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Installation layout of wind turbines plays a prominent role in the design of every wind farm. Thus, the wind farm layout optimization problem is proposed to maximize the total power output with the minimum cost. In this research, Kahrizak region in Tehran province of Iran is selected as a windy region and its real wind speed data are gleaned. Three different scenarios are also considered, with various number of generations and populations for GA parameters, effective distances, and longitude and latitude distances of turbines from each other. Among these scenarios, the best result is obtained for the one in which the longitudinal distance between turbines is greater than the latitudinal distance. By observing the wind rose of Kahrizak region, it is observed that the dominant wind direction of the region is toward the east and south-east. Therefore, by increasing the longitudinal distance of the turbines from each other, the efficiency can be improved and the turbine layout becomes more realistic. In this case, the efficiency rate and normalized cost of turbines are 89.5% and 37.4, respectively, and also 56 turbines are needed. The amounts of efficiency and power output are very convenient for real wind speed data of a region. [ABSTRACT FROM AUTHOR]

In this study, an artificial neural network (ANN) model was developed for predicting the yield and life cycle environmental impacts based on energy inputs required in processing of black tea, green tea, and oolong tea in Guilan province of Iran. A life cycle assessment (LCA) approach was used to investigate the environmental impact categories of processed tea based on the cradle to gate approach, i.e., from production of input materials using raw materials to the gate of tea processing units, i.e., packaged tea. Thus, all the tea processing operations such as withering, rolling, fermentation, drying, and packaging were considered in the analysis. The initial data were obtained from tea processing units while the required data about the background system was extracted from the EcoInvent 2.2 database. LCA results indicated that diesel fuel and corrugated paper box used in drying and packaging operations, respectively, were the main hotspots. Black tea processing unit caused the highest pollution among the three processing units. Three feed-forward back-propagation ANN models based on Levenberg-Marquardt training algorithm with two hidden layers accompanied by sigmoid activation functions and a linear transfer function in output layer, were applied for three types of processed tea. The neural networks were developed based on energy equivalents of eight different input parameters (energy equivalents of fresh tea leaves, human labor, diesel fuel, electricity, adhesive, carton, corrugated paper box, and transportation) and 11 output parameters (yield, global warming, abiotic depletion, acidification, eutrophication, ozone layer depletion, human toxicity, freshwater aquatic ecotoxicity, marine aquatic ecotoxicity, terrestrial ecotoxicity, and photochemical oxidation). The results showed that the developed ANN models with R values in the range of 0.878 to 0.990 had excellent performance in predicting all the output variables based on inputs. Energy consumption for processing of green tea, oolong tea, and black tea were calculated as 58,182, 60,947, and 66,301 MJ per ton of dry tea, respectively. [ABSTRACT FROM AUTHOR]

Saffron is regarded as an important crop in Iranian agricultural economics that needs to be investigated to produce the environmentally friendlier product. In the present study, saffron production as an important agricultural production system in Iran was evaluated thoroughly from an environmental point of view. Data were collected from saffron farmers in Southern Khorasan province of the country with face-to-face questionnaire method during cropping period of 2013-2014. The system boundary was considered from the production of raw input materials to the harvested saffron. In order to identify the main hotspot during cultivation, impact categories were considered using CML methodology and cumulative exergy demand (CExD) indicator. Based on the results, chemical fertilizers N and P were the main hotspots in abiotic depletion (AD), acidification (AC), global warming (GWP), and photochemical oxidation (PO) impact categories, while diesel fuel was the main hotspot in fresh water aquatic ecotoxicity (FE), marine aquatic ecotoxicity (ME), and terrestrial ecotoxicity (TE). Direct emission from diesel fuel combustion (saffron) was the main hotspot only in human toxicity (HT). The small farms had the highest amounts of AD, AC, EP, GWP, and PO indicators in comparison with the medium and large farms. Total CExD indicator for production of 1 kg saffron was 1894.23 MJ eq. Totally, large farms (bigger than 1 ha) had better environmental performance considering all the impact categories. [ABSTRACT FROM AUTHOR]

The present work was an attempt to assess the effective moisture diffusivity, activation energy, and energy consumption of rough rice in a batch fluidized bed dryer. Drying experiments were conducted at drying air temperatures of 50, 60, and 70 °C, superficial fluidization velocities of 2.3, 2.5, and 2.8 m/s, and solids holdup of 1.32 kg. Drying kinetics showed that the whole fluidized bed drying of rough rice occurred in the falling rate period. The effective moisture diffusivity was described by an Arrhenius equation. The evaluated effective moisture diffusivity increased with drying air temperature and superficial fluidization velocity and was found to vary from 4.78 × 10 to 1.364 × 10 m/s with R higher than 0.9643. The activation energy and the pre-exponential factor of Arrhenius equation were found to be in the range of 36.59-44.31 kJ/mol and 4.71 × 10-7.15 × 10 m/s, respectively. Both maximum values of the specific energy consumption of 74.73 MJ/kg and the total energy need of 12.43 MJ were obtained at 60 °C drying air temperature and 2.8 m/s superficial fluidization velocity. Both minimum values of the specific energy consumption of 29.98 MJ/kg and the total energy need of 4.85 MJ were obtained under drying air temperature of 70 °C and superficial fluidization velocity of 2.3 m/s. [ABSTRACT FROM AUTHOR]