Sharif Digital Repository

This project related to gas purification according to difference in the deposition point in the fludized bed.The reason for choosing fluidized bed is increasing erosion on wall of bed & increasing on heat transfer compared to other heat exchangers.Separation process, by cooling the wall causes the self- deposition gas phase shifts to solid phase. Solid formed on the wall, act as an insulating layer and greatly reduces the heat transfer therefore part of vessel not used. To solve this problem, the fluidized bed system is offered because the fluid particles can remove the insulating layer beside improving convection heat transfer coefficient. In this work we studied the quantative of erosion... 

Researchers show that one of the critical sources of bugs is API incorrect usage which in some cases can cause serious security vulnerabilities. The lack of knowledge about API correct usage rules is one of the main reasons that APIs are employed incorrectly by programmers, however, nding a correct usage rule for an API is time-consuming and error-prone particularly without having access to API documentation in most cases. Existing approaches to automatically extract correct usage rules, consider the majority usages as the correct rule for an API. Although statistically extracting API correct usage rules can achieve reasonable accuracy, it cannot work correctly in the absence of fair amount... 

Power transmission lines, which are responsible for the distribution and transmission of electrical energy from the power plant to the consumer areas, due to their characteristics such as long length and flexibility with low structural damping, face environmental irritations, especially the galloping phenomenon, causing many damages annually. In this study, it has been attempted to reduce the vibrations of power transmission lines by designing a robust active control and by using intermediate actuators in such a way that the failures of these lines can be prevented. For this purpose, linear modeling of the system and designing the controller using the pole replacement method have been done.... 

Increasing demand for Gold in electronic devices and catalysts, and its high cost, makes it crucial to recover the Gold from waste electronic devices such as Printed Circuit Boards. In this research, recovery of Gold by hydrometallurgical process based on heating the scraps along with a strong oxidizing agent, Potassium Persulphate, which is “eco-friendly” or “green”process is concerned. Recovery of Gold achieved by simple filtration process following by washing with water and nitric acid in order to dissolve impurities such as Al and Sn. The systematical and analytical evaluation method of Taguchi quality engineering has been applied for the leaching to evaluate the optimal experimental... 

Liquid-liquid extraction is one of the common chemical processes in the industry which its application is increasing day by day. Taking trend of increase of energy resources, chemical materials and industrial system into account, the necessity use of least energy consumption and material for achieving highest output and purity of products in different industries is attracted researches and industerialists.In this research we have studied the effect of presence of nano particles on both disperses and continuous liquids phases on hydrodynamic of deoplets specially their investigated system in this project was watter, toluene and acetone, and chosen nanoparticles wer carbon nanotubes and TiO2.... 

In this study, a tree-dimensional random pore-scale network model is used to simulate the membrane contactor porous medium. Drainage and imbibition phenomena is simulated to have a better knowledge of liquid and/gas intrusion trough the membrane porous structure. A genetic algorithm is used as an optimization tool. Several variables such as the number, radius and location of pores, the coordination number, as well as the radius and length of the throats are used herein as the optimization parameters. The difference between the binary SEM images and virtual sections on the generated network in conjunction with the permeability and mean pore size data were selected as the objective function.... 

Oil refineries, petrochemical factories and oil platforms produce a large amount of oily wastewater every day. If these wastewaters are released in environment, it can damage soil and water seriously. Although, Biological treatment of oily wastewaters is a well-established method for remediation of these wastes, efficiency of conventional systems such as Activated Sludge, aren’t very high. Also these systems have many problems such as instability during hydraulics shocks and bulking phenomena. the hybrid bioreactor system are designed to increase the efficiency of treatment by allowing greater organic loads, increasing microbial concentration by using attached and suspended bacteria, and... 

Radial turbines with small dimensions and in small power capacities are of great interest. In general, turbine performance improvement and higher output power may be achieved through increasing the inlet mass flow rates however at the expense of more weight and larger dimensions. On the other hand, increasing the inlet total temperature to the turbine will result in higher power potentials. Nevertheless, the turbine needs to be cooled in case that the intended inlet temperature goes beyond the turbine material limitation. In this thesis, radial turbine equations are reviewed and the logic of a 1D algorithm is developed where parameters like the total temperature, total pressure, and mass... 

The purpose of this project is estimating the two-or three-dimensional human condition using existing data(images or video). Human pose estimation can be used in applications، including the detection of human behavior، animation،human computer interaction، physical therapy and، etc . We use sparse representation method to estimating human pose In this project .Sparse representation methods in recent years has been used in many fields and probably in pose estimation can achieve good results with this method  

In the last few decades, the severe damages caused by near-field earthquakes have made researchers to investigate and study more of these types of earthquakes. The effect of forward directivity, which causes pulses with strong amplitude and long period in the velocity time history, is the main cause of severe damages of these types of earthquakes. The endurance time method is a dynamic analysis method in which the structure is subjected to increasing excitation functions. The purpose of this research is to investigate the effects of near-field earthquakes on structures and also to determine the accuracy of estimating responses caused by near-field earthquakes by the existing endurance time...