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This paper aims to present the novel stacked machine learning approach (SMLA) to estimate low-cycle fatigue (LCF) life of SAC305 solder across structural parts. Using the finite element simulation (FEM) and continuous damage mechanics (CDM) model, a fatigue life database is built. The stacked machine learning (ML) model's iterative optimization during training enables precise fatigue predictions (2.41% root mean square error [RMSE], R² = 0.975) for diverse structural components. Outliers are found in regression analysis, indicating potential overestimation for thickness transition specimens with extended lifetimes and underestimation for open-hole specimens. Correlations between fatigue life, stress factors, nominal stress and temperature are unveiled, enriching comprehension of LCF, thus enhancing solder behavior predictions.

This paper introduces stacked ML as a novel approach for estimating LCF life of SAC305 solder in various structural parts. It builds a fatigue life database using FEM and CDM model. The stacked ML model iteratively optimizes its structure, yielding accurate fatigue predictions (2.41% RMSE, R² = 0.975). Outliers are observed: overestimation for thickness transition specimens and underestimation for open-hole ones. Correlations between fatigue life, stress factors, nominal stress and temperature enhance predictions, deepening understanding of solder behavior.

The findings of this paper highlight the successful application of the SMLA in accurately estimating the LCF life of SAC305 solder across diverse structural components. The stacked ML model, trained iteratively, demonstrates its effectiveness by producing precise fatigue lifetime predictions with a RMSE of 2.41% and an “R²” value of 0.975. The study also identifies distinct outlier behaviors associated with different structural parts: overestimations for thickness transition specimens with extended fatigue lifetimes and underestimations for open-hole specimens. The research further establishes correlations between fatigue life, stress concentration factors, nominal stress and temperature, enriching the understanding of solder behavior prediction.

The authors confirm the originality of this paper.

Temperature is an important load for a ballastless track. However, little research has been conducted on the dynamic responses when a train travels on a ballastless track under the temperature gradient. The dynamic responses under different temperature gradients of the slab are theoretically investigated in this work.

Considering the moving train, the temperature gradient of the slab, and the gravity of the slab track, a dynamic model for a high-speed train that runs along the CRTS III slab track on subgrade is developed by a nonlinear coupled way in Abaqus.

The results are as follows: (1) The upward transmission of the periodic deformation of the slab causes periodic track irregularity. (2) Because of the geometric constraint of limiting structures, the maximum bending stresses of the slab occur near the end of the slab under positive temperature gradients, but in the middle of the slab under negative temperature gradients. (3) The periodic deformation of the slab can induce periodic changes in the interlayer stiffness and contact status, leading to a large vibration of the slab. Because of the vibration-reduction capacity of the fastener and the larger mass of the concrete base, the accelerations of both the slab and concrete base are far less than the acceleration of the rail.

This study reveals the influence mechanism of temperature gradient-induced periodic deformation in the dynamic responses of the train-track system, and it also provides a guide for the safe service of CRTS III slab track.

This paper aims to contribute novel insights into the analysis of thin functionally graded material (FGM) plates with variable thickness, considering both temperature-dependent and independent material properties, focusing on critical linear buckling temperature rise and the effect of critical linear moisture for various moisture concentrations.

The study derives stability and equilibrium equations for thin rectangular FGM plates under hygrothermal loading, employing classical plate theory (CPT). Buckling behavior is examined using Galerkin’s method to obtain pre-buckling force resultants.

The findings highlight significant increases in critical buckling temperature with aspect ratio, distinct temperature sensitivity between materials and increasing moisture susceptibility with larger aspect ratios. These insights inform material selection and design optimization for FGM plates under hygrothermal loading, enhancing engineering applications.

This research primarily focuses on hypothetical scenarios and mathematical model development and analysis.

This paper presents original contributions in the field by addressing the hygrothermal buckling analysis of thin FGM rectangular plates with variable thickness, utilizing CPT, thereby enriching the understanding of structural behavior in varying environmental conditions.

This chapter takes an overview look at open digital infrastructures for financial services: what they are, why they are important for digital financial landscape, and thus why the central banks might need to take an active role to promote them. This chapter also reviews some concrete examples of open digital infrastructures in various jurisdictions to give some context.

Considering the inherent relationship between environmental degradation and the process of economic development, the latter is particularly reliant on the accumulation of human capital, which also emerges as one of the fundamental principles underlying green growth. However, this relationship tends to overlook varying levels of human capital. Hence, the purpose of this study is to examine the enduring associations between the stock of high human capital and green economies in terms of environmental sustainability among the key countries in the Asia Pacific region, namely Australia, Japan, Singapore, and South Korea, spanning the period from 1990 to 2022.

This paper employs second-generation techniques. The long-term relationships were estimated using two constantly updated models - fully modified and bias corrected, CUP-FM and CUP-BC, respectively, to guarantee the robustness of our conclusions for the presence of cross-sectional dependency.

There is a long-term relationship between the stock of high human capital and the sustainability of the environment, in the same way that we have also found the same relationship between the development of socioeconomic practices of green economies. Finally, we conclude that, in the same way as the environmental Kuznets curve, the countries in our sample incur less environmental pollution as their level of income increases. This relationship may be motivated by a process of technological substitution and investment in the development of new techniques and technology to improve the efficiency of productivity with respect to the environment.

We suggest that investing in education and promoting green economies can be powerful tools in the fight against climate change and promoting environmental sustainability. By prioritizing investments in renewable energy and sustainable technologies, policymakers can promote long-term economic and environmental health. Moreover, the findings suggest that promoting education in countries with high levels of environmental pollution can develop the knowledge and skills needed to implement sustainable practices and technologies. Ultimately, these efforts can contribute to improving income, productivity, and society's living conditions while reducing the environmental impact.

This research studies for the first time the load capacity curve hypothesis in determining the effects of the stock of high human capital and green economies on the environment. Consequently, limited papers have used the load capacity factor in the study of the relationships that we propose, especially that of human capital, which has scarcely been studied in relation to its contribution to the environmental fight.

Ageing is a global concern that poses many challenges for governments, particularly in relation to the pressing issue of how to provide adequate social protection for the increasing number of elderly. Alongside rapid social and demographic transformation, Indonesia is especially challenged by the increasing number of elderly in need of formal care that is stretching the capacities of government and necessitates improvements in the social protection system. This study examines governance capacity in nursing homes and offers recommendations for improving the social protection system.

The research presents a qualitative case study of government aged care centres in East Java and the experiences of residents and staff of three centres managed by the Provincial Social Service of East Java. The case study is based on ethnographic fieldwork, semi-structured interviews with 32 informants comprising directors, managers, staff and elderly residents of nursing homes.

The research finds that while social protection is in place, governance capacities at the provincial and local level are thinly stretched. The research highlights the tensions between existent governance capacities – in terms of mobility, decision-making, implementation and established local structures of governance and management – and the inability to meet the increasing demands for government elder care services and resources amidst broader societal transformations such as shifts in cultural framing of familial care of elderly. The findings point to the importance of understanding the dynamic relationship between governance capacity and the shifting terrains of elderly care due to societal transformation.

The research brings attention to the pivotal role that governance capacity plays in shaping the experiences and challenges of local government level elder care provision and the growing need for elder care in the face of an ageing population and shifts in kinship and family elder care arrangements. Elder care is not simply about addressing basic needs but also the quality and dignity of elderly and this is not easy to address where social protection systems are stretched beyond capacity. Recommendations are provided for enhancing government policy and expanding the scope for building cross-sectorial partnerships.

Work overload has become a relevant issue in the Information Technology (IT) industry, with negative effects for individuals and organizations alike. This study aims to analyse the role of personal resources in a broad model regarding the effects of work overload on performance and well-being for the particular case of IT professionals. Considering the specificities of the IT industry, three personal resources were included in this study: one stable personality variable (conscientiousness) and two more malleable variables (work-life balance and psychological detachment).

To test the model, the authors use a sample of 144 IT Portuguese professionals. The authors collected data through an online questionnaire shared in social networks and IT social network communities. The authors use partial least squares (PLS) for data analysis.

The results show that work overload negatively impacts on employees’ life satisfaction, psychological detachment, work-life balance and task performance. Conscientiousness is positively related with two positive outcomes: task performance and life satisfaction. Work-life balance has a mediating effect in the relationship between work overload and life satisfaction.

These findings emphasize the need to promote conscientiousness in IT professionals, as well as reduce workload and promote family-friendly working environments to foster work-life balance and life satisfaction.

By testing this model, the authors aim to contribute to the current knowledge on the role of personal resources in the Job Demands-Resources model, which is still unclear and under-researched.

This study aims to build on the well-documented case of the Olympus scandal to dissect how social networks and corporate culture enabled corporate elites to commit fraud across multiple generations of leaders.

A flexible pattern matching approach was used to identify matches and mismatches between behavioural theory in corporate governance and the patterns observed in data from diverse sources.

The study applies the behavioural theory of corporate governance from different perspectives. Social networks and relationships were essential for the execution of the fraud and keeping it secret. The group of corporate elites actively created opportunities for committing misappropriation. This research presents individuals committing embezzlement because the opportunity already exists, and they can enrich themselves. The group of insiders who committed the fraud elaborated the rationalizations to others and asked outside associates to help rationalise the activities, while usually individuals provide rationalizations to themselves only.

The social processes among actors described in this case can inform the design of mechanisms to detect these behaviours in similar contexts.

This study provides both perspectives on the fraud scandal: the one of the whistle-blowers, and the opposing side of the transgressors and their associates. The extant case studies on Olympus presented the timeframe of the scandal right after the exposure. The current study dissects the events during the fraud execution and presents the case in a neutral or a negative light.

The team collective voice (TCV) concept has received limited attention in existing research despite its potential significance, particularly within Eastern cultural contexts. Hence, this paper aims to extend the employee voice literature by conducting a comprehensive exploration of the role of TCV as opposed to individual voice (IV) in promoting team innovative performance (TIP).

The theoretical model is tested with survey data collected among ICT employees who work in large telecommunication organizations in Vietnam.

TCV was used more by participants than IV. Both IV and TCV exhibited noteworthy influences on TIP explained by the role of routine changes, with TCV serving as a full mediator for the relationship between IV and TIP. In addition, team autonomy (TA) also significantly enhanced TIP.

By measuring TCV as shared and consensus team voice, this study makes significant contributions to employee voice literature. It not only confirms the prevalence but also offers insightful explanations for why Vietnamese employees tend to favor TCV over IV. Additionally, the findings enrich the innovation literature by presenting a novel perspective on how employee voice can enhance TIP through the introduction of exogenous routine changes. It introduces a unique perspective on employee voice as a form of a search routine, distinct from Nelson and Winter's (1982) conceptualization of search, generating changes in lower-order routines, ultimately contributing to enhanced team innovation and performance.

In 2022, the International Network for Quality Assurance (QA) Agencies in Higher Education (INQAAHE) published the new guidelines by adding three QA modules in response to the changing higher education landscape. The paper aims to investigate the transformative focus of quality assurance in higher education globally as well as Asian response to three new QA modules according to the INQAAHE ISGs.

The research conducted a quantitative approach for data collection. An on-line survey was conducted to perceive QA practices, perceptions toward new emerging QA modules and challenges encountered. In total, there were 26 responses from 18 territories with 22 QA agencies. A total of 13 out of them have a national qualifications framework in place.

Three are three major findings in the study. First, national policy and criteria and standards in distance education have been developed in the majority of Asian nations. Second, non-signatories of the Tokyo Convention had a higher proportion of having related policies, regulations and criteria in CBHE and distance education. Third, national policies and regulations; and lack of professional staff are two common challenges implementing QA in new types of providers.

The findings are of value for policymakers, QA agencies and universities to advocate the new QA model as a systematic approach in response to changing higher education landscape in the post pandemic era.