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Introduction:Undoubtedly, the discussion of sustainability and sustainable development, regardless of cities and urbanization, will be meaningless. Cities are considered as the main cause of instability in the world because the characteristic of our age is urbanization, increasing the population of cities and consequently the development of small and large cities. During the period 1990 to 2030, the population of urban areas will grow to about 3.3 billion people, of which 90% will be in urban areas of developed countries. Attracts urban planners to the concept of sustainable urban development, the reality of rapid urbanization growth in the world today and its continuation in the future on the one hand and the amazing growth of metropolises especially in southern countries and its harmful consequences for the inhabitants of these areas. is. The concept of sustainable development has been used in various ways in various forms, but the most central idea is the World Commission on Development and Environment, which was stated in 1987, according to this definition, is sustainable development. To be able to meet the needs of the present generation without sacrificing the ability of future generations to estimate their needs. In Iran, the process of rapid development without planning and considerations of urban centers; By sharing resources, it destroys the marginal lands, gardens, forests, creating incompatible uses, and finally, water, air, soil, etc. pollution on a large scale on the face of urban environments. It can be seen that it has upset the balance of natural ecosystems. The metropolis of Isfahan has been selected as the scope of the present study; Based on statistics and information available in various fields affecting urban sustainability, it has a considerable distance from global standards. On the one hand, the increase in population (more than 8 times) during the years 1335-1395 during recent decades, along with the natural increase in population has caused this city with numerous social, physical, environmental and housing problems. , Transportation, etc., on the other hand, inappropriate use and over-capacity of natural resources, change and destruction of natural ecosystems, land use change and the creation of unequal urban spaces in the city, environmental pollution Inadequate wastewater disposal, lack of interaction between different sub-sectors of transportation, low level of services, high population density and also insecurity, the existence of which can be considered as an important factor in urban development, this city with It faces serious challenges related to sustainable urban development.Research Methods: This research is applied in terms of the purpose of the research and in terms of the nature of the methodology is based on descriptive-analytical research and based on library studies and field studies. The method of data collection is a questionnaire that 375 people were randomly selected by purposive sampling method. In order to achieve the research objectives, 16 indicators include (third place, accessibility, invitability, dynamism and vitality, comfort and security, flexibility, performance, form, meaning and content, social sustainability, social security, Social interaction, social justice, social participation, social belonging and social identity) were extracted. One-sample t-test, Pearson correlation, and Friedman test were used to discover the pattern trend to classify stability indices and the role of third places on them. The geographical area of this study includes all 15 regions. Is a city of Isfahan, which was selected to represent the entire city of District 8 in the north of Isfahan, District 9 in the west, District 3 in the center and historical context, District 4 in the east and District 6 in the south of Isfahan.Findings and Discussion: Multiple sample t-test is used to determine the status of sustainability indicators. Multiple regression analysis is used to study the simultaneous effect of the eight components of the independent variable (third places) on the dependent variable (social stability). Is. For this purpose, first the social stability variable as a dependent variable and the eight components of third urban places (accessibility and permeability, inviting, dynamism and vitality, comfort and security, flexibility and functionality, function and structure, form and meaning And content) are entered as independent variables and studied by stepwise method. In order to evaluate the status of the dynamics and vitality component of urban third places, one-sample t-test was used. This test is one of the simplest types of t-tests that is used to determine whether the average observed in a random sample is equal to the assumed population average or not. In order to investigate the relationship between the quality variables of the third urban place (form, function and meaning and content) and the identification of urban spaces in Isfahan, Pearson correlation coefficient test was used to compare the situation of social stability in different urban areas of Isfahan. One-way analysis of variance was used and finally, in order to investigate the spatial correlation between effects (selected indicators) through the Weights Manager box, a set of tools available in Geoda software, weight and coefficient in the pattern process were obtained.Results: Status of 16 indicators of sustainability of third places; Selected areas in Isfahan are in a relatively good condition. Also, the distribution of macro-indices in the third places as output values through the Moran I global index for this study were clustered in each index, respectively, and had a positive spatial autocorrelation (centralized pattern) so that Among different urban areas, the highest rate of social stability in the third places is related to urban areas 3 and 4 with averages of 89.09 and 87.61, respectively, and the lowest level of social stability is related to urban areas 6 and 8 with average, respectively. The dates were 83/20 and 83/42.

This paper develops a dynamic general equilibrium model (DGEMI) for evaluating energy policies in Iran’s economy. DGEMI provides a detailed multisector framework for analyzing economic transition, removal of energy subsidy, and technological change policies. The results show that eliminating energy subsidies (once- for -all or gradually) in the absence of technological progress is in itself insufficient to stimulate the investment and economic growth. Although the energy intensity along with this policy declines over time, its decline can not be attributed to the energy efficiency, since the economy falls into the lower level of new steady state after removing the energy subsidies. On the other hand, the combination of eliminating energy subsidies and technological progress policies provide a strong growth stimulus accompanied by a pronounced increase in productive efficiency and a decline in intensive energy.

Climate prediction demonstrates that the earth temperature has increased due to increases in concentrations of greenhouse gases. So that led to significant changes in meteorological elements. In this research the effect of climate change on rainfall and temperature at stations of Gorganrood-Gharesoo watershed for the period of 1987-2008 were examined. Daily data output by HadCM3 and ECHAM4 under scenarios of climate models using LARS-WG were downscaling and predicted for the period of 2030-2011. The results showed that based on HadCM3, the amount of rainfall 12.6, 3.3 and 3.5% and temperatures as 0.5, 0.3 and 0.31 °C respectively in the scenarios A2, B1 and A1B increased compared to the base period. Moreover, ECHAM4 model shows increases in temperature in all three scenarios. However rainfall by -11.6% under scenario B1 decreased. The results of this research could be used in water resources management planning and agriculture sector.

Abstract Background and Aim: Increasing energy consumption has created an energy crisis in the world. Fossil fuels are limited and depleting. Biogas is considered a fuel that has attracted the attention of researchers. To increase biogas production, different pretreatments have been utilized. The purpose of this study was to investigate the optimal mixing ratio of Municipal Solid Waste (MSW) and Sewage Sludge (SS), as well as the effects of various conditions of alkaline pretreatment on biodegradability of wastes and the amount of biomethane production. Materials and Methods: This study was done in a laboratory digester with 1 L volume at 37 °C with different concentrations of NaOH in a completely randomized design. Biogas volume, methane volume, and changes in pH were measured daily. Measurement parameters in the anaerobic digestion including total solids, volatile solids, and carbon and nitrogen content in the feedstock were determined according to the APHA standard methods. Results: The optimal mixing ratio of MSW to SS was 60:40 with the highest methane yield of 254.87 mL/g VS. Next, the effects of 2, 6, and 10% NaOH concentrations were evaluated on the amount of gas produced, indicating that 6% NaOH concentration significantly improved waste decomposition. Methane production, VS, and TS removal were compared to the control treatment, and there were increases of 30, 27.94, and 27.25%, respectively. Conclusion:The results showed that the mixing ratio of MSW to SS at 60:40 with 6% NaOH improves the decomposition of organic wastes and increases biomethane production. Keywords: Alkaline Pretreatment; Anaerobic Digestion; Biogas; Municipal Solid Waste; Sewage Sludge

While the fibers in concrete cause soft rupture, the compressive and tensile samples are not ruptured after failure. This is one of the benefits of metallic fibers, especially the sinusoidal and hooked fibers: using these gives residents the opportunity to escape during an earthquake. In addition to positively impacting mechanical properties, metal fibers improve the matrix of concrete, provide ductility and response to impact load, and control crack width and propagation. Fly ash and micro-silica improve the durability and performance of concrete and are effective in protecting the environment: they can, thus, be used to replace cement. In this study, the samples’ compressive and tensile strength was prepared: they were of non-fibrous concrete and concrete containing steel fibers with 6 different percentages (0.4, 0.6, 0.8, 1, 1.2, 1.5). They were also composed of metallic fiber and polypropylene in three different compositions (0.3PP + 0.8SF, 0.4PP + 0.4SF, and 0.15PP + 1.5SF). These were investigated: seismic parameters were extracted after achieving the optimal percentage (the percentage with the highest compressive and tensile strength given economic considerations) under the loading protocol SAC/BD 97.02. This allowed investigation of the curves of hysteresis, energy absorption, lateral displacement, and effects of the use of these fibers. The major properties of pozzolanic materials were considered in the last step of this research: fly ash and microsilica were added to concrete containing metal fibers with the optimum percentage of metallic fibers. These were compared with concrete containing metallic fibers and non-fiber concrete. Thereafter, the appropriate percentage of cement replacement was determined so as to better understand the effect of the use of fly ash and microsilica in preventing the buckling of buckling restrained braces.

A huge part of the thermal energy consumed in energy industries is lost after exiting the process. Some of this waste heat can be recovered by various methods such as generating electrical energy, generating hot air for the production process or providing hot water. In Iran, the cement industry has always been far from the optimal use of resources, including energy, due to the existence of energy subsidies. In this research, the heat loss from the baking system of Nireez white cement plant as a model industry of the country to evaluate the simultaneous production of heat and electricity by using the organic Rankine cycle that generates electric power has been investigated in Span Plus V12 software. This evaluation is done to calculate the heat loss, including the mass and energy balance on the cooking system, as well as the energy balance on the pre-cooking system. The heat energy obtained enters the Rankine cycle and is converted into energy by the turbine. The results show that 635 kilowatts of electrical energy was produced from energy recycling, which leads to the elimination of 317.5 kg/hour of greenhouse gas.

National Iranian Oil Company as the second largest oil company in the world and the biggest business complex of Iran has an undeniable importance in Iran, and its activities and management have significant impact on economic and political spheres of the country. The issue of reforming the NIOC articles of association has been a matter of discussion for years in the legislative and administration departments. The stated reasons could be the separation of state duties from the company duties, defining company’s scope of work, omission of additional advantages and adjustment with the new upstream legislations. This study is an attempt to answer the question of “what are the features and principles of a desirable NIOC articles of association?” This question is dealt with by analyzing the past NIOC articles of association as well as examining the selected similar articles of association from National Oil Companies world-wide. Based on this analysis, the acts such as concentration of NIOC on company duties and administrative affairs, not being involved in government affairs and subsequently submission of all the responsibilities and authorizations related to conservation, controlling and supervision on upstream activities to The Ministry of Petroleum are suggested to the National Iranian Oil Company. Considering the professional and business essence of NIOC responsibilities, the activities of the company must be performed in a competitive context with no specific exclusive advantage. More specifically, NIOC can succeed in a competitive environment only under the circumstances of facing the risks inherent in its activities.

Introduction: Osteoarthritis is one of the most common musculoskeletal disorders. Analyzing the energy expenditure in people who suffer from musculoskeletal disorders provides objective evidence to measure individual’s disability and the effect of therapeutic interventions. Present study investigated the effect of various severities of knee osteoarthritis on mechanical energy of lower extremities. Materials and Methods: 48 women aged between 40-70 years were purposefully divided into mild, moderate and sever osteoarthritis and healthy control group according to simple X-ray features of their knee joints. The participants walked at their convenient self-selected speed to collect five clean trials. The data were recorded using a motion analysis system and a 3-dimentional model of lower extremity segments was developed from motion capture data using visual 3-D software. Mechanical energy of lower extremity was calculated using this model. Results: The study groups were significantly different in age (P ≤ 0.001) and walking speed (P ≤ 0.001). One-way analysis of variances (ANOVA) and post-hoc Tukey test revealed that there was significant difference between the study groups regarding mechanical energy. However, univariate general linear models with adjustments to age and to walking speed were developed; in addition, a bivariate general linear model was adjusted to age and walking speed. All the models confirmed that the differences were not imposed by the severity of knee osteoarthritis. Conclusion: It seems that increase in mechanical energy of lower extremity in subjects with knee osteoarthritis intensifies with the progression of the disease; this is not a direct effect of the level of joint deterioration but is an indirect effect of older age and lower walking speed in subjects suffering from more advanced knee osteoarthritis.

Today, electron therapy has a lot of advantages such as: its homogenous, dose in the target volume, low absorbed dose for the normal tissues, non-effective transmitted dose of air bubble which surrounded the target (in comparison of photon treatments), controllability in turning on and electron beam flux adjustment during the treatment. It has no interchangeable case in the most treatment centers. Electron can use for up to 20cm depth in radiation therapies. In this study, we demonstrate, for the first time, a design of flexible guider for the electron accelerator output, which may increase the treatment ability effectively. One of the important of its advantages is non-limited ability in treatment of tumors in case of deep depth, in other words overcome to limitation of surface cancer treatment and providing a safe condition for other normal tissues during the radiation therapy. One of the important of its advantages is non-limited ability in treatment of tumors in case of deep depth, in other words overcome to limitation of surface cancer treatment and providing a safe condition for other normal tissues during the radiation therapy. in other words overcome to limitation of surface cancer treatment and providing a safe condition for other normal tissues during the radiation therapy.

Iran as a developing country possesses rich and extensive energy resources has an advantage in energy-intensive industries. In this research, Granger-causal relationship between economic growth in Iran and various energy carriers including oil products, electricity, natural gas and solid fuels are investigated using Toda and Yamamoto procedure for period 1967-2002. The results reveal that there is a unidirectional Granger-causal relationship from electricity consumption and oil products consumption to economic growth. Likewise, there is a unidirectional Granger-causal relationship from economic growth to solid fuels consumption and natural gas consumption. Estimation of error correction models reveal that in the short run and long run, there is bidirectional Granger-causality between electricity consumption and economic growth. Likewise, in the long run, a unidirectional Granger-causality runs from economic growth to natural gas consumption. Therefore, in the cases that unidirectional Granger-causality runs from energy consumption to economic growth, energy conservation policies should be designed carefully in a way that utilization of such policies doesn't have diminishing effects on economic growth. Accordingly, we suggest a set of “optimal usage” and “efficient consumption” policies in economic sectors. In the cases that unidirectional Granger-causality runs from economic growth to energy consumption, energy conservation policies could be implemented without impeding economic growth.