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This study aims to carry out numerical modeling to predict aerodynamic noise radiation from four different Savonius rotor blade profile.

Incompressible unsteady reynolds-averaged navier-stokes (URANS) approach using gamma–theta turbulence model is conducted to obtain the time accurate turbulent flow field. The Ffowcs Williams and Hawkings (FW-H) acoustic analogy formulation is used for noise predictions at optimal tip speed ratio (TSR).

The mean torque and power coefficients are compared with the experimental data and acceptable agreement is observed. The total and Mono+Dipole noise graphs are presented. A discrete tonal component at low frequencies in all graphs is attributed to the blade passing frequency at the given TSR. According to the noise prediction results, Bach type rotor has the lowest level of noise emission. The effect of TSR on the noise level from the Bach rotor is investigated. A direct relation between angular velocity and the noise emission is found.

The savonius rotor is a type of vertical axis wind turbines suited for mounting in the vicinity of residential areas. Also, wind turbines wherein operation are efficient sources of tonal and broadband noises and affect the inhabitable environment adversely. Therefore, the acoustic pollution assessment is essential for the installation of wind turbines in residential areas.

This study aims to investigate the radiated noise level of four common Savonius rotor blade profiles, namely, Bach type, Benesh type, semi-elliptic and conventional. As stated above, numbers of studies exploit the URANS method coupled with the FW-H analogy to predict the aeroacoustics behavior of wind turbines. Therefore, this approach is chosen in this research to deal with the aeroacoustics and aerodynamic calculation of the flow field around the aforementioned Savonius blade profiles. The effect of optimal TSR on the emitted noise and the contribution of thickness, loading and quadrupole sources are of interest in this study.

This paper examines the Pakistani state's shift from the accommodation to exclusion of the heterodox Ahmadiyya community, a self-defined minority sect of Islam. In 1953, the Pakistani state rejected demands by a religious movement that Ahmadis be legally declared non-Muslim. In 1974 however, the same demand was accepted. This paper argues that this shift in the state's policy toward Ahmadis was contingent on the distinct political fields in which the two religious movements were embedded. Specifically, it points to conjunctures among two processes that defined state–religious movement relations: intrastate struggles for political power, and the framing strategies of religious movements vis-à-vis core symbolic issues rife in the political field. Consequently, the exclusion of Ahmadis resulted from the transformation of the political field itself, characterized by the increasing hegemony of political discourses referencing Islam, shift toward electoral politics, and the refashioning of the religious movement through positing the “Ahmadi issue” as a national question pertaining to democratic norms.

This study aims to investigate heat and mass transfer in a one-row heat exchanger. The required equations are obtained based on two-dimensional model analysis in a cell of the heat exchanger. By using finite difference approach, the obtained equations are solved to determine distribution of temperature and the efficiency of the heat exchanger in the case of partially wet surface. In this research, Lewis Number as unity and water vapor saturation as parabolic are assumed. Obtained results show that increase in thermal conductivity fin leads to decreasing thermal resistance; therefore, temperature changes in radial from center to out of fin are reduced and efficiency of fin increases.

In this regard, fin material plays a significant role in fin efficiency. Changes in airflow also result in an efficiency increase by temperature and relative humidity, and efficiency is decreased by airflow velocity increase, and these changes are almost linear. Moreover, the fins with more wet surface are more sensitive to changes in fin dimensions and air flow characteristics, and it is a result of conjugate heat transfer mechanism, in which latent heat transfer in the fins with more wet surface has a significant role.

Thermal property and geometry of the fin under wet conditions play a more important role than the fin under dry conditions. Changes in airflow result in an efficiency increase by temperature and relative humidity, and efficiency is decreased by airflow velocity increase, and these changes are almost linear. Fins with more wet surface are more sensitive to changes in fin dimensions and air flow characteristics.

Effects of the temperature of water supply and mass flow rate were considered in the study. The results had good agreement with actual data.

This paper aims to achieve an optimal design for distribution transformers considering cost and power losses. Particle swarm optimization (PSO) algorithm is used as an optimization tool for minimizing the objective functions of design procedure which are cost and electrical and iron losses.

In this paper, distribution transformer losses are considered as operating costs. Also, transformer construction cost which depends on the amount of iron and copper in the structure is assumed as its initial cost. In addition, some other important constraints such as appropriate ranges of transformer efficiency, voltage regulation, temperature rise, no-load current, and winding fill factor are investigated in the design procedure. The PSO algorithm is applied to find optimum amount of needed copper and iron for a typical distribution transformer. Moreover, transformer impedance considered as a constraint to achieve an acceptable voltage regulation in the design process.

It is shown that the proposed design procedure provides a simple and effective approach to estimate the flux and current densities for minimizing the active part cost and active power losses which means reduction in amount of transformer total owning cost (TOC).

The methodology advances a proposal for reducing distribution transformers costs using PSO algorithm. The approach considers the aforementioned constraints and TOC to minimize the active part cost and maximize the efficiency. It is demonstrated that a designed transformer will not be optimum when the transformer losses over years are not considered in design procedure. Finally, the results prove the effectiveness of the proposed procedure in designing cost-effective distribution transformers from its initial cost until its whole life.

This paper aims to determine the optimum arrangement of a reverse osmosis system in two methods of plug and concentrate recycling.

To compare the optimum conditions of these two methods, a seawater reverse osmosis system was considered to produce fresh water at a rate of 4,000 m3/d for Mahyarkala city, located in north of Iran, for a period of 20 years. Using genetic algorithms and two-objective optimization method, the reverse osmosis system was designed.

The results showed that exergy efficiency in optimum condition for concentrate recycling and plug methods was 82.6 and 92.4 per cent, respectively. The optimizations results showed that concentrate recycling method, despite a 36 per cent reduction in the initial cost and a 2 per cent increase in maintenance expenses, provides 6 per cent higher recovery and 19.7 per cent less permeate concentration than two-stage plug method.

Optimization parameters include feed water pressure, the rate of water return from the brine for concentrate recycling system, type of SW membrane, feedwater flow rate and numbers of elements in each pressure vessel (PV). These parameters were also compared to each other in terms of recovery (R) and freshwater unit production cost. In addition, the exergy of all elements was analyzed by selecting the optimal mode of each system.

Environmental issues and lack of drinking water have forced researchers to find some alternatives to wastewater treatment. Because dyes are used in a variety of industrial applications such as textile and pharmaceutical, wastewater of these factories leads to several environmental problems. Using catalysis under ultraviolet-irradiation (photocatalysis) is one of the cases that is used in wastewater treatment. The purpose of this work is the photocatalytic degradation of dye (Reactive Red 198) and pharmaceutical (tetracycline) using MIL-53(Fe) and MIL-100(Fe).

In this work, Reactive Red 198 (RR198), an anionic dye and tetracycline as a pharmaceutical are tested with two catalysts, MIL-53(Fe) and MIL-100(Fe). Catalyst synthesis method and characterization were discussed by X-ray diffraction, scanning electron microscopy and Fourier Transform Infrared analyses, and their results are described in detail.

Dye concentration varies among 15, 20, 30 and 40 mg/L for MIL-100(Fe) for which the removal percent is 97%, 94%, 89% and 58% and for MIL-53(Fe), dye concentration increases from 20 to 40, 60 and 80 mg/L, the removal percent of which is 98%, 88%, 75% and 50%. Pharmaceutical degradation by MIL-53(Fe) and MIL-100(Fe) was 75% and 80%, respectively.

Photocatalytic degradation of RR198 and tetracycline using MIL-53(Fe) and MIL-100(Fe) was not studied in detail.

Offshore structures are among the structures exposed to fire more often. Most of these structures are likely to be associated with flammable materials. In this research, some of the structures constructed on top of marine decks have been studied.

For this purpose, the upper-bound theory of plastic analysis has been used to investigate its collapse behavior. In this way, genetic algorithm has been used for application of the combination of elementary mechanisms in the classic plastic analysis problem.

The studied structures are optimized by plastic analysis theory before and after the fire and their failure modes are compared with each other. The comparison of the results indicates significant changes in the load factor value, as well as the critical collapse mode of the structure before and after the fire.

Results indicate that the combination of plastic analysis and a genetic algorithm can predict the collapse mode of the structure before and after the fire accurately.

Osteoporosis is increasingly affecting the young female adults of the Iranian population. The role of nutrition and physical activity on bone mineral content (BMC) and bone mineral density (BMD) in young female students has not been fully examined. This study aims to assess the dietary intake of several nutrients, such as calcium, phosphorus and protein; serum concentrations of vitamin D; and physical activity and their relationship with BMC and BMD in young female students.

Three-day dietary intakes of 67 female students were measured via duplicate portion sampling (DPS) method. Calcium and phosphorus content of the food samples were determined using atomic absorption spectrophotometer. Protein intake was determined by Kjeldahl method. Serum 25(OH) D concentrations were measured using enzyme-linked immunosorbent assay. Lumbar spine and femoral neck BMD were measured using dual-energy X-ray absorptiometry (DEXA).

The mean ±SD dietary intake of protein, calcium and phosphorus was 58.8 ± 16.9 g/day, 388 ± 135 mg/day and 1884 ± 682 mg/day, respectively. Significant positive correlation was found between serum vitamin 25(OH) D concentrations and BMC of lumbar spine (r = 0.28, p = 0.016) and BMD of femoral neck (r = 0.29, p = 0.016). Moreover, the authors observed a significant positive correlation between physical activity and femoral neck BMC (r = 0.26, p = 0.03) and BMD (r = 0.28, p = 0.02). This study found no significant associations between dietary intakes of protein, calcium and phosphorus and bone density measurements.

In this study, the authors measured the dietary intake of protein, calcium and phosphorus using DPS method. This study highlights the role of physical activity and serum vitamin 25(OH) D concentrations in female students’ bone health.

This paper aims to investigate the corrosion resistance of two types of coatings – one is ceria sol coating and the other is ceria sol coating modified by ZnO nanoparticles on 7075 aluminum alloy in 3.5% NaCl solution.

Aluminum alloys were dipped into ceria sol and ceria sol modified by ZnO nanoparticles separately and removed after 10 min from the solutions and dried at 110°C for 30 min and heated at 500 °C for 30 min to form the coatings. The coatings have been characterized by using field emission scanning electron microscopy (FE-SEM), electrochemical impedance spectroscopy (EIS), X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS). The EIS tests were performed in a corrosive solution of 3.5% NaCl.

The results showed that the coating of ceria sol modified by ZnO nanoparticles has higher corrosion resistance than the ceria sol coating and the bare sample. Also, the best efficiency is related to aluminum sample immersion after 1 h in NaCl corrosive solution for coating modified by ZnO nanoparticles.

In this research, the modification of ceria sol coating by ZnO nanoparticles had an effect on improving the corrosion behavior of aluminum alloy. It is also understood that modification of coatings is an effective parameter on corrosion resistance.

This paper aims to clear ambiguities regarding the definition of intellectual capital and its components in the evaluation of rehabilitation organizations.

A preliminary definition of intellectual capital and its three domains of human, relational and structural capital and separate lists of proposed components for each domain was developed based on the results of a previous study. Fourteen experts in rehabilitation, health management and management engaged in Delphi rounds to reach agreed-upon definitions. Their ideas on relevance and the measurements of each proposed component in the assessment of intellectual capital in rehabilitation organizations were gathered by a questionnaire.

Intellectual capital was defined as “The capital that emerges from the interaction of human resources’ ‘ability to think’ and to ‘create ideas’ with ‘a favorable internal and external organizational environment’ (including the managerial, social, structural, and physical environment, as well as communication between the inside and outside of the organization).” This capital is expected to gradually increase with further education, skills training and the gaining of experience by staff and managers. Also, the further development of intra-organizational structures and inter-relations with the market will empower the organization to adapt to continually changing circumstances, leading to competitive value and profit. Finally, a list of 101 proposed components was agreed upon in the evaluation of intellectual capital in rehabilitation organizations.

This paper may lead to the development of measurement tools and ultimately to planning effective programs to increase intellectual capital in rehabilitation organizations.