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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.

This study aims to present a basic mathematical model for investigating the structure of counter-flow non-premixed laminar flames propagating through uniformly-distributed organic fuel particles considering preheat, drying, vaporization, reaction and oxidizer zones.

Lycopodium particles and air are taken as biofuel and oxidizer, respectively. Dimensionalized and non-dimensionalized forms of mass and energy conservation equations are derived for each zone taking into account proper boundary and jump conditions. Subsequently, to solve the governing equations, an asymptotic method is used. For validation purpose, results achieved from the present analysis are compared with reliable data reported in the literature under certain conditions.

With regard to the comparisons, although different complex non-homogeneous differential equations are solved in this paper, acceptable agreements are observed. Finally, the impacts of significant parameters including fuel and oxidizer Lewis numbers, equivalence ratio, mass particle concentration, fuel and oxidizer mass fractions and lycopodium initial temperature on the flame temperature, flame front position and flow strain rate are elaborately explained.

An asymptotic method for mathematical modeling of counter-flow non-premixed multi-zone laminar flames propagating through lycopodium particles.

Because of the appreciable application of heat recovery systems for the increment of overall efficiency of micro gas turbines, promising evaluation and optimization are crucial. This paper aims to propose a multi-factor theoretical methodology for analysis, optimization and comparison of potential plate-fin recuperators incorporated into micro gas turbines. Energetic, exergetic, economic and environmental factors are covered.

To demonstrate applicability and reliability of the methodology, detailed thermo-hydraulic analysis, sensitivity analysis and optimization are conducted on the recuperators with louver and offset-strip fins using a genetic algorithm. To assess the relationship between investment cost and profit for the recuperated systems, payback period (PBP), which incorporates all the factors is used as the universal objective function. To compare the performance of the recuperated and non-recuperated systems, exergy efficiency, exergy destruction and corresponding cost rate, fuel consumption and environmental damage cost rates, capital and operational cost rates and acquired profit rates are determined.

Based on the results, optimal PBP of the louvered-fin recuperator (147 days) is slightly lower than that with offset-strip fins (153 days). The highest profit rate is acquired by reduction of exergy destruction cost rate and corresponding decrements for louver and offset-strip fins are 2.3 and 3.9 times compared to simple cycle, respectively.

This mathematical study, for the first time, focuses on introducing a reliable methodology, which covers energetic, exergetic, economic and environmental points of view beneficial for design and selection of efficient plate-fin recuperators for micro gas turbine applications.

The widespread usage of magnetic nanoparticles (MNPs) requires their efficient synthesis during combustion process. This study aims to present a mathematical model for the oxidation of MNPs in a counter-flow non-premixed combustion system to produce MNPs, where the key sub-processes during the oxidation reaction are involved.

To accurately describe structure of flame and determine distributions of temperature and mass fractions of both reactants and products, equations of energy and mass conservations were solved based on the prevailing assumptions that three regions, i.e. preheating, reaction and oxidizer zones exist.

The numerical simulation was first validated against experimental data and characteristics of the combustion process are discussed. Eventually, the influences of crucial parameters such as reactant Lewis numbers, strain rate ratio, particle size, inert gas and thermophoretic force on structure of flame and combustion behavior were examined. The results show that maximum flame temperature can achieve 2,205 K. Replacing nitrogen with argon and helium as carrier gases can increase flame temperature by about 27% and 34%, respectively. Additionally, maximum absolute thermophoretic force was found at approximately 9.6 × 10–8 N.

To the best of authors’ knowledge, this is the first time to numerically model the preparation of MNPs in a counter-flow non-premixed combustion configuration, which can guide large-scale experimental work in a more effective way.

The purpose of this paper is to determine the food safety knowledge and practices of the Iranian consumers and also its association with socio-demographic characteristics.

In the present cross-sectional and population-based study, the validated food safety questionnaires applied to 1,500 participants who were selected through multistage stratified cluster sampling from the capital city and regional area of East-Azerbaijan – Iran. The Student t-test and analysis of variance and linear regression were used for statistical analysis.

Although the overall percentages of mean score for knowledge (77.66 percent) and self-reported practice (70.77 percent) were good, there was a low level of awareness and self-reported practice in some subsections such as optimal heating/cooling temperature, proper thawing techniques and eating raw egg. Female and married respondents had significantly higher mean knowledge score than males (p<0.001) and singles (p=0.04). Residents of regional areas acted more safely than capital city residents (p=0.01).

Despite the good knowledge of some respondents regarding food safety, their food safety practices were poor. It can thus be suggested that the future studies have better focus on investigating the perceived barriers of consumers about food safety practices.

Although the mean knowledge and practice regarding food safety of Iranian consumers was good, yet there is the lack of knowledge and practice on some important factors related to food poisonings such as eating raw or lightly cooked egg or improper heating/thawing practices. So, it is important to develop proper food safety education programs emphasizing on these issues. According to lower food safety knowledge and practice of low-educated, single and male respondents, the educational programs should mainly focus on these groups.

For the development of effective food safety education programs in Iran, learning about the basic knowledge and practice of consumers is essential; however, there is limited data that directly tackles this issue in Iran.

Clinical governance (CG) was used as a driver to improve safety and quality of healthcare. CG implementing is a change in health system and all the stakeholders must be participating. The purpose of this paper is to study nurses’ experience about CG movement in Tabriz hospitals.

A qualitative study using Focus Group Discussions (FGD) was done. Purposeful Sampling was used to select the objectives including 65 participants. Actually seven FGD’s were held. Content analysis was used to extract the meaningful themes.

It is revealed that nurses are the focal point in CG implementation in hospitals. Low commitment of managers and lack of physicians’ contribution was experienced by nurses. However, personnel education and development and patient safety have got more attention. Blame culture and increased work stress was reported as challenges.

CG as a change in healthcare system, especially in low- and middle-income countries, is faced by several challenges and its implementation would have different experiences. Nursing staff, the major group in hospitals, would be having interesting experiences through CG. Their practical opinions could guide the policy makers to employ proper plans to effectively implement CG. Considering the result of this study in practice would lead to improve CG implementation.

Clinical governance should be based on cultural elements that value lifelong learning, skill development and research. The purpose of this paper is to introduce a set of indicators to improve educational governance in hospitals.

Key indicators were identified from the international and national literatures. Later, the indicators were rated and prioritized by a multidisciplinary panel of medical professionals using two rounds of Delphi technique. Subsequently at two consensus meetings, the panel evaluated the indicators.

A set of 51 draft indicators were identified. The expert panel members rated 28 indicators as high priority indicators for measuring educational performance of the hospitals.

This set of indicators can be used to measure the educational performance of the hospitals in identifying the gaps and take steps to resolve them.

Education and training is the basic component of clinical governance. Hospital staff education and training is a fundamental step towards organizational and individual development. To improve the educational performance at hospital level it is necessary to reliably measure such performance. This can be done through developing and using relevant indicators. There are limited systematic studies, especially in middle and low income countries, to introduce appropriate indicators. This study has investigated developing a set of indicators to measure and improve the educational performance in hospitals.

The purpose of this paper is to investigate the quality of the frying oil used in restaurants, fast food establishments, and confectionary stores. The compliance of used frying oils with the quality standards as determined by the peroxide value (PV) and the total polar materials (TPMs) is investigated by analyzing 375 samples of oil.

The PV was measured according to the national standard procedure number 4179, while the TPM was determined using a Testo 270 cooking oil tester. Frying oils with a PV>5 mEq/kg and a TPM>25 percent were considered to be non-edible. For a comparison of groups, the Mann-Whitney and Spearman correlation tests were used, and p<0.05 was considered significant.

The maximum TPM and PV recorded for frying oils in fast food restaurants were 97.5 percent and 77.9 mEq/kg, respectively. The results also revealed that 60 percent of samples were non-edible according to the TPM, while 58.9 percent of the oil samples were non-edible because of the PV. TPM and PV correlated well with each other (r=0.99, p<0.001) and with oil replacement intervals (r=0.90, p<0.001). The relationship between the TPM and PV was stronger in the polynomial model than the linear model. The following equation was obtained: peroxide (mEq/kg oil)=0.0043 TPM2 (%)+0.1587 TPM (%)–0.6152.

Considering the current limitations in official supervision by health authority, on-site self-monitoring of the TPM using the Testo 270 cooking oil tester by sellers as a solution seems a new approach. Food stores, restaurants, and confectionary stores should be equipped with TPM analyzers to determine the quality of the frying oil and the timely replacement of non-edible oils.

This bibliography is offered as a practical guide to published papers, conference proceedings papers and theses/dissertations on the finite element (FE) and boundary element (BE) applications in different fields of biomechanics between 1976 and 1991. The aim of this paper is to help the users of FE and BE techniques to get better value from a large collection of papers on the subjects. Categories in biomechanics included in this survey are: orthopaedic mechanics, dental mechanics, cardiovascular mechanics, soft tissue mechanics, biological flow, impact injury, and other fields of applications. More than 900 references are listed.

The purpose of this study was to explore the potential benefits of Coriandrum sativum (C. sativum) on anxiety, depression, sleep quality and memory among students.

This randomized controlled trial involved university students aged 18–25 years, who had no known allergies to C. sativum or were using psychotropic medication. After giving informed consent, participants were randomly assigned using a computer-generated random sequence to either 500 mg C. sativum seeds or a placebo. Primary outcomes measured changes in memory (prospective and retrospective memory questionnaire [PRMQ]), anxiety and depression (Hospital Anxiety and Depression Scale), while secondary outcomes assessed sleep quality (Pittsburgh sleep quality inventory [PSQI]).

A sample of 86 students with a mean age of 20.05 ± 1.6 years was selected for the study. Initial assessments ensured no significant differences in demographic or study variables between the control and intervention groups. Statistical analysis revealed significant improvements in memory (PRMQ: p = 0.006), anxiety (Hospital Anxiety Scale: p = 0.04) and depression (Hospital Depression Scale: p = 0.002), as well as in sleep quality (PSQI: p = 0.03) in the group receiving C. sativum compared to the control group.

This research offers initial insights into the potential benefits of C. sativum intake, specifically its role in enhancing memory performance and mitigating anxiety among student populations. The results present a compelling case for further research in this domain to solidify these preliminary conclusions.