Sharif Digital Repository

In this research work, several guidance laws have been utilized and validated, considering the contraints on the missslie seeker angle and maximum acceleration, in order to simultaneously intercept the so-called Close-in Weapon System (CIWS) by multiple missiles. First of all, the existing guidance laws for salvo-attack are reveiwed. Then, a simulation program has been developed and validated for the misslie and CIWS as a five and two degrees of freedom systems, respectively. Optimization of the system is then carried out by the method of Particle Swarm Optimization, considering the given constraints. In the next step, for the improvement of the optimized guidance law, paramertic study has... 

Due to the undeniable importance and applicability of both "batch processing" and "parallel machines" in service and industry, this survey strives to solve a real-world problem in which some identical parallel machine, capable of processing jobs in batches, are available. In batch processing the process of jobs starts and ends simultaneously. In real world the processing time of the batch is a function of some characteristics of the jobs in the batch. in this survey, for simplicity (as calculating the mentioned function is so difficult), we assume that the processing time of a batch equals the sum of the processing time of the jobs in the batch. we also have assumed that the capacity of a... 

One of the most important required data in order to consult transportation studies is the amount of trip demand between different zones in the study region. Trip demand is usually presented in form of a table. Due to dependence of the demand on time, it gets classified in two categories: Static and Time dependent. In Time dependent problems, which the scope of this research is, trip demand is affected by network condition and the amount of traffic supply in short periods of time, e.g. 15 minutes. Using Traffic count and prior trip demand table in order to estimate the time dependent Trip demand is among the newest methods of travel demand estimation. In this research despite of older studies... 

One of the main concerns of automakers over last few decades was reducing fuel consumption while increasing the efficiency of vehicle. Using Continously variable transmission in vehicles could lead to reaching better performance, improving fuel consumption, reducing emissions and increasing vehicle acceleration. In this thesis types of Continously variable transmissions are introduced with focusing on steel V-belt CVT by analyzing its performance in steady and transient conditions. Unlike flat belts, V-belts moves both radial and tangential over the driver and driven pulleys resulting more complex dynamic.The dynamics of these systems in transient conditions are analyzed in two different... 

A well-designed Control Strategy (CS) in Hybrid Electric Vehicles (HEVs), as the manager of energy flow, reduces the fuel consumption and/or air pollution, while keeps an eye for prolonging the components lifetime. In this regard, the present thesis provides a new CS for parallel HEVs, based on emotional learning. It is noteworthy that the controller consists of a Takagi-Sugeno-Kang (TSK) fuzzy system and a critic. The driver’s torque command, State of Charge (SOC) error, Internal Combustion Engine (ICE) brake torque error and its time derivative constitute the controller inputs, while the output is the ICE torque command. The critic produces two stress signals based on HEV’s battery and ICE... 

With intensified concerns of rising fuel vehicles that reduce fossil fuel globally and also prescript strict rules by standard institutes, vehicle manufacturers try to find a way for reducing the fuel of their products. One these methods use a continuously variable transmission (CVT) instead of manual and automatic gearboxes. Various CVT’s have been proposed in recent year.
One of the proposed systems is traction infinitely variable transmission (TIVT) that is type of traction drive continuously variable transmission and has been presented in 2007. Research on this system showed that average efficiency is about 96% that is high efficiency. Completed research in 2011 showed that despite... 

This research deals with the problem of scheduling independent preemptive jobs on identical parallel machines, to minimize the total completion time (makespan). The transportation of an interrupted job from a machine to another machine requires considering a constant transportation delay i.e., Pm|prmp(delay)| Cmax. This delay is called transportation delay. We propose a Mixed Integer Linear Programming formulation for the research problem in case of two machines i.e., P2|prmp(delay)| Cmax. Since the research problem is shown to be NP-hard, a particle swarm optimization (PSO) algorithm is applied to solve the problem approximately. Based on the frequency of using local search procedure, three... 

Image Registration is a fundamental task in numerous applications in medical image processing and is defined as the process of determining the correspondence of between images collected at different times or using different imaging modalities. This correspondence can be used for aligning images so that the pair can be directly compared, combined or analyzed. Image-guided surgery systems use registration for establishing an accurate relation between preoperative and intraoperative image space. There have been several methods for rigid registration which are not easily applicable for soft tissues. Indeed, nonrigid deformation of soft tissues will endanger the accuracy of rigid methods, so it... 

This PhD dissertation presents the chemometric techniques as a tool to obtain maximum information from the chemical and biological systems. In this regards, two objectives have been followed. The first objective was to apply the design of experiment methods for approaching the most reliable data. In this section, the main concepts and applications of experimental design approaches to optimize the common analytical chemistry techniques are reviewed. The critical steps and tools for screening including Plackett-Burman, full factorial- and fractional factorial designs and response surface methodology such as central composite, Box-Behnken and Doehlert designs are discussed. Descriptions of... 

The aim of this project was to design, analyze and fabricate a 4 DOF robotic arm to be used as a slave robot for tool handling in laparoscopic surgery. The mechanism used for this purpose should have a remote center of motion in order to be able to manipulate the tool through the small incision point. The robot should also provide sufficient force to handle endoscopic tools used for large organ manipulation and be capable of measuring these forces. A variety of mechanisms were studied thoroughly, and the best solution was chosen by considering the design parameters such as workspace, manipulability, accuracy, ease of fabrication, etc. The final design consists of a 2 DOF serial spherical... 

Although many mathematicians have searched on fractional calculus since many years ago, but its application in engineering, especially in modeling and control, does not have many antecedents. Because there are much freedom in choosing the order of differentiator and integrator in fractional calculus, it is possible to model the physical systems accurately. Also, there is the same reasoning in the control area. We can design such fractional controllers that have high performance. Among the fractional order controllers, the fractional order PID (FOPID) has been dealt with more than others and there are many methods to design it, such as Ziegler-Nichols, state space and method based on genetic... 

Classification of Traffic Internet obtained early interest in the computer science community. Various methods have been presented for classifying the traffic of Internet to manage both security and Quality of Service (QoS). Nonetheless, traditional methods of classification including scheme of Transmission Control Protocol/Internet Protocol (TCP/IP) have not been accepted because of their complicated management. Classification method of network through learning algorithms of machine is the most popular classification method of traffic at this time. ELM was proposed as a modern algorithm of learning for the Single-hidden Layer Feed Forward Neural Networks (SLFNs). Meanwhile, learning process...