Sharif Digital Repository

ISO 10303 Standard also known as STEP, is an standard in the domain of mechanical manufacturing that describes data relating to drawings, design, machining, process planning, engineering and other aspects of product which all together can describe the entire life cycle of products. However, as this standard is newly born and developing these data models are expensive and time consuming, so far, no data model for description of cutting tools is developed. In this project we study the STEP parts and protocols to understand how data is stored. We study EXPRESS Modeling language, the language developed as part of the STEP standard which is the official language of data modeling in STEP. And use... 

Question and answer systems offer a means to acquire information in various formats. One such method is conversational question and answer, where the system possesses a text containing the information and, through a series of exchanges, provides the user with the needed information. In most systems, the responses generated by the system are either single-word or very brief, which is considered a weakness. Recent research endeavors have employed pre-trained language models to bring the system-generated responses closer to natural language. In a recent study, a system receives a set of questions along with short answers, then produces complete and fluent responses. This method utilizes parsers... 

In this thesis we study the possibility of unidirectional transmission of light using reciprocal and nonreciprocal elements. Unidirectional transmission will allow us to separate the coupling of light into and out of resonators and design unidirectional waveguides. We start by studying the effects of one-sided modulations of dielectric constant of reciprocal structures. One-sided modulation will satisfy the phase matching condition for the coupling of two waves only in one direction. Using coupled mode theory, we study one sided modulation in layered media. Next, we find the exact solution to such strucures using transfer matrix method and analyze one-sided modulation in waveguide... 

Nowadays, in many financial markets, policy makers impose daily price limit to prevent investors from making emotional decisions, which can lead to abnormal price volatility. A number of theoretical and empirical studies have been conducted on the effectiveness of setting price limit, some supporting the idea and other rejecting. In this research, we begin with a detailed analysis of magnet effect as one of the consequences of setting price limit. Then we study the stock price of five firms listed in Tehran Stock Exchange (TSE) by means of an autoregressive model with explanatory variables to determine whether or not the magnet effect exists. These five firms, put together, comprise 23% of... 

In the recent years, females’ literacy rate has experienced a drastic improvement in Iran; accordingly a remarkable increase in their participation rate is reasonably expected. Education is considered as a one of driving forces of females’ presence in the labor market; however they likely are paid less than men in some occupations or activities. This phenomenon is called gender wage gap in the labor market literature. This wage gap occurs when a worker is paid less than her counterpart with the same level of marginal product.
This study provides quantitative estimates of the gender gap in the labor market of Iran. In this end, using data on household income and expenditure, from 2005... 

In this thesis, different systems of quantified modal logic, philosophical theories of possibilism and actualism, and the interaction between these two theories and those systems have been studied.Modal claims, which talk about the world as it could have been and not the world as it is, have by far been under philosophical considerations. Possibilism and actualism, two philosophical theses that have their own point of view towards the world and its objects, analyze these claims and their relevant truth-assigning mechanisms in different ways.On the other hand, over the last century, modal sentences have been formulated, in sentencial and quantified levels, by precise logical systems, called... 

Parkinson's disease is the most common progressive neurological disorder after Alzheimer, which is associated with motor disabilities. One of the most effective ways to improve patient’s condition with this disease, is rehabilitation.Assessment of the patient during rehabilitation is very important in order to give a better understanding of patient's status to the specialist, but qualitative assessment methods in traditional rehabilitation are ineffective in fast and accurate evaluation of the patient's condition; and because of their need for patient’s attendance in clinic, they will incur huge medical costs. Therefore, the purpose of the present study is to present a quantitative method to... 

Temperature and the resulting thermal behavior of electric power generation and distribution equipment and industrial electrical systems and processes are the most critical factors in the reliability of any operation or facility. Temperature is by far the most measured quantity in any industrial environment. For these reasons, monitoring the thermal operating condition of electrical and electromechanical equipment is considered to be a key factor to increasing operational reliability. Infrared thermography (IR/T) as a condition monitoring technique is used to remotely gather thermal information for monitoring the condition of virtually all of the electrical components on an entire system and... 

Anomalous top quark interactions with gluon (tug , tcg) allow the production of single top quarks at the LHC. Two main sources of backgrounds which we took into account are W +1j and standard model single top production. In order to do it, we examine the reconstructed angular distribution of the charged lepton in the rest frame of W boson from the top quark. It is defined in terms of the angle θ_l , between the charged lepton momentum in the rest frame of the W boson and the momentum of the W boson in the rest frame of the top quark. Using this angular distribution of the charged lepton from the W boson in the top decay، we show that with the data of 10fb^(-1) of integrated luminosity and...