Sharif Digital Repository

Tehran is surrounded by about ten active faults, which have had no major seismic activity during the last 200 years. Considering soil characteristics, the faults may cause fault ruptures, resonance, landslides in some areas. Tehran's MPE is determined to be about 0.4g which is a high seismic hazard. Specific codes have been generated in the last 50 years to ensure structures' stability when a quake occurs, but observations show that the codes are not fully implemented in the construction of public structures in Tehran. In this study, first the structural imperfections observed in the public structures and their effect on the structures' seismic performance were reviewed. The imperfections... 

In a macro view point, it can be said that housing demand in recent years is making the construction industry one of the main sectors of Iran’s economy. On the other hand, analysis of seismic risk in the country with regard to the geological conditions, the faults, and the seismic records of mega city of Tehran is depicting the delicate location of the Iranian capital. This city is selected as a case study in this thesis that has a high probability for the event; where this event has also been classified as a devastating earthquake ever. Due to the involvement of private sector in construction industry, the need for establishing a system of strict control on quality of construction of the... 

Forecasting model of water consumption amounts could be used in order to manage water resources for future condition of city. In this thesis, a model for forecasting water demand for Tehran has been presented by evaluating regression models and intelligent models. In this study, uncertainties which are connected to climate and population changes are taken into account. The considered variables include minimum, maximum and medium temperature, precipitation and solar radiation. Considering objectives of this thesis and various forecasting methods and their advantages and regional conditions of Tehran, in addition to regression analysis, perceptron neural network, probabilistic neural network... 

Tehran, the capital of Iran, like many megacities in the world is encountered with increasing freshwater demand and water resources limitation because of the rapid growth of population. In spite of the existence of neighboring water recourses; such as Karaj-Dam, Latian-Dam and Lar-Dam, and large usage of groundwater, the management of urban water demand is one of the biggest problems with this city. In this thesis, water reuse and wastewater recycling are considered as a sustainable solution for water supply and wastewater management of Tehran. A linear programming optimization model with the object of cost minimization is used to allocate water between users and resources, concerning the... 

The objective of this research is to develop a mathematical model for analysis and design of airport cities. In this model, the interactions among the elements of an airport city -regarded as a complex system- will be analyzed, and the impact of the stakeholders’ requirements on the functional and physical architecture of the airport city will be investigated. So as the first step, the stakeholders of the system and their requirements are identified and classified. Second, the concept of operation of the airport city is investigated, and then the architecture of the system is modeled as a queuing network. So that each element of the airport city is regarded as a service center, including the... 

About 6.5 million people die from air pollution annually, of which 5.5 million are from the Asian continent. By considering reduction of life span and external costs associated with the emission of air pollutants, the importance of environmental impact assessment and managing the reduction of pollutant emissions becomes even more important. Meanwhile, the largest share (85%) of pollutant emissions is related to the supply and demand sectors of energy carriers. Therefore, the design and development of the environmental impact assessment system of energy flows is a necessity in the process of sustainable development of the energy sector.A key policy challenge in Tehran megacity is to curb high... 

The concentration of air pollutants in the environment is variable according to different factors, including distances from main sources. Vehicles in streets and highways are one of the most important sources of the air pollutants. Hemmat highway is one of the most significant highways in Tehran with traffic congestion of 15000 to 18000 vehicle/hour. In this research, the concentrations of PM10 and CO were determined in different distances of Shahid Hemmat highway and the relationship diagrams of traffic and meteorology to the amount and emission of air pollutants were drawn. The concentration gradient diagrams showed exponential decay, which demonstrated that more than of 50% of air... 

Due to advantages of Peer-to-Peer (P2P) networks, many internet users use them for content distribution (Many internet users distribute content using them). These systems may be categorized to Centralized, Pure, and Hybrid. Gnutella is a heavily decentralized and unstructured file sharing P2P networks that are responsible for a good part of the traffic on the internet. These P2P networks are at risk of many security threats from internet worms. Internet worms and their threats are a major concern to the networking community. In this thesis we concentrate on passive non-scanning worms and propose a novel approach to detect such worms. As part of our work, we collected data from the Gnutella... 

Business cycles have been always one of the main issues discussed in macroeconomics. Nonlinear trend is one of the main characteristics of business cycles. Linear models are not able to explain this nonlinear nature. In order to capture nonlinear features of variables such as change rate of housing price or GDP which have severe ascending and descending and nonlinear behavior, regime switching models, specially Markov regime switching model, have been replaced existing linear models. Comprised to other models, regime switching model has a main advantage: this model is able to consider two important features of business cycles, i.e. asymmetry of different stages of business cycles and... 

The citizens’ dissatisfaction with the decreased life and residential care quality is increasing as a result of the rapid growth and development of cities. To find an effective solution to reduce and control these harmful effects is one of the main concerns of urban managers and planners in most countries. In this research, various ecological and sustainability criteria were selected through library-based studies and relative recognition of the region. The Maps were mostly provided through satellite imagery and some by using synoptic data collected from the official aerology website of the country, Iran. Through surveying the experts, different criteria were evaluated and based on the...