Haiyan Sun, Bo Gao and Jicong Zhao
This study aims to investigate the several parameters in wafer-level packaging (WLP) to find the most critical factor impacting the thermal fatigue life, such as the height of…
Abstract
Purpose
This study aims to investigate the several parameters in wafer-level packaging (WLP) to find the most critical factor impacting the thermal fatigue life, such as the height of copper post, the height of solder bump, the thickness of chip. The FEA results indicate the height of solder bumps is the most important factor in the whole structure.
Design/methodology/approach
The copper post bumps with 65 µm pitch are proposed to investigate the thermal-mechanical performance of WLP. The thermal cycle simulation is used to evaluate the reliability of WLP by using finite element analysis (FEA). Taguchi method is adopted to obtain the sensitivity of parameters of three-dimension finite element model, for an optimized configuration.
Findings
It can be found that the optimal design has increased thermal fatigue life by 147% compared with the original one.
Originality/value
It is concluded that the finite element simulation results show outstanding thermal-mechanical performances of the proposed 65 µm pitch copper post bumps of WLP, including low plastic strain, high thermal fatigue life, which are desired for mobile device.
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Sifeng Liu, Keqin Sheng and Jeffrey Forrest
The purpose of this paper is to show which models, uncertain or certain, simple or complicated, are more suitable when they are faced with incomplete information and inaccurate…
Abstract
Purpose
The purpose of this paper is to show which models, uncertain or certain, simple or complicated, are more suitable when they are faced with incomplete information and inaccurate data.
Design/methodology/approach
The characteristics of fuzzy mathematics, grey system theory, rough set theory and the basic characteristics of incomplete information and inaccurate data in uncertain systems are analysed.
Findings
The similarities and differences among fuzzy mathematics, grey system theory, rough set theory and probability statistics are compared. The principle of simplicity of scientific theories, methods, and models are discussed.
Practical implications
It is suggested that the tendency to concentrate on a complicated model isn't always necessary when faced with the condition of incomplete information and inaccurate data.
Originality/value
The paper shows that a more satisfied result can be obtained with an uncertain model than with a meticulous model on a certain situation.
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Sifeng Liu, Jeffrey Forrest and Yingjie Yang
The purpose of this paper is to introduce the elementary concepts and fundamental principles of grey systems and the main components of grey systems theory. Also to discuss the…
Abstract
Purpose
The purpose of this paper is to introduce the elementary concepts and fundamental principles of grey systems and the main components of grey systems theory. Also to discuss the astonishing progress that grey systems theory has made in the world of learning and its wide‐ranging applications in the entire spectrum of science.
Design/methodology/approach
The characteristics of unascertained systems including incomplete information and inaccuracies in data are analysed and four uncertain theories: probability statistics, fuzzy mathematics, grey system and rough set theory are compared. The scientific principle of simplicity and how precise models suffer from inaccuracies are also shown.
Findings
The four uncertain theories, probability statistics, fuzzy mathematics, grey system and rough set theory are examined with different research objects, different basic sets, different methods and procedures, different data requirements, different emphasis, different objectives and different characteristics.
Practical implications
The scientific principle of simplicity and how precise models suffer from inaccuracies are shown. So, precise models are not necessarily an effective means to deal with complex matters, especially in the case that the available information is incomplete and the collected data inaccurate.
Originality/value
The elementary concepts and fundamental principles of grey systems and the main components of grey systems theory are introduced briefly. The reader is given a general picture of grey systems theory as a new method for studying problems where partial information is known, partial information is unknown; especially for uncertain systems with few data points and poor information.
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Ning Sun, Sai Liang, Hui Li and Haiyan Song
This study aims to examine the effect of several types of ex post idiosyncratic deals (i-deals) on work–life balance and work well-being, focusing on the mediating effect of…
Abstract
Purpose
This study aims to examine the effect of several types of ex post idiosyncratic deals (i-deals) on work–life balance and work well-being, focusing on the mediating effect of work–life balance on the relationship between ex post i-deals and work well-being as well as the moderating effect of gender on the relationship between ex post i-deals and work–life balance in the hospitality industry.
Design/methodology/approach
This study uses a questionnaire survey of 642 hotel managers from developed cities in China and analyze the data with structural equation modeling. This study also conducts on-site interviews among 20 hotel managers to support conclusions of the survey.
Findings
The results indicate that task i-deals as well as career and incentives i-deals significantly promote work–life balance, thereby indirectly improving work well-being. However, the impact of flexibility i-deals on work–life balance and work well-being is insignificant. The influence of career and incentives i-deals on work–life balance for males is slightly stronger than that for females.
Practical implications
This study has practical implications for hotel employers in terms of using various ex post i-deals to motivate and retain hotel managers by improving personal work–life balance and work well-being.
Originality/value
As one of early attempts to highlight the potential of i-deals to serve as solutions for work–life conflicts and unhappiness issues among hotel managers, this study provides novel insights into the mediating process between ex post i-deals and work well-being from the work–life balance perspective as well as distinct influences of various ex post i-deals on work–life balance for male and female managers.
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Ning Sun, Haiyan Song and Hui Li
This paper aims to investigate how different types of idiosyncratic deals (i-deals) in the hospitality industry enhance occupational well-being (OWB) through organization-based…
Abstract
Purpose
This paper aims to investigate how different types of idiosyncratic deals (i-deals) in the hospitality industry enhance occupational well-being (OWB) through organization-based self-esteem (OBSE).
Design/methodology/approach
In 2019, 679 questionnaires were distributed to middle- and high-level managerial staff who had worked in high-end hotels in China for at least 1 year, and 642 valid responses were collected. The survey data were analyzed using structural equation modeling. Follow-up interviews were conducted with 20 hotel managers to verify and lend additional support to the survey findings.
Findings
Both task i-deals and career and incentives i-deals positively affected OBSE and OWB, whereas flexibility i-deals negatively affected OBSE. OBSE positively affected OWB, thereby mediating the relationships between the three types of i-deals and OWB.
Originality/value
This study is groundbreaking in its exploration of how various i-deals contribute to OWB through OBSE among middle- and high-level managerial staff. The findings provide initial evidence of the links between i deals, OBSE and OWB and demonstrate how i-deals can address the practical problem of the shortage and loss of competent operational and administrative talent in the hospitality industry.
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Although half a decade have already passed following the devastation of super typhoon Haiyan in November 2013, limited studies on the status of the seaweed aquaculture industry…
Abstract
Purpose
Although half a decade have already passed following the devastation of super typhoon Haiyan in November 2013, limited studies on the status of the seaweed aquaculture industry have been reportedly published, specifically on the gendered differences of the key players in the production activities. The purpose of this empirical research is to present the different characteristics of producers; technology used in farming; gendered differences in labor; sources of propagules; and yield, productivity and income of seaweed farmers in five rural-poor coastal communities in Eastern Samar, the Philippines.
Design/methodology/approach
The data were gathered through a combination of fieldworks and desk research and were analyzed using a value chain and gender needs assessment analyses. A four-part, self-made guide questionnaire was used as an instrument. The data were presented and analyzed using thematic analysis.
Findings
The results demonstrate that the modified monoline method is the technology used by the seaweed farmers. Propagules are usually supplied for free by the BFAR or bought from neighboring villages. A monthly income of PhP 19,500.00 (US$393.00) can be generated from seaweed farming. Division of labors in most of the seaweed production processes is equally distributed between men and women with help from their boys-and-girls children. Increasing further the number of lines per seaweed grower to at least 25 will enable them to go beyond the poverty threshold, based on 2015 figures of the Philippine Statistics Authority (PSA).
Research limitations/implications
This study provides additional empirical data to substantiate and prove that women’s active involvement in seaweed production provides them an important opportunity to earn some income for themselves and their families and contribute to livelihood and enterprise development in their communities.
Practical implications
This study is helpful in constructing an Industry Development Plan to serve as the Seaweed Industry Road Map for progress, thereby, helping men and women seaweed growers especially in rural-poor coastal areas.
Social implications
Aside from being conducted in a post-disaster context, the data and recommendations presented in this paper contribute to the body of knowledge that government and non-government institutions, private individuals and groups and the academia could use in understanding the economic, commercial and community development contributions, gaps and constraints in producing seaweed in rural-poor coastal communities.
Originality/value
This paper serves as an in-depth empirical study reflective of the post-disaster, current gendered labor practices, culture, knowledge and attitude of the seaweed producers in the Philippines. More importantly, this study was conducted by a local researcher, thereby reflecting empirical findings and recommendations that are strategic, gender and culture-sensitive and timely and relevant.
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Haiyan Song, Levent Altinay, Ning Sun and Xuan Lorna Wang
This study aims to use the theory of third places to understand how different kinds of social interactions in small hospitality businesses, such as restaurants and cafes, can…
Abstract
Purpose
This study aims to use the theory of third places to understand how different kinds of social interactions in small hospitality businesses, such as restaurants and cafes, can enhance senior customers’ experiences and alleviate their loneliness.
Design/methodology/approach
The target population of this study were Hong Kong residents of age 60 or older. The sampling frame comprised respondents who visited a Cha Chaan Teng (i.e. a Hong Kong-style tea restaurant) more than once a year. The authors distributed 500 questionnaires and collected 411 valid responses in 2016. They used structural equation modeling for data analysis.
Findings
The results show that social interactions (service manner and need identification) with employees and other customers have a positive effect on senior customers’ experiences, while the service manner of employees reduces senior customers’ loneliness.
Originality/value
This study demonstrates the respective contributions of social interactions with employees and those with other customers to enhancing senior customers’ experiences and alleviating their loneliness. This study’s findings may provide a foundation for future research into the relationships between social interactions, customer experience and loneliness in third places (that are, informal public places that offer individuals opportunities to escape from home and the workplace and to enjoy voluntary conversation, entertainment and gatherings). Further, this study also demonstrates the specific role and importance of the hospitality industry in addressing a contemporary social problem in the form of seniors’ loneliness.
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Doris Chenguang Wu, Haiyan Song and Shujie Shen
The purpose of this paper is to review recent studies published from 2007 to 2015 on tourism and hotel demand modeling and forecasting with a view to identifying the emerging…
Abstract
Purpose
The purpose of this paper is to review recent studies published from 2007 to 2015 on tourism and hotel demand modeling and forecasting with a view to identifying the emerging topics and methods studied and to pointing future research directions in the field.
Design/methodology/approach
Articles on tourism and hotel demand modeling and forecasting published mostly in both science citation index and social sciences citation index journals were identified and analyzed.
Findings
This review finds that the studies focused on hotel demand are relatively less than those on tourism demand. It is also observed that more and more studies have moved away from the aggregate tourism demand analysis, whereas disaggregate markets and niche products have attracted increasing attention. Some studies have gone beyond neoclassical economic theory to seek additional explanations of the dynamics of tourism and hotel demand, such as environmental factors, tourist online behavior and consumer confidence indicators, among others. More sophisticated techniques such as nonlinear smooth transition regression, mixed-frequency modeling technique and nonparametric singular spectrum analysis have also been introduced to this research area.
Research limitations/implications
The main limitation of this review is that the articles included in this study only cover the English literature. Future review of this kind should also include articles published in other languages. The review provides a useful guide for researchers who are interested in future research on tourism and hotel demand modeling and forecasting.
Practical implications
This review provides important suggestions and recommendations for improving the efficiency of tourism and hospitality management practices.
Originality/value
The value of this review is that it identifies the current trends in tourism and hotel demand modeling and forecasting research and points out future research directions.
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Li Zhang, Haiyan Fang, Weimin Bao, Haifeng Sun, Lirong Shen, Jianyu Su and Liang Zhao
X-ray pulsar navigation (XPNAV) is an autonomous celestial navigation technology for deep space missions. The error in the pulse time of arrival used in pulsar navigation is large…
Abstract
Purpose
X-ray pulsar navigation (XPNAV) is an autonomous celestial navigation technology for deep space missions. The error in the pulse time of arrival used in pulsar navigation is large for various practical reasons and thus greatly reduces the navigation accuracy of spacecraft near the Earth and in deep space. This paper aims to propose a novel method based on ranging information that improves the performance of XPNAV.
Design/methodology/approach
This method replaces one pulsar observation with a satellite observation. The ranging information is the difference between the absolute distance of the satellite relative to the spacecraft and the estimated distance of the satellite relative to the spacecraft. The proposed method improves the accuracy of XPNAV by combining the ranging information with the observation data of two pulsars.
Findings
The simulation results show that the proposed method greatly improves the XPNAV accuracy by 70% compared with the conventional navigation method that combines the observations of three pulsars. This research also shows that a larger angle between the orbital plane of the satellite and that of the spacecraft provides higher navigation accuracy. In addition, a greater orbital altitude difference implies higher navigation accuracy. The position error and ranging error of the satellite have approximately linear relationships with the navigation accuracy.
Originality/value
The novelty of this study is that the satellite ranging information is integrated into the pulsar navigation by using mathematical geometry.