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This study aims to investigate soldering of SiC ceramics by using Zn-Al-In-based solders and ultrasonic soldering. The focus was on the quality of soldered joints, examining the boundary of the solder/substrate joint and the strength of the fabricated joints. Moreover, the fractured surfaces of joints were assessed.

The Zn-5Al base, which is considered for eutectic solder, was used in experiments. When manufacturing this solder, In was also added to at 1 Wt.%. The soldering of SiC substrates on a hot plate with ultrasonic assistance was performed.

The solder at room temperature consists of a primary segregated solid solution (Zn) and the binary eutectics (Zn) + (Al) with a high Al content and binary lamellar eutectic with a high Zn and In content non-uniformly distributed on the grain boundaries. The average tensile strength of the Zn5Al1In solder was 52 MPa. The ceramic material was wetted during soldering via reaction between the solder and the SiC substrate, with the formation of Al-Si reaction products. The thickness of the reaction layer on the boundary was 0.5–1.1 µm. The average strength of the soldered joint was 59 MPa. The obtained results confirmed the high efficiency of ultrasonic soldering in air.

This work has characterised Zn5Al1In soldering alloy and examining soldering SiC ceramics by a flux-less ultrasonic process. The analyses were oriented to assess the strength and structure of the solder and the soldered joints. Based on the achieved results, it is possible to predict the suitability of the solder alloy for flux-free soldering of SiC ceramics.

This study aims to solder AlN ceramics with a Cu substrate using an active type Sn-Ag-Ti solder. Soldering was performed with power ultrasound. The Sn3.5Ag2Ti alloy was first studied.

It was found to contain a Sn matrix, where both Ag phase – ɛ-Ag₃Sn – and Ti phases ɛ-Ti₆Sn₅ and Ti₂Sn₃ – were identified. Ti contained in these phases is distributed to the interface with ceramic material. A reaction layer was thus formed. This layer varies in thickness from 0.5 to 3.5 µm and ensures the wettability of an active solder on the surfaces of ceramic materials.

X-ray diffraction analysis proved the presence of new NTi and AlTi₂ phases on the fractured surface. Sn plays the main role in bond formation when soldering the Cu substrate with Sn-Ag-Ti solder. The Cu₃Sn and Cu₆Sn₅ phases, which grow in direction from the phase interface to solder matrix, were found in all cases within the solder/Cu substrate interface. The combination of AlN ceramics/Cu joint maintained a shear strength of 29.5 MPa, whereas the Cu/Cu joint showed a somewhat higher shear strength of 39.5 MPa.

The present study was oriented towards soldering of AlN ceramics with a Cu substrate by the aid of ultrasound, and the fluxless soldering method was applied. Soldering alloy type Sn-Ag-Ti was analysed, and the interactions between the solder and ceramic and/or Cu substrate were studied. The shear strength of fabricated soldered joints was measured.

The Canadian mutual fund setting is unique in that two governance mechanisms – corporate and trust – coexist. This study empirically examines the impact of each mechanism on fund fees and performance. We find that corporate class funds charge higher fees but deliver superior fee-adjusted returns than trust funds. We then analyze the impact of various board characteristics on fees and performance for corporate class funds. We find that a board with smaller size, CEO duality, and a higher percentage of independent directors is more likely to charge lower fees. In addition, smaller boards are strongly associated with higher fee-adjusted performance. Our study supports agency theory over stewardship theory and provides valuable guidelines for Canadian investors and regulatory agencies.

The work aims to study the direct bonding of silicon substrate with solders type Sn-Ag-Ti.

During the bonding process with ultrasound assistance, the active element (Ti,Ce,Mg) is distributed from the solder to interface with a silicon substrate, where it supports the bond formation.

Formation of a reaction layer, 1-2 μm in thickness, was observed. The new Si2Ti phases and Mg2Si phase were identified in the reaction layer.

The results of analysis suggest that the Si/Sn-Ag-Ti joint is of diffusion character. The highest average strength on silicon substrate (39 MPa) was achieved with Sn-Ag-Ti(Mg) solder.

Circular economy (CE) has gained considerable attention from researchers and practitioners over the past few years because of its potential social and environmental benefits. However, limited attention has been given in the literature to explore the drivers and barriers in CE implementation in emerging and developing countries besides China. Therefore, the purpose of this paper is to identify the drivers and barriers to implementing a CE in Pakistan’s automobile manufacturing industry.

This study adopts an explorative approach to understand the drivers and barriers at the micro-level CE implementation in Pakistan’s automobile industry. The research design includes both qualitative and quantitative methods using a survey instrument and interviews to gather data. The use of the two main sources of data provides the opportunity for triangulation of the data to improve the validity of the findings, and enables greater inferences from the results.

This study shows that “profitability/market share/benefit” (30 percent), “cost reduction” (22 percent) and “business principle/concern for environment/appreciation” (19 percent) are the top three drivers. Similarly, “unawareness” (22 percent), “cost and financial constraint” (20 percent) and “lack of expertise” (17 percent) are the top three barriers in implementing CE principles in Pakistan automobiles industry.

This study considers only Pakistan automobiles industry, and the practical implications potentially limit to emerging Asian economies.

This study is the first of its kind that has investigated the drivers and barriers of CE at the organizational level in the automobile industry of Pakistan. Thus, it helps to advance the understanding of the subject matter and enables the formulation of effective policies and business strategies by practitioners for upscaling CE and sustainability.

The purpose of this paper is to examine the relationship between neighbourhood characteristics and fear of crime, and further explore how this relationship is mediated by collective efficacy. The background to this is that while research, mainly based on the experiences of western countries is conclusive on how collective efficacy plays a mediating role between neighbourhood structural characteristics and fear of crime, the situation in developing countries remains poorly researched.

The study drew from a baseline survey conducted in different socio-economic neighbourhoods in four cities in Ghana. With regards to the analysis, results from a series of ordinary least square multiple regression models were used to develop a path diagram to explain the direct and indirect relationships at the various study neighbourhoods.

Results from the study showed variations of the extent of neighbourhood effect on fear of crime and collective efficacy in the different socio-economic neighbourhoods. More importantly, the study revealed that collective efficacy mediated the effect of a number of neighbourhood characteristics on fear of crime in low-income neighbourhoods compared to middle- and high-income neighbourhoods.

The conclusion of the study brings to the fore the relevance of collective efficacy as a vehicle for building safer communities in Ghana since it relies on local initiatives in addressing criminogenic problems. More importantly, it is suggested that formal crime prevention efforts should be integrated with informal crime control measures, particularly in low-income neighbourhoods.

Using extensive survey data collected in Ghana, the study examines the applicability of collective efficacy, a western-based socio-ecological theory in a developing country context.

The aim of this study is to identify and prioritize a list of key digitization enablers that can improve supply chain management (SCM). SCM is an important driver for organization's competitive advantage. The fierce competition in the market has forced companies to look the past conventional decision-making process, which is based on intuition and previous experience. The swift evolution of information technologies (ITs) and digitization tools has changed the scenario for many industries, including those involved in SCM.

The Best Worst Method (BWM) has been applied to evaluate, rank and prioritize the key digitization and IT enablers beneficial for the improvement of SC performance. The study also used additive value function to rank the organizations on their SC performance with respect to digitization enablers.

The total of 25 key enablers have been identified and ranked. The results revealed that “big data/data science skills”, “tracking and localization of products” and “appropriate and feasibility study for aiding the selection and adoption of big data technologies and techniques ” are the top three digitization and IT enablers that organizations need to focus much in order to improve their SC performance. The study also ranked the SC performance of the organizations based on digitization enablers.

The findings of this study will help the organizations to focus on certain digitization technologies in order to improve their SC performance. This study also provides an original framework for organizations to rank the key digitization enablers according to enablers relevant in their context and also to compare their performance with their counterparts.

This study seems to be the first of its kind in which 25 digitization enablers categorized in four main categories are ranked using a multi-criteria decision-making (MCDM) tool. This study is also first of its kind in ranking the organizations in their SC performance based on weights/ranks of digitization enablers.

In response to the growing evidence that disruptive behaviors within health care teams constitute a major threat to the quality of care, the Joint Commission on Accreditation of Healthcare Organization (JCAHO; Joint Commission Resources, 2008) has a new leadership standard that addresses disruptive and inappropriate behaviors effective January 1, 2009. For professionals who work in human resources and organization development, these standards represent a clarion call to design and implement evidence-based interventions to create health care communities of respectful engagement that have zero tolerance for disruptive, uncivil, and intimidating behaviors by any professional. In this chapter, we will build an evidence-based argument that sustainable change must include organizational, team, and individual strategies across all professionals in the organization. We will then describe an intervention model – Toxic Organization Change System – that has emerged from our own research on toxic behaviors in the workplace (Kusy & Holloway, 2009) and provide examples of specific strategies that we have used to prevent and ameliorate toxic cultures.

This study aims to investigate the impact of female chairperson, female chief executive officer and presence of females on boards on listed firms’ profitability using data from Ghana.

This study used ordinary least square estimation and generalized least square (i.e. fixed and random effect estimation techniques) estimation on the data of 15 nonfinancial listed firms on Ghana Stock Exchange between 2010 and 2020.

The results show that while males dominate corporate executive positions in listed nonfinancial firms in Ghana, females serving in top corporate executive positions like chief executive officer, board chairperson and female board membership positively impact listed firms’ performance in the form of return on assets, net profit margin and gross profit margin. These findings are consistent even when year and industry effects are controlled for. This suggests that enacting policies at the national and firm levels to encourage female participation in corporate executive roles/positions are critical for promoting firm performance.

This study extends extant empirical literature on the economic role of female executives in firm performance from the developing context of Ghana. With calls in literature for more studies on the subject matter in varied contexts and conditions, this study takes the discussion a step further by investigating whether the gender of those in positions such as board chairperson and chief executive officer matters in firm profitability in Ghana.