Sharif Digital Repository

Increasing demand of bandwidth in wireless communications systems led to excessive congestion in frequency spectrum. Since radio spectrum is an expensive and rare source, its efcient use is an important challenge. These limitations as well as increasing number of communications service users,necessitate the use of newer technologies that work efciently with numerous users. Device-to-Device (D2D) communications, full-duplex capability and cognitive radio systems are introduced for this reason. In the previous technologies, due to excessive self-interference (SI), full-duplex transmission has not been implemented. However nowadays technology allows self-interference to be attenuated up to 100... 

Nanotechnology requires a number of infrastructures for reaching its sustainable development. For each step of its development , various infrastructures should be studied and prepared in advance.In this direction, by introducing and recognizing the priority of Iran Nanotechnology R&D indexes ,the present research is going to propose an effective help. In this case, after studying the related literature and gathering the needed data , 27 indexes were recognized. Then , the indexes were divided in 7 criteria.In order to find the priority of the applied indexes , Fuzzy Multiple Criteria Decision Making (FMCDM) was applied. As the weighting of 7 criteria had been found by FANP , the... 

The use of IoT-based technologies is expanding in many areas today. The use of audio and video processing in IoT systems has been used as an alternative to human operators by increasing power and reducing processing costs. Due to the large volume of audio and video data and bandwidth limitations, complete data transfer to cloud processing servers is not cost-effective in terms of efficiency and energy consumption. As a result, the solution that has provided good results is to discharge these device tasks to the available clouds. In other words, the capacity of resources in the environment can be used to optimize the total latency of the system and energy consumption. In this dissertation, we... 

In this project an optimized and robust orientation estimation method using IMU and magnetic sensors is presented. Magnetic distortion effects in orientation estimation is also one of the main purposes. Proposed sensor fusion algorithm is based on a complementary filter which provides a quaternion estimation as the algebraic solution of a system from inertial/magnetic observations. To develop the basic sensor fusion algorithm some procedures including a simple calculation to deal better with non-gravitational accelerations, decrease the effect of magnetometer in the presence of distortions and online gyroscope bias estimation is added. Also, a method for classification the different types of... 

Examples from recent years, such as Covid-19 disease and earthquakes, show that disasters can have devastating effects on a community.These disasters are divided into two categories: expected and unexpected. decision makers cannot easily determine the time, severity and effects of them. Therefore, they must coordinate their decisions in the pre-disaster and post-disaster stages according to the incomplete information available, and according to the dynamics of the situation, quickly understand and interpret the connections between different decisions. Among the various approaches, the decision support system can explore the variable and unpredictable nature of such issues and enable decision... 

Risk is an uncertain event or condition that, if it occurs, has a positive or negative effect on a project’s objectives. Identification and assessment of risk in a measurable way are so important for project managers to decide better. This thesis studies how to identify and assess the project’s risks in Fishery industry based on the Project management body of knowledge (PMBOK 2008) as a global standard. Constructing an aquaculture site in Abadan city has some risks which are identified in the first steps of the study and in the following steps these risks will be prioritized by the use of qualitative analysis and figured out which risks have major effects on projects objectives. In last step... 

Supported by a rich literature in psychology and neuroscience, the dual-process theory of decision making assumes that individuals’ decisions are made through arbitration between habitual and goal-directed processes within their minds. Whereas the goal-directed system makes decisions after deliberating all positive and negative consequences of each feasible choice, the habitual system make choices based on the habits formed in previous experiences. Although the decisions of the goal-directed system are always more optimal that those of the habitual system, but due to that fact that the goal-directed system is slow, effortful and time-consuming, it is sometimes more efficient to make... 

Due to increasing air pollution and traffic jams, cities are trying to promote non-motorized modes of travel. Therefore, people are encouraged to take ad-vantages of walking to decrease usage of motor vehicles and to enhance their health. Knowledge about pedestrain behavior helps planning and provision of efficious facilities for walking. To address the issue, it was decided to examine pedestrains behavior in Tehran Bazaar. The vicinity of Tehran's old Bazaar is considered to be one of the populous, important commercial centers of Tehran and one of the most spacious footpaths. Behavior analysis is done in both macroscopic and microscopic levels. In the macroscopic analysis the re-lationship... 

Today, with the development of technology, cyberattacks are on the rise. Personal and corporate computer systems can be exposed to various threats and dangers of hackers and malware, including information theft, forgery, and denial of service, which can cause great material and moral damage to individuals and organizations. So, it is necessary to take security measures in this regard. Many security mechanisms are available to prevent security vulnerabilities against various threats. In this study, first, after carefully studying network attacks, we identify the criteria for identifying attacks that can be executed in network traffic and explain how to calculate them. The current research... 

Knowing different groups of customers and building effective communication with them in such a way as to guarantee the future economic interests of the organization is a very important issue in today's businesses. The attraction of profitable customers, as well as the preservation of valuable old customers, are both important, except for the precise identification of their features. The value of customer longevity plays an important role in customer segmentation, and there are numerous researches that focuses on customer value with the aim of making more profit for the organization, most of which have life-cycle customer value models as the main inputs for segmentation cCustomers have been... 

The present research investigates the conjunction of two areas of pricing and negotiation techniques to find a relationship between price and other key factors such as quality, quantity, time, etc. and observe the overall effect of these factors on how to design and implement negotiations over price in B2B environment. The research presents a model to describe the process of negotiation and applies quantitative methods to rank negotiable scenarios. This set of scenarios, then is sorted in a triangular model of negotiation strategy and is used as a roadmap for negotiation. Furthermore, researcher evaluates effective tactics and their implementation to drive negotiation sessions based on... 

Financial benefits are no longer the only decision makers’ criteria and they consider environmental and social merits due to the modern nature of management and international competing. As a result, sustainable supply chain management (SSCM) rises noticeably in popularity among academics for researching on it and industrialists for applying it. Having reviewed respective researches, The SSCM is addressed by an integrated approach in this rsearch for selecting green suppliers and finding optimal production plan in two phase. In first phase, thank to related literature, a framework including environmental criteria is purposed for evaluating suppliers by Analytic network process method (ANP).... 

As the size and the scope of infrastructure projects have expanded, so has the array of stakeholders, either involved or affected. Such projects frequently take years to come together and develop over time through the efforts of project promoters and the participation of various stakeholders. Stakeholders through participation and input will help to legitimize and develop large scale project initiatives.This study used a longitudinal multiple case study approach that analyzed two tolled fixed crossing megaprojects. Activity research hits benchmarks before and after developments and shifts in participation strategies and stakeholders. Subsequently, we identify the main and key issues related... 

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... 

The present study investigates dynamic pricing in case of urban transportation operators competing on an identical network. Game theory has been adopted as an approach to the modeling and solutions.Game theory is a mathematical theory widely applied in competitive situations.The proposed model takes the players’ interdependency problems into account to predict their decisions as well as the displacement on the network about equilibrium point. The problem is modeled in no-cooperation state using the dynamic Nash equilibrium; Gauss-Seidel algorithm is used for the solutions considering the discontinuity of the decision space. A comprehensive sensitivity analysis has also been conducted on the... 

Wireless Body Area Networks(WBAN) consist of some sensor nodes placed in or inside the body and reportmedical data to a central node. The most important application of WBANs will be in medicine for monitoring of patients. In this applicationthe battery not only occupies a significant volume in the node but also itcan’t be changed easily,specially in implanted nodes case. On the other handas WBAN is used to report vital information, it should be reliable. Hence, the most important issues in WBAN design are both energy constraint and reliability requirement. Most of works in the literature, utilize Time Division Multiple Access (TDMA) with a central node to dynamically control the transmission... 

After three decades of research, the concept of emotion as an aspect of initelligence in artificial systems, is still unclear. Most of emotion models in AI are aimed to simulate the emotional states of human in differenct levels of abstraction and functionality. Therefore, the concept of emotions in artificial systems is completely dependent on human being’s emotional states and can not be used as a general tool for improving the intellingence of artificial systems. In this thesis, we have tried to show that defining emotion in a more abstract level can expand the domain of its appications in AI. According to some existing theories about emotions, we modeled emotions as local semi-soloutions... 

Sample efficiency and systematic generalization are two long-standing challenges in sequential decision-making problems, especially, in reinforcement learning settings. It is hypothesized that involving natural language in conjunction with other observation modalities in decision-making environments can improve generalization due to its compositional and open-ended nature, and sample efficiency due to the concise information summarized in relatively short linguistic units. By exploiting this information and the compositional structure of the language, one can achieve an abstract and factored understanding of the environment and the task at hand. To do so, it is necessary to find the proper... 

Rail transport system plays an important role in the development of the economies of the countries. This system is worn out over time by operating and weather conditions and requires maintenance and repair. One of the objectives of maintenance operations is to maintain tracks in an acceptable level and prevent their excessive deviation from the optimal situation. This deviation is called geometric irregular deviation. If these irregularities go away, they can cause traffic accidents and derailment in addition to losing travel convenience. So avoiding the deviation of the tracks is a very important. Maintenance management systems in the past few decades have been considered by the experts in... 

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...