Sharif Digital Repository

Dynamic reconfigurability in optical and mobile networks can facilitate heterogeneous service provisioning while utilizing minimal resources. This allows cost-efficient service delivery resulting in increased revenues for network operators. Deployment of elastic mobile and optical networks is a key driver for enabling reconfigurability in modern networks. Elastic optical networks can be utilized as the fronthaul portion of new generation of mobile networks. Such elastic optical fronthaul networks facilitate joint reconfiguration of flexible radio and optical elements and provide considerable performance improvements. This thesis focuses on the joint dynamic selection of functional splits and... 

Reducing the size of transistors has dramatically increased the impacts of NBTI, HCI, and EM phenomena in comparison with decade ago. These phenomena are able to have influence on properties of different parts of a chip to make it changed gradually; including threshold voltage of a transistor and electrical conductivity of interconnections. These changes are known as the aging of a transistors that diminish the performance and reliability of a chip. A common reason that plays a significant role in all these phenomena is temperature. The temperature becomes more important when the power density increases per unit area due to decreased size of transistors, which is a trend in multi-core... 

Deposition of solid particles present in the process air on the walls of furnaces is one of the challenges in industries. This phenomenon has various causes. For example, in a furnace, the temperature of particles increases as they pass in front of the furnace burners, and due to the softening of the particles, their chances of deposition increase when they collide with the walls. Over time, with the growth of deposited particle layers on the combustion chamber walls, the performance of the combustion system gradually becomes impaired. present research aims to design air jets intersecting with the process air path, with the purpose of reducing the temperature of particles prone to deposition... 

In many papers, GDP is used as a measure of economic growth, which is shown to possess a nonlinear structure. The study focuses on the nonlinear Granger causality between liquidity, government spending, oil revenues and economic growth by markov-switching vector autoregressive and markov- switching Granger causality approach for the period of 1369-1397 for Iran. The empirical results from MSAI(2)-VAR(4) suggest that Oil revenues and government spending have a significant impact on economic growth in both regimes. Also, markov- switching Granger causality results are quite different from the traditional Granger causality results, that suggests the nonlinear Granger causality has more... 

The use of microelectrode arrays in neural networks has offered a wonderful opportunity for evaluating numerous properties and interactions with excitable tissues such as the brain and spinal cord in the laboratory. In neural network applications, microelectrode arrays can be utilized to analyze nerve impulses or interact with neurons. They are either used to record neural data or to stimulate spinal cord nerves. Previous research has revealed that stimulating the spinal epidural region can help restore after spinal cord injuries (SCIs), which is the key to using them in the rehabilitation of living beings, including humans. According to the international campaign for the treatment of SCI... 

In this study, at first the V2O5 spent catalysts were characterized. The aim was to identifying whether these catalyst may be regenerated. Then, for feasibility study of them, three methods were applied: washing, diffusion and milling the spent catalysts for their subsequent reproduction. A variety of techniques such as XRD, XRF, AAS, TPR and TPO were applied in order to identify factors contributing in vanadium pentoxide catalysts deactivation. The results showed that approximately all of pollutants caused their performance deterioration, while they still have some active phases. Then, the polluted catalysts were washed (their yield increased from 43% to 72.2%). In the underside of the... 

Individuals have been regarded as independent decision makers in the majority of transportation analysis. However, individual behaviors are usually affected by the interactions between the members in group decisions; and consequently, individual decision making paradigm could result in less-accurate predictions. Besides, as the data used for travel demand modeling typically comes from household level surveys, the idea of random sampling holds at household level and not the individual; and therefore, individual information would not be consistent with the theory of the discrete choice models when the household is the actual sampling unit. The present paper aims at modeling the way that... 

Traffic safety is one of the fundamental part of the transportation planning which is led to lowest the number of crashes and its following consequences by in-depth studying. Thus, determining the severity of accidents, including damage, injury and fatal injury is very important. The aim of this study is analysis of the accident-injury severities in single-vehicle and multi-vehicle crashes and providing the policies in Iran. The approach used in this study to select the most effective parameters of the injury-severity is based on the data gathered in Iran Road Maintenance and Transportation Organization during the year 2011. Accident probabilistic model based on analysis of relations among... 

Spatial transferability of behavioral models can significantly decrease the costs and time required for transportation studies. The main aim in this study is exploring transferability of MDCEV joint model used for activity type and duration choices with implementing various transfer methods on different sample sizes. In order to achieve this goal, full information of comprehensive transportation studies conducted in Mashhad 1994 and Shiraz 1999 has been employed. Shiraz city is the region where the model is generated using its data and Mashhad is the region which the generated model is transferred to. Transfer methods studies in this study are Transfer scaling, Bayesian method, Combined... 

Car usage-based insurance is recently introduced to the market of car insurance and because these contracts are new in this market, Insurers and other beneficiaries are eager to know about the outcome of them. In this study, the outcome of these contracts and equilibrium of the market have been analyzed from the view of insurers. An insurer as a profitable firm want to analyze its costs and benefits, and as a result, one of the most important factors from the view of the insurer is the cost-benefit analysis when the insurer enters into the new market of usage-based insurance. For this analysis, by contract selection and insurer loss payment data, insurer cost and benefit forecasting models... 

Auto insurance premiums are currently part of car ownership fixed costs in Iran. As driver behavior and driven distance, in spite of their significant impact on driver’s risk, are not considered in these costs. Distance-based models are introduced to enter usage costs to premium calculations and affect drivers’ behavior. Achieving benefits of this plan demands evaluation of profits and implementing costs of it. This research aims to provide guidelines to influence drivers’ behavior alongside with studying the distance-based insurance market in Iran. Required data collected using a field survey in Tehran car technical inspection centers, by representing four different plans to 980... 

With the growth of the urban population and the increase in private car ownership, negative implications of transportation, such as traffic congestion and environmental pollution has increased. A good solution to this problem is development of traffic infrastructures. However, it is not sufficient by itself and better management strategies for solving these problems are needed. One of the related approaches, is high occupancy toll lane. The main purpose of this study is modeling user’s mode choice behavior in the presence of high occupancy toll lane and pricing some highway lanes in Tehran. Another important purpose of this study is to find affective factors that have an influence on users... 

Hydraulic fracturing is a process during which a viscous fluid under relatively high pressure and flow rate is injected into a wellbore to induce and propagate a system of cracks in the ground.Hydraulic fracturing of underground formations has been widely used in different fields of
engineering, such as petroleum engineering, geotechnical engineering, environmental engineering, mining engineering,and so on.Despite the technological advances in the techniques of in-situ hydraulic fracturing, the industry lacks a realistic and reliable numerical model to design cost - effective and efficient hydraulic fracturing treatment.This is due to the complex interaction and strong coupling between...