Sharif Digital Repository

Varian Clinac 2100 accelerator head was simulated using EGS5 Monte Carlo code. Phase space method was applied to this simulation. Two phase space plates were used in these simulations; one was inserted before the moveable jaws and the other one was placed after the jaws. The first plate was simulated for energy. And the second plate was to simulate each field size at the set energy. In the phase space method used in the EGS5 code one extracts the particle parametric information from a file as opposed to following the original particles that start at the source point. It is expected that this file to be a replica of the particles that pass the plate and further it should not add any... 

Beam diagnostics is an essential constituent of any accelerator. The position information of the electron beam is obtained by a set of Beam Position Monitors (BPMs), which in addition to determining the position, are used to derive information concerning lattice functions and beam dynamics. To design of Button Beam Position Monitor(BPM) for a Synchrotron Light Source, to get beam stabilities on submicron levels, preliminary studies were done to have optimal design. We present an algorithem which caculate all required parameteres for different design of button BPMs. To calculate induced charge and voltage on each button, Poisson's equation has been solved by Green method. For sensivity... 

Designing a system based on 2 to 5 MeV electron accelerators for X radiation of urban waste.Nowadays , the use of ionizing radiation in two cases of treatment and removal of contaminants in the waste including; 1) Pathological hospital waste 2) leachate from buried urban waste, which is studied and examined in this project. Buried urban wastes begin to break down under aerobic and anaerobic processes, and as long as the materials are not changed into sustainable materials, these processes will continue and results in landfill gas and leachate. Gas is produce due to anaerobic processes and leachate which is produced through water infiltration (atmospheric precipitation) in the landfill or... 

Using accelerators inside high speed servers can reduce execution time of applications and total power usage of the system. Sharing accelerator between virtual machines of a server decrease both cost and power, however it won’t provide the gained speedup of using dedicated accelerator for each virtual machines. Creation of an appropriate set of accelerators required for virtual machines, management of accesses to the accelerator, prioritizing and scheduling of requests and reconfiguration type of accelerator are the most important challenges that this project has been dealt with. The main objective of this project is implementing the necessary infrastructure to share an FPGA-based... 

Due to the data centers rapid growth and introduction of a new basic type of massive data processing platforms which requires accelerators to speedup computation and enhance the efficiency and reduce power consumption, using accelerators is inevitable. Communication and data transfer time between software and hardware is the most of time spent on the use of accelerators. By optimizing this part of the hardware / software platform, we have achieved substantial results in this area. The aim of our study is to organize a survey of real accelerator characteristics. To figure out its defects and main drawbacks, in addition to improving the overall efficiency of system. The implementation of... 

With the proliferation of data centers, their ever-growing energy consumption has gained lots of attention from both academy and industry . Two primary parts that use majority of energy in data centers are IT equipment and cooling system or Computing Room Air Conditioning (CRAC) unit. Energy consumption of cooling system strongly relies on thermal performance of data center. Therefore, applying thermal management techniques for decreasing energy consumption of CRAC is a common practice. Moreover, the energy consumption of IT equipment affects the energy consumption of CRAC directly. Demand for more computing resources in data centers and their physical limits has, motivated the use of FPGAs ... 

As accelerators develop, literature about their distinctive characteristics and functions grow. Primary studies about business accelerators focused on defining the model and finding the distinctive characteristics of business accelerators. Later studies started to ask different kind of questions about outcome, functions and especially different models of accelerators. . Accelerators in developing countries are new phenomenon. Considering the fact that economic and entrepreneurial ecosystem are different in developing countries, accelerators in these countries have some distinctive characteristics which are not studied deeply in small accelerators literature.Employing Pauwels’ design elements... 

In recent years, big data processing plays an important role in the era of information technology. The exponential growth of big data volume increases the need for data centers and infrastructures with more processing power. Due to dark silicon and scalability limitations in deep-submicron, the increasing trend of server performance slows down. Therefore, hardware accelerators such as FPGA and GPU are become increasingly popular for improvement of data center processing power. There are two types of big data processing based on the application: stream processing and batch processing. With the widespread use of social networks, online control systems and internet of things services, the... 

Distributed stream processing frameworks (DSPFs) are used for real-time processing of big data. Apache Storm is one of the most popular stream processing systems in industry today. By increasing data generation rate we need new methods to overcome processing requirements of DSPFs like Apache Storm. In this thesis we investigate the feasibility of incorporation FPGA acceleration into Apache Storm. Using FPGAs as co-processors in powerful servers can improve performance and accelerate processing of streaming data by increasing parallelism, decreasing processing time of each processing units and decreasing communication delay between these units. Our design includes a hardware part that... 

The aim of this thesis is to investigate one of the novel methods of accelerating particles such as electrons acceleration method. In intense femtosecond laser plasma interaction, a Wakefield is formed that trap electrons and accelerating them which this process will be fully addressed in this project. Due to the recent rapid development of technology for producing over dense plasma in laser-plasma interaction process in smaller sizes and the possibility of nuclear fusion reactions, the quantum effects are important and must be taken into account quantum effects in plasma. We study quantum effects by introducing the Bohmpotential and assuming the plasma as a one dimensional electron fermi... 

In order to adjust the electrons beam in microwave lamps, an accurate electromagnetic field that is produced by a solenoid is required. The precision of the magnetic field generated by this solenoid is very important, and in advanced systems this precision is less than 10 ppm. This system is used to adjust the radiation rate for producing a variety of radiopharmaceutical. The major problem of the system is that the electron beam changes by time due to a change in the magnetic field, and this event causes the operator's room to be radiated. Constant calibration of this system is also very demanding and impractical. An example of these highly accurate (several ppm) systems are used in the... 

Elastomers are flexible polymers with various uses in different industries. But this materials dont havevalid usages without correct fillers. Today Nano technology has a main role in the industry. one of the important reasons is rubber quality improvement with adding just a little amount of this clays, opposite to Carbon Black. To achieve a high quality polymer composite, it is necessary to learn about physical and mechanical properties of nano clays and the interaction between Nano clays and matrix. Because of the effect of nano clays on vulcanization, this issue is noticeable . Nano diamond is a nanoclay used to improve rubber quality. But this method is new because of the complicated... 

The ever-increasing volume of data and calculations has caused a noticeable increase in the importance of computer processing speed. Therefore, topics related to parallel processing as an effective solution in increasing the speed of calculations have been specially investigated and studied. Systolic computing is a powerful approach to parallelize data and perform concurrent computations. Systolic arrays fulfill the goals of the algorithm by directing data flow among different processors and performing minor calculations on them. The slowness and limitations of processors compatible with these arrays, such as FPGAs, have faced many challenges in applying and using their capacities. These... 

Recently, Convolutional neural networks (CNNs) are widely used in many artificial intelligence applications such as image processing, speech processing and robotics. The neural networks superior accuracy comes at the cost of high computational complexity. Recent studies show that these operations can be performed in parallel. Therefore, as graphic processing units (GPUs) offer the best performance in terms of computational power and throughput, they are widely used to implement and accelerate neural networks. Nevertheless, the high price and power consumption of these processors have resulted in drawing more attraction towards Field-Programmable Arrays (FPGAs). In order to improve resource...