Search results

Battery electric vehicles (BEVs) are living up to their claims as consumers choose them more frequently. The increasing demand for sustainable vehicles translates into the global need for specific components, materials, and infrastructures and drives the regulatory frameworks in each country. While BEVs offer environmental benefits and global business opportunities, the technology has not yet gained mainstream acceptance. Thus, this work aims to investigate the characteristics of BEV users and their role in the diffusion of products to larger segments, as this may vary from country to country. For this purpose, a survey based on the Unified Theory of Acceptance and Use of Technology 2 (UTAUT-2) (Venkatesh et al., 2012) framework and structural equation modeling (SmartPLS) was adopted. The results indicated that, except for the constructs of effort expectancy (EE) and social influence (SI), the predictors in the model performed well in this context. Current users are satisfied with their vehicles and are supportive of BEVs in the future. The analysis also revealed that in addition to the availability of financial resources, early adopters are attracted by new technologies in a way that leads them to make decisions outside of the traditional influence of the other members of society. It is suggested to leverage the perceived benefits of status, differentiation, or uniqueness motives, to appeal to those seeking to appear trendy and tech-savvy in society. Companies and policymakers should acknowledge the peculiarities of early customers in their communication strategies to reach a wider audience around the globe and encourage the adoption of BEV technology.

This paper presents the defects that occur during the assembly and manufacturing of solder joints in single‐sided insertion‐mount printed wiring boards (PWBs). Each type of defect is discussed, with particular focus on how these defects are related to solderability issues, the mechanisms of failure due to defect‐induced failure accelerators, and the effect of the defect on solder joint reliability.

The aim of this paper is twofold. The main objective is to contribute to a more comprehensive understanding of the tensions that characterize social enterprises because of their dual (economic and social) commitments in a Hungarian context.

The research was exploratory, as no structured inquiry has been carried out in a Hungarian context concerning the sources of tension social enterprises encounter because of their dual commitments. Therefore, a qualitative approach was chosen to achieve the exploratory goal. Semi-structured in-depth interviews were carried out with one expert and nine social entrepreneurs to map and understand these tensions in a Hungarian context.

The research provides a comprehensive three-level model of tensions in which concrete (observable) tensions are grouped into 4 main groups of tensions and 15 subgroups.

This study is original in two ways. First, besides the numerous tensions other researchers have already observed, this study revealed some that have not been empirically observed. Second, being the first research on tensions in a Hungarian context, to the best of the authors’ knowledge, the results increase understanding of social entrepreneurship in a Hungarian context based on the lived experiences of Hungarian social entrepreneurs.

This paper aims to understand the difficulties faced by Latin American oil and gas (O&G) companies in adopting integrated practices aligned with the UN Sustainable Development Goals (SDG) Agenda.

A Delphi study was conducted with 14 experts with extensive knowledge and experience in the O&G sector to collect opinions and investigate sustainable practices in the Latin American context.

A consensus was reached after two rounds, demonstrating a unified view of sustainability experts on the difficulties faced by O&G companies to adopt practices aligned with the SDGs. The difficulties identified through the Delphi method were allocated into five clusters named: “public sector and governments,” “civil society,” “corporate issues,” “technology and innovation” and “financial aspects.” These clusters were used to discuss the main challenges associated with implementing business practices that recognize the SDGs and their achievement as a synergistic reinforcing system rather than an additive structure.

This study provides further insights into the underexplored subject relating to the challenges experienced by Latin American O&G companies in the implementation of the SDGs, adopting the perspective of academic and industry experts in this field. The findings can help professionals in O&G companies implement sustainable practices, policymakers in debates about futures laws and regulations and academic in future research.

Health literate discharge practices meet patient and family health literacy needs in preparation for care transitions from hospital to home. The purpose of this paper is to measure health literate discharge practices in Ontario hospitals using a new organizational survey questionnaire tool and to perform psychometric testing of this new survey.

This survey was administered to hospitals in Ontario, Canada. Exploratory factor analysis and reliability testing were performed.

The participation rate of hospitals was 46 percent. Exploratory factor analysis demonstrated that there were five factors. The survey, and each of the five factors, had moderate to high levels of reliability.

There is a need to expand the focus of further research to examine the experiences of patients and families. Repeating this study with a larger sample would facilitate further survey development.

Measuring health literate discharge practices with an organizational survey will help hospital managers to understand their performance and will help direct quality improvement efforts to improve patient care at hospital discharge and to decrease hospital readmission.

There has been little research into how patients are discharged from hospital. This study is the first to use an organizational survey tool to measure health literate discharge practices.

The purpose of this paper is to propose an alternative test board design with only one loading condition and sufficiently large sample size, which is more suitable for the statistical package qualification. With the exception of the board shape and size and package component layout, all other aspects of the design strictly follow the JEDEC standard so that the board design can be easily implemented.

A test board in a round shape was introduced. First, drop tests were carried out. Then, the dye stain test and metallurgical analysis were performed in order to study the failure mechanism of lead‐free solder joint under drop impact.

The test results indicate that the combined effect of mechanical shock and PCB bending vibration is the root cause of solder joint failure under drop impact, and that the maximum peeling stress of the critical solder joint could be considered to be the dominant failure factor. On the other hand, the fracture of BGA lead‐free solder joints occurs at intermetallic compound (IMC) interface near the package side, and failure mode is brittle fracture.

These results are the same as those of JEDEC standard test board. Furthermore, the solder joint loading conditions in this design are simplified from six to one. The round test board can take the place of JEDEC standard test board to carry out drop test and to enable good solder joint life prediction and statistical analysis.

For numerical treatment of resin‐containing systems and forecasting of their properties, certain models of branching are needed. In this review, existing theoretical models of systems containing branched structures (polymers, aggregates, etc.) are analyzed and compared. The criteria of selection of the optimal theoretical model comprise chemical and physical problems available for solution, simplicity of such solution, connection between theoretically forecasted and experimental results, and the time needed for computing. It is concluded that, according to these criteria, the optimal (between existing models) is the statistical polymer method.

The purpose of this paper is to discuss a new method to measure the fatigue of single solder joints in shear, and hence calculate the joint strain energy density in each fatigue cycle.

There has been a step change in the requirement to characterise solder joint reliability with the number of new alloys introduced as a result of the recent RoHS legislation. Experimental testing for every configuration is expensive and time consuming, and hence modelling has become more attractive. The accuracy of modelling predictions is limited by the accuracy of the materials data. The data for these new alloys must reflect the miniaturisation of electronics and that solder joints are loaded in shear, two aspects not well reflected in the existing SnPb data. The approach here has been to develop an instrument interconnect properties test machine, where the strain and stress can be measured directly for small solder volumes and in shear. A four‐point measurement system for resistance monitoring has also been evaluated and found to correlate well with load decreases recorded during fatigue testing of solders, and hence provide a method to calculate the crack area.

The experiments have recorded the stress strain behaviour during isothermal fatigue. The developing crack area has been measured using an electrical resistance technique and has been used to correct the stress values. Using the corrected stress the strain energy data can be calculated.

The work has been limited to a single alloy and a single joint configuration, with time these will be broadened and the experimental fatigue parameters extended.

These measurements will provide a route for calibrating the finite element models. A databank of material properties could be built up for alloys used in a range of configurations. This would help support and widen the use of modelling to predict fatigue life.

There is an increasing awareness of the importance of measuring microelectronic solder joint fatigue properties. There are a number of approaches being pursued, but the work at NPL is important in allowing the experiment to be controlled by either stress, strain or temperature, and with the added ability to measure crack area. This uniquely enables the measurement directly of the strain energy density during a fatigue experiment.