Sharif Digital Repository

An important step in the early stages of an oilfield development is the accurate identification of the location of production and injection wells which has a significant impact on productivity and profitability of the reservoir. Recently, operation companies in petroleum industry focus on production optimization, recovery enhancement and cost reduction; as a result, application of non-conventional wells (NCW) or non-vertical wells have dramatically increased. Well placement optimization is a complicated task as it is a function of several contributing factors including reservoir heterogeneities and economic constraints. The complexity of this task increases when it is considered as a... 

Intelligent control or management of well or reservoir is a method which is used in order to optimize the production for increasing recovery factor so that the minimum damage or reduction of pressure occurs during production lifetime. Azar oilfield has 17 wells and the production from this field isn't started. Thereupon designing a suitable well completion model and a control algorithm to optimize the production for the first two years of production is necessary and indispensable. For this purpose, by collecting basic information and their analysis (for example pressure, temperature, production rate, the type and amount of produced fluids), designing of downhole installations and modeling... 

Iran is one of the biggest suppliers of oil in the world. Iran's economy highly depends on its oil. Iran has valuable old reservoirs that need some techniques to optimize their production of it.Determining optimal well placement and control is essential to maximizing production from an oil field. The reservoir optimization problem is an extraordinary complex problem that depends on many factors such as flow pattern, well specification, reservoir properties, and environmental and economic criteria. Finding the locations of injection and production wells and other optimum operational parameters in the oil industry are very important and have a great influence on the operation of the... 

In this thesis, the process of laser assisted machining (LAM) of metal matrix composites (MMC) is experimentally studied. The effects of process parameters (cutting speed, feed rate and depth of cut), laser parameters (laser power, laser frequency and laser beam angle), and the percentage of reinforcing particles on the tool wear and the surface roughness are investigated. Furthermore, the effects of these parameters on the built-up edge (BUE), chip shape, and workpiece temperature are explored.The experiments were performed using uncoated tungsten carbide and PCD tools under dry conditions. In order to analyze the sensitivity of the process parameters, the Plackett-Burman method was used... 

Most motorcycles in developing countries use carburetor systems as the fuel delivery method especially for models with the cubic capacity of less than 150 cc. However, a small gasoline fuelled engines operating using carburetor system suffer from low operating efficiency, waste of fuel and produce a higher level of hazardous emissions to the environment. A retrofit fuel injection system (FIS) is a system that is developed to entirely replace the conventional carburetor system to improve its fuel economy and exhaust emissions providing a low-cost alternative in an effort to reduce fuel costs and air pollution. In this study, an electronic control unit (ECU) is designed for a fuel injection... 

The investigation of the behavior of structures subjected to various kinds of loadings is of considerable importance. In this research, an attempt was made to analyze behavior of beams that a load is moving on them.Most of the existing relevant works in this field are dealt with examination of elastic beams with constant section, while in most cases beams with variable sections are used in order to have the optimum structure and appropriate stress distribution and to maximize strength to weight or cost ratio. While construct analysis is very advantageous, it is very difficult due to the complexities arising from the variable sections. But this design is so advantageous that it dominates... 

This research focuses on the robust mobile robot localization exploiting motion information acquired from an optical mouse operating based on optical flow technology. Most techniques of visual motion measurement are based on the well research discipline called “optical flow”. Theoretically, optical flow as a method of localization can be highly accurate, but it is sensitive to the noise and surface texture/optical characteristics and distance variations between the CCD detector and surface. As one could not achieve acceptable results in practical situations, to handle these problems, we propose to attach an acceleration – gyro (INS) sensor on the CCD detector (optical mouse) to improve the... 

This thesis is presented to introduce a semi-active control of the suspension systems. The currently available semi-active damper technologies can be divided into two main groups. The first uses controllable electromagnetic valves and the second uses Magnetorheological (MR) fluid to control the damping characteristics of the system. A mass-spring model with eleven degrees of freedom, considering constant velocity for the car, is developed to model the suspension system. A semi-active vibration control system is presented to reduce the amplitude of automotive vibrations caused by the alteration of the road profile. The gravel road profile with Gaussian white noise as the road irregularity... 

Soft computing consists of a set of powerful methods that have been successfully applied to many different application domains, including business, engineering, and bioinformatics. In this research we propose an innovative approach that uses genetic algorithms to mine a set of behavior data output by a biological system in order to determine the kinetic parameters of the system. In our approach, the machine learning method is integrated with the framework of existent biological information in a wiring diagram so that its findings are expressed in a form of system dynamic behavior. An application of the method to the cell division cycle model has shown that the method can discover optimum... 

Wireless Sensor Networks (WSNs) consist of sensor nodes that are connected to each other and are widely used in many applications to acquire and process information. WSN nodes are battery powered, therefore energy management is a key factor for long live network. Node radio transceiver unit uses the most part of energy resource of the node and as a result limits the network lifetime. One way to prolong lifetime of network is to utilize routing protocols to manage energy consumption. To have an energy efficient protocol, we can apply cluster organization on the network, where sensor nodes are partitioned into groups called cluster. Then, the whole cluster data is sent through Cluster Head... 

Complex network studies grow by the scientific community, thanks to the increasing availability of real-world network data. The importance of using analysis on this type of network algorithms and community structure is one of the most important problems in the field of complex networks. Community Detection in a multidimensional network is still under investigation in the research community. The aim of this research is to give an algorithm for community discovery. We have reviewed the basis for multidimensional network analysis and will present a solid repertoire of basic concepts and analytical measures, which take into account the general structure of multidimensional networks. Then, we... 

The person identification by Electroencephalographic (EEG) signals has attracted the researchers’ great attention in recent years and lots of investigations have been developed. An identification system seeks to identify a person in a database. The advantage of using EEG signals for person identification is the difficulty in generating artificial signals for imposters. But more works need to be done to use EEG based biometric in real-life and this thesis is one of them. In this project we classify the EEG signals for person identification using AdaBoost algorithm. Adaptive boosting (AdaBoost) is a machine learning technique for pattern classification in which the performance of the weak... 

Determining the porosity, water saturation and permeability values in the reservoir rock, are major steps in the petroleum engineering and formation evaluation. Today in the oil industry, these parameters are obtained using Helium gas injection technique on core (Plug) samples. However, the coring operation is difficult and costly. In addition, there isn't the possibility of coring in some of wells, such as horizontal wells. In fact, the present research is the modelling of artificial neural networks to estimate permeability in one of the Iranian oil field reservoirs by using oil well logging data. In this research, MLP neural network has been used and for network training, the evolutionary... 

This thesis discusses a real-time vision-based framework for the purpose of hand region detection and hand gesture recognition. Our proposed methods include detecting hand regions in the cluttered background, based on Viola-Jones object detection algorithm and improving the classification of detected hand gestures regions in a novel contour-based framework. Our studies have demonstrated that deformability and high degree of freedom (DoF) of human hand as a non-rigid object besides diversity of skin color types, undeniable effect of cluttered background complexity, scalability and being robustness against rotation are the main reasons for considering some simplifications in visionbased... 

In process of making prosthetic limb, each of the prosthetic limbs must be costume fitted and built since each amputation of the patient is unique. The design and fabrication process of artificial limb consists of several different steps and begins with a precise measurement process that will be used to design the prosthetic limb. If possible, a prosthetist begins taking measurements before the patient's limb is even amputated, so that the fabrication process can get started. Today, much research which has been done in Augmented Reality and 3D scanning technologies shows that these technologies can help people with disabilities to have better experience in their life by using them in... 

In order to retrieve the temporal dynamics of the long term memory representation, which is believed that synaptically encoded with respect to an approach, we have utilized machine learning methods to classify the magnetoencephalogram (MEG) data that has been collected from an experiment called association task. The decoding process can be considered as a two-class classification problem in which we want to make a decision about the color or orientation of the grating of the test label. For the first step, different features have been extracted. This extraction can be done from the total signals of the different channels or can be extracted from the signal segments for each channel. These... 

This thesis proposes a novel method for enhancing the speech signal based on compressed sensing. Compressed sensing, as a new rapidly growing research field, promises to effectively recover a sparse signal at the rate of below Nyquist rate. This revolutionary technology strongly relies on the sparsity of the signal and incoherency between sensing basis and representation basis. Exact recovery of a sparse signal will be occurred in a situation that the signal of interest sensed randomly and the measurements are also taken based on sparsity level and log factor of the signal dimension.
In this research, compressed sensing method is proposed to reconstruct speech signal and for noise... 

Concerns like fuel cost, pollution and global warming has made it necessary to look for new energy solutions. Renewable and alternative energies have proven themselves to be helpful in this matter. Renewable energy(RE) is the energy that comes from natural resources such as sunlight, wind, rain, tides, waves and geothermal heat, which are naturally replenished at a constant rate. Renewable energies are environmentally friendly, not cheap at the beginning but naturally available in a constant rate and wide spread, unlike fossil fuels that are localized in the limited places. In this thesis in order to generate environmental friendly power we consider two renewable energy resources: wind and... 

The fire event may cause danger to life and property. In general, most fire-detection devices are set on the wall or ceiling. . However, this method is not flexible enough to detect a fire occurrence, and this needs the use of many fire-detection devices in a building. Since it is not suitable, we use an active fire-detection device to detect a fire incident. In the past, smoke sensors were used for fire detection, but often the smoke sensors triggered a false alarm when someone smoked in the room. Therefore, multisensor fire-detection methods are one of the current important developments for fire- detection technology. We design a fire-detection module using an ionization smoke sensor... 

Reliable communication has become very crucial in the transmission applications. Hence, to design hardware to handle reliability is the most important part of communication. In this work, we propose a new secured ALU (Arithmetic and Logic Unit) against fault attacks that is used in ARM processor which can correct any 5-bit error in any position of 32-bit input registers of ALU. We also designed a BCH (Bose, Chaudhuri, and Hocquenghem) codec (encoder, decoder) using the prototyping FPGA. Further, in this thesis we designed (63, 36) the BCH encoding and decoding system to tolerate the 5-bit faults. The codec system and ALU system are based on using Verilog description language. Since...