Sharif Digital Repository

Analyzing cardiac function of the fetus during pregnancy is proved to be an important prenatal care procedure. Traditional methods like auscultation and ultrasonography could only lead to anatomical information about the fetal heart. So in the recent decades many researches on the abdominal electrical signals of the pregnant women have been done. Nowadays, it is possible to record the heart magnetic signals. With regard to the morphological similarity between the electrical and magnetical signals of the heart and the superiority of the magnetic ones, one could assume more diagnostic capacity for the fetal MCG. It should be mentioned that finding the location of the fetal R waves could help... 

Career Orientations or career choices, can be affected by internal and external factors. External factors are the environmental conditions that the reward and the attractiveness of selecting a career choice are dependent to them. Internal factors include the needs of oneself from his/her job, his/her beliefs and his/her skills and competencies about the job. In this research the internal antecedents of managerial and technical orientations between programmers have been identified. On the other hand the perception of people about the compensation system as an external factor which can affect the mentioned relationships, have been analyzed. It seems that this is the first research which career... 

In this research, a Simulation-based Dynamic Traffic Assignment model based on parallel Processing is proposed. Dynamic Traffic Assignment has two key sub problems: Route choice modeling and Dynamic network loading. In route choice problem, a Type-II fuzzy system is proposed to model the complexities and ambiguities, which exist in the behavior of network users. The model can consider behaviors of network users in the forms of route choosing and route changing. In dynamic network loading problem, a Cellular Automata model is proposed as a microscopic simulator. Finally, In order to speed up the model and to use it in real time problems, the proposed Dynamic Traffic Assignment algorithm is... 

Due to compability of Magnesium with the body, it is a suitable material for making biodegradable stents, Althogh, its mechanical properties are not desirable for stent application. Accordingly, lately, magnesium’s microstructure and mechanical properties have been improved using various methods, including the process of severe plastic deformation (SPD). Many severe plastic deformation methods have been introduced for the fabrication of ultrafine grain tubes till now, which the process of tubular channel angular pressing (TCAP) is the most effective one. In the first part of the research, Magnesium tubes with a thickness of 1 mm were processed using the TCAP with a trapezoidal channel, and... 

New product development (NPD) is a crucial process in maintaining a company’s competitive position and succeeding in dynamic markets. One of contemporary trends in the global economy is mass customisation that bases on modifications of existing products instead of designing everything as a new project. Product development can be achieved in design, planning or production phases. Specifications of previous products deliver information of design, cost and time of past NPD projects that can be the basis for developing new products. Given the low chance of technical success, market change and high cost research, market demand, product development management is important to increase the quality... 

In this thesis, the aim is to provide lower or upper bounds for the entropy of the geodesic flow on Riemannian manifolds. There are well-known results in this area derived from the works of mathematicians such as Sarnak, Osserman, Mane, and others. Our focus is primarily on geometric bounds that are expressed in terms of Riemannian curvature. We will attempt to examine these results in detail and consider some of their applications  

The present study looks into the fracture of perforated steel plates and their sensitivity in ductile fracture. It also examines the effects of strain rise phenomenon in these specimens. The main employed fracture model is VGM, which was first introduced by Rice and Tracey, and later enhanced by Kanvinde et al.. The general methodology includes finite element simulation and lab experiments on perforated plates, to determine ductility, strain concentration in hole periphery and model sensitivity. Fot thid purpose 86 steel sheet specimen with different holes and cuts were manufactured and tested. With the acquired data, the impact of strain concentration on the load carrying capabilities and...