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1 – 10 of 11Changpeng Chen, Jie Yin, Haihong Zhu, Xiaoyan Zeng, Guoqing Wang, Linda Ke, Junjie Zhu and Shijie Chang
High residual stress caused by the high temperature gradient brings undesired effects such as shrinkage and cracking in selective laser melting (SLM). The purpose of this study is…
Abstract
Purpose
High residual stress caused by the high temperature gradient brings undesired effects such as shrinkage and cracking in selective laser melting (SLM). The purpose of this study is to predict the residual stress distribution and the effect of process parameters on the residual stress of selective laser melted (SLMed) Inconel 718 thin-walled part.
Design/methodology/approach
A three-dimensional (3D) indirect sequentially coupled thermal–mechanical finite element model was developed to predict the residual stress distribution of SLMed Inconel 718 thin-walled part. The material properties dependent on temperature were taken into account in both thermal and mechanical analyses, and the thermal elastic–plastic behavior of the material was also considered.
Findings
The residual stress changes from compressive stress to tensile stress along the deposition direction, and the residual stress increases with the deposition height. The maximum stress occurs at both ends of the interface between the part and substrate, while the second largest stress occurs near the top center of the part. The residual stress increases with the laser power, with the maximum equivalent stress increasing by 21.79 per cent as the laser power increases from 250 to 450 W. The residual stress decreases with an increase in scan speed with a reduction in the maximum equivalent stress of 13.67 per cent, as the scan speed increases from 500 to 1,000 mm/s. The residual stress decreases with an increase in layer thickness, and the maximum equivalent stress reduces by 33.12 per cent as the layer thickness increases from 20 to 60µm.
Originality/value
The residual stress distribution and effect of process parameters on the residual stress of SLMed Inconel 718 thin-walled part are investigated in detail. This study provides a better understanding of the residual stress in SLM and constructive guidance for process parameters optimization.
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Yong Cheng, Zhongxu Xiao, Haihong Zhu, Xiaoyan Zeng and Guoqing Wang
Selective laser melting (SLM) is a promising additive manufacturing technology in the field of complex parts’ fabrication. High temperature gradient and residual stress are vital…
Abstract
Purpose
Selective laser melting (SLM) is a promising additive manufacturing technology in the field of complex parts’ fabrication. High temperature gradient and residual stress are vital problems for the development of SLM technology. The purpose of this paper is to investigate the influence of substrate characteristics on the residual stress of SLMed Inconel 718 (IN718).
Design/methodology/approach
The SLMed IN718 samples were fabricated on the substrates with different characteristics, including pre-compression stress, materials and pre-heating. The residual stress at the center of the top surface was measured and compared through Vickers micro-indentation.
Findings
The results indicate that the residual stress reduces when the substrate contains pre-compression stress before the SLM process starts. Both substrate thermal expansion coefficient and thermal conductivity affect the residual stress. In addition to reducing the difference of thermal expansion coefficient between the substrate and the deposited material, the substrate with low thermal conductivity can also decrease the residual stress. Substrate pre-heating at 150°C reduces nearly 42.6 per cent residual stress because of the reduction of the temperature gradient.
Originality/value
The influence of substrate characteristics on the residual stress has been studied. The investigation results can help to control the residual stress generated in SLM processing.
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The purpose of this paper is to bridge the knowledge gap in designing MBA strategy between China and the West by examining the content, context and process of MBA delivery. This…
Abstract
Purpose
The purpose of this paper is to bridge the knowledge gap in designing MBA strategy between China and the West by examining the content, context and process of MBA delivery. This paper challenges the assumptions and pedagogical approach underpinning the current design and delivery of MBA programmes that were originally moulded with Western management history and development in the era of globalization. There is consensus that MBA was used to train business managers; however, nowadays, people are inclined to state that MBA is used to develop global business leaders or full-fledged global competitors. How can we develop global business leaders without a global vision when designing MBA strategy?
Design/methodology/approach
Based on extensive literature review and critical analyses through the strategic management approach, this paper examines the status quo of current MBA programmes in the West and in China. This paper presents a conceptual framework that draws on the current MBA literature and on-going debates around management education and development in the West and in China.
Findings
The designing strategy of MBA has been originally strongly influenced by Western ideology and ethos. Therefore, the difficulties of management knowledge transfer are often explained through culture acclimatization and emphasize has been on cultural divergence rather than convergence. With synthesis between Western and Eastern management identified, we argue that the appropriateness and effectiveness of the traditional philosophy of MBA designing strategy based on Western management history has been challenged in the 21st century. The perception has fuelled criticism of business schools in the post-recession. They have come under fire for allegedly failing in their obligations to educate socially responsible business leaders (Barker, 2010). This leads to rethinking of the philosophy and vision underpinning the MBA designing strategy. A new philosophical approach – integration of Western management with Eastern philosophy has been under scrutiny, which is necessary in business education to enable future business leaders to become full-fledged competitors in the global market.
Originality/value
The output of this discussion helps to establish a conceptual framework which will provide strategic insight in enabling business/management school and MBA providers to address the current deficiency in MBA teaching and learning strategy and develop more appropriate arrangement when considering the design and development of a successful MBA programme in the 21st century.
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To examine the nature of Chinese business negotiating style in Sino‐Western business negotiations in business‐to‐business markets involving large industrial projects from a social…
Abstract
Purpose
To examine the nature of Chinese business negotiating style in Sino‐Western business negotiations in business‐to‐business markets involving large industrial projects from a social cultural point of view.
Design/methodology/approach
A conceptual approach developed from personal interviews.
Findings
This study reveals that the Chinese negotiator does not possess an absolute negotiating style but rather embraces a mixture of different roles together: “Maoist bureaucrat in learning”, “Confucian gentleman”, and “Sun Tzu‐like strategist”. The Chinese negotiating strategy is essentially a combination of cooperation and competition (termed as the “coop‐comp” negotiation strategy in this study). Trust is the ultimate indicator of Chinese negotiating propensities and role choices.
Research limitations/implications
The focus of this study is on Chinese negotiating style shown in large B2B negotiations with Chinese SOEs.
Originality/value
Differing from most other studies on Chinese negotiating style which tend to depict the Chinese negotiator as either sincere or deceptive, this study points out that there exists an intrinsic paradox in Chinese negotiating style which reflects the Yin Yang thinking. The Chinese negotiator has a cultural capacity to negotiate both sincerely and deceptively and he/she changes coping strategies according to situation and context, all depending on the level of trust between negotiating partners.
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Shufeng Tang, Yongsheng Kou, Guoqing Zhao, Huijie Zhang, Hong Chang, Xuewei Zhang and Yunhe Zou
The purpose of this paper is to design a climbing robot connected by a connecting rod mechanism to achieve multi-functional tasks such as obstacles crossing and climbing of power…
Abstract
Purpose
The purpose of this paper is to design a climbing robot connected by a connecting rod mechanism to achieve multi-functional tasks such as obstacles crossing and climbing of power transmission towers.
Design/methodology/approach
A connecting rod type gripper has been designed to achieve stable grasping of angle steel. Before grasping, use coordination between structures to achieve stable docking and grasping. By using the alternating movements of two claws and the middle climbing mechanism, the climbing and obstacle crossing of the angle steel were achieved.
Findings
Through a simple linkage mechanism, a climbing robot has been designed, greatly reducing the overall mass of the robot. It can also carry a load of 1 kg, and the climbing mechanism can perform stable climbing. The maximum step distance of the climbing robot is 543 mm, which can achieve the crossing of angle steel obstacles.
Originality/value
A transmission tower climbing mechanism was proposed by analyzing the working environment. Through the locking ability of the screw nut, stable clamping of the angle steel is achieved, and a pitch mechanism is designed to adjust the posture of the hand claw.
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Li Gao, Jinnan Song, Jiajuan Liang and Jianxiao Guo
This paper aims to explore the influence of founder shareholders’ resources on the allocation of control rights from the perspective of incomplete contract theory and…
Abstract
Purpose
This paper aims to explore the influence of founder shareholders’ resources on the allocation of control rights from the perspective of incomplete contract theory and resource-based theory.
Design/methodology/approach
This paper analyzes newspaper materials with NVivo11on a case of battle for corporate control in Chinese top-listed company-Vanke Group.
Findings
The research shows that human capital is the key resource and the holding proportion of financial resources directly affects the allocation of control rights. At the same time, social capital is unstable and easily broken. At last, institutional environment also affects the degree between the relationship of founder shareholders’ resources and the allocation of control rights. The influence of founder-shareholder resources on the allocation of control rights follows the path of “crisis – founder-shareholder’s resources – founder’s ability - allocation of control rights.”
Research limitations/implications
This study only selects the financial capital, human capital and social capital of Shi Wang, the founder of Vanke, as the analysis object. The study can expand the types of founder shareholder resources to verify and enrich the conclusions.
Originality/value
The current theoretical research in the literature focuses on the necessity of equity and shareholder’s resources versus the control rights. Some key factors and mechanism on the relationship have not been fully clarified. The results of this paper not only extend the combination research of social network and corporate governance, but also provide enterprise founders with references for making reasonable decisions during control battle.
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This paper aims to add to the understanding of dynamic capabilities (DC) as sources of competitive advantage of successful Asian-Pacific shipping companies by demonstrating that…
Abstract
Purpose
This paper aims to add to the understanding of dynamic capabilities (DC) as sources of competitive advantage of successful Asian-Pacific shipping companies by demonstrating that DC development unfolds in three steps, from recognition that the environment has changed, to the decision to deploy DC, to assets re-orchestration.
Design/methodology/approach
Based on an approach involving two illustrative case studies, the author analyzed DC development of Chinese and Singaporean-based shipping groups in depth. The analysis was centered on DC by investigating how strategic decision-making on vertical integration, diversification and implementation of new technologies can be underpinned by developing DC to create sustained advantages.
Findings
The author found that strategic components of DC are rooted in strategic decision-making to initiate changes on the corporate and even on an operational level.
Research limitations/implications
While capability development is thoroughly studied, capability erosion has not been integrated into the research. The exploration of human capital as a firm’s idiosyncratic resource in assets orchestration capabilities can be future work.
Practical implications
The proposed research contributes to the debate on micro foundations of DC and provides insights for practitioners striving for retaining competitive advantages.
Social implications
Regarding implications for the society, the research shows how the DC serve to generate competitive advantages. The author has presented a logical structure of the competitive advantage paradigm as a product of DC and business models that can be useful to decision makers.
Originality/value
The research offers insights into the composition of micro foundations of DC and demonstrates that DC can be unbounded into well-known and concrete strategic and operational management activities.
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Matthew Tickle, Sarah Schiffling and Gaurav Verma
This paper aims to explore the impact of fourth-party logistics (4PL) adoption on the agility, adaptability and alignment (AAA) capabilities within humanitarian supply chains…
Abstract
Purpose
This paper aims to explore the impact of fourth-party logistics (4PL) adoption on the agility, adaptability and alignment (AAA) capabilities within humanitarian supply chains (HSCs).
Design/methodology/approach
Semi-structured interviews with individuals from a large non-government organisation were combined with secondary data to assess the influence of 4PL adoption on AAA capabilities in HSCs.
Findings
The results indicate that HSCs exhibit some of the AAA antecedents but not all are fully realised. While 4PL positively affects the AAA capabilities of HSCs, its adoption faces challenges such as the funding environment, data security/confidentiality and alignment with humanitarian principles. The study suggests an AAA antecedent realignment, positioning alignment as a precursor to agility and adaptability. It also identifies three core antecedents in HSCs: flexibility, speed and environmental uncertainty.
Practical implications
The study shows the positive impact 4PL adoption can have on the AAA capabilities of HSCs. The findings have practical relevance for those wishing to optimise HSC performance through 4PL adoption, by identifying the inhibiting factors to its adoption as well as strategies to address them.
Originality/value
This research empirically explores 4PL’s impact on AAA capabilities in HSCs, highlighting the facilitating and hindering factors of 4PL adoption in this environment as well as endorsing a realignment of AAA antecedents. It also contributes to the growing research on SC operations in volatile settings.
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Marek Michalczuk, Bartlomiej Ufnalski and Lech M. Grzesiak
The purpose of this paper is to provide high-efficiency and high-power hybrid energy source for an urban electric vehicle. A power management strategy based on fuzzy logic has…
Abstract
Purpose
The purpose of this paper is to provide high-efficiency and high-power hybrid energy source for an urban electric vehicle. A power management strategy based on fuzzy logic has been introduced for battery-ultracapacitor (UC) energy storage.
Design/methodology/approach
The paper describes the design and construction of on-board hybrid source. The proposed energy storage system consists of battery, UCs and two DC/DC interleaved converters interfacing both storages. A fuzzy-logic controller (FLC) for the hybrid energy source is developed and discussed. Control structure has been tested using a non-mobile experimental setup.
Findings
The hybrid energy storage ensures high-power ability. Flexibility and robustness offered by the FLC give an easy accessible method to provide a power management algorithm extended with additional input information from road infrastructure or other vehicles. In the presented research, it was examined that using information related to the topography of the road in the control structure helps to improve hybrid storage performance.
Research limitations/implications
The proposed control algorithm is about to be validated also in an experimental car.
Originality/value
Exploratory studies have been provided to investigate the benefits of energy storage hybridization for electric vehicle. Simulation and experimental results confirm that the combination of lithium batteries and UCs improves performance and reliability of the energy source. To reduce power impulses drawn from the battery, power management algorithm takes into consideration information on slope of a terrain.
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The purpose of this paper is to investigate the influence of binder effect on tribological behavior of brake friction composite materials: a case study of phenolic resin modified…
Abstract
Purpose
The purpose of this paper is to investigate the influence of binder effect on tribological behavior of brake friction composite materials: a case study of phenolic resin modified by N-Methylaniline.
Design/methodology/approach
Four different friction materials have been fabricated by varying modified phenolic resin content. The samples were prepared by the conventional powder metallurgy methods following ball milling, mixing, pre-forming, hot pressing and post-curing processes. Thermogravimetric analysis was used to determination of the degradation mechanism of organic components and study of thermal stability of the samples. A friction test was carried out in dry conditions using a vertical tribometer. Analysis of worn surfaces was performed using a scanning electron microscope.
Findings
The experimental results revealed that the sample containing 25 Wt.% phenolic resin has good mechanical and thermal properties with stable friction characteristics.
Originality/value
This paper presents the effect of N-methylaniline modified phenolic resin on friction composites to improve tribological performance by its thermal properties.
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