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The purpose of this study was to introduce three-dimensional printing (3DP) of functionally graded sandwich foams (FGSFs). This work was continued by predicting the mechanical buckling and free vibration behavior of 3DP FGSFs using experimental and numerical analyses.

Initially, hollow glass microballoon-reinforced high-density polyethylene-based polymer composite foams were developed, and these materials were extruded into their respective filaments. These filaments are used as feedstock materials in fused filament fabrication based 3DP for the development of FGSFs. Scanning electron microscopy analysis was performed on the freeze-dried samples to observe filler sustainability. Furthermore, the density, critical buckling load (P_cr), natural frequency (f_n) and damping factor of FGSFs were evaluated. The critical buckling load (P_cr) of the FGSFs was estimated using the double-tangent method and modified Budiansky criteria.

The density of FGSFs decreased with increasing filler percentage. The mechanical buckling load increased with the filler percentage. The natural frequency corresponding to the first mode of the FGSFs exhibited a decreasing trend with an increasing load in the pre-buckling regime and an increase in post-buckled zone, whereas the damping factor exhibited the opposite trend.

The current research work is valuable for the area of 3D printing by developing the functionally graded foam based sandwich beams. Furthermore, it intended to present the buckling behavior of 3D printed FGSFs, variation of frequency and damping factor corresponding to first three modes with increase in load.

This paper aims to investigate the morphology and tensile properties of SAC305 solder alloy under the influence of microwave hybrid heating (MHH) for soldering at different microwave parameters.

Si wafer was used as susceptor in MHH for solder reflow. Microwave operating power for medium and high ranging from 40 to 140 s reflow time was used to investigate their effect on the microstructure and strength of SAC305/Cu solder joints. The morphology and elemental composition of the intermetallic compound (IMC) joint were evaluated on the top surface and cross-sectional view.

IMC formation transformed from scallop-like to elongated scallop-like structure for medium operating power and scallop-like to planar-like structure for high operating power when exposed to longer reflow time. Compositional and phase analysis confirmed that the observed IMCs consist of Cu₆Sn₅, Cu₃Sn and Ag₃Sn. A thinner IMC layer was formed at medium operating power, 80 s (2.4 µm), and high operating power, 40 s (2.5 µm). The ultimate tensile strength at high operating power, 40 s (45.5 MPa), was 44.9% greater than that at medium operating power, 80 s (31.4 MPa).

Microwave parameters with the influence of Si wafer in MHH in soldering have been developed and optimized. A microwave temperature profile was established to select the appropriate parameter for solder reflow. For this MHH soldering method, the higher operating power and shorter reflow time are preferable.

In the first two parts of this paper attention has been directed to determination of the stresses in a disk as dependent upon elastic and plastic strain, including creep effects which may occur at the rim region. The problem has so far, however, been treated without complication introduced by the blade fastenings and therefore, in effect, the disk has been investigated as far as the base of the blade grooves or slots. It has, however, been realized that the projections forming blade root fastenings present their own problems, differing from those of the disk, and these problems have been left to be dealt with in this third portion of the paper. Nevertheless, in Parts I and II the fact that the root fastenings applied an interrupted radial loading at the outside, and not a perfectly distributed load as assumed in the analysis, was not overlooked.

The subject of cyber‐slacking has prompted many organizations to respond by enforcing or implementing policies that restrict internet access. The purpose of this paper is to empirically examine the impact of four internet monitoring policies on cyber‐slacking and work satisfaction.

Employees working in medium‐size organizations in Lebanon were surveyed. Chi‐square tests, correlation, ANOVA, and regression analysis were used to test the hypothesis.

Results indicated that having a free internet access had a positive relation with cyber‐slacking, leading to an increase in work satisfaction. The survey also indicated relationship with demographic factors.

Although the research provides useful insight on cyber‐slacking and monitoring policies, it is nevertheless restricted to Lebanese companies.

This paper adds to the literature on cyber‐slacking by empirically testing the effect of different monitoring policies.

This chapter stands for justification of growing demand for supporting new theoretical and methodological approaches in development of an actual green economy’s financial framework taking into consideration modern growing risks in the ecological, economic, social, and geopolitical environments. A notable increase in environmental expenditures of both national economies and international financial institutions is determined by the global state of the economy. The climate change has been caused by escalating the energy supply struggle, the nature exhaustion, and the need for providing balance to the market stating green economy regulators. The main aim of this chapter is to study the trends and the key state green finance regulation points. The research goal could be achieved through highlighting the nature of green finance and its framework; studying the concept of green finance and innovative financial tools’ development, providing green economy’s development; and spotting trends and imperatives of regional regulation of green finance. This chapter highlights the necessity for implementing complex systemic and methodologic approaches in making the green finance framework, summarizing leading practices in green funding and green economy’s funds raising, considering limits in green finance tools’ utilization in current conditions, strengthening the power of both federal and regional authorities in solving financial problems of energy saving, and extending the practices of companies and institutions’ green financial tools’ utilization. The necessity for a green sustainable development across the globe has driven this research to use different types of instruments to point out the benefits of such a development. In addition, green finance state regulation tools have been proposed.

The purpose of this paper is to identify and evaluate critically the impacts associated with the implementation of electronic monitoring (EM) of accused and convicted persons on society based on the foreign experience and compare these findings with the original research results on EM in the Slovak Republic.

This paper elaborates the secondary data of previous researches in Scotland, Sweden and Florida in the USA. Secondary research is based on in-depth analysis of articles, reports and studies searched via database of Google, Scopus and Science Direct. Based on the studies processed by a causal and qualitative analysis, the authors identify the benefits and risks of EM influencing community life in Europe and the USA. The additional sources of secondary data are the Statistical Yearbook of Ministry of Justice of Slovak Republic, the content of the original law (including relevant amendments) that introduced EM into the Slovak criminal justice system and data on the application of EM in Slovakia provided by the Ministry of Justice. Subsequently, this paper presents the original research findings about the EM implementation in the Slovak Republic. The primary data were conducted via interviews with the representatives of Ministry of Justice, and through the national survey of opinions of judges, probation and mediation officers. The authors used the descriptive statistics and the statistical deduction methods.

The key finding of the paper is that there is a very narrow border between EM as blessing and disguise for community involved. Setting proper measures to protect the community, targeted communication and support with attendance of professionals (e.g. mediator and psychologist) for community members might help to avoid possible risks and support the benefits related with EM implementation, namely, social and economic inclusion of offenders, maintaining family and community tights, reducing recidivism or protection of sensitive sites.

To support the acceptation of EM by local community, the authors recommend to perceive sensitively community involvement and consider potential risks related with EM implementation; to suggest the proper measures to protect the community; and to develop better or targeted communication oriented towards increasing awareness or establishment supporting groups with attendance of professionals (e.g. mediator and psychologist) that might help to avoid possible risks and support the benefits related with EM implementation.

This paper compares experience with EM based on the secondary data of previous researches in Scotland, Sweden and Florida in the USA. Subsequently, it presents the unique data about the implementation of EM in the Slovak Republic. The topic of EM is still vastly underrated in the literature, and there is a lack of empirical data, so this paper as a combination of case studies and original research could be very helpful in the efficient implementation of EM and setting the proper measures.

Online higher education has rapidly expanded in the United States and displays a great opportunity for growth. Coupled with the growth of e-learning is the need for adjunct faculty to satisfy the need for additional online classes. Despite the importance of online adjunct faculty, little research has been performed to determine their work experiences. This quantitative, correlational study investigated the predictive relationship between the perceived use of transformational, transactional, and laissez-faire leadership behaviors on the extra effort of adjunct faculty who facilitate online classes at a for-profit university in the United States. In a further investigation, the researcher investigated the variable of job satisfaction to determine if it mediated the relationship between leadership style and extra effort. The researcher used the Multifactor Leadership Questionnaire and Spector’s Job Satisfaction survey to collect data used in inferential analysis. The researcher performed a stepwise multiple regression and a Baron and Kenny mediation analysis to answer the research questions. The results showed perceived transformational leadership behaviors displayed a statistically significant positive predictive relationship with extra effort, and job satisfaction was a partial mediator between the relationship of transformational leadership and extra effort. The results suggest transformational leadership is beneficial to the extra effort put forth by the sample of adjunct faculty who teach online classes.

The most enduring measure of how individuals make personal decisions affecting their health and safety is the compensating wage differential for job safety risk revealed in the labor market via hedonic equilibrium outcomes. The decisions in turn reveal the value of a statistical life (VSL), the value of a statistical injury (VSI), and the value of a statistical life year (VSLY), which have both mortality and morbidity aspects that we describe and apply here. All such tradeoff rates play important roles in policy decisions concerning improving individual welfare. Specifically, we explicate the recent empirical research on VSL and its related concepts and link the empirical results to the ongoing examinations of many government policies intended to improve individuals' health and longevity. We pay special attention to recent issues such as the COVID pandemic and newly emerging foci on distributional consequences concerning which demographic groups may benefit most from certain regulations.

This study aims to examine the effect of the Internet on irrigation system adoption. The authors implement the most extensive household survey of irrigation arrangements ever conducted in rural China and also exploit a public program to improve the quality of distance education in rural middle schools, which has led to plausibly exogenous variation in Internet access across rural districts.

The authors present a conceptual framework highlighting the transmission mechanisms whereby Internet access may affect irrigation system selection and identify direct effects through agricultural production and an indirect effect through non-agricultural production. To examine the effect of the Internet on irrigation system adoption, we implement the most extensive household survey of irrigation arrangements ever conducted in rural China. We also exploit a public program to improve the quality of distance education in rural middle schools, which has led to plausibly exogenous variation in Internet access across rural districts.

The authors find evidence to suggest that Internet access can effectively reduce information frictions and searching costs in the non-agricultural labor market, thus increasing rural households' participation in non-farm work. To save more hours from agricultural production, rural households select more labor-saving irrigation systems.

This study’s findings have important implications for the ongoing policy debate over government investment in Internet infrastructure to improve agricultural development in rural and isolated areas.