Sharif Digital Repository

Metastatic bone is one of the most common causes pain in cancer patients. Because of Sm-153 emits gamma and beta, Sm-153 have been used for both of the diagnosis and treatment of metastases; Also Tc-99m have been used for the detection of metastases. Dosimetric studies in targeted radiotherapy require an accurate quantification of activity existing in different organs of a patient, which can be estimated from scintigraphic images. Quantitative imaging is difficult to perform because of several physical phenomena, such as scatter and attenuation, which lead to errors in activity determination and nuclear medicine image degradation.
In this work, we must determine the optimal... 

In recent years, different of nanoparticles as oil additives has been investigated in many studies . These research show that nanoparticles are deposited on the surface friction and improve tribology properties of base oil and also significant reduction of wear and friction caused by the nanoparticles. Compared with metal and metal oxide nanoparticles , carbon nanotubes (CNT) due to the high thermal conductivity and high aspect ratio , is an excellent candidate as the nanoparticle is dispersed . For preparing useful oil it is essential to stabilize nanoparticles in fluid that will not settle over long time . Oils containing nanoparticles by increasing the heat transfer coefficient... 

In this research the performance of the Moving Bed Biofilm Rector (MBBR) in different amounts of dissolved oxygen (DO) was investigated. Reactor with a useful volume of 15 liters was used in this study. In order to obtain optimum oxygen concentration, stayed at 6, 10 and 15 hours, and at different levels of dissolved oxygen in the range 0.5 -6 mg/lit, the amount of organic material was removed respectively. Also, in two different aeration intensity of 3.5 and 5.5 liters per minute at different values of e% (percentage of filling of media) the mass transfer coefficient values were obtained. When the aeration intensity increases from 3.5 to 5.5 liters per minute, and the percentage of 40%... 

One of the most important methods of controlling discharge in water industry which is widely used in irrigation, water distribution, waste-water engineering, drainage, flood control and other water related projects, is side weir. The hydraulic behavior of flow over side weir is spatially varied flow with decreasing discharge. Various investigators have related the weir discharge coefficient as a function of main channel upstream Froude number and the fraction of weir height to upstream depth . Performance of sharp crested side weirs with extended length (as labyrinth side weir with asymmetric geometry) has been studied in this thesis. The variables for this study are height of weir ,... 

In qualitative content analysis research with the aim of identifying areas of language impairmenthigh-functioning Persian-speaking autistic children, ten subjects were observed during fifteen training sessions which were the cognitive block of a three-block training program. Each session lasted 90 minutes and was video recorded. Prior to this, focus group interviews with specialists and semi-structured interviews with mothers and parallel to that focus group interviews with mothers were handled all of which were audio recorded. After two levels of initial and second coding, a final list of areas of impairment in the language of high-functioning Persian-speaking autistic children, that... 

With the rapid development in information-communication technologies a huge amount of electronic documents has been produced and increase everyday in the world wide web. According to this wide information environment, summarization is critical for the users who digest this electronic big data. This research proposes two graph-based abstractive models for summarizing the Persian texts. A good summary should cover the overall context and the important subjects, and should be properly readable and coherent as well. Some permanent challenges in automatic text summarizations intended to increase the readability of output text, as well as covering all the main topics, and minimize the redundancy.... 

Death can be the result of severe bleeding which is associated with the loss of a high amount of blood like what happens in accidents, wars, or operations. Classic methods to stop bleeding are mostly ineffective to decrease the hemostasis time and the volume of the lost blood. A wide variety of products like powders, foams, and hydrogels have been designed and synthesized either from natural or synthetic polymers. However, limitations like weak tissue adhesion, creating a moist environment in the wound site, infection, weak biodegradation, and hemolysis still have remained. Among the existing options to be used as hemostasis agents, polysaccharides can be appropriate considering their great... 

This thesis was an attempt to find the effect of having multi-domain conceptual network on metaphorical creativity. The purpose of this research was to answer the following question: By extending and expanding the mental conceptual network, could one increase their potential creativity; In other words, is expansion of the mental conceptual network one of the parameters of creativity or not.To answer this question, a questionnaire and a test were developped. Through the questionnaire, we divided the sample group into the test and control groups. And the test indicated how creative each individual is.There were three different ways the sample group was divided. The criteria for dividing the... 

In the transportation litreture, many different algorithms have been proposed for solving traffic assignment problem based on the user-equilibrium principal.These algorithms are devided into two main groups: Path-based algorithms and arc-based algorithms. In the past, arc-based algorithms has attracted quite attention, but recent scientific progress in the computer science changed this viewpoint to the state of path-based algorithms. Much of the attention has been focused on three particular algorithms: the complementarity (C) algorithm, the gradient projection (GP) algorithm and the disaggregate simplicial decomposition (DSD) algorithm. In this thesis, these three algorithms have been... 

One of the ways for semantic modelling of natural languages is to use the distributed representations of words. Formerly in order to produce the distributed representations of words several methods like LSA, LDA and other techniques taken from information retrieval were applied. The main idea presented by these methods is that the whole document consists of one central topic that has become hidden by the words it is made of. These models assign one general meaning to the whole document and do not regard words as semantically independent. However, each of the words of a document have specific senses that these models are not able to reflect. On the other hand efforts done in the field of... 

Contact happens when two bodies collide. Depending on our assumption, it can be considered as a frictional or frictionless contact. Here we have assumed that friction accompanies the contact phenomenon, hence it is called a frictional contact. For modeling contact problems, different procedures can be used such as node-to-node or node-to-surface patterns. Here we want to use the node-to-surface procedure to model the contact problem. The node-to-surface pattern has the capability to model interface behavior between different materials. By using the finite element method through numerical computations and also by applying constraint conditions which are related to contact conditions, we can... 

A semantic role labeler is a software that takes sentences as inputs and identifies the words or groups which have semantic roles such as Agent, Theme, Source, Instrument etc. The correct identification of semantic rols using computers can improve the quality of many natural language processing tasks such as information extraction, question and answering, text summarization and machine translation.Therefore a considerable amount of research has been carried out on this topic. Semantic role labelers normally use features extracted from the syntactic structure of the input sentences. That is why the syntactic representation used has a prominent role in the system's outcome. The research... 

Morphological analysis of words plays a fundamental role in natural language processing applications such as spell checker, POS-tagging and machine translation. Among different dialects belonging to Kurdish, Northern Kurdish (Kurmanji), Central Kurdish (Sorani) and Southern Kurdish are the closest ones to each other. The central dialect of Kurdish is the second official language in Iraq and a large volume of text content is producing daily in this dialect. In this research, designing and implementation of a two-level morphological analyzer for the central Kurdish dialect is introduced. This analyzer is designed using an open source toolkit named HFST, which is a finite state transducer...