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This paper describes the results of an analysis carried out on thermally conductive and electrically conductive adhesives, in order to characterise their behaviour for electronics and telecommunications applications.

Conductive adhesives (CAs) have been with us for a number of years and have found use in a variety of applications. More recently pressure from environmentalists has led to a reappraisal of the potential of the materials to replace solders in mainstream assembly operations. In this respect they have the advantages that they do not contain lead and do not use fluxes. At present, however, there is no substitute for flow soldering operations which still account for a substantial part of the assembly market. There also appear to be serious grounds for concern regarding the reliability of adhesive joints. In particular, recent reports suggest that their resistance to mechanical shock may be unsatisfactory. In the light of these drawbacks it seems likely that CAs will continue to find niche applications, where their particular properties give them advantages, but that soldering will continue to be the dominant technology for PCB assembly for the foreseeable future.

Some essential issues about modeling of reverse logistics (RL) systems and product recovery networks include consideration of the qualities of the returned products, taking into account uncertainty and integrating the forward and reverse flows. The purpose of this paper is to develop the integrated RL model, which focuses on the control of inventory and production planning problems in a case of uncertainty in demand, quantities and qualities of returns.

The model involves a forward production route, three alternative recovery routes and a disposal route. Various levels of qualities are considered for returned products. A fuzzy mixed integer programming model (FMIP) is developed to provide a solution for the problems of production planning and inventory control. After maximizing the satisfaction degree, different solutions can have the same maximum. Moreover, policies that use all recovery routes and reduce the overall uncertainty have no chance to be chosen. To tackle these problems, a two-phase approach method is applied.

According to the results of the numerical example, using different and appropriate recovery options based on the quality of returns can significantly decrease the recovery costs. Similarly, it is shown that the two-phase approach can be an effective and efficient method to reach a satisfactory solution for such problems.

In this study, after maximizing the FMIP model, a two-phase approach ‒ as a novel optimization technique in this research ‒ is employed to achieve a desirable solution.

This paper reports on an integrated prototype expert system, which has been developed to support geotechnical engineers during the initial foundation design phase. Foundation design based on Dutch practice and geotechnical codes as well as construction and project management aspects is programmed. The paper discusses an integrated approach to foundation design of buildings using a case‐demonstration to show the proposed system and its basis. The modelling techniques used offer a sound basis for including these aspects in routine geotechnical design. The example has indicated that the system is capable of integrating geotechnical design aspects with construction related aspects in order to produce better foundation design solutions.

The purpose of this paper is to evaluate the efficiency of Algerian banks and examine the effects of explanatory factors on their performance.

In this paper, a methodology of two-stage network data envelopment analysis (DEA) is used to explore the efficiency of a sample of 13 Algerian banks during the 2013–2017 period. In the first stage, the network DEA is used to assess the overall and stages efficiencies. In the second stage, the partial least squares (PLS) regression is conducted to determine the potential effects of explanatory factors on stages efficiency.

The main empirical results indicate that Algerian banks need an efficiency improvement in both stages. The overall efficiency of the Algerian banking system improves over the study period. The deposit producing efficiency is positively affected by bank size and bank age. The revenue earning efficiency is negatively associated with bank size and bank age. The domestic banks are more efficient than foreign banks in the deposit producing stage and the foreign banks are more efficient than domestic banks in the revenue earning stage.

The results might be used as guidelines for both managers and policymakers in order to improve banks and banking system performance.

To the best of our knowledge, this study is the first that uses the DEA in investigating the efficiency of Algerian banks by dividing the overall efficiency into deposit producing and revenue earning efficiencies. Unlike most studies that have usually used OLS regression, Tobit regression and bootstrapped truncated regression, this study is the first in the bank efficiency literature that uses PLS regression to investigate the potential effect of explanatory variables on deposit producing and revenue earning efficiencies.

In order to answer which opportunities are better to pursue, the purpose of this paper is to propose and empirically test a decision-making model for evaluating and selecting entrepreneurial opportunities.

First, the authors identified common evaluation criteria through a systematic review of 45 high quality articles published in top entrepreneurship and management journals between 2000 and 2017. Second, fuzzy screening technique has been employed to offer the decision-making model. Third, the authors used data of six evaluations provided by five experts at a medium-sized biotech firm to test the model.

The study shows that common decision criteria for evaluating entrepreneurial opportunities fall into seven categories. According to these criteria and using fuzzy screening technique, a multi-expert multi-criteria decision-making (ME–MCDM) model has been suggested for evaluating and selecting opportunities.

This model can be served in situations in which decision makers should select a small number of opportunities among the larger set with regard to opportunity profile and minimal information. More opportunities and more decision makers can be included in the model. When the number of opportunities and decision makers are high, it is possible to use programming for fast, accurate and easy calculation.

This study is the first systematic review of opportunity evaluation criteria. It is also the first considering opportunity evaluation as a multi-expert decision-making process.

In this study, the authors examine the push and pull effects of extreme weather events on migration among governorates in Egypt.

To estimate the effect of extreme weather events on internal migration, the authors use migration gravity models and data from the 1996 and 2006 Population and Housing Censuses. The authors measure weather extremes by the number of months in the past 36 months with temperatures or precipitation of a governorate below the 5th percentile and above the 95th percentile of the distribution of monthly temperatures or precipitation of the corresponding governorate during the period 1900–2006.

This study’s results suggest that high temperatures in the origin area act as a push factor. High-temperature extremes have a positive effect on out-migration. A 1% increase in the number of months with high-temperature extremes in the original governorate results in a 0.1% increase in the number of out-migrants.

The study suggests that people may respond to weather extremes through migration. However, climate migrants in Egypt may encounter several significant risks that authorities must address.

This study is one of the first attempts to measure the push and pull effect of weather extremes on migration in Egypt.

The purpose of this paper is to identify and develop a hierarchy of corporate social responsibility (CSR) dimensions and their interrelationships using interpretive structural modelling (ISM) methodology.

This research used ISM for framework development. ISM is, however, a sound method for developing insight into the collective understanding of the relationships between dimensions of corporate social responsibility (CSR) identified from the literature review. The steps involved in the ISM technique are structural self-interaction matrix, reachability matrix, level partitions, developing the canonical matrix, classification of dimensions for CSR and formation of ISM.

The findings indicate that company size is the only key driver for the other dimensions of CSR and is hence placed at the very bottom of the ISM model. Above this, at Level II, the key dimensions are corporate governance, diversity and corporate profile. These act as mediating dimensions between company size and the topmost level (i.e. Level III), which comprises 15 dimensions including CSR.

Some limitations of this research indicate the need for further research. First, the proposed ISM model has only been conceptualised and has not been empirically tested using primary data. Future research is needed to validate the model in whole or part, to understand the perceived CSR of a company. Second, the methodology was limited to the use of ISM to model the CSR dimensions; it was not extended to fuzzy MICMAC analysis or to interpretive ranking.

The proposed ISM-based model for the identification and ranking of CSR dimensions and their interrelationships offers decision makers and practitioners a more convincing representation of the problems affecting the exploration of CSR dimensions. The utility of the proposed ISM method lies in imposing order and direction on the complexity of relationships among these dimensions, which will help top management and decision makers to better use their available resources in optimising their CSR practices. The framework allows policymakers to effectively incorporate these dimensions into their practising of CSR.

This is the first research on CSR to conceptualise a framework of causal interactions among its key dimensions using ISM methodology.

The purpose of this paper is to describe an extension of the boundary element method (BEM) and the dual reciprocity boundary element method (DRBEM) formulations developed for one- and two-dimensional steady-state problems, to analyse transient convection–diffusion problems associated with first-order chemical reaction.

The mathematical modelling has used a dual reciprocity approximation to transform the domain integrals arising in the transient equation into equivalent boundary integrals. The integral representation formula for the corresponding problem is obtained from the Green’s second identity, using the fundamental solution of the corresponding steady-state equation with constant coefficients. The finite difference method is used to simulate the time evolution procedure for solving the resulting system of equations. Three different radial basis functions have been successfully implemented to increase the accuracy of the solution and improving the rate of convergence.

The numerical results obtained demonstrate the excellent agreement with the analytical solutions to establish the validity of the proposed approach and to confirm its efficiency.

Finally, the proposed BEM and DRBEM numerical solutions have not displayed any artificial diffusion, oscillatory behaviour or damping of the wave front, as appears in other different numerical methods.

The purpose of this study is to propose a multidimensional view of social innovation.

It offers a detailed analysis of the activities performed by ADEL (Agência de Desenvolvimento Econômico Local) – a regional non-governmental organization located in one of the poorest regions of Brazil – which is succeeding in engaging young people in the promotion of local development. The case was analysed drawing on the dimensions structured by researchers of one of the main centres of social innovation in the world, the Centre de Recherche sur Les Innovations Sociales (CRISES) based in Canada.

The results found characterize ADEL as a social innovation based on the dimensions of social innovation described in the CRISES’ conceptual encyclopaedia (Tardif and Harrison, 2005). The results highlight the singularities of the case studied, which allowed the elaboration of a revisited table of dimensions proposed by the CRISES’ researchers.

For future studies, using the CRISES’ table as reference of analysis for other social innovations, the possibility suggested is the quantitative exploration of these dimensions.

The originality of this article lies in the fact that it presents a representative social innovation for the Brazilian semiarid.