Sharif Digital Repository

In this dissertation, we will attempt a discussion of some ethical implications of genetic enhancement and present an argument against certain group of enhancements. We will demonstrate that this discussion requires a distinction between therapy and enhancement, therefore the arguments for and againt this distinction will be examined but it will be adopted in the end based on its merits. We will also show how genetic enhancement is a real possibility that will be available for consumers in the near future; and how probing the ethical issues surrounding the technology is quite necessary. We will then turn our focus to different theories of normative ethics and an examination of their merits... 

The aim of this thesis is to introduce some algebraic topologies methods and apply them on fining the chromatic number of some famous graphs and also hypergraphs. In the first part, we will use a mixture of two well-known technics, Tucker lemma and Discrete Morse theory to find an upper bound for the chromatic number of s-stable Kneser for some specific vector s. to find the sharper upper bound, we will deviate our strategy and use another approach by finding an edge-labeling and apply some theorems in POSET algebraic topology. In this way, we also find a connection between Young diagrams and the numbers of spheres in the box complex related to Kneser graphs and hypergraph. Actually, we can... 

In auction-based cloud investment environments, consumers desire the least possible cost and high satisfaction, while providers seek strategies to maximize profit and return on investment. In these environments designing an adequate resource allocation that can satisfy both consumers and providers is of utmost importance. Yet, most available models in resource allocation focus on providers’ needs and do not concern themselves with the consumers. Therefore the present study aims to present an efficient and optimum model for resource allocation problem that takes into account various factors, e.g. resource price, service quality, reputation and fairness, and is capable of satisfying all honest... 

With the daily increase in the volume of information and due to the growth and pervasiveness of wireless networks, the structures and the way of connection of intermediate nodes have become very important in terms of energy, communication speed and communication overhead. In this thesis, we examine the structure of directionless wireless networks assuming nodes are selfish. In these networks, nodes seek to minimize their costs while being required to access all nodes with limited path length. Due to the selfishness of nodes, we used game theory to analyze the structure and behavior of nodes by calculating the Nash equilibrium state and to compare these networks with networks that are managed... 

English research articles (henceforth RAs) have evolved into a vital medium for conveying and disseminating scientific knowledge. Mastering textual and linguistic conventions of academic prose assists English native and non-native authors in writing scientific RAs. Lexical bundles (LBs) refer to word combinations that co-occur frequently in a particular register (Biber, Johansson, Leech, Conrad & Finegan, 1999). In fact, they are an integral component of “fluent linguistic production” (Hyland, 2018, p. 4). For more than a century, LBs have attracted researchers' attention in corpus-driven studies, although the extent to which LBs vary between English native and non-native authors remains... 

Natural gas contains small amount of benzene, toluene, ethyl benzene and meta-xylene (BTEX). These compounds are soluble in amine solutions and accumulate in aqueous amine solution during sour gas removal process. They produce problems such as foaming in amine adsorption columns. The aim of this work is to study BTEX removal from aqueous amine solution by means of activated carbon. Three different commercially available granular activated carbons were used in experiments. Experiments were divided in static and dynamic adsorption categories. In the static tests, equilibrium adsorption of all three activated carbons were performed and the most effective activated carbon sample determined by... 

Hybrid photovoltaic thermal system (PV/T) is a pioneer mechanical and electrical system which can produce both thermal and electrical energy for domestic or industrial purposes. As the solar cell’s material is semiconductor, the electrical output of them reversely modifies with the reduction of solar cell’s operating temperature. One of the most operational and cost-effective methods that has been investigated is active cooling. The photovoltaic panel cools down with a channel under the PV’s rear surface and a fan in the channel outlet. The producing heat can warm up cold water of a house or a factory. In addition to active cooling, it is smart to utilize passive cooling such as artificial... 

In this study some experiments were performed to investigate the effect of sweep angle on the transition location of laminar flow to turbulent flow. Three half wing models were used, each having a different sweep angle but with the same aspect ratio in various angles of attack. Two flat plates were used at the ends of the swept wing models to prevent the flow from rolling up over the wing. By simulating flow over infinity swept wing by eliminating tip vertices, the effect of sweep angle on flow transition phenomenon was investigated.
The experiments included the study of transition flow via hot-film sensors, which were glued on the wing surface. We found that the small leading-edge... 

Fossil fuels provide the most needs of the world's energy, however, continues to lead to two key problems. The first problem is their limitation, and the second problem is the creation of serious environmental issues. Therefore, the need for renewable energy sources is felt more than ever.As an energy source, hydrogen is the lightest, most efficient and cleanest fuel. One of its unique properties is efficiency, the production of electricity by fuel cells through the electrochemical process, has far greater efficiency than of mechanical energy production from fossil fuels in internal combustion engines or energy production in thermal power plants. A fuel cell is a device that converts... 

Video encryption algorithms have become an important field of research nowadays. As the increasing rate of employing videos in commerce and other visual applications , the security of video data is becoming more vital. A digital media can be transmitted easily in real time everywhere at any time due to the advanced development of communications, Internet and multimedia technology. As a result information availability has increased naturally with the introduction of mobile devices. However, this availability faces with the problem of maintaining the security of information that is transmitted in public channels.
The new version of video coding standard that is... 

Implant primary stability is a crucial component of implant survival. Primary mechanical stability is correlated with implant type, surgical technique, quantity and quality of bone at the recipient site. Since bone integration (BI) significance has been acknowledged, a variety of techniques have been developed to quicken BI and achieve faster fixation. Studies have shown that material type, and many surface properties, including as surface composition, roughness, topography, and energy, have a significant influence during the early stages of bone integration to the implant. In this work, we did synthesis one-dimensional nanoneedle-like arrays of hydroxyapatite using the injection method... 

Recently, advances in the fabrication and integration of sensing, communication technologies and economical deployment of large scale sensor networks which are capable of large scale target tracking, become possible.therfore, the wireless sensor networks are a fast growing and marvelous research area that has attracted considerable research attention in the recent past. The creation of large-scale sensor networks interconnencting several hundered to a few thousand sensor nodes opens-up several wide range of application and technical challenges. Sensor nodes have been deployed to play significant roles in battlefield, disaster-prone area, traffic control, habitat monitoring and intruder... 

For many reasons the Montecarlo method is chosen for investigation of problems like shielding. Nowadays, superiority of utilizing the codes based upon Montecarlo methods such as using cross sections with continuous energy or using exact models of complex geometries, is obvious for everyone. But obtaining results with least possible variance is extremely important. variance reduction methods usedfor achieving exact results with less calculating time. Up to now in the MCNP codes, many methods have been utilized for reducing the variance. One of the methods which have recently attracted attentions is using the importance function. For obtaining importance function we need to solve the... 

One of the most vital aspects of understanding the traffic phenomenon is scrutinizing the traffic transition status, such as the transition from free flow to congestion. The Percolation Theory is a renowned theory focusing on analyzing various network types to detect the critical zones, which are the zones including links that are important to control to improve stability. By calculating the quality indices of network links, the Percolation Theory can simulate the traffic percolation propagation in the network and determine possible critical zones for further analysis. Most studies in this field assume access to data of several traffic parameters for the entire transportation network, such...