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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.

The lightweight design of aircraft seats can significantly improve fuel efficiency and reduce greenhouse gas emissions. Metal additive manufacturing (MAM) can produce lightweight topology-optimized designs with improved performance, but limited build volume restricts the printing of large components. The purpose of this paper is to design a lightweight aircraft seat leg structure using topology optimization (TO) and MAM with build volume restrictions, while satisfying structural airworthiness certification requirements.

TO was used to determine a lightweight conceptual design for the seat leg structure. The conceptual design was decomposed to meet the machine build volume, a detailed CAD assembly was designed and print orientation was selected for each component. Static and dynamic verification was performed, the design was updated to meet the structural requirements and a prototype was manufactured.

The final topology-optimized seat leg structure was decomposed into three parts, yielding a 57% reduction in the number of parts compared to a reference design. In addition, the design achieved an 8.5% mass reduction while satisfying structural requirements for airworthiness certification.

To the best of the authors’ knowledge, this study is the first paper to design an aircraft seat leg structure manufactured with MAM using a rigorous TO approach. The resultant design reduces mass and part count compared to a reference design and is verified with respect to real-world aircraft certification requirements.

This study aims to explore the evolution of corporate governance through a 100-year-old Italian Barilla pasta family business from its founding to 1971. The study builds on prior research which has applied the three-circle model of family business systems in a historic context.

Using legal records, five phases in the history of Barilla are noted. Annual reports and other sources have allowed for some more insights into business events and developments. Then, drawing on the three-circle model of family business, the corporate governance regime is mapped to the model and the family actors.

The findings here support extant literature in that the systems in the three-circle model are found to overlap more in a historic setting. Challenges with the three-circle model are also noted, specifically, when corporate governance is considered across a century of an organisation’s history.

This study supports prior use of three-circle model of a family business in an historic context, providing further evidence the model is not static over time. Contrary to the original three-circle model, this study suggests that family actors can potentially occupy more than one location in the model if the non-human actor of corporate governance and its effect on human actors is also considered.

The aim of this paper is to provide a narrative review of previous research on tourism demand modelling and forecasting and potential future developments.

A narrative approach is taken in this review of the current body of knowledge.

Significant methodological advancements in tourism demand modelling and forecasting over the past two decades are identified.

The distinct characteristics of the various methods applied in the field are summarised and a research agenda for future investigations is proposed.

本文旨在对先前关于旅游需求建模和预测的研究进行叙述性回顾并对未来潜在发展进行展望。

本文采用叙述性回顾方法对当前知识体系进行了评论。

本文确认了过去二十年旅游需求建模和预测方法论方面的重要进展。

本文总结了该领域应用的各种方法的独特特征, 并对未来研究提出了建议。

El objetivo de este documento es ofrecer una revisión narrativa de la investigación previa sobre modelización y previsión de la demanda turística y los posibles desarrollos futuros.

En esta revisión del marco actual de conocimientos sobre modelización y previsión de la demanda turística y los posibles desarrollos futuros,se adopta un enfoque narrativo.

Se identifican avances metodológicos significativos en la modelización y previsión de la demanda turística en las dos últimas décadas.

Se resumen las características propias de los diversos métodos aplicados en este campo y se propone una agenda de investigación para futuros trabajos.

This study aims to add to the growing literature on the trade–finance nexus by exploring the interplay between a country's level of financial development, the external finance dependence of firms and their exporting decisions.

The study first develops a theoretical model to motivate the idea that a firm's liquidity (financial) position and its home country's level of financial development act as substitute factors in its export market entry decisions. It then empirically tests whether an improvement in a country's financial development level enhances the number of entrants in the foreign markets and boosts the exports of incumbent exporters using firm-level data of manufacturing firms in India for the period 1993–2020.

Empirical results suggest that a higher level of financial development helps increase the exporting probability of firms that rely more on external finance for their operations. Further, the study finds that the sunk costs-induced hysteresis effect plays a major role in firms' exporting decisions and financial factors don't play a significant role in the exporting activities of incumbent exporters.

The findings suggest that a well-developed financial market is necessary to help more and more firms initiate their foreign market operations. The results underscore that trade-liberalisation measures alone may not increase India's exports and the government must complement them with financial sector reforms.

Studies highlighting the role of financial sector development in helping financially-constrained Indian firms overcome the entry barriers associated with exporting are extremely limited. This study contributes to this nascent literature by conducting an empirical investigation on an extensive database of Indian manufacturing firms. Moreover, in contrast to the previous firm-level studies in this area, this empirical analysis uses the actual values of external finance raised by the firms as a critical factor in determining their extensive and intensive margin of exports instead of the usual balance sheet variables such as liquidity and leverage.

In the present study, a steel lifting lug is replaced with a composite (carbon fiber-reinforced epoxy [CFRP]) lifting lug made of a carbon/epoxy composite. The purpose of this paper was to obtain a composite lifting lug with a higher level of strength that is capable of carrying loads without failure.

The vibration and static behaviors of steel and composite lifting lugs have been investigated using finite element analysis (FEA), ANSYS software. The main consideration in the design of the composite (CFRP) lifting lug was that the displacement of both steel and composite lugs was the same under the same load. Hence, by using the FEA displacement result of the steel lifting lug, the thickness of the composite lifting lug is determined using FEA.

Compared to the steel lifting lug, the composite (CFRP) lifting lug has much lower stresses and much higher natural frequencies. Static behavior was experienced by the composite lifting lug, showing a reduction in von Mises stress, third principal stress and XZ shear stress, respectively, by 48.4%, 34.6% and 89.8%, respectively, when compared with the steel lifting lug. A higher natural frequency of mode shape swaying in X (258.976√1,000 Hz) was experienced by the composite lifting lug when compared to the steel lifting lug (195.935√1,000 Hz). The safe strength of the design composite lifting lug has been proven by FEA results, which showed that the composite (CFRP) lifting lug has a higher factor of safety in all developed stresses than the steel lifting lug. According to von Mises stress, the factor of safety of the composite lifting lug is increased by 76% when compared to the steel lifting lug. The von Mises stress at the edge of the hole in the composite lifting lug is reduced from 23.763 MPa to 20.775 MPa when compared to the steel lifting lug.

This work presents the designed composite (CFRP) lifting lug, which will be able to carry loads with more safety than a steel one.

Nucleic acid testing is an effective method of accurate prevention and control and a key measure to block the spread of the epidemic. However, the fraud in nucleic acid testing occurred frequently during epidemics. This paper aims to provide a viable scheme for the government to strengthen the supervision of nucleic acid testing and to provide a new condition for the punishment for the negative act of the government and the upper limit of the reward for nucleic acid testing institution of no data fraud.

This paper formulates an evolutionary game model between the government and nucleic acid testing institution under four different mechanisms of reward and punishment to solve the issue of nucleic acid testing supervision. The authors discuss the stability of equilibrium points under the four distinct strategies and conduct simulation experiments.

The authors find that the strategy of dynamic reward and static penalty outperforms the strategies of static reward and static penalty, dynamic reward and static penalty, static reward and dynamic penalty, dynamic reward and dynamic penalty. The results reveal the appropriate punishment for the negative act of the government can enhance the positivity of the government's supervision in the strategy of dynamic reward and static penalty, while the upper limit of the reward for nucleic acid testing institution of no data fraud cannot be too high. Otherwise, it will backfire. Another interesting and counterintuitive result is that in the strategy of dynamic reward and dynamic penalty, the upper limit of the penalty for data fraud of nucleic acid testing institution cannot be augmented recklessly. Otherwise, it will diminish the government's positivity for supervision.

Most of the existing evolutionary game researches related to the reward and punishment mechanism and data fraud merely highlight that increasing the intensity of reward and punishment can help improve the government's supervision initiative and can minimize data fraud of nucleic acid institution, but they fall short of the boundary conditions for the punishment and reward mechanism. Previous literature only study the supervision of nucleic acid testing qualitatively and lacks quantitative research. Moreover, they do not depict the problem scenario of testing data fraud of nucleic acid institution regulated by the government via the evolutionary game model. Thus, this study effectively bridges these gaps. This research is universal and can be extended to other industries.

This study aims to investigate the relationship between corporate governance characteristics and the financial performance of both Islamic and conventional banks in the context of an emerging market, i.e. Malaysia.

This study includes 300 bank-year observations from Islamic and conventional banks over the period 2010–2021. The dynamic panel model (generalized method of moments [GMM]) was considered the primary estimation model that solves simultaneity, endogeneity and omitted variable problems as most governance variables are endogenous by nature. Hence, static models are considered biased after conducting the DWH test of endogeneity, and considering dynamic panel GMM is valid proven by Sargan and Hensen and first-order (ARI) and second-order (ARII) tests.

Based on the regression results, the authors discovered that board size, female participation in the board and director remuneration have a significant positive impact on bank performance, whereas board meetings have a significant negative impact. Furthermore, the board governance structure of commercial banks is found to be more passive than that of Islamic banks.

The study’s findings added a new dimension to governance research, which could be a valuable source of knowledge for policymakers, investors and regulators looking to improve existing governance mechanisms for better performance of conventional and Islamic banks.

The goal of this study is to add to the existing literature by focusing on the impact of female board participation and other board governance mechanisms in both conventional and Islamic banks on bank performance.

This paper aims to test the empirical validity of the dynamic trade-off theory in its symmetric and asymmetric versions in explaining the capital structure of a panel of publicly listed US industrial firms over the period from 2013 to 2019. It analyzes the existence of an adjustment of leverage toward its target level and whether the speed of this adjustment is influenced by the debt measure, the model specification or/and the fact that the actual debt ratio is higher or lower than its long-term target level.

This paper uses a quantitative research methodology using panel data analysis under the partial adjustment model and the error correction model using the generalized moment method in first differences and in systems to explore the dynamic nature of firms’ capital structure behavior.

The results show that the effects of the conventional determinants of leverage are globally consistent with the trade-off theory predictions. The dynamic versions confirm that firms exhibit leverage-targeting behavior. Although this speed of adjustment (SOA) depends on the debt and model specifications, it is around 60% on average. The estimated SOA is higher for the market leverage measure compared to the book leverage. The asymmetric adjustment model reveals that firms are more sensitive to reducing leverage than increasing it when they are away from their target; overleveraged firms exhibit approximately 5% faster adjustment than underleveraged firms when book leverage is used.

The originality of this research paper lies in its development and test of an asymmetric model to allow the leverage adjustment speed to vary depending on whether the firm’s debt ratio is above or below its target level and the methodological approach as well as the different model specifications used and the insights generated through the application of rigorous econometric techniques.

Brief introduction on the importance and the need for plastic analysis methods were presented in the beginning section of this review. The plastic method for analysis was considered to be the more advanced method of analysis because of its ability to represent the true behaviour of the steel structures. Then in the following section, a literature analysis has been carried out on the previous investigations done on steel plates, steel beams and steel frames by other authors. The behaviour of them under different types of loading were presented and are under the investigation of innovative new analysis methods.

Structure member connections also have the potential for plastic failure. In this study, the authors have highlighted a few topics to be discussed. The three topics in this study are T-end plate connections to a square hollow section, semi-rigid connections and cold-formed steel storage racks with spine bracings using speed-lock connections. Connection is one of the important parts of a structure that ensures the integrity of the structure. Finally, in this technical paper, the authors introduce some topics related to seismic action. Application of the Theory of Plastic Mechanism Control in seismic design is studied in the beginning. At the end, its in-depth application for moment resisting frames-eccentrically braced frames dual systems is investigated.

When this study involves the design of a plastic structure, the design criteria must involve the ultimate load rather than the yield stress. As the steel behaves in the plastic range, it means the capacity of the steel has reached the ultimate load. Ultimate load design and load factor design are the methods in the range of plastic analysis. After the steel capacity has reached beyond the yield stress, it fulfills the requirement in this method. The plastic analysis method offers a consistent and logical approach to structural analysis. It provides an economical solution in terms of steel weight, as the sections designed using this method are smaller compared with elastic design methods.

The plastic method is the primary approach used in the analysis and design of statically indeterminate frame structures.