Juelin Leng, Quan Xu, Tiantian Liu, Yang Yang and Peng Zheng
The purpose of this paper is to present an automatic approach for mesh sizing field generation of complicated computer-aided design (CAD) models.
Abstract
Purpose
The purpose of this paper is to present an automatic approach for mesh sizing field generation of complicated computer-aided design (CAD) models.
Design/methodology/approach
In this paper, the authors present an automatic approach for mesh sizing field generation. First, a source point extraction algorithm is applied to capture curvature and proximity features of CAD models. Second, according to the distribution of feature source points, an octree background mesh is constructed for storing element size value. Third, mesh size value on each node of background mesh is calculated by interpolating the local feature size of the nearby source points, and then, an initial mesh sizing field is obtained. Finally, a theoretically guaranteed smoothing algorithm is developed to restrict the gradient of the mesh sizing field.
Findings
To achieve high performance, the proposed approach has been implemented in multithreaded parallel using OpenMP. Numerical results demonstrate that the proposed approach is remarkably efficient to construct reasonable mesh sizing field for complicated CAD models and applicable for generating geometrically adaptive triangle/tetrahedral meshes. Moreover, since the mesh sizing field is defined on an octree background mesh, high-efficiency query of local size value could be achieved in the following mesh generation procedure.
Originality/value
How to determine a reasonable mesh size for complicated CAD models is often a bottleneck of mesh generation. For the complicated models with thousands or even ten thousands of geometric entities, it is time-consuming to construct an appropriate mesh sizing field for generating high-quality mesh. A parallel algorithm of mesh sizing field generation with low computational complexity is presented in this paper, and its usability and efficiency have been verified.
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Jia Liao, Yun Zhan and Kangbo Liu
This study investigates the impact of customer stability on the cost of debt and the moderating effect of environmental uncertainty on the above relationship.
Abstract
Purpose
This study investigates the impact of customer stability on the cost of debt and the moderating effect of environmental uncertainty on the above relationship.
Design/methodology/approach
An empirical analysis based on the ordinary least squares (OLS) regression model is conducted using China’s A-share listed companies on the Shanghai and Shenzhen Stock Exchanges from 2007 to 2021.
Findings
The results indicate that customer stability significantly inhibits the cost of debt, and the higher the environmental uncertainty, the more significant the inhibitory effect of customer stability on the cost of debt. The results of heterogeneity analyses indicate that the more intense the industry competition, the higher the customer concentration or the older the average customer age, the more significant the inhibiting effect of customer stability on the cost of debt.
Research limitations/implications
This study highlights the importance of customer relationship management and supply chain risk management, which have both theoretical and managerial implications. Despite its contributions, this study has limitations, such as China’s institutional context limits, which the generalisability of our results, and the sample size for this study is small because of limitations in measuring customer stability.
Originality/value
Existing literature has not yet reached a consistent conclusion on how customer relationships affect the cost of debt, and such studies are mainly centered around perspectives such as customer concentration and the contagion effect of supply chains. This study constructs an indicator of customer stability using detailed information on the top five customers of China’s A-share listed companies and dynamically examines the impact of customer stability on the cost of debt, which expands the research on the influencing factors of the cost of debt, the economic consequences of customer stability and the theory of customer relationship management.
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Lisha He, Jianjing Zheng, Yao Zheng, Jianjun Chen, Xuan Zhou and Zhoufang Xiao
The purpose of this paper is to develop parallel algorithms for moving boundary simulations by local remeshing and compose them to a fully parallel simulation cycle for the…
Abstract
Purpose
The purpose of this paper is to develop parallel algorithms for moving boundary simulations by local remeshing and compose them to a fully parallel simulation cycle for the solution of problems with engineering interests.
Design/methodology/approach
The moving boundary problems are solved by unsteady flow computations coupled with six-degrees-of-freedom equations of rigid body motion. Parallel algorithms are developed for both computational fluid dynamics (CFD) solution and grid deformation steps. Meanwhile, a novel approach is developed for the parallelization of the local remeshing step. It inputs a distributed mesh after deformation, then marks low-quality elements to be deleted on the respective processors. After that, a parallel domain decomposition approach is used to repartition the hole mesh and then to redistribute the resulting sub-meshes onto all available processors. Then remesh individual sub-holes in parallel. Finally, the element redistribution is rebalanced.
Findings
If the CFD solver is parallelized while the remaining steps are executed in sequential, the performance bottleneck of such a simulation cycle is observed when the simulation of large-scale problem is executed. The developed parallel simulation cycle, in which all of time-consuming steps have been efficiently parallelized, could overcome these bottlenecks, in terms of both memory consumption and computing efficiency.
Originality/value
A fully parallel approach for moving boundary simulations by local remeshing is developed to solve large-scale problems. In the algorithm level, a novel parallel local remeshing algorithm is present. It repartitions distributed hole elements evenly onto all available processors and ensures the generation of a well-shaped inter-hole boundary always. Therefore, the subsequent remeshing step can fix the inter-hole boundary involves no communications.
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Bowen Zheng, Yarou Wang, Muhammad Abdul Kamal and Assad Ullah
Culture and institutions are among the essential sources of comparative advantage in international trade and may influence a country's FDI influx. This paper aims to analyze the…
Abstract
Purpose
Culture and institutions are among the essential sources of comparative advantage in international trade and may influence a country's FDI influx. This paper aims to analyze the impact of cultural distance (CD) and institutional distance (ID) on the efficiency of China's outward foreign direct investment (OFDI) for the panel of 43 countries during 2003–2016.
Design/methodology/approach
The stochastic frontier approach (SFA) has been incorporated into the standard gravity model of gravity Kalirajan, 1999; Ravishankar and Stack, 2014). SFA has traditionally been implemented to evaluate the production frontier as the highest yield that could possibly be generated from specified input levels. The production process is viewed to be fully efficient if the real output is performed at frontier level. Otherwise, the production process is assumed technically inefficient, which implies potential scope for enhanced output. This error term is split into two parts, a non-negative term and more standard asymmetrical term. The former identifies inefficiencies in production, while the latter retrieves random disorders
Findings
The outcomes assert a U-shaped relationship between CD and the efficiency of China's OFDI. Put differently, when the CD is minimal, the “liability of foreignness” (LOF) effect plays a dominant role; and CD tends to reduce the efficiency of China's OFDI. On the flip side, when the culture distance is greater than a certain threshold level, the “advantages of foreignness” (AOF) effect plays a predominant role, and CD improves the efficiency of China's OFDI. Institutional distance results in the “LOF” effect significantly reduce the efficiency of China's OFDI.
Research limitations/implications
Notwithstanding these contributions, our study has some limitations which offer directions for future research. The major limitation of this research work is the availability of comprehensive data for a well extended time, in particular for the variable of CD. Further, a firm-level study can shed light on the motivations and performance of China OFDI. Finally, given that our analysis focuses on emerging market multinational enterprises (EMNEs) from China, the findings might not be explicitly generalizable to MNEs from other developing countries. Future studies should concentrate on the comparative study of China's OFDI with other developing countries, to deepen our understanding of the effects of ID and CD on the efficiency of OFDI.
Originality/value
(1) The work is novel in nature as the authors attempt to explore the effect of ID and CD on efficiency of Chinese FDI. To the best of the authors’ knowledge, no research is conducted in this direction in terms of Chinese FDI. (2) Further, the prior studies employed standard gravity model, which may not correctly evaluate the trade potential viewed as the highest potential value. To overcome the shortcomings of the standard gravity model in estimation of the trade performance and efficiency, the SFA has been incorporated into the standard gravity model of gravity.
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Nian Zhang, Shuo Zheng, Lingyuan Tian and Guiwu Wei
In the supply chain disruption risk, the issue of supplier evaluation and selection is solved by an extended VIKOR method based on regret theory.
Abstract
Purpose
In the supply chain disruption risk, the issue of supplier evaluation and selection is solved by an extended VIKOR method based on regret theory.
Design/methodology/approach
Considering the influence of irrational emotions of decision makers, an evaluation model is designed by the regret theory and VIKOR method, which makes the decision-making process closer to reality.
Findings
The paper has some innovations in the evaluation index system and evaluation model construction. The method has good stability under the risk of supply chain interruption.
Originality/value
The mixed evaluation information is used to describe the attributes, and the evaluation index system is constructed by the combined method of the social network analysis method and the literature research method to ensure the accuracy and accuracy of the extracted attributes. The issue of supplier evaluation and selection is solved by an extended VIKOR method based on regret theory.
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The purpose of this paper is to eliminate the fluctuations in train arrival and departure times caused by skewed distributions in interval operation times. These fluctuations…
Abstract
Purpose
The purpose of this paper is to eliminate the fluctuations in train arrival and departure times caused by skewed distributions in interval operation times. These fluctuations arise from random origin and process factors during interval operations and can accumulate over multiple intervals. The aim is to enhance the robustness of high-speed rail station arrival and departure track utilization schemes.
Design/methodology/approach
To achieve this objective, the paper simulates actual train operations, incorporating the fluctuations in interval operation times into the utilization of arrival and departure tracks at the station. The Monte Carlo simulation method is adopted to solve this problem. This approach transforms a nonlinear model, which includes constraints from probability distribution functions and is difficult to solve directly, into a linear programming model that is easier to handle. The method then linearly weights two objectives to optimize the solution.
Findings
Through the application of Monte Carlo simulation, the study successfully converts the complex nonlinear model with probability distribution function constraints into a manageable linear programming model. By continuously adjusting the weighting coefficients of the linear objectives, the method is able to optimize the Pareto solution. Notably, this approach does not require extensive scene data to obtain a satisfactory Pareto solution set.
Originality/value
The paper contributes to the field by introducing a novel method for optimizing high-speed rail station arrival and departure track utilization in the presence of fluctuations in interval operation times. The use of Monte Carlo simulation to transform the problem into a tractable linear programming model represents a significant advancement. Furthermore, the method’s ability to produce satisfactory Pareto solutions without relying on extensive data sets adds to its practical value and applicability in real-world scenarios.
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Tiantian Liu, Juelin Leng, Kailong Xu, Quan Xu, Yang Yang and Peng Zheng
Automatic mesh generation is still a challenge problem for combustion fluid dynamics simulations because of the high-quality requirement and complexity of geometries. This paper…
Abstract
Purpose
Automatic mesh generation is still a challenge problem for combustion fluid dynamics simulations because of the high-quality requirement and complexity of geometries. This paper aims to find an efficient automatic analysis model creation and mesh generation method to save the time for pre-processing in numerical simulations.
Design/methodology/approach
Based on the previous work, we explore effective model processing and mesh generation methods from practical engineering applications. Considering the automation and high quality requirement, we construct an automatic mesh generation procedure for combustion fluid dynamics problems.
Findings
The numerical results show that the procedure we proposed in this paper can automatically generate high quality mesh for combustion fluid dynamics simulations. The strategy of fluid model construction is time-saving and with high-precision. The mesh generation method in our procedure is automatic and efficient.
Practical implications
The procedure proposed in this paper is applicable to the practical engineering application model, such as aircraft simulation, aeroengine simulation and so on. The procedure has been integrated into an numerical simulation software.
Originality/value
The method proposed in this paper has very practical application value. It can be used in the practical application and saves a lot of manual processing time for numerical stimulation specialists.
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Enying Li, Zheng Zhou, Hu Wang and Kang Cai
This study aims to suggest and develops a global sensitivity analysis-assisted multi-level sequential optimization method for the heat transfer problem.
Abstract
Purpose
This study aims to suggest and develops a global sensitivity analysis-assisted multi-level sequential optimization method for the heat transfer problem.
Design/methodology/approach
Compared with other surrogate-assisted optimization methods, the distinctive characteristic of the suggested method is to decompose the original problem into several layers according to the global sensitivity index. The optimization starts with the several most important design variables by the support vector regression-based efficient global optimization method. Then, when the optimization process progresses, the filtered design variables should be involved in optimization one by one or the setting value. Therefore, in each layer, the design space should be reduced according to the previous optimization result. To improve the accuracy of the global sensitivity index, a novel global sensitivity analysis method based on the variance-based method incorporating a random sampling high-dimensional model representation is introduced.
Findings
The advantage of this method lies in its capability to solve complicated problems with a limited number of sample points. Moreover, to enhance the reliability of optimum, the support vector regression-based global efficient optimization is used to optimize in each layer.
Practical implications
The developed optimization tool is built by MATLAB and can be integrated by commercial software, such as ABAQUS and COMSOL. Lastly, this tool is integrated with COMSOL and applied to the plant-fin heat sink design. Compared with the initial temperature, the temperature after design is over 49°. Moreover, the relationships among all design variables are also disclosed clearly.
Originality/value
The D-MORPH-HDMR is integrated to obtain the coupling relativities among the design variables efficiently. The suggested method can be decomposed into multiplier layers according to the GSI. The SVR-EGO is used to optimize the sub-problem because of its robustness of modeling.
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Leven J. Zheng, Nazrul Islam, Justin Zuopeng Zhang, Huan Wang and Kai Ming Alan Au
This study seeks to explore the intricate relationship among supply chain transparency, digitalization and idiosyncratic risk, with a specific focus on newly public firms. The…
Abstract
Purpose
This study seeks to explore the intricate relationship among supply chain transparency, digitalization and idiosyncratic risk, with a specific focus on newly public firms. The objective is to determine whether supply chain transparency effectively mitigates idiosyncratic risk within this context and to understand the potential impact of digitalization on this dynamic interplay.
Design/methodology/approach
The study utilizes data from Initial Public Offerings (IPOs) on China’s Growth Enterprise Board (ChiNext) over the last five years, sourced from the CSMAR database and firms’ annual reports. The research covers the period from 2009 to 2021, observing each firm for five years post-IPO. The final sample comprises 2,645 observations from 529 firms. The analysis employs the Hausman test, considering the panel-data structure of the sample and favoring fixed effects over random effects. Additionally, it applies the high-dimensional fixed effects (HDFE) estimator to address unobserved heterogeneity.
Findings
The analysis initially uncovered an inverted U-shaped relationship between supply chain transparency and idiosyncratic risk, indicating a delicate equilibrium where detrimental effects diminish and beneficial effects accelerate with increased transparency. Moreover, this inverted U-shaped relationship was notably more pronounced in newly public firms with a heightened level of firm digitalization. This observation implies that firm digitalization amplifies the impact of transparency on a firm’s idiosyncratic risk.
Originality/value
This study distinguishes itself by providing distinctive insights into supply chain transparency and idiosyncratic risk. Initially, we introduce and substantiate an inverted U-shaped correlation between supply chain transparency and idiosyncratic risk, challenging the conventional linear perspective. Secondly, we pioneer the connection between supply chain transparency and idiosyncratic risk, especially for newly public firms, thereby enhancing comprehension of financial implications. Lastly, we pinpoint crucial digital conditions that influence the relationship between supply chain transparency and idiosyncratic risk management, offering a nuanced perspective on the role of technology in risk management.