Abstract
Purpose
The purpose of this paper is to study the melting temperature of the nanoparticles of the new developed Sn‐0.4Co‐0.7Cu (wt%) lead‐free solder alloy.
Design/methodology/approach
Nanoparticles of Sn‐0.4Co‐0.7Cu lead‐free solder alloy were prepared by the self‐developed consumable‐electrode direct current arc technique, where ultrasonic vibration was applied during the manufacturing of the particles. X‐ray diffraction and field emission scanning electron microscope were employed to analyze the crystal structure and morphology of the nanopartiles, respectively. Differential scanning calorimetry was used to investigate the melting temperature of both the bulk alloy and as‐prepared nanoparticles.
Findings
The melting temperature of the nanoparticles was approximately 5°C lower compared to that of the bulk alloy.
Originality/value
As a novel developed lead‐free solder alloy, the Sn‐0.4Co‐0.7Cu (wt%) alloy provides a cost advantage compared to the extensively used Sn‐Ag‐Cu system. Some limitations still exist, however, mainly due to its relatively higher melting temperature compared to that of eutectic Sn‐37Pb solder. In view of this situation, the attempt to lower its melting temperature has recently attracted more attention based on the knowledge that the melting temperature for pure metals is reduced when the particle size is decreased down to a few tens of nanometers.
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Akram Al-Turk and Howard E. Aldrich
In this chapter, the authors investigate the degree to which organizational ecology (OE) had a long-term impact on the way scholars study organizational foundings. Dubbed the…
Abstract
In this chapter, the authors investigate the degree to which organizational ecology (OE) had a long-term impact on the way scholars study organizational foundings. Dubbed the “rates” approach by Aldrich and Weidenmayer (1993), OE argued that organizational foundings depend on intra- and inter-population processes such as organizational density, prior foundings, and prior disbandings. It de-emphasized the personal characteristics of founders and entrepreneurs – the “traits” approach. The analyses reveal that OE had limited impact, especially after the mid-2000s. OE’s limited appeal is partially explained by its lack of influence on scholars outside its orbit of influence and/or those publishing in non-sociology journals. In contrast to OE’s slight long-term impact, the authors argue that another perspective that was attuned to environmental conditions – new institutional theory (NIT) – has had greater success in influencing scholars studying foundings. The authors speculate that OE’s impact was ultimately limited because it was embedded in a relatively exclusive scholarly community, compared to NIT’s more inclusive scope.
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Oscar Javier Montiel Méndez, Rosa Azalea Canales García and Oscar Alejandro Vásquez Bernal
Entrepreneurship is a key factor in the growth of regions, given its impact on innovation and job creation. The relationship between start-up companies and their environment is…
Abstract
Entrepreneurship is a key factor in the growth of regions, given its impact on innovation and job creation. The relationship between start-up companies and their environment is closely linked to negotiation mechanisms since the formation of trust, the governance structure, and how entrepreneurs protect themselves from adverse situations depend on them. However, no single framework can bring together the bargaining, entrepreneurship, and institutional factors that determine the success or failure of start-ups. The objective of this chapter is to jointly analyze bargaining and entrepreneurship through the theory of economic institutionalism, Transaction Cost Theory, and Cognitive Organization Theory. To this end, an analytical scheme is proposed that brings together these precepts applied theoretically to the Latin American case. The scope is to provide a novel framework of analysis by incorporating essential institutional elements for negotiation, such as contracting, governance, organizational structure, trust, relational risks, and hedging against opportunism.
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Pedro Lucas de Resende Melo, Felipe Mendes Borini, Victor Ragazzi Isaac and Victor Silva Correa
The purpose of this paper is to understand and identify the various characteristics of the institutional environment and the factors that propitiate the attraction of franchise…
Abstract
Purpose
The purpose of this paper is to understand and identify the various characteristics of the institutional environment and the factors that propitiate the attraction of franchise chains to cities in the interior, using Brazil as an analysis.
Design/methodology/approach
Secondary data from the Brazilian Institute of Geography and Statistics were used. It comprised a sample of 1,683 Brazilian cities with commercial outlets featuring franchise brands. It was limited to cities with populations of up to 100,000 inhabitants that did not constitute metropolitan regions. The statistical technique performed was multiple regression.
Findings
The results of the multiple regression confirm the explanatory power of R² = 36% for the analyzed model. Such presence of franchise chains is based on four institutional dimensions and their environmental characteristics: demographic (demographic density); economic and financial (average monthly salary of formal workers and number of banking agencies); business (number of active companies and presence of shopping centers); and human resources (presence of higher education units).
Research limitations/implications
The main contribution of the study encompasses the call that regional institutional characteristics are part of knowledge guidelines on regional development and institutional environments for entrepreneurship. In this sense, the paper contributes to studies on regional development in particular, by punctuating the characteristics of the institutional environment of cities that are related to the existence of franchise chain brands.
Practical implications
Such contributions are addressed to managers and directors of expanding franchise chains, given the choice of locations that best enable the concept of their franchises. The fact that only 20% of franchises have a presence in these cities, even if it is admitted that for 70% of these chains, their businesses have the capacity to make these locations viable, shows the importance of this contribution.
Social implications
This study is addressed to public managers, represented by secretaries of municipal developments, in view of the construction of an institutional environment conducive to entrepreneurial activity, in this specific case, by franchises. It is an important mechanism for attracting new businesses and creating a virtuous cycle of regional development.
Originality/value
Specifically, knowledge is generated about the insertion of ventures based on the franchise business model in small- and medium-sized regional markets. A second feature involves the understanding of the insertion of enterprises in a large and heterogeneous emerging market.
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Jian Li, Xinlei Yan, Feifei Zhao and Xin Zhao
The purpose of this paper is to solve the problem that the location of the initiation point cannot be measured accurately in the shallow underground space, this paper proposes a…
Abstract
Purpose
The purpose of this paper is to solve the problem that the location of the initiation point cannot be measured accurately in the shallow underground space, this paper proposes a method, which is based on fusion of multidimensional vibration sensor information, to locate single shallow underground sources.
Design/methodology/approach
First, in this paper, using the characteristics of low multipath interference and good P-wave polarization in the near field, the adaptive covariance matrix algorithm is used to extract the polarization angle information of the P-wave and the short term averaging/long term averaging algorithm is used to extract the first break travel time information. Second, a hybrid positioning model based on travel time and polarization angle is constructed. Third, the positioning model is taken as the particle update fitness function of quantum-behaved particle swarm optimization and calculation is performed in the hybrid positioning model. Finally, the experiment verification is carried out in the field.
Findings
The experimental results show that, with root mean square error, spherical error probable and fitness value as evaluation indicators, the positioning performance of this method is better than that without speed prediction. And the positioning accuracy of this method has been improved by nearly 30%, giving all of the three tests a positioning error within 0.5 m and a fitness less than 1.
Originality/value
This method provides a new idea for high-precision positioning of shallow underground single source. It has a certain engineering application value in the fields of directional demolition of engineering blasting, water inrush and burst mud prediction, fuze position measurement, underground initiation point positioning of ammunition, mine blasting monitoring and so on.
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Yifan Zhang, Jianyang Zhu, Xu Wang, Yaochi Zhang and Le Gu
Under oil interruption, lubricant supply in the high-speed bearing cavity is interrupted, which reduces the bearing lubrication and cooling ability, thus leading to degradation of…
Abstract
Purpose
Under oil interruption, lubricant supply in the high-speed bearing cavity is interrupted, which reduces the bearing lubrication and cooling ability, thus leading to degradation of bearing performance or even its failure. This paper aims to study the effect of grooves at the noncontact outer ring area on the flow and thermal performance of high-speed bearings under oil interruption, which is expected to improve the resistance of existing bearings to oil interruption.
Design/methodology/approach
The groove was added to the noncontact outer ring area of the bearing, and a method of combining volume of fluid and MRF was adopted to systematically study and analyze the oil-gas flow field structure and the temperature field distribution in the bearing cavities.
Findings
Results show that the lubricating oil could be stored and guided by the grooves of the bearing outer ring into the key lubrication area inside the bearing cavity, which increased the oil content near the inner ring and made the oil distribution more uniform. As a result, lubrication cooling and heat dissipation performance of the bearing cavity was improved. Compared with the original bearing, the bearing with a V-shaped groove had the optimal lubrication and cooling performance.
Originality/value
A rolling bearing model of the noncontact outer ring area with grooves under oil interruption is established in the paper. The simulation results provide theoretical guidance for the research and development of high-speed bearings with stronger oil interruption resistance ability.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-06-2024-0199/
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Xieling Chen, Shan Wang, Yong Tang and Tianyong Hao
The purpose of this paper is to explore the research status and development trend of the field of event detection in social media (ED in SM) through a bibliometric analysis of…
Abstract
Purpose
The purpose of this paper is to explore the research status and development trend of the field of event detection in social media (ED in SM) through a bibliometric analysis of academic publications.
Design/methodology/approach
First, publication distributions are analyzed including the trends of publications and citations, subject distribution, predominant journals, affiliations, authors, etc. Second, an indicator of collaboration degree is used to measure scientific connective relations from different perspectives. A network analysis method is then applied to reveal scientific collaboration relations. Furthermore, based on keyword co-occurrence analysis, major research themes and their evolutions throughout time span are discovered. Finally, a network analysis method is applied to visualize the analysis results.
Findings
The area of ED in SM has received increasing attention and interest in academia with Computer Science and Engineering as two major research subjects. The USA and China contribute the most to the area development. Affiliations and authors tend to collaborate more with those within the same country. Among the 14 identified research themes, newly emerged themes such as Pharmacovigilance event detection are discovered.
Originality/value
This study is the first to comprehensively illustrate the research status of ED in SM by conducting a bibliometric analysis. Up-to-date findings are reported, which can help relevant researchers understand the research trend, seek scientific collaborators and optimize research topic choices.
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Tiantian Liu, Keith Walley, Geoff Pugh and Paul Adkins
The purpose of this study is to generate insight into the effects of entrepreneurship education in China by conducting a preliminary scoping study of the enterprising tendency of…
Abstract
Purpose
The purpose of this study is to generate insight into the effects of entrepreneurship education in China by conducting a preliminary scoping study of the enterprising tendency of university students studying business.
Design/methodology/approach
This study used a self-administered questionnaire based on the General Measure of Enterprising Tendency v2 (GET2) test to measure the enterprising tendency of a group of Chinese university students. Decision trees, using the Chi-square automatic interaction detector (CHAID) approach, and multiple regression analyses were used to investigate the enterprising tendency of respondents.
Findings
The findings from this study indicate that the students have an overall medium level of enterprising tendency and strengths in some enterprising characteristics. The findings reveal that gender, family business, hometown and entrepreneurship education are significantly related to enterprising tendency but that age, household income, parents’ education and occupation are not.
Research limitations/implications
Although the study is based on a relatively small sample taken from just one university in Beijing, the findings suggest that the enterprising tendency of students can be encouraged by entrepreneurship education. Combined with evidence that entrepreneurship education is at a relatively early stage of development in China, this finding suggests considerable scope to increase student’s enterprising tendency by extending, creating a more favourable environment for and improving the methods used to deliver entrepreneurship education. Enterprising tendency can be argued to naturally result in entrepreneurial intention; however, this extension is beyond the scope of this study, which is restricted to the analysis of enterprising tendency.
Originality/value
This study makes an original contribution to knowledge as it is one of the first studies to explore enterprising tendency among university students in China. It has value for government, policymakers and university program designers in that it provides direction for entrepreneurship education in China.
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Nelson A. Andrade-Valbuena, Jose M. Merigo-Lindahl and Sergio Olavarrieta S.
The remarkable concept of entrepreneurial orientation (EO) has attracted scholars’ attention for its relevance to a firm’s performance. Based on bibliometric and distance-based…
Abstract
Purpose
The remarkable concept of entrepreneurial orientation (EO) has attracted scholars’ attention for its relevance to a firm’s performance. Based on bibliometric and distance-based visualization of similarities (VOS) analysis, the purpose of this paper is to outline a broad-spectrum perspective of the structure of research in EO across more than 20 years of publications, identifying the most prominent journals, authors and articles in this field.
Design/methodology/approach
The paper uses the Web of Science Core Collection and the VOS viewer software. The analysis searches for all the documents connected to EO available in the database from 1976 to 2017. The graphical visualization maps the bibliographic data using both bibliographic coupling and co-citation data.
Findings
Entrepreneurship Theory and Practice Journal, Journal of Business Venturing and Family Business Review are the most relevant journals in the field. Among the many important authors in the EO literature, key contributors are Lumpkin, Payne, Short, Covin, Dess and Wiklund. Three different streams of research are linked to the EO concept; strategy and entrepreneurship, family business and miscellaneous work in psychometrics, methods, marketing and knowledge/capability-based approaches to organizations.
Originality/value
This paper contributes to EO research by providing a global perspective on the concept’s investigation, using bibliometric data and graphical networks.