检索结果-内蒙古大学图书馆

Two families of dual-explicit model-based integration algorithms with controllable numerical damping for structural dynamic problems

引用

MECHANICAL SYSTEMS AND SIGNAL PROCESSING 2024年 218卷

作者： Fu, Bo Ilunga, Stephane Lavery Chen, Jin Changan Univ Sch Civil Engn Xian 710061 Peoples R China Shandong Jianzhu Univ Key Lab Bldg Struct Retrofitting & Underground Spa Minist Educ Jinan 250101 Peoples R China

Based on the recently proposed multi-sub-step implicit beta 1/beta 2-Bathe method and a novel mapping strategy on the error equation, this paper presents two families of dual-explicit model-based integration algorithms for solving linear and nonlinear dynamic problems. Firstly, the dualexplicit formulations of the well-known Chen and Ricles (CR) algorithm are adopted for the new algorithms. By matching the error equations of the new algorithms and the implicit beta 1/beta 2Bathe method, the model-based integration parameters of the new algorithms are then derived. After analyzing the numerical properties of the two algorithms, it can be found that they are unconditionally stable for linear and nonlinear softening dynamic problems when the governing integration parameters are within specific ranges. Besides the two algorithms' numerical dispersion and energy dissipation are identical to the parent algorithm, i.e., the beta 1/beta 2-Bathe method. The overshooting issue of the proposed algorithms is less prominent than in some representative model-based algorithms. Finally, two numerical examples are used to investigate the computational efficiency and accuracy of the new algorithms compared to the parent algorithm and some existing model-based algorithms, including those with controllable damping, i.e., the KR-alpha and MKR-alpha methods. The results show that the two families of new algorithms are less computationally expensive than the parent algorithm as they adopt dual-explicit and single-step formulation. In addition, it is also observed that the developed algorithms have a better performance of damping out the spurious effect at high modes than the KR-alpha and MKR-alpha methods.

关键词： integration algorithm Model -based Numerical damping Explicit

来源：评论

学校读者我要写书评

暂无评论

Stability analysis of substructure shake table testing using two families of model-based integration algorithms

引用

SOIL DYNAMICS AND EARTHQUAKE ENGINEERING 2019年 126卷 105777-000页

作者： Fu, Bo Kolay, Chinmoy Ricles, James Jiang, Huanjun Wu, Tao Changan Univ Sch Civil Engn Xian 710061 Shaanxi Peoples R China Indian Inst Technol Kanpur Dept Civil Engn Kanpur 208016 Uttar Pradesh India Lehigh Univ Dept Civil & Environm Engn Bethlehem PA 18015 USA Tongji Univ Coll Civil Engn Shanghai 200092 Peoples R China

In implementing a substructure shake table testing (SSTT), the complete structure is divided into the experimental and the analytical substructures, which are driven by shake table and numerically simulated in a computer, respectively. A number of unconditionally stable and explicit integration algorithms referred to as model-based algorithms with highly computational efficiency have been developed to meet the requirement of real-time in conducting SSTT. This study aims to comprehensively investigate the stability of the SSTT system using two recently proposed model-based integration algorithms with controllable numerical energy dissipation, i.e., Kolay-Ricles-alpha (KR-alpha) algorithms and modified KR-alpha (MKR-alpha) algorithms. The SSTT system for the 2-degree-of-freedom (2-DOF) structures are firstly formulated. In order to take the contribution of the experimental substructure into consideration, the dynamic condensation is adopted to calculate the integration parameters for the analytical substructure. The discrete transfer function of the 2-DOF-SSTT system are derived. The influences of the mass ratio, the frequency ratio and the time step on the stability of the SSTT system are comprehensively investigated by using the discrete control theory. The results show that for larger values of the mass ratio, the frequency ratio and the time step have negative impact on the stability of the SSTT system. In addition, a subfamily of the MKR-alpha algorithms along with the dynamic condensation can always ensure the SSTT system stable.

关键词： Substructure shake table testing Stability analysis integration algorithm Discrete control theory Dynamic condensation

来源：评论

学校读者我要写书评

暂无评论

A New Family of Explicit Model-Based integration algorithms for Structural Dynamic Analysis

引用

INTERNATIONAL JOURNAL OF STRUCTURAL STABILITY AND DYNAMICS 2019年第6期19卷

作者： Fu, Bo Feng, De-Cheng Jiang, Huanjun Changan Univ Sch Civil Engn Xian 710061 Shaanxi Peoples R China Southeast Univ Minist Educ Key Lab Concrete & Prestressed Concrete Struct Nanjing 210096 Jiangsu Peoples R China Tongji Univ Coll Civil Engn Shanghai 200092 Peoples R China

A new family of explicit model-based integration algorithms for solving the equations of motion for linear and nonlinear systems is developed. These algorithms are also known as structure-dependent algorithms because the integration parameters are functions of the complete model of the structural system. A variety of numerical properties of the proposed algorithms, including consistency and local truncation error, stability, numerical dispersion and energy dissipation, overshooting, and frequency response under arbitrary excitation, are investigated using the discrete control theory and amplification matrix for linear elastic systems. In addition, the discrete control theory is applied for assessing the stability of the proposed algorithms for nonlinear structural systems. It is observed that the proposed algorithms exhibit the same numerical characteristics as the well-known Newmark family of integration algorithms. Compared with three existing model-based integration algorithms, i.e. the Chen-Ricles, modified Chen-Ricles, and Gui's algorithms, the proposed algorithms possess more general and versatile numerical features. As a result, the new family of explicit model-based integration algorithms can be potentially used to solve complicated linear and nonlinear structural dynamics problems.

关键词： integration algorithm numerical stability discrete control theory amplification matrix model-based algorithms numerical damping

来源：评论

学校读者我要写书评

暂无评论

Numerical integration of rate-independent BCC single crystal plasticity models: comparative study of two classes of numerical algorithms

引用

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING 2016年第5期108卷 363-422页

作者： Akpama, Holanyo K. Ben Bettaieb, Mohamed Abed-Meraim, Farid Arts & Metiers ParisTech CNRS UMR 7239 LEM3 4 Rue Augustin Fresnel F-57078 Metz 3 France Univ Lorraine DAMAS Lab Excellence Design Alloy Met Low mAss Struct Nancy France

In an incremental formulation suitable to numerical implementation, the use of rate-independent theory of crystal plasticity essentially leads to four fundamental problems. The first is to determine the set of potentially active slip systems over a time increment. The second is to select the active slip systems among the potentially active ones. The third is to compute the slip rates (or the slip increments) for the active slip systems. And the last problem is the possible non-uniqueness of slip rates. The purpose of this paper is to propose satisfactory responses to the aforementioned first three issues by presenting and comparing two novel numerical algorithms. The first algorithm is based on the usual return-mapping integration scheme, while the second follows the so-called ultimate scheme. The latter is shown to be more relevant and efficient than the former. These comparative performances are illustrated through various numerical simulations of the mechanical behavior of single crystals and polycrystalline aggregates subjected to monotonic and complex loadings. Although these algorithms are applied in this paper to body-centered-cubic crystal structures, they are quite general and suitable for integrating the constitutive equations for other crystal structures (e.g., face centered cubic and hexagonal close packed). Copyright (C) 2016 John Wiley & Sons, Ltd.

关键词： integration algorithm finite strain crystal plasticity rate-independent framework Schmid's law multisurface plasticity

来源：评论

学校读者我要写书评

暂无评论

Implicit integration of plasticity models for granular materials

引用

COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING 2003年第31-32期192卷 3471-3488页

作者： Ahadi, A Krenk, S Lund Univ Div Mech S-22100 Lund Sweden Tech Univ Denmark Dept Mech Engn DK-2800 Lyngby Denmark

A stress integration algorithm for granular materials based on fully implicit integration with explicit updating is presented. In the implicit method the solution makes use of the gradient to the potential surface at the final stress state which is unknown. The final stress and hardening parameters are determined solving the non-linear equations iteratively so that the stress increment fulfills the consistency condition. The integration algorithm is applicable for models depending on all the three stress invariants and it is applied to a characteristic state model for granular material. Since tensile stresses are not supported the functions and their derivatives are not representative outside the compressive octant of the principal stress space. The elastic predictor is therefore preconditioned in order to ensure that the first predictor is within the valid region. Capability and robustness of the integration algorithm are illustrated by simulating both drained and undrained triaxial tests on sand. The algorithm is developed in a standard format which can be implemented in several general purpose finite element codes. It has been implemented as an ABAQUS subroutine, and a traditional geotechnical problem of a flexible strip footing resting on a surface of sand is investigated in order to demonstrate the global accuracy and stability of the numerical solution. (C) 2003 Elsevier B.V. All rights reserved.

关键词： integration algorithm granular materials FE implementation footing analysis large strains

来源：评论

学校读者我要写书评

暂无评论

REStRAIN: Conceptualization of Agile Process Tools integration with Reference to the Aerospace Industry

引用

JOURNAL OF AEROSPACE INFORMATION SYSTEMS 2021年第4期18卷 144-156页

作者： Khalfallah, Malik Airbus DS Space Syst Engn Dept F-31 Toulouse France

This paper describes the development of a framework that integrates engineering software and agile tools based on ontologies and business rules. The aim of this integration is to help project managers specify their own rules of integration between development software and agile tools. This integration circumvents the limitations of on-the-shelf plugins that perform a very basic integration that not only fails to satisfy the complex needs of project managers but also provides insufficient customization possibilities. A formalization of the domain knowledge ontology and its extension are presented. A generic integration algorithm is presented, and some of its performance properties are detailed. To examine the application and validation of the framework, it is deployed for the integration of spacecraft data definition software with issue management systems. This deployment shows how project managers can specify the integration rules that give them the appropriate feedback information at project level after spacecraft data updates. The evaluation of the framework is conducted at two stages. At the time of design, the usability of the framework is evaluated, and it is shown that the general usability criterion is 4.15 on a Likert-type five-point response scale. Additionally, a comparison with on-the-shelf integration plugins shows that less cognitive effort is required from project managers to customize the presented framework integration rules. At run time, the execution time of the presented framework integration algorithm is evaluated. This evaluation shows that even for updates of large data files on the development software, the agile tools are updated following project managers' integration rules in a reasonable time.

关键词： Aerospace Industry integration algorithm Unified Modeling Language Telemetry Spacecraft System Integrated Development Environments Consultative Committee for Space Data Systems Cyber Physical System Systems Software Systems Engineering

来源：评论

学校读者我要写书评

暂无评论

Discontinuous time-integration method for dynamic contact impact problems

引用

AIAA JOURNAL 1999年第7期37卷 874-880页

作者： Cho, JY Kim, SJ Seoul Natl Univ Dept Aerosp Engn Kwanak Ku Seoul 151742 South Korea

A new time-integration method is proposed using the generalized derivative concept to simulate the dynamic phenomena with sudden constraint occurring in dynamic contact/impact problems. By the adoption of the generalized derivative concept and the jump assumption, discontinuity can be incorporated in time integration, and as a result, the algorithm does not need any other special consideration of jumps in dynamic field variables due to sudden constraint, such as dynamic contact-release conditions. To observe the characteristics of the proposed time-integration method, stability and convergence analyses are carried out. The analyses prove that the proposed method with linear approximation in the time domain yields unconditional stability and third-order accuracy In numerical tests, several dynamic contact/impact problems are analyzed by straightforward application of the proposed time-integration method with the exterior penalty method. From the tests, it is shown that the proposed time-integration method can be used successfully with the penalty method in numerical simulations of dynamic contact/impact problems.

关键词： Numerical Simulation Finite Element Approximation Composite Structures integration algorithm Material Properties Structural System Numerical integration Poisson's Ratio Plane Strain Dirac Delta Function

来源：评论

学校读者我要写书评

暂无评论

XACML Policy integration algorithms Based on Attribute Numericalization

XACML Policy Integration Algorithms Based on Attribute Numer...

引用

2011 13th IEEE Joint International Computer Science and Information Technology Conference(JICSIT 2011)

作者： Dongliang Jiao 1,2 , Liu Lianzhong 1 1.Key Laboratory of Beijing Network Technology Beihang University Beijing, China Li Ying 1 , Ma Shilong 2 2.State Key Laboratory of Software Development Environment Beihang University, Beijing, China

XACML provides a flexible and mechanism-independ- ent representation of access policies that vary in granularities. While XACML fits well with the security requirements of a single enterprise, it does not address the requirements of virtual enterprises in which several autonomous subjects collaborate by sharing their resources to provide better services to customers. With the explosive growth of web applications deployed on the Internet, XACML policies grow rapidly in size and complexity, which leads to longer request processing time. This article addresses the problem of integration authorization specifications that may be independently stated. We propose a new XACML policy integration algorithm based- PIABNC, and describe the steps of it in detail, finally, to evaluate the performance of PIABNC.

关键词： component access control attribute XACML Policy integration algorithm

来源：评论

学校读者我要写书评

暂无评论

Finite strain viscoplasticity with nonlinear kinematic hardening: Phenomenological modeling and time integration

引用

COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING 2008年第21-24期197卷 2015-2029页

作者： Shutov, A. V. Kreissig, R. Tech Univ Chemnitz Inst Mech & Thermodynam D-09111 Chemnitz Germany

This article deals with a viscoplastic material model of overstress type. The model is based on a multiplicative decomposition of the deformation gradient into elastic and inelastic part. An additional multiplicative decomposition of inelastic part is used to describe a nonlinear kinematic hardening of Armstrong-Frederick type. Two implicit time-stepping methods are adopted for numerical integration of evolution equations, such that the plastic incompressibility constraint is exactly satisfied. The first method is based on the tensor exponential. The second method is a modified Euler-backward method. Special numerical tests show that both approaches yield similar results even for finite inelastic increments. The basic features of the material response, predicted by the material model, are illustrated with a series of numerical simulations. (C) 2008 Elsevier B.V. All rights reserved.

关键词： viscoplasticity finite strains kinematic hardening inelastic incompressibility integration algorithm material testing

来源：评论

学校读者我要写书评

暂无评论

integration of identification and vibration control of time-varying structures subject to unknown seismic ground excitation

引用

JOURNAL OF VIBRATION AND CONTROL 2020年第15-16期26卷 1330-1344页

作者： Lei, Ying Lu, Jubin Huang, Jinshan Xiamen Univ Sch Architecture & Civil Engn Xiamen 361005 Peoples R China

The synthesis of structural health monitoring and vibration control is important in order to provide facilities for constructing smart structures. In recent years, some techniques have been developed to integrate structural identification and optimal vibration control. However, it is still challenging to integrate the identification and vibration control of time-varying structures subject to unknown earthquake excitation. The main difficulties are that structural dynamic responses collected by a simple harmonic motion system are absolute responses under unknown earthquake ground motion while previous identification approaches for unknown external excitation are not applicable for this situation and the need of an efficient algorithm to accurately track the various scenarios of time-varying structures with inexpensive computation to ensure the real-time performance requested by structural vibration control. In this paper, a novel algorithm is presented, in which structural time-varying parameters are treated as 'virtual unknown inputs' to the underlying time-invariant structure, a generalized Kalman filter with unknown inputs is proposed for joint identification of joint structural state, unknown earthquake excitation and 'virtual unknown inputs' with only partially measured structural absolute responses, and the identification results are integrated in real-time with the instantaneous optimal control scheme to reach the goal of optimal semi-active control provided by magneto-rheological dampers. Some numerical examples of integrated identification and vibration control of various time-varying structures subject to unknown earthquake excitation are used to demonstrate the performances of the proposed algorithm.

关键词： integration algorithm time-varying system structural identification Kalman filter with unknown input absolute response instantaneous optimal control

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：