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Material extrusion-based additive manufacturing is a prominent manufacturing technique to fabricate complex geometrical three-dimensional (3D) parts. Despite the indisputable advantages of material extrusion-based technique, the poor surface and subsurface integrity hinder the industrial application of this technology. The purpose of this study is introducing the hot air jet treatment (HAJ) technique for surface treatment of additive manufactured parts.

In the presented research, novel theoretical formulation and finite element models are developed to study and model the polishing mechanism of printed parts surface through the HAJ technique. The model correlates reflow material volume, layer width and layer height. The reflow material volume is a function of treatment temperature, treatment velocity and HAJ velocity. The values of reflow material volume are obtained through the finite element modeling model due to the complexity of the interactions between thermal and mechanical phenomena. The theoretical model presumptions are validated through experiments, and the results show that the treatment parameters have a significant impact on the surface characteristics, hardness and dimensional variations of the treated surface.

The results demonstrate that the average value of error between the calculated theoretical results and experimental results is 14.3%. Meanwhile, the 3D plots of Ra and Rq revealed that the maximum values of Ra and Rq reduction percentages at 255°C, 270°C, 285°C and 300°C treatment temperatures are (35.9%, 33.9%), (77.6%,76.4%), (94%, 93.8%) and (85.1%, 84%), respectively. The scanning electron microscope results illustrate three different treatment zones and the treatment-induced and manufacturing-induced entrapped air relief phenomenon. The measured results of hardness variation percentages and dimensional deviation percentages at different regimes are (8.33%, 0.19%), (10.55%, 0.31%) and (−0.27%, 0.34%), respectively.

While some studies have investigated the effect of the HAJ process on the structural integrity of manufactured items, there is a dearth of research on the underlying treatment mechanism, the integrity of the treated surface and the subsurface characteristics of the treated surface.

This paper aims to investigate the effect of centrifugal disk finishing (CDF) technique on the surface and subsurface characteristics of the fused deposited modeling (FDM) parts in both theoretical and experimental aspects. From theoretical aspect, a novel theoretical model is developed as a function of layer deposition orientation, layer thickness, finishing working time, density ratio and hardness ratio to estimate the surface roughness profile of FDM part at different finishing conditions and finishing time intervals. Meanwhile, from the experimental aspect, an experimental campaign was performed under different mechanical and mechanical-chemical finishing conditions to verify the theoretical model and also assess the surface and subsurface characteristics of the polished parts.

The theoretical model commences with an approximation of surface profile of the FDM part through a sequence of parabola arcs, continues with the calculation of reference line and machined surface profile and leads to a formulation of surface roughness of as-printed and polished surface. In the experimental section, the FDM parts are polished under dry, pure water, 25% and 50% volumetric aqueous acetone solutions finishing conditions through CDF technique.

The comparison between experimental and theoretical results reveals 9% mean absolute error between theoretical and experimental results. Meanwhile, Rq reduction percentage of polished parts under dry, pure water, 25% and 50% aqueous acetone solutions are 66.1%, 54.5%, 56.9% and 67.2%, respectively. The scanning electron microscopy results reveal severe layer damage in dry finishing condition, while the application of 50% aqueous acetone as a polishing solution completely eliminates layer damage. Another promising finding was sticky material phenomenon on the surface of polished part under 25% finishing condition. The Shore hardness test illustrates that the surface hardness improvement of the polished parts under dry, pure water, 25% and 50% aqueous acetone solutions finishing conditions are 8.4%, 2.25%, 4.36% and 10.8%, respectively. The results also revealed that the dimension variation of polished parts under dry, pure water, 25% and 50% aqueous acetone solutions are 0.634%, 0.525%, 0.545% and 0.608%, respectively. The edge profile radius of the as-printed part is 134 µm, while the edge profiles radius of the polished parts under dry, pure water, 25% aqueous acetone solution and 50% aqueous acetone solution are 785.5 µm, 545.5 µm, 623.5 µm and 721.5 µm, respectively, at the polishing time of 720 min.

This paper fulfills an identified need to study the benefits of the mechanical-chemical polishing technique in comparison to mechanical and chemical polishing strategy of the FDM parts for the first time. Beside the experimental campaign, the novel analytical formulation of surface roughness as a function of mechanical properties of abrasive media and FDM part and finishing specifications provides a valuable insight in the case of material-removal processes.

Today’s, supply chain production and distribution of products to improve the customer satisfaction in the shortest possible time by paying the minimum cost, has become the most important challenge in global market. On the other hand, minimizing the total cost of the transportation and distribution is one of the critical items for companies. To handle this challenge, this paper aims to present a multi-objective multi-facility model of green closed-loop supply chain (GCLSC) under uncertain environment. In this model, the proposed GCLSC considers three classes in case of the leading chain and three classes in terms of the recursive chain. The objectives are to maximize the total profit of the GCLSC, satisfaction of demand, the satisfactions of the customers and getting to the proper cost of the consumers, distribution centers and recursive centers.

Then, this model is designed by considering several products under several periods regarding the recovery possibility of products. Finally, to evaluate the proposed model, several numerical examples are randomly designed and then solved using non-dominated sorting genetic algorithm and non-dominated ranking genetic algorithm. Then, they are ranked by TOPSIS along with analytical hierarchy process so-called analytic hierarchy process-technique for order of preference by similarity to ideal solution (AHP-TOPSIS).

The results indicated that non-dominated ranked genetic algorithm (NRGA) algorithm outperforms non-dominated sorting genetic algorithm (NSGA-II) algorithm in terms of computation times. However, in other metrics, any significant difference was not seen. At the end, to rank the algorithms, a multi-criterion decision technique was used. The obtained results of this method indicated that NSGA-II had better performance than ones obtained by NRGA.

This study is motivated by the need of integrating the leading supply chain and retrogressive supply chain. In short, the highlights of the differences of this research with the mentioned studies are as follows: developing multi-objective multi-facility model of fuzzy GCLSC under uncertain environment and integrating the leading supply chain and retrogressive supply chain.

The purpose of this paper is to examine the impact of human resource management (HRM) practices on organizational performance.

A total of 300 employees from a public university comprising of both academicians and support staff responded to the survey. The survey questionnaire had 46 items covering selected HRM practices and university performance.

The study has found that human resource practices: recruitment, training, performance appraisal, career planning, employee participation, job definition and compensation have a significant relationship with university performance.

The results come from a cross-sectional study which was done at the convenience of the researcher. The results may not be generalized across the country. The application of the results to other universities must be done with maximum care.

If the university is to increase its performance to higher levels, it should emphasize more on job definition, training and employee participation. Some improvement needs to be done on the other HRM practices-recruitment, performance appraisal, career planning and compensation in order to increase their effectiveness on the university performance.

Most studies on impact of HRM practices on firm performance have focussed on private sectors in Malaysia. In other countries, the studies have focussed only on academicians as a sample. This study has attempted to add to the body of knowledge on the impact of HRM practices on university performance in Malaysia combining both the academicians and administration staff.

The purpose of this paper is to examine the mediating role of employee competencies in the association between human resource development (HRD) practices and organizational performance.

An integrated research model was developed by combining principal factors from existing literature. Data were collected through questionnaire from 600 employees of the selected hotels. The validity of the model and hypotheses was tested using structural equation modeling. The reliability and validity of the dimensions are established through confirmatory factor analysis.

The results indicate that some HRD practices impact organizational performance through their influence on employee competencies. The study further revealed that employee competencies mediate the association between HRD practices and organizational performance.

The research was undertaken in the hotel industry and the analysis based on cross-sectional data which cannot be generalized across a broader range of sectors.

The findings of the study have the potential to help stakeholders and management of hotels in adopting properly and well-articulated HRD practices to stimulate positive behavior in individuals and impact their knowledge, skills and attitudes.

This study extends the literature by adducing evidence that employee competencies mediated the association between HRD practices and organizational performance of the hotel industry in Ghana.

The purpose of this paper is to examine the mediating role of employee performance in the association between human resource development (HRD) practices and organizational performance.

An integrated research model was developed by combining principal factors from existing literature. Data were collected through questionnaire from 700 employees of the selected pharmaceutical industries. The validity of the model and hypotheses was tested using structural equation modeling. The reliability and validity of the dimensions are established through confirmatory factor analysis.

The results indicate that some HRD practices influence organizational performance through their impact on employee performance. The study further revealed that employee performance mediates the association between HRD practices and organizational performance.

The research was undertaken in the pharmaceutical industry and the analysis is based on cross-sectional data, which cannot be generalized across a broader range of sectors.

The findings of the study have the potential to help policy makers, stakeholders and management of pharmaceutical industries in adopting properly and well-articulated HRD practices to enhance the quality of human capital and create sustainable competitive advantage.

This study extends the literature by adducing evidence empirically that employee performance mediated the association between HRD practices and organizational performance of the pharmaceutical industry in Ghana.

The purpose of this paper is to examine the mediating role of employee competencies in the relationship between human resource management (HRM) practices and organizational performance.

An integrated research model was developed by combining principal factors from existing literature. Data were collected through questionnaire from 600 employees of the selected hotels. The validity of the model and hypotheses was tested using structural equation modeling. The reliability and validity of the dimensions are established through confirmatory factor analysis.

The results indicate that some HRM practices impact organizational performance through their influence on employee competencies. The study further revealed that employee competencies mediate the relationship between HRM practices and organizational performance.

The research was undertaken in the hotel industry and the analysis based on cross-sectional data which cannot be generalized across a broader range of sectors and international environment.

The findings of the study have the potential to help policy makers, stakeholders and management of hotels in adopting proper and well-articulated HRM practices in building human capital and stimulating the necessary behaviors that create advantage for the organization.

This study extends the literature by empirically adducing evidence that employee competencies mediated the relationship between HRM practices and organizational performance of the hotel industry in Ghana.

The purpose of this paper was to determine the effects of the spinach extract and kiwi flavor on the physicochemical and organoleptic properties of yogurt.

A total of 48 yogurt samples including yogurts flavored with kiwi flavor (1, 2 and 4 percent) and colored with spinach extract (1.25, 2.5 and 4 percent) and a control yogurt (no kiwi flavor or spinach extract) were evaluated for chemical, physical and sensory properties during 21 days of storage. Data were analyzed by ANOVA using statistical analysis system.

Statistically significant differences (p<0.05) were found between the control and kiwi-spinach yogurts in terms of viscosity and syneresis. The addition of the spinach extract to yogurt resulted in an increase in the syneresis, and a decrease in the viscosity. During the storage, the values of the titratable acidity, viscosity and syneresis of yogurt samples increased, while pH decreased significantly (p<0.05). Yogurt enriched with 4 percent spinach extract and 4 percent kiwi flavor was more acceptable than the other samples, and high scored with respect to overall acceptability by panelists.

No research had been done to formulate and compare the sensory and physicochemical properties of kiwi-spinach yogurt in Iran.

The current manuscript is focused on evaluating the capabilities of green practices that affect various business performance (BP) parameters of small and medium scale Indian manufacturing enterprises (SME’s). This study aims to obtain multiple significant factors that influence the implementation of green practices.

The manuscript focuses on statistical testing of responses obtained from 168 Indian SMEs to determine the relationship between input parameters and BP parameters. This paper starts with deploying tests such as Cronbach alpha and inter-item covariance test to obtain confidence in data collected, followed by various statistical tests such as Pearson correlation, multiple regression, canonical correlation to extract various significant factors the study. Further Games-Howell post hoc test is deployed to evaluate the significant improvements in BP gained over a reasonable duration of time. Finally, a discriminant validity test is used to find out the success or failure of the organizations that participated in the survey.

This research contributes to the holistic effect of green manufacturing (GM) toward gaining improvements in terms of different BP parameters taken for the study. It has been found that various input factors such as customer attributes, adoption of new technology, social pressure and government pressure are the main parameters for GM implementation. Further, it is observed that those at the maturity phase of GM implementation are reaping higher benefits than the organizations at the transition and stability phase.

The current study has been accomplished in Indian SME manufacturing organizations to investigate the effects of GM implementation in the organization. Although research findings imply the effective use of green practices within the organization to reap BP parameters and improve the market’s competitive image, the study cannot be generalized and can be used as an insight for both academicians and end-users in understanding the overall achievements of GM.