Sharif Digital Repository

With respect to the introduction of bio-material into cells (transfection) , microinjection is a highly efficient technique amongst existing methodologies. In cell injection, a manipulator injects the needle into a cellwhich is hold by a pipet mechanism. The moving range for the needle in this operation is of centimeter order and the resolution for the needle tip should be less than the cell’s diameter. In this thesis a Stewart system is used as for the manipulator. Stewart systems are used in flight simulators systems for decades, as mechanisms which are capable of providing multi-axis movements. In high accuracy positioning and multi-axis applications Stewart systems are highly reliable.... 

The purpose of this thesis is designing and implementation of a Carry Skip Adder using CMOS traditional technology and Gate Diffusion Input technique (GDI). I present a carry skip adder (CSKA) structure that has a higher speed, lower energy consumption compared with the conventional one. The Gate Diffusion Input is a novel technique for low power digital circuit design. This technique reduces the power dissipation, propagation delay, area of digital circuits and it maintains low complexity of logic design  

In this study, the effect of the Cu interlayer thickness was studied on St52 steel. Specimens with different thickness of the interlayer, were subjected to 1150 °C at different times. Isothermal solidification was completed for the thickness of the 50 μm, 30 μm, and 10 μm in 30, 25 and 20 minutes. Afterwards, homogenizing and dual-phase heat treatment were used for 75 minutes at 730°C. Optical microscopy and SEM were used to analyze the microstructure of the joints. Mechanical properties of the joints, including micro hardness of different parts of the joint and also shear strength of the joint zone were studied. The results show that after homogenizing treatment, microstructure and harness... 

Software product line (SPL) engineering offers several advantages such as reduced costs, high quality and less time to market in development of family of software products. The goal of software product line is systematic and effective development of a set of software products which share common and managed set of features. Software product line testing has its special challenges such as scalability and variability, and has significant importance due to the importance of quality in software product line and enormous number of possible products. Most of the popular methods in this domain have shortcomings such as having seam between development and testing processes, limited application scope... 

The increasing demand for air transportation, along with air traffic limitations and environmental pollution concerns, necessitate a comprehensive study in the field of airspace-management. In this regard, one of the promising alternatives is flying smarter via “Formations”. In fact, many works have discussed the benefits of “Commercial Formation Flights”; however, none have discussed a practical way to manage such formations for long-distance cruise. This paper discusses a new approach to manage the “Geometrical Arrangement” of such flights in an efficient manner. In fact, with the help of the so called “Game Theory” and without complex computations we are able to guide each individual... 

The purpose of this study was aimed to evaluate the effect of Alumina on the sintering, phase development, mechanical properties and biocompatibility of fluoridated hyroxyapatite sintered via conventional furnace and microwave assisted oven. Green compacts having 30wt% Alumina nanoparticles were sintered without pressure at various temperatures (1000-1400°C) for one hour in conventional furnace. Phase composition, thermal behavior and morphological analyses were performed using X-ray diffraction (XRD), simultaneous thermogravimetry and differential thermal analysis (STA), and Scanning Electron Microscopy (SEM), respectively. With the increase in temperature and the Alumina content, severe... 

Regarding the ever-increasing usage of text generation and analysis in Natural Language Processing field, Language Modeling and Masked Language Modeling have been recently one of the most frequent tasks. Besides, many pretrained models such as BERT have been proposed due to the lack of rich datasets and computational resources among researchers. These models can be finetuned on other datasets in downstream tasks. Although these Transformer-based deep neural networks have performed perfectly in many problems, they still have some shortcomings in a few tasks.Furthermore, structured data like graphs have been recently used extensively in Natural Language Processing and researchers have taken...