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The ‘lowest‐price wins’ philosophy has been a consistent theme of contractor selection over the years. To comprehensively elucidate this selection preference and compare it with the use of a multi‐criteria selection (MCS) approach in the tenderer evaluation process, this paper investigates MCS tender price selection preferences. That is, project‐specific criteria (PSC) and lowest‐price wins selection practices of UK construction clients, in both building and civil engineering works at in detail via results of the empirical survey. The investigation provides further insight into the evaluation of contractors' attributes (i.e. PSC). Levels of importance assigned (LIA) for each criterion were analysed (i.e. quantitative analysis of the differences in opinions and, variance amongst the respondents) in a multivariate statistical method. Importance attached by construction clients to the ‘lowest‐price wins’ philosophy is also presented. Contrast was made between the MCS approach and the ‘lowest‐price wins’ option amongst the surveyed construction clients. It was found that increased awareness of the use of PSC prevailed amongst the survey construction clients. This indicated that cost has to be tempered with the evaluation of PSC and the attempt of construction clients searching for a new evaluation paradigm (i.e. adoption of MCS approach rather than basing on the lowest‐price wins alone).

The purpose of this study was to investigate the changes in solder joint stress when subjected to mechanical bending. The analytical theory pertaining to the stresses in the solder joint between the components (including the molding compound, the chip and the substrate) was described, and the printed circuit board (PCB) with a discontinuity function when the PCB assembly is subjected to mechanical bending was developed. Thus, the findings reported here may lead to a better understanding of the solder joint failure based on the Physics of Failure model.

This paper discusses the analytical model for calculating the stress in solder joints, as well as presents a simulation model that can be used for calculating the strain energy density of solder joint. First, the multilayer plate theory is used in discussing the composite material for the component, including the molding compound, the silicon chip and the substrate, or the PCB, including the copper layers, the fiber and the epoxy. Finally, the complete structure of the analytical model developed as a part of this current work is presented.

For the analytical model of multilayer structures in which the interconnection layer is discrete, mechanical bending has been modeled with respect to varying silicon chip length. The analytical model that describes the stress of the outermost solder joint experiences is chosen, as this is the typical solder joint failure. The analytical model can be applied to discrete solder joints, which are evaluated by calculating the matrix form. Owing to its use of the matrix equation, the analytical model can be highly combinatorial and thus more capable of calculating the solution.

The analytical solution based on a simple concept was presented and validated using the finite element model for the stress experienced by solder joints subjected to mechanical bending. To verify that the simulation represents a real PCB case, the authors use the finite element method (FEM) to compare their case with the multilayer plate theory. Owing to the good agreement between the theory and simulation results, the authors conclude that the multilayer plate theory can be correctly applied in multilayer PCB and be used in an analytical model for the PCB assembly subjected to mechanical bending.

Owing to the good agreement between the theory and simulation results, the authors conclude that the multilayer plate theory can be correctly applied in multilayer PCB and be used in an analytical model for the PCB assembly subjected to mechanical bending.

The analytical model is validated with the FEM model and provides the way to physically examine the solder joint failure mechanism. In this paper, the analytical model is developed as a means to assess the solder joint stress subjected to mechanical bending.

The analytical model treats the solder joint as discrete and has been successfully validated against the finite element model. The complete structure model (the second analytical model) is presented to discuss the effects of varying silicon chip length on the normal stress in solder joints. When the silicon chip length exceeds to 80 per cent of the total package length, the stress of the outermost solder joint increases rapidly. The design analysis findings have suggested that the failure of the outermost solder joint subjected to mechanical bending on the PCB assembly can be reduced by analyzing the analytical model.

This paper aims to introduce a knowledge‐based managemental prototype entitled E+ for environmental‐conscious construction relied on an integration of current environmental management tools in construction area. The overall objective of developing the E+ prototype is to facilitate selectively reusing the retrievable knowledge in construction engineering and management areas assembled from previous projects for the best practice in environmental‐conscious construction. The methodologies adopted in previous and ongoing research related to the development of the E+ belong to the operations research area and the information technology area, including literature review, questionnaire survey and interview, statistical analysis, system analysis and development, experimental research and simulation, and so on. The content presented in this paper includes an advanced E+ prototype, a comprehensive review of environmental management tools integrated to the E+ prototype, and an experimental case study of the implementation of the E+ prototype. It is expected that the adoption and implementation of the E+ prototype can effectively facilitate contractors to improve their environmental performance in the lifecycle of projectbased construction and to reduce adverse environmental impacts due to the deployment of various engineering and management processes at each construction stage.

The purpose of this study is to examine the effects of managers’ authentic leadership, person–job match in the six areas of worklife (AWLs) and emotional exhaustion on long-term care registered nurses’ job satisfaction.

A secondary analysis of baseline data from a national survey of 1,410 Canadian registered nurses from various work settings was used in this study, which yielded a subsample of 78 nurses working in direct care roles in long-term care settings. Hayes’ PROCESS macro for mediation analysis in SPSS was used to test the hypothesized model.

Findings showed that authentic leadership significantly predicted job satisfaction directly and indirectly through AWLs and emotional exhaustion.

Authentic leadership may provide guidance to long-term care managers about promoting nurses’ job satisfaction, which is essential to recruiting and retaining nurses to meet the care needs of an aging population.

As demand for care of the aged is increasing and creating challenges to ensuring a sufficient and sustainable nursing workforce, it is important to understand factors that promote long-term care nurses’ job satisfaction. Findings contribute to knowledge of long-term care nurses by suggesting that managers’ authentic leadership can positively affect nurses’ job satisfaction directly and indirectly through positive perceptions of AWLs and lower emotional exhaustion.

With increasing employment of ethnic minority (EM) workers from different nationalities to mitigate the growing demand for a construction workforce, the safety and health problems of these workers have become a significant concern. The purpose of this paper is to identify and rank according to severity the safety and health-related problems confronted by EM construction workers.

Grounded theory approach was employed to construct the main categories and subcategories of the construction safety and health problems of EM workers. A two-round Delphi survey of 18 experts, who are highly experienced in managing EM workers, was conducted to rank the relative severity of the identified safety and health problems.

A total of 14 subcategories and 4 categories of construction safety and health problems of EM workers were identified. Among the 14 subcategories, the most urgent and serious ones were insufficient safety materials and training in their native language, insufficient safety staff from EM origin, and safety communication barriers. In addition, safety and health problems at the corporate and governmental levels are also worth paying attention.

This study contributes to the update on the existing body of knowledge on safety and health problems encountered by EM construction workers and revelation of their peculiar situation in Hong Kong. Findings of the study will be of value to various stakeholders in formulating safety and health measures for EM construction workers.

Today’s growing numbers of contractor selection methodologies reflect the increasing awareness of the construction industry for improving its procurement process and performance. This paper investigates contractor classification methods that link clients’ selection aspirations and contractor performance. Multivariate techniques were used to study the intrinsic link between clients’ selection preferences, i.e. project‐specific criteria (PSC) and their respective levels of importance assigned (LIA), during tender evaluation for modelling contractor classification models in a data set of 68 case studies of UK construction projects. The logistic regression (LR) and multivariate discriminant analysis (MDA) were used. Results revealed that both techniques produced a good prediction on contractor performance and indicated that suitability of the equipment, past performance in cost and time on similar projects, contractor relationship with local authority, and contractor reputation/image are the most predominant PSC in the LR and MDA models among the 34 PSC. Suggests contractor classification models using multivariate techniques could be developed further.

Construction projects in Nigeria are generally characterized by cost and time overrun, substandard work, disputes and abandonment; emanating from several factors of which the wrong choice of contractors is a key factor. This study evaluated the criteria adopted by clients and consultants in contractors’ selection in Nigeria. Data were collected with the aid of questionnaire administered on clients and consultants within the Nigerian construction industry. Also prequalification/bid evaluation scores for eighty contractors were collected based on the criteria used in assessing them. The data collected were analysed with the aid of mean score and regression analysis. The result showed that past performance; contractors’ experience; workmanship quality; tender sum; and plant and equipment were the most important criteria for contractors’ prequalification/bid evaluation in Nigeria. A contractors’ selection model was eventually derived based on some of the identified factors. The goodness of fit of the model as defined by the value of r2 was found to be 99%. This therefore implies that only 1% is explained by other independent variables not included in the regression equation; hence the suitability of the model for contractors’ selection in Nigeria.

Nowadays, automotive engines are controlled by electronic control units (ECUs), and the engine idle speed performance is significantly affected by the setup of control parameters in the ECU. The engine ECU tune‐up is done empirically through tests on a dynamometer (dyno). In this way, a lot of time, fuel and human resources are consumed, while the optimal control parameters may not be obtained. The purpose of this paper is to propose a novel ECU setup optimization approach for engine idle speed control.

In the first phase of the approach, Latin hypercube sampling (LHS) and a multi‐input/output least squares support vector machine (LS‐SVM) is proposed to build up an engine idle speed model based on dyno test data, and then a genetic algorithm (GA) is applied to obtain optimal ECU setting automatically subject to various user‐defined constraints.

The study shows that the predicted results using the estimated model from LS‐SVM are in good agreement with the actual test results. Moreover, the optimization results show a significant improvement on idle speed performance in a test engine.

As the methodology is generic it can be applied to different vehicle control optimization problems.

The research is the first attempt to integrate a couple of paradigms (LHS, multi‐input/output LS‐SVM and GA) into a general framework for constrained multivariable optimization problems under insufficient system information. The proposed multi‐input/output LS‐SVM for modelling of multi‐input/output systems is original, because the traditional LS‐SVM modelling approach is suitable for multi‐input, but single output systems. Finally, this is the first use of the novel integrated framework for automotive engine idle‐speed control optimization.

This paper presents the concerns in manufacturing supply chain. Further this study investigates the role of information technology (IT) and information sharing (IS) in manufacturing supply chain and determines its impact towards supply chain integration (SCI), supply chain performance (SCP), and manufacturing firm performance (FP) in Malaysia. The theoretical framework was proposed for the study on the basis of existing literature. The study administered a survey questionnaire to collect data from manufacturing firms in Malaysia with 112 respondents. A multiple regression analysis is conducted to establish the relationship between IT, IS, SCI, and FP. The study finds that IT and sharing has significant positive effect towards and performance. Firms that use IT and practice IS across partners in the supply chain are more likely to integrate their internal and external value chain for better performance both within and across the manufacturing firms in the supply chain. This study can be of interest to the manufacturing industry as well as other industry practitioners interested in improving the performance of the organization and supply chain in total. For supply chain practitioners, this results indicate that the firms should adopt IT and IS practices to strategically improve SCI. This in turn will also improve the supply chain network and firm’s performance. This study employs a newly developed framework which depicts the causal relationship between IT, IS, SCI, Supply Chain Performance, and FP in Malaysia. Furthermore, it closes a gap in existing literature by examining the effect IT and communication (ICT) practices toward manufacturing firms’ performance and SCP in a single setting. In addition, the current study attempted to construct a model which would estimate and interpret SCP and FP simultaneously, and to evaluate this model in an empirical fashion.

This study aims to review the recent advancements in high entropy alloys (HEAs) called high entropy materials, including high entropy superalloys which are current potential alternatives to nickel superalloys for gas turbine applications. Understandings of the laser surface modification techniques of the HEA are discussed whilst future recommendations and remedies to manufacturing challenges via laser are outlined.

Materials used for high-pressure gas turbine engine applications must be able to withstand severe environmentally induced degradation, mechanical, thermal loads and general extreme conditions caused by hot corrosive gases, high-temperature oxidation and stress. Over the years, Nickel-based superalloys with elevated temperature rupture and creep resistance, excellent lifetime expectancy and solution strengthening L12 and γ´ precipitate used for turbine engine applications. However, the superalloy’s density, low creep strength, poor thermal conductivity, difficulty in machining and low fatigue resistance demands the innovation of new advanced materials.

HEAs is one of the most frequently investigated advanced materials, attributed to their configurational complexity and properties reported to exceed conventional materials. Thus, owing to their characteristic feature of the high entropy effect, several other materials have emerged to become potential solutions for several functional and structural applications in the aerospace industry. In a previous study, research contributions show that defects are associated with conventional manufacturing processes of HEAs; therefore, this study investigates new advances in the laser-based manufacturing and surface modification techniques of HEA.

The AlxCoCrCuFeNi HEA system, particularly the Al0.5CoCrCuFeNi HEA has been extensively studied, attributed to its mechanical and physical properties exceeding that of pure metals for aerospace turbine engine applications and the advances in the fabrication and surface modification processes of the alloy was outlined to show the latest developments focusing only on laser-based manufacturing processing due to its many advantages.

It is evident that high entropy materials are a potential innovative alternative to conventional superalloys for turbine engine applications via laser additive manufacturing.