Sharif Digital Repository

Cognitive radio is a tool for optimal use of radio spectrum, not used by the primary users all the time. Two main features of a cognitive radio are cognitive capability and reconfigurability. An intelligent cognitive radio uses its cognition ability to identify the environmental parameters and makes future decisions based on this information. Then the reconfigurability is used to set the sending parameters to the calculated values in the cognition phase. Cogition phase consists of major steps; spectrum sensing, decision, mobility and handoff. Throughout this thesis we first propose a cooperative sensing scheme using algorithmic techniques based on sensors’ spatial information through... 

One of the most important matters beside the shortage and requirement of water in big cities is how to dispose of wastewater. Also concerns with the continued use of centralized facilities include the capacity limitation, increased population growth, sustainable use of water, water shortages due to changes in global cycles and homeland security and disaster mitigation. Therefore the use of decentralized and satellite treatment systems is essential for big cities such as Tehran. One important matter pertaining to this issue is site selection of decentralized wastewater treatment plant. Multicriteria decision making is one of the methods that is used for site selection. By multicriteria... 

The Iran-China 25-year Cooperation Program on the further economic development particularly energy area signed on 27 March 2021 by Iran, which suffered from many years of political and economic isolation and China, the second global economy. Energy transition is an essential issue in both country's energy systems which calls for a medium energy carrier that will be the natural gas. China is seeking for new natural gas resources in order to achieve its ambitious net-zero goals and Iran has targeted 50% reduction in its energy intensity. The necessity of supplying the natural gas for Pakistan and China through the CPEC (China-Pakistan Economic Corridor) by Iran is an important criterion in the... 

The use of clean energy sources has become increasingly popular around the world in recent years. One of the most important of these sources is wind energy. Due to the high wind potential in offshore areas than on land, this study uses the integration of multi-criteria decision-making methods and GIS to identify the best areas for developing offshore wind farms in the Persian Gulf and the Sea of Oman. Criteria applied in this study are divided into two categories: restrictive criteria, such as recommended transportation routes and anchored restricted areas, and technical criteria, such as wind speed and water depth. After removing the inappropriate areas using restrictive criteria, the... 

Sustainable agricultural development in the country without regard to water supply problems in terms of time and place is not possible. Construction of water storage tanks filled with water and seasonal use in dry seasons in the effective action in the optimal use of water in the climate of (low and irregular rainfall) is. The most important step in the construction of water storage tanks to choose the best point for the construction of the reservoir basin in order to reduce costs and increase efficiency. Chndmyarh different methods to decide the best option for finding a few options from there. Among these methods can be Tapsys two methods (TOPSIS) and hierarchical analysis (AHP) pointed... 

Public projects are those projects that are run by public financial resources such as tax or other national governmental incomes. Selection of these projects is relatively difficult due to their importance, long life-time, and high costs. In most models developed in previous studies to select public projects, financial matters and risks are the only factors which were considered. However, the public projects should naturally be selected in a way that citizens’ benefits are maximized (in both short- and long-term) and citizens’ living level increases. In other words, public projects should be selected to increase citizens’ satisfaction. In this thesis, a model for public projects is presented... 

In this research, the aim is to find the factors that can influence on the utility perception of both private buyers and experts. What's more, the share of each factor on the overall utility is derived by the use of AHP technique. The next step is to derive a model that contain all the factors seen by private and inexpert buyers., and their relative weight. At the next step, the aime is to complete the model by adding the factors not seen by all private buyers, but advised by residential apartment experts and their relative weight. The model should be able to rank different residential apartments, when the value of each factor is given for each ot the apartments.

 

This study aims to investigate the cost and time uncertainty of the seismic repair process of structural elements in earthquake damaged buildings in Iran. In order to identify the most important type of structural system in the country, using the method of analytic hierarchy process (AHP), 39 activists in the field of construction were interviewed. Based on the results, in buildings with reinforced concrete materials, concrete moment frames and in buildings with steel materials, steel moment frames and braced steel braced frames are the most important structural systems. By selecting the structural component of lateral load-bearing in each of the mentioned structural systems and considering... 

Analytic hierarchy process (AHP) is a structured technique for organizing and analyzing complex decision. This process is used around the world in a wide variety of decision situation, in fields such as government, business, industry, healthcare, and education. In this method, decision problem first is decomposed into a hierarchy of more easily comprehended sub-problems, each of which can be analyzed independently. Once the hierarchy is built, the decision makers systematically evaluate its various elements by comparing them to one another two at a time, with respect to their impact on an element above them in the hierarchy. In this thesis we will study the hierarchy process and also study a... 

To reduce construction costs selecting the optimal route for water conveyance line entails ample observation and considering all effective parameters. Some part of Aidoghmoush dam project of water conveyance line located in Azerbijan the east has been investigated in this research. First, by investigating, effective factors in determining the optimal route have been identified and then categorized into two groups of quantitative criteria(technical-economical) and qualitative criteria(environmental). Quantitative objectives include: slope, transportation system, infrastructures, fault and soil type. Qualitative objectives include: environmental considerations, land use and land cover. Because... 

Rewarding system is one of the most important and basic subsystem of human resources and it is one of the main concerns of the managers in any organization, since an appropriate bonus payment system increases motivation and efficiency of individuals and vice versa an inappropriate rewarding system provokes frustration in staff .Rewarding system is more important in project-oriented organizations because the most influential factor in the success and profitability of the organizations is motivated employees. The basic question in this study is that what kind of payment reward a project-oriented organization should have in order to get its employees motivation and ultimately make the... 

Green project management involves a set of management actions to identify and evaluate the effect of activities on the environment along with controlling and improving performance.Accordingly, the concepts of lean, agility, and resilience have a special place as driving forces since they can play an important role in improving the environment. Thus, this study aimed to identify and prioritize the activities related to green project management considering the concepts of lean, agility, and resilience. The present study identified the dimensions of lean, agility, and resilience for the first time in green project management.Then, this study evaluated the prioritization of activities in terms... 

Road accidents are unfortunate events that cause more thanl16000 deaths each year in Iran. Intercity accidents require a comprehensive plan to reduce casualties because the number of roads users are increasing and the accidents account for nearlyl65% of fatalities. In this study, we first tried to identify the status of Iran through a study of traffic accidents in the world, and then the research and activities carried out in Iran were analyzed to find new and effective solutions. Using the daily fatalities data froml2008 tol2014, and using the new methodology presented in this research based on the Discrete Fourier Transformation (DFT), the Box-Jenkins models and the Secant method, the... 

Iran has the second largest natural gas resources in the world and these rich resources provide Iran with good potential for exporting natural gas but so far this potential has not been used well. In contrast, India is a major importer of these energy carriers due to high energy consumption and low level of energy production, especially oil and natural gas production, and continues to increase its imports so that its natural gas imports in 2018 equals 30 billion cubic meters, the IEA expects to reach 85 billion cubic meters by 2040. So the two countries can complement each other in the field of natural gas, such as crude oil and have close relations.In this study, using AHP, Iran's gas... 

Increasing water consumption via competitive demands has resulted in serious water conflicts and the subsequent environmental crisis in river basins. The combined effects of climate change on river flow and growing water demand due to population growth, industrial and agricultural developments cause an increase of water scarcity in many basins. This is one of the drivers of both noncompliance with water allocation agreements and conflicts over the property rights to river water. Conflicts often arise when different water users compete for a limited water supply. Thus an integrated, sustainable, efficient and fair water allocation considering changes in water resources due to climate change... 

In this research various treatment methods of produce water are discussed and categorized in two groups namely; Basic and advance methods. Four basic treatment methods including; hydro cyclone, flotation, settling and membrane filtration and also four advance treatment methods including; nano filtration, ultra filtration, oxidation and adsorption are considered to compare and to select the most proper ones. To compare the treatment methods a multi criteria decision method namely Analytical Hierarchy Process (AHP) is applied twice to choose the most proper basic and advance treatment methods. The criteria are suggested according to the local conditions of Kharg Island and the similar... 

Since the start of Covid-19 pandemic lately in 2019 from Wuhan in China, a lot of countries encountered it. Healthcare sysytems are the most important system against pandemics so it is needed to measure the efficiency of healthcare systems against Covid-19 in order to find best practices. In this research, a 3-phased method is proposed to evaluate the performance of the healthcare systems. In the first phase, countries are clustered, in the second phase the DEA model is applied in 2 separate parts, in one part with considering clusters and in another without it. In the third phase resilience is introduced for Covid-19 and then it is used as a criterion beside two other criteria, DEA result... 

Airports are one of the most important elements of the aviation system that provide the ground infrastructure that is required for enabling or flight across the globe. Master Planning is currently the dominant approach to airport strategic planning. However, history shows that this approach can often result in costly mistakes. Because there are many stakeholders with conflicting objectives, deep uncertainty about the future, and many potential strategies, planners often narrow their scope by using a single forecast for the future, leaving out alternative strategies, and excluding stakeholders, resulting in a Master Plan that quickly becomes obsolete and may be opposed by some stakeholders.... 

Regarding the reduction of high qualified and accessible resources, the waste water treatments are accounted as one of the main challenges in environmental context. Surprisingly, with or without consideration of this issue can lead to play the crucial key in whether development or society retardation. With developing and being more sophisticated of waste water treatment technology and also rising the stringency of environmental constraint, approaching the optimum technology basis economics of scale is time consuming and complicated.Behind this concept, contribution of this study is twofold. The general approach of treatment is identified using AHP methodology in primary stage. After that, it... 

In plant-wide systems, faults can easily propagate due to the interconnection of streams. The main objective of this paper is to develop a systematic framework for online decision support system (DSS) in order to make the right decision to get the process out of critical conditions (which cannot be handled by the plant controllers) smoothly. One of the key features of the proposed approach is its lack of dependence on prior knowledge of the fault signals (e.g. number of faults, and their origin). In the proposed scheme, the plant is modeled by a fuzzy directed graph (FDG). The proposed scheme utilizes a backward reasoning based on the deviations that exists in the process variables...