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Truncation error calculation based on Richardson extrapolation for variable-step collaborative simulation

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Science china(Information Sciences) 2011年第6期54卷 1238-1250页

作者： zhang heming 1 , liang silu 2., SONG ShiJi 1 & WANG HongWei 3 1 Department of Automation,{2., tsinghua university, beijing 100084, china 2.Computer and Information Management Center, tsinghua university beijing 100084, china 3 Engineering Design Centre, Engineering Department, Cambridge university, Cambridge CB2.1PZ, UK 1. Department of Automation TNList Tsinghua University Beijing 100084 China2. Computer and Information Management Center Tsinghua University Beijing 100084 China3. Engineering Design Centre Engineering Department Cambridge University Cambridge CB2 1PZ UK

Collaborative simulation is an effective approach to performing simulation analysis for complex systems by integrating models developed for different engineering disciplines. Collaborative simulation issues include the modeling of coupled multidisciplinary systems, and the simulation running time integration of these models that are solved parallelly. Estimation of the local truncation error of coupling models is the key to solve multidisciplinary collaborative simulation problem, which is actually used to restrict the simulation step. This paper presents a variable-step method based on Richardson extrapolation for calculating the local truncation error to solve collaborative simulation problem of multidisciplinary coupling models. Formulas for estimating the local truncation error are derived through theoretical analysis by using integration methods and interpolation technologies, respectively. The simulation experiments are illustrated to validate the accuracy and efficiency of proposed collaborative simulation algorithm in comparison with the usual combinative algorithm.

关键词： multidisciplinary systems collaborative simulation variable-step algorithm error estimation

Fiber optic monitoring of an anti-slide pile in a retrogressive landslide

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 333-343页

作者： Lei zhang Honghu Zhu heming Han Bin Shi School of Water Resources and Environment China University of GeosciencesBeijing100084China State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijing100084China School of Earth Sciences and Engineering Nanjing UniversityNanjing210023China School of Civil and Environmental Engineering Nanyang Technological University639798Singapore

Anti-slide piles are one of the most important reinforcement structures against landslides,and evalu-ating the working conditions is of great significance for landslide *** widely adopted analytical methods of pile internal forces include cantilever beam method and elastic foundation beam ***,due to many assumptions involved in calculation,the analytical models cannot be fully applicable to complex site situations,*** with multi-sliding surfaces and pile-soil interface separation as discussed *** view of this,the combination of distributed fiber optic sensing(DFOS)and strain-internal force conversion methods was proposed to evaluate the working conditions of an anti-sliding pile in a typical retrogressive landslide in the Three Gorges reservoir area,*** optical time domain reflectometry(BOTDR)was utilized to monitor the strain distri-bution along the ***,by analyzing the relative deformation between the pile and its adjacent inclinometer,the pile-soil interface separation was ***,the internal forces of the anti-slide pile were derived based on the strain-internal force conversion *** to the ratio of calculated internal forces to the design values,the working conditions of the anti-slide pile could be *** results demonstrated that the proposed method could reveal the deformation pattern of the anti-slide pile system,and can quantitatively evaluate its working conditions.

关键词： Anti-slide pile Multi-sliding surface Pile-soil interface Brillouin optical time domain reflectometry (BOTDR) Geotechnical monitoring Reservoir landslide

In-situ construction of abundant active centers on hierarchically porous carbon electrode toward high-performance phosphate electrosorption: Synergistic effect of electric field and capture sites

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Green Energy & Environment 2024年第1期9卷 126-137页

作者： Peng zhang Fukuan Li Mingming He silu Huo Xueli zhang Benqiang Cen Dezhi Fang Kexun Li Hao Wang College of Environmental Science and Engineering Nankai UniversityTianjin300350China MOE Key Laboratory of Pollution Processes and Environmental Criteria Tianjin Key Laboratory of Environmental Remediation and Pollution ControlTianjin Key Laboratory of Environmental Technology for Complex Trans-Media PollutionNankai UniversityTianjin300350China State Key Laboratory of Simulation and Regulation of Water Cycles in River Basins China Institute of Water Resources and Hydropower ResearchBeijing100038China

Phosphate removal is crucial for eutrophication control and water quality ***-assisted adsorption,an eco-friendly elec-trosorption process,exhibited a promising potential for wastewater ***,there are few works focused on phosphate electro-sorption,and reported electrodes cannot attach satisfactory removal capacities and ***,electro-assisted adsorption of phosphate via in-situ construction of La active centers on hierarchically porous carbon(LaPC)has been originally *** resulted LaPC composite not only possessed a hierarchically porous structure with uniformly dispersed La active sites,but also provided good conductivity for interfacial electron *** LaPC electrode achieved an ultrahigh phosphate electrosorption capability of 462.01 mg g^(-1) at 1 V,outperforming most existing *** superior phosphate removal performance originates from abundant active centers formed by the coupling of electricﬁeld and capture ***,the stability and selectivity toward phosphate capture were maintained well even under comprehensive ***,a series of kinetics and isotherms models were employed to validate the electrosorption *** work demonstrates a deep understanding and promotes a new level of phosphate electrosorption.

关键词： Electro-assisted adsorption Electrosorption Phosphate removal Active centers MOF-derived carbon

Systematic investigation of nucleon optical model potentials in(p,d)transfer reactions

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Chinese Physics C 2024年第7期48卷 168-175页

作者：陈思璐刘子旋张智续瑞瑞庞丹阳许祎萍 School of Nuclear Science and Engineering North China Electric Power UniversityBeijing 102206China china Nuclear Data Center China Institute of Atomic EnergyBeijing 102413China School of Physics Beihang UniversityBeijing 100191China

The consistent three-body model reaction methodology(TBMRM)proposed by *** et al.[***.C 69,064313(2.04);***.C 73,044608(2.06);***.C 75,06432.(2.07)],which includes adopting the simple zero-range adiabatic wave approximation,constraining the single-particle potentials using modern Hartree-Fock calculations,and using global nucleon optical model potential(OMP)geometries,are widely applied in systematic studies of transfer *** this study,we investigate the influence of different nucleon OMPs in extracting spectroscopic factors(SFs)from(p,d)*** study covers 32.sets of angular distribution data of(p,d)reactions on four targets and a large range of incident energies(2.-2.0 MeV/nucleon).This study uses two semi-microscopic nucleon OMPs,i.e.,Jeukenne,Lejeune,and Mahaux(JLM)[***.C 16,80(1977);***.C 58,1118(1998)]and CTOM[***.C 94,034606(2.16)],and a pure microscopic nucleon potential,i.e.,WLH[***.12.,182.02.2.2.)].The results are compared with those using the phenomenological global optical potential KD02.***.A 713,2.1(2.03)].We find that the incident energy dependence of spectroscopic factors extracted from(p,d)reactions is evidently suppressed when microscopic OMPs are employed for ^(12.C,^(2.)Si,and *** addition,spectroscopic factors extracted using the systematic microscopic optical potential CTOM based on the Dirac-Brueckner-Hartree-Fock theory are more in line with the results obtained from(e,e′p)measurements,except for 16O and ^(40)Ca at high energies(>100 MeV),necessitating an exact treatment of double-magic *** results obtained by using the pure microscopic optical potential,WLH,based on the EFT theory show the same trend as those of CTOM but are generally *** JLM potential,which relies on simplified nuclear matter calculations with old-fashioned bare interactions,produces results that are very similar to those of the phenomenological potential *** results indicate that modern

关键词： optical model potentials transfer reactions spectroscopic factors

Integrating Polymorphic PDMs

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Computer Aided Drafting,Design and Manufacturing 1998年第2期8卷 50-56页

作者： Li Yinsheng Tong Bingshu zhang heming Huang Hongxing ({2. university, beijing, 100084)

Along with the explosive increase of product data management systems (PDMs),integrating polymorphic PDMs is becoming one of the focuses in the field. Aner brief describing several features of PDM, and market requirements and required performance for integrating the polymorphic PDMs, the paper specializes in discussing some key technologies involved in virtual enterprise oriented integrated development. Some implementing strategies and procedures are proposed.

关键词： Product Data Management (PDM) Virtual Enterprise (VE) Product Structure Model,Process Model Web Server

Combinative Algorithms for the Multidisciplinary Collaborative Simulation of Complex Mechatronic Products Based on Major Step and Convergent Integration Step

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Chinese Journal of Mechanical Engineering 2011年第3期24卷 355-363页

作者： liang silue {2. heming WANG Hongwei National CIMSEngineeringResearch Center Tsinghua University Beijing 100084 China Computer and Information Management Center Tsinghua University Beijing 100084 China Engineering Design Centre University of Cambridge Cambridge CB2 1PZ UK

Multidisciplinary collaborative simulation （MCS） is an important area of research in the domain of multidisciplinary design optimization （MDO）.Although previous research for MCS has to some extent addressed some issues like using of multiple tools,integration stability,control of step size,data synchronization,etc,further work is still necessary to study how to achieve improved precision.A theoretical model is formulated to describe and analyze the integration process of MCS.A basic algorithm with equal major steps is proposed based on the model,along with two methods of implementation for the model,namely the serial method and the parallel method.A further algorithm based on convergent integration step is proposed,which has a more flexible strategy for run-time *** influence of interpolation techniques on simulation performance is studied as *** of the performance of various algorithms with different interpolation techniques are performed for both a simple numerical example and a complex mechatronic *** novel algorithm based on convergent integration step,when used with a high-order interpolation technique,has better performance in terms of precision and *** innovation of this paper is mainly on the validation of high precision of the proposed convergent integration step algorithm.

关键词： mechatronic product multidisciplinary collaborative simulation multi-rate integration convergent integration step

Distribution characteristics and petroleum geological significance of the silurian asphaltic sandstones in Tarim Basin

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Science china Earth Sciences 2004年第Z2期47卷 199-208页

作者： zhang Jun1,2. PANG Xiongqi1,2. LIU Luofu1,2. JIANG Zhenxue1,2.& LIU Yunhong3 1. Basin and Reservoir Research Center, university of Petroleum, {2. 102.49, china 2. Key Laboratory for Hydrocarbon Accumulation Mechanism of the Ministry of Education, university of Petroleum, {2. 102.49, china 3. Korla Research Institute of Geophysics, Bureau of Geophysics Prospecting, Korla 841000, china Basin and Reservoir Research Center University of Petroleum Beijing 102249 China Key Laboratory for Hydrocarbon Accumulation Mechanism of the Ministry of Education University of Petroleum Beijing 102249 China Korla Research Institute of Geophysics Bureau of Geophysics Prospecting Korla 841000 China

The Tarim Basin is a typical superimposed basin in which there have occurred mul-tiphase adjustment and destruction of the reservoirs. The widely distributed asphaltic sandstones of the silurian are the very product after destruction of the reservoirs. Studies show that the silu-rian asphaltic sandstones distributed in both the middle and western parts on the basin are con-trolled chiefly by the Caledonian oil source area and by the Tazhong, Tabei and Bachu uplifts, whereas the distribution of the asphaltic sandstones on local structural belts is controlled by the reservoirs sedimentary system. Vertically, most of the asphaltic sandstones are under the re-gional caprock of red mudstones and the upper sandstone section of compact lithology. Due to the difference of hydrocarbon destruction in the early stage and the influence of hydrocarbon recharge in the late stage, the asphaltic sandstones and oil-bearing sandstones in the Tazhong area can be vertically divided into the upper and lower sections and they have an interactive distribution relationship as well. Asphaltic sandstones exist not only in intergranular pores but also inside the grains of sand and between the crevices, proving the destruction of early reser-voirs due to uplifting. The existence of asphaltic sandstones over a large area reveals that the large-scale migration and accumulation and the subsequent destruction of hydrocarbons in the Craton area. The destruction caused a loss of the reserve resources of the Palaeozoic amount-ing to nearly 13.3 billion tons. Asphaltic sandstones formed after the destruction of oil and gas may serve as an effective caprock which is beneficial to accumulation of hydrocarbons and for-mation of the pool sealed by asphaltic sandstones in the later stage. The destruction of the early silurian hydrocarbons depends on the stratigraphic burial depth. The deep part under the north-ern slope of Tazhong is an area favorable to search of undestroyed silurian oil reservoirs.

关键词： Tarim Basin, asphaltic sandstone, silurian, hydrocarbon destruction, distribution characteristics, reserve of resources.

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农田环境下无人机图像并行拼接识别算法

农业工程学报 2024年第9期40卷 154-163页

作者：许鑫张力岳继博钟鹤鸣王颖刘杰乔红波河南农业大学信息与管理科学学院郑州450002 全国农业推广技术服务中心北京100125

为改善在农田环境下无人机图像计算速度和效率,该研究提出了一种农田环境下无人机图像并行拼接识别算法。利用倒二叉树并行拼接识别算法,通过提取图像拼接中的变换矩阵,实现拼接识别同时进行。根据边缘设备的CPU核心数和图像数量自动将... 详细信息

为改善在农田环境下无人机图像计算速度和效率,该研究提出了一种农田环境下无人机图像并行拼接识别算法。利用倒二叉树并行拼接识别算法,通过提取图像拼接中的变换矩阵,实现拼接识别同时进行。根据边缘设备的CPU核心数和图像数量自动将图像拼接识别任务划分为多个子进程,并分配到不同核心上执行,以提高在农田环境下的计算效率。试验结果表明:相同试验环境和数据集条件下,倒二叉树并行拼接算法的拼接耗时相较于其他算法平均减少了60%~90%左右;在农田环境下,倒二叉树并行拼接识别相较于串行拼接识别的耗时减少了70%,图像识别的平均像素交并比提升了10.17个百分点,说明在农田环境下采用多线程倒二叉树并行算法可以更好地利用农田环境下边缘设备的计算资源,大幅提升无人机图像的拼接和识别的速度,为无人机的快速实时监测提供技术支撑。

关键词：无人机遥感图像处理全景拼接多核CPU 多进程

A solution of multidisciplinary collaborative simulation for complex engineering systems in a distributed heterogeneous environment

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Science in china(Series F) 2009年第10期52卷 1848-1862页

作者： zhang heming CIMS-ERC Department of Automation TNList Tsinghua University Beijing 100084 China

This paper presents an integrated approach to multidisciplinary collaborative simulation for complex engineering systems. The formulized paradigm of multidisciplinary collaborative simulation for com- plex engineering systems is principally analyzed. An IEEE HLA and web services based framework is proposed to provide a heterogeneous, distributed and collaborative running environment where multidisciplinary modeling, running management and post-processing of collaborative simulation are undertaken. The mechanism of multidisciplinary collaborative modeling, disciplinary model transformation, and time-synchronized simulation advancement are studied in detail. A prototype with the functions of multidisciplinary modeling, running management and post-processing for collaborative simulations is developed, and a typical complex engineering system is chosen as a case study to demonstrate the effectiveness of this new approach towards collaborative simulation.

关键词： multidisciplinary modeling distributed collaborative simulation HLA web services complex engineering system