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The purpose of this study is to model steam condensing flows through steam turbine blades and find the most suitable condensation model to predict the condensation phenomenon.

To find the most suitable condensation model, five nucleation equations and four droplet growth equations are combined, and 20 cases are considered for modelling the wet steam flow through steam turbine blades. Finally, by the comparison between the numerical results and experiments, the most suitable case is proposed. To find out whether the proposed case is also valid for other boundary conditions and geometries, it is used to simulate wet steam flows in de Laval nozzles.

The results indicate that among all the cases, combining the Hale nucleation equation with the Gyarmathy droplet growth equation results in the smallest error in the simulation of wet steam flows through steam turbine blades. Compared with experimental data, the proposed model’s relative error for the static pressure distribution on the blade suction and pressure sides is 2.7% and 2.3%, respectively, and for the liquid droplet radius distribution it totals to 1%. This case is also reliable for simulating condensing steam flows in de Laval nozzles.

The selection of an appropriate condensation model plays a vital role in the simulation of wet steam flows. Considering that the results of numerical studies on condensation models in recent years have not been completely consistent with the experiments and that there are still uncertainties in this field, further studies aiming to improve condensation models are of particular importance. As condensation models play an important role in simulating the condensation phenomenon, this research can help other researchers to better understand the purpose and importance of choosing a suitable condensation model in improving the results. This study is a significant step to improve the existing condensation models and it can help other researchers to gain a revealing insight into choosing an appropriate condensation model for their simulations.

Learning as the way in which labor acquire new knowledge and skills has important strategic implications for the competitive advantage of an organization. The purpose of this paper is to present an agent-based modeling (ABM) approach to investigate the learning behavior of workers. The effect of interactions among different workers as well as the factors affecting the workers’ learning behavior is assessed using the proposed ABM approach.

For this purpose, the processes through which the competency value of worker is changed are understood and the workers’ learning behavior is modeled, taking account of various influencing factors such as knowledge flow, social ability to teach and forgetting factor.

The proposed model is implemented on a real steel structure project to evaluate its applicability and performance. The variation in the competency value of different workers involved in the project is simulated over time taking account of all the influencing factors using the proposed ABM approach.

In order to assess the effect of interactions among welders as well as the welders’ characteristics on their learning behavior, the competence value of different welders is evaluated.

This research presents an ABM approach to investigate the workers’ learning behavior. To evaluate the performance of the proposed ABM approach, it was implemented on a real steel structure project. The learning behavior of different welders (agents) was simulated taking account of their interactions as well as the factors affecting the welders’ learning behavior. The project involved the welding of a 240-ton steel structure. The initial project duration was estimated as 100 days. In this project, it has been planned to execute the welding process using three different welders namely welder A, B and C.

In May 2014, a new reform in the health sector of Iran was implemented called “health evolution plan.” In the first phase of this reform, the government reduced out-of-pocket payments for service delivery by paying subsidies to the services and after that a revision was done to the medical services values book to improve equity and increase motivation of health professions. One of the affected services in this reform was coronary artery bypass surgery. The purpose of this paper is to show the effects of HEP on costs of coronary artery bypass surgery.

A before-after study was done for this purpose and 167 patients’ total costs and out-of-pocket payments were calculated for the years 2013 (before) and 2014 (after) the reform in three private hospitals of Rasht city, Iran. Econometrics models were estimated after adjustment of confounding variables.

The results of this study showed that surgery costs increased significantly from $1,643.3 to 2,119.5. Nursing and other costs increased significantly from $290.3 to 414.2 and anesthetize costs increased from $619.2 to 947.01. The results of regression model showed that total costs increased $3,008.6 after adjustment of confounders (p-value=0.037). However, no significant changes were found for out-of-pocket payments and out-of-pocket percentage.

The study findings revealed that HTP was not successful enough in financial protection in the private sector.

The purpose of this paper is to present the factors affecting purchase intention of foreign food products in the Iranian context.

The present study is a survey research and has a quantitative approach. According to Morgan’s table, 384 people were selected as sample size. Based on an in-depth review of previous literature, a comprehensive set of sub-factors related to customer’s purchase intention was extracted to design questionnaire. Then, exploratory factor analysis and confirmatory factor analysis were applied to identify and confirm the factors affecting purchase intention of foreign food products in Iran.

The obtained results illustrate 13 factors as follows: “corporate social responsibility,” “customer knowledge and awareness,” “perceived risk,” “retailer’s commercial image,” “customer’s personality characteristics,” “social identity,” “product features,” “attitude,” “country-of-origin,” “perceived value,” “subjective norm,” “loyalty” and “perceived behavioral control.”

As the present research was carried out in the Iranian context, the generalization of the findings is limited and caution should be taken in this regard.

The identified factors could contribute to international food companies and retailers to understand customers’ expectations and to gain more market share in Iran.

The originality of this paper lies in identifying a comprehensive set of the factors affecting purchase intention of foreign food products and developing the theoretical literature in the field of the present research.

This study aims to investigate the feasibility of proposed microgrid (MG) that comprises photovoltaic, wind turbines, battery energy storage and diesel generator to supply a residential building in Grindelwald which is chosen as the test location.

Three operational configurations were used to run the proposed MG. In the first configuration, the electric energy can be vended and procured utterly between the main-grid and MG. In the second configuration, the energy trade was performed within 15 kWh as the maximum allowable limit of energy to purchase and sell. In the third configuration, the system performance in the stand-alone operation mode was investigated. A whale optimization technique is used to determine the optimal size of MG in all proposed configurations. The cost of energy (COE) and other measures are used to evaluate the system performance.

The obtained results revealed that the first configuration is the most beneficial with COE of 0.253$/KWh and reliable 100%. Furthermore, the whale optimization algorithm is sufficiently feasible as compared to other techniques to apply in the applications of MG.

The value of the proposed research is to investigate to what extend the integration between MG and main-grid is beneficial economically and technically. As opposed to previous research studies that have focused predominantly only on the optimal size of MG.

This paper aims to examine the challenges faced by health-care leadership in teaching hospitals in attaining accreditation for their institutions.

This paper is based on a study of current literature on health-care leadership, hospital accreditation and quality of patient care and identifies the challenges facing health-care leadership in attaining accreditation for teaching hospitals.

Based on a review and analysis of literature, infrastructure, finance, legal support, workforce recruitment and training, documentation and technology are identified as challenges faced by health-care leadership in teaching hospitals. The key challenges facing health-care leadership with respect to medical education and clinical research are found to be integration of education into hospital operations, compliance with all regulatory and professional requirements and adequacy of resources in executing research programs.

This study draws the attention of health-care leadership in teaching hospitals on the challenges they face in obtaining accreditation for their institutions so that they may develop appropriate strategies to overcome them.

This study introduces a comprehensive bibliometric analysis of the foreign direct investment (FDI) literature by multinational corporations (MNCs) focusing on emerging economies to identify the most influential authors, journals and articles in FDI research and reveals the fields' conceptual and intellectual structures. The purpose of this paper is to address these issues.

The study analyzed 533 articles published between 1974 and 2020 in 226 academic journals indexed in the Web of Science (WoS) and Scopus databases. We used the R language for statistical computing to map author collaboration, co-word and develop a conceptual and intellectual map of the field.

The results show that, although the FDI literature has many authors, few dominate the field. The International Business Review (IBR) and International Journal of Emerging Markets (IJoEM) are the main sources of the publications. Moreover, bibliometric laws show that our dataset follows the Lotka law of scientific productivity and Bradford law of scattering, identifying the core journals. Finally, FDI by MNCs in emerging economies research is divided into four sub-research themes related to (1) FDI determinants, (2) entry mode, (3) MNCs and FDI performance and (4) the internationalization process.

The current article provides several starting points for practitioners and researchers investigating FDI. It contributes to broadening the vision of the field and offers recommendations for future studies.