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on one hand, Iran due to the low annual rainfall and lack of appropriate spatial and temporal distribution in precipitation is considered as an arid and semi-arid country experiencing stress and water scarcity; on the other hand, 90% of annual water consumption has been allocated to agriculture sector in Iran and efficiency and productivity of water consumption do not enjoy favorable status in this sector. While it can overcome this problem by use of virtual water criterion in trade with the countries which enjoy water status such as Turkey. In this regards, the present study has examined this issue in form of selected agriculture goods based on common indices for detection of trade opportunities. Cosine criterion indicated that the degree of similarity and complementary of Turkey’s export with Iran is greater than structural similarity of Iran’s export with Turkey. With regard to trade potential calculations, Iran and Turkey have high export capacity in trade of agriculture goods. Further, Index of Drysdale indicated that the possibility for development of trade from Turkey to Iran is greater than trade from Iran to Turkey and ultimately adjustment of Balasa index based on virtual water trade process indicated that Iran should change its import and export priorities at area of agriculture products. Further, results from research indicate that applying virtual water criterion and removing the products lacking relative advantage in trade between Iran and Turkey result in increase in export of Turkey’s agricultural products to Iran and increase in Iran’s benefit in trade of virtual water.

Biology has been a brilliant teacher and a precious textbook to man-made construction for thousands of years, because it allows one to learn and be inspired by nature’s remarkable and efficient structural systems. Concepts unfortunately have this in common that in general use often specifies incorrectly some phenomena. There was a turning point in each period of time which human has discovered a new sight about the world and nature order in a way, and then has presented this relation by numeral, artful and industrial language. The relation between nature and human considers different periods. At first it was bio-utilization which degrades the value of nature as a source of energy and material. After revolution in science development and attention to the damages which they made to environment, they tried to change their look to this issue and expand the mean of relation between human and nature. Birth of such word like bio architecture emphasize on the new point of view at nature. The role of nature and importance of natural resources in human’s social-economic (and even his psychological) life is undeniable, and also it is essential to note that God is the Creator and man the explorer. This paper aims to call a close multidisciplinary collaboration that promotes engineers to build more sustainable and smart structural systems for bridges in the 21st century. In this article survey the introduction of bionic architecture and related categories.

In most countries, a major source of government revenue is funded through taxes. Tax share of total public revenues is different among countries and the rate depends on the level of development and economic structure. For this reason, the necessity to understanding of causes, aggravating factors, tax evasion, providing practical solutions and scientific recommendations will be inevitable. According to the current study by using a smooth transition regression (STR) and annual data from 1971-2015, we investigate the effects of direct financing through amendments of direct tax law on economic growth in Iran's conventional model of economic growth. The results of this study, along with the theoretical foundations and the prevailing belief of most economists, showed that the effect of different methods of financing through direct taxes on economic growth in Iran conditional on the state of the economy, in particular in accordance with the results of investment. It means that in the first regime, when the investment share of GDP is became less than 34/05 percent, financed by oil revenues has negative effects and financing through tax revenues had a positive effect on economic growth. But in the second regime, when the investment share of GDP is more than 28/01 percent, the financing of both oil and tax revenues had a positive effect on economic growth. Although in the second regime and by increasing the investment to keep pace with positive impact on the severity funded through tax revenues increased.

Investigation on modern history of urban planning in Iran shows that there are three approaches in the subject under discussion: “Modernism and Westernism”, “Traditionalism and anti-Westernism”, and “Adopt and Adapt”. Proponents of the first approach believe in encouraging methods to use the external concepts. The second, is the idea about ​​cultural and religious values, ​​thereby everything with nontraditional orientation is rejected. In the third approach the thinkers believe that if the parts of tradition are synthesized by modernity, culture and religion can adapt themselves with the development. The purpose of this study is to evaluate the adaptation of traditional urban design patterns of Islamic-Iranian cities in incompatible district of new Iranian cities (spontaneous settlements) and to focus on the application of the third approach in the current situation of Iranian cities. On this basis, the method of comparative analysis has been applied to survey the differences and similarities between historical districts and spontaneous settlements. Studies show that there are rather similarities among physical - spatial parameters (such as structural and environmental criteria) between the two types of districts; because both of these residential districts formed as organic structures that are unstable against unexpected risks and earthquake. However, there are the differences between these two types of districts in organized and formed periods. Despite historical districts that have been consolidated and organized during hundreds of years, spontaneous urban textures formed quickly and without any plan and planning. Meanwhile, the historical districts have usually integrated townscapes and unique materials such as clay, bricks or stone, while this character (integrated townscape and unique materials) never have been seen in the spontaneous settlements. There are similarities in economic and socio- cultural characteristics between residents in the two the types of districts. The residents living in poor economic condition, but under a very strong socio-capital and traditional beliefs; There can be seen several socio-cultural and particularly religious characteristics in people of historical residential districts that are similar with the spontaneous residential places, such as “strong relationship among families, friends”, “hospitality”, “mutual relationship among family members”, strong religious beliefs and the needs for privacy and security. However, these communities are different in some principles such as quality of life and spatial and physical qualities especially in favorable and beautiful urban landscapes. So it can be extracted and adopted excellent principles from traditional and historical districts and adapt them to the inappropriate modern urban districts. With regard to the existence of these similarities, we explain applicable principles of the spatial characteristics and designing quality in the historical district of Yazd to apply in Baghshater District in Tehran as a spontaneous settlement. Findings show that we can use several solutions to reconstruct this zone included: 1) land readjustment as the suitable solution in Baghshater District with regard to the familial residential pattern in historical zone of Yazd such as Fahadan District. 2) Focusing on the traditional concept of mutual relationship in residential houses. 3) Emphasizing on the hierarchy of The entrances and exits of the residential units.

Hail phenomenon is one of the hazardous weather phenomena that can make the highest amount of damage to farms, gardens, cars, rooftops, etc. in a very short time (a few minutes), depending on the diameter of the particles. One of the best ways to study this devastating climatic phenomenon is the use of atmospheric instability indices. The indices which are calculated with the help of radiosonde data give a fairly comprehensive vision regarding the occurrence of such phenomenon. In this study, the incidence of moderate to severe hail is investigated in the period of 1990-2010. First, the atmospheric codes related to hail phenomena were applied to extract the data, then radiosonde data in intended time were received and applying the RAOB software, the physical status of atmosphere was studied. In the studied period, two hail examples were reported on November 27, 2008 and December 5, 2008. In the first instance of hail that occurred on November 27, 2008, the status of some indicators was calculated and it was found that LCL was at an altitude of 284 meters, CCL at an altitude of 1582 meters, LFC at an altitude of 6230 meters, the ice surface at an altitude of 3278 meters, the LI index was -0.2, the K index was 25.7 ° C, and PWC was 28 mm. In the above mentioned conditions, there was a hail with a diameter of 25.4 mm. In the second instance of hail that occurred on December 5, 2008, the status of some indicators was calculated and the results showed that LCL was at an altitude of 280 meters, CCL at an altitude of 1762 meters, LFC at an altitude of 2271 meters, the ice surface at an altitude of 2771 meters, the LI index was -1.4, the K index was 27.1 ° C, and PWC was 23.6 mm. In the above mentioned conditions, there was a hail with a diameter of 3.6 mm. Given that in many ways, the status of most atmospheric indicators in the two above examples of hail were close to each other, it turns out that in similar circumstances, the greater the distance the ice level gets to the summit of cloud, the greater is the probability of hails larger in diameter. The value of this distance for November 27, 2008 was at approximately 6384 meters and for December 5, 2008, it was at about 5012 meters.

Today, with the development of urbanization and increased abnormal behaviors, particularly urban crimes, prevention of social harms is of great importance. Social Sciences and Urban Development can prevent crime in urban areas by understanding cultural and social traits alongside other actions, in a way that the wrongdoer finds less opportunity for acting a criminal behavior in urban areas. The theory of social capital is intrinsically simple and affecting many other components. The core idea of social capital can be found and summed up in the word "relationship". Members of the community can cooperate and work together through making contacts with each other sustaining this relation. And thus they learn things that cannot be easily achieved alone or is hard-won. Humans are linked through a series of interconnected networks and tend to have values in common with other members of the network. And by expanding networks constitute an asset that can be considered as a form of capital. Obviously, the more people get to know each other and the more common outlook is found within them, we'll have a richer social capital. On this basis, this research will examine social capital in two dimensions, cultural (types of the trust) and structural (social participation and emotional and material support of network). And tries to study the relationship between social capital and social problems in the Pardis new city after explaining the concept of social capital; This research was conducted with survey method using a questionnaire technique. The statistical populations of the study are residents of Pardis new town, who have been selected though a random cluster sampling method. The sample size was determined as 400 people using Cochran Formula and finally data analysis was done with SPSS Software. The results show that increasing social capital components (cooperation, solidarity and social relations), social problems in new towns is reduced.