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Multi-objective optimization of job shops with automated guided vehicles: A non-dominated sorting cuckoo search algorithm
, Article Proceedings of the Institution of Mechanical Engineers, Part O: Journal of Risk and Reliability ; 2020 ; Akhavan Niaki, S. T ; Niknamfar, A. H ; Hassanlu, M. G ; Sharif University of Technology
SAGE Publications Ltd
2020
Abstract
The reliability of machinery and automated guided vehicle has been one of the most important challenges to enhance production efficiency in several manufacturing systems. Reliability improvement would result in a simultaneous reduction of both production times and transportation costs of the materials, especially in automated guided vehicles. This article aims to conduct a practical multi-objective reliability optimization model for both automated guided vehicles and the machinery involved in a job-shop manufacturing system, where different machines and the storage area through some parallel automated guided vehicles handle materials, parts, and other production needs. While similar machines...
Yield constrained automated design algorithm for power optimized pipeline ADC
, Article Integration ; Volume 74 , 2020 , Pages 55-62 ; Sadrafshari, S ; Sharifkhani, M ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Pipeline Analog to Digital Converter (ADC) design processes include several redesign steps to achieve the optimum solution. Hence, designers prefer to use automated algorithms for this purpose. In this paper, an automated algorithm for CAD tool is presented considering the trade-off between yield and power consumption for pipeline ADCs. This automated algorithm benefits from multiple degrees of freedom including the system level down to transistor level parameters, which helps CAD tools to find the optimized solution. It allows designers to choose an optimum scenario considering the trade-off between yield and power consumption. To evaluate the capabilities of this algorithm, a 10-bit...
Reliability worth assessment of an advanced centralized feeder automation scheme
, Article 2008 IEEE Electrical Power and Energy Conference - Energy Innovation, Vancouver, BC, 6 October 2008 through 7 October 2008 ; 2008 ; 9781424428953 (ISBN) ; Fotuhi Firuzabad, M ; Lehtonen, M ; Sharif University of Technology
2008
Abstract
Feeder Automation (FA) has been recognized by researchers and utilities as one of the attractive remedial measures to enhance service reliability in the electric power distribution systems. Until now, several kinds of FA schemes have been developed for automating of distribution feeders. They can be categorized into three main approaches: semiautomatic, distributed and centralized schemes. The challenge for the utilities, especially in today's competitive electricity market, is to identify and evaluate potential FA schemes and determine that appropriate for implementation. In this context, reliability cost/worth assessment plays an important role. This paper aims to propose a step by step...
Dynamic economic evaluation of distribution automation systems
, Article 2009 International Conference on Electric Power and Energy Conversion Systems, EPECS 2009 ; 2009 ; 9789948427155 (ISBN) ; Ehsan, M ; Sharif University of Technology
Abstract
In a deregulated environment of power distribution industry, a comprehensive economic evaluation for the implementation of distribution automation (DA) systems is inevitable. Using the presented methodology in this paper and system dynamics approach, it is efficiently possible to deal with variation of the economic parameters such as the interest rate, inflation rate, energy supply cost, load growth, etc. In this paper, economic short-run and long-run impacts of DA systems are evaluated from utility point of view. Also economic benefits from customers' point of view are analyzed. A practical pricing strategy for maximizing the utility profit is suggested depending on the underlying market...
Measuring the Innovation Capacity in the Firm Level, Introducing Attributes and Instrument
, M.Sc. Thesis Sharif University of Technology ; Arasti, Mohammad Reza (Supervisor)
Abstract
In this dissertation، with regard of the importance of innovation and being innovative in the competitive conditions of the markets in the world، and the need of companies for some permanent competitive advantages، we are looking for some models and finding or creating some instruments to know and create knowledge for basics of innovation and innovation capacity before measuring the outputs of innovative projects، as innovation capability، and have the needed knowledge for managing resources and having the intransitive tendency to important factors that crystallize the structure of innovation capacity. For this purpose، we had a vast literature review with reading so many books about...
Distributed Model Predictive Control and Its Application in Automated Irrigation Networks
, M.Sc. Thesis Sharif University of Technology ; Farhadi, Alireza (Supervisor)
Abstract
A distributed model predictive control with two-layer structure for communication is presented in the present thesis for elimination of the propagation and amplificationphenomenon of the upstream transient errors in automated irrigation networks. This phenomenon results in the saturation of actuators in long automated irrigation channels and therefore it results in significant reduction in the quality of service of the irrigation network. Hence, the elimination of this phenomenon in long irrigation channels is necessary, in which a distributed model predictive control with two-layer structure for communication is presented in the presentthesis for elimination of this phenomenon. Feasibility,...
Design and Development of the Automated Irrigation Channel Pilot
, M.Sc. Thesis Sharif University of Technology ; Farhadi, Alireza (Supervisor)
Abstract
The present thesis is concerned with design and development of automated irrigation system pilot. This system is obtained by equipping each regulating gate of irrigation network with a controlling hardware. This hardware is designed and developed in this project for Iran’s regulating gate, which are either slide gate or radial gate. This hardware consists of a) Ultrasonic sensor for measure gate upstream water level, b) Wireless modem for exchanging measurements between automated gates, c) controller, d) Electric motor and driver, e) shaft encoder and f) adaptor. The satisfactory performance of this hardware is shown via several experiments on the pilot
Economical Evaluation of Smart Asynchronous Measuring and Remote Reading Instrument and its application in Reducing Operation, Maintenance and Expansion of Urban Distribution Substation
, M.Sc. Thesis Sharif University of Technology ; Ehsan, Mehdi (Supervisor)
Abstract
Making distribution networks smart includes all appropriate hardware and software devices for controlling and making operation of the network optimized. (SCADA system, distribution management, communication equipments, substation automation, monitoring equipments, etc). Monitoring and management of electricity distribution networks enable us to control and record events in the operation. Equipments in the distribution substations, will be under full time monitoring and hence, we would be able to protect them against over loads, over voltages, load unbalances and inefficient usage of transformers capacity and other distribution instruments. It also enables us to manage operation switchings,...
Model Predictive Control in the Presence of Model Uncertainty and Communication Imperfections: Application in Automated Irrigation Channels
, M.Sc. Thesis Sharif University of Technology ; Farhadi, Alireza (Supervisor)
Abstract
In this thesis, at first upstream transient error propagation and amplification phenomenon is introduced. Then, the previous methods to attenuate this phenomenon are presented. To overcome this drawback, a new method that is based on feed-forward and off-take disturbance estimation and lost data reconstruction in wireless communication is presented. In this thesis, an estimation of unknown off-take disturbance at the present time is approximated or in fact predicted using the last data. Also, in the presented method, the lost data is reconstructed using two different methods. At the end, the satisfactory performance of the proposed control method is illustrated by many computer simulations
Automated Negotiation in Electronic Commerce
, M.Sc. Thesis Sharif University of Technology ; Ramezanian, Rasoul (Supervisor)
Abstract
Extensive growth of the internet has had a profound effect on the business environment and rise to a phenomenon known as electronic commerce.electronic commerce has an important role in improvement of organization performance and likewise,has influence in everyday life.despite its name,e commerce is not fully automated.typically,online transactions require a significant level of human intervention.to achieve high degree of automation,we need a new model of software.this model is based upon the notion of agents.agents can act in different stages of e-commerce.one of the most important of these stages is negotiation.negotiation capabilities are essential for e-commerce systems.the agents...
O-D Demand Estimation Based On Automatic Vehicle Identification Data
, M.Sc. Thesis Sharif University of Technology ; Shafahi, Yusef (Supervisor)
Abstract
Regardless of the traffic model and its application, an essential input of transportation models is the amount of demand which is usually described using Origin-Destination (O-D) matrix. Many reaserchers have developed different O-D matrix estimation methods using traffic counts, which allow simple data collection as opposed to the costly traditional direct estimation methods based on home and roadside interview. However, Link data is not sufficient to obtain an unique answer. This reaserch tries to estimate O-D matrix by using Automated Vehicle Identification(AVI) data. The research formulates the problem of the estimating O-D matrix as a bi-level problem. The upper level consists of...
Distribution Networks Expansion Planning Incorporating Smart Grid Technologies
, M.Sc. Thesis Sharif University of Technology ; Fotuhi-Firuzabad, Mahmud (Supervisor)
Abstract
Planning of distribution networks is usually accomplished using a cost-based conventional model that minimizes the total cost of construction and reinforcement of substations and feeders. The resulted expansion plan designed by this cost-based model is not necessarily the best choice for an electrical distribution company in the nowadays deregulated structure. This happening is mainly due to the fact that the utility seeks to maximize its profit in this competitive environment. On the other hand, this model does not consider the upcoming new challenges ahead of distribution systems, such as smart grid and automation. This thesis presents a novel profit-based model for multi-stage...
New Automatic Meet in the Middle Cryptanalysis of Block Ciphers
, Ph.D. Dissertation Sharif University of Technology ; Aref, Mohammad Reza (Supervisor)
Abstract
Block ciphers are one of the most necessary primitives for security protocols, and so, cryptanalysis of them is also essential as well. On the other hand, the security assessment of block ciphers is usually manual work with various specific-idea according to the target block cipher type and algorithm. Some basic known methods for cryptanalysis of block ciphers include linear, differential, meet in the middle, and integral attacks. However, cryptanalysis methods are not limited to them, and many new hybrid or innovative methods are employed to provide better results. Recently, automated cryptanalysis of block ciphers and proposing new methods for analyzes of these ciphers are in the...
Automatic Evaluation of Machine Translation Using Abstract Meaning Representation
, M.Sc. Thesis Sharif University of Technology ; Rezae, Saeed (Supervisor) ; Bahrani, Mohammad (Supervisor)
Abstract
Machine Translation Quality Evaluation, compared to the other issues dealt with in the field of Natural Language Processing, is faced with the challenge that the repetition of the translation process from the same linguistic form in the source language will not necessarily lead to a unique linguistic form in the target language. Therefore, considering the fact that the Abstract Meaning Representation (AMR) graph is the same for all the sentences of similar meaning, this thesis has been an attempt to extend the efficiency of AMR graphs to the area of Machine Translation Quality Evaluation. The main research question dealt with in the present thesis was whether the similarity of the AMR graphs...
Active Vibration Control of Constrained Industrial Manipulators Using Piezoelectric Actuator
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Gholamreza (Supervisor) ; Boroushaki, Mehrdad (Supervisor)
Abstract
Nowadays, due to the advancement of robotic technologies and development of industrial robots, the robot manipulators are widely used for automation of various manufacturing processes, such as finishing processes. In these applications, the contact has to be made between robot end-effector and environment. Therefore, control of interaction force in the constrained manipulators is an important demand. On the other hand, due to use of gear box and belts for energy transmission in robot joints, robot manipulators have flexible joints. The vibration, generated due to the interaction force and robot joint flexibility, can deteriorate surface roughness in automated finishing processes. In order to...
Reliability Oriented Optimal Placement of Sectionalizing Switches and Fault Indicators
, M.Sc. Thesis Sharif University of Technology ; Fotuhi-Firuzabad, Mahmud (Supervisor) ; Safdarian, Amir (Co-Advisor)
Abstract
Nowadays, electricity has a substantial impact on various aspects of peoples’ life, which has captured the attention of electricity planners and operators. However, despite the expectation of customers to have access to an uninterrupted electricity, multitude of technical and economical challenges prevent to achieve fully reliable power supply. Due to especial structure of distribution systems and limited investment budgets, distribution systems play a critical role in delivering electricity to the customers. According to past statistical information, up to 80 percent of electricity outage originates from failure of distribution equipment or the matters relevant to distribution level....
Automation of Vision Measurement Machine to Develop Parts Profile Dimensional Measurement Algorithm based on Machine Vision and Image Processing Technique Algorithms
, M.Sc. Thesis Sharif University of Technology ; Khodaygan, Saeed (Supervisor)
Abstract
Automated dimensional inspection is commonly expensive because of the requirement for high-precision measurement devices. To perform a precision measurement, the technician must be highly skilled and fully understands the operation of the equipment. Moreover, automation of the mentioned process to reduce dimensional measurement time is a complicated task due to restrictions of precise equipment such as CMM. With the expansion of the use of cameras in the industry, the measurement method with the help of machine vision systems is one of the cost-effective methods that can be achieved with the development of a suitable image processing algorithm to achieve acceptable accuracy compared to...
Design of Damask Rose Harvesting Machine and Testing a Flower Picker
, M.Sc. Thesis Sharif University of Technology ; Asghari, Mohsen (Supervisor) ; Zohoor, Hassan (Co-Supervisor)
Abstract
From the past, the damask rose has an important place in various pharmaceutical, food, health and cosmetic industries. This product has the largest cultivated area in Iran, which is about 24,000 hectares, equal to 60% of its total cultivation in the world. Considering the conditions required for the cultivation of this plant, including the low water requirement, the expansion of its cultivation has been considered. One of the important obstacles to not expanding cultivation is manual harvesting, which strongly affects the quality and mass of essential oil and rose water. The efforts that have been made so far in the field of designing and producing the rose harvesting machine have not had...
Histogram based reflection detection
, Article 2011 7th Iranian Conference on Machine Vision and Image Processing, MVIP 2011 - Proceedings, 16 November 2011 through 17 November 2011 ; November , 2011 , Page(s): 1 - 5 ; 978-1457715334 ; 9781457715358 (ISBN) ; Ahani, S ; Khalilian, H ; Gholampour, I ; Sharif University of Technology
2011
Abstract
Reflection appears as a layer that partly covers the original image. This phenomenon may cause failure in extracting information from images of reflecting objects. This work presents an automated technique for determining of reflection area as well as its severity to define reliability of extracted information. This is done by analyzing histogram and objects found in the image. We present a strong detector based on combining the results of these two procedures. We presented new reflection detection algorithm and a new method to find a good threshold value for converting any image into a binary image. The average reflection detection accuracy of the proposed algorithm is more than 95% for...
A reduced domain strategy for local mesh movement application in unstructured grids
, Article Applied Numerical Mathematics ; Volume 61, Issue 9 , 2011 , Pages 1001-1016 ; 01689274 (ISSN) ; Fouladi, N ; Sharif University of Technology
Abstract
Automatic control of mesh movement is mandatory in many fluid flow and fluid-solid interaction problems. This paper presents a new strategy, called reduced domain strategy (RDS), which enhances the efficiency of node connectivity-based mesh movement methods and moves the unstructured grid locally and effectively. The strategy dramatically reduces the grid computations by dividing the unstructured grid into two active and inactive zones. After any local boundary movement, the grid movement is performed only within the active zone. To enhance the efficiency of our strategy, we also develop an automatic mesh partitioning scheme. This scheme benefits from a new quasi-structured mesh data...