A dynamic programing-based framework for distribution system restoration considering load uncertainties

, Article International Transactions on Electrical Energy Systems ; Volume 27, Issue 12 , 2017 ; 20507038 (ISSN) Riahinia, S ; Abbaspour, A ; Farzin, H ; Khalili, S ; Sharif University of Technology

2017

Abstract

This paper presents a stochastic framework to properly involve the uncertainties associated with demand in distribution system restoration (DSR) problem. To reach this goal, these uncertainties are represented as probabilistic scenarios corresponding to different load levels. Subsequently, the associated stochastic optimization problem is formulated such that it can be readily solved using dynamic programming approach. Moreover, a clustering technique is presented that enables the dynamic programming approach to find near-optimal solutions for the stochastic load restoration problem with reasonable computational effort. The proposed framework is implemented on a real-world test system, and...

A neural network-based model for wind farm output in probabilistic studies of power systems

, Article 21st Iranian Conference on Electrical Engineering, ICEE 2013 ; 2013 , 14-16 May ; 9781467356343 (ISBN) Riahinia, S ; Abbaspour, A ; Fotuhi Firuzabad, M ; Moeini Aghtaie, M ; Sharif University of Technology

2013

Abstract

The penetration of wind energy in power systems has been growing due to its interminable and mild environmental effects. The intrinsic attributes of this environmentally-friendly energy, i.e., the stochastic nature of wind farms generation, however, imposes various technical and financial challenges into power systems. So, developing an accurate wind farm modeling approach aimed at taking into account the wind generation intermittency can relieve many of these challenges. Therefore, this paper takes a step to an efficient wind farm modeling procedure employing an accurate as well as well-known Neural Network (NN)-based tool. The proposed approach is comprised of two main steps. The wind...

Developing a stochastic framework to determine the static reserve requirements of high-wind penetrated power systems

, Article Journal of Intelligent and Fuzzy Systems ; Volume 29, Issue 5 , 2015 , Pages 2039-2046 ; 10641246 (ISSN) Riahinia, S ; Abbaspour, A ; Fotuhi Firuzabad, M ; Moeini Aghtaie, M ; Sharif University of Technology

IOS Press 2015

Abstract

Operational and planning studies of high-wind penetrated power systems have well come to the light as a major concern of future energy systems. This paper focuses on the procedure of determining required static reserve of the high-wind penetrated power systems which has not been well accompanied by comprehensive analysis and proper modeling tools. To reach this goal, first, a probabilistic algorithm has been proposed to effectively model the variations in output generation of wind turbines. In this algorithm, the fuzzy c-means clustering method (FCM) is exploited as an efficient as well as robust clustering method to find the multi-state model of wind turbines output generation. Based on...

Impact of correlation on reserve requirements of high wind-penetrated power systems

, Article International Journal of Electrical Power and Energy Systems ; Volume 73 , 2015 , Pages 576-583 ; 01420615 (ISSN) Riahinia, S ; Abbaspour, A ; Fotuhi Firuzabad, M ; Moeini Aghtaie, M ; Sharif University of Technology

Elsevier Ltd 2015

Abstract

This paper investigates the effects of two important factors, i.e., correlation of wind farms output with load and wind speed coincidence in determining the required static reserve in a high wind-penetrated power system. To this end, it suggests an analytical approach to involve the effects of these two factors in probabilistic analytical multi-state models of wind farms output generation. Based on an optimization framework with the objective of reaching the desirable level of correlation, the key idea is to calculate some joint probabilities for equivalent models of wind farms. As a result, these models become compatible with the ones for conventional generation units in adequacy studies of...

The Universality Classes of the KPZ Equation

, M.Sc. Thesis Sharif University of Technology Balouchi, Ashkan (Author) ; Rouhani, Shahin (Supervisor)

Abstract

Kardar-Parisi-Zhang (KPZ) equation was first proposed as a model to explain surface growth. This equation is very similar to Edwards-Wilkinson (EW) equation that is used to study scaling phenomena in non-equilibrium systems and phase transition. Although EW’s universality classes have been known well, it still remains a problem for KPZ. In the present thesis, in addition to a general review on surface growth models and a study on properties of rough surfaces, we study the physics of the KPZ model and the other related physical models. Also, using numerical results (like SLE method), renormalization group results and simulation, we study the dynamic and roughness exponents (α, z), and the...

Power Reduction Through Efficient Serial Transmission in NoCs

, M.Sc. Thesis Sharif University of Technology Bonakdar, Hojjat (Author) ; Hessabi, Shahin (Supervisor)

Abstract

With progress in integrated circuits technology, on chip systems have become operational, and after that, onchip network are as solutions to improve onchip connections and also its scalability. With improving technology, the number of cores on chips can be more, that it causes increasing importance of produced problems by parallel links. Serial links are one of the methods to decrease these problems. Serial links have some advantages in compare with parallel links in some aspects like: clock pulse skew, cross talk, area cost, difficulties in wiring and synchronizing clock pulse signals. But any way, problems such as high operational frequency and complicated serializer and deserializer...

Reducing Power Consumption in NoCs Through Adaptive Data Encoding

, M.Sc. Thesis Sharif University of Technology Taassori, Meysam (Author) ; Hessabi, Shahin (Supervisor)

Abstract

Recent advances in VLSI technology have led to integrate a few billion transistors on a chip. Systems on Chip provide solutions to the design problems of these systems. As technology scales down to deep sub-micron dimensions, the delay and power consumption of global interconnects become the major bottleneck in SoC design. Networks on Chip (NoCs) have been proposed as an efficient, scalable, modular and reliable solution to provide on chip communication in large VLSI design. The market trend to mobile digital systems and battery-powered devices add power as a new dimension to VLSI design space in addition to speed and area. Interconnect wires dissipate a significant fraction of power...

Hierarchical Optical Network-on-Chip Based on Hypercube Topology

, M.Sc. Thesis Sharif University of Technology Abdollahi, Meisam (Author) ; Hesabi, Shahin (Supervisor)

Abstract

According to prediction of ITRS, power consumption and bandwidth of processors' interconnection, will be the most major bottleneck of the System-on- Chips (SoCs) in the future. Therefore, in MultiProcessor System-on-Chip (MPSoC) architectures, the design constraints will be altered from "Computational Constraints" to "Communicational Constraints". There are three kinds of communications in the surface of the chip: Global, median and local. The main difference between global and local connections is that the length of latter one will be changed with technology. In other words, it is scalable like processor's elements while the length of global connections is practically constant. Even though...

Modified WK-Recursive Topology for an Optical Network-on-Chip

, M.Sc. Thesis Sharif University of Technology Mahdavian, Hojjat (Author) ; Hesabi, Shahin (Supervisor)

Abstract

Nowadays, a large proportion of the power consumption in high-performance multi-processor architectures on chip belongs to connections. Reducing power consumption while maintaining high efficiency in these architectures is one of the main concerns. Networks on Chip (NoC) originally were introduced to improve efficiency, but now, given the importance of power, we must provide some solutions to reduce power consumption, and delay in NOCs. Connections in chip can be divided into three categories: global, intermediate and local, while the length of global connections is almost constant in different scales, local connections are scalable. As a result improving efficiency of a small number of...

AdS3/CFT2 In The Presence of N=1 Supergravity

, M.Sc. Thesis Sharif University of Technology Fattahi, Mohammad (Author) ; Rouhani, Shahin (Supervisor)

Abstract

Brown and Henneaux showed that asymptotic symmetries of asymptotically form a conformal group in two dimensions [1]. Also they could derive classical central charge of theory. Fourteen years later, Maldacena, conjectured that this Holographic correspondence could be true for a specific theory a simplified chromodynamics in the boundary of ), this holographic theory attracted physicist communitee's attention. Many physicists tried to make this conjecture more precise. It is worth to say that, no example of holographic correspondence has been completely proven, till now, Because of the difficulty of the calculation. However these days we consider Madacena conjectrure in any arbitrary...

Analysis of Off-Critical Percolation Clusters by Schramm-Loewner Evolution

, M.Sc. Thesis Sharif University of Technology Jamali, Tayyeb (Author) ; Rouhani, Shahin (Supervisor)

Abstract

Recently, a new tool in the study of two-dimensional continuous phase transition was provided by Schramm-Loewner evolution. The main part of SLE is a conformal map which relates growth process of a two-dimensional simple curve to one-dimensional motion on the real axis (so-called Loewner driving function). Time evolution of this map and Loewner driving function is connected via the Loewner differential equation. It turns out that for a certain class of stochastic and conformally invariant curves in two dimensions, the driving function shows Brownian motion in one dimension. Strength point of SLE comes from this fact that all the geometrical properties of such curves is described through a...

Architecture of Reconfigurable Optical Network-on-Chip

, M.Sc. Thesis Sharif University of Technology Falahati, Hajar (Author) ; Hesabi, Shahin (Supervisor)

Abstract

According to power limitation on a chip and the need to simultaneously access high utilization and low power consumption, Multi-Processor System-on-Chip (MPSoC) architectures have been introduced. The major part of power consumption in a network on chip belongs to interconnects. One of the most important issues is to decrease power consumption while maintaining high utilization. The ability of optical interconnects in decreasing power consumption and increasing utilization has introduced a new architecture called optical network on chip. This architecture uses the benefits of optical signals and elements in order to transfer data. In this thesis, we introduce a new architecture with...

Energy Efficient Concurrent Test of Switches and Links for Networks-On-Chip

, M.Sc. Thesis Sharif University of Technology Alamian, Sanaz (Author) ; Hessabi, Shahin (Supervisor)

Abstract

Nowadays by increasing the number of processing cores in system-on-chip, using networks-on-chip, as an optimized interconnection foundation for transferring data between processing cores is inevitable .Based on this, the necessity of designing and implementing an optimized structure for testing network-on-chip, considering various overheads such as power consumption, latency, bandwidth and area, becomes an important issue in designing network-on-chip. The purpose of this project is to design an optimized structure for testing routers and connecting links in network, which considers power consumption overhead, latency and area overhead on one hand, and fault coverage on the other hand....

The Watershed Model and Schramm-loewner Evolution

, Ph.D. Dissertation Sharif University of Technology Daryaei, Ebrahim (Author) ; Rouhani, Shahin (Supervisor)

Abstract

Schramm Loewner evolution (SLE) is a one-parameter family of random simple curves in the complex plane introduced by Schramm in 1999 which is believed to describe the scaling limit of a variety of domain interfaces at criticality. This thesis is concerned with statistical properties of watersheds dividing drainage basins. The fractal dimension of this model is 1.22 which is consistent with the known fractal dimension for several important models such as Invasion percolation and minimum spanning trees (MST). We present numerical evidences that in the scaling limit this model are SLE curves with =1.73, being the only known physical example of an
SLE with <2. This lies outside the...

High Speed CDMA Communication in Optical Network on Chip

, M.Sc. Thesis Sharif University of Technology Abdi, Mania (Author) ; Hesabi, Shahin (Supervisor)

Abstract

As the number of processing cores on a single chip continues to grow, the need for a high band width, low power communication structure, will be the most important requirements of next generation chip multiprocessors. Today, a major part of power consumption in multi core architectures belongs to interconnects. Due to these facts, reducing consuming power, as well as supporting high performance, is concerned in these architectures. The concept of “network-on-chip” emerged to improve the performance of CMPs. But now a day, considering the circumstances of power budges, it’s incapable of presenting new strategies to decrease consuming power and delay. However, optical interconnects have the...

Design and Implementation of a 2x2 LTE Channel Simulator

, M.Sc. Thesis Sharif University of Technology Shahin, Keyvan (Author) ; Shabany, Mahdi (Supervisor)

Abstract

In this thesis, a hardware is designed and implemented for testing the perfoemance of MIMO communication systems in LTE standard using SCM channel model. This hardware can be used for measuring the BER of 2x2 wireless systems. This hardware is the first channel emulator, with hardware implementation which is using SCM channel model and implementation of a similar one has not been reported.In addition to the implementation of the mentioned channel emulator, a new approach is used for implementing a Gaussian variate generator (GVG) which is implemented on both FPGA and ASIC and shows better characteristics in comparison with the works done in the past. ASIC implementation of this part is done...

Hardware Trojan Detection: A Size-Aware Approach

, M.Sc. Thesis Sharif University of Technology Heydarshahi, Behnam (Author) ; Hesabi, Shahin (Supervisor)

Abstract

With constant increase in the rate of VLSI circuits manufactured in sites separate from the designers and computer architects, global concern regarding the possibility of integration of malware by the manufacturing foundries has arisen. Particularly, one main issue that affects reliability of the chips is modifications or additions with malicious intention,known as Hardware Trojans, which are easily applicable during design and manufacturing phase of chips. There has been an increasing fraud in chip-set manufacturing. Hardware Trojans may leak confidential information outside the chip, to the attacker, may alter the function of circuit, or completely fail a system. Hence search for new...

A Scan Chain-Based Aging Monitoring Scheme for Detection of Recycled Chips

, M.Sc. Thesis Sharif University of Technology Ostovar, Atanaz (Author) ; Hesabi, Shahin (Supervisor)

Abstract

Today's latest technology integrated circuits are manufactured for a wide range of applications. With the constant increase in the usage rate of integrated circuits, designing a high reliable system is of utmost importance. The avoidance of counterfeit components is a major challenge of hardware security and trust. Counterfeit components cause lower performance and reduced life span. They are of great concern to the manufacturers and consumers of electronic systems, impacting the security and reliability of these systems. If these parts end up in critical applications like medical systems, satellites, aerospace, or power plants, the results could be catastrophic. So far, there are different...

A Scheme for Counterfeit Chip Detection Using Scan Chain

, M.Sc. Thesis Sharif University of Technology Hashemi, Mona (Author) ; Hesabi, Shahin (Supervisor)

Abstract

With constant increase in the rate of VLSI circuits manufactured in sites separate from the designers and computer architects, global concern regarding the possibility of integration of malware by the manufacturing foundries has arisen. Particularly, one main issue that affects relability of the chips is modifications or additions with malicious intension, known as Harware Trojans, which are easily applicable during design and manufacturing phase of chip. This study intends to introduce a model based on the scan chain, a method is provided for intellectual property protection. Currently available IP protection solutions are usually limited to protect single FPGA configurations and require...

An Efficient Hardware Trojan Detector Using On-chip Ring Oscillator

, M.Sc. Thesis Sharif University of Technology Khodadadi, Mohsen (Author) ; Hesabi, Shahin (Supervisor)

Abstract

Nowadays integrated circuits are extremely vulnerable to hardware trojans (HT). Hardware trojans can be injected into the ICs in design or fabricate phase, and damage system’s functionality or security. In this thesis, we first describe hardware trojan definition, classification and types of HTs, negative effects, detection ways and analysis of them. Then we propose a new solution in order to solve the negative points of previous methods