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基于24Model-D-ISM的地铁站火灾疏散影响因素研究
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作者 孙世梅 张家严 《中国安全科学学报》 CAS CSCD 北大核心 2024年第4期153-159,共7页
为预防地铁站火灾事故,深入了解地铁站火灾人员疏散影响因素间的内在联系与层次结构,基于第6版“2-4”模型(24Model)分析63起地铁站火灾疏散事故,充分考虑各个因素之间的交互作用,提取19个影响地铁站人员疏散的关键因素,建立地铁站火灾... 为预防地铁站火灾事故,深入了解地铁站火灾人员疏散影响因素间的内在联系与层次结构,基于第6版“2-4”模型(24Model)分析63起地铁站火灾疏散事故,充分考虑各个因素之间的交互作用,提取19个影响地铁站人员疏散的关键因素,建立地铁站火灾人员疏散影响因素指标体系;采用算子客观赋权法(C-OWA)改进决策试验与评价实验法(DEMATEL),确定地铁站火灾人员疏散的重要影响因素;在此基础上,采用解释结构模型(ISM)分析各个因素间的层次结构及相互作用路径,构建地铁站火灾人员疏散影响因素的多级递阶结构模型。研究结果表明:疏散引导、恐慌从众行为、人员拥挤为地铁站火灾人员疏散的关键影响因素;地铁站火灾人员疏散受表层因素、中间层因素、深层因素共同作用的影响,其中,疏散教育与培训、设施维护与检查、疏散预案等因素是根源影响因素,重视根源影响因素的改善有利于从本质上预防和控制事故的发生。 展开更多
关键词 “2-4”模型(24Model) 决策试验与评价实验法(DEMATEL) 解释结构模型(ISM) 地铁站 火灾疏散 影响因素
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基于改进24Model-ISM-SNA建筑工人不安全行为关联路径研究
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作者 赵平 刘钰 +1 位作者 靳丽艳 王佳慧 《工业安全与环保》 2024年第7期37-40,共4页
建筑施工现场环境复杂,为有效控制不安全行为发生,基于行为安全“2-4”模型对360份具有代表性的建筑安全事故调查报告进行分析,提取出22个不安全行为的主要影响因素。利用灰色关联分析方法(GRA)改进的集成ISM-SNA模型,将不安全行为风险... 建筑施工现场环境复杂,为有效控制不安全行为发生,基于行为安全“2-4”模型对360份具有代表性的建筑安全事故调查报告进行分析,提取出22个不安全行为的主要影响因素。利用灰色关联分析方法(GRA)改进的集成ISM-SNA模型,将不安全行为风险因素划分为表层、过渡层与深层,然后对风险因素进行可视化分析、中心度分析及凝聚子群分析,揭示了各致因因素间的关联关系和传导路径。结果表明,建筑工人不安全行为影响因素可划分成7级3阶的多级递阶结构,安全意识、现场监管、外部环境是建筑工人不安全行为的关键影响因素,同时现场监管和隐患排查到位能有效降低不安全行为的发生。 展开更多
关键词 建筑工人 不安全行为 24Model 解释结构模型(ISM) 社会网络分析(SNA)
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基于一种距离相关的超高维生存数据Model-Free特征筛选
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作者 潘莹丽 王昊宇 +1 位作者 喻佳丽 刘展 《湖北大学学报(自然科学版)》 CAS 2024年第1期122-132,共11页
随着大数据时代的来临,数据维度爆炸式增长,超高维数据的降维问题逐渐成为众多研究领域的热点话题。由于响应变量通常存在右删失,处理超高维完全数据的降维方法在右删失数据中将不再适用。本研究提出一种新的基于距离相关能有效处理超... 随着大数据时代的来临,数据维度爆炸式增长,超高维数据的降维问题逐渐成为众多研究领域的热点话题。由于响应变量通常存在右删失,处理超高维完全数据的降维方法在右删失数据中将不再适用。本研究提出一种新的基于距离相关能有效处理超高维右删失数据的特征筛选方法。首先利用距离相关系数计算每个协变量对响应变量的边际效应,建立与该系数有关的筛选指标,然后再根据事先确立的筛选准则进行特征筛选。提出的特征筛选方法不依赖任何模型结构假定,因此可以有效避免模型指定错误带来的不良后果。此外,该方法采用的距离协方差估计量是总体距离协方差的一个无偏估计,统计准确性和计算精度高。模拟和实证研究表明,提出的方法能在保留所有重要变量的前提下快速剔除与响应变量相关程度较弱的协变量,从而达到降低参数维数的目的。 展开更多
关键词 超高维数据 生存数据 距离相关 model-Free特征筛选
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Model-Based Systems Engineering Approach to Design a Human Settlement to Better Serve Displaced People
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作者 Anicet Adjahossou 《Open Journal of Applied Sciences》 2024年第4期865-880,共16页
The challenge of transitioning from temporary humanitarian settlements to more sustainable human settlements is due to a significant increase in the number of forcibly displaced people over recent decades, difficultie... The challenge of transitioning from temporary humanitarian settlements to more sustainable human settlements is due to a significant increase in the number of forcibly displaced people over recent decades, difficulties in providing social services that meet the required standards, and the prolongation of emergencies. Despite this challenging context, short-term considerations continue to guide their planning and management rather than more integrated, longer-term perspectives, thus preventing viable, sustainable development. Over the years, the design of humanitarian settlements has not been adapted to local contexts and perspectives, nor to the dynamics of urbanization and population growth and data. In addition, the current approach to temporary settlement harms the environment and can strain limited resources. Inefficient land use and ad hoc development models have compounded difficulties and generated new challenges. As a result, living conditions in settlements have deteriorated over the last few decades and continue to pose new challenges. The stakes are such that major shortcomings have emerged along the way, leading to disruption, budget overruns in a context marked by a steady decline in funding. However, some attempts have been made to shift towards more sustainable approaches, but these have mainly focused on vague, sector-oriented themes, failing to consider systematic and integration views. This study is a contribution in addressing these shortcomings by designing a model-driving solution, emphasizing an integrated system conceptualized as a system of systems. This paper proposes a new methodology for designing an integrated and sustainable human settlement model, based on Model-Based Systems Engineering and a Systems Modeling Language to provide valuable insights toward sustainable solutions for displaced populations aligning with the United Nations 2030 agenda for sustainable development. 展开更多
关键词 Humanitarian Settlement Human Settlement Sustainability Systems Engineering model-Based Systems Engineering Systems Modeling Language
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Cox模型中基于Model-X Knockoffs的高维控制变量选择方法
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作者 黄河 潘莹丽 《统计与决策》 CSSCI 北大核心 2023年第5期16-21,共6页
在生物医学、临床试验和流行病学等领域的研究中,由于获得生存数据的试验设计、观测时间的局限,以及观测对象在进入或退出试验时的个体差异等方面的原因,与所关注事件的发生时间相关的数据经常存在右删失。基于右删失生存数据解析协变... 在生物医学、临床试验和流行病学等领域的研究中,由于获得生存数据的试验设计、观测时间的局限,以及观测对象在进入或退出试验时的个体差异等方面的原因,与所关注事件的发生时间相关的数据经常存在右删失。基于右删失生存数据解析协变量和生存时间的关系时,应用最为广泛的统计模型是Cox模型。随着科学技术的进步,数据收集变得越来越容易,导致数据库规模越来越大、复杂性越来越高,数据的维度通常可以达到成百上千维,甚至更高。文章提出一种Cox模型中基于Model-X Knockoffs的高维控制变量选择方法。首先基于Knockoffs框架建立一个Knockoffs变量,并基于原始协变量和其相应的Knockoffs变量构造一个正则化的目标函数,然后通过求解目标函数的最优解构造一个统计量和基于数据的阈值,最后进行变量选择。模拟分析和实证研究结果表明:所提方法可以在变量选择的同时提供可靠的FDR控制,优于传统的LASSO方法。 展开更多
关键词 COX模型 model-X Knockoffs FDR控制 变量选择
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A Study of EM Algorithm as an Imputation Method: A Model-Based Simulation Study with Application to a Synthetic Compositional Data
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作者 Yisa Adeniyi Abolade Yichuan Zhao 《Open Journal of Modelling and Simulation》 2024年第2期33-42,共10页
Compositional data, such as relative information, is a crucial aspect of machine learning and other related fields. It is typically recorded as closed data or sums to a constant, like 100%. The statistical linear mode... Compositional data, such as relative information, is a crucial aspect of machine learning and other related fields. It is typically recorded as closed data or sums to a constant, like 100%. The statistical linear model is the most used technique for identifying hidden relationships between underlying random variables of interest. However, data quality is a significant challenge in machine learning, especially when missing data is present. The linear regression model is a commonly used statistical modeling technique used in various applications to find relationships between variables of interest. When estimating linear regression parameters which are useful for things like future prediction and partial effects analysis of independent variables, maximum likelihood estimation (MLE) is the method of choice. However, many datasets contain missing observations, which can lead to costly and time-consuming data recovery. To address this issue, the expectation-maximization (EM) algorithm has been suggested as a solution for situations including missing data. The EM algorithm repeatedly finds the best estimates of parameters in statistical models that depend on variables or data that have not been observed. This is called maximum likelihood or maximum a posteriori (MAP). Using the present estimate as input, the expectation (E) step constructs a log-likelihood function. Finding the parameters that maximize the anticipated log-likelihood, as determined in the E step, is the job of the maximization (M) phase. This study looked at how well the EM algorithm worked on a made-up compositional dataset with missing observations. It used both the robust least square version and ordinary least square regression techniques. The efficacy of the EM algorithm was compared with two alternative imputation techniques, k-Nearest Neighbor (k-NN) and mean imputation (), in terms of Aitchison distances and covariance. 展开更多
关键词 Compositional Data Linear Regression Model Least Square Method Robust Least Square Method Synthetic Data Aitchison Distance Maximum Likelihood Estimation Expectation-Maximization Algorithm k-Nearest Neighbor and Mean imputation
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基于Model-X Knockoffs的非概率样本倾向得分模型推断方法
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作者 刘展 郑俊博 +1 位作者 刘洋 潘莹丽 《统计与决策》 CSSCI 北大核心 2023年第4期10-15,共6页
大数据下的样本大多为非概率样本,其入样概率未知,同时可能面临着协变量较多甚至是高维的情况,那么如何对这种情况下的非概率样本进行推断值得探索。针对该问题,文章考虑到Model-X Knockoffs的降维特点,提出采用Model-X Knockoffs筛选... 大数据下的样本大多为非概率样本,其入样概率未知,同时可能面临着协变量较多甚至是高维的情况,那么如何对这种情况下的非概率样本进行推断值得探索。针对该问题,文章考虑到Model-X Knockoffs的降维特点,提出采用Model-X Knockoffs筛选出重要变量,建立Logistic倾向得分模型来估计非概率样本的入样概率或倾向得分,对总体进行推断,从而提高估计的精度,同时可控制变量选择的错误发现率与功效。模拟与实证研究结果表明:基于Model-X Knockoffs的Logistic倾向得分模型的总体均值估计相比一般的Logistic倾向得分模型和广义线性回归模型的总体均值估计,偏差更小、效率更高、估计效果更好,并且能很好地控制错误发现率的水平,功效值也接近1。 展开更多
关键词 非概率样本 model-X Knockoffs LASSO 倾向得分
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Model-Free Feature Screening via Maximal Information Coefficient (MIC) for Ultrahigh-Dimensional Multiclass Classification
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作者 Tingting Chen Guangming Deng 《Open Journal of Statistics》 2023年第6期917-940,共24页
It is common for datasets to contain both categorical and continuous variables. However, many feature screening methods designed for high-dimensional classification assume that the variables are continuous. This limit... It is common for datasets to contain both categorical and continuous variables. However, many feature screening methods designed for high-dimensional classification assume that the variables are continuous. This limits the applicability of existing methods in handling this complex scenario. To address this issue, we propose a model-free feature screening approach for ultra-high-dimensional multi-classification that can handle both categorical and continuous variables. Our proposed feature screening method utilizes the Maximal Information Coefficient to assess the predictive power of the variables. By satisfying certain regularity conditions, we have proven that our screening procedure possesses the sure screening property and ranking consistency properties. To validate the effectiveness of our approach, we conduct simulation studies and provide real data analysis examples to demonstrate its performance in finite samples. In summary, our proposed method offers a solution for effectively screening features in ultra-high-dimensional datasets with a mixture of categorical and continuous covariates. 展开更多
关键词 Ultrahigh-Dimensional Feature Screening model-FREE Maximal Information Coefficient (MIC) Multiclass Classification
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Model-Free Ultra-High-Dimensional Feature Screening for Multi-Classified Response Data Based on Weighted Jensen-Shannon Divergence
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作者 Qingqing Jiang Guangming Deng 《Open Journal of Statistics》 2023年第6期822-849,共28页
In ultra-high-dimensional data, it is common for the response variable to be multi-classified. Therefore, this paper proposes a model-free screening method for variables whose response variable is multi-classified fro... In ultra-high-dimensional data, it is common for the response variable to be multi-classified. Therefore, this paper proposes a model-free screening method for variables whose response variable is multi-classified from the point of view of introducing Jensen-Shannon divergence to measure the importance of covariates. The idea of the method is to calculate the Jensen-Shannon divergence between the conditional probability distribution of the covariates on a given response variable and the unconditional probability distribution of the covariates, and then use the probabilities of the response variables as weights to calculate the weighted Jensen-Shannon divergence, where a larger weighted Jensen-Shannon divergence means that the covariates are more important. Additionally, we also investigated an adapted version of the method, which is to measure the relationship between the covariates and the response variable using the weighted Jensen-Shannon divergence adjusted by the logarithmic factor of the number of categories when the number of categories in each covariate varies. Then, through both theoretical and simulation experiments, it was demonstrated that the proposed methods have sure screening and ranking consistency properties. Finally, the results from simulation and real-dataset experiments show that in feature screening, the proposed methods investigated are robust in performance and faster in computational speed compared with an existing method. 展开更多
关键词 Ultra-High-Dimensional Multi-Classified Weighted Jensen-Shannon Divergence model-FREE Feature Screening
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Can a global mean sea-level rise reduce the Last Interglacial model-data mismatch in East Asia?
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作者 Zhiqi Qian Tianao Xu +1 位作者 Zhongshi Zhang Chunju Huang 《Atmospheric and Oceanic Science Letters》 CSCD 2023年第5期121-128,共8页
末次间冰期有着丰富的重建和模拟资料,为研究未来温暖气候提供了一个理想的参考.然而,关于末次间冰期的东亚气候,模拟与重建的结果间长期存在着不匹配的情况,模拟结果普遍较重建结果更为冷干。本研究利用挪威地球系统模式(NorESM1-F),... 末次间冰期有着丰富的重建和模拟资料,为研究未来温暖气候提供了一个理想的参考.然而,关于末次间冰期的东亚气候,模拟与重建的结果间长期存在着不匹配的情况,模拟结果普遍较重建结果更为冷干。本研究利用挪威地球系统模式(NorESM1-F),探讨了在末次间冰期模拟试验中纳入全球平均海平面上升能否减少模式-数据的不匹配.该试验结果表明,海平面上升情况下东亚地区会产生一定的增温增湿效应,但不足以消除模式-数据不匹配.基于这些结果,作者探讨了其它可能造成不匹配的因素以供进一步研究. 展开更多
关键词 末次间冰期 海平面上升 模式-数据不匹配
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Model-View-Controller设计模式实例研究 被引量:12
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作者 李赤林 王琳 《计算机与现代化》 2003年第3期12-14,18,共3页
从MVC的起源谈起,以一个十分简单的Java例子来说明MVC的设计方式,最后以图解的方式揭示了MVC在实际运用中所采用的具体做法。
关键词 model-VIEW-CONTROLLER 实例 软件设计模式 面向对象 图形界面
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Advancing Scientific Rigor: Towards a Universal Informational Criterion for Assessing Model-Phenomenon Mismatch
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2023年第7期1817-1836,共20页
The escalating costs of research and development, coupled with the influx of researchers, have led to a surge in published articles across scientific disciplines. However, concerns have arisen regarding the accuracy, ... The escalating costs of research and development, coupled with the influx of researchers, have led to a surge in published articles across scientific disciplines. However, concerns have arisen regarding the accuracy, validity, and reproducibility of reported findings. Issues such as replication problems, fraudulent practices, and a lack of expertise in measurement theory and uncertainty analysis have raised doubts about the reliability and credibility of scientific research. Rigorous assessment practices in certain fields highlight the importance of identifying potential errors and understanding the relationship between technical parameters and research outcomes. To address these concerns, a universally applicable criterion called comparative certainty is urgently needed. This criterion, grounded in an analysis of the modeling process and information transmission, accumulation, and transformation in both theoretical and applied research, aims to evaluate the acceptable deviation between a model and the observed phenomenon. It provides a theoretically grounded framework applicable to all scientific disciplines adhering to the International System of Units (SI). Objective evaluations based on this criterion can enhance the reproducibility and reliability of scientific investigations, instilling greater confidence in published findings. Establishing this criterion would be a significant stride towards ensuring the robustness and credibility of scientific research across disciplines. 展开更多
关键词 Amount of Information Information Channel Measurement MODEL System of Units Uncertainty Underwater Electrical Discharge
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Use of models in large-area forest surveys: comparing model-assisted, model-based and hybrid estimation 被引量:7
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作者 Goran Stahl Svetlana Saarela +8 位作者 Sebastian Schnell Soren Holm Johannes Breidenbach Sean P. Healey Paul L. Patterson Steen Magnussen Erik Naesset Ronald E. McRoberts Timothy G. Gregoire 《Forest Ecosystems》 SCIE CSCD 2016年第2期153-163,共11页
This paper focuses on the use of models for increasing the precision of estimators in large-area forest surveys. It is motivated by the increasing availability of remotely sensed data, which facilitates the developmen... This paper focuses on the use of models for increasing the precision of estimators in large-area forest surveys. It is motivated by the increasing availability of remotely sensed data, which facilitates the development of models predicting the variables of interest in forest surveys. We present, review and compare three different estimation frameworks where models play a core role: model-assisted, model-based, and hybrid estimation. The first two are well known, whereas the third has only recently been introduced in forest surveys. Hybrid inference mixes design- based and model-based inference, since it relies on a probability sample of auxiliary data and a model predicting the target variable from the auxiliary data.We review studies on large-area forest surveys based on model-assisted, model- based, and hybrid estimation, and discuss advantages and disadvantages of the approaches. We conclude that no general recommendations can be made about whether model-assisted, model-based, or hybrid estimation should be preferred. The choice depends on the objective of the survey and the possibilities to acquire appropriate field and remotely sensed data. We also conclude that modelling approaches can only be successfully applied for estimating target variables such as growing stock volume or biomass, which are adequately related to commonly available remotely sensed data, and thus purely field based surveys remain important for several important forest parameters. 展开更多
关键词 Design-based inference model-assisted estimation model-based inference Hybrid inference Nationalforest inventory Remote sensing Sampling
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Review of Software Model-Checking Techniques for Dealing with Error Detection in Program Codes
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作者 Ednah Olubunmi Aliyu 《Journal of Software Engineering and Applications》 2023年第6期170-192,共23页
Debugging software code has been a challenge for software developers since the early days of computer programming. A simple need, because the world is run by software. So perhaps the biggest engineering challenge is f... Debugging software code has been a challenge for software developers since the early days of computer programming. A simple need, because the world is run by software. So perhaps the biggest engineering challenge is finding ways to make software more reliable. This review provides an overview of techniques developed over time in the field of software model checking to solve the problem of detecting errors in program code. In addition, the challenges posed by this technology are discussed and ways to mitigate them in future research and applications are proposed. A comprehensive examination of the various model verification methods used to detect program code errors is intended to lay the foundation for future research in this area. 展开更多
关键词 Software Model Checking Symbolic Execution State Explosion ABSTRACTION Test Case Generations
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Model-41打印机在单片机系统中的应用
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作者 黄赛清 张国瑱 黄兆林 《上海海运学院学报》 1991年第4期85-92,共8页
本文分析了Model-41型打印机的工作原理,介绍了利用MCS-51单片机改进打印机功能的方法,给出了实用的微机接口硬件和控制程序,並附有实例。
关键词 model-41 打印机 微处理机
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NDT-Suite: A Methodological Tool Solution in the Model-Driven Engineering Paradigm
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作者 Julián Alberto García-García María José Escalona +1 位作者 Francisco José Domínguez-Mayo Alberto Salido 《Journal of Software Engineering and Applications》 2014年第4期206-217,共12页
Although the Model-Driven paradigm is being accepted in the research environment as a very useful and powerful option for effective software development, its real application in the enterprise context is still a chall... Although the Model-Driven paradigm is being accepted in the research environment as a very useful and powerful option for effective software development, its real application in the enterprise context is still a challenge for software engineering. Several causes can be stacked out, but one of them can be the lack of tool support for the efficient application of this paradigm. This paper presents a set of tools, grouped in a suite named NDT-Suite, which under the Model-Driven paradigm offer a suitable solution for software development. These tools explore different options that this paradigm can improve such as, development, quality assurance or requirement treatment. Besides, this paper analyses how they are being successfully applied in the industry. 展开更多
关键词 model-Driven Web Engineering model-BASED SUITE TOOLS PRACTICAL Experiences NDT NDT-Suite
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Model-View-Controller架构用于中医舌诊网络化教学 被引量:2
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作者 叶美玲 沈淑敏 +1 位作者 陈兴夏 廖福龙 《北京生物医学工程》 2007年第4期425-427,共3页
目的运用Model-View-Controller架构于因特网,设计与研发中医舌诊教学的网站。方法本因特网教学系统使用Websphere6.0服务器、DB28.1.7数据库、Java Server Faces、Structure Query Language、HTML以及JavaScript等共同开发而成。邀请8... 目的运用Model-View-Controller架构于因特网,设计与研发中医舌诊教学的网站。方法本因特网教学系统使用Websphere6.0服务器、DB28.1.7数据库、Java Server Faces、Structure Query Language、HTML以及JavaScript等共同开发而成。邀请85位大学护理学生参与测试。结果中医舌诊网站含盖八大相关部分。学习成效测试结果显示,网络教学方式可增加学生相关的专业知识。 展开更多
关键词 模式-显示-控制 舌诊 因特网
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Model-Based Degree Estimation of Unbalance and Misalignment in Flexible Coupling-rotor System 被引量:5
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作者 LI Changyou XU Minqiang +2 位作者 GUO Song WANG Yuewu WANG Rixin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第4期550-556,共7页
The condition of rotor system must be assessed in order to develop condition-based maintenance for rotating machinery. It is determined by multiple variables such as unbalance degree, misalignment degree, the amount o... The condition of rotor system must be assessed in order to develop condition-based maintenance for rotating machinery. It is determined by multiple variables such as unbalance degree, misalignment degree, the amount of bending deformation of the shaft, occurrence of shaft crack of rotor system and so on. The estimation of the degrees of unbalance and misalignment in flexible coupling-rotor system is discussed. The model-based approach is employed to solve this problem. The models of the equivalent external loads for unbalance and misalignment are derived and analyzed. Then, the degrees of unbalance and misalignment are estimated by analyzing the components of the equivalent external loads of which the frequencies are equal to the 1 and 2 times running frequency respectively. The equivalent external loads are calculated according to the dynamic equation of the original rotor system and the differences between the dynamical responses in normal case and the vibrations when the degree of unbalance or misalignment or both changes. The denoise method based on bandpass filter is used to decrease the effect of noise on the estimation accuracy. The numerical examples are given to show that the proposed approach can estimate the degrees of unbalance and misalignment of the flexible coupling-rotor system accurately. 展开更多
关键词 model-based approach degree estimation MISALIGNMENT UNBALANCE rotor system flexible coupling
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Experts' Knowledge Fusion in Model-Based Diagnosis Based on Bayes Networks 被引量:5
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作者 Deng Yong & Shi Wenkang School of Electronics & Information Technology, Shanghai Jiaotong University, Shanghai 200030, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第2期25-30,共6页
In previous researches on a model-based diagnostic system, the components are assumed mutually independent. Howerver , the assumption is not always the case because the information about whether a component is faulty ... In previous researches on a model-based diagnostic system, the components are assumed mutually independent. Howerver , the assumption is not always the case because the information about whether a component is faulty or not usually influences our knowledge about other components. Some experts may draw such a conclusion that 'if component m 1 is faulty, then component m 2 may be faulty too'. How can we use this experts' knowledge to aid the diagnosis? Based on Kohlas's probabilistic assumption-based reasoning method, we use Bayes networks to solve this problem. We calculate the posterior fault probability of the components in the observation state. The result is reasonable and reflects the effectiveness of the experts' knowledge. 展开更多
关键词 model-based diagnosis Experts' knowledge Probabilistic assumption-based reasoning Bayes networks.
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Model-based framework for multi-axial real-time hybrid simulation testing 被引量:4
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作者 Gaston A.Fermandois Billie F.Spencer,Jr. 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2017年第4期671-691,共21页
Real-time hybrid simulation is an efficient and cost-effective dynamic testing technique for performance evaluation of structural systems subjected to earthquake loading with rate-dependent behavior. A loading assembl... Real-time hybrid simulation is an efficient and cost-effective dynamic testing technique for performance evaluation of structural systems subjected to earthquake loading with rate-dependent behavior. A loading assembly with multiple actuators is required to impose realistic boundary conditions on physical specimens. However, such a testing system is expected to exhibit significant dynamic coupling of the actuators and suffer from time lags that are associated with the dynamics of the servo-hydraulic system, as well as control-structure interaction (CSI). One approach to reducing experimental errors considers a multi-input, multi-output (MIMO) controller design, yielding accurate reference tracking and noise rejection. In this paper, a framework for multi-axial real-time hybrid simulation (maRTHS) testing is presented. The methodology employs a real-time feedback-feedforward controller for multiple actuators commanded in Cartesian coordinates. Kinematic transformations between actuator space and Cartesian space are derived for all six-degrees-of- freedom of the moving platform. Then, a frequency domain identification technique is used to develop an accurate MIMO transfer function of the system. Further, a Cartesian-domain model-based feedforward-feedback controller is implemented for time lag compensation and to increase the robustness of the reference tracking for given model uncertainty. The framework is implemented using the 1/5th-scale Load and Boundary Condition Box (LBCB) located at the University of Illinois at Urbana- Champaign. To demonstrate the efficacy of the proposed methodology, a single-story frame subjected to earthquake loading is tested. One of the columns in the fraane is represented physically in the laboratory as a cantilevered steel column. For real- time execution, the numerical substructure, kinematic transformations, and controllers are implemented on a digital signal processor. Results show excellent performance of the maRTHS framework when six-degrees-of-freedom are controUed at the interface between substructures. 展开更多
关键词 real-time hybrid simulation multiple actuators dynamic coupling kinematic transformations model-basedcompensation
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