Sharif Digital Repository

Price stickiness which is measured by indicators like frequency and duration of price changes affects how monetary policy plays a role in economy. In fact, price stickiness determines how monetary policy affects economy’s real variables like output and unemployment. Hence, price stickiness is in favor of monetary policy since it provides the ability to improve real variables in the short term. Discovering the factors affecting price adjustment also allows the monetary policymaker to be able to predict changes in pricing behavior to some extent by monitoring the changes of these influential factors. This study seeks to answer several questions using 84 million monthly price observations of... 

Oil and gas production from oil reservoirs is significantly affected by rock and fluid properties. Relative permeability and capillary pressure are two key flow functions that are used in the numerical modeling of processes related to the porous environment of oil and gas reservoirs at the core scale and above. The use of incorrect relative permeability and capillary pressure curves can lead to inappropriate prediction of the future behavior of the reservoir, which in turn affects future management decisions. Due to the time-consuming nature of obtaining flow functions from the steady state method, history-matching techniques are generally used to estimate these functions as accurately as... 

Gravity drainage is known as the main mechanism for Enhanced Oil Recovery (EOR) in naturally fractured reservoirs. In fact, this mechanism is active in gas invaded zone. In spite of numerous researches in the area, the literature suffers from the lack of a comprehensive model for controlled gravity drainage. Calculating the accurate oil recovery and ultimate recovery factor is inevitable for a successful field development plan as well as enhancing oil recovery. To obtain the accurate values of the aforementioned parameters, an accurate model to solve nonlinear differential equations is necessary. To this end, COMSOL, the well known commercial CFD software, has been used for the modeling of... 

The actuation mechanism of the tip of the laparoscopic instrument is the main problem in designing the process of miniature scale motorized instruments especially when high level of functionality and multi degrees of freedom (DOF) are concerned. Previous studies suggest local actuation as the best design for this kind of end effectors. In the present study, different actuation methods of needle holders were reviewed, related capabilities and drawbacks were evaluated and a hybrid local actuated design was appointed. The hybrid design included a micro DC motor and a PZT actuator. The main idea behind it was to combine the advantages of DC motors and piezoelectric (PZT) actuators in providing... 

Over the last years, terrorist attacks and accidental explosions have brought on a need for research in the field of structural engineering to study the response of a building subjected to blast loading conditions. An explosion within or surrounding a building, not only can have disastrous effects causing both structural damage or failure, but may also lead to the death of human beings.In order to prevent these catastrophes and gain a better understanding of responses of the buildings and lateral resisting systems with different characteristics, the study of the behavior of the lateral resisting systems under blast loading conditions is essential. This research will also aid in the... 

In this research plastic deformation analysis of high carbon steel wire in one and more pass wire flat rolling process using the finite element method (FEM) has been investigated. The effects of changing rolling pass number, length of wire, mechanical property of roll, rolling speed and friction between roll and wire in calculated results have been studied and with the main process parameters are compared. Then, the damage and failure of wire and that’s steady state cross-section is examined by model of Johnson cook damage criterion (JC). The results suggested that reduction in height of the wire affects the rolling process parameters such as strain, damage and the cross-sectional geometry... 

Government intervention in markets may go beyond the market regulation. Interventions may cause some idiosyncratic price distortions. It means the relative prices of factors to become different among firms. Therefore, micro conditions for firms will be changed. These will result in misallocation of factor production between firms and change in manufacturing TFP. According to data from about 14000 medium and small industrial firms in Iran, removing misallocation of production factors (capital and energy) and output idiosyncratic distortions between industrial firms would result in 115 percent increase in manufacturing TFP.

 

The purpose of this research is the extraction of socio-economic factors (separation of household and household members) that affect the use of banking services in urban area of Iran. In this study we used data of the "family access to financial services in urban areas of Iran in 1387" that has been sampled by the department of economic statistics of central bank of Iran. The statistical information of this organization is in form of completed questionnaires and based on household addresses in a city and contains of 6055 urban household's information. In this project 15922 persons have been studied in urban households include the caretaker and the other family members. In addition to... 

Due date assignment for customer orders has been studied in various production environments. In this thesis a production system is considered in which the orders of several customers are produced in a single lot because of the economy of scale. If a lot is completed before receiving customer orders, inventory carrying cost is incurred. On shortages, a due date is quoted to customers and lead time quotation cost is incurred. The due date may not be met because of (lead-time) uncertainty in production system. Hence if the order is delivered after its due date, tardiness cost is charged. The literature reviews show that such a model is not considered by other researchers. Two different problems... 

A hierarchical production system in make-to-order environment is presented in this thesis. This production system is consisted of three different decision making levels. Maximum acceptance for production within customer specified time interval was done in the first stage, which is called order arriving stage, based on different client criteria, type of demanded product, and production system constraints. A new hierarchical decision making structure for accepting or rejecting arriving orders is proposed in this level. The output of this acceptance level is orders having maximum production system defined criteria, and minimum production cost along with order delivery time with minimum delay is... 

The study on the propane dehydrogenation process has been receiving significant attention due to the growing demand for propylene. The aim of this research is to develop an appropriate kinetic mechanism for dehydrogenation of propane over an industrial Pt–Sn/γ-Al2O3 catalyst in the presence of a very small amount of water. The reaction is carried out over the temperature range of 575 – 620 º C at atmospheric pressure. The results showed that a small amount of water and methanol can improve the performance of catalyst and also, increase the selectivity to COx. Addition the 0.5, 0.45, 0.3 water and 0.1, 0.05, 0.02 methanol are the optimum amount of these oxygenated compounds in order at... 

In recent years in assembly line balancing area many researchers have focused on identifying and modeling real world situations in assembly lines in order to obtain more suitable model. As a result many generalized models have been developed in assembly line balancing area. However, designing efficient algorithms to solve these generalized problems has just begun. In this study it is aimed to design efficient algorithms to solve one of these generalized problems. Specificcally two hybrid genetic algorithms (GA) are proposed to solve assembly line balancing problem with sequence dependent setup times. Scheduling of tasks in the stations has been less considered in the literature of assembly...