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A new backward punch shape was designed and used in the hydroforming process of double-layer Y-shaped tubes to achieve uniform wall thickness. This study focuses on the implementation and effectiveness of this novel punch shape.

A numerical simulation and experimental validation of the hydroforming process of double-layer Y-shaped tubes under various backward punch, replenishment ratios (left and right feed ratios) and internal pressure loading paths was performed using finite elements. During the hydroforming process, an analysis was made on the distribution of stress, strain and wall thickness in both the inner and outer layers of the Y-shaped conduit.

The novel backward punch parallel to the main tube has been found to improve the distribution of wall thickness in Y-shaped tubes. By controlling the feeding ratio and modifying the loading path of the internal pressure, it is possible to obtain the optimal forming part of the double-layer Y-shaped tube. The comparison between the simulation and experimental results of the double-layer Y-shaped tube formed under the optimal path indicates that the error is within 5% and the distribution of wall thickness is consistent.

A novel backward punch technique is employed to control the hydroforming process in a Y-shaped tube. A study on hydroforming of double-layer Y-shaped tubes with asymmetric features and challenging forming conditions is being suggested.

Blade tip clearance has always been a concern for the gas turbine design and control. The numerical analysis of tip clearance is based on the turbine components displacement. The purpose of this paper is to investigate the thermal and mechanical effects on a real cooling blade rather than the simplified model.

The coupled fluid-solid method is used. The thermal analysis involves solid and fluid domains. The distributions of blade temperature, stress and displacement have been calculated numerically under real turbine operating conditions.

Temperature contour can provide a reference for stress analysis. The results show that temperature gradient is the main source of solid stress and radial displacement. Compared with thermal or mechanical effect, there is a great change of stress magnitude for the thermomechanical effect. Large stress gradients are found between the leading and trailing edge of turbine cooling blade. Also, the blade radial displacement is mainly attributed to the thermal load rather than the centrifugal force. The analysis of the practical three-dimensional model has achieved the more precise results.

It is significant for clearance design and life prediction.

This paper aims to investigate the fretting wear mechanism of an Al-Li alloy at room temperature, the tangential fretting wear tests were carried out.

The effects of displacement amplitude and fretting frequency on the tangential fretting wear characteristics were mainly investigated. The experimental data obtained are analyzed and compared.

The results indicated that the fretting friction coefficient increased with the increase of displacement amplitude. As the displacement amplitude increased, the wear scar morphology changed significantly, mainly in terms of delamination debris and furrow scratches. The wear mechanism changed from initial mild wear to more severe oxidative wear, adhesive wear and abrasive wear.

This paper extends the knowledge into mechanical tight connections. The conclusions can provide theoretical guidance for the fretting of mechanical tight connections in the field of automotive lightweight and aerospace.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2019-0490/

Established in 1967 by the National Service (Amendment) Bill, National Service (NS) makes it compulsory for most young Singaporean males to enlist in the armed forces, typically for a two-year period. NS comes at a critical juncture in most Singaporean mens’ adolescence, disrupting their lives and isolating them in a foreign environment just as they are beginning to form a firm sense of identity. Recruits are expected to go through grueling training and endure harsh scoldings to prove their worth as both soldiers and men. Through an interview with 14 individuals who have served or are serving NS, it is found that the hegemonic masculinity present in NS relies on norms of strength, leadership, and suppression of emotion. However, its impact on enlistees is inconsistent, and dependent on one’s vocation, personal encounters, and expectations prior to enlisting.

The information used for supervision by regulatory departments in public-private partnership (PPP) projects is primarily transmitted and processed by the PPP implementation department, which negatively impacts the information quality, leading to information asymmetry and undermining the overall effectiveness of supervision. This study aims to explore how to use blockchain to anchor the information used for supervision in PPP projects to the original information, to strengthen the oversight.

This paper adopts the principles of design science research (DSR) to design a conceptual framework that systematically organizes information along the information dissemination chain, ensuring the reliable anchoring of original information. Two-stage interviews involving experts from academia and industry are conducted, serving as formative and summative evaluations to guide the design.

The framework establishes a weak-centralized information organizing mode, including the design of governance community and on-chain and off-chain governance mechanisms. Feedback from experts is collected via interviews and the designed framework is thought to improve information used for supervision. Constructive suggestions are also collected and analyzed for further development.

This paper provides a novel example exploring the inspirations blockchain can bring to project governance, like exercising caution regarding the disorderly expansion of public sector authority in addressing information disadvantages and how to leverage blockchain to achieve this. Technical details conveyed by the framework deepen understanding of how blockchain benefits and the challenges faced in successful implementation for practitioners and policymakers. The targeted evaluation serves as rigorous validation, guiding experts to provide reliable feedback and richer insights by offering them a more cognitively convenient scenario.

Against the background of industrialisation and modernisation of agriculture, food production issues and environmental hazards have become more and more obvious and consumers are increasingly concerned about food safety and health, which is strengthening demand for organic food. E-commerce provides a new channel for sales. Research on consumer trust in online organic food sales is the basis of network marketing. The paper aims to discuss these issues.

A laboratory experiment was used to empirically test the effects of media richness on consumers’ trust and the moderating effect of online review length. A 2×2 factorial design (i.e. two types of online product presentation formats (between-subject)×two levels of online review lengths (between-subject)) was used.

Media richness has a significant positive effect on consumers’ trust and that this effect is moderated by online review length. Meanwhile, perceived risk conveys the interaction effect of the media richness of online product presentation and online review length to trust.

E-commerce websites should aim to promote organic food by using a variety of online product presentation formats and by presenting high quality online reviews in order to reduce consumers’ perceived risk and improve their degree of trust when buying online.

This paper provides a new insight into consumers’ attitude of buying organic food online. The results of the research could provide proposals for promoting organic food sales online.

The purpose of this paper is twofold: first, to explore how the number of structural holes influences the possibility of risk propagation in R&D networks; and second, to investigate how the specific context of tie strength and common cognition moderate the association between structural holes and risk propagation.

This study focuses on how structural holes influence risk propagation under the specific context of relationship and cognitive dimension by drawing on social capital theory. Risk sharing and risk perception as mediating variables are employed in the proposed conceptual model. The authors issued questionnaires to managers and R&D personnel participating in R&D projects and collaboration in Shanghai and Jiangsu province through e-mail and face to face. The data were used to carry out multiple regression analysis to test hypotheses.

The results show that relationship between structural holes and risk propagation of R&D network is U-shaped. Risk perception and risk sharing partially mediate the relationship between structural holes and risk propagation. Tie strength significantly moderates the relationship between structural holes and risk sharing, but insignificantly moderates the association between structural holes and risk perception. Common cognition significantly moderates the associations between structural holes and risk sharing, and structural holes and risk perception, respectively.

This study provides a distinctive theoretical perspective for social capital and risk management. It also offers managers a clear understanding of how to reduce or to avoid risk propagation by jointly leveraging the number of structural holes, tie strength and common cognition.

This paper aims to determine the key trust antecedents that influence Internet users’ trust level toward Internet service providers (ISPs) in a high-risk society. It also investigates trust-building process, major causes of its violation, their potential implications and restoration.

A mixed-method approach was used in collecting data in Kenya in 2014 by using questionnaire and interview techniques. The former was administered to 250 (with 81 per cent response rate) randomly selected Internet users at Kenyatta University while the latter focused on key decision-makers from four randomly selected ISPs in Nairobi.

The results show that Internet users’ perceptions of ISPs’ ability to be trusted in Kenya depend more on their competence in terms of service delivery (ability) and desire to protect users (benevolence) than upholding acceptable standards (integrity). The results also indicate a lack of trust manifested in poor communication and greed for profit among ISPs as major causes of trust violation.

This paper proposes two frameworks that can enhance Internet use by providing a better understanding of trust in a high-risk society.

This paper aims to collect and compile the historical data of Guanfu Salt Farm, officially built by the Song Dynasty (960–1279) within modern Hong Kong territories, to reconstruct its history for the reflection of Hong Kong society of the time.

This paper is largely based on identification and analysis of historical documents, including keyword search on electronic databases and verification with the original sources, with reference to archaeological findings when necessary.

This paper reconstructs the history of Guanfu Salt Farm based on documentary sources with reference to archaeological findings. English translation of Chinese sources is also provided when necessary.

There has been an absence of systematic compilation of historical data of Hong Kong during the Song Dynasty, which are limited in quantity and scattered across different sources. This paper seeks to fill the vacuum of knowledge about pre-colonial Hong Kong, with a more comprehensive reconstruction of the history of Guanfu Salt Farm.

The purpose of this paper is to examine consumer attitudes toward genetically modified (GM) and organic foods with a broader list of control variables that includes green attitudes, impulsive purchasing, concerns about privacy, religiosity, birth order, and political preferences.

US internet panelists were asked about their preferences for purchasing non-GM produce, non-GM cereal, and organic products even if they cost a little more. They were also asked if genetically engineered foods are safe to consume. Responses to these four questions were dependent variables in binary logistic regressions. The sample size was 725 adults.

Attitudes toward non-GM produce and non-GM cereal were linked with different variables. Green attitudes were positively linked with non-GM and organic food attitudes. Impulsive purchases, a religiosity factor, and a privacy concern factor were linked with non-GM but not organic food attitudes. Social desirability bias was also significant. The genetically engineered food model identified some unique linkages with the control variables, suggesting that these terms may not improve consumer confidence with food.

New measures and several variables that researchers independently found to be significant were tested together in models and found to be linked with organic and non-GM food attitudes. Some expected relationships were not found. The results provide better profiles of consumers who have strong attitudes toward GM and organic foods.