Sharif Digital Repository

In Spatial Voting Theory, distortion is a measure of how good the winner is. It is proved that no deterministic voting mechanism can guarantee a distortion better than 3, even for simple metrics such as a line. In this study, we wish to answer the following question: how does the distortion value change if we allow less motivated agents to abstain from the election? We consider an election with two candidates and suggest an abstention model, which is a more general form of the abstention model proposed by Kirchgassner. We define the concepts of the expected winner and the expected distortion to evaluate the distortion of an election in our model. Our results fully characterize the distortion... 

In this thesis we are going to improve an ultrasonic flowmeter accuracy by considering the influence of different parameters like temperature, pressure, etc. Firstl of all different cases of flow condition in which ultrasonic flowmeter may work are specified, then velocity and temperature profile of pipe flow are determined using Fluent software. In thr next step ultrasonic pulses transmitted are simulated by the use of code written in Matlab to find wave travel time in the flow. Evetually an accurate relation of calibration for flowmeter is determined by the use of travel time and all other flow properties to evaluate the accuracy of flowmeter in diffent cases. Relation extracted can be... 

Polymerase Chain Reaction (PCR) is a laboratory method for amplifying a part of DNA. This method is used in determining the sequence of genes, detecting pathogenic agents in epidemics, creating genetic changes in bacteria, diseases, plants and even animals. Many factors affect the quality of the reaction. Each of these factors can be effective in amplifying the target in DNA. If we can predict the result of PCR using the factors involved in the reaction, it will save a lot of money and time. The aim of this research is to predict the result of PCR amplification using machine learning methods. For this purpose, two methods are proposed: feature-based method and string-based method. In the... 

In this thesis, the value-ladenness or value-neutrality of technology, new social media and as a result Instagram is investigated. It is also discussed whether values can be taken into account during the design process of technical artefacts, including new social media and Instagram, and methods are developed for this purpose. Several methods have been developed for this purpose, some of them and their compatibility with modern social media are explained; including the Value-Sensitive-Design method and the disclosive computer ethics design method. The frameworks of ethical philosophy such as virtue ethics are reviewed and the appropriate ethical framework for the analysis of new social media...