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The mechanical integrity of solder joint interconnects in PWB assemblies with micro ‐ BGA, chip scale, and LGA packages are being questioned as the size and pitch decrease. Three‐point cyclic bend testing provides a useful tool for characterizing the expected mechanical cycling fatigue reliability of PWB assemblies. Cyclic bend testing is useful for characterizing bending issues in electronic assemblies such as repetitive keypad actuation in cell phone products. This paper presents the results of three‐point bend testing of PWB assemblies with fine pitch packages. The methodology of materials analyses of the metallurgy of solder interconnects following mechanical bending and thermal cycle testing is described.

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 chapter reviews the existing empirical evidence on how social insurance affects health. Social insurance encompasses programs primarily designed to insure against health risks, such as health insurance, sick leave insurance, accident insurance, long-term care insurance, and disability insurance as well as other programs, such as unemployment insurance, pension insurance, and country-specific social insurance programs. These insurance systems exist in almost all developed countries around the world. This chapter discusses the state-of-the art evidence on each of these social insurance systems, briefly reviews the empirical methods for identifying causal effects, and examines possible limitations to these methods. The findings reveal robust and rich evidence on first-stage behavioral responses (“moral hazard”) to changes in insurance coverage. Surprisingly, evidence on how changes in coverage impact beneficiaries’ health is scant and inconclusive. This lack of identified causal health effects is directly related to limitations on how human health is typically measured, limitations on the empirical approaches, and a paucity of administrative panel data spanning long-time horizons. Future research must be conducted to fill these gaps. Of particular importance is evidence on how these social insurance systems interact and affect human health over the life cycle.

This book aimed to conceptualise a construction workforce management model suitable for effectively managing workers in construction organisations. To this end, this chapter presents the conceptualised model, which consists of seven workforce management practices with their respective measurement variables. Drawing from existing theories, models, and practices, the chapter concludes that a construction organisation that will attain its strategic objectives in the current fourth industrial revolution era must be willing to promote effective recruitment and selection, compensation and benefits, performance management and appraisal, employee involvement and empowerment, training and development, as well as improving workers emotional intelligence and handling external environment pressure. These practices can promote proactiveness, participation, and improved skills and can lead to effective commitment, better quality, and flexibility within the organisation.

The lead‐free solder joint reliability of several printed circuit board mounted high‐density packages, when subjected to temperature cycling was investigated by finite element modelling. The packages were a 256‐pin plastic ball grid array (PBGA), a 388‐pin PBGA, and a 1657‐pin ceramic column grid array. Emphasis was placed on the determination of the creep responses (e.g. stress, strain, and strain energy density) of the lead‐free solder joints of these packages.

Failure analyses of the lead‐free and SnPb solder joints of high‐density packages such as the plastic ball grid array and the ceramic column grid array soldered on SnCu hot‐air solder levelling electroless nickel‐immersion gold or NiAu, and organic solderability preservative Entek printed circuit boards are presented. Emphasis is placed on determining the failure locations, failure modes, and intermetallic compound composition for these high‐density packages' solder joints after they have been through 7,500 cycles of temperature cycling. The present results will be compared with those obtained from temperature cycling and finite element analysis.

The purpose of this paper is to answer the call for CSR communication research to develop and substantiate outcomes that may better explain CSR communication strategies and practices. The paper takes the research a step further, exploring the role of legitimacy in CSR communication research.

A literature collection methodology, combined with directed content analysis, was used to identify central themes in the literature.

The following categories of studies were identified: perception, impact and promotion studies; image and reputation studies; performance studies; and conceptual/rhetorical studies. Addressed from a legitimacy perspective, the study found that the most important types of legitimizing communicative practices articulated in the four types of studies were related to: seeking knowledge about stakeholders through perception, impact and promotion activities; monitoring and controlling the environment through image and reputation activities; creating stakeholder value through collaboration and engagement; and persuading and convincing stakeholders through rhetorics, CSR models and concepts. The study also found that practices and activities related to perceiving stakeholders’ expectations, needs and requirements are assumed to be most effective for corporations aiming at building or maintaining legitimacy.

The key contribution of the paper lies in exploring how corporate legitimacy is anticipated and extrapolated in the CSR communication literature, including which pinpointed CSR communication strategies and practices are assumed to be more effective than others in bridging stakeholders’ perceptions of corporations’ social and environmental actions. Until date, no reviews exist of the role of legitimacy in CSR communication research.

The purpose of this paper is to quantify the labor market outcomes of people with disabilities (PwD) in Indonesia and compares them to people without disabilities. It first studies the labor force participation of PwD before examining the large and persistent wage gaps they face. It explores whether these wage gaps are explained by differences in productivity, a distinction which has important implications for policies addressing these gaps.

The analysis is based on the Indonesian Family Life Survey Wave 5, which includes unique questions allowing for several definitions of disability. Multinomial logistic regression is used to study differences in type of employment for PwD. Wage gaps are estimated and corrected for selection using propensity score matching, supported by a Heckman selection model and Oaxaca–Blinder decomposition. Comparisons with other physically disadvantaged subgroups and the analysis of heterogeneity by job requirements and sector of work explore whether productivity gaps help explain wage gaps.

PwD generally have lower unconditional labor force participation, but disparities largely disappear when controlling for characteristics. Moreover, patterns vary depending on whether the measure of disability used depends on prior medical diagnosis. PwD that do not require prior diagnosis tend to work in more vulnerable employment. When they are employed for wages, people with these types of disabilities face lower wages, up to 22% lower. Meanwhile, (surprisingly) those with medically diagnosed conditions face no difference or a wage premium. This paper finds compelling evidence that, where a wage penalty exists, a substantial part is unexplained by observable characteristics.

Previous literature on disability has been mostly based on studies of high-income economies. This paper extends the literature to Indonesia, which differs from high-income contexts due to lack of mental healthcare resources and assistive technologies, as well as weaker rule of law. It provides unique insights based on types of disability and the salient dimensions of disability in the workplace. It also provides evidence that productivity differences do not explain the wage gap.

The purpose of this paper is to address the challenge for knowledge exchange between disciplines that study past urban landscapes, such as archaeologists, historians and historical geographers and disciplines that work on new urban landscapes such as architects and spatial planners. It presents the design, deployment and evaluation of a heritage instrument, the “digital cultural biography” (DCB), which aims to allow future-oriented disciplines to make more historical and heritage informed decisions.

The paper makes three contributions. First it presents a methodology to disseminate geographic information across disciplines by applying the biography of the landscape research strategy. Second it translates this methodology to a digital instrument, the DCB, which makes it possible to configure the historical and heritage features diachronically as well as spatially. And third it evaluates the added value of this instrument by organizing a design concourse and applying various evaluation methods. The Roman neighbourhood of Testaccio functions as the use case for this study.

The research shows a high potential to use digital tooling based on geospatial technologies to support the dialogue between future and past-oriented disciplines.

The paper discusses how the recently developed biography of the landscape method can be used as a tool for collaboration between heritage managers and spatial planners. Moreover, for the first time it applies and evaluates digital tools and geospatial technologies to support this approach.