Platforms Free Fall Lifeboat design, Analysis and Modification

, M.Sc. Thesis Sharif University of Technology Esmaili, Mehdi (Author) ; Abbaspoor Tehranifard, Majid (Supervisor)

Abstract

The purpose of this study was to design a Free Fall Lifeboats body for offshore platforms, then hydrostatic and hydrodynamic analyzes, focusing on the aircavity formation on the back of the boat. In the first section, previous studies and a history of this has been discussed. Then the free fall bases are described along with the various stages of launching the Free Fall Lifeboat. In the next section, the Free Fall Lifeboat's body was designed and then analyzed and lunching procces has been simulated using the star-ccm+ software. the boat with seven different parameters is solved under the assumption that the air is incompressible, in which the primary conditions are the water entry angle...

Investigation of 3D flow in Typical Body and Decrease its Drag Coefficient at Hight Reynolds

, M.Sc. Thesis Sharif University of Technology Najdi, Ramin (Author) ; Abbaspoor, Majid (Supervisor) ; Rad, Manoochehr (Co-Advisor)

Abstract

Rapid growth in energy consumption and environmental concerns over conventional power generation technologies has increased the need for alternative energy sources. Kinetic hydropower has been available for decades, however, despite its minimal environmental impact, commercialization has been limited. The main purpose of the first part of this thesis is investigation of flow properties near the convergent-divergent nozzles with various geometries. Two parameters that studied include variation of drag force on body and mean velocity of water flow in middle cross section. In the second part, we studied a horizontal marine current turbine (which its geometry is taken from a NREL wind...

Feasibility Study and Design of Artificial Energy Island (in Persian Gulf Region)

, M.Sc. Thesis Sharif University of Technology Norouzi, Parham (Author) ; Abbaspour Tehranifard, Majid (Supervisor)

Abstract

As it is obvious from the name of this study, the goal of doing this study is the feasibility study of southern shores of Iran for building an artificial energy island for and designing it. In this project by studying seven points coastwise of southern Iran and defining the criterions and scoring the points, the Chabahar was determined as the best place for erecting the artificial energy island. With respect to the environmental condition of the chosen point and modeling in software ANSYS, the structure of the artificial energy island has been studied and the type, geometric shape, area, trough, and the setting of the anchoring system has determined. As a result of these efforts, a hexagon...

Developing the Dynamic Increasing Amplitude and Period (DIAP) Method and Investigation of its Efficiency in Ultimate Capacity Assessment of Jacket Offshore Platforms

, Ph.D. Dissertation Sharif University of Technology Imani, Hassan (Author) ; Abbaspour Tehranifard, Majid (Supervisor) ; Tabeshpour, Mohammad Reza (Co-Supervisor) ; Karimirad, Majid (Co-Supervisor)

Abstract

Dynamic increasing amplitude and period (DIAP) [1] is a time-domain analysis methodology developed based on endurance time (ET) analysis method [2], which can be used to evaluate the response of marine structures when encounters a continuous loading, such as storm conditions. In this method, instead of using separate records with different intensities, a single loading record with an increasing intensity over time is used for structural analysis. The ability to enter spectral concepts, considering the effects of waves with different frequencies and amplitudes, taking into account the effects of randomness of waves and the possibility of short duration analysis are some of the specific...

Numerical analysis of wake structure and performance of two oscillatory mechanisms of a foil: Pure pitching and undulating

, Article Proceedings of the Institution of Mechanical Engineers Part M: Journal of Engineering for the Maritime Environment ; Volume 229, Issue 4 , April , 2015 , Pages 376-396 ; 14750902 (ISSN) Abbaspoor, M ; Ebrahimi, M ; Sharif University of Technology

SAGE Publications Ltd 2015

Abstract

There are various propulsion, maneuvering, and stabilization mechanisms in nature, which can provide inspiration for similar mechanisms in man-made vehicles. This study aims to elucidate and compare the propulsive vortical signature and performance of a foil in two important natural mechanisms of pure pitching and undulatory oscillations. Governing equations are solved with a pressure-based finite volume method solver, in an arbitrary Lagrangian-Eulerian framework domain containing a NACA 0012 foil moving with prescribed kinematics. The results show that in a given Reynolds number (Re), the undulating mechanism produces thrust at a higher Strouhal number (St) and with smaller growth slope,...

An experimental study of interceptor's effectiveness on hydrodynamic performance of high-speed planing crafts

, Article Polish Maritime Research ; Volume 20, Issue 2 , 2013 , Pages 21-29 ; 12332585 (ISSN) Karimi, M. H ; Seif, M. S ; Abbaspoor, M ; Sharif University of Technology

2013

Abstract

Trim control mechanisms such as interceptors and trim flaps have been widely used in recent years in highspeed crafts for ride and trim control. In spite of their extensive application, a few studies investigating the impact of interceptors on planing craft performance, have been published. In the present study, the impact of interceptors on planing crafts hydrodynamic quality is investigated through application of an experimental method. Two scaled-down models of high-speed planing mono-hull and catamaran are tested with and without interceptors in calm water at different heights of the interceptors to investigate the effect of interceptors on drag reduction of the models. The first one is...

A study on vertical motions of high-speed planing boats with automatically controlled stern interceptors in calm water and head waves

, Article Ships and Offshore Structures ; Volume 10, Issue 3 , 2015 , Pages 335-348 ; 17445302 (ISSN) Karimi, M. H ; Seif, M. S ; Abbaspoor, M ; Sharif University of Technology

2015

Abstract

The controllable flaps and interceptors in planing crafts not only may reduce the resistance, but also could be designed to make a boat run at or near optimum attitude in various environments, which results in a reduction in both resistance and vertical motion in waves. Planing vessels suffer from porpoising instability and violent vertical motion at high forward speeds. The controllable flaps and interceptors can be used to control and reduce the vertical motion of planing crafts. In the present study, the impact of controlled interceptors on a planing craft seakeeping quality is investigated through application of experimental and theoretical methods. In the experimental part of the study,...

Identification and Detection of Cyber-Attack on Smart Grid Using Artificial Intelligence

, M.Sc. Thesis Sharif University of Technology Ganjkhani, Mohammad (Author) ; Abbaspoor Tehrani Fard, Ali (Supervisor)

Abstract

The purpose of this study is to identify the False Data Injection (FDI) attack and reconstruct the incorrect data created by FDI in the power system using machine learning algorithms. Unlike conventional power grids, the smart grids due to the increase of smart devices and communication networks to transfer power grid information from one point to another and the need to control and monitor the power grid is an electrical network that is integrated with a communication network (cyber-physical system). A communication network that transmits data between the control center and smart meters increases the threat of cyber-attacks in the power grid. In this study, the aim is to investigate the FDI...

An approach to distribution system planning by implementing distributed generation in a deregulated electricity market

, Article 2007 Large Engineering Systems Conference on Power Engineering, LESCOPE'07, Montreal, QC, 10 October 2007 through 12 October 2007 ; January , 2007 , Pages 90-95 ; 9781424415830 (ISBN) Porkar, S ; Abbaspour Tehranifard, A ; Saadate, S ; Sharif University of Technology

2007

Abstract

Electric power deregulation has drastically affected the engineering aspects of planning. In addition need flexible electric systems, changing regulatory and economic scenarios, energy savings and environmental impact are providing impetus to the development of Distributed Generation (DG), which is predicted to play an increasing role in the electric power system of the future. This opens the venue for distribution company's (Disco) aiming to minimize their investment risks by developing optimum new planning strategies to meet the load growth and satisfy the system performance at minimum cost different electricity structures. This paper proposes a framework for solving the distribution...

The Effects of Intentional Process Models on Goal Modeling and Process Conformance Checking

, M.Sc. Thesis Sharif University of Technology Farsayyad, Nazi (Author) ; Rafiei, Majid (Supervisor) ; Khedmati, Majid (Supervisor)

Abstract

In recent years, requirement engineering and goal modeling have gained more attention among different organisations. Therefore, different methods have been designed to discover stakeholders’ requirements and translate them into process and organizational goals. Various goal models have been introduced to represent these goals and their relations towards each other. Still, these methods are manual representations of different process scenarios and do not relate to the actual behavior. In 2014, Map Miner Method (MMM) was introduced to discover intentional process models from event logs. MMM uses Hidden Markov Model (HMM) as a means to represent the process as a map model of strategies and...

A Trajectory Recommendation System for Efficient Finding of Passengers

, M.Sc. Thesis Sharif University of Technology Aledavood, Ebrahim (Author) ; Khedmati, Majid (Supervisor) ; Rafiee, Majid (Supervisor)

Abstract

Recommending routes to city taxis in order to improve their performance in finding passengers can reduce traffic, pollution and waiting time for passengers, as well as this, increasing the efficiency of taxis can increase their income. In this study, by analyzing trajectory data obtained from 536 taxis in San Francisco over a period of one month, we generated networks of cells, each of which has time-dependent characteristics such as the probability of finding a passenger, the capacity of each cell, or the amount of demand exists is in the cell and the average speed of passing through that cell. also, the connections between these cells in order to make more use of the experiences of taxi...

Improving Artificial Neural Network Predictive Performance Using Panel Data

, M.Sc. Thesis Sharif University of Technology Alirezaei, Hamid Reza (Author) ; Khedmati, Majid (Supervisor) ; Rafiee, Majid (Supervisor)

Abstract

The purpose of the present study is to develop neural network estimation method for hybrid or panel data which have a combination of two cross-sectional and time series structures and because of the features of both structures, their use in different sciences offers many advantages; and the analytical methods for this data structure are also different from other one-dimensional structures, so different and specific regression models are presented for this data structure. However, in the artificial neural network method, modeling the development for this data structure is neglected, so in the present study, using the concepts of panel regression methods and their application to the...

An approach to determine spinning reserve requirements in a deregulated electricity market

, Article 2006 IEEE PES Power Systems Conference and Exposition, PSCE 2006, Atlanta, GA, 29 October 2006 through 1 November 2006 ; 2006 , Pages 1341-1344 ; 142440178X (ISBN); 9781424401789 (ISBN) Porkar, S ; Fotuhi Firuzabad, M ; Abbaspour Tehranifard, A ; Porkar, B ; Sharif University of Technology

2006

Abstract

To make the energy market reliable and transactions deliverable, transmission owners must provide required ancillary services that are critical to ensure transmission open access, and to maintain an acceptable level of power system security. Spinning reserve is one of the most important ancillary services required to maintain system reliability in case of occurring a contingency. By definition, spinning reserve is the unloaded section of synchronized generation that is able to respond immediately to serve load. Studies indicate that spinning reserve requirements have significant impacts on the energy market. A new spinning reserve market structure is proposed in this paper to best utilize...

Determination of Eddy Current Losses in Power Transformer Tank and Analysis of Methods for Reduction of These Losses

, M.Sc. Thesis Sharif University of Technology Motalleb, Mehdi (Author) ; Abbaspour Tehranifard, Ali (Supervisor) ; Vakilian, Mehdi (Supervisor)

Abstract

The leads with heavy current passing through the covering plates, and the winding in a transformer, are sources of eddy current losses. Due to this loss some regions of tank wall are subject to serious local overheating. It affects the safety and reliability of this expensive bject and power delivery.Heavy current in large power transformers and special type transformers give rise to a concentrated passage of eddy currents which in turn cause high local losses and overheating in the metallic parts especially in the steel tank walls of transformer.This local overheating is dangerous for transformer oil and the solid insulations. Therefore the calculation of losses and proper design of...

Developing a New Framework for Expansion Studies of Energy Storage Systems Considering Reconfiguration Capability of Network

, M.Sc. Thesis Sharif University of Technology Mehrabi, Mohammad (Author) ; Abbaspour Tehranifard, Ali (Supervisor) ; Moeini, Moein (Supervisor)

Abstract

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...

Predicting Wind Turbine Failures using Machine Learning

, M.Sc. Thesis Sharif University of Technology Ahmadi, Mohsen (Author) ; Abasspour Tehranifard, Ali (Supervisor) ; Fatemizadeh, Emad (Supervisor)

Abstract

Nowadays, the development of renewable energy sources is in line with the increasing capacity and installation of wind energy resources. Wind turbines, due to their installation in harsh areas, have high maintenance and repair costs, which is one of the main challenges for their further development. Given the high costs of repairs, predicting faults and planning for optimal maintenance can optimize performance and extend the useful life of the turbine. The aim of this research is to provide an approach to predict faults in wind turbines using data from the control and monitoring system. This data includes various parameters such as wind speed, output power, temperature of the generator...

Impelementation of Numerical Method For Hydrodynamic Behavior for Salvage of a Sunken Ship

, M.Sc. Thesis Sharif University of Technology Jelodari, Ehsan (Author) ; Abbaspour, Majid (Supervisor)

Abstract

One of the utmost important factors during salvage operation of drowned ships is raising velocity. Uncontrolled raise is a dynamic phenomenon which can lead to the sudden tensions, collapse in airbags or ships. Studing this issue helps the engineers which kinds of problems are more important during salvage operations. This study focus on modeling and analysis of raising movment of the ship with FLOW-3D and ABAQUS software.
In FLOW-3D environment, hydrodynamic analysis of rising movment of drowned ship has been done. We should mention that applied forces and velocities and other parameters from the FLOW-3D output should be passed IMCA Criteria to avoid uncontrollable raise. In ABAQUS...

The Application of Profile Monitoring in Healthcare for Disease Monitoring- case Study

, M.Sc. Thesis Sharif University of Technology Chabok, Sheyda (Author) ; Rafiee, Majid (Supervisor)

Abstract

Profile Monitoring is a new research topics in the field of statistical process control. In many applications of statistical quality control, sometimes quality of a process or product described by a relationship between a response variable and one or more independent variables.The researchers call this relationship profile. The study seeks to demonstrate that monitoring profiles In addition, the industry can be effective in medical field and improves control of the patient's condition by a doctor. Profiles are usually modeled with a linear regression equation, non-linear or polynomial. finally, the results of this study, using actual data, models and methods to predict and control...

Experimental Study on Extracting Clean Energy from Vortex Induced Vibration

, M.Sc. Thesis Sharif University of Technology Mohtat, Pouya (Author) ; Abbaspour, Majid (Supervisor)

Abstract

Two experimental models were designed and tested to extract energy from vortex induced vibrations of a elastically mounted one degree of freedom rigid cylinder in the Reynolds range of 120000 < Re <220000. In the first model the amplitude and frequency of the movement was measured then a second model was designed to be tested in the Emam Hossein marine laboratory. The model was designed in a way that many of its properties like mass ratio, spring constant and damping coefficient were able to be altered. In this study the vortex induced vibration of an elastically mounted cylinder was scrutinized in high Reynolds and very low mass ratios for the first time and an amplitude ratio of 2.49 were...

Optimization of Radiotherapy Plan under Uncertainty

, M.Sc. Thesis Sharif University of Technology Amir, Atabeiki (Author) ; Rafiee, Majid (Supervisor)

Abstract

As a method of cancer treatment or improvement of cancer-related complications, external radiation therapy is prescribed by physicians, in case of detection of a tumor in a region of patient’s body. Over time, various techniques have been developed for external beam radiation therapy. Among which, Intensity Modulated Radiation Therapy (IMRT), due to its ability to adjust the intensity of radiation beams, has a higher capacity to generate appropriate dose distribution based on tumor size and volume and it is one of the most widely used techniques in cancer treatment centers.The core process in treatment planning is using appropriate computer algorithms which results in posing enough damage to...