A Comprehensive Method for Planning and Selection of Distribution Transformers Ratings and Their Asset Management

, M.Sc. Thesis Sharif University of Technology Hajiaghapour Moghimi, Mehran (Author) ; Vakilian, Mehdi (Supervisor)

Abstract

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...

A TOU-IBT pricing strategy to manage the cryptocurrency micro-miners

, Article IEEE Transactions on Smart Grid ; Volume 13, Issue 3 , 2022 , Pages 1838-1848 ; 19493053 (ISSN) Hajiaghapour Moghimi, M ; Hosseini, K. A ; Hajipour, E ; Vakilian, M ; Sharif University of Technology

Institute of Electrical and Electronics Engineers Inc 2022

Abstract

Cryptocurrency mining device (CMD) is a plug-and-play device installed by any low-voltage customer to convert electrical energy to digital money. Recently, the significant increase in the price of digital currencies has persuaded residential customers in many countries to employ CMDs to obtain quick and easy profit. However, these rapidly evolving loads can cause a substantial increase in the coincident peak load of distribution networks. Therefore, it can threaten the safe and reliable operation of the network. A straightforward way to restrict the penetration rate of these home-based miners is to increase the electricity price such that this business becomes unprofitable; however, this...

An approach to targeting cryptocurrency mining loads for energy efficiency enhancement

, Article IET Generation, Transmission and Distribution ; Volume 16, Issue 23 , 2022 , Pages 4775-4790 ; 17518687 (ISSN) Hajiaghapour Moghimi, M ; Azimi Hosseini, K ; Hajipour, E ; Vakilian, M ; Sharif University of Technology

John Wiley and Sons Inc 2022

Abstract

In recent years, the mining of cryptocurrencies such as Bitcoin has attracted much global attention due to the simplicity and high profitability of this business, especially in countries with low electricity rates. The process of cryptocurrency mining using cryptocurrency mining devices requires a significant amount of computing power. This industry, which is increasingly growing in energy and carbon emissions, can cause environmental concerns. Common ways to reduce this amount of energy consumption are to prohibit mining and charge these loads at a higher electricity rate; however, these solution methods are not feasible and applicable in many countries. This paper presents an energy...

An economic evaluation framework for cryptocurrency mining operation in microgrids

, Article International Journal of Electrical Power and Energy Systems ; Volume 142 , 2022 ; 01420615 (ISSN) Hajipour, E ; Khavari, F ; Hajiaghapour Moghimi, M ; Azimi Hosseini, K ; Vakilian, M ; Sharif University of Technology

Elsevier Ltd 2022

Abstract

The introduction of cryptocurrencies as a new form of money has attracted a tremendous amount of attention in recent years. This new financial paradigm relies on miners to validate transactions by running their cryptocurrency mining devices (CMDs). Nowadays, the significant profitability of the mining business has tempted a large number of private players in the electrical industry to employ their renewable energy resources to mine digital currency. Here, microgrid (MG) owners may use their excessive generated power to mine digital money instead of exporting it to the main grid. This paper is devoted to investigate the influential potentials of this trending business on distribution networks...

Management of Cryptocurrency Mining Penetration in Electricity Distribution Networks and Provision of the Solutions

, Ph.D. Dissertation Sharif University of Technology Hajiaghapour Moghimi, Mehran (Author) ; Vakilian, Mehdi (Supervisor) ; Hajipour, Ehsan (Supervisor)

Abstract

Currently, cryptocurrencies have attained a significant role in the financial transactions of the world, especially due to their peer-to-peer and decentralized characteristics, resulting in the elimination of intermediary oversight entities. In the cryptocurrency network, transaction security is ensured through devices known as cryptocurrency miners. People place their cryptocurrency mining devices at the disposal of the cryptocurrency network and, depending on their device’s processing power and capacity, receive rewards in the form of cryptocurrencies. Given the complexity of cryptocurrency networks, regular devices lack the ability to mine cryptocurrencies, necessitating high processing...

Hedging investments of grid-connected pv-bess in buildings using cryptocurrency mining: a case study in finland

, Article IEEE Access ; Volume 11 , 2023 , Pages 66327-66345 ; 21693536 (ISSN) Hajiaghapour Moghimi, M ; Hajipour, E ; Azimi Hosseini, K ; Tavakkoli, M ; Fattaheian Dehkordi, S ; Vakilian, M ; Lehtonen, M ; Sharif University of Technology

Institute of Electrical and Electronics Engineers Inc 2023

Abstract

In recent decades, there has been a growing global focus on solar power as a renewable energy source (RES) to supply local energy demands and reduce greenhouse gas emissions. Rooftop solar photovoltaic (PV) system provides a small-scale utilization of solar energy on the roofs of apartment buildings. Investment in this system and its profitability depends on several factors, including geographic conditions, electricity price, and local load profiles. However, in Finland, the maritime and continental climates and electrically heated residential buildings present unique challenges to the investment and utilization of rooftop PV systems. Common solutions to incentivize the investment of...

Water electrolyte transport through corrugated carbon nanopores [electronic resource]

, Article Physical Review E - Statistical, Nonlinear, and Soft Matter Physics ; Volume 90, Issue 1, July 2014, Article number 012304 Moghimi Kheirabadi . A ; Moosavi. A

Abstract

We investigate the effect of wall roughness on water electrolyte transport characteristics at different temperatures through carbon nanotubes by using nonequilibrium molecular dynamics simulations. Our results reveal that shearing stress and the nominal viscosity increase with ion concentration in corrugated carbon nanotubes (CNTs), in contrast to cases in smooth CNTs. Also, the temperature increase leads to the reduction of shearing stress and the nominal viscosity at moderate degrees of wall roughness. At high degrees of wall roughness, the temperature increase will enhance radial movements and increases resistance against fluid motion. As the fluid velocity increases, the particles do not...

Investigation of Io's auroral hiss emissions due to its motion in Jupiter's magnetosphere

, Article Research in Astronomy and Astrophysics ; Volume 12, Issue 6 , 2012 , Pages 693-702 ; 16744527 (ISSN) Moghimi, M. H ; Sharif University of Technology

2012

Abstract

The left-hand side of the auroral hiss emission observed by Galileo has a frequency time profile shaped very similar to the funnel shape observed in the Earth's auroral region. This close similarity indicates that we can use the theory of whistler-mode propagation near the resonance cone to locate the emission source. The general characteristics of the whistler mode are discussed. Then the position of the emission source is investigated using a geometrical method that takes into account the trajectory of Galileo. Initially a point source is assumed. Then the possibility of a sheet source aligned along the magnetic field lines which are tangent to the surface of Io is investigated. Both types...

Modeling Propagation of Cardiac Action Potential at Cellular Level

, M.Sc. Thesis Sharif University of Technology Farahani, Mojtaba (Author) ; Jahed, Mehran (Supervisor)

Abstract

Heartbeat is the result of contractions of over 10 billion cardiac cells. These cells’ cytoplasms are connected to each other by gap junctions which are arrays of intercellular protein channels. Thus action potential can propagate from one cell to another and cause its contraction. In core-conductor model, one-dimensional microscopic representation of cardiac tissue, cells are attached to each other to form a ladder network. The parallel elements are connected to each other by series resistors which represent gap junctions. These resistors are nearly always considered as static elements. In this thesis I have investigated the effects of incorporating the dynamicity of gap junction resistors...

Distributed Cardiovascular System Modeling

, M.Sc. Thesis Sharif University of Technology Khani, Mehrdad (Author) ; Jahed, Mehran (Supervisor)

Abstract

Simulation of cardiovascular system functionality during various physiological conditions is essential at different diagnostic and clinical levels. A first step in studying the roots of cardiovascular diseases and abnormal activity is to study a practical yet complete model of the cardiovascular system. In this thesis we introduced a new approach for defining the distributed model of the cardiovascular system. Initially, we chose an appropriate subsystem, namely Arch of Aorta, and proposed a distributed model for it. The elements of the proposed model were nonlinear RLC elements that simulate resistance, blood viscosity and vessel elasticity respectively. To minimize the system complexity,...

Risk Breakdown Structure (RBS) Identification and Designing for projects

, M.Sc. Thesis Sharif University of Technology Abdi, Mehdi (Author) ; Sepehri, Mehran (Supervisor)

Abstract

To actualize and making the outputs of a project effectual, it is necessary to conduct an effective management during a project. This case may not be possible without accurately planning for activities, management and controlling all phases of a project ignoring the risk management of that project. If risks of a project cannot be detected before conducting a project, it is possible to challenge the performance and even effectiveness of the project. In current conditions, the most important problem of managers and executives of construction projects through the country is risk management of projects, not acknowledging with definitions of risk, models of risk management and lack of a model for...

Introducing a suitable Controller for Rowing Activity in Patients with Spinal CordInjuries using FES

, M.Sc. Thesis Sharif University of Technology Zarei, Mohammad (Author) ; Jahed, Mehran (Supervisor)

Abstract

Disconnections in neural paths from the central nervous system to the muscles or vice versa cause different neuropathies, thus paralysis in different limbs may occur. As a result of the lack of muscular activity and the decrease in blood perfusion in paralyzed limbs, problems like osteoporosis, increase in the risk of breaking, decline in muscle size, cardiovascular diseases, renal dysfunction, bedsores, etc may happen. In order to induce movement in paralyzed limbs, thus preventingmentioned problems, rowing exercise through Functional Electrical Stimulation (FES) may be utilized. In FES, electrical Stimulation using current stimulating pulses is applied to contracting and relaxing muscles,...

Performance Management of HSE Management System based on BSC Framework-the Case Study of Mapna Corporation

, M.Sc. Thesis Sharif University of Technology Naseri, Amin (Author) ; Sepehri, Mehran (Supervisor)

Abstract

A Balanced Scorecard (BSC) model is proposed to evaluate performance of Health, Safety and Environment (HSE) management systems. This model includes key performance indicators at three integrated levels. It has been tested and verified in a project-based organization in Iran, active in the area of power and energy. Results show that the company has done well in implementing HSE management processes, but no so well in growth and learning. This model may be used as a basis for comparing different companies and various proposed programs in the field of HSE management systems. The model includes indicators and sub-indicators in each category particularly related to stakeholders, processes, and...

Functional Modeling of Normal and CHF Heart and Control of Total Artificial Heart- An Optimizing Approach

, Ph.D. Dissertation Sharif University of Technology Ravanshadi, Samin (Author) ; Jahed, Mehran (Supervisor)

Abstract

World-wide, Congestive Heart Failure (CHF) takes hundreds of thousands of lives each year. This chronic heart disease causes poor performance of the heart and insufficient blood pumping to the organs. A significant percentage of patients with CHF require heart transplants for their survival. The high cost of heart transplant, shortage of donor hearts and possibility of its rejection by recipients are serious problems of this type of treatment. Therefore a large number of heart patients are potential beneficiaries of artificial blood pumps such as Ventricular Assist Device (VAD) and Total Artificial Heart (TAH). Performance of these systems must be compliant and complementary to the existing...

Identifying Affecting HR Factors on Unsuccessful Reengineering Projects

, M.Sc. Thesis Sharif University of Technology Kordrostami, Melika (Author) ; Sepehri, Mehran (Supervisor)

Abstract

In this study, factors which lead in failures in reengineering processes in project based companies have been investigated. The research used qualitative methods, and finally using theme analysis to identify the main factors.Consequently, the main causes of failure of re-engineering projects have been identified and classified in six basic categories including: organizational leadership, planning, human resources management, mental models causing resistance, culture and organizational climate and communication. That each of these themes includes some subset of the agents it represents. In this study, a suitable pattern for organizations which intend to perform reengineering has been...

Applying Tandem CONWIP Policy to Assembly Supply Chain

, M.Sc. Thesis Sharif University of Technology Shokoohyar, Sina (Author) ; Sepehri, Mehran (Supervisor)

Abstract

Supply chain management has been developed extensively in second half of last century and the development has been continued up to present century. Nowadays Development and conformity of production and inventory control methods with JIT philosophy in production line level is one of the topics that received much attention from researchers. An increasing interest in the scope of JIT philosophy is on the extension and adaptation of Pull policies such as Kanban and CONWIP for materials and production control. In a real-life environment, companies are subjected to various types of uncertainties such as stochastic processing times and variable demand. This uncertain environment could cause lots...

Joint Segmentation and Motion Estimation of Cardiac Cine MR Image Sequences

, Ph.D. Dissertation Sharif University of Technology Eslami, Abouzar (Author) ; Jahed, Mehran (Supervisor)

Abstract

In this study a variational framework for joint segmentation and motion estimation is provided for inspecting heart in Cine MRI sequences. In the first work, a functional including Mumford-Shah segmentation and optical flow based dense motion estimation is proposed. However, the motion estimation technique is replaced with warping estimation in the second work to reach in more regular and smooth motion field based on tracking of cardiac boundaries. Both of these functionals are then approximated by using the phase-field method to make them suitable for extracting Euler-Lagrange equations. Numerical solution to the optimization problem, when the time and image spaces are discretized by finite...

Dynamics and Control of Needle Movement in Percutaneous Interaction with Prostate Tissue

, Ph.D. Dissertation Sharif University of Technology Maghsoudi, Arash (Author) ; Jahed, Mehran (Supervisor)

Abstract

In many modern medical procedures, needle insertion is an inevitable part of the diagnosis or treatment protocols. The accuracy of the needle insertion is adversely affected by a number of factors. A needle, frequently assumed to be flexible, is inserted into a soft tissue and induces complex mechanical interactions that may result in considerable uncertainties. Tissue intrinsic characteristics as well as its deformation and rotation may cause dramatic complexities. This work considers the needle movement inside the tissue from the dynamics and control point of view. The proposed approach can be regarded as an initial step towards automation of needle insertion procedures; it can also be...

Needle Steering in Soft Tissue

, M.Sc. Thesis Sharif University of Technology Haghighi, Payam (Author) ; Jahed, Mehran (Supervisor)

Abstract

Medical needle interventions are a common technique for accessing tissue structures.In these procedures, needles are used, for example, to extract biopsy samples, brachytherapy, and to insert drugs. In TRUS guided prostate brachytherapy application, Physicians used ulterasound imaging to steer the needle and insert radioactive seeds into cancerous tumors to irradiate surrounding tissue over several months. Prostate rotation, deformation, and unavailability of imaging data during part of the insertion path result in misplaced seeds. To overcome these problems, in this research, we modeled the prostate, its membrane and the surrounding fatty tissue as linearly elastic homogenous material, and...

Considering Lessons Learned and Ascertaining Their Roadmap in Project Management (Case Study: Sepanir Company)

, M.Sc. Thesis Sharif University of Technology Aftabi, Meysam (Author) ; Sepehri, Mehran (Supervisor)

Abstract

Evolutions in the economy, society and politics has raised knowledge as a key element in the development and competitiveness and knowledge management is considered one of the essential elements in this field. By taking temporary nature of the project into account, dynamics and competition in the project-oriented organizations business world makes the preservation and management of knowledge in project-based organizations more important. Lesson learned system is one of the knowledge management tools that can propose strategic solutions which avoid wasting of time and money and make perfect use of knowledge management accomplishments.In this study, by using literature review, interview and...