Sharif Digital Repository

In this research, soil-pile-structure in dry and wet soil conition will be investigated.Specifically the goal of the research is to study the effect of soil-pile-structure interaction on the collapse capacity of the offshore structures. To that end, initially soil-pile interaction in three soil types in dry and wet condition, has been studied. To investigate soil-pile interaction methods of FEM and Winkler springs have been implemented and in the following stages Winkler method was used for seismic soil-pile-structure interaction. Also, 2D FEM was used for soil-column analysis. Finally, an offshore jacket structure was modeled and verified using experimental data to capture collapse limit... 

Proliferation of distributed energy resources and the developing of smart grid concepts are of a great importance. This, however, influences the future of power systems and necessitates more studies in order to cope with the changes. In this regard, uncontrollability issues are arised by introducing the renewable energy resources in the power systems. To address this issue, energy storage systems are used to mitigate negative consequences of using renewable energy resources. Accordingly, in this thesis, a new framework for determining the capacity and location of the energy storage systems is proposed. In addition, reconfiguration of distribution network is also concerned in order to... 

In recent years, due to the increase in distributed generation, the use of renewable energy sources and the emergence of restructuring and energy markets, traditional distribution networks transform to complex and active distribution networks. These issues, along with requirements such as increasing power quality and reliability, have increased the need to provide active distribution management systems and the use of effective network monitoring, control and protection systems. Due to the complexity and expanse of distribution networks, as well as the development of the use of metering elements and remotely controllable elements, one of the important issues in these systems is the... 

This thesis presents a stochastic framework to properly involve the uncertainties associated with demand in distribution system restoration (DSR) problem. The restoration process returns the system back to normal operation after any combination of system components have been lost due to an outage. During restoration, the system operator executes a set of actions that progressively mitigate the outage. These actions aim at minimizing the impact of the outage on the final user without compromising the security and operability of the system. In this framework, dynamic programming (DP) is used to solve DSR problem for a distribution system that accommodates various technologies of DG units and... 

With the advances made in the last century as well as increasing consumption of non-renewable energy sources and the risk of completion of the resource, developed countries, development and use of renewable energy are taken. In the area of renewable resources, solar energy, is always available as a source, clean and inexhaustible, as one of the most important sources of renewable energy, is known. With the advancement of technology, the use of renewable energy in important industries, especially in the aerospace industry to become more common, so that examples of it in the construction of UAVs and airships is exposed to solar. In this thesis can power loop system consists of two subsystems... 

Increasing the fuel cost and concerns about pollutions have facilitated the use of renewable energies. Wind power as a renewable energy has been considered as a good representative for conventional resources of electrical energy. The biggest obstacles for efficient use of the wind energy are changeability and uncontrollability in wind farm generation and to be far from the demand center. Also, conventional approaches cannot be applied to analyze the effects of this energy on power system. With increment in the penetration of the wind energy in power system, the necessity of considering its effects, especially large scale wind farm, in transmission expansion planning (TEP) studies is... 

Large penetration of electric vehicles and distributed generation (DG) resources in upcoming years will change the future vision of distribution networks from some passive load points into active ones. The imposed load of electric vehicles charging has caused many new challenges in operation and planning studies of distribution network. In contrast, the abilities of electric vehicles in feeding back power into the network (V2G programs) has attracted attention from grid operators and also vehicles owners. So, the problem of managing charging and discharging behaviors of electric vehicles has been introduced as a hot research topic in recent year. This dissertation as the first effort in this... 

The aim of this project is decentralized control of a group of robots (swarm robots); such that the aggregation maneuver, leader following, Identification and imaging the target, will be performed so good as to make a three-dimensional model of the target from these images. Swarm robots consist of a number of similar and limited features robots which interaction in a group of robots, will lead to special features for the group. Any agent of group decides what to do only with its local information from the environment. Swarm robots are more applicable for the jobs in which a distributed perception from the environments needed, for example space exploration and military operations.In this... 

The purpose of determining orientation and position of a rigid-body is specifying its attitude and position with respect to a specified reference frame in order to using in controller. Since there is no sensor that can directly measures the attitude and position, we have to estimate those variables by observers. In this thesis we derive a new and explicit neccesary and sufficient condition for observability of the rigid-body kinematic equation. Also we propose a new observer for estimating the attitude and position of the rigid-body. The special feature of the proposed estimator is that it use only a single landmark and is globally and exponentially stable. In the next step we study the... 

In the last two decades, Supply Chain Management has become an integral part of sciences such as Management and Industrial Engineering. A key issue in this concept is how to coordinate the activities of the members of the chain in order to improve the performance of the whole system. In this thesis, the main concentration is on production, pricing and lot-sizing policies in a two-stage supply chain with a producer and a retailer. The producer manufactures the final product and vends it to the retailer, and the retailer sells it to the final customer. The customer’s demand is under iso-Elastic pattern that is one the four most popular price-sensitive demand functions. Moreover, in attempting... 

Objective: Stability is important to prevent falls during occupational and daily living activities. Control parameters such as speed, direction of motion and external load can affect stability pattern. The purpose of this study was to evaluate the effect of the mentioned control parameters on stability control pattern.
Methods: Kinematic data (rotation angles) to 19 healthy volunteers and 19 patients with low back pain associated with repeated trunk bending motion in eight different conditions of speed (high and slow), direction (symmetric and asymmetric planes) and external load (with and without load), was evaluated. Since the volunteers do during dynamic movements, they must also be... 

To study the structure of materials, among materials containing hydrogen, an instrument called the "small-angle neutron scattering instrument" is used. Having a monochromatic neutron beam is the most basic component of this instrument. This beam is often produced using a device called the "neutron velocity selector". The neutron velocity selector is a rotating mechanical piece that allows for passage of neutrons at a certain speed, according to its rotational speed. In fact, this device produces a monochromatic neutron beam with continuous flux. Until now, it has been designed and manufactured in a variety of models, which are generally divided into two groups of multi-disc and multi-blade... 

By entering the concepts of transactive energy systems, microgrids and peer-to-peer networks into the local energy market, it has made it possible to implement local energy market in the microgrids more than ever. In transactive energy systems, with the elimination of the intermediate entity, exchanges take place directly between the different parts of the system, which results in increased system flexibility and reduced system costs. In this study, by applying blockchains in local energy market and in micro-grids and transactive energy systems, a framework is proposed to implement local energy market in an energy micro-grid based on blockchain. By using blockchain features and structure,... 

In this thesis, the bidding strategy of prosumers in transactive energy markets is analyzed. Considering the repaid increase in utilizing installations that convert multiple energy together, the concept of multi-carrier energy studies has been highlighted. Moreover, with the advent of district heating networks, thermal energy markets have gained much attention lately. The agent who participates in such markets can appropriately benefit from the inherent interdependencies between various energy carriers depending on their prices in different energy markets. This market player is technically called to pose an energy hub. In this regard, to deploy the inherent abilities of such an energy... 

The issue of loss allocation is one of the most important issues that has long been considered in electricity networks, including distribution and transmission. With changes in distribution networks over the years and the penetration of distributed energy sources, the allocation of losses has become more of a challenge than ever before. Hence, there is a need for a loss allocation algorithm that can be implemented in any network and with any topology. In this dissertation, a new, simple and at the same time efficient algorithm for allocating real losses in all networks (distribution - transmission) and with any structure (radial - circular) is presented. This algorithm first tracks the...