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The marine and ocean energies are part of renewable energy that Wave energy converters (WECs) are used to extract them. Experimental modeling will be useful in evaluating their performance. In this research, the experimental model of an attenuator WEC is built in the Sea-Based Energy Research Group of the Babol Noshirvani University of Technology, and its performance is studied and evaluated in the wave tank of the university by applying the sea waves conditions. In this evaluation, the effects of wave amplitude and wave period on the average and maximum net power of the Wavestar system are investigated. According to the results, it was observed that in larger wave amplitudes (13 to 15), at 35 and 25 rpm, the maximum net power was close to each other and was 36.7 (Watts) and 31(Watts), respectively. Due to the irregular wave and possible damage to the system at 35 rpm, the wave amplitude of 15 and the speed of 25 rpm are chosen as the optimal mode for better performance of the system.

Climate change, in addition to increasing temperature, causes changes in the duration, intensity, form, and timing of rainfall in different parts of the Earth, which can cause droughts and floods. It also changes the volume, duration, and runoff duration, which will bring about many developments and changes in the water-resource management (Kamal and Massah Bavani, 2009). In order to reduce inconsistencies, studying the impacts of climate change on water resources is necessary. One of the most widely used models for these future studies is Atmosphere-ocean General Circulation Models (AOGCMs) (Wilby and Harris, 2006). In general, most studies present a high degree of uncertainty as a result of using AOGCMs in the simulation of climate change and hydrology parameters. the outputs of simulated water-resource models under climate change could be relied on when the uncertainties are taken into account at all stages (Semenov and Stratonovitch, 2010). In order to innovate the research method, in this study 10 AOGCMs under three greenhouse gas emission scenarios (A1B, A2, and B1) were used in the simulated range of hydro-climatic variables through climatic models and downscaling methods in the Dez Oliya basin during 2040-2069. In Summary, when reviewing the range of hydro-climatic variable changes in the future period, it could be observed that the uncertainty of AOGCMs under all three emission scenarios is greater than the downscaling methods.

These days, most of the marine structures which are constructed and used in Persian Gulf, are made of ST37 steel. Due to oil and gas sources excavated, the number of these structures is constantly increasing. On the other hand, these types of structures are exposed to corrosive environments and it is seriously critical for these structures to be used for many years. Coal tar epoxy (trade name), one of the popular coating layers, is used in different parts of steel constructions which are in use in the Persian Gulf. Several works have been carried out on the functioning quality of this coating in tidal zones, under splashing water and atmospheric conditions, but up to now no report is made in submerge zone. Hence in this investigation, three coating systems have been considered that coal tar epoxy is being used in each of one of the three layers of primer, middle and top. Two systems of laboratory and in field have been investigated for 6 months and an isolated system in field type has been also investigated. All the mechanical and chemical tests which have been performed are according to NACERPO176-64 standard which is for investigating the function of all marine coatings. All corrosion tests have been performed in Refinary Laboratory of Petroleum Industry and all the fields samples have been investigated in Steel Harbor located in the south of Bandar Abbas every week during 6 months. The test results have indicated that the coal tar epoxy which were being used in the last layer is not suitable for submerge zone. By preparing, however, a suitable surface in the first layer using zinc ethyl silicate and the last layer with antifouling, the coal tar epoxy can function properly in the middle layer.

Introduction: Safety in construction needs not only operating the executive laws and instructions but also the safety culture of all the workers in workshops. Safety culture is a factor by which all the workers are committed to having a positive share in the safety of their coworkers and themselves. Therefore, the aim of this study is identification of safety culture factors and ranking occupations in jobsites in order to improve the safety condition and promote the safety culture of high-rise projects. Material and Method: In this descriptive-analytical study, first, safety culture criteria in construction projects are identified by a literature review. Then, 8 factors of safety culture are weighted using fuzzy analytic hierarchy process. Finally, 10 different occupations in high-rise workshops are ranked from the point of view of safety culture using fuzzy TOPSIS method. Result: Results of ranking the criteria show that the most important criteria are safety attitude, supervision, policy of organization and safety training. Moreover, in high-rise construction the site superintendent and supervisor occupations have the highest and laborers have the lowest safety culture. Conclusion: In this study, after evaluating different construction occupations by hybrid FTOPSIS-FAHP method, the results are compared with the results of previous researches. Here, it was found that the findings are consistent with previous studies. On the other hand, low level of safety culture of construction laborers among the investigated occupations shows weakness in safety training and attitude; hence, the factors such as more safety supervision and training must be considered in order to create a positive safety culture for the workers.

Background and Objective: Water is one of the most valuable environmental factors that has become one of the greatest challenges of human society today. The purpose of this study was to investigate the relationship between religious attitudes toward water saving in high school students in Yazd. Materials and Methods: This cross-sectional descriptive study was conducted in 2018. 600 subjects (300 girls and 300 boys) were selected by random sampling method. The data collection tool was a questionnaire on water saving tendency including 21 questions and Religious attitude questionnaire including 60 questions. The score range for the religious attitude and the tendency to save water was 60-300 and 21-105, respectively. Data were entered into SPSS18 software and analyzed using Chi-square, Pearson correlation coefficient and descriptive statistics. Results: The mean and standard deviation of the religious attitude score and the tendency to save water consumption were 180.11 ± 14.31 and 65.27 ± 10.21, respectively. The religious attitude of students with age and gender, and the tendency toward water saving with gender variables and number of family members was significant (p<0.05). Correlation between religious attitude and tendency to water saving was statistically significant (r=0.69, p=0.01) Conclusion: Considering the positive correlation between religious attitude and tendency towards water saving, efforts to strengthen religious and moral inputs related to water consumption in students can lead to the development of an optimal water consumption attitude in this influential community of a society.

"n "nBackground and Objectives: Experiments were conducted to investigate the behavior of Moving Bed Biofilm Reactor (MBBR) as a novel aerobic process for treatment of aniline synthetic wastewater as a hard biodegradable compound is commonly used in number of industrial processes. The objective of this paper is evaluation of MBBR in different conditions for treatment of aniline and determination of reaction kinetics."nMaterials and Methods: In the MBBRs, different carriers are used to maximize the active biofilm surface area in the reactors. In this study, the reactor was filled with Light Expanded Clay Aggregate (LECA) as carriers. Evaluation of the reactor efficiency was done at different retention time of 8, 24, 48 and 72 hours with an influent COD from 100 to 3500 mg/L (filling ratio of 50%). After obtaining removal efficiencies, effluent concentration of aniline was measured by adsorption spectrum and maladaptive municipal wastewater treatment plant sludge in batch conditions for confidence of aniline biodegradation and its adsorption to the sludge mass. "nResults:The maximum obtained removal efficiencies were 91% (influent COD=2000 mg/L) after 72 hours. Biodegradation of aniline in MBBR has been also approved by NMR spectrum tests. Finally experimental data has indicated that Grau second order model and Stover-Kincannon were the best models to describe substrate loading removal rate for aniline."nConclusion:biological treatment of aniline wastewater compared to other researchers methods.

Background and Objectives: The continuous increase in solid waste generation worldwide due to population growth and industrialization, calls for management strategies that integrate concerns for environmental sustainability. By quantifying environmental impacts of systems, Life Cycle Assessment (LCA) is a tool which can contribute to answering that call. The aim of this study was to evaluate environmental pollutants resulting from various treatment options including anaerobic digestion, incineration, and landfill of Municipal Solid Waste (MSW) generated daily in Tehran. Materials and Methods: First, the physical properties of the waste and consumption of inputs in the study area were determined from September to October, 2014- 2015. Then the different steps of LCA in relation to each of the subsystems were followed (with SimaPro software). Finally, the results based on the CML Baseline 2000 were presented and analyzed. Results: It was found that when the higher rate of separation and processing in any subsystems increases, the emission of environmental pollutants decreases, so that the global warming potential, acidification, eutrophication, and abiotic depletion as the most important impact categories in the subsystems of anaerobic digestion were obtained as -125935 kg CO2/day, -449 kg SO2/day, -1690 kg PO43-/day and -0.43 kg Sb/day, respectively and in incineration were obtained as -264872 kg CO2/day, -974 kg SO2/day, -3471 kg PO43-/day and -0.76 kg Sb/day, respectively, while in the landfill subsystem, they were estimated to be 74478 kg CO2/day, 362 kg SO2/day, 118 kg PO43-/day, and 0.13 kg Sb/day, respectively. Conclusion: According to the constituent processes of each of the subsystems and the results of the evaluation of exhaust emissions subsystems, it can be concluded that in an integrated system of waste management, the energy-generating systems such as anaerobic digestion and incineration should be as the first priority and the traditional subsystems such as landfill should be as the last priority.

In this paper, the governing equations of sea waves are analyzed nonlinearly and the energy extraction from the waves in the Lark and Faror islands in the Persian Gulf is determined. According to the data in the last 31 years, the waves of these two islands have the most incidence for the height of 0-0.4 m and 0.4-0.8 m corresponding for the time periodicity of 2.4-3 s and 3-3.6 s, respectively. Therefore, waves with an average period of 3 s and a height of 0.5 m are used in the design process. The Cylindrical Energy Transfer Oscillatory (CETO) mechanism is chosen and the conceptual design is carried out with an in-house FORTRAN code, in which the results are in favorable agreement with the available experimental data. Investigations show that optimum power production requires the range of 2.8 to 3.2 for the ratio of the height to the radius of the buoy. Also, it is possible to access 25 kW power for each mechanism in the optimum conditions.

Hydraulic jump is one of the important phenomena in rapidly varied flow. Due to this phenomenon the energy loss, the upstream flow velocity significantly decreases. In the present study, hydraulic jump on a new roughened bed -with half cylindrical shape bars with three heights (r) and four different longitudinal spacing (s=1D, 2D, 3D, 4D) were investigated. In total 238 experiments were performed for a range of Froude numbers from 4.6 to 7.4 on horizontal bed and two adverse slopes of 1 and 1.5 %. The results showed that the sequent depth decreases and energy loss and bed shear stress increases as the height, spacing of the rough bars, adverse slope and Froude number increased. In hydraulic jump on adverse slope of 1.5% and rough bed with half cylindrical roughness, sequent depth 36% decreases and the bed shear stress coefficient is 16 times of its corresponding values on smooth and horizontal bed. Some empirical relations for sequent depth ratio, relative energy loss and bed shear stress coefficient were introduced. Totally, the results obtained show that, rough bed with adverse slopes may be used to achieve better performance in stilling basins.

Considering that a significant portion of the share of energy consumption among consumer sectors is in the home and commercial sectors and this share is still increasing, there is a need for research in energy consumption management and evaluation of effective indicators in the building industry. Building the country is vital to optimizing energy consumption. One of the most appropriate ways to optimize fuel consumption in the building and housing sector is the implementation of zero energy buildings which is considered as the main solution in the world. In this research, after analyzing the population and statistical sample, data were collected to evaluate effective criteria and options related to energy consumption management. First, fuzzy Delphi method was used to evaluate the sub-criteria and select the main options of each. At first level the criterion is discussed and at the second level the data analysis and research model is analyzed through paired comparisons using fuzzy hierarchical analysis technique. Finally, the most important indicators and criteria are obtained using fuzzy hierarchical analysis. According to the research findings, among the energy consumption optimization management indices investigated by the FAHP method, the economic, construction and utilities indices with 0.333, 0. 201 and 0.176 have the highest management priority, respectively. Energy-efficient optimization has a zero-energy building approach.