm discontinuous sporadic and isolated patches of permafrost and 512 km of seasonally frozen ground before reaching Darling China It is inevitable that the buried pipeline is subject to frost heave and/or thaw settlement when it passes through regions of permafrost and seasonally frozen ground with available moisture Therefore stress and deformation analyses of the pipe subject to frost action or thaw settlement are important for the safety long-term stability and economic feasibility of the buried oil pipeline system Based on the (empirical) frost heave and/or thaw settlement coefficients a simple thermal elasto-plastic finite element computation model is put forward for analyzing the stress and strain state of the pipe The influences of soil temperatures on the soil deformation were considered but those of the soil deformation on the soil temperatures were ignored in the modelling Finally two examples of the application of the computation model are presented in which the stress and deformation of a pipe exposed to frost heave or thaw settlement is calculated The results of the frost action computation show that the effective stress on the pipe increases linearly with the frost heave deformation The largest pipe deformations and stresses may occur when crossing frost mounds due to differential frost heaving The stress and deformation smooth out from the frost mound The results of thaw settlement computation show that the pipe stress changes greatly near the interface of thaw settlement zone and no thaw settlement zone and the thaw settlement has small effect on the stability of oil pipeline The computation results show that the oil pipeline design in the permafrost regions should pay more attention on frost heave hazard than thaw settlement hazard (C) 2010 Elsevier BV All rights reserved

关键词： Frozen ground Pipeline Frost heave Thaw settlement Thermal elasto plastic computation model

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Ground view factor computation model for bifacial photovoltaic collector field: uniform and non-uniform surfaces

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ENERGY REPORTS 2021年 7卷 9133-9149页

作者： Alam, Marzia Gul, Mehreen Saleem Muneer, Tariq Heriot Watt Univ Sch Energy Geosci Infrastruct & Soc EGIS Riccarton Campus Edinburgh EH14 4AS Midlothian Scotland Edinburgh Napier Univ Sch Engn & Built Environm 10 Colinton Rd Edinburgh EH10 5DT Midlothian Scotland

The photovoltaic collectors in a field are subject to three types of solar radiation: direct, diffuse, and reflected irradiance. The reflected irradiance received by solar photovoltaic (PV) depends on the view factor from solar PV to the ground. This view factor component is dominant for bifacial PV due to additional reflected irradiance gain, which can be achieved from the module's rear side. This paper proposes and verifies a finite element method based view factor computation model, which can handle both uniform and non-uniform ground surfaces. The unique contribution of this work is that it introduces a geometric progression based finite element mesh generation process that forms the quasi-uniform grid. The generated grid values are fitted into the computation model to calculate the view factor from bifacial photovoltaics to the ground, known as the ground view factor (GVF). The proposed computation model can achieve an accuracy of 99%. To keep accuracy at this level, the smallest element size of the coarse mesh should be within 0.1%-0.4% of surface width or length. Moreover, the geometric progression ratio of the fine and coarse mesh should be in the range of 1.001-1.002 and 1.01-1.04, respectively. The model is analysed under six different PV field variables: multiple reflective ground surfaces, the height of PV, tilted ground surface, PV position in the ground, length and width of the ground, and PV string length. For the different string sizes considered here, the view factor model's computation time varies from 180 s to 257 min for the iteration size of 7.67 billion to 765 billion. The view factor computation model will contribute to analyse reflected irradiance at the rear side of bifacial PV, which is essential to predict the energy generation accurately. The proposed model is also beneficial for urban planning and addressing heat gain of the building-integrated PV system and energy usage. (C) 2021 The Authors. Published by Elsevier Ltd.

关键词： Bifacial photovoltaic Geometric progression computation model Finite element method Non-uniform ground Ground view factor

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An improved computation model for critical bending force of three-jaw chucks

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JOURNAL OF MATERIALS PROCESSING TECHNOLOGY 2008年第1-3期208卷 124-129页

作者： Feng, P. F. Wu, Z. J. Yu, D. W. Uhlmann, E. Tsinghua Univ Dept Precis Instruments & Mechanol Beijing 100084 Peoples R China Tech Univ Berlin Inst Machine Tools & Factory Management D-10587 Berlin Germany

Because of its automatic centering capability, and its high flexibility with respect to different clamping diameters, the three-jaw chuck is the preferred clamping device for turning operations. However, because of insufficient modelling methods, the existing approaches for determining the required clamping force of jaw-chucks lead to unreliable and inconsistent computation results. This is especially true for the crucial computation of critical bending force. An improved analytic computation model for determining the critical bending force of three-jaw chucks is introduced in this article, and verified through experimental investigations. Finite element analysis-based knowledge about both the pressure distribution on clamping surfaces, and workpiece stiffness behaviour, ensures a safe and exact computation of the critical bending force and the critical bending moment. This exact computation makes it possible to utilize the potential of jaw-chucks at higher rotational speeds and guarantees safe workpiece clamping. (C) 2008 Elsevier B.V. All rights reserved.

关键词： Three-jaw chuck Critical bending force computation model Workpiece stiffness

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Rapid computation model for accurate evaluation of electromagnetic interference shielding effectiveness of fabric with hole based on equivalent coefficient

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INTERNATIONAL JOURNAL OF APPLIED ELECTROMAGNETICS AND MECHANICS 2015年第1期47卷 177-185页

作者： Wang, Xiuchen Liu, Zhe Zhou, Zhong Zhongyuan Univ Technol Zhengzhou 450007 Henan Peoples R China

Though electromagnetic interference (EMI) shielding fabric with rectangular hole has wide application in various fields, there is not a mature approach to calculate its shielding effectiveness (SE) at present. This paper constructs a rapid computation model of the SE of the EMI shielding fabric with hole based on equivalent coefficient. Firstly, the rectangular hole characteristic is analyzed and a structure model of the rectangular hole under the consideration of the hole edge characteristic is described. The equivalent relationship between the fabric hole and the standard hole is presented according to the equivalent theory. The rapid computation model of the SE of the EMI shielding fabric with hole is built including the equivalent coefficient and transmission coefficient according to the EMI shielding theory and the method to determine the equivalent coefficient is also given. Finally, the computation model is verified by experiments. The results show that the accuracy and the computational efficiency of the proposed model are good, and the model can be applied to the fabrics with wide weaves and various rectangular hole sizes.

关键词： Hole electromagnetic interference shielding fabric shielding effectiveness computation model

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H-BSP: A hierarchical BSP computation model

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JOURNAL OF SUPERCOMPUTING 2001年第2期18卷 179-200页

作者： Cha, HJ Lee, D Kwangwoon Univ Dept Comp Sci Seoul 139701 South Korea

This paper presents a new parallel computing model, called H-BSP, which adds a hierarchical concept to the BSP(Bulk Synchronous Parallel) computing model. An H-BSP program consists of a number of BSP groups which are dynamically created at run time and executed in a hierarchical fashion. H-BSP allows algorithm designers to develop more efficient algorithms by utilizing processor locality in the program. Based on the distributed memory model, H-BSP provides a group-based programming paradigm and supports Divide & Conquer algorithms efficiently. This paper describes the structure of the H-BSP model, complexity analysis and some examples of H-BSP algorithm. Also presented is the performance characteristics of H-BSP algorithms based on the simulation analysis. Simulation results show that H-BSP takes advantages of processor locality and performs well in low bandwidth networks or in a constant-valence architecture such as 2-dimensional mesh. It is also proved that H-BSP can predict algorithm performance better than BSP, due to its locality-preserving nature.

关键词： computation model BSP processor locality scalable computing analysis

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A Parallel Interval computation model for Global Optimization with Automatic Load Balancing

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Journal of Computer Science & Technology 2012年第4期27卷 744-753页

作者：吴勇 Arun Kumar Department of International Business and Asian Studies Griffith University School of Aerospace Mechanical and Manufacturing EngineeringRMIT University

In this paper, we propose a decentralized parallel computation model for global optimization using interval analysis. The model is adaptive to any number of processors and the workload is automatically and evenly distributed among all processors by alternative message passing. The problems received by each processor are processed based on their local dominance properties, which avoids unnecessary interval evaluations. Further, the problem is treated as a whole at the beginning of computation so that no initial decomposition scheme is required. Numerical experiments indicate that the model works well and is stable with different number of parallel processors, distributes the load evenly among the processors, and provides an impressive speedup, especially when the problem is time-consuming to solve.

关键词： parallel processing automatic load balancing computation model interval analysis global optimization

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Machine learning model-based two-dimensional matrix computation model for human motion and dance recovery

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COMPLEX & INTELLIGENT SYSTEMS 2021年第4期7卷 1805-1815页

作者： Zhang, Yi Zhang, Mengni Hubei Univ Sci & Technol Coll Mus Xianning 450046 Peoples R China

Many regions of human movement capturing are commonly used. Still, it includes a complicated capturing method, and the obtained information contains missing information invariably due to the human's body or clothing structure. Recovery of motion that aims to recover from degraded observation and the underlying complete sequence of motion is still a difficult task, because the nonlinear structure and the filming property is integrated into the movements. Machine learning model based two-dimensional matrix computation (MM-TDMC) approach demonstrates promising performance in short-term motion recovery problems. However, the theoretical guarantee for the recovery of nonlinear movement information lacks in the two-dimensional matrix computation model developed for linear information. To overcome this drawback, this study proposes MM-TDMC for human motion and dance recovery. The advantages of the machine learning-based Two-dimensional matrix computation model for human motion and dance recovery shows extensive experimental results and comparisons with auto-conditioned recurrent neural network, multimodal corpus, low-rank matrix completion, and kinect sensors methods.

关键词： computation model Machine learning Human motion Two-dimensional matrix Neural

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A computation model OF PARALLEL SOLUTION OF LINEAR-EQUATIONS

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IEEE TRANSACTIONS ON COMPUTERS 1980年第7期29卷 632-638页

作者： WING, O HUANG, JW IBM CORP THOMAS J WATSON RES CTRYORKTOWN HTSNY 10598

The solution process of Ax = b is modeled by an acyclic directed graph in which the nodes represent the arithmetic operations applied to the elements of A, and the arcs represent the precedence relations that exist among the operations in the solution process. Operations that can be done in parallel are identified in the model and the absolute minimum completion time and lower bounds on the minimum number of processors required to solve the equations in minimal time can be found from it. Properties of the model are derived. Hu"s level scheduling strategy is applied to examples of sparse matrix equations with surprisingly good results. Speed-up using parallel processing is found to be proportional to the number of processors when it is 10-20 percent of the order of A.

关键词： computation model parallel computation parallel processing parallel solution of linear equations

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