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Improving the Control Strategy of Hybrid Electric Vehicle Equipped with
Continuously Variable Transmission
,
Ph.D. Dissertation
Sharif University of Technology
;
Saadat Foumani, Mahmoud
(Supervisor)
;
Nasser, Lashgarian Azad
(Co-Advisor)
Abstract
Hybridization of the vehicles is one of the main solutions for reducing the vehicles’ fuel consumption (FC) and emissions. Hybrid electric vehicles (HEVs) are one of the main groups of hybrid vehicles. In this type, an electric motor is employed to help the engine propel the vehicle. Other method which can be implemented to reduce the vehicle’s FC and emissions is to employ continuously variable transmission (CVT) as the vehicle power transmission. By using CVT, the engine will be able to operate in the rotational speed approximately independent of the vehicle speed, which leads to a reduction in the engine’ FC and emissions. One of the main concerns in the HEVs’ design is the layout of its...
Optimisation and comparison of different powertrain layouts for parallel hybrid electric vehicles equipped with continuous transmission
, Article International Journal of Heavy Vehicle Systems ; Volume 24, Issue 1 , 2017 , Pages 45-64 ; 1744232X (ISSN) ; Foumani, M. S ; Lashgarian Azad, N ; Sharif University of Technology
Inderscience Enterprises Ltd
2017
Abstract
The development of an efficient hybrid electric vehicle (HEV) platform needs an optimal design of its powertrain layout. This study is concerned with parallel HEVs (PHEVs) equipped with continuous transmission. First, different types of continuous transmissions, including continuously variable transmission (CVT), power-split CVT (PS-CVT) and multi-fixed ratio PS-CVT (MF-CVT), are discussed and their simulation models are presented. Also, various combinations of these continuous transmissions with PHEV configurations (namely, pre-transmission and posttransmission configurations) are introduced. Then, for a given PHEV model, several powertrain layouts resulting from combining the considered...
A new framework for advancement of power management strategies in hybrid electric vehicles
, Article International Journal of Engineering Transactions C: Aspects ; Volume 33, Issue 3 , 2020 , Pages 468-476 ; Saadat Foumani, M ; Lashgarian Azad, N ; Sharif University of Technology
Materials and Energy Research Center
2020
Abstract
Power management strategies play a key role in the design process of hybrid electric vehicles. Electric Assist Control Strategy (EACS) is one of the popular power management strategies for hybrid electric vehicles (HEVs). The present investigation proposes a new framework to advance the EACS. Dynamic Programming method is applied to an HEV model in several drive cycles, and as a result, some optimal operating regions are found. The obtained regions are almost distinct, and consequently, some threshold lines can be defined to separate them. The obtained threshold lines are used to eliminate some parameters of the EACS to reduce its sensitivity to the driving behavior. It is shown that by...
A new control strategy for hybrid electric vehicles equipped with a continuously variable transmission
, Article Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering ; Volume 230, Issue 6 , Aug , 2015 , Pages 803-816 ; 09544070 (ISSN) ; Saadat Foumani, M ; Lashgarian Azad, N ; Rostami, P ; Sharif University of Technology
SAGE Publications Ltd
2015
Abstract
The electric assist control strategy is one of the well-known methods for managing the power sources of hybrid electric vehicles. Because of the dependence of the electric assist control strategy approach on its parameters, optimization of this strategy can improve its performance, which results in lower fuel consumption and lower emission levels. However, one of the main concerns about optimization of this strategy is its dependence on the driving behaviour. This paper aims to propose a new control strategy based on the electric assist control strategy with a smaller number of control parameters and less dependence on the driving behaviour. This strategy is usable only for vehicles equipped...
Hybrid control and motion planning of dynamical legged locomotion
, Book ; Sadati, Nasser
Wiley
2012
Abstract
This book provides a comprehensive presentation of issues and challenges faced by researchers and practicing engineers in motion planning and hybrid control of dynamical legged locomotion. The major features range from offline and online motion planning algorithms to generate desired feasible periodic walking and running motions and tow-level control schemes, including within-stride feedback laws, continuous time update laws and event-based update laws, to asymptotically stabilize the generated desired periodic orbits. This book describes the current state of the art and future directions across all domains of dynamical legged locomotion so that readers can extend proposed motion planning...
Simulation of Coolant Temperature Variation in VVER-1000 Reactor Using Temperature Noise Analysis
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Nasser (Supervisor)
Abstract
Temperature noise phenomenon in nuclear reactors results to the vital information about the system. This phenomenon may originate from coolant inlet temperature fluctuations, coolant fluid velocity fluctuations or the reactor power fluctuations in PWR reactors. Diagnosis of such temperature noise sources shall improve the reactor control and protection.The present research aims to develop a software to model the temperature noise in the axial direction of a single channel comprises of fuel rod and the associated coolant to recognize the type of temperature noise sources. In this regard, research stages are as follows: first the temperature noise caused by three conventional noise sources in...
Adaptive-Robust Control of Dynamic Systems Using Orthonormal Filters
, M.Sc. Thesis Sharif University of Technology ; sadati, Nasser (Supervisor)
Abstract
In this research, using orthonormal filters, an adaptive-robust controller is designed for a class of SISO dynamic systems for which the input and output datas are available. First, Laguerre filters are combined with orthonormal Chebyshev functions to increase the capability of Laguerre filters in identification of systems with unknown dynamics. Then, the resulted Lagueree-Chebyshev structure is used for closed loop identification of the system and controller is designed. Moreover, RBF neural networks are used to approximate some nonlinear terms appearing in the controller design process.
Finally, in order to minimize the control effort, a new approach is proposed that leads to a set...
Finally, in order to minimize the control effort, a new approach is proposed that leads to a set...
, M.Sc. Thesis Sharif University of Technology ; Vosoughi, Nasser (Supervisor)
Abstract
High purity Germanium (HPGe) detector is a sub branch of semiconductor detectors which has very good resolution, very little dead time, able tobuild in large dimensions and suitable for any condition that it is using in vast fields from space investigation to radiation therapy. this detector is usually used to detecting gamma radiations furthermore the best resolution can be attained with decreasing leakage current. for analyzing about operation of the HPGe detector, it needs to initiate a model of this detector. in this studing has been used modelGEM-15190,POP-TOP which is built by ortec company. for initiating, it was used liquid nitrogen and accessory equipments like high voltage supply,...
Olympic Games Scheduling
, M.Sc. Thesis Sharif University of Technology ; Salmasi, Nasser (Supervisor)
Abstract
In the present work, the problem of Olympic Games scheduling is investigated. Due to the high number of matches and limited number of resources, scheduling of the Olympic Games is a difficult and time consuming job. Also a balanced distribution of medals on the days of Olympic Games keep each day attractive for the people and prevent sudden changes in the medal ranking of countries. So, in regard to the limitations of the problem and to balance the distribution of medals, the Olympic Games are scheduled. In order to do that, at first, two mathematical models are presented. One of them is for obtaining the feasible and optimum solution in a specified period of time. The other model presents a...
Neutronic Simulation of Pebble Bed Reactors
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Nasser (Supervisor)
Abstract
The Very-High Temperature Reactor (VHTR) design is one of the six candidates for the Generation IV nuclear reactors. The reactor core type of the VHTR design is either prismatic or pebble-bed. In pebble bed reactors, the core is filled of thousands of graphite and fuel pebbles. Fuel pebbles in these reactors consist of TRISO particles, which are embedded in a graphite matrix stochastically. The reactor core is also stochastically filled up of fuel and dummy pebbles with an unequal ratio. These two stochastic geometries are the so-called double heterogeneous of this type of reactors. In the current study, a...
A Two Criteria Objective Function Flexible Flowshop Scheduling Problem With Machine Eligibility Constraint
, M.Sc. Thesis Sharif University of Technology ; Salmasi, Nasser (Supervisor)
Abstract
This study strives to minimize a two-criterion objective function of a flexible flow shop scheduling problem with receipt and delivery of jobs in groups and processing them individually. Every group of jobs has a release time, which means that all jobs are not available at the beginning of the planning horizon. Moreover, due to the special characteristics of every job in a group, only a subset of machines at each stage are eligible to process that job. This problem has many applications in production and service industries, such as restaurants and ceramic tile manufacturing companies. The objective function is determined based on the practical applications of the problem. It deals with...
Upper and Lower Bounding Methods for Flowshop and Flexible Flowshop Group Scheduling Problems
, Ph.D. Dissertation Sharif University of Technology ; Salmasi, Nasser (Supervisor)
Abstract
In this research sequence-dependent flowshop and flexible flowshop group scheduling problems are investigated. Several upper and lower bounding methods are proposed for the research problems. Permutation flowshop sequence-dependent group scheduling problem with minimization of total completion time is considered. Since the problem is shown to be strongly NP-hard, a Memetic algorithm (MA) is proposed. A lower bounding method base on the Branch-and-Price algrithm is also proposed. A statistical comparison shows that both the proposed MA and the proposed lower bounding method have better performance than the other methods from the literature with an average 5.96% percentage gap. Flexible...
Minimizing the Number of Tardy Jobs in Flow Shop Sequence Dependent Setup Times Scheduling Problem
, M.Sc. Thesis Sharif University of Technology ; Salmasi, Nasser (Supervisor)
Abstract
This research investigates permutation flow shop scheduling problems with sequence-dependent setup times with minimizing the number of tardy jobs as criterion (Fm|prmu, Sijk|ΣUj). A mixed integer linear programming model has been developed for the research problem. As the problem is shown to be NP-hard, several meta-heuristic algorithms based on tabu search (TS) and imperialist competitive algorithm are developed to heuristically solve the problem. In order to find the best meta-heuristic algorithm, random test problems, ranging in size from small, medium, to large are created and solved by the meta-heuristic algorithms. Then, a detailed statistical experiment, based on split-plot design is...
Application of Data Mining in Healtcare
, M.Sc. Thesis Sharif University of Technology ; Salmasi, Nasser (Supervisor)
Abstract
Data mining is the one of top ten developing knowledge in the world. This study followed three fold objectives; Firstly, An efficient model based on data mining algorithms is proposed to predict the duration of hospitalization time for patients of digestive system disease that need short term care. Duration of hospitalization is an important criterion to be used for predicting the hospital resources. In order to, a combined model based on CHAID and C.5 decision trees and a neural network is suggested. The suggested model predict the duration of hospitalization with 82% accuracy. The second object of this study is to propose an algorithm based on likelihood ratio. The suggested algorithm...
Identification and Self Tuning Control of Dynamic Systems using Fractional Orthonormal Laguerre Filters
, M.Sc. Thesis Sharif University of Technology ; Sadati, Nasser (Supervisor)
Abstract
Fractional Order Transfer Functions (FOTF) in comparison to Integer Order Transfer Functions, have higher degree of freedom and as a result they can behave more dynamically. Many methods for approximation of these transfer functions have been developed in recent years allowing to implement and simulate their time-domain and frequency-domain characteristics.
Fractional order orthonormal Laguerre filters are a generalization of conventional orthonormal Laguerre filters in fractional order transfer functions domain. Orthonormal Laguerre filters have applications in signal processing and system identification. In this thesis, we investigate the application of fractional order laguerre...
Fractional order orthonormal Laguerre filters are a generalization of conventional orthonormal Laguerre filters in fractional order transfer functions domain. Orthonormal Laguerre filters have applications in signal processing and system identification. In this thesis, we investigate the application of fractional order laguerre...
Reconstruction of Noise Sources in VVER-1000 Reactors by Using Wavelet Analysis
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Nasser (Supervisor)
Abstract
Noise phenomena, which is considered as a nuisance factor, always acts as a barrier to achieve optimal performance in all systems. In Nuclear power reactors, noise can occur due to mechanical problems such as fluctuation in control rods, failure in placing Fuel assembly in their locations properly or other factors such as creation of small bubbles in moderator. Regardless of its cause, noise leaves its impact on cross section area of material within the reactor core. Change in material cross section area shows its effect in neutron flux. Although noise is a small disturbance and may not have much impact on the reactor momentarily performance itself, in case of continuity, it can leave...
Parallel Machines with Batch Processing
, M.Sc. Thesis Sharif University of Technology ; Salmasi, Nasser (Supervisor)
Abstract
Due to the undeniable importance and applicability of both "batch processing" and "parallel machines" in service and industry, this survey strives to solve a real-world problem in which some identical parallel machine, capable of processing jobs in batches, are available. In batch processing the process of jobs starts and ends simultaneously. In real world the processing time of the batch is a function of some characteristics of the jobs in the batch. in this survey, for simplicity (as calculating the mentioned function is so difficult), we assume that the processing time of a batch equals the sum of the processing time of the jobs in the batch. we also have assumed that the capacity of a...
Factors Affecting the Brand of Family Companies in Iran
, M.Sc. Thesis Sharif University of Technology ; Karami, Nasser (Supervisor)
Abstract
Although management literature about branding and family companies is very productive and rich separately, but branding is a subject in family enterprises that have been discussed in less literature. Depending on the different nature they have, family firms face different needs and challenges and else. On the other hand, demand different responses for similar needs with other companies. It seems that branding in family companies is one of the common needs in family firms which have a different response from non - family firms. In order to answer the question, what are the specific factors of family firms that affect the brand of family companies, the present research has been done. According...
Supervisory Model-based Predictive Control for Voltage Regulation of a Grid-Connected Wind Farm
, M.Sc. Thesis Sharif University of Technology ; Sadati, Nasser (Supervisor)
Abstract
Concerns about fossil fuels and the consequent effects of burning such fuels on the environment have drawn attention of different countries around the world to the development of renewable energy systems, and it has encouraged researchers to focus on expanding the methods of using different sources of renewable energy. One of the most important renewable energies is wind energy, which is generated by wind turbines. A cluster of wind turbines forms a wind farm. Wind turbines can be equipped with a supervisory control system that sends the data measured by the sensors to the operator. Design of supervisory control algorithm for a wind farm requires a model of the wind farm system. The task of...
Investigating on Characteristics of Luxury; Clustering of Iranian Society According to Perceived Characteristics of Luxury Goods Through Theoretical Dimensions and Empirical Study
, M.Sc. Thesis Sharif University of Technology ; Karami, Nasser (Supervisor)
Abstract
Due to the fast speed of changes in sciences and living conditions, concepts undergo a transformation as time goes by. Accordingly, the academic updating of such concepts in a way that is in line with the immediate perceptions of society seems necessary. The concept of luxury goods has changed a lot since old times. To understand how society perceives luxury goods, the current study aimed to make a thorough review of the past studies and investigate the characteristics of luxury goods. Then, the extracted characterizes were investigated on 355 participants by distributing questionnaires randomly. While selecting the characteristics, more emphasis was put on their innateness and the...