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Macro modeling and analysis of traffic flow with road width 被引量:4
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作者 唐铁桥 李传耀 +1 位作者 黄海军 尚华艳 《Journal of Central South University》 SCIE EI CAS 2011年第5期1757-1764,共8页
The macro modeling and the solution of traffic flow with road width were investigated.Firstly,a new macro model with the consideration of road width was proposed.Secondly,the effects of road width on uniform flow and ... The macro modeling and the solution of traffic flow with road width were investigated.Firstly,a new macro model with the consideration of road width was proposed.Secondly,the effects of road width on uniform flow and small perturbation were studied.The analytical and numerical results show that widening (shrinking) road can enhance (reduce) the equilibrium speed and flow,and the increments (decrements) will increase with the absolute value of road width gradient.In addition,the numerical results illustrate that the new model can describe the effects of road width on the evolutions of uniform flow and small perturbation. 展开更多
关键词 traffic flow road width macro modeling PERTURBATION
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Behavior of reinforced concrete structural walls with various opening locations: experiments and macro model 被引量:1
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作者 Ji-yang WANG Masanobu SAKASHITA +2 位作者 Susumu KONO Hitoshi TANAKA Wen-juan LOU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2010年第3期202-211,共10页
Two experimental tests of three-storied reinforced concrete structural walls having large openings were performed.Based on an original macro model,a multiple modified macro-model was proposed to develop a simple metho... Two experimental tests of three-storied reinforced concrete structural walls having large openings were performed.Based on an original macro model,a multiple modified macro-model was proposed to develop a simple method to design a reinforced concrete structural wall with large openings and various opening locations.The interaction between reinforcement ties and concrete struts formed along the perimeter of openings was neglected in the original model.However,the strut-and-tie node was proposed to take account of such interaction in the proposed model.The predicted behavior of two specimens using such a proposed model was compared with the experimental results.It is shown that the behavior of structural walls with large openings could be modeled well using the proposed model.Moreover,the study indicates that the proposed model is applicable even in cases of multi-story structural walls having large openings and various opening locations. 展开更多
关键词 Structural wall Shear behavior Multiple modified macro model Various opening locations Opening ratio
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A macro model of spin-transfer torque magnetic tunnel junction
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作者 Ming-Bo Chen Kun-Kun Li +5 位作者 Xiao-Lei Yang Xue Peng Wang-Da Li En-Long Liu Hui-Zhen Wu Shi-Kun He 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第12期476-481,共6页
The precise compact modeling of magnetic devices is pivotal for the integrated design of spin-transfer torque magnetic tunnel junction(STT-MTJ)in conjunction with CMOS circuitry.This work presents a macro model for an... The precise compact modeling of magnetic devices is pivotal for the integrated design of spin-transfer torque magnetic tunnel junction(STT-MTJ)in conjunction with CMOS circuitry.This work presents a macro model for an STT-MTJ which is compatible with SPICE simulation platforms.The model accurately replicates the electrical performance of the MTJ,encompassing the resistance-voltage characteristics and the pulse-width-dependent state switching behavior,and is validated with various experimental data.Additionally,the impact of process variations,particularly those affecting the MTJ diameter and barrier thickness is investigated and summarized in a corner model.Monte Carlo simulations demonstrate that our adaptable and streamlined model can be efficiently incorporated into the design of integrated circuits. 展开更多
关键词 STT-MTJ macro model process corner Monte Carlo simulation
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Macro Model Study for Nonlinear Spring of Tense Torsion Bar in Gap-Closing Type Electrostatic Micromirror
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作者 Gyu II Shim Ryoichi Mimoto Shinya Kumagai Minoru Sasaki 《Journal of Mechanics Engineering and Automation》 2012年第7期446-454,共9页
Nonlinear spring characteristics of the tense torsion bar in the gap-closing type electrostatic micromirror are examined. The macro model is introduced for the experimental study. The tension applied in the torsion ba... Nonlinear spring characteristics of the tense torsion bar in the gap-closing type electrostatic micromirror are examined. The macro model is introduced for the experimental study. The tension applied in the torsion bar is well controlled using the electromagnetic attraction. This controllability is suited for clearing the nonlinear nature. The tension is confirmed to have the effect to widen the controllable angle range of the mirror suppressing the pull-in. The pull-in angle is observed to increases to about 74% of the mechanical limit angle at the tension of 0,96 N. This is significantly larger than 44% of the case with the linear spring. The larger resonant frequency is maintained. The hardening of the spring can keep the balance with the electrostatic force over the limit of the linear spring. The observed features are explained reasonably with the combination of twisting and bending displacements of the torsion bar. 展开更多
关键词 MICROMIRROR electrostatic actuator PULL-IN nonlinear spring macro model
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A Fractional Micro-Macro Model for Crowds of Pedestrians Based on Fractional Mean Field Games 被引量:1
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作者 Kecai Cao Yang Quan Chen Daniel Stuart 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第3期261-270,共10页
Modeling a crowd of pedestrians has been considered in this paper from different aspects. Based on fractional microscopic model that may be much more close to reality, a fractional macroscopic model has been proposed ... Modeling a crowd of pedestrians has been considered in this paper from different aspects. Based on fractional microscopic model that may be much more close to reality, a fractional macroscopic model has been proposed using conservation law of mass. Then in order to characterize the competitive and cooperative interactions among pedestrians, fractional mean field games are utilized in the modeling problem when the number of pedestrians goes to infinity and fractional dynamic model composed of fractional backward and fractional forward equations are constructed in macro scale. Fractional micromacro model for crowds of pedestrians are obtained in the end. Simulation results are also included to illustrate the proposed fractional microscopic model and fractional macroscopic model, respectively. © 2014 Chinese Association of Automation. 展开更多
关键词 Control systems Electrical engineering
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Image processing algorithm acceleration using reconfigurable macro processor model 被引量:2
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作者 SunGuanKfu ChenHuaming LuHuanzhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2004年第2期110-114,共5页
The concept and advantage of reconfigurable technology is introduced. A kind of processor architecture of re configurable macro processor (RMP) model based on FPGA array and DSP is put forward and has been implemented... The concept and advantage of reconfigurable technology is introduced. A kind of processor architecture of re configurable macro processor (RMP) model based on FPGA array and DSP is put forward and has been implemented. Two image algorithms are developed: template-based automatic target recognition and zone labeling. One is estimating for motion direction in the infrared image background, another is line picking-up algorithm based on image zone labeling and phase grouping technique. It is a kind of 'hardware' function that can be called by the DSP in high-level algorithm. It is also a kind of hardware algorithm of the DSP. The results of experiments show the reconfigurable computing technology based on RMP is an ideal accelerating means to deal with the high-speed image processing tasks. High real time performance is obtained in our two applications on RMP. 展开更多
关键词 real-time image processing reconfigurable computing technology reconfigurable macro processor model template matching image zone labeling.
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Micro-macro models for viscoelastic fluids:modelling,mathematics and numerics
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作者 LE BRIS Claude LELIVRE Tony 《Science China Mathematics》 SCIE 2012年第2期353-384,共32页
This paper is an introduction to the modelling of viscoelastic fluids,with an emphasis on micromacro(or multiscale) models.Some elements of mathematical and numerical analysis are provided.These notes closely follow t... This paper is an introduction to the modelling of viscoelastic fluids,with an emphasis on micromacro(or multiscale) models.Some elements of mathematical and numerical analysis are provided.These notes closely follow the lectures delivered by the second author at the Chinese Academy of Science during the Workshop "Stress Tensor E?ects on Fluid Mechanics" in January 2010. 展开更多
关键词 VISCOELASTIC FLUIDS micro-macro models ENTROPY METHODS MONTE Carlo METHODS
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MODEL B-I FOR MACRO RECTANGULAR ELEMENT AND PROBLEMS OF INFLUENCE SURFACE FOR PLATE STRUCTURES
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作者 王进忠 何长华 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第12期1097-1106,共10页
Model B-I for marco rectangular element is presented for the first time in this paper. To establish the influence surf ace for resultant R of bending plates, a number of generalized distributive loads q are defined. I... Model B-I for marco rectangular element is presented for the first time in this paper. To establish the influence surf ace for resultant R of bending plates, a number of generalized distributive loads q are defined. It is shown by numerical examples that Model B-I and the formula for the generalized distributive loads advanced in this paper are featured by high accuracy, low memory space and flexibility in practical application, and that they are especially effective for plate structures subject to moving loads, such as the two-dimensional continuous plates of highway bridges and the flat stabs in piled jetty engineering. 展开更多
关键词 model B-I for macro rectangular element moving load influence surface generalized distributive load
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A statistical mechanics model of carbon nanotube macro-films
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作者 Y.An,1 X.Li,2 B.Q.Wei,2 and H.Jiang 1,a) 1) School for Engineering of Matter,Transport,and Energy,ArizonaStateUniversity,Tempe,AZ 85287,USA 2) Department of Mechanical Engineering,University of Delaware,Newark,DE 19716,USA 《Theoretical & Applied Mechanics Letters》 CAS 2011年第4期19-22,共4页
Carbon nanotube macro-films are two-dimensional films with micrometer thickness and centimeter by centimeter in-plane dimension.These carbon nanotube macroscopic assemblies have attracted significant attention from th... Carbon nanotube macro-films are two-dimensional films with micrometer thickness and centimeter by centimeter in-plane dimension.These carbon nanotube macroscopic assemblies have attracted significant attention from the material and mechanics communities recently because they can be easily handled and tailored to meet specific engineering needs.This paper reports the experimental methods on the preparation and characterization of single-walled carbon nanotube macro-films,and a statistical mechanics model on the deformation behavior of this material.This model provides a capability to optimize the synthesis process by comparing with the experiments. 展开更多
关键词 carbon nanotube macro-films statistical mechanics model
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Research on failure criterion of composite based on unified macro- and micro-mechanical model 被引量:6
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作者 Sun Zhigang Zhao Long +1 位作者 Chen Lei Song Yingdong 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第1期122-129,共8页
A new unified macro- and micro-mechanics failure analysis method for composite structures was developed in order to take the effects of composite micro structure into consideration. In this method, the macro stress di... A new unified macro- and micro-mechanics failure analysis method for composite structures was developed in order to take the effects of composite micro structure into consideration. In this method, the macro stress distribution of composite structure was calculated by commercial finite element analysis software. According to the macro stress distribution, the damage point was searched and the micro-stress distribution was calculated by reformulated finite-volume direct averaging micromechanics (FVDAM), which was a multi-scale finite element method for composite. The micro structure failure modes were estimated with the failure strength of constituents. A unidirectional composite plate with a circular hole in the center under two kinds of loads was analyzed with the traditional macro-mechanical failure analysis method and the unified macro- and micro-mechanics failure analysis method. The results obtained by the two methods are consistent, which show this new method's accuracy and efficiency. 展开更多
关键词 COMPOSITE Finite-volume direct averaging micromechanics Mechanics failure model Multi-scale finite element Unified macro and micro
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Three-Dimensional Nonlinear Dynamic Model and Macro Control of Real Estate
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作者 Dan Ma Shengwu Zhou Haojin Lv 《Intelligent Information Management》 2010年第5期325-328,共4页
In this paper, according to economics of real estate and macro-control theory, combine with the characteristics of the real estate market, macro-control of the real estate market is studied. After giving the dynamic m... In this paper, according to economics of real estate and macro-control theory, combine with the characteristics of the real estate market, macro-control of the real estate market is studied. After giving the dynamic model of three-dimensional nonlinear differential equations based on the total number of houses on the real estate business, the government’s averages housing investment funds and the standard price, systematically established the stability conditions of equilibrium point for this model. What’s more, through the use of extreme value analysis model, government funds have been invested in real estate business building devotion principles and the construction base of the real estate businessmen has also been estimated successfully. This provides the corresponding theoretical basis for government macro control policy-making. 展开更多
关键词 REAL ESTATE macro Control THREE-DIMENSIONAL Dynamic model EXTREME Value Analysis
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Micro-macro Unified Analysis of Flow Behavior of Particle-reinforced Metal Matrix Composites 被引量:2
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作者 张鹏 李付国 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2010年第2期252-259,共8页
This article presents a micro-macro unified model for predicting the deformation of metal matrix composites (MMCs). A macro-scale model is developed to obtain the proper boundary conditions for the micro-scale model... This article presents a micro-macro unified model for predicting the deformation of metal matrix composites (MMCs). A macro-scale model is developed to obtain the proper boundary conditions for the micro-scale model, which is used to assess the microstructural deformation of materials. The usage of the submodel technique in the analysis makes it possible to shed light on the stress and strain field at the microlevel. This is helpful to investigate the linkage between the microscopic and the macroscopic flow behavior of the composites. An iterative procedure is also proposed to find out the optimum parameters. The results show that the convergence can be attained after three iterations in computation. In order to demonstrate the reliability of mi- cro-macro unified model, results based on the continuum composite model are also investigated using the stress-strain relation of composite obtained from the iterations. By comparing the proposed unified model to the continuum composite model, it is clear that the former exhibits large plastic deformation in the case of little macroscopic deformation, and the stresses and strains obtained from the submodel are higher than those from the macroscopic deformation. 展开更多
关键词 metal matrix composites micro-macro unified model submodel flow behavior MICROSTRUCTURE
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A review of compact modeling for phase change memory
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作者 Feilong Ding Baokang Peng +4 位作者 Xi Li Lining Zhang Runsheng Wang Zhitang Song Ru Huang 《Journal of Semiconductors》 EI CAS CSCD 2022年第2期74-87,共14页
Phase change memory(PCM)attracts wide attention for the memory-centric computing and neuromorphic comput-ing.For circuit and system designs,PCM compact models are mandatory and their status are reviewed in this work.M... Phase change memory(PCM)attracts wide attention for the memory-centric computing and neuromorphic comput-ing.For circuit and system designs,PCM compact models are mandatory and their status are reviewed in this work.Macro mod-els and physics-based models have been proposed in different stages of the PCM technology developments.Compact model-ing of PCM is indeed more complex than the transistor modeling due to their multi-physics nature including electrical,thermal and phase transition dynamics as well as their interactions.Realizations of the PCM operations including threshold switching,set and reset programming in these models are diverse,which also differs from the perspective of circuit simulations.For the purpose of efficient and reliable designs of the PCM technology,open issues and challenges of the compact modeling are also discussed. 展开更多
关键词 phase change memory compact model macro model physics-based model
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Multi-scale modeling of hemodynamics in the cardiovascular system 被引量:4
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作者 Hao Liu Fuyou Liang +4 位作者 Jasmin Wong Takashi Fujiwara Wenjing Ye Ken-iti Tsubota Michiko Sugawara 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2015年第4期446-464,共19页
The human cardiovascular system is a closed- loop and complex vascular network with multi-scaled het- erogeneous hemodynamic phenomena. Here, we give a selective review of recent progress in macro-hemodynamic modeling... The human cardiovascular system is a closed- loop and complex vascular network with multi-scaled het- erogeneous hemodynamic phenomena. Here, we give a selective review of recent progress in macro-hemodynamic modeling, with a focus on geometrical multi-scale model- ing of the vascular network, micro-hemodynamic modeling of microcirculation, as well as blood cellular, subcellular, endothelial biomechanics, and their interaction with arter- ial vessel mechanics. We describe in detail the methodology of hemodynamic modeling and its potential applications in cardiovascular research and clinical practice. In addition, we present major topics for future study: recent progress of patient-specific hemodynamic modeling in clinical applica- tions, micro-hemodynamic modeling in capillaries and blood cells, and the importance and potential of the multi-scale hemodynarnic modeling. 展开更多
关键词 Multi-scale modeling. macro-hemodynamics.Micro-hemodynamics Cardiovascular system ENDOTHELIALCELL
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A micromechanical damage model for rocks and concretes under triaxial compression
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作者 任中俊 彭向和 +2 位作者 胡宁 杨春和 Xing-ming GUO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2009年第3期323-333,共11页
Based on analysis of deformation in an infinite isotropic elastic matrix containing an embedded elliptic crack, subject to far field triaxial compressive stress, the energy release rate and a mixed fracture criterion ... Based on analysis of deformation in an infinite isotropic elastic matrix containing an embedded elliptic crack, subject to far field triaxial compressive stress, the energy release rate and a mixed fracture criterion are obtained by using an energy balance approach. The additional compliance tensor induced by a single closed elliptic microcrack in a representative volume element and its in-plane growth is derived. The additional compliance tensor induced by the kinked growth of the elliptic microcrack is also obtained. The effect of the microcracks, randomly distributed both in geometric characteristics and orientations, is analyzed with the Taylor's scheme by introducing an appropriate probability density function. A micromechanical damage model for rocks and concretes under triaxial compression is obtained and experimentally verified. 展开更多
关键词 elliptic microcrack in-plane growth kinked growth energy release rate micro-macro damage model
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政策过程视域下县域医共体政策的价值取向、实践逻辑与优化路径 被引量:1
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作者 毛瑛 李浩然 +1 位作者 张静雅 谢涛 《西安交通大学学报(社会科学版)》 北大核心 2025年第4期82-91,共10页
县域医共体建设是提高县域医疗卫生资源配置和使用效率、提升医疗卫生服务可及性的重要举措。基于政策过程阶段论,回溯县域医共体政策价值取向,根据已有实践案例构建县域医共体建设实践逻辑模型,剖析政策价值取向与实践逻辑是否存在偏差... 县域医共体建设是提高县域医疗卫生资源配置和使用效率、提升医疗卫生服务可及性的重要举措。基于政策过程阶段论,回溯县域医共体政策价值取向,根据已有实践案例构建县域医共体建设实践逻辑模型,剖析政策价值取向与实践逻辑是否存在偏差,据此提出调整路径。研究发现,县域医共体政策形成了“采用多种政策工具,提升医疗卫生服务能力,促进人民健康”的价值取向,且在政策引领下,形成了“中央政策高位推动产生外部动力,促使县域内部搭建‘组织、资源、行政’三位一体运行机制产生内部动力,进而助力基层服务过程优化提质,最终实现系统与健康结果改善”的实践发展逻辑。县域医共体建设政策目标与实践逻辑总体一致,但仍有建设实践与政策目标存在偏差的状况,需要通过完善建设环节、再塑建设机制、探索建设新路径来优化政策与实践协调发展路径。 展开更多
关键词 县域医共体政策 卫生资源配置 医疗卫生服务体系 政策过程 健康系统宏观模型 模糊—冲突模型
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AI作曲技术的创新实践与研究 被引量:3
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作者 刘灏 《中国文艺评论》 2025年第1期27-34,I0001,I0002,共10页
随着大数据技术的完善,AI技术在音乐创作领域的应用日益广泛。AI作曲技术通过深度学习模型实现自动作曲,降低了音乐创作的门槛,使普通人也能参与专业创作。目前已有众多AI作曲平台及工具,如Magenta、Suno、天工SkyMusic等,本文首先分析... 随着大数据技术的完善,AI技术在音乐创作领域的应用日益广泛。AI作曲技术通过深度学习模型实现自动作曲,降低了音乐创作的门槛,使普通人也能参与专业创作。目前已有众多AI作曲平台及工具,如Magenta、Suno、天工SkyMusic等,本文首先分析了AI技术在音乐生成、风格迁移、音乐补全等方面的应用。其次,以上海音乐学院在教学实践中不断探索AI作曲的应用为例,展现其在非遗传承、声音疗愈等领域的强劲潜力。值得注意的是,虽然AI技术也对音乐艺术产生冲击,但音乐工作者应积极融合新技术,推动艺术与科技的共同发展。 展开更多
关键词 AI作曲技术 音乐生成 音乐大模型 声音疗愈 虚拟博物馆
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Investigation of Pile Construction and Productivity Loss: An Analysis of Macro Impact Factor
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作者 Minhaz Ahmed Wang Xu 《World Journal of Engineering and Technology》 2023年第4期932-964,共33页
Pile foundations are challenging to build due to subsurface obstacles, contractor ignorance, and difficulties with site planning. Given the unpredictable environment of the construction site, productivity losses durin... Pile foundations are challenging to build due to subsurface obstacles, contractor ignorance, and difficulties with site planning. Given the unpredictable environment of the construction site, productivity losses during pile work are to be thought possible. Prior to finishing a site pre-investigation, a foundation’s area is usually sampled for statistical reasons. There are studies on pile construction outside of Bangladesh that are supported by relevant empirical data in the literature. Since Bangladesh, which is regarded as a third-world country, is ignored in this regard, the literature currently available about pile building and the associated productivity loss is unable to provide adequate information or appropriate empirical data. Due to this pile-building sector in Bangladesh has been experiencing a decline in production for quite some time now. Before attempting to increase productivity in pile construction, it is essential to investigate the potential losses and the variables that might have an influence. This study aims to accomplish the following objectives: 1) identify the primary factors that have an impact on pile construction;2) develop an SVR model that accurately predicts productivity loss;and 3) figure out the projected loss by basing it on the historical scenario that is the most comparable to the current one. A Support Vector Regression (SVR) model was developed after a study of the relevant literature. This model enabled the collection of 110 pile building projects from five significant locations in Bangladesh. The model was constructed using a list of eight inputs in addition to a list of five macro elements (labor, management, environment, material, and equipment) (soil condition, pile type, pile material, project size, project location, pile depth, pile quantity, and equipment quantity). Using 10-way cross validation, the SVR achieves an accuracy of 87.2% in its predictions. On the basis of what has occurred in the past, we are able to estimate that there will be a loss of around 18.55 percent of the total output. A new perspective for engineers studying the delay factors with productivity loss is provided by the outcome of important tasks as it relates to loss in productivity and overall factors faced. In the building construction industry, effective management should place more emphasis on the correlation between productivity loss and the factors that cause it. Therefore, to represent the effect on productivity loss, real factors can be summed up as a decline in productivity loss. The findings of the study would urge specialists to concentrate on waste as a means of increasing overall production. 展开更多
关键词 Productivity Loss macro-Effect Factor Pile Construction Regression model SVR model
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基于SBFEM的锈蚀钢筋和混凝土间黏结-滑移数值模拟
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作者 杜成斌 赵志伟 《人民长江》 北大核心 2025年第10期197-205,共9页
针对锈蚀钢筋混凝土结构的力学性能评估问题,建立了基于比例边界有限元法(SBFEM)的计算框架。采用非线性弹簧单元模拟钢筋-混凝土界面黏结-滑移行为,通过非线性桁架单元表征锈蚀钢筋的力学性能,使用四叉树网格实现混凝土高效离散,引入... 针对锈蚀钢筋混凝土结构的力学性能评估问题,建立了基于比例边界有限元法(SBFEM)的计算框架。采用非线性弹簧单元模拟钢筋-混凝土界面黏结-滑移行为,通过非线性桁架单元表征锈蚀钢筋的力学性能,使用四叉树网格实现混凝土高效离散,引入非局部宏-微观损伤模型模拟混凝土开裂过程。拉拔试验模拟表明:该方法能准确模拟锈蚀界面的黏结-滑移行为;当弹簧间距≤黏结长度的1/4时,计算结果与试验数据吻合良好。三点弯曲试验结果显示:钢筋屈服后特性会显著影响荷载-位移曲线下降段,混凝土开裂后,钢筋力学性能主导结构响应。所提出的SBFEM框架可有效模拟锈蚀钢筋与混凝土的界面行为和结构整体力学性能退化过程,为锈蚀钢筋混凝土结构性能评估提供了可靠的分析工具。 展开更多
关键词 锈蚀钢筋 比例边界有限元法 黏结-滑移本构模型 非局部宏-微观损伤模型 混凝土
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