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Factorial-Based Analysis and QSXR Studies of Components of Essential Oils and Environmental Pollutants
, Ph.D. Dissertation Sharif University of Technology ; Jalali Heravi, Mahdi (Supervisor)
Abstract
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...
Bus Routing on Printed Circuit Boards
, M.Sc. Thesis Sharif University of Technology ; Zarrabi Zadeh, Hamid (Supervisor)
Abstract
recent years, by the huge increase in the number of components on a board, the bus routing problem and minimizing the number of layers of a board has emerged as a significant challenge in designing Printed Circuit Boards (PCBs). Two related theoretical problems to bus routing are the Rectangle Escape Problem (REP) and the maximum independent set of rectangles problem where both of these problems are NP-hard in the general form. In this thesis we study some variants of these problems and try to improve the running time or approximation factor of the best algorithms previously provided for solving them. The maximum disjoint set of boundary rectangles problem is a variant of the maximum...
Route Planning for Tourists Based on Online Information
, M.Sc. Thesis Sharif University of Technology ; Akbari Jokar, Mohammad Reza (Supervisor)
Abstract
Because of some limitations, tourists can not visit all the attractions during their one or multiple-day trip. So, they need to select the best places worth to visit based on information that they gathered via the internet, magazines, tour guides, etc. Also, they should choose the best route to the selected place, considering its visiting time and ways conditions. Other factors such as visiting days/hours and the timetable for a place, entrance fees and the other limitations should be considered simultaneously. These requirements and questions are all discussed as a tourist tour plan problem in the field of operations research. In this research, different kinds of tour planning problems have...
The Bi-objective Capacitated Facility Location-Network Design Problem with Multi-type of Links and Facilities
, M.Sc. Thesis Sharif University of Technology ; Eshghi, Kourosh (Supervisor)
Abstract
One of the primary concerns on many traditional capacitated facility location-network design problems is to consider costs of transportation and establishing of facilities in one single objective function. Considering a single objective in these problems may lead to misleading solutions due to the fact that the transportation costs should be considered in a short-term period of time, and therefore, the higher cost of establishing the facilities may unfairly dilute the role of the transportation cost. In this thesis, we introduce the capacitated facility location-network design problem with two separate objective functions. Moreover, in this problem, it is assumed that for connecting two...
Inverse Problem Of Pyroshock Simulation Apparatus
, M.Sc. Thesis Sharif University of Technology ; Saadat Foumani, Mahmood (Supervisor)
Abstract
One of the important experiments on satellites and their components is testing of their resistance to shock wave known to pyroshock. Pyroshock is transient response of a structure to a high frequency and high acceleration shock wave that is created by the action of a member of pyrotechnics in the satellite structure. This research is for design, construction and calibration of a pyroshock simulator apparatus which is done with specific requirements and aims. For this purpose, in first step an experimental test is done and validation of computer simulation is obtained by using results of test. By use of computer simulation tool, new design is presented. After constructing the apparatus and...
Ekranoplan Design Survey, Determination and Enhancement of Flying Qualities characteristics Through Stability Alalysis
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
During the last five decades, interest in High Speed Marine Vehicleshas been increasing for both commercial and military use, leading to newconfgurations and further development of already existing configurations to fill the gap between the low speed ships by high payload capacity to low construction cost, and high speed aircrafts by low payload capacity to high construction cost. Therfore Wing-In-Ground effect crafts (WIG)were introduced as the new marine vehicles family memberwhich have the potential for payload capacities closer to fast marine crafts and the cost of construction is much lower than aircraftswhile they are capablefly close to the water surface. On the whole, in this...
Management and Efficient Allocation of Resources in Competitive Networks
, Ph.D. Dissertation Sharif University of Technology ; Golestani, Jamaloddin (Supervisor)
Abstract
In contrast to traditional Networks where a designer can specify an action plan for each agent, in a network with strategic agents, every agent acts selfishly and chooses his strategy privately so as to maximize his own objective. In this dissertation, we study problems arising in the design of static and dynamic networks with strategic agents. We consider two classes of design problems. In the first class, the designer utilizes her control over decisions and resources in the system to incentivize the agents via monetary incentive mechanisms to reveal their private information that is crucial for the efficient operation of the system. In this class of problems, we address two main challenges...
Fruits and Vegetables Supply Chain Management (Case Study: Kerman Province)
, M.Sc. Thesis Sharif University of Technology ; Akbari Jokar, Mohammad Reza (Supervisor)
Abstract
One of the challenges of today's economy, is improving economic structures and reduce its dependence on oil revenues. Agricultural industry as an important part of the economy, is not dependent on oil revenues and improving its structure can have a significant impact on increasing revenues. Kerman province with a high proportion of horticultural products in the country, plays a significant role in Agricultural industry .However, the problem of water shortages in the country, highlighted the efficient use of water in economic purpose and crop-planning. By the problems with the current structure, lack of management of planting crops, lack of proper supply chain, redesign of agricultural supply...
Power Management Reliability-aware in Mixed-criticality Embedded Systems
, M.Sc. Thesis Sharif University of Technology ; Ejlali, Alireza (Supervisor)
Abstract
Mixed-Criticality Systems (MCSs) include tasks that have multiple levels of criticality and they operate in dierent modes. These systems bring benets such as energy and resource cost saving. However, there are challenges in how to manage available resources in order to achieve high utilization, low power consumption, and required reliability. In many cases, these goals are in conict with each other. For example, if ermal Design Power (TDP) was a constraint on the power consumption of the chip, an approach that increases the utilization, unaware of power consumption, can oversteps TDP and leads to permanent or transient faults. Hence aging balancing and task re-execution are utilized to...
Peak Power Management in Fault-tolerant Embedded Systems
, M.Sc. Thesis Sharif University of Technology ; Ejlali, Alireza (Supervisor)
Abstract
Technology scaling allows integrating multiple cores onto a single chip to make the mainstream for advanced embedded systems. However, technology scaling is envisaged to aggravate the reliability of on-chip systems due to increasing transient fault rate due to lower voltages and shrinking transistor dimensions that lead to smaller critical charges. Transient faults are typically resulted due to high-energy particle strikes in hardware and manifest as bit flips. Multi-core systems provide a great opportunity to implement reliability mechanisms such as redundant multithreading (RMT) and process level redundancy. Task replication (e.g. RMT) is a well-established technique to achieve high...
Energy Management through Topology Optimization of Microstructure of Tow Phase Functionally Graded Materials (FGMs) under Dynamic Loading
, M.Sc. Thesis Sharif University of Technology ; Bagheri, Reza (Supervisor) ; Tavakoli, Rouhollah (Co-Advisor)
Abstract
A numerical algorithm is proposed to design microstructure of a two-phase functionally graded material under dynamic loading. In order to direct energy propagation through the desired regions in the domain, we introduced a regularized Heaviside function, H(x), in our objective functional, namely the time-averaged sum of the elastic strain energy and the kinetic energy. Real-life systems are however, not undamped, but possess some kind of energy dissipation mechanism or damping. In order to apply modal analysis of undamped systems to damped systems, we use Rayleigh damping model in our formulations. To generate a well-posed topology optimization, we used homogenization via a solid isotropic...
Management of System Requirements in Systems Engineering Process with Axiomatic Design Principles
, M.Sc. Thesis Sharif University of Technology ; Malaek, Mohammad Bagher (Supervisor)
Abstract
Functional Requirements (FR) are traditionally known to be "input" as far as an engineering process is concerned. However, for a Systems Engineer (SE), this is not the case. A well-known task of a SE is, in fact, to develop FRs from what is considered as the customer needs. The traditional approach to develop suitable FRs involves an algorithmic procedure; which mostly relies on the skills, knowledge, attitude, and experiences of the SE or experts members of design team. It is therefore an ad-hoc method which results in quite a few numbers of trial-errors and its effectiveness only reveals itself as time goes on. The current work aims to address such a shortcoming in Systems Engineering...
A Model For Flight Frequency Determination and Aircraft Routing
, M.Sc. Thesis Sharif University of Technology ; Shafahi, Yusof (Supervisor)
Abstract
In this research a model is proposed which determines flight frequency and aircraft routing for an airline network. It is supposed that origin-destination demand, costs, number of aircrafts in the fleet and their capacity, aircraft maximum daily utilization hours and origin-destination fares are given. The model attempts to maximize airline profit and determines flight frequencies, number of passengers carried between two cities and number of passengers who travel with an indirect flight, considering fleet constraints and an operational aircraft routing.The model is tested with a hypothetical numerical example. The results indicate that the model uses maximum aircraft capacity and daily...
Feeder Network Design for Rapid Transit System
, M.Sc. Thesis Sharif University of Technology ; Shafahi, Yusef (Supervisor)
Abstract
Encouraging passengers in order to use public transportation facilities is one of the goals of transportation planners. The most effective way to increase the market share of public transportation is enhancing its Level of Service via faster and more comfortable transportation in comparison with private vehicles. Exploitation of rapid transportation lines (Subway, BRT, and etc.) is justifiable in corridors in which the demand exceeds a minimum value. While in most of metropolitans such demand may not be present inadvertently in any of corridors, generating the needed demand and increasing the accessibility to public transportation is possible using feeder lines like feeder buses. In fact,...
Dynamic System Optimal Design Model: Designing and Evaluation of Turboexpander System Operation
, Ph.D. Dissertation Sharif University of Technology ; Saboohi, Yadoolah (Supervisor)
Abstract
According to Iran’s energy policies, the natural gas transmission pipeline has expanded significantly over the last decade. Moreover, improving energy efficiency is known as a key strategy in energy policies and programs. Therefore, the need for expansion and development of the rational use of energy has received more and more attention. The use of technologies aimed at energy recovery will be an effective step in this regard. Pressure regulators are most commonly used to reduce this pressure in Iran as one of the significant sources of exergy destruction in Iranian gas transmission system. The turbo-expander system is a kind of technology applied in gas pressure reduction stations to...
One Dimensional Numerical Simulation of Gas Exchange and Combustion Processes in a Port Fuel Injected Gasoline Engine to Optimize Intake Valve Lift, Timing, and Duration
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Vahid (Supervisor) ; Mozaffari, Ali Asghar (Co-Advisor)
Abstract
In the modern world, one of the largest concerns is the ever depleting supply of oil. The automotive industry is especially impacted. In recent years the price of gasoline has fluctuated substantially and the price of crude oil has reached record highs. The high price of gasoline coupled with the uncertainty of its availability and future price have put a high priority on fuel economy of an engine. In addition the emissions released from internal combustion (IC) engines are polluting the atmosphere. Many studies have linked the greenhouse gases produced by an automobile engine to the partial destruction of our atmosphere and to global warming. As a result the US government is passing...
Modeling of Walking in a Gait Trainer, to Modify and Optimize Its Mechanism
, M.Sc. Thesis Sharif University of Technology ; Farahmand, Farzam (Supervisor) ; Narimani, Roya (Supervisor)
Abstract
Several diseases and injuries may cause disability in locomotion (especially walking). Spinal cord injuries, brain stroke and disease like Parkinson are the most major causes. In the past, some efforts has been made to reduce the effect of organ’s disabilities, but today, there is the chance of healing the spinal cord injury By using new (Schwann Cell) method. Due to long time stillness and severe muscles weakness; condensed physiotherapy exercise is essential to recover locomotion abilities, particularly in walking. In this way, if the practices matches with the normal walking (especially weight bearing); it has more physiological and psychological effect. In order to achieve this goal, a...
Nonlinear Microwave Circuits Design and Modeling using Behavioral Models Based on Volterra Series and X-parameter
, Ph.D. Dissertation Sharif University of Technology ; Banai, Ali (Supervisor)
Abstract
Modern microwave and wireless communications systems are too complex today to permit the complete simulation of the nonlinear behavior at the transistor level of description. This problem presents a significant productivity bottleneck for design engineers. At the bridge between the transistor circuit and the multichip module or RF integrated circuit (RFIC) we use “behavioral models” to describe the nonlinear circuit blocks or ICs in the system. The behavioral models are simplified models of the essential nonlinear behavior of the complex sub-circuits; this simplification means that these models will execute more quickly, and use much less memory than if an entire complex subsystem was...
Modeling and Design of CCHP System for Sharif Energy Research Institute
, M.Sc. Thesis Sharif University of Technology ; Sabbohi, Yadollah (Supervisor)
Abstract
The aim of the present research project has been techno-economical analysis of using a CCHP (Combined Cooling Heating and Power) technology at the building of Sharif Energy Research Institute (SERI). The CCHP at SERI is supposed to supply energy required at the building. Useful energy demand at the building include heating in winter, cooling and air conditioning in summer, lighting and power requirement of electric appliance and equipments. Since there are many technologies that could be utilized as CCHP, an optimal model of energy supply system of the building has been developed in order to identify the most appropriate technology. The application of model has enabled techno logical...
Modeling and Optimal Design of a Solar Chimney Power Plant
, M.Sc. Thesis Sharif University of Technology ; Boroushaki, Mehrdad (Supervisor)
Abstract
The power generation system of this type of power plants operates on the air flowing through the power plant’s chimney and colliding with the turbine blades within the chimney. When the solar collector warms the nearby air and thus expands the air by absorbing the sunlight, a difference is created in the density. Then, this difference in the density creates the phenomenon of buoyancy, making the air pass to the top of the chimney through the collector.This study simulated and optimized a solar chimney power plant. The simulation and optimization were performed based on the information of Manzanares Solar Chimney Power Plant in Spain (located in 150 km from the south of Madrid). It was...