Jian Wang, Jing Feng Shen and Ya Wen Fan
The spherical hybrid sliding bearings (SHSBs) can be used in ultra-precision and heavy-duty machine tools. However, there is little related research for these bearings. The…
Abstract
Purpose
The spherical hybrid sliding bearings (SHSBs) can be used in ultra-precision and heavy-duty machine tools. However, there is little related research for these bearings. The purpose of this study is to investigate the static characteristics and effect factors affecting SHSBs by fluid lubrication.
Design/methodology/approach
Based on the theories of fluid lubrication, the Reynolds equation of general Newtonian fluid is derived to obtain the steady-state lubrication equation. The system is solved by the finite difference method and the relaxation iterative method on the staggered grid to obtain the thickness and the pressure distribution of the oil film. The radial and axial load capacities of SHSBs are determined by the pressure field integration over the spherical surface.
Findings
The results show that the parameters such as oil supply pressure, bearing clearance, eccentricity ratio, rotating speed and orifices’ number affecting the static characteristics of bearings are significant and the cross-coupling effect exists.
Originality/value
The lubrication model of SHSB is established to analyze the pressure distribution with a variety of oil film thickness. The laws of oil supply pressure, bearing clearance, eccentricity ratio, rotating speed and orifices’ number on the load capacities are researched.
Details
Keywords
Pınar Özbilen, Alev Özer Torgalöz and Sevgin Batuk Ünlü
This chapter aims to investigate sentiments of blue-collar workers, specifically couriers, during Covid-19 pandemic. Data are collected from the online review posting platform…
Abstract
This chapter aims to investigate sentiments of blue-collar workers, specifically couriers, during Covid-19 pandemic. Data are collected from the online review posting platform, where employees and previous employees of a Turkish delivery company posted their comments on the company as an employer. The results reveal that there are mainly four topics on which the reviewers discuss: work environment, compensation, salary and working hours, and lay-off procedures. The analyses indicate that the most discussed topic is compensation, while the most negative sentiments appear to be on lay-off procedures.
Details
Keywords
Samridhi Garg, Monica Puri Sikka and Vinay Kumar Midha
Perspiration and heat are produced by the body and must be eliminated to maintain a stable body temperature. Sweat, heat and air must pass through the fabric to be comfortable…
Abstract
Purpose
Perspiration and heat are produced by the body and must be eliminated to maintain a stable body temperature. Sweat, heat and air must pass through the fabric to be comfortable. The cloth absorbs sweat and then releases it, allowing the body to chill down. By capillary action, moisture is driven away from fabric pores or sucked out of yarns. Convectional air movement improves sweat drainage, which may aid in body temperature reduction. Clothing reduces the skin's ability to transport heat and moisture to the outside. Excessive moisture makes clothing stick to the skin, whereas excessive heat induces heat stress, making the user uncomfortable. Wet heat loss is significantly more difficult to understand than dry heat loss. The purpose of this study is to provided a good compilation of complete information on wet thermal comfort of textile and technological elements to be consider while constructing protective apparel.
Design/methodology/approach
This paper aims to critically review studies on the thermal comfort of textiles in wet conditions and assess the results to guide future research.
Findings
Several recent studies focused on wet textiles' impact on comfort. Moisture reduces the fabric's thermal insulation value while also altering its moisture characteristics. Moisture and heat conductivity were linked. Sweat and other factors impact fabric comfort. So, while evaluating a fabric's comfort, consider both external and inside moisture.
Originality/value
The systematic literature review in this research focuses on wet thermal comfort and technological elements to consider while constructing protective apparel.
Details
Keywords
Fan Wen, Zhenshen Qu and Changhong Wang
The purpose of this paper is to describe how, in order to fulfill the specific missions under some special environments without people participating, a multi‐robot object tracking…
Abstract
Purpose
The purpose of this paper is to describe how, in order to fulfill the specific missions under some special environments without people participating, a multi‐robot object tracking and docking systems are designed based on networked control frames.
Design/methodology/approach
In the process of target recognition and tracking, the tracking robot obtains the target robot's position and poses information by means of multi‐sensors, and tracking the target robot uses a data fusion algorithm based on network‐delay. In the phase of docking, the exterior parameters of the CCD camera installed on the tracking robot can be calculated in‐phase by recognizing the coded target in a place on the target robot. Finally, the relative position and pose parameters between the tracking robot and the target robot can be derived using the coordinate rotation parameters.
Findings
The experiment results indicated that the relative position measure error is less than 1.5 percent, and the relative pose measure error less than 1° within 1.5‐10 m. The research results show that the system can actualize object tracing and docking missions accurately and timely.
Research limitations/implications
This paper is devoted to multi‐robot object tracking and docking systems.
Practical implications
The main applications are in the exploration in the seabed, consignment in the workshop, formation of spacecrafts, docking of spacecrafts, and so on.
Originality/value
The system can actualize object tracing and docking missions accurately, and the system is of reliable, real‐time, and robust capabilities. This will aid all developers and researchers to enhance their technicality.
Details
Keywords
Kuo‐Fang Peng, Yi‐Wen Fan and Tong‐An Hsu
This study chooses the content perception perspective to develop a theoretical model portraying the psychological activities of Web surfers exposed to content Web sites. After…
Abstract
This study chooses the content perception perspective to develop a theoretical model portraying the psychological activities of Web surfers exposed to content Web sites. After collecting 549 empirical observations in a controlled lab environment, tests the theoretical relationships by using the structural equation modelling (SEM) technique. The results strongly indicate that effective content perceptual dimensions can help content Web surfers to develop positive attitudes toward content sites, which in turn induce favorable behavioral outcomes such as frequent site usage and loyalty. Such a proposed theoretical model not only has the potential to enrich the theoretical underpinning of Internet studies but also presents a practical framework to guide content strategy formulations for the online content industry. Detailed implications for both managerial research and practice are discussed.
Details
Keywords
Charles Tilly argues that continuous wars and preparation for wars motivated early European rulers to extract resources from their subject populations, thereby expanding states’…
Abstract
Charles Tilly argues that continuous wars and preparation for wars motivated early European rulers to extract resources from their subject populations, thereby expanding states’ infrastructure and establishing mechanisms to enable negotiations with societies. State capacity was thus strengthened. Tilly's argument has inspired a wave of scholarship to reconsider state building in various regions of the Third World. Analysts of the Third World employ two theoretical elements inferred from Tilly to account for the failures of many Third World states. One is that without continuous international wars (as early modern Europe had), there would be no capable and effective states. The other element is that availability of foreign aid from the global powers so unique to the Cold War Era exempted Third World states from extracting resources from their societies. I call these analyses Tillian theories of the Third World.
Tillian analysts acknowledge that the capable state in Taiwan during the Cold War stood out from its Third World counterparts. However, the Tillian generalization of the Third World does not account for Taiwan's state-building path. Taiwan's experience is situated in a perplexity between the two variables above: On the one hand, Taiwan resembles early modern European state formation with high military expenditures and a huge standing army prepared for war. In the Tillian model, this condition enhances state capacity. On the other hand, Taiwan was a huge US aid recipient in the Cold War, second only to South Korea. In the Tillian model, this degrades the state's effectiveness, contrary to Taiwan's experience. Solving this puzzle will revise Tillian logics of state building. That, however, is beyond the scope of this paper. Instead, through literature review and presentation of empirical evidences, I suggest some analytical directions for future research to enhance our understanding of Taiwan's state-building trajectory in particular and of Third World states in general.
Chao‐Min Chiu, Eric T.G. Wang, Fu‐Jong Shih and Yi‐Wen Fan
The purpose of this paper is to investigate the motivations behind people's intentions to continue knowledge sharing (continuance intention) in open professional virtual…
Abstract
Purpose
The purpose of this paper is to investigate the motivations behind people's intentions to continue knowledge sharing (continuance intention) in open professional virtual communities.
Design/methodology/approach
Data collected from 270 members of a professional virtual community provides partial support for the proposed model. LISREL 8.5 was used to analyse the measurement and structural models.
Findings
The results show that playfulness is critical for the community members' satisfaction and continuance intention. However, only positive self‐worth disconfirmation, distributive justice, and interactional justice can influence the satisfaction of the community members.
Research limitations/implications
The data were collected from a single open professional community; the generalisation of the model and findings to other virtual communities requires additional research. The findings imply that justice factors appear to be important in leading to higher satisfaction levels.
Practical implications
Developers of virtual communities should create a more enjoyable online environment and raise the core knowledge contributors' sense of self‐worth.
Originality/value
A theoretical model was constructed in which individual motivation factors, social network factors, and justice theory are integrated with expectancy disconfirmation theory to investigate the motivations behind people's continuance intention.
Details
Keywords
Mobile devices, through their capacity to enable anytime-anywhere learning as well as capture, annotate and share multimedia, offer entirely new ways for students to learn. This…
Abstract
Mobile devices, through their capacity to enable anytime-anywhere learning as well as capture, annotate and share multimedia, offer entirely new ways for students to learn. This chapter provides review of mobile learning with a particular focus on learning design. First various definitions and characteristics of mobile learning are examined in order to establish a common understanding of its boundaries and meaning. Example uses of mobile learning in schools and higher education are described as a way to provide a more concrete understanding of design possibilities. Benefits of mobile learning are unpacked, as distilled from the literature, including the ability to provide flexible, accessible, authentic, personalized, ubiquitous and seamless learning. Mobile learning issues are also examined, including technical problems, cognitive load issues, distraction, equity and safety. A primary school science and a university pre-service teacher education vignette are described so as to offer a more in-depth illustration of what mobile learning can look like and achieve in practice. Finally, mobile learning research findings and observations are synthesized into recommendations, to inform and guide evidence-based mobile learning design practices. Opportunities for future research and investigation are also discussed.
Chien Hsiang Liao, Jung-Kuei Hsieh and Sushant Kumar
On Instagram, a verified badge (a blue checkmark) is used to confirm the authenticity of influencers' accounts for consumers. Yet, it is unclear whether followers trust the badge…
Abstract
Purpose
On Instagram, a verified badge (a blue checkmark) is used to confirm the authenticity of influencers' accounts for consumers. Yet, it is unclear whether followers trust the badge or are influenced by the influencer's large following. This research aims to investigate the impact of verified badges on followers' trust and behavioral intentions.
Design/methodology/approach
This research conducts three experiments to investigate the impact of the verified badge on consumer attitudes and behavioral intentions, recruiting participants from freelance recruiting website in all three experiments.
Findings
The results show that a verified badge can sequentially influence consumer trust, attitude and sharing intentions. Furthermore, the impact of the verified badge on trust is more pronounced among micro-influencers as opposed to macro-influencers, and it can mitigate the negative attitude toward commercial postings.
Originality/value
Based on trust transfer theory, this research is a pioneer in investigating the effectiveness of verified badges on social media. These findings contribute to the field of influencer marketing by considering influencers' characteristics and the commercial intent of postings as moderators. Additionally, the results offer managerial insights for developing influencer marketing strategies.
Details
Keywords
I first met Charles C. Moskos back in 1983, at the first international conference in which I had the fortune to participate, and, since my history of relations with him parallels…
Abstract
I first met Charles C. Moskos back in 1983, at the first international conference in which I had the fortune to participate, and, since my history of relations with him parallels those of many colleagues and friends who study the military and who, like me, remember him, it seems worthwhile to introduce these studies in his honour with a personal recollection.