Cost Effective and Optimum Strategy for Gride Connected Small Wind Turbine

, M.Sc. Thesis Sharif University of Technology Hajbabaei, Amirhosein (Author) ; Oraei, Hashem (Supervisor)

Abstract

Regarding the range of power in small wind turbine ,the manufacturing cost is very important to produce it feasible . so cost factors should be considered in control strategy. small wind turbine operate at lower wind speed because they are located where the energy is needed rather than where the wind is high for example in residential or rural area in lower height. In these condition wind speed are changing more because of lower height .so the maximum power point tracking algorithm should have a fast dynamic. In order to have lower number of device there are no sensor for wind or generator’s speed .only the voltage and current of different part of the system is measured.
here the aim...

Robust Face Verification under Occlusion in Video

, M.Sc. Thesis Sharif University of Technology Hajbabaei, Mohammad Reza (Author) ; Ghaemmaghami, Shahrokh (Supervisor)

Abstract

Nowadays, using of digital cameras is streaming across the world dramatically. Application of these devices is very diverse. One of the most interesting application of those is face verification. For example, imagine your smartphone has an application which verifies faces in front of its front camera, if that face be your face (with variation from original) then application automatically unlocks your phone. Face verification systems are also deployed in airports to verify passport photos and in smart homes. One of the most regular problems in face verification is occlusion. When your face is occluded with natural or random changes we can say your face is occluded. All of the recent papers...

Spot Resistance Welding of St12 and HSLA Steels in Different Thicknesses

, M.Sc. Thesis Sharif University of Technology Farhangdoust, Sajad (Author) ; Kokabi, Amirhosein (Supervisor) ; Ekrami, Aliakbar (Supervisor)

Abstract

High-strength low alloy (HSLA) E275 developed specifically for automotive application. Also St12 Steel is used in autobodies. On the other hand the resistance spot weld of dissimilar materials is generally more challenging than that of similar materials due to differences in the physical, chemical and mechanical properties of the base metals. The influence of the primary welding parameters affecting the heat input such as; current and time on the morphology, fracture mode, microhardness, and tensile shear load bearing capacity of dissimilar welds between HSLA E275 steel and St12 steel in two different thicknesses (1,2 mm) has been investigated in this study which consisted six group. The...

Design and implementation of current based vector control model of brushless doubly fed induction generator

, Article 2013 3rd International Conference on Electric Power and Energy Conversion Systems, EPECS 2013 2013, Article number 6713022 ; 2013 ; 9781479906888 (ISBN) Moghaddam, F. K ; Gorginpour, H ; Hajbabaei, A ; Ouni, S ; Oraee, H ; Sharif University of Technology

2013

Abstract

This paper is aimed at proposing a current based vector control model of the brushless doubly fed induction generator, modelling the presented control method, as well as implementing the proposed algorithm by DSP. In order to achieve the purpose, by presenting a detailed coupled circuit model of BDFIG, the vector model and then the current based vector control algorithm of the mentioned machine are acquired. The way of independent control of torque and power, and also the structure of speed controller amongst the proposed control model are discussed. Additionally, the concepts behind the proposed structure of the speed control system and the way of determining the model parameters are...

Security Enhancement Wireless Body Sensor Networks

, M.Sc. Thesis Sharif University of Technology Yavari, Nafiseh (Author) ; Jahangir, Amirhosein (Supervisor) ; Nazarishirejini, Ali Asghar (Supervisor)

Abstract

The use of wearable surveillance systems and wireless body sensor networks is an economical solution to medical care, which is capable of detecting abnormal conditions early, and by controlling the health status and enabling one to engage in normal and daily activities, improves the patient's quality of life. Information and communication security is very important in this area and its violation may even endanger the life of the patient. The selection and application of the appropriate security mechanism for a wireless body sensor network is subject to consider the requirements and limitations of the network. One of the most important security requirements in this area is the...