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This study aims to investigate the thermal fracture mechanism of moisture-preconditioned SAC305 ball grid array (BGA) solder joints subjected to multiple reflow and thermal cycling.

The BGA package samples are subjected to JEDEC Level 1 accelerated moisture treatment (85 °C/85%RH/168 h) with five times reflow at 270 °C. This is followed by multiple thermal cycling from 0 °C to 100 °C for 40 min per cycle, per IPC-7351B standards. For fracture investigation, the cross-sections of the samples are examined and analysed using the dye-and-pry technique and backscattered scanning electron microscopy. The packages' microstructures are characterized using an energy-dispersive X-ray spectroscopy approach. Also, the package assembly is investigated using the Darveaux numerical simulation method.

The study found that critical strain density is exhibited at the component pad/solder interface of the solder joint located at the most distant point from the axes of symmetry of the package assembly. The fracture mechanism is a crack fracture formed at the solder's exterior edges and grows across the joint's transverse section. It was established that Au content in the formed intermetallic compound greatly impacts fracture growth in the solder joint interface, with a composition above 5 Wt.% Au regarded as an unsafe level for reliability. The elongation of the crack is aided by the brittle nature of the Au-Sn interface through which the crack propagates. It is inferred that refining the solder matrix elemental compound can strengthen and improve the reliability of solder joints.

Inspection lead time and additional manufacturing expenses spent on investigating reliability issues in BGA solder joints can be reduced using the study's findings on understanding the solder joint fracture mechanism.

Limited studies exist on the thermal fracture mechanism of moisture-preconditioned BGA solder joints exposed to both multiple reflow and thermal cycling. This study applied both numerical and experimental techniques to examine the reliability issue.

This chapter of the book seeks to use famous mathematical functions (statistical distribution functions) in evaluating and analyzing supply chain network data related to supply chain management (SCM) elements in organizations. In other words, the main purpose of this chapter is to find the best-fitted statistical distribution functions for SCM data. Explaining how to best fit the statistical distribution function along with the explanation of all possible aspects of a function for selected components of SCM from this chapter will make a significant attraction for production and services experts who will lead their organization to the path of competitive excellence. The main core of the chapter is the reliability values related to the reliability function calculated by the relevant chart and extracting other information based on other aspects of statistical distribution functions such as probability density, cumulative distribution, and failure function. This chapter of the book will turn readers into professional users of statistical distribution functions in mathematics for analyzing supply chain element data.

The present study aims to investigate the psychometric properties of the picture story exercise (PSE), a tool for measuring implicit motivations in Iran.

The research method is descriptive correlation and was conducted in two studies. In the first study 24 psychology master’s students were selected by convenience sampling method and tested them to check retest and inter-coder reliability. The second study investigated the correlation between self-reports and the PSE test on a sample of managers. Its statistical population comprised all the managers of a refinery company, 50 people were selected by convenience sampling method. To check the concurrent validity of the PSE test, the participants of the second study, completing the PSE, also completed the needs questionnaire of Steers and Porter (1979).

The findings showed that the PSE test in the Iranian sample had high retest reliability (0.62 on mean) and inter-coder reliability (0.87 on mean), and, following previous research, it does not show a significant relationship with self-reported motives.

PSE can be used in future research as a tool that has demonstrated its reliability and validity in the Iranian sample.

Measurement of implicit motives is a practical factor for predicting people’s behavior, the necessity of using tools that can accurately evaluate implicit motives is strongly felt. Taking into account the fact that so far, in Iranian samples, implicit motivations have not been measured, therefore, the current research is trying to answer this question, whether one of the most important and prominent tools that were made for this purpose and used in various studies can also be used in Iranian samples.

Although the fitness switching costs scale (FSCS) was shown to have sound psychometric properties, the length of the 54-item may impose burdens on survey participants and present methodological and analytic challenges for researchers and practitioners. Therefore, the present study shortened and validated two versions of the FSCS, namely the 33-item FSCS (FSCS-33) and the 11-item FSCS (FSCS-11).

In Study 1 (n = 411), the most useful items from the FSCS for the FSCS-33 and FSCS-11 were identified using item response theory (IRT). Study 2 (n = 391) and Study 3 (n = 400) assessed the psychometric properties of the FSCS-33 and FSCS-11, respectively, using partial least squares structural equation modeling.

The FSCS-33 and FSCS-11 demonstrated strong reliability and validity in assessing switching costs in fitness centers.

The psychometrically sound short-form scales provide researchers and practitioners with convenient and accurate means of measuring switching costs in fitness centers.

This research sought to examine the differential effect of chatbot banking artificial intelligence (AI) on consumer experience in the banking industry. A positivist paradigm was adopted to sample 389 consumers who were previously exposed to chatbot banking in Zimbabwe. A causal research design was employed whilst a quantitative approach was followed. In analysing data, the research study applied the structural equation modelling (SEM) technique. The authors found that chatbot banking significantly improves customer experience (CX) in the banking industry. Reliability and responsiveness of the chatbot need to be enhanced for effective improvements in CX. A need was also identified to enhance CX through the development of an ease-to-use chatbot which is embedded in everyday messaging applications of consumers. A significant association was also found between perceived benefits of chatbot banking and CX. This study informs the development of competitive advantage by banks and other related companies through AI-based CX management strategies. In times of pandemics and beyond, chatbot banking can be very instrumental in improving CX.

The primary intent of this study was to assess the influence of novelty-seeking on the satisfaction of consumers. The investigation concentrated on Malaysian consumers who have experience using online food delivery (OFD) applications.

To perform the research, non-probability and convenience sampling methods were enforced to gather the required data. An online questionnaire in the form of a Google Survey was conducted in Kuala Lumpur, Malaysia. Upon completion of the survey, the results were analyzed using SPSS software. Both the Service Quality (SERVQUAL) model and expectation disconfirmation theory (EDT) were exploited to shed light on the impact of consumer satisfaction.

Analysis of responses from the 250 participants unveiled that novelty-seeking positively influences consumer satisfaction. The finding depicted that reliability and responsiveness have the most positive impact on consumer satisfaction whereas tangibility has no effect on the satisfaction of consumers by using OFD applications.

This study had three main limitations: first, the limitations on access to the participants during the pandemic; second, combining quantitative and qualitative methods to obtain more accurate results; third, the study was limited to the context of Kuala Lumpur, Malaysia.

The conclusions brought to the fore that OFD marketers should provide appropriate service quality while concentrating on novelty and well-designed apps to surge consumer satisfaction.

OFD apps have facilitated customers' access to various meals and helped food vendors survive in the competitive marketplace. A new aspect, novelty-seeking, is added to the SERVQUAL dimensions (i.e. empathy, tangibility, reliability, assurance and responsiveness) identified in the literature review.

This study aims to investigate the possible defects and their root causes in a soft-termination multilayered ceramic capacitor (MLCC) when subjected to a thermal reflow process.

Specimens of the capacitor assembly were subjected to JEDEC level 1 preconditioning (85 °C/85%RH/168 h) with 5× reflow at 270°C peak temperature. Then, they were inspected using a 2 µm scanning electron microscope to investigate the evidence of defects. The reliability test was also numerically simulated and analyzed using the extended finite element method implemented in ABAQUS.

Excellent agreements were observed between the SEM inspections and the simulation results. The findings showed evidence of discontinuities along the Cu and the Cu-epoxy layers and interfacial delamination crack at the Cu/Cu-epoxy interface. The possible root causes are thermal mismatch between the Cu and Cu-epoxy layers, moisture contamination and weak Cu/Cu-epoxy interface. The maximum crack length observed in the experimentally reflowed capacitor was measured as 75 µm, a 2.59% difference compared to the numerical prediction of 77.2 µm.

This work's contribution is expected to reduce the additional manufacturing cost and lead time in investigating reliability issues in MLCCs.

Despite the significant number of works on the reliability assessment of surface mount capacitors, work on crack growth in soft-termination MLCC is limited. Also, the combined experimental and numerical investigation of reflow-induced reliability issues in soft-termination MLCC is limited. These cited gaps are the novelties of this study.

The increasing adverse impact of human behavior toward the environment has brought in changes in research focus on environmental behavior toward the workplace. Because the employee spends one-third of his day in his workplace, the initiatives taken by the employee also have an impact on the company’s environmental stance. Therefore, the researchers gradually focus on employee green behavior (EGB) and its measurement. The study aims to devise a tool for measuring EGB.

Two studies were carried out using the survey method using the purposive sampling technique. The data were collected (Studies 1 and 2) from managers and supervisors working in manufacturing companies located in Kolkata, India.

The first study was done to extract the principal factors using an initial 30 items (N = 220). The result of the principal component analysis shows the emergence of three factors spread over 20 items with loadings above 0.40. The 20-item scale was again administered on managers and supervisors (N = 243). The second study was carried out to examine the convergent and discriminant validity as well as stability of the tool through confirmatory factor analysis (CFA) (N = 243). The result of CFA showed the presence of 16 items spread through three factors: practice and policy, digital use and recycle and reuse. Multiple fit indices support a three-factor model of the 16-item EGB scale.

The scale would be a good measure of EGB and can be used for further research. The EGB scale is a composite scale containing three major dimensions that can be used as a complete measure of EGB.

The present research aims to fill the current gap by building a comprehensive tool for measuring EGB. The present scale has also addressed the shortcoming of the previous scale and tried to include varied proenvironmental behaviors exhibited in the workplace.

The purpose of this study is to propose a simplifying approach for modelling a reliability test. Modelling the reliability tests of printed circuit board (PCB)/microelectronic component assemblies requires the adoption of several simplifying assumptions. This study introduces and validates simplified assumptions for modeling a four-point bend test on a PCB/wafer-level chip scale packaging assembly.

In this study, simplifying assumptions were used. These involved substituting dynamic imposed displacement loading with an equivalent static loading, replacing the spherical shape of the interconnections with simplified shapes (cylindrical and cubic) and transitioning from a three-dimensional modelling approach to an equivalent two-dimensional model. The validity of these simplifications was confirmed through both quantitative and qualitative comparisons of the numerical results obtained. The maximum principal plastic strain in the solder balls and copper pads served as the criteria for comparison.

The simplified hypotheses were validated through quantitative and qualitative comparisons of the results from various models. Consequently, it was determined that the replacement of dynamic loading with equivalent static loading had no significant impact on the results. Similarly, substituting the spherical shape of interconnections with an equivalent shape and transitioning from a three-dimensional approach to a two-dimensional one did not substantially affect the precision of the obtained results.

This study serves as a valuable resource for researchers seeking to model accelerated reliability tests, particularly in the context of four-point bending tests. The results obtained in this study will assist other researchers in streamlining their numerical models, thereby reducing calculation costs through the utilization of the simplified hypotheses introduced and validated herein.

This study aims to adapt and validate the Job Crafting Scale (JCS), a measure based on the conceptualization of job crafting of the job demands–resources theory, for a sample of Portuguese workers and to test its psychometric properties regarding validity (factor, convergent, discriminant, and criterion) and reliability.

Two subsamples (n1 = 315 and n2 = 329) of Portuguese workers aged 18 years old and over participated in this research. Exploratory factor analysis and confirmatory factor analysis were used to assess the factor structure.

The results indicated that the Portuguese version of the JCS, with 18 items, has a factor structure composed of four-correlated factors. Furthermore, the results demonstrated the existence of factor, discriminant, and criterion validity, as well as reliability.

This study provides a job crafting measure adapted to the Portuguese language that can serve as a diagnostic tool for workers and organizations.

Este estudio tuvo como objetivo adaptar y validar la Job Crafting Scale (JCS), una medida basada en la conceptualización de job crafting de la Teoría de Demandas-Recursos, para una muestra de trabajadores portugueses y probar sus propiedades psicométricas en cuanto a validez (factor, convergente, discriminante y de criterio) y confiabilidad.

En esta investigación participaron dos submuestras (n1 = 315 y n2 = 329) de trabajadores portugueses de 18 años o más. Se utilizó un análisis factorial exploratorio y un análisis factorial confirmatorio para evaluar la estructura factorial.

Los resultados indicaron que la versión portuguesa del JCS, con 18 ítems, tiene una estructura factorial compuesta por cuatro factores correlacionados. Además, los resultados demostraron la existencia de validez factorial, discriminante y de criterio, así como confiabilidad.

Este estudio proporciona una medida de job crafting adaptada a la lengua portuguesa que puede servir como herramienta de diagnóstico para trabajadores y organizaciones.

Este estudo teve como objetivo adaptar e validar a Job Crafting Scale (JCS), uma medida baseada na conceptualização de job crafting da Teoria das Exigências-Recursos, numa amostra de trabalhadores portugueses e testar as suas propriedades psicométricas quanto à validade (fatorial, convergente, discriminante e de critério) e fiabilidade.

Duas subamostras (n1 = 315 e n2 = 329) compostas por trabalhadores portugueses com 18 ou mais anos foram recolhidas. Foram utilizadas uma análise fatorial exploratória e uma análise fatorial confirmatória para analisar a estrutura fatorial.

Os resultados obtidos indicaram que a versão portuguesa da JCS, composta por 18 itens, possui uma estrutura fatorial composta por quatro fatores correlacionados. Além disso, os resultados demonstraram a existência de validade fatorial, discriminante e de critério, bem como de fiabilidade.

Este estudo fornece uma medida de job crafting adaptada para a língua portuguesa que pode servir como ferramenta de diagnóstico para trabalhadores e organizações.