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1 – 10 of over 96000Marcelo Santiago Sousa, Pedro Paglione, Roberto Gil Annes Silva, Flavio Luiz Cardoso-Ribeiro and Sebastião Simões Cunha
The purpose of this paper is to present a mathematical model of one very flexible transport category airplane whose structural dynamics was modeled with the strain-based…
Abstract
Purpose
The purpose of this paper is to present a mathematical model of one very flexible transport category airplane whose structural dynamics was modeled with the strain-based formulation. This model can be used for the analysis of couplings between the flight dynamics and structural dynamics.
Design/methodology/approach
The model was developed with the use of Hamiltonian mechanics and strain-based formulation. Nonlinear flight dynamics, nonlinear structural dynamics and inertial couplings are considered.
Findings
The mathematical model allows the analysis of effects of high structural deformations on airplane flight dynamics.
Research limitations/implications
The mathematical model has more than 60 degrees of freedom. The computational burden is too high, if compared to the traditional rigid body flight dynamics simulations.
Practical implications
The mathematical model presented in this work allows a detailed analysis of the couplings between flight dynamics and structural dynamics in very flexible airplanes. The better comprehension of these couplings will contribute to the development of flexible airplanes.
Originality/value
This work presents the application of nonlinear flight dynamics-nonlinear structural dynamics-strain-based formulation (NFNS_s) methodology to model the flight dynamics of one very flexible transport category airplane. This paper addresses also the way as the analysis of results obtained in nonlinear simulations can be made. Comparisons of the NFNS_s and nonlinear flight dynamics-linear structural dynamics methodologies are presented in this work.
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The three-sector framework (relating to agriculture, manufacturing and services) is one of the major concepts for studying the long-run change of the economic structure. This…
Abstract
Purpose
The three-sector framework (relating to agriculture, manufacturing and services) is one of the major concepts for studying the long-run change of the economic structure. This paper aims to discuss the system-theoretical classification of the structural change in the three-sector framework and, in particular, its predictability by the Poincaré–Bendixson theory.
Design/methodology/approach
This study compares the assumptions of the Poincaré–Bendixson theory to the typical axioms of structural change modeling, the empirical evidence on the geometrical properties of structural change trajectories and the methodological arguments referring to the laws of structural change.
Findings
The findings support the assumption that the structural change phenomenon is representable by a dynamical system that is predictable by the Poincaré–Bendixson theory. This result implies, among others, that in the long run, structural change is either transitory or cyclical and can be used in further geometrical/topological long-run structural change modeling and prediction.
Originality/value
Although widespread in mathematics, geometrical/topological modeling methods have not been used in modeling and prediction of long-run structural change, despite the fact that they seem to be predestined for this purpose owing to their global, system-theoretical nature, allowing for a reduction of ideology content of predictions and greater robustness of results.
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Xuanya Shi, Francis Boadu and Yifei Du
Both the scope of postentry growth and the scale of postentry growth are essential for Chinese multinational enterprises' aggressive internationalization. Yet, prior literature…
Abstract
Purpose
Both the scope of postentry growth and the scale of postentry growth are essential for Chinese multinational enterprises' aggressive internationalization. Yet, prior literature has not considered the synergistic approach of postentry growth that seeks the scope of growth and the scale of growth simultaneously. Building upon the embeddedness perspective and the learning view, we address how structural embeddedness directly affects firms' postentry growth in the form of scope and scale and indirectly affects postentry growth via both the scope of growth and the scale of growth. Particularly, we investigate the decreasing mediating effect of the growth's scale on the growth's scope when embeddedness strengthens.
Design/methodology/approach
With a survey data set of 206 Chinese multinational firms from manufacturing and service industries, we conduct structural equation modeling (SEM), partial least squares path modeling (PLS-PM), instantaneous indirect effect assessment and hierarchical linear regression model to test our hypotheses.
Findings
First, Chinese multinational enterprises’ (CMNEs) structural embeddedness is positively related to their scope of postentry growth, while has a U-shaped relationship with their scale of postentry growth. Second, CMNEs' scope of postentry growth mediates the relationship between structural embeddedness and the scale of postentry growth, the mediation effect counts for 33.5% of the over effect. Finally, the indirect effect of structural embeddedness on the scope of postentry growth through the scale of postentry growth is nonlinear. As the structural embeddedness strengthens, the positive indirect effect gradually weakens.
Originality/value
We believe this study further connects core international business research on postentry growth to the fast-growing literature on emerging markets multinational enterprises' internationalization. In addition, we undertake an initial effort in addressing an important gap in the literature: how structural embeddedness matters to firms' postentry growth. Moreover, this study finds important evidence to support the direct and indirect effect of structural embeddedness on postentry growth.
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Ranjit Kumar Chaudhary, Tathagata Roy and Vasant Matsagar
Despite recognizing the significance of risk-based frameworks in fire safety engineering, the usual approach in structural fire design is largely member/component level, wherein…
Abstract
Purpose
Despite recognizing the significance of risk-based frameworks in fire safety engineering, the usual approach in structural fire design is largely member/component level, wherein effect of uncertainties influencing the fire resistance of structures are not explicitly considered. In this context, a probabilistic framework is presented to investigate the vulnerability of a reinforced concrete (RC) members and structure under fire loading scenario.
Design/methodology/approach
The RC structures exposed to fire are modeled in a finite element (FE) platform incorporating material and geometric nonlinearity, in which the transient thermo-mechanical analysis is carried out by suitably incorporating the temperature variation of thermal and mechanical properties of both concrete and steel rebar. The stochasticity in the system is considered in structural resistance, thermal and fire model parameters, and the subsequent fragility curves are developed considering threshold limit state of deflection.
Findings
The fire resistance of RC structure is reported to be significantly lower in comparison to the RC members, thereby illustrating the current prescriptive design approaches based on studies of structural member behavior to be crucial from a safety and reliability point of view.
Practical implications
The framework developed for the vulnerability assessment of RC structures under fire hazard through FE analysis can be effectively used to estimate the structural fire resistance for other similar structure to enhance safety and reliability of structures under such extreme threats.
Originality/value
The paper proposes a novel methodology for vulnerability assessment of three-dimensional RC structures under fire hazard through FE analysis and provides comparison of the structural fragility with fragility developed for structural members. Moreover, the research emphasizes to assume 3D behavior of the structure rather than the approximate 2D behavior.
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Zefeng Xiao, Yongqiang Yang, Di Wang, Changhui Song and Yuchao Bai
This paper aims to summarize design rules based on the process characteristics of selective laser melting (SLM) and structural optimization and apply the design rules in the…
Abstract
Purpose
This paper aims to summarize design rules based on the process characteristics of selective laser melting (SLM) and structural optimization and apply the design rules in the lightweight design of an aluminum alloy antenna bracket. The design goal is to reduce 30 per cent of the weight while maintaining the stress levels in the original part.
Design/methodology/approach
To reduce weight as much as possible, the titanium alloy with higher specific strength was selected during the process of optimization. The material distribution of the bracket was improved by the topology optimization design. The redesign for SLM was used to obtain an optimization model, which was more suitable for SLM. The component performance was improved by shape optimization. The modal analysis data of the structural optimization model were compared with those of the stochastic lightweight model to verify the structural optimization model. The scanning data were compared with those of the original model to verify whether the model was suitable for SLM.
Findings
Structural optimization design for antenna bracket realized the mass decrease of 30.43 per cent and the fundamental frequency increase of 50.18 per cent. The modal analysis data of the stochastic lightweight model and the structural optimization model indicated that the optimization performance of structural optimization method was better than that of the stochastic lightweight method. The comparison results between the scanning data of the forming part and the original data confirmed that the structural optimization design for SLM lightweight component could achieve the desired forming accuracy.
Originality/value
This paper summarizes geometric constraints in SLM and derives design rules of structural optimization based on the process characteristics of SLM. SLM design rules make structural optimization design more reasonable. The combination of structural optimization design and SLM can improve the performance of lightweight antenna bracket significantly.
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Siu Loon Hoe and Steven McShane
The topic of organizational learning is populated with many theories and models; many relate to the enduring organizational learning framework consisting of knowledge acquisition…
Abstract
Purpose
The topic of organizational learning is populated with many theories and models; many relate to the enduring organizational learning framework consisting of knowledge acquisition, knowledge dissemination, and knowledge use. However, most of the research either emphasizes structural knowledge acquisition and dissemination as a composite construct, or focuses solely on the structural aspect of knowledge acquisition and dissemination. The primary objective of this study is to develop and test a model of organizational learning that incorporates both structural and informal knowledge acquisition and dissemination and as separate processes. The predictors of these processes are also proposed
Design/methodology/approach
A model of organizational learning that incorporates both structural and informal knowledge acquisition and dissemination constructs, along with three predictors of these organizational learning constructs were developed and quantitatively tested.
Findings
An inference to the research questions and hypotheses suggests that informal knowledge acquisition and dissemination have significant paths to market knowledge use, whereas structural knowledge acquisition and dissemination have, at best, a weak association with market knowledge use. Although the results were based on exploratory analysis, they provide tentative quantitative evidence that informal knowledge processes are at least as important as structural knowledge processes in market‐based organizational learning.
Originality/value
While the hypothesized model did not satisfy the goodness‐of‐fit tests, data‐driven exploratory analysis helped to refine two separate structural and informal models for future testing. The statistical explanation provided and procedures used to remedy the non‐fit issues should help future researchers to deal with structural equation‐modeling issues when similar non‐fit problems arise.
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Describes research which continues the quest to model performanceusing structural equation models. The objective is to provide meaningfuland substantively interpretable…
Abstract
Describes research which continues the quest to model performance using structural equation models. The objective is to provide meaningful and substantively interpretable predictions of process performance using structural equation modelling. Develops structural equation models which clearly define the performance relationships for a backroom bank card remittance process using criteria such as process quality errors, employee turnover rates, labour productivity, on‐time delivery, and unit cost. Also defines the idea of a process quality equilibrium point (error rate) using structural equation modelling, and investigates how to use these structural equation models to help set internal and external standards of performance.
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Ben Ruben R., S. Vinodh and Asokan P.
The study aims to describe the development of a structural measurement model using structural equation modeling technique to validate the association that exists between Lean Six…
Abstract
Purpose
The study aims to describe the development of a structural measurement model using structural equation modeling technique to validate the association that exists between Lean Six Sigma (LSS) and sustainable manufacturing strategies.
Design/methodology/approach
Both LSS and sustainable manufacturing aim at improving the firm’s business competitiveness which forms a strategic link that benefits the manufacturing organizations. The study aims to investigate the relationship among constructs that leads to operational excellence while deploying LSS and sustainable manufacturing strategies in organizations.
Findings
Empirical data needed for the study are collected from experts belonging to various industries that are implementing both LSS and sustainable manufacturing practices. Later statistical estimates (hypotheses) are being formulated to confirm the developed measurement model. Based on the obtained results after analysis of the structural model, the statistical estimate is either being accepted or rejected. Results of this study reveal that there exists a strong correlation between LSS and sustainable manufacturing factors that leads to organizational performance.
Research limitations/implications
Additional indicators could be included to deal with technological advancements in sustainable manufacturing.
Practical implications
The study has been done with regard to Indian automotive component manufacturing organizations scenario. Hence, the inferences derived have practical relevance.
Originality/value
The development of structural model for the Lean Six Sigma system with sustainability considerations is the original contribution of the authors.
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Tofigh Hamidavi, Sepehr Abrishami, Pasquale Ponterosso, David Begg and Nikos Nanos
The paper aims to leverage the importance of the integrated automatic structural design for tall buildings at the early stage. It proposes to use an automatic prototype to perform…
Abstract
Purpose
The paper aims to leverage the importance of the integrated automatic structural design for tall buildings at the early stage. It proposes to use an automatic prototype to perform the structural design, analysis and optimisation in a building information modelling (BIM)-based platform. This process starts with extracting the required information from the architectural model in Revit Autodesk, such as boundary conditions and designs different options of the structural models in Robot Autodesk. In this process, Dynamo for Revit is used to define the mathematical functions to use different variables and generate various structural models. The paper aims to expand the domain of automation in the BIM platform to reduce the iterative process in different areas such as conceptual structural design and collaboration between architects and structural engineers to reduce the time and cost at the early stages.
Design/methodology/approach
The paper begins with an exploratory research by adopting a qualitative methodology and using open-ended questions to achieve more information about the phenomenon of automation and interoperability between structural engineers and architects and gain new insight into this area. Furthermore, correlation research is used by adopting quantitative and short questions to compare the proposed prototype with the traditional process of the structural design and optimisation and the interoperability between architects and engineers and consequently, validate the research.
Findings
As an outcome of the research, a structural design optimisation (SDO) prototype was developed to semi-automate the structural design process of tall buildings at the early stages. Moreover, the proposed prototype can be used during the early stage of structural design in different areas such as residential buildings, bridges, truss, reinforced concrete detailing, etc. Moreover, comprehensive literature regarding using automation in structural design, optimisation process and interoperability between architects and engineers is conducted that provides a new insight to contribute to future research and development.
Research limitations/implications
Due to the time limit, the paper results may lack in a comprehensive automatic structural design process. Therefore, the researchers are encouraged to expand the workability of the prototype for a comprehensive automatic design check such as automatic design for the minimum deflection, displacement of different types of buildings.
Practical implications
The prototype includes implications for the development of different automatic designs.
Originality/value
The focus of this paper is the optimisation of the structural design in the BIM platform by using automation. This combination is one of the novelties of this paper, and the existing literature has a very limited amount of information and similar work in this area, especially interoperability between architects and engineers.
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Anupam Dutta, Naji Jalkh, Elie Bouri and Probal Dutta
The purpose of this paper is to examine the impact of structural breaks on the conditional variance of carbon emission allowance prices.
Abstract
Purpose
The purpose of this paper is to examine the impact of structural breaks on the conditional variance of carbon emission allowance prices.
Design/methodology/approach
The authors employ the symmetric GARCH model, and two asymmetric models, namely the exponential GARCH and the threshold GARCH.
Findings
The authors show that the forecast performance of GARCH models improves after accounting for potential structural changes. Importantly, we observe a significant drop in the volatility persistence of emission prices. In addition, the effects of positive and negative shocks on carbon market volatility increase when breaks are taken into account. Overall, the findings reveal that when structural breaks are ignored in the emission price risk, the volatility persistence is overestimated and the news impact is underestimated.
Originality/value
The authors are the first to examine how the conditional variance of carbon emission allowance prices reacts to structural breaks.
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