Sharif Digital Repository

According to the principle No. 44 of the Constitution of the Islamic Republic of Iran, Roads are in the public domain and are at the discretion of the Government. The result of this rule is that there is always a free route on the side of the freeway and motorists have the right to choose between a freeway and its successor road. This is a perfect laboratory condition which gives the opportunity that can be used with discrete choice models to estimate the demand of freeway versus its successor. In this paper we estimate the determinant parameters of the freeway demand versus the successor road and price elasticity of demand that can be calculated separately for each path. The results show... 

Soft magnetic materials are widely used in industries such as automotive, electrical, electronics, and telecommunications. These materials are essential for electromotors, inductors, transformers, and generators. The introduction of FineMet soft magnetic alloy has been a significant development in the design and production of nanocrystalline soft magnetic materials, leading to extensive research on these types of alloys. This particular study investigates the impact of applying an external magnetic field on the magnetic properties of Fe82.9Si4.2B12.3C0.6 amorphous alloy. The study begins by examining the kinetics of α-Fe phase crystallization using DSC. The results indicate that the... 

In this thesis, we propose a first-order interior-point method for linearly constrained smooth optimization which was recently proposed in the literatuare that unifies and extends first-order affine-scaling method and replicator dynamics method for standard quadratic programming. Global convergence and, in the case of quadratic program, the (sub)linear convergence rate and iterate convergence results are derived.The method is implemented and numerical experiments on simplex onstrained problems with 1000 variables is reported  

This research enlarges the content of the literature related to the business switching behavior by examining why dissatisfied customers remain in relationship with their existing service provider and do not exit, in the business to business context in Iran. The study develops and tests a model investigating the factors which potentially affect on dissatisfied customers to stay in relationship and also perform upon their repurchase intention. The proposed model specifies a set of propositions among dimensions of switching barriers, switching cost, interpersonal relationship, lack of attractive of alternative, dependence, calculative commitment, service recovery, inertia, lower price, method... 

Hip replacement surgery is performed with the aim of relieving pain and restoring the normal function of the joint for patients who are in the final stages of arthritis. Standard prostheses offered by implant manufacturers come in a wide variety of models and sizes to meet the needs of patients. However, these commercial prostheses may not be suitable for patients with significant bony abnormalities, leading to implant instability and loosening. In such cases, a suitable solution is to use customized implants that are specifically designed to match the patient's unique anatomy. The purpose of this research was to design a customized cement stem for hip joint replacement surgery in patients... 

With the continued improvement of sequencing technologies, the prospect of genome-based medicine is now at the forefront of scientific research. To realize this potential, however, a revolutionary sequencing method is needed for the cost-effective and rapid interrogation of individual genomes. Generally there are key factors in the definition and evalution of sequencing methods: 1-read length, 2-throughput, 3-read accuracy, 4-read depth, and 5-cost per base. The purpose of developing new sequencing methods is making better at least one of these factors. In order to reach the goal of rapid and low-cost sequencing method, one cannot rely only on current techniques. Improvements of current... 

Nowadays, due to the growing need of the human to further improve the health of the community, research in the field of pharmacology as well as simulation of the cell culture environment is increasing. One of the most important requirements for simulating cell culture is the use of concentration gradient in culture media. The reason for this is the dependence of cellular activity on the presence of a gradient of concentration in the environment. Also, in drug investigations, in order to speed up the examination of different drugs and reduce the amount of drug that will used, different concentrations of the drug should be considered simultaneously in the microchips. Therefore, to make the... 

Statistical studies indicate the fact that in Iran, like many other developing countries, a significant percentage of buildings are made of traditional materials and most of them are adobe buildings especially in rural areas. Furthermore, geological data indicates that Iran is located in alps-Himalayas seismic zone and exposed by destructive earthquakes and adobe buildings suffer the most damages comparing with other type of the structures. According to these explanations, this research deals with adobe buildings behavior and provides solutions for reinforcing them and improving the seismic response of these buildings. These studies include numerical modeling with finite elements methods by... 

In the current situation of energy, gas storage is one of the basic needs. Different methods have been used in order to storage gases. One of these methods is the adsorption of gases on solid materials, which are called as adsorbents. In recent decades, different gas adsorbents, such as silica gel, zeolite and activated carbon, have been studied. Most of these adsorbents are nonorganic materials. Recently, many researchers have tried to apply polymeric materials as gas adsorbents. In this regard, the obtained results on the different polymers showed that it is possible to achieve the proper gas adsorption. In this study, different samples were prepared from polysulfone by phase inversion... 

In this thesis we consider the problem of distributed computation by many processors.We mainly concentrate on matrix multiplication problem in this thesis because of its importance. A distributed system consists of N worker processors and one master processor. The master processor should distribute the computation between workers and after computation in each of them, collect the results. In this thesis, we are going to mitigate the effect of straggler processors by using coding methods. Straggler processors can cause delays in the computation time.In this thesis, we firstly introduce a method to multiply any number of matrices in each other. The proposed method occurred in one shot without... 

The main goal of current investigation was partial reduction of Fe2O3 available in Hematite-rich ore to Magnetite by Fludization Bed method. The reductive gas, CO, was produced by incomplete combustion of Acetylene and Airmixed in inappropriate ratio. X-Ray Diffraction and X-Ray Florescence analyses were implemented in order to conducting qualitative analysis of present phases before and after reduction of the ore. Quantitative analysis of the same phases was also conducted by Titration. The latter analysis revealed the precise magnitude of available iron in each of the oxide containing phases. The chemical composition of the reactor gas was also determined before and after reduction... 

Abstract The problem of competetive facility location can be defined as follows: There are a number of customers in the form of points in space, and two players arrange a number of facilities in the form of points in space, given some limitations, respectively. Each customer’s connection to each facility has a cost for the customer and an advantage for the facility, and each customer wants to be connected to at most one of the facilities which has the lowest cost for him. The goal is to find the strategy of placing the facilities and determining the cost which the facility receives from the customer, in such a way that the player’s profit is maximised.In this thesis, we first sought to... 

Zero knowledge proofs allow a person (prover) to convince another person (verifier) that he has performed a specific computation on a secret data correctly, and has obtained a true answer, without having to disclose the secret data. QAP (Quadratic Arithmetic Program) based zkSNARKs (zero knowledge Succinct Non-interactive Argument of Knowledge) are a type of zero knowledge proof. They have several properties that make them attractive in practice, e.g. verifier's work is very easy. So they are used in many areas such as Blockchain and cloud computing. But yet prover's work in QAP based zkSNARKs is heavy, therefore, it may not be possible for a prover with limited processing resource to run... 

Lightweight clients are a type of blockchain users who do not store all the blocks in the blockchain due to limited resources. These users store only a small part of each block and when needed, request transactions from full nodes that store the entire blockchain. These users have no role in block validation and only want to receive transactions related to their addresses with proof of the inclusion in the block from full nodes.Since light clients rely on full nodes for receiving transactions, their privacy against full nodes is important. The current implementation of Bitcoin uses Bloom filters for privacy, but this offers very little privacy to the users.In this thesis, we study the...