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To guide the stable radius clearance choice of water-lubricated bearings for single screw compressors, this paper aims to analyze the effects of turbulence and cavitation on bearing performance under two conditions of specified external load and radius clearance.

A modified Reynolds equation considering turbulence and cavitation is adopted, based on the Jakobsson–Floberg–Olsson boundary condition, Ng–Pan model and turbulent factors. The equation is solved using the finite difference method and successive over-relaxation method to investigate the bearing performance.

The turbulent effect can increase the hydrodynamic pressure and cavitation. In addition, the turbulent effect can lead to an increase in the equilibrium radius clearance. The turbulent region exhibits a higher load capacity and cavitation rate. However, the increased cavitation negatively impacts the frictional coefficient and end flow rate. The impact of turbulence increases as the radius clearance decreases. As the rotating speed increases, the turbulence effect has a greater impact on the bearing characteristics.

The research can provide theoretical support for the design of water-lubricated journal bearings used in high-speed water-lubricated single screw compressors.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2024-0029/

The purpose of this paper is to investigate the performance of bio-based lubricants (BBL), namely, palm mid-olein (PMO) enriched with an antioxidant agent, tertiary-butylhydroquinone (TBHQ) and a viscosity improver, ethylene-vinyl acetate (EVA), in journal bearing (JB) applications.

Samples of the BBL were prepared by blending it with TBHQ and EVA at various blending ratios. The oxidative stability (OS) and viscosity of the BBL samples were examined using differential scanning calorimetry and a viscometer, respectively. Meanwhile, their performance in JB applications was evaluated through the use of a JB test rig with a 0.5 length-to-diameter ratio at various operating conditions.

It was found that the combination of PMO + TBHQ + EVA demonstrated a superior oil film pressure and load-carrying capacity, resulting in a reduced friction coefficient and a smaller attitude angle compared to the use of only PMO or VG68. However, it was observed that the addition of TBHQ and EVA to the PMO did not have a significant impact on the minimum oil film thickness.

The results would be quite useful for researchers generally and designers of bearings in particular.

This study used PMO as the base stock, and its compatibility with TBHQ and EVA was investigated in terms of its OS and viscosity. The performance of this treated BBL was evaluated in a hydrodynamic JB.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2023-0363/

This study is the first to investigate the causal relationship between Bitcoin and equity price returns by sectors. Previous studies have focused on aggregated indices such as S&P500, Nasdaq and Dow Jones, but this study uses mixed frequency and disaggregated data at the sectoral level. This allows the authors to examine the nature, direction and strength of causality between Bitcoin and equity prices in different sectors in more detail.

This paper utilizes an Unrestricted Asymmetric Mixed Data Sampling (U-AMIDAS) model to investigate the effect of high-frequency Bitcoin returns on a low-frequency series equity returns. This study also examines causality running from equity to Bitcoin returns by sector. The sample period covers United States (US) data from 3 Jan 2011 to 14 April 2023 across nine sectors: materials, energy, financial, industrial, technology, consumer staples, utilities, health and consumer discretionary.

The study found that there is no causality running from Bitcoin to equity returns in any sector except for the technology sector. In the tech sector, lagged Bitcoin returns Granger cause changes in future equity prices asymmetrically. This means that falling Bitcoin prices significantly influence the tech sector during market pullbacks, but the opposite cannot be said during market rallies. The findings are consistent with those of other studies that have established that during market pullbacks, individual asset prices have a tendency to decline together, whereas during market rallies, they have a tendency to rise independently. In contrast, this study finds evidence of causality running from all sectors of the equity market to Bitcoin.

The findings have significant implications for investors and fund managers, emphasizing the need to consider the asymmetric causality between Bitcoin and the tech sector. Investors should avoid excessive exposure to both Bitcoin and tech stocks in their portfolio, as this may lead to significant drawdowns during market corrections. Diversification across different asset classes and sectors may be a more prudent strategy to mitigate such risks.

The study's findings underscore the need for investors to pay close attention to the frequency and disaggregation of data by sector in order to fully understand the true extent of the relationship between Bitcoin and the equity market.

This work analyzes female immigrants’ integration in the dimensions of education, labor market participation and fertility in 15 European countries, considering individual characteristics, including cultural background, host countries’ attitudes towards immigrants, the role of women in the family and country-specific integration policy. All these aspects taken together are crucial to understand the main patterns of integration focusing on gender differences.

We focus on second- and first-generation male and female immigrants between the age of 25 and 41, with a length of stay of at least ten years. Enrollment ratios for tertiary education in parents’ countries, the total fertility rate and the female labor force in the mother’s country represent ethnic background. Diversity in the destination regions is captured by local attitudes towards immigrants, the perceived role of women and national policies to integrate migrants [Migrant Integration Policy Index (MIPEX)]. The data are drawn from the European Social Survey (ESS) for 2010–2018. Our results are based on ordinary least squares (OLS) and logit estimates; multilevel analysis was conducted.

We find significant evidence of gender role transmission from mother to daughter; age at immigration seems to be crucial to examine the importance of the culture of origin among immigrants. However, females are responsive to attitudes toward immigrants and gender equality in receiving societies, while integration policies, by defining the set of opportunities, may contribute to both genders’ tertiary education and women’s probability of being in the labor force.

This work underlines that integration policies favoring equal rights as nationals may contribute to both women’s tertiary education and their probability of being in the labor force.

We explore female integration in Europe in the dimensions of education, labor market, fertility and the role of both immigrants’ cultural heritage and specific aspects of destination countries. Previous research, particularly in the USA, has generally focused on some of these features at the expense of a more comprehensive approach. This study builds upon the existing literature and contributes to it by taking a multifaceted approach to female integration in Western Europe, which presents not only an institutional context different from the USA but also some heterogeneity with respect to integration policies and socioeconomic factors.

The data for this case were obtained primarily through a series of in-person interviews in Penang between the authors and Pete Browning (a pseudonym) from 2017 to early 2019. The authors also consulted secondary data sources, including publicly available material on BMax and “Company B”.

This case examines a key decision, or set of decisions, in the life of a small- to medium-sized management consultancy group, namely, whether they might expand their operations in Southeast Asia, and if so, where. These key decisions came in the wake of their having already established a very modest scale presence there, with an operating base on the island of Penang just off the north western coast of Peninsular Malaysia. The initial establishment of a Southeast Asian branch had been somewhat spontaneous in nature – a former colleague of one of the two managing partners in the USA was on the ground in Malaysia and available: he became the local partner in the firm. But the firm had now been eyeing expansion within the region, with three markets under particular consideration (Singapore, Indonesia and Thailand) and a further two (Vietnam and China) also seen as possible targets, though at a more peripheral level. The questions facing the decision makers were “was it time they expand beyond Malaysia?” and “if so, where?”

This case could be used effectively in undergraduate courses in international business. The key concepts on which the case focuses are the factors affecting market entry, particularly the choice of market and the assessment of potential attractiveness such markets offer.

The study aims to explore digital transformation from the viewpoint of human resource management to uncover possible threads of relationship using bibliometric analysis. It also aims to identify the trending research themes within the domains of digital transformation (DT) and human resource management (HRM) collectively.

The research employs a mix of quantitative bibliometric techniques and qualitative content analysis. A corpus of 227 articles retrieved from the Scopus database was analyzed using the R-based Biblioshiny and VOS viewer.

The study shows publication trends, influential authors, leading journals, highly productive institutions, and, countries in the domain of DT and HRM. Co-citation and co-occurrence analysis was undertaken to identify the research clusters, depicting trending research themes that extensively dominate the research under this domain.

This study will serve as a ready reckoner for academicians and business leaders, giving them useful insights to make their road towards digital transformation less challenging with the assistance of human capital.

This study is one of the initial efforts to quantitatively synthesize the results of earlier publications using bibliometric techniques in the domain of DT and HRM together. It will aid researchers in locating research gaps and filling those gaps in the future.

Electric motor heating during biomass recovery and its handling on conveyor is a serious concern for the motor performance. Thus, the purpose of this paper is to design and develop a hardware prototype of master–slave electric motors based biomass conveyor system to use the motors under normal operating conditions without overheating.

The hardware prototype of the system used master–slave electric motors for embedded controller operated robotic arm to automatically replace conveyor motors by one another. A mixed signal based embedded controller (C8051F226DK), fully compliant with IEEE 1149.1 specifications, was used to operate the entire system. A precise temperature measurement of motor with the help of negative temperature coefficient sensor was possible due to the utilization of industry standard temperature controller (N76E003AT20). Also, a pulse width modulation based speed control was achieved for master–slave motors of biomass conveyor.

As compared to conventional energy based mains supply, the system is self-sufficient to extract more energy from solar supply with an energy increase of 11.38%. With respect to conventional energy based \ of 47.31%, solar energy based higher energy saving of 52.69% was reported. Also, the work achieved higher temperature reduction of 34.26% of the motor as compared to previous cooling options.

The proposed technique is free from air, liquid and phase-changing material based cooling materials. As a consequence, the work prevents the wastage of these materials and does not cause the risk of health hazards. Also, the motors are used with their original dimensions without facing any leakage problems.

Many European countries suspended mandatory conscription after the Cold War, and especially between 2000 and 2010. However, with the changing security situation in Europe, more and more countries are considering the re-introduction of the draft. That is why, it is important to evaluate the impact of conscription on draftees, including its effect on fertility outcomes. Additionally, fertility is of particular interest because birth rates have been below replacement levels in most European countries at least in the last two decades. This, combined with the increase in life expectancy, has contributed to aging population and raises concerns about the future economic prospects and sustainability of the continent. Military service could be related to fertility in several ways. Compulsory service for men would affect the marriage market and subsequently child-bearing outcomes. For example, men who serve in the military would have to delay higher education at least by a year, given that they plan to continue their education after high school. One possibility is that this leads to older men meeting younger women if partners meet at college. Alternatively, in case the partners know each other prior to the draft, service could delay marriage by up to a year due to the conscription, postponing planning and having children, and potentially having fewer children as women might be less able or less willing to have a child after a certain age. Finally, some men who plan and would otherwise continue their education might choose to not do so or to further postpone it once they disattach from studying during their service. For some men, this might influence their marital and subsequent fertility outcomes. In either of these scenarios, a draft or its suspension is likely to be connected to fertility.

This study examines the effect of the suspension of the draft in Spain in December 2001 on three fertility outcomes of men that would have been drafted in the absence of the suspension. The author performs the analysis in a difference-in-differences framework. Potential concerns and policy implications are also discussed.

The findings suggest that after the suspension of the draft, individuals started to have their first child earlier given that they decide to have children. Consistent with the overall time trend, they became less likely to have a child and started to have fewer children. However, the age at birth of the first child decreased while the number of children and the likelihood of having a child increased for men relative to women, after compared to before the suspension of the mandatory draft.

The author extends prior literature by investigating the effect of the abolition of compulsory military service in Spain in December 2001 on fertility. This is novel is several ways. First, to the best of the author’s knowledge, previous literature has examined the effect of this Spanish reform only on labor market outcomes prior to men's conscription. Second, even for other countries that terminated the compulsory draft, fertility has been under-studied, providing an opportunity for further exploration. Third, this analysis is based on rich Census data, representative of the population in Spain. Finally, given the inconclusive findings of previous studies for other countries and the proposed re-introduction of the draft in some parts of Europe, additional evidence of the effect of the conscription has important policy implications necessary for the evaluation of future military service policy decisions.

This study aims to improve the automatic leveling performance of tractor body in hilly and mountainous areas by designing a kind of controllable and adaptive leveling mechanism of tractor body.

The mechanism is mainly composed of longitudinal slope leveling mechanism, transverse slope leveling mechanism and control components. According to the tractor body attitude in operation, the longitudinal slope leveling and lateral slope leveling can coordinate to realize the adaptive adjustment of tractor body. For this mechanism, the support mode of the linear three-point support and plane positioning combining is designed, and the leveling method of electromechanical combination is designed. The servo motor controls the longitudinal slope leveling mechanism through the reducer with self-locking function to realize the longitudinal leveling, and the servo driver controls the expansion and contraction of electric cylinder to realize lateral leveling. The designed mode can realize the relative independence and coordination of leveling in different directions.

The performance test results of the leveling mechanism are shown: the mechanism can work normally; the leveling accuracy can reach within 1°; and the leveling accuracy and stability can meet the design requirements. The leveling accuracy and stability of longitudinal slope are higher than that of lateral slope, and the coordination leveling effect of longitudinal slope and lateral slope is better than that of the independent leveling.

This study provides a technical reference for the design of leveling device of agricultural machines and tools in hilly and mountainous areas.

Drawing on new insights from the perspectives and experiences of board members, the purpose of this study is to determine the board attributes that influence board roles in improving the integration of corporate social responsibility (CSR) into corporate governance structures. In total, 10 in-depth semi-structured interviews were conducted with directors of listed Jordanian companies to explore their perceptions of the effect of board of directors' composition on CSR and CSR disclosure (CSRD). The key findings show that boards with a diverse range of directors is essential independent/nonexecutive members, directors with business and/or accounting backgrounds, and foreign members to determine if they aim to better manage their CSR. To take CSR to the next level in the Arab region, we need to strengthen corporate governance mechanisms, and put more pressures on companies to make changes in board composition. For example, we suggest that companies that appoint business-educated and foreign members to their boards tend to engage in more impactful social and environmental-related activities and reflect their sustainable development more effectively. The study responds to calls for further research adopting qualitative methods, such as case studies and interviews in order to obtain a complete and in-depth understanding of the influence of board composition on CSR/CSRD. The findings provide useful insights for practice, policymakers, and future research.