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... 

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... 

Due to the strategic importance of IT, there exists an undeniable need for a systematic analysis before deciding whether or not a particular IT process should be outsourced. A study that provides a systematic analysis for evaluating components of the company's IT for outsourcing may be useful to practitioners. In this research, analytic hierarchy process (AHP) is proposed as a suitable technique for analyzing information systems outsourcing decision. An IT outsourcing case is used to demonstrate the usefulness of the proposed approach. "Super Decisions" is used to implement the AHP  

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.

 

Since early classical theories presented in management, consistently the evaluation of organization as one of the methods of control and planning has been considered. Besides due to intensification of competition among organizations, it is very important to consider performance evaluation as an effective tool in this regard. In this research DEA/AHP approach has been proposed for measuring performance organizations with fractal structure. Thus regardless of other units the first DEA model for evaluation of each pair of units is used and then a matrix of pairwise comparisons is made and the Analytical Hierarchy Process (AHP) model for two-level ranking is used. Finally the mentioned model for... 

Due to the increase in size and complexity of software systems, choosing suitable software architecture is a fundamental issue. One of the most effective ways for designing and valuating software architectures is to adopt architectural styles. An architectural style is an approach for reaping the benefits of similarities that exist between various architectures. Adoption of architectural styles in the design process of a software system assures the employment of strength points of specifications that belong to each architectural style. However, selecting a suitable architectural style depends on different criteria. Therefore it makes the ... 

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... 

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... 

Nowadays, the world is full of multi criteria decision problems and all the people should make decisions in different situations. Sometimes, the result of a decision problem is so important as a wrong decision may result in a loss that cannot be compensated. Therefore a decision making tool seems as a must. On the other hand, in this era of rapid social and technological change leading to increasing life complexity, sensitivity analysis is an important issue in all decision making processes. Analytic Hierarchy Process and Analytic Network Process, as two common tools for multi criteria decision making, are widely used throughout the past decade in different fields. Designing the model 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... 

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... 

Risk management is the systematic application of management policies, procedures and processes related to risk analysis, assessment and control activities. Risk management is the process of documenting the final decisions made and identifying and applying criteria that can be used to bring risk to an acceptable level. Costs have been studied separately as less attention has been paid to the combination of these two factors. In this study, the combined effect of these two factors on projects in the first place and then on construction, operation and transfer projects has been investigated. The statistical population of the present study consists of 250 contractors and employers of... 

Considering the daily growth of industries in international market competition and the necessity of investment in related infrastructure development, determining the priority of industries in order to strengthen or support of these industries, seems as an inevitable issue, so for the purpose of making proper decisions in an optimum way, we must use scientific decision making methods. This study evaluates the priority of industries in Iran and comparison of them. Therefore, according to the international standard classification of economic activities (ISIC), two-digit and four-digit codes are specified for each industry. In addition, based on major economic indicators, the status of these... 

Traditionally, supplier selection should simultaneously take into account numerous heterogeneous criteria and then is a tedious task for the purchasing decision makers. The global supplier selection problem is more complex than domestic one and it needs more critical analysis. It becomes especially complicated when quantity discounts are considered at the same time. Under such manner, most studies often formulate such a problem as a Multi-Objective Linear Programming (MOLP) problem, and then scale it down to a Mixed Integer Programming (MIP) problem to handle the inherited multi-objectives simultaneously. However, this approach often neglects to consider scaling and subjective weighting... 

The brushless DC Limited-Angle Torque Motor (LATM) has been widely used in area of aerospace equipment, robot drives, optical scanning systems and any drive systems that require limited motion, ranging from the simple ON-OFF servo valves to the accurate tracking of a reference signal. This paper presents the optimum design procedures of a brushless direct current limited-angle torque motor. According to a request from industry, a two-pole torque motor with a toroidal armature winding was designed based on analysis of magnetic equivalent circuit of motor structure, and using selected ferromagnetic material and rare-earth permanent magnets (PM). To select the best design solution and optimize... 

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... 

Today the losses due to road accidents in Iran are very high. For this reason, it is essential to investigate the effective factors on the road accidents. Therefore, at first, there is a need to identify the solutions of reducing the accidents, their priories and finally their efficiency improvement. In this research, using Hierarchical Analysis Method, the solutions to reduce the accidents are prioritized and then In order to conduct the AHP analysis, Expert Choice software was chosen. According to research findings, the factors that lead to accidents are categorized as: Human factors, road environmental factors, vehicle, natural factors and managerial factors. The findings show that in...