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This study aims to perform a comprehensive investigation to model the thermal characteristics of a coupled conduction-radiation heat transfer in a two-dimensional irregular enclosure including a triangular-shaped heat source.

For this purpose, a promising hybrid technique based on the concepts of blocked-off method, FVM and DOM is developed. The enclosure consists of several horizontal, vertical and oblique walls, and thermal conductivity within the enclosure varies directly with temperature and indirectly with position. To simplify the complex geometry, a promising mathematical model is introduced using blocked-off method. Emitting, absorbing and non-isotropic scattering gray are assumed as the main radiative characteristics of the steady medium.

DOM and FVM are, respectively, applied for solving radiative transfer equation (RTE) and the energy equation, which includes conduction, radiation and heat source terms. The temperature and heat flux distributions are calculated inside the enclosure. For validation, results are compared with previous data reported in the literature under the same conditions. Results and comparisons show that this approach is highly efficient and reliable for complex geometries with coupled conduction-radiation heat transfer. Finally, the effects of thermo-radiative parameters including surface emissivity, extinction coefficient, scattering albedo, asymmetry factor and conduction-radiation parameter on temperature and heat flux distributions are studied.

In this paper, a hybrid numerical method is used to analyze coupled conduction-radiation heat transfer in an irregular geometry. Varying thermal conductivity is included in this analysis. By applying the method, results obtained for temperature and heat flux distributions are presented and also validated by the data provided by several previous papers.

Based on the resource-based view and dynamic capabilities theory, this study aims to examine the complementarity between market orientations and launch proficiency as a driver of new product performance.

In this research, an on-site survey of Iranian, research and development- intensive, manufacturing firms was carried out to examine the proposed hypotheses. Based on the 179 workable survey responses, a covariance-based structural equation modeling was applied to verify the proposed theoretical model.

The empirical findings reveal that the effects of market orientation or launch proficiency alone are not significant while the complementarity between them significantly influences new product performance. These research outcomes suggest that this complementarity leads to a bidirectional co-specialization relationship in firms, promoting both market intelligence generation processes and product-launch capabilities, and therefore resulting in superior new product performance.

The current characterization of the resource-based theory signifies that strategic resources merely have potential value and actualizing this value needs complementary organizational capabilities. Furthermore, the literature notably lacks empirical findings supporting these complementarities. Therefore, the findings concerning the bidirectional co-specialization between market orientation and launch proficiency not only provide empirical support for the dynamic capabilities theory but also address recent research calls to identify and calibrate the importance of dynamic capabilities for leveraging market orientation on new product performance.

The purpose of this paper is to determine the quality gap of university services in the behavioral science faculties of the University of Tehran (Iran).

In the current research, 300 students of five behavioral science faculties – Psychology and Educational Science, Social Science, Economics, Physical Education and Sport Science, Management, Entrepreneurship – in the University of Tehran (Iran), were chosen randomly and completed the SERVQUAL questionnaire. This questionnaire consists of two parts regarding customer's perceptions and expectations about the quality of service. SERVQUAL questionnaire measures the five aspects of service which include assurance, responsiveness, empathy, reliability and tangibles. Therefore, the quality gap of the services of behavioral science faculties was determined according to differences between the students' perceptions and expectations. In order to analyze research data, descriptive statistics, t‐Student and ANOVA analysis were conducted.

The results demonstrated that in three of the five SERVQUAL dimensions (tangibles, reliability, and empathy), there was a negative quality gap (p<0.05). Thus, improvements are needed across three above‐mentioned dimensions. Also, there were no significant differences between perceptions and expectations of students based on their gender, degree and field of study.

The current research was conducted among behavioral science faculties of the University of Tehran, so the results are limited to these faculties, not to the whole university.

There are limited researches that consider service quality in Iranian higher education. However, for the first time, the service quality of behavioral science faculties of the University of Tehran was measured by the SERVQUAL in this research.

Many people have been dying as a result of medical errors. Offering clinical learning can lead to better medical care. Clinics have conventionally incorporated direct modality to teach personnel. However, they are now starting to take electronic learning (e-learning) mechanisms to facilitate training at work or other suitable places. The objective of this study is to identify and prioritize the medical learning system in developing countries. Therefore, this paper aims at describing a line of research for developing medical learning systems.

Nowadays, organizations face fast markets' changing, competition strategies, technological innovations and accessibility of medical information. However, the developing world faces a series of health crises that threaten millions of people's lives. Lack of infrastructure and trained, experienced staff are considered essential barriers to scaling up treatment for these diseases. Promoting medical learning systems in developing countries can meet these challenges. This study identifies multiple factors that influence the success of e-learning systems from the literature. The authors have presented a systematic literature review (SLR) up to 2019 on medical learning systems in developing countries. The authors have identified 109 articles and finally selected 17 of them via article choosing procedures.

The paper has shown that e-learning systems offer significant advantages for the medical sector of developing countries. The authors have found that executive, administrative and technological parameters have substantial effects on implementing e-learning in the medical field. Learning management systems offer a virtual method of augmented and quicker interactions between the learners and teachers and fast efficient instructive procedures, using computer and Internet technologies in learning procedures and presenting several teaching-learning devices.

The authors have limited the search to Scopus, Google Scholar, Emerald, Science Direct, IEEE, PLoS, BMC and ABI/Inform. Many academic journals probably provide a good picture of the related articles, too. This study has only reviewed the articles extracted based on some keywords such as “medical learning systems,” “medical learning environment” and “developing countries.” Medical learning systems might not have been published with those specific keywords. Also, there is a requirement for more research with the use of other methodologies. Lastly, non-English publications have been removed. There could be more potential related papers published in languages other than English.

This paper helps physicians and scholars better understand the clinical learning systems in developing countries. Also, the outcomes can aid hospital managers to speed up the implementation of e-learning mechanisms. This research might also enable the authors to have a role in the body of knowledge and experience, so weakening the picture of the developing country's begging bowl is constantly requesting help. The authors hoped that their recommendations aid clinical educators, particularly in developing countries, adopt the trends in clinical education in a changing world.

This paper is of the pioneers systematically reviewing the adoption of medical learning, specifically in developing countries.

Selecting a suitable contract to outsource construction projects is an ongoing concern for project managers and organizational directors. This study aims to propose a comprehensive model to manage the risks of outsourced construction project contracts.

To employ the proposed model, firstly, the types of contracts and risks in the organization should be identified, then, to prioritize the contracts, the identified risks are considered as criteria. After receiving the experts' opinions, the best–worst method (BWM) integrated with grey relation analysis (GRA) method was used to prioritize the contracts. BWM and GRA are multi-criteria decision-making methods with different approaches and applications. In the current study, BWM has been employed to calculate the weights of criteria because it has better performance than other methods such as the analytic hierarchy process (AHP). After calculating the weights of criteria, the GRA method has been utilized for ranking the alternatives.

According to the results obtained from the case study, the cost plus award fee contract is the most suitable alternative for outsourcing construction projects. The proposed methodology can be practically applied through different types of the projects such as construction or “engineering, procurement and construction”.

To the best of our knowledge, this is the first time a conceptual model has been proposed to select an appropriate contract for construction projects. Also, for the first time, the BWM integrated with GRA method has been used to prioritize project contracts based on the potential risks. The proposed model can contribute to project managers for selecting a suitable contract with the least risk in construction projects.

This paper aims to investigation of processes for Pb²⁺ elimination from water/wastewater as a significant public health issue in many parts of world. The removal of Pb²⁺ ions by various nanocomposites has been explained from water/wastewaters. ZnO-based nanocomposites, as eco-friendly nanoparticles with unique physicochemical properties, have received increased attention to remove Pb²⁺ ions from water/wastewaters.

In this review, different ZnO-based nanocomposites were reviewed for their application in the removal of Pb²⁺ ions from the aqueous solution, typically for wastewater treatment using methodology, such as adsorption. This review focused on the ZnO-based nanocomposites for removing Pb²⁺ ions from water and wastewaters systems.

The ZnO-based nanocomposite was prepared by different methods, such as electrospinning, hydrothermal/alkali hydrothermal, direct precipitation and polymerization. Depending on the preparation method, various types of ZnO-based nanocomposites like ZnO-metal (Cu/ZnO, ZnO/ZnS, ZnO/Fe), ZnO-nonmetal (PVA/ZnO, Talc/ZnO) and ZnO-metal/nonmetal (ZnO/Na-Y zeolite) were obtained with different morphologies. The effects of operational parameters and adsorption mechanisms were discussed in the review.

The findings may be greatly useful in the application of the ZnO-based nanocomposite in the fields of organic and inorganic pollutants adsorption.

The present study is novel, because it investigated the morphological and structural properties of the synthesized ZnO-based nanocomposite using different methods and studied the capability of green-synthesized ZnO-based nanocomposite to remove Pb²⁺ ions as water contaminants.

The current review can be used for the development of environmental pollution control measures.

This paper reviews the rapidly developing field of nanocomposite technology.

The purpose of this paper is to investigate the implementation of the targeted subsidies plan in the rural and agricultural sectors of Iran and its impact on the government’s sales income, operating cash flow (OCF) and receivables collection ratio.

Using the panel data approach, the authors examine their hypotheses on a sample of six provinces of Iran, including Khorasan Razavi, Khorasan Jonoubi, Kerman, Semnan, Kermanshah and Kurdistan, during 2009-2013.

The findings indicate that the implementation of the targeted subsidies plan leads to increased actual electricity sales in the rural sector. Further, while the coefficient on OCF in the estimated model suggests a significant and positive relationship between the OCF and the implementation of the targeted subsidies plan, the coefficient on receivables collection ratio demonstrates a significant but negative association. Contrary to the government’s primary expectations, the results do not provide any support for the reduction of electricity consumption.

The current study is apparently the first study which conducted on the subject under study.

This study aims to assess the relationship between internal control weakness and different types of auditor opinions in fraudulent and non-fraudulent firms. The study's main objective is to investigate fraud in business firms and analyze internal controls and types of proposed opinions by the auditor about his desired firm. The outbreak of fraud in firms is of utmost importance to a broad spectrum of society. Internal controls and the auditor's role in preventing and detecting frauds should not be taken for granted.

The present study's statistical population includes 179 listed firms on the Stock Exchange selected as the study sample using the systematic elimination method during 2012–2019. As the study's dependent variable (the type of auditor’s opinion), research hypotheses were analyzed using the Logit regression model.

The results show that the relationship between internal control weakness and opinion type is significantly different in fraudulent and non-fraudulent firms. Moreover, the relationship between internal control weakness and type of auditor opinion in fraudulent firms and the relationship between internal control weakness and type of auditor opinion in non-fraudulent firms are significant.

By assessing the related literature, the authors have found no study to directly assess the comparative relationship between internal control weakness and the type of auditor opinion, which can be named as the main objective of the study.