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Introduction: Most Ramadan fasting studies are usually conducted over one-year periods and show the short-term effects of Ramadan fasting. There is no standard tool or questionnaire to evaluate people's fasting habits and Ramadan fasting long term effects. For the first time, we designed a study to develop and validate a questionnaire to evaluate people's fasting habits as a tool for the determination of shortterm and long-term Ramadan fasting effects. Methods: After designing the questionnaire, it was sent to 10 experts in this field for judging and commenting (content validity). The validity of the questionnaire was evaluated using the Content Validity Ratio (CVR) index> 0.62, which includes the questionnaire's essentiality, relevancy, clarity, and comprehensiveness. In order to check the questionnaire reliability, the "test-retest method" was applied among 10 individuals. Results: After multiple drafts, the questionnaire contained 16 items, categorized into "Basic information on fasting (demographic information)", and "Fasting nutritional habits" including 13 and 3 questions, respectively. The overall CVR for relevancy, clarity, and comprehensiveness of the tool were 0.92, 0.95, 0.97, and 0.95, respectively. The Pearson correlation coefficient of the test-retest stage was 0.85. Conclusions: This Ramadan fasting habits questionnaire demonstrated strong content validity and testretest reliability. It can be an appropriate instrument for the evaluation of Ramadan fasting basic information and nutritional habits in research or practice-oriented settings for the determination of short-term and long-term Ramadan fasting effects. [ABSTRACT FROM AUTHOR]

This study develops a multi-objective approach to pursue an optimal reactive power dispatch (ORPD) of power systems equipped with wind farm (WF) integrations. The preliminary control variables include shunt compensators, synchronous condensers, and under-load tap changers (ULTCs). Innovatively, reactive power provision capability of WFs, beyond their active power contributions, is scheduled besides the variables above. Seemingly, a double operating area is adopted for WF within which it injects active power towards the main grid. Concurrently, it could inject or absorb reactive power, which impacts technical metrics of the power system operation. The main purpose is then establishing a compromise between the power loss and voltage deviation minimisation and also reducing the number of ULTC tap variations and operations. To handle the multiobjective feature of the proposed model, the global criterion method is deployed. The established ORPD model represents a multi-objective non-linear mathematical problem, which is converted to a mixed-integer linear programming format. By this way, the computational burden of the problem is reduced to maintain an acceptable accuracy of the obtained results. Detailed discussions are provided to assess the performance of the proposed model. [ABSTRACT FROM AUTHOR]

In developing countries including Iran, migration from village to city is considered among the most important socio-economic and political issues. Migration, both in the origin and destination, creates various problems and difficulties such as changes in population composition, unemployment, level of wages and per capita income, the incidence of multiple disorders caused by pressure on the limited resources of urban communities and evacuation and destruction of villages. Today, one of the government’s main concerns is to control the irregular migration, solve the city’s problems and reduce the adverse effects of migration in rural areas. If this problem is not fundamentally addressed, irregular migrations will turn into uncontrollable economic, social and political crises of society. Since the phenomenon of migration makes multiple negative effects on the origin (village) and destination (city), the ultimate goal of all rural planning is to preserve population in the environment of villages, and any study helping to maintain population in villages and reduce the migration process is important and its implementation is necessary. The present study seeks to identify the most effective factors in migration incentives of villagers in the region under investigation. Thus, the main purpose of this research is to evaluate the impact of unemployment on migration. In the present study, field work and document study were used for data collection. To this end, 10 sample villages were selected and questionnaires were distributed and completed among these villages. The reliability and validity and the number of questionnaires were calculated by Cochran formula, and Cronbach's alpha coefficient. The obtained results demonstrated that unemployment has a great effect (a high impact is relative; we should say the greatest impact) on the migration of villagers in the studied region. Hence, it is essential to make a decisive decision in relation to identifying the factors affecting the migration of villagers and suggest practical solutions to control this migration. [ABSTRACT FROM AUTHOR]

The development of industrial areas in villages can have many positive socio-economic effects. Results of studies indicate an improvement in the living conditions of villagers after the establishment of industrial areas in villages. Establishment of industrial estates in different provinces of the country has been followed by numerous environmental, economic, social, and physical effects on the region, especially the rural community. Thus, the present study seeks to do a case study concerning the effects of Binaloud Industrial Estate on the sustainability of rural settlements in Ahmadabad district of Mashhad city while considering the place and importance of industrial estates in rural areas. This research is an applied study in terms of purpose, whose results can be used in planning. For measuring the effects of industrial estates, three economic, social and environmental dimensions have been taken into account, which have been evaluated by multiple questions in the questionnaire. Thus, of 58 villages existing in Ahmadabad district of Mashhad city where Binaloud Industrial Estate has been located (research statistical population), 42 villages were selected. To determine the number of sample villages, demographic factor (villages with more than 100 inhabitants) was used. Then, considering the factor of distance dimension and access to Binaloud Industrial Estate, 10 villages were selected out of 42 villages and were used as the population of the research sample. Based on Cochran formula, unlimited population size is used to determine the sample size. Accordingly, the sample size was obtained to be 279. The sample size of each village has been calculated with regard to the proportion of the size of households in each village. In order to compare the average of respondents' opinions regarding the effect of industrial estates on the sustainability of rural settlements, comparison of the average of this variable (including three economic, social and environmental dimensions) was done with the aid of t-test with number 3 (medium), whose results indicated that p-value divided by 2 of this test is lower than 0.05 and t-statistic is positive (16.732). Hence, it can be concluded that the creation of industrial estates is effective in the sustainability of rural settlements; that is, the research hypothesis is approved with 95% confidence. Ultimately, the impact of the industrial estate on the studied villages is greater in the social and economic dimensions, and in the environmental dimension, the industrial estate has had a significant impact on only 3 villages (Avareshk, Seidabad and Fakhr Davoud). [ABSTRACT FROM AUTHOR]

This paper empirically examines the hydrodynamic performances of squat submarines under the resistance and wave tests beside numerical investigation of pressure drag reduction techniques. Despite vast information about the operation of the streamlined fluid vessels, there is not much information about the geometries and hydrodynamic behaviors of squat vessels with L/D ratios below four. This study experimentally investigates the impacts of various relative depths and flow inclinations, intending to find drag, heave, and sway forces at the velocities of 0.5, 1.0, 1.5, 2.0, and 2.5-m/s. A one-tenth scaled model of a squat submarine is examined under the resistance and wave train scenarios as the captive model in the towing tank experiments via 110 unique testing scenarios. Then, different pressure drag reduction techniques on the full-scale submarine are evaluated numerically at one-phase fluid by developing stern geometric optimization, nose rod devices, water corridors, and surface patterns at the bow and stern. Results present drag forces increase up to 150% at the 0.5D level for the resistance and wave tests due to the influences of the free surface water. The drag coefficients at the fully submerged depth of 6D differ by up to 13.3% between the numerical and experimental evaluations. • The effects of the surface water create a critical zone on the 0.5D depth level. • The drag and heave forces decrease on the surface depth level. • The heave force variations generally show a higher reduction rate. • The output trends of the wave train tests are similar to the resistance tests. • The passive pressure drag reductions are functional for submarine. [ABSTRACT FROM AUTHOR]