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In this thesis, we have studied some exact solutions for low dimensional strongly correlated systems, especially spin chains. In the first chapter using simple AKLT model and introducing Valence Bond Solid States we have prepared good area to study Finitely Correlated States. In addition to presenting relation between these concepts, we have expressed Matrix Product States as a simpler formalism to deal with Finitely Correlated States. In the second chapter we have discussed the Optimum Ground State concept and we have studied a spin-32 with nearest neighbor interaction and a spin-1 model with next nearest neighbor interaction
as example  

The present research illustrates the Effects of Stiffness Distribution on Demand Reduction in Elastic Multi Degree Freedom Structures. The structural configuration of a structure has an important effect on dynamic performance of it and its nonstructural contents. For equipment, the displacement or acceleration demand is defined in terms of the input motion applied at the appropriate attachment point(s) of the equipment. This demand or input motion is generally represented by an in-structure response spectrum (IRS). The IRS will differ significantly from the design base earthquake (DBE) spectrum because it is essentially filtered and/or amplified through the building. To assess the realistic... 

The membrane bioreactor (MBR) as an alternative method for simultaneous biodegradation and separation of oily water has received more attention, recently. Normally the MBR works at ambient temperature; therefore, the yield of biodegradation recalcitrant components is low. Increasing temperature improves the efficiency of degradation and reduces the amount of produced sludge. In this study the performance of an aerobic thermophilic and mesophilic membrane bioreactor (MBR) for treating oily wastewater has been investigated. In batch conditions (without applying the membrane), a comparison between COD removal in mesophilic and thermophilic conditions was done. In thermophilic conditions COD and... 

Design of complex systems requires different challenges to be met simultaneously. Yet the current methods lack a sound theoretic framework and thus designers normally rely on heuristic or empirical methods; based on available experiences. Such approaches to the system design entail both technical and business risks and subsequently increase the probability of long-term problems. In this research, along with the theoretical framework of the systems design concepts, we discuss number of important models. The main concentration of the work, however, is to; somehow, correlate Axiomatic Design Matrix (ADM) with Design Structure Matrix (DSM). Here we exploit mathematical model based on sets and by... 

CDMA is one of the main multiple access techniques. In this thesis, we study the channel capacity and the optimum codes for CDMA systems under different conditions. The optimality has different meaning for each studied scenario. The discussed scenarios differ from the aspects of the alphabet of the system, the ability of getting active or inactive for users, and the random fluctuation of the user powers. The first scenario is the systems with real input alphabet. In this case, by optimum codes, we mean a code that maximizes the sum channel capacity of the system. The second scenario is the systems with binary input alphabets and binary signatures. In this section, optimum codes are the codes... 

Synthesis gas to light olefin reactions especially propylene production is one of the important path for clean fuel production in gas conversion processes. The object of this study is to define true kinetic model of process first step (e.g. Synthesis gas to light Olefins). For that, kinetic model for Co/Mn/TiO2 catalyst, which has the best conversion and selectivity for propylene, has been developed. Kinetic reaction parameters were measured by kinetic modeling in (220-300)0C temperature , (1-5)bar pressure , H2/CO=(1:3) and (450-600)hr-1 space velocity .After studying with significant models ,the best fitting can obtained with "KPCO P 1/2H2/(1+aPco+bPH2 1/2)2"equation. Later to... 

Structural changes in the energy sector, including the need to diversify sources of energy supply, security of supply, energy consumption growth in developing countries, rising oil prices and the exhaustibility of fossil fuel reserves, environmental issues, increased consumption of petrochemical products etc., has led to increased share of natural gas in primary energy supply. Iran has a wide range of options to use natural gas endowment. The present research aims to develop a model for optimal allocation of natural gas to various applications.The gas distribution system is modeled in the present study. Technical onstraints together with economic characteristics are considered in the model.... 

There are different well-established strategies for making a process plant inherently safer. The benefits of applying these strategies on reducing the overall risk inside a plant are obvious. However, some of these changes are rejected many times because they appear to be too costly. But if the effects of applying inherently safer design strategies are investigated not only on the processing costs of a plant but also on the potential accident costs, the decision would in fact be different. In this paper an optimization procedure is proposed which integrates both processing and accident costs for different design schemes. In this procedure, some of the design variables are chosen with regard... 

Soil nailing is a method of in situ reinforcement utilizing passive inclusions. It can be used to retain excavations and stabilize slopes by creating in situ, reinforced, soil retaining structures. This method has been used widely in recent years. Construction of a soil nail wall is performed in vertical steps, with construction starting at the top of the excavation and proceeding down. Once an excavated step is reinforced with soil nails, a permanent or temporary facing is then applied to retain the soil. Stepped soil nail wall is formed by setting a platform in the middle part of a typical soil nail wall.In this Thesis, behavior of a soil nail wall and a stepped soil nail wall are studied... 

On one hand Code Devision Multiple Access (CDMA) as an efficient spread spectrum multiple access solution was under consideration in recent years. On the other hand one of the main challenges in cellular networks was near-far effect and fading effect which cause different received powers from different users.
In this thesis we are going to investigate near-far effects in overloaded CDMA systems from different aspects. Firstly we will investigate on the robust systems over near-far effect, propose near-far resistance codes and a very low complexity ML decoder for a subclass of these codes. Secondly we deal evaluation of the sum capacity of finite dimensional CDMA systems. These systems... 

One of the major concerns in the use of light flying objects is propulsion for cruise and take off from land. Creating propulsion force is important in such way that no excessive weight is introduced, especially in case of UAVs. A common trend for propulsion in light flying objects is using propellers. Propellers are commonly driven by an external motive force and due to this force and their geometry, they convert energy from this motive force into the momentum of fluid in which they are immersed as a result a lift force is generated.In the present work, trend of propeller design with optimum performance is introduced with use of vortex theory, optimum energy loss condition or Betz condition... 

Most of the surface and ground water resources are allocated to agriculture in Iran. Even though lots of water is used in this field, the level of crop production is not satisfactory due to mismanagement. Besides, environmental issues caused by surface and ground water overuse has brought the crucial situation into the governers’ attention. Over the past two decades, Lake Urmia water basin has encountered lots of environmental issues such as decrease in lake water surface. Any effort to improve water reources consumption can be very helpful to lake restoration process. Miandoab plain known as one of the main sub basins of Lake Urmia provides the lake with more than half of its surface water... 

Presently, numerous patients die each day while they are awaiting life-saving organ transplant. Despite advances in medicine and technology, and increased awareness of organ donation and transplantation, the gap between supply and demand continues to widen. Therefore, appropriate utilization of donated organs under organ allocation process is vital, and can save several patients’ life. Due to this cause, this study presents a mixed integer multi-period mathematical model to optimize allocation system in an organ transplantation network. The considered network includes donors, hospitals, procurement centers, transplant centers, and patients. The proposed model strives to minimize the overall... 

In this research, a Ground-to-Ground axisymmetric flying vehicle is studied. In this flying vehicle the warhead is replaced by a nose having simple and cheap guidance and control. Commonly such systems include axial rotation to increase stability, which results in the malfunction of the added seekers. In this research, to overcome this problem, the rotation of the vehicle’s forward part is controlled by fuzzy control method, from the beginning of the fly. In addition, a strapdown seeker, which has high accuracy and low cost is used. This provides the system with employing Integrated Guidance and Control (IGC). The IGC, used in this research is based on fuzzy logic, which directly determines... 

In recent years, climate change due to greenhouse gases caused an increase in frequency and intensity of the natural disasters such as hurricanes, blizzards and floods. Moreover, it is anticipated that such events will increase in the future. As a result, power system decision makers are looking for methods to improve power system resiliency against such natural disasters with low occurrence probability and high impact. In this report, the distribution system resiliency has improved via placing remote control sectionalizing switches and micro grids formation during natural disasters. In this regard, the concept of resiliency and its characteristics along with the effect of remote control... 

A significant part of the power system energy losses occurs in the distribution transformers. The high loss share of these transformers in yearly electric energy losses of the country’s power network contributes to about 8% of the 20% total national electric energy losses. On the other hand due to the high rate of yearly increase in electric energy usage in the country, optimal distribution transformer planning and sizing pays an important role in reduction of these losses in the coming years. To address these concerns, the distribution companies should optimize the utilization of electric energy sources which results in an increase in their profits. This thesis introduces a new detailed... 

With the emergence and development of ultra broadband communication systems incorporating ultrashort pulses, the design of suitable receiver structures became one the most significant problems in such systems; since due the limited bandwidth and speed of current electronic devices, most of the existing receiver structures cannot be used properly. In the field of radio communications, the design of simple and low power consumption receivers for ultrawideband (UWB) and millimeter wave band communication systems, which do not rely on complex channel estimation mechanisms, is of much interest. In ultrashort light pulse optical communication systems –and specially coherent optical CDMA systems–... 

As a cost-effective and reliable alternative to supply remote areas, standalone Hybrid Energy Systems (HES) are recently under investigation to address various concerns associated with technical, financial and environmental issues. HESs are composed of renewable resources, fossil fuel generators, storage devices and power electronic converters, which are able to supply electrical and thermal loads. HESs have advantages of both renewable and fossil fuel technologies. HESs not only decrease the fuel consumption and maintenance cost of the diesel generator, but also reduce the effects of unpredictable and costly nature of renewable energy resources. Standalone hybrid energy systems should... 

In the present work, a comprehensive economic, environmental and dynamic behavior analysis with multi-objective optimization for the unit 400 of BandarEmam aromatic plant are provided and the interaction between decision variables in these criterions is discussed. In the first part, potential of seven environmental features of the operational plant are qualified and normalized using life cycle assessement (LCA) for both process waste and utility environmental impacts. By choosing the number of trays and feed stage in three distillation columns as decision variables, optimization is performed to determine the best structural variables values based on the total annual cost and Environmental... 

Additive manufacturing (AM), also known as Rapid prototyping or D printing, is a new technology for the manufacturing of the physical parts through an additive manner. In the AM process, the orientation pattern of the part is one of the most important factors that significantly affects the product properties such as the build time, the surface roughness, the mechanical strength, the wrinkling, and the amount of support material. The build time and the surface roughness are the more imperative criteria than others that can be considered to find the optimum orientation of parts. In this research, Two method is used to optimize part build orientation (PBO). In the first method a new combined...