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1 – 10 of over 114000Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the…
Abstract
Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.
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Nahid Darooghe Arefi, Hassan Bahrololoum, Reza Andam and Aliakbar Hasani
Sustainable development of entrepreneurship could be comprehensively analyzed using a simulation model for entrepreneurship ecosystem based on the system dynamics approach. Thus…
Abstract
Purpose
Sustainable development of entrepreneurship could be comprehensively analyzed using a simulation model for entrepreneurship ecosystem based on the system dynamics approach. Thus, a complete analysis of the entrepreneurship ecosystem is of high importance. However, an effective analysis of entrepreneurship ecosystem involves many challenges, such as the presence of several factors which interact with each other in various ways with different complex effects in time. Therefore, the approach used in this study is employing analysis of entrepreneurship ecosystems in sports industry using analysis of dynamic systems.
Design/methodology/approach
Several applied issues such as entrepreneurship opportunities, infrastructures, market opportunities and entrepreneurship space in the borders of the dynamic model developed based on the literature and experts' opinion. Finally, a set of strategies based on experts' opinion are ranked with the objective of improvement of evaluation measures using network analysis decision-making approach and fuzzy TOPSIS.
Findings
The results obtained indicate the important role of sports entrepreneurship opportunities, sports tourism, market opportunities, entrepreneurship infrastructures and entrepreneurship-oriented environment in the development of sports entrepreneurship infrastructure in Iran. The credibility and efficiency of the proposed model for analysis of sports entrepreneurship have been ultimately shown.
Originality/value
A holistic approach is proposed based on the hybrid system dynamics approach and fuzzy decision-making method to analyses sports entrepreneurship ecosystem.
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Chin-Tsung Hsieh, Her-Terng Yau and Cheng-Chi Wang
This study aims to investigate the dynamic motion of an ultrasonic machining system comprising two Duffing oscillators, each with a single degree of freedom. After derivation of…
Abstract
Purpose
This study aims to investigate the dynamic motion of an ultrasonic machining system comprising two Duffing oscillators, each with a single degree of freedom. After derivation of the differential equations of the system using the Lagrange equations and dimensionless time, numerical analysis was used to observe changes in the system caused by differences in excitation frequency.
Design/methodology/approach
To suppress this effect and improve performance, proportional differential (PD) control was used. The integral absolute error was used as the fitness function, and particle swarm optimization was used to find the best value for the gain constant of the PD controller.
Findings
The results showed that with specific changes of excitation frequency, the dynamic motion of the system became nonlinear and chaotic behavior resulted. This made the system unstable and affected performance.
Originality/value
A range of methods, including fuzzy control, was used to analyze the results, and exhaustive laboratory work was carried out. Means of control were found that were effective in suppressing the chaotic behavior, and differences in response to control were investigated and verified. The findings of this study can be used as a basis for system parameter settings or control circuit design.
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Yue Wang, Di Wu, Lei Wang and Xiaojun Wang
This paper aims to propose a novel statistic energy analysis method with fuzzy parameters to study the dynamic and acoustic responses of coupled system with fuzzy parameters…
Abstract
Purpose
This paper aims to propose a novel statistic energy analysis method with fuzzy parameters to study the dynamic and acoustic responses of coupled system with fuzzy parameters, which can expand the applied range of statistic energy analysis method in engineering to some extent.
Design/methodology/approach
On the basis of the property of membership level, the uncertain fuzzy parameters are expressed as the interval forms. Interval mathematics and interval expansion principle are adopted to solve the problem with interval parameters. At last, two numerical examples, which include a two-plate coupled system and a single-partition sound-insulation system, are carried out to demonstrate the feasibility and validity of the presented method.
Findings
Interval mathematics and interval expansion principle are adopted to solve the problem with interval parameters.
Originality/value
By integrating the interval analysis, optimization technique and Taylor expansion method, two non-probabilistic, set-theoretical statistical energy analyses are proposed for predicting the dynamical and acoustical response of the complex coupled system with uncertain parameters in high-frequency domain.
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Eiji Nakamachi and Xianghuai Dong
Describes the development of a dynamic‐explicit type finite‐element formulation based on elastic/crystalline‐viscoplastic theory to predict the dynamic forming limits of sheet…
Abstract
Describes the development of a dynamic‐explicit type finite‐element formulation based on elastic/crystalline‐viscoplastic theory to predict the dynamic forming limits of sheet metal. Formulates an evolution equation governing all the slip stages of a single crystal, by modifying Pierce and Bassani’s crystalline plasticity models. Interprets precisely the experimentally observed hardening evolution. Takes account of the importance of the strain rate and temperature sensitivity of the material in predicting dynamic plastic instability. Analyses the deformation and strain localization in a rectangular sheet under stretching, in relation to the plane strain assumption, using the numerical results to demonstrate the influences of tension force and temperature on strain localization, and to show the temperature dependence of shear band formation. Demonstrates that the deviation of tension direction from the axis of symmetry of a single crystal causes non‐simultaneous sliding between primary and conjugate slip systems, resulting in S‐shaped non‐symmetrical deformation.
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Lijuan Shi and Jian Wang
This paper aims to study the reliability of the high-speed train operation control system in the Chinese Train Control System Level 3 (CTCS-3) operating mode.
Abstract
Purpose
This paper aims to study the reliability of the high-speed train operation control system in the Chinese Train Control System Level 3 (CTCS-3) operating mode.
Design/methodology/approach
Dynamic fault tree and Bayesian network method are adopted to analyze the reliability and weakness of the CTCS-3 system.
Findings
First, a physical architecture and data flow diagram of the CTCS-3 system are established according to the typical structure and functions of the CTCS-3 system. Second, the dynamic fault tree of the CTCS-3 system is constructed. Considering the prior probability of the bottom event and the existence of dynamic redundancy, the dynamic fault tree is transformed into a Bayesian net. The reliability of the CTCS-3 system is carried out based on the prior probability and the weakness that affects the reliability of the system based on the posterior probability is also analyzed by the Bayesian network. Finally, it is disclosed that the impact of the on-board subsystem on the reliability of the CTCS-3 system is generally greater than that of the ground subsystem. The two weakest modules in the onboard subsystem are the driver-machine interface (DMI) and balise transmission module (BTM) and the weakest one in the ground subsystem is Balise. The analysis results are generally consistent with the malfunctions in the field operation of China’s high-speed railway.
Originality/value
(1) By reasoning, the reliability of the train operation control system in the CTCS-3 operating mode meets the standard requirements.
(2) Through backward reasoning, it is found that the failure of the onboard subsystem leads to a greater probability of failure of the train control system.
(3) The DMI, BTM and automatic train protection computer unit modules are weak components in the onboard subsystem. Vital digit input&output, train interface unit and train security gateway are rarely involved in previous research, the result in this paper shows that these three modules are also weak components in the subsystem, which requires attention.
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Endang Sylvia and Yos Sunitiyoso
This paper aims to identify all variables and parameters related to business and emission within the petrochemical industry. The variables and parameters specified will be modeled…
Abstract
Purpose
This paper aims to identify all variables and parameters related to business and emission within the petrochemical industry. The variables and parameters specified will be modeled into a system dynamic model that will be a baseline for the proposed best scenario(s) to address the business issue related to emission reduction in the petrochemical industry.
Design/methodology/approach
Literature review and stakeholder interviews were conducted to define the key factors contributing to the emission reduction of the petrochemical industry. The key factors are then developed into a system dynamic model to measure the quantitative impact of changes in those variables on emission and industry profitability.
Findings
This paper provides an analysis of system dynamic model. It suggests that process optimization can lead to a slight amount reduction in emissions. In contrast, a significant reduction shows in the simulation result of bio-based feedstock utilization and implementation of advanced technology. To sustain the emission reduction, strong commitment from stakeholders and support from the government will play an important role.
Research limitations/implications
This research is limited to problem analysis of the primary product (high-value chemical) of the petrochemical industry by only considering the changes in the key factors of emission reduction.
Practical implications
This paper includes implications for interventions that can be imposed to reduce emission while retaining the business profitability.
Originality/value
The contribution of this study is to find the best scenario that can boost emission reduction within Indonesia’s petrochemical industry.
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Stylianos Karatzas, Vasiliki Lazari, Kalliopi Fouseki, Valeria Natalia Pracchi and Evagelos Balaskas
Heritage building management serves as a potent catalyst for sustainability, yet it poses a distinctive set of challenges. Achieving a harmonious balance between conserving the…
Abstract
Purpose
Heritage building management serves as a potent catalyst for sustainability, yet it poses a distinctive set of challenges. Achieving a harmonious balance between conserving the building's historical and cultural value and ensuring modern functionality and safety remains a primary concern. The present work proposes a socio-technical approach to the development and use of a digital twin (DT) that will integrate social data related to the use of heritage buildings with building and environmental data.
Design/methodology/approach
The paper presents a logical and systematic joined-up management framework to the targeted heritage buildings, according to a “Whole Building” approach. Our approach is informed by the underpinning assumption that a heritage building and even more a heritage neighborhood is a socio-technical, complex and dynamic system, the change of which depends on the dynamic interconnections of materials, competences, resources, values, space/environment, senses and time.
Findings
A heritage dynamics approach is adopted to unfold the dynamic nature of heritage and to better inform decisions that can be made in the present and future, achieving people-centered and place-based heritage management. This proposition underlines the heritage transformation as a complex systemic process that consists of nonlinear interconnections of multiple heterogeneous factors (values, senses, attitudes, spaces and resources).
Originality/value
This paper presents a multi-level framework of DTs that interact hierarchically to comprehensively understand, assimilate and seamlessly integrate intricate contexts, even when faced with conflicting conditions from diverse cultural heritage entities. This paper outlines the importance of the iterative system dynamics (SD) approach, which enables adaptive management and ensures the resilience of cultural heritage over time.
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