Search results

This article aims to present a direct solution to handle linear constraints in finite element (FE) analysis without penalties or the Lagrange multipliers introduced.

First, the system of linear equations corresponding to the linear constraints is solved for the leading variables in terms of the free variables and the constants. Then, the reduced system of equilibrium equations with respect to the free variables is derived from the finite-dimensional virtual work equation. Finally, the algorithm is designed.

The proposed procedure is promising in three typical cases: (1) to enforce displacement constraints in any direction; (2) to implement local refinements by allowing hanging nodes from element subdivision and (3) to treat non-matching grids of distinct parts of the problem domain. The procedure is general and suitable for 3D non-linear analyses.

The algorithm is fitted only to the Galerkin-based numerical methods.

The proposed procedure does not need Lagrange multipliers or penalties. The tangential stiffness matrix of the reduced system of equilibrium equations reserves positive definiteness and symmetry. Besides, many contemporary Galerkin-based numerical methods need to tackle the enforcement of the essential conditions, whose weak forms reduce to linear constraints. As a result, the proposed procedure is quite promising.

The carbon complementary supply chain (CCSC) is a collaborative framework that facilitates internal carbon credit trading agreements among supply chain agents in compliance with prevailing carbon regulations. Such agreements are highly beneficial, prompting agents to consider joint investment in emission reduction initiatives. However, capital investments come with inevitable opportunity costs, compelling agents to weigh the potential revenue from collaborative investments against these costs. Thus, this paper mainly explores carbon abatement strategies and operational decisions of the CCSC members and the influence of opportunity costs on the strategic choice of cooperative and noncooperative investment.

The authors propose a novel biform game-based theoretical framework that captures the interplay of pricing competition and investment cooperation among CCSC agents and assesses the impact of opportunity costs on CCSC profits and social welfare. Besides, the authors also compare the biform game-based collaborative scenario (Model B) to the noncooperative investment scenario (Model N) to investigate the conditions under which collaborative investment is most effective.

The biform game-based collaborative investment strategy enhances the economic performance of the traditional energy manufacturer, who bears the risk of opportunity costs, as well as the retailer. Additionally, it incentivizes the renewable energy manufacturer to improve environmental performance through renewable projects.

This research contributes significantly by establishing a theoretical framework that integrates the concepts of opportunity costs and biform game theory, offering new insights into the strategic management of carbon emissions within supply chains.

Over the years, dark tourism as a theory has become very heterogenous. It has come to mean a lot of different things, according to the vantage points chosen for analysis. The purpose of this chapter is to provide an overview of the research that has been conducted on the topic of dark tourism including what the accepted definitions are, where it originated from, subcategories of the topic, and tourist motivations for visiting such sites. A discussion regarding the role of cultural differences in perceiving the phenomenon of dark tourism is also included. Dark tourist experience is qualitatively different from that of the leisure tourists, and the theories and frameworks available in the extant tourism literature to understand leisure tourism are insufficient to capture its essence. This means, more foundational conceptualisations and radical theory building are called for – rather than incrementally tweaking the existing ones.

This study aims to research the large cross-section tunnel stability evaluation method corrected after considering the thickness-span ratio.

First, taking the Liuyuan Tunnel of Huanggang-Huangmei High-Speed Railway as an example and taking deflection of the third principal stress of the surrounding rock at a vault after tunnel excavation as the criterion, the critical buried depth of the large section tunnel was determined. Then, the strength reduction method was employed to calculate the tunnel safety factor under different rock classes and thickness-span ratios, and mathematical statistics was conducted to identify the relationships of the tunnel safety factor with the thickness-span ratio and the basic quality (BQ) index of the rock for different rock classes. Finally, the influences of thickness-span ratio, groundwater, initial stress of rock and structural attitude factors were considered to obtain the corrected BQ, based on which the stability of a large cross-section tunnel with a depth of more than 100 m during mechanized operation was analyzed. This evaluation method was then applied to Liuyuan Tunnel and Cimushan No. 2 Tunnel of Chongqing Urban Expressway for verification.

This study shows that under different rock classes, the tunnel safety factor is a strict power function of the thickness-span ratio, while a linear function of the BQ to some extent. It is more suitable to use the corrected BQ as a quantitative index to evaluate tunnel stability according to the actual conditions of the site.

The existing industry standards do not consider the influence of buried depth and span in the evaluation of tunnel stability. The stability evaluation method of large section tunnel considering the correction of overburden span ratio proposed in this paper achieves higher accuracy for the stability evaluation of surrounding rock in a full or large-section mechanized excavation of double line high-speed railway tunnels.

The paper aims to propose an assembly scheme based on master–slave coordination for a compliant dual-arm robot to complete a peg-in-hole assembly task.

The proposed assembly scheme is inspired by the coordinated behaviors of human beings in the assembly process. The left arm and right arm of the robot are controlled to move alternately. The fixed arm and the moving arm are distinguished as the slave arm and the master arm, respectively. The position control model is used at the uncontacted stage, and the torque control model is used at the contacted stage.

The proposed assembly scheme is evaluated through peg-in-hole assembly experiments with different shapes of assembly piece. The round, triangle and square assembly piece with 0.5 mm maximum clearance between the peg and the hole can be assembled successfully based on the proposed method. Furthermore, three assembly strategies are investigated and compared in the peg-in-hole assembly experiments with different shapes of assembly piece.

The contribution of this study is that the authors propose an assembly scheme for a compliant dual-arm robot to overcome the low positioning accuracy and complete the peg-in-hole assembly tasks with different shapes parts.

This paper aims to assess the feasibility of additively manufactured wind tunnel models. The additively manufactured model was used to validate a computational framework allowing the evaluation of the performance of five wing models.

An optimized fighter wing was additively manufactured and tested in a low-speed wind tunnel to obtain the aerodynamic coefficients and deflections at different speeds and angles of attack. The flexible wing model with optimized curvilinear spars and ribs was used to validate a finite element framework that was used to study the aeroelastic performance of five wing models. As a computationally efficient optimization method, homogenization-based topology optimization was used to generate four different lattice internal structures for the wing in this study. The efficiency of the spline-based optimization used for the spar-rib model and the lattice-based optimization used for the other four wings were compared.

The aerodynamic loads and displacements obtained experimentally and computationally were in good agreement, proving that additive manufacture can be used to create complex accurate models. The study also shows the efficiency of the homogenization-based topology optimization framework in generating designs with superior stiffness.

To the best of the authors’ knowledge, this is the first time a wing model with curvilinear spars and ribs was additively manufactured as a single piece and tested in a wind tunnel. This research also demonstrates the efficiency of homogenization-based topology optimization in generating enhanced models of different complexity.

Based on the conservation of resource theory, this paper explores the impact of differentiated transformational leadership on employees' taking charge in the context of Chinese organizations, with psychological availability as a mediator and collectivism orientation as a moderator.

The authors distributed paired questionnaires to 67 team managers and 219 team members to obtain research data and established a hierarchical linear model for the hypothesis testing.

The results show that team-focus transformational leadership has a significant positive impact on employees' taking charge, and individual-focus transformational leadership has a significant negative impact on employees' taking charge. Specifically, psychological availability plays a partial mediating role between differentiated transformational leadership and employees' taking charge. Moreover, collectivism orientation has no significant moderating effect between team-focus transformational leadership and psychological availability. But it has a significant moderating effect between individual-focus transformational leadership and psychological availability, i.e. the higher the level of collectivism orientation, the stronger the negative effect of individual-focus transformational leadership on psychological availability.

The paper notes the hierarchy of differentiated transformational leadership and divides it into team-focus transformational leadership and individual-focus transformational leadership. It also provides a new mechanism and boundary condition, i.e. differentiated transformational leadership has an impact on employees' taking charge through psychological availability and collectivism orientation is a moderator.

This study aims to explore how tourists construct destination images in the context of dark tourism and reveals the relationships between on-site experience, destination image and behavioural intention.

The earthquake-ravaged county town of Beichuan in China was chosen as the study site. The study collected 298 viable questionnaires from tourists. Partial least squares structural equation modelling was performed to explore the relationships between the variables of on-site experience, destination image and behavioural intention.

The study identified four dimensions of dark tourism destination image (TDI) from its attribute and functional perspective. It found that “image of memorial place” and “image of educational place” were the most perceptual images and positively related with most subdimensions of on-site experience and behavioural intention. “Image of leisure place” and “image of landscapes of fear” were less perceived by tourists and negatively related with some subdimensions of on-site experience and behavioural intention.

To our knowledge, this study is the first attempt to explore the complex mechanisms of dark TDI formation with the framework of “on-site experiences–destination images–behavioural intentions”. By identifying tourists’ most and least perceptual images and their effective antecedents and consequences help to reconcile and manage the controversial and contradictory images of a dark tourism destination.

本文探讨了游客如何建构黑色旅游目的地形象, 进一步研究了游客现场体验、目的地形象、行为意愿之间的作用关系。

以汶川地震重灾区北川老县城遗址为案例地, 本研究收集了游客结构化问卷298份, 采用偏最小二乘结构方程模型（PLS-SEM）分析了游客现场体验、目的地形象和行为意愿各维度之间的作用关系。

从目的地属性和功能角度, 本文区分了黑色旅游目的地形象四个维度。研究发现“纪念地形象”和“教育地形象”是游客感知最强的两大维度, 与绝大多数游客现场体验和行为意愿的维度呈显著正向影响关系。 “休闲地形象”和“恐惧景观形象”, 游客感知较弱, 与现场体验和行为意向的一些维度呈负向影响关系。

本文首次利用“现场体验-目的地形象-行为意愿”这一研究框架, 揭示黑色旅游目的地形象的复杂生成机制。通过识别游客感知最强和最弱的形象维度, 揭示其前因与后果, 有助于调和与管理有争议和矛盾的黑色旅游目的地形象。

Este estudio explora cómo los turistas construyen la imagen del destino en el contexto del turismo oscuro, revelando las relaciones entre experiencias en el lugar, imágenes del destino e intenciones de comportamiento.

El terremoto que devastó la ciudad del condado de Beichuan en China fue elegido lugar de estudio por sus peculiaridades para el desarrollo del destino oscuro. El estudio recopiló 298 cuestionarios viables de turistas. Se planteo un modelo de ecuaciones estructurales (PLS-SEM) para explorar las relaciones entre las variables de experiencias en el lugar, imágenes de destino e intenciones de comportamiento.

El estudio identificó cuatro dimensiones de la imagen del destino turístico oscuro desde su atributo y perspectiva funcional. De igual forma, se encontró que la “imagen del lugar conmemorativo” y la “imagen del lugar educativo” eran las imágenes más perceptivas y estaban relacionadas positivamente con la mayoría de los subdimensiones de las experiencias en el lugar e intenciones de comportamiento. Los turistas percibieron menos la “imagen de un lugar de ocio” y la “imagen de paisajes de miedo” y se relacionaron negativamente con algunos subdimensiones de las experiencias en el lugar e intención de comportamiento.

Hasta donde sabemos, este estudio es el primer intento de explorar el complejo mecanismo en la formación de TDIs oscuros con el marco de “experiencias en el lugar- imágenes de destino – intenciones de comportamiento”. Al identificar las imágenes más o menos perceptivas de los turistas, y sus antecedentes y consecuencias efectivos, ayuda a conciliar y gestionar las imágenes controvertidas y contradictorias de un destino turístico oscuro.

The increase of turbulence sources and risk points under the complex social information network has brought severe challenges. This paper discusses risk perception and intelligent decision-making under the complex social information network to maintain social security and financial security.

Cross-modal semantic fusion and social risk perception, temporal knowledge graph and analysis, complex social network intelligent decision-making methods have been studied. A big data computing platform of software and hardware integration for security combat is constructed based on the technical support.

The software and hardware integration platform driven by big data can realize joint identification of significant risks, intelligent analysis and large-scale group decision-making.

The integrated platform can monitor the abnormal operation and potential associated risks of Listed Companies in real-time, reduce information asymmetry and accounting costs and improve the capital market's ability to serve the real economy. It can also provide critical technical support and decision support in necessary public opinion monitoring and control business.

In this paper, the theory of knowledge-enhanced multi-modal multi-granularity dynamic risk analysis and intelligent group decision-making and the idea of an inference think tank (I-aid-S) is proposed. New technologies and methods, such as association analysis, time series evolution and super large-scale group decision-making, have been established. It's also applied in behavior and situation deduction, public opinion and finance and provides real-time, dynamic, fast and high-quality think tank services.

Using a Southeast Asian context, this paper asks a question that has seldom been researched: Is there a divergence between parents’ and their college-going children’s perceptions of education and employability at a time of rapid economic change? If such a divergence exists, it would have hidden costs for the children. Parents’ choice of professions no longer in demand when their children reach working age can permanently damage the latter’s earning power. Also, parents’ choice of fields of study that their children are not proficient or interested in jeopardizes the latter’s chances of success in their studies. The paper aims to discuss these issues.

Data were collected using mixed methods, a combination of structured online questionnaires from two local special-purpose sample surveys conducted by the authors, and follow-up interviews. Graduate Employment Survey 2 (GES2) was the second of a three-phase British Council-sponsored study, focusing on TNE, that used a structured online questionnaire for students of several tertiary education institutions, both in the public and private sectors, and for several group interviews of students in 2015. A structured questionnaire was also administered to a small number of parents.

In terms of employment, the rankings of HEIs by parents and students were generally consistent. Study in foreign HEIs abroad has the highest likelihood of employment. Branch campuses were ranked next highest. Despite this, of interest is the difference in mean scores between first and second ranked HEIs. Whereas students rate branch campuses as not much inferior to foreign university campuses, parents see a major gulf between them – they rate foreign campuses more highly than branch campuses more poorly. This difference is likely caused by parents’ traditional preference for foreign study over local, coupled with a lack of TNE knowledge.

A fundamental issue of perception is how parents and students see the role of education. Is education a destination or is education a journey? This disconnect has consequences. Given the shifting nature of employment, the need for transferable skills and the fact that some of the jobs that the next generation will be doing are not even known today, parental advice based on what they know may not do justice to their children’s choice of career. Likewise, the approach of TNE to promote traditional degrees to job paths is also a conventional approach that has a limited shelf life.

The role of parents in education choice has received surprisingly scant academic attention. With technological change driving product and service innovation ever more rapidly, previously unknown types of work have emerged in a relatively short span of time. In this situation, the risk of mismatched perceptions between parents and their children, whose educational experience spans a generation, is becoming increasingly real. While most studies of a parental role have been undertaken for Western countries, there is much less research on East Asian parents’ role in their children’s education.