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1 – 10 of over 24000In this paper, Sensitivity Method (SM) was used to the identification of boundary conditions. Particular attention in this paper was paid to the Levenberg‐Marquardt (L‐M…
Abstract
In this paper, Sensitivity Method (SM) was used to the identification of boundary conditions. Particular attention in this paper was paid to the Levenberg‐Marquardt (L‐M) regularization method, because the inverse problems of the electromagnetic field are not well conditioned in typical cases. It was proved that using some information about the expected solution, the L‐M regularization method gives satisfactory results even in such cases where the singular value analysis (SVA) fails. The identified boundary conditions were compared with the results obtained by using the direct least squares (LS) method.
Chunyun Zhang, Jie Mei, Yushuai Bai, Miao Cui, Haifeng Peng and X. W. Gao
The purpose of this study is to simultaneously determine the constitutive parameters and boundary conditions by solving inverse mechanical problems of power hardening…
Abstract
Purpose
The purpose of this study is to simultaneously determine the constitutive parameters and boundary conditions by solving inverse mechanical problems of power hardening elastoplastic materials in three-dimensional geometries.
Design/methodology/approach
The power hardening elastoplastic problem is solved by the complex variable finite element method in software ABAQUS, based on a three-dimensional complex stress element using user-defined element subroutine. The complex-variable-differentiation method is introduced and used to accurately calculate the sensitivity coefficients in the multiple parameters identification method, and the Levenberg–Marquardt algorithm is applied to carry out the inversion.
Findings
Numerical results indicate that the complex variable finite element method has good performance for solving elastoplastic problems of three-dimensional geometries. The inversion method is effective and accurate for simultaneously identifying multi-parameters of power hardening elastoplastic problems in three-dimensional geometries, which could be employed for solving inverse elastoplastic problems in engineering applications.
Originality/value
The constitutive parameters and boundary conditions are simultaneously identified for power hardening elastoplastic problems in three-dimensional geometries, which is much challenging in practical applications. The numerical results show that the inversion method has high accuracy, good stability, and fast convergence speed.
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Haolong Chen, Zhibo Du, Xiang Li, Huanlin Zhou and Zhanli Liu
The purpose of this paper is to develop a transform method and a deep learning model to identify the inner surface shape based on the measurement temperature at the outer boundary…
Abstract
Purpose
The purpose of this paper is to develop a transform method and a deep learning model to identify the inner surface shape based on the measurement temperature at the outer boundary of the pipe.
Design/methodology/approach
The training process is assisted by the finite element method (FEM) simulation which solves the direct problem for the data preparation. To avoid re-meshing the domain when the inner surface shape varies, a new transform method is proposed to transform the shape identification problem into the effective thermal conductivity identification problem. The deep learning model is established to set up the relationship between the measurement temperature and the effective thermal conductivity. Then the unknown geometry shape is acquired by the mapping between the inner shape and the effective thermal conductivity through the inverse transform method.
Findings
The new method is successfully applied to identify the internal boundary of a pipe with eccentric circle, ellipse and nephroid inner geometries. The results show that as the measurement points increased and the measurement error decreased, the results became more accurate. The position of the measurement point and mesh density of the FEM model have less effect on the results.
Originality/value
The deep learning model and the transform method are developed to identify the pipe inner surface shape. There is no need to re-mesh the domain during the computation progress. The results show that the proposed method is a fast and an accurate tool for identifying the pipe inner surface.
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The purpose of this paper is to investigate the relationship of leader aggressive humor on employee extra-role behaviors of proactivity and creativity by probing feeling…
Abstract
Purpose
The purpose of this paper is to investigate the relationship of leader aggressive humor on employee extra-role behaviors of proactivity and creativity by probing feeling ostracized as a mediator and team identification and professional identification as boundary conditions.
Design/methodology/approach
A survey sample of 347 employees was collected from three technology companies in Sichuan and Guizhou, China. Hierarchical regression analysis and PROCESS macro in SPSS were used to test the hypotheses.
Findings
The results indicate that leader aggressive humor is negatively related to employee extra-role behaviors. Feeling ostracized is an important mechanism linking leader aggressive humor and employee extra-role behaviors and team identification and professional identification moderate the relationship.
Practical implications
Organizations should make rules to prevent leaders from using aggressive humorous behaviors and encourage coworkers to show more affiliative funny behaviors during breaks to reduce employees' sense of ostracism.
Originality/value
Building on sociometer theory, this research demonstrates the opposite moderating effects of team identification and professional identification in the effects of leader aggressive humor on feeling ostracized and consequently employee extra-role behaviors.
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This paper aims at showing that the finite element method is the most important numerical tool to analyse bio‐solids or bio‐fluids because of the constitutive complexity and…
Abstract
This paper aims at showing that the finite element method is the most important numerical tool to analyse bio‐solids or bio‐fluids because of the constitutive complexity and unusual clinical input data and requirements involved. These features are absolutely mandatory and modify the mentality of an expert of FEM when he wants to contribute really to the progress of medical practice in their several forms, from biological basis to the surgical assistance. In this context, a clear view of the hierarchic importance of the phenomena involved is necessary to reply correctly to medical operators and to choose the right level of scale. While a scholarly culture of FEM and relative developments have to appeal the attention of biomedical engineers, at the same time their attention mainly is focused on the problem to solve, which must be validated clinically and experimentally. So while convergence remain a typical goal of the analyst, accuracy must be compared with the medical sensitivity. To do this, some physical conditions, less important in other application fields, as the boundary conditions, must be modelled in order to avoid that any model refinement gives unappreciable precision while tends to disregard what a clinician or a surgeon is able to understand and to use in the context of his professional practice. Setting up correct boundary conditions is an emblematic topic because it concerns a typical approach of computational methods applied to biomedical engineering which must consider two separate scale into analysis or a design approach. When a district of the body is to be analysed, the main goal should be to define correctly the subdomain that the district represents with respect to the whole and then to analyse other subdomains inside, at a level more and more micro, as into a system of Chinese boxes. When a medical device is to be designed a systemic view must be acquired. In this paper, we will start from this underlying feature concerning just FEM applications of a knee design carried out by the research staff of the Laboratory of Biological Structure Mechanics. Then other uses of FEM will be described as analysis fragments through problems studied by the authors and referenced in bibliography.
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Peyman Mayeli and Mehdi Nikfar
The present study aims to perform inverse analysis of a conjugate heat transfer problem including conduction and forced convection via the quasi-Newton method. The inverse…
Abstract
Purpose
The present study aims to perform inverse analysis of a conjugate heat transfer problem including conduction and forced convection via the quasi-Newton method. The inverse analysis is defined for a heat source that is surrounded by a solid medium which is exposed to a free stream in external flow.
Design/methodology/approach
The objective of the inverse design problem is finding temperature distribution of the heat source as thermal boundary condition to establish a prescribed temperature along the interface of solid body and fluid. This problem is a simplified version of thermal-based ice protection systems in which the formation of ice is avoided by maintaining the interface of fluid and solid at a specified temperature.
Findings
The effects of the different pertinent parameters such as Reynolds number, interface temperature and thermal conductivity ratio of fluid and solid mediums are analyzed.
Originality/value
This paper fulfils the analysis to study how thermal based anti-icing system can be used with different heat source shapes.
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This paper aims to build on research on the art infusion effect (Hagtvedt and Patrick, 2008a). It investigates the effect of using fine art in advertising and addresses additional…
Abstract
Purpose
This paper aims to build on research on the art infusion effect (Hagtvedt and Patrick, 2008a). It investigates the effect of using fine art in advertising and addresses additional factors that have not been assessed to understand and describe the process of art infusion more thoroughly. Thereby, the moderating role of the art interest of individuals and its interplay with the hedonic value of the product is studied. Effects on attitude and willingness to pay are revealed and the perceived value for money as a further mediating variable that drives the art infusion effect under some conditions is investigated. Moreover, the study examines the effect of the artwork’s familiarity.
Design/methodology/approach
The experimental study follows a 3 (ad picture: photo, unknown painting, well-known painting) × 2 (art interest: low, high) × 2 (product type: highly hedonic, moderately hedonic) between-subjects-design. In total, 447 consumers were surveyed in museums, art exhibitions and neutral public spaces.
Findings
For a clearly hedonic product, the art infusion effect is independent of consumers’ art interest. For an only moderately hedonic and more ambiguous product, this effect only occurs for highly art interested individuals. Moreover, different mediating processes are revealed for these two product types in a moderated mediation model. An effect of familiarity cannot be verified.
Originality/value
Research on effects of art on consumer responses to brands and products is still very limited. In addition to existing research, this paper adds to the identification of boundary conditions and the explanation of drivers of the art infusion effect. Moreover, this is the first study that provides insights on how an artwork affects consumers’ willingness to pay.
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Andrzej Frąckowiak, David Spura, Uwe Gampe and Michał Ciałkowski
T-shaped cavities occur by design in many technical applications. An example of such a stator cavity is the side space between the guide vane carriers and the outer casing of a…
Abstract
Purpose
T-shaped cavities occur by design in many technical applications. An example of such a stator cavity is the side space between the guide vane carriers and the outer casing of a steam turbine. Thermal conditions inside it have a significant impact on the deformation of the turbine casing. In order to improve its prediction, the purpose of this paper is to provide a methodology to gain better knowledge of the local heat transfer at the cavity boundaries based on experimental results.
Design/methodology/approach
To determine the heat transfer coefficient distribution inside a model cavity with the help of a scaled generic test rig, an inverse heat conduction problem is posed and a method for solving such type of problems in the form of linear combinations of Trefftz functions is presented.
Findings
The results of the calculations are compared with another inverse method using first-order gradient optimization technique as well as with estimated values obtained with an analytic two-dimensional thermal network model, and they show an excellent agreement. The calculation procedure is proved to be numerically stable for different degrees of complexity of the sought boundary conditions.
Originality/value
This paper provides a universal and robust methodology for the fast direct determination of an arbitrary distribution of heat transfer coefficients based on material temperature measurements spread over the confining wall.
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Neta A. Moye and Claus W. Langfred
We investigated the role of task and relationship conflict as mediators of the relationship between information sharing and group performance. We suggest that, in addition to the…
Abstract
We investigated the role of task and relationship conflict as mediators of the relationship between information sharing and group performance. We suggest that, in addition to the commonly studied effect of conflict on information sharing, the reverse causal direction is theoretically likely and relevant in today's business climate. Specifically, we hypothesize that information sharing will reduce both task and relationship conflict with beneficial effects on team performance in established groups. We also explore boundary conditions to these conflict‐reducing effects of information sharing, suggesting that the lower a group's task interdependence, the more information sharing reduces task conflict, and the lower a group's average general mental ability, the more information sharing reduces relationship conflict. Analysis of data from 38 groups supported our expectations, revealing the expected negative relationships between information sharing and both task and relationship conflict, as well as the expected moderating effects of task interdependence and general mental ability.
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Wen Li, Bin Guo and Gangxiang Xu
Based on the linkage-leverage-learning (LLL) framework developed by Mathews (2006), the purpose of this paper is to examine how linking, leveraging and learning capabilities…
Abstract
Purpose
Based on the linkage-leverage-learning (LLL) framework developed by Mathews (2006), the purpose of this paper is to examine how linking, leveraging and learning capabilities influence the choice of foreign-entry mode, and the way such influences are contingent on context factors in the emerging markets.
Design/methodology/approach
Contrary to a prior literature applying the LLL framework, which mainly used case studies, this paper adopts a quantitative approach and is based on a sample of 321 Chinese listed companies to test the hypotheses.
Findings
The results show that multinational firms from emerging markets (EMFs) with stronger LLL capabilities are more likely to choose the wholly owned mode in foreign entries. In addition, the relationship between linking capability and wholly owned entry mode choice is weaker at higher levels of cultural distance between home and host country. At the same time, the relationship between learning capability and wholly owned entry mode choice is weaker at higher levels of cultural distance between home and host country, and of institutional distance between prior entries and the focal entry.
Research limitations/implications
An entry mode strategy for firms without ownership advantages and the identification of boundary conditions for applying different LLL capabilities are recommended. The generalizability of the findings from a single-country setting still needs further validation with other emerging economies.
Originality/value
This paper treats internationalization of firms from emerging countries with a different perspective. The underlying idea in this study is that internationalization is not only a process for EMFs to utilize externally accessible assets abroad, but also a process of simultaneously combining internationalization with experiential learning and capability utilization in overseas markets. In addition, the authors also contribute to the literature by providing strong empirical evidence for validating the LLL model and extending the existing entry mode studies.
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