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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…
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 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…
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…
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.
Three decades of academic and professional discourse on HR technologies (HRTs) have produced continued disagreement over construct definitions and research streams that…
Three decades of academic and professional discourse on HR technologies (HRTs) have produced continued disagreement over construct definitions and research streams that are highly fragmented. These realities suggest that greater consistency in meanings is sorely needed if we are to integrate and upgrade knowledge in this area. This chapter draws on the findings of a systematic research review to properly define the content domains of human resource information systems (HRIS), virtual human resources (virtual HR), electronic human resource management (e-HRM), and business-to-employee (B2E) systems. An integrative synthesis was performed on 242 system-level writings that appeared in the literature from 1983 to 2017. The weight of the evidence strongly supports treating HRIS, virtual HR, e-HRM, and B2E systems as independent, complimentary constructs. While the first three comprise a firm’s HRT system, the fourth construct is more appropriately positioned in the business-collaborative system. The sample was further evaluated with an analytic framework to detect patterns of practice in research designs. This revealed that much more attention has been focused on system actions and outcomes than on attitudes and system characteristics. Different units of analysis were well represented aside from trans-organizational studies. Finally, a case is made for better contextualizing HRT research by recognizing differences in assimilation stage, functional penetration, and collective proficiency. These factors are rarely mentioned, let alone studied, raising additional concerns about measurement error. Detailed suggestions are offered on ways to incorporate them. Together, these materials should promote more sophisticated and generalizable assessments of technology, improving our ability to understand its impacts.
The purpose of the study was to explore in literature what different leadership styles and behaviors of head nurses have a positive influence on the outcomes of patient…
The purpose of the study was to explore in literature what different leadership styles and behaviors of head nurses have a positive influence on the outcomes of patient safety or quality of care.
We reviewed the literature from January 2000 until September 2011. We searched Pubmed, Embase, Cinahl, Psychlit, and Econlit.
We found 10 studies addressing the relationship between head nurse leadership and safety and quality. A wide array of styles and practices were associated with different patient outcomes. Transformational leadership was the most used concept in the studies. A trend can be observed over these studies suggesting that a trustful relationship between the head nurse and subordinates is an important driving force for the achievement of positive patient outcomes. Furthermore, the effects of these trustful relationships seem to be amplified by supporting mechanisms, often objective conditions like clinical pathways and, especially, staffing level.
This study offers an up-to-date review of the limited number of studies on the relationship between nurse leadership and patient outcomes. Although mostly transformational leadership was found to be responsible for positive associations with outcomes, also contingent reward had positive influence on outcomes. We formulated some comments on the predominance of the transformational leadership concept and suggested the application of complexity theory and political leadership for the current context of care. We formulated some implications for practice and further research, mainly the need for more systematic empirical and cross cultural studies and the urgent need for the development of a validated set of nurse-sensitive patient outcome indicators.