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A Branch and Cut Algorithm for Resource-Constrained Project Scheduling Problem Subject to Nonrenewable Resources with Pre-Scheduled Procurement
, Article Arabian Journal for Science and Engineering ; Vol. 39, Issue. 11 , November , 2014 , pp. 8359-8369 ; ISSN: 13198025 ; Shadrokh, S ; Sharif University of Technology
2014
Abstract
In the project scheduling literature, nonrenewable resources are assumed to be available in full amount at the beginning of the project. However, in practice, it is very common that these resources are procured along the project horizon according to some pre-scheduled plan. In this paper, we study an extended form of the resource-constrained project scheduling problem that is subject to this type of nonrenewable resources in addition to the renewable resources. In order to solve this problem, we propose a branch and cut algorithm. We incorporate with the algorithm some technics and fathoming rules to shorten the solving process. The algorithm is capable of specifying lower bounds for the...
Branch and bound algorithms for resource constrained project scheduling problem subject to nonrenewable resources with prescheduled procurement
, Article Mathematical Problems in Engineering ; Vol. 2014, issue , 2014 ; ISSN: 1024123X ; Shadrokh, S ; Fathi, Y ; Sharif University of Technology
2014
Abstract
A lot of projects in real life are subject to some kinds of nonrenewable resources that are not exactly similar to the type defined in the project scheduling literature. The difference stems from the fact that, in those projects, contrary to the common assumption in the project scheduling literature, nonrenewable resources are not available in full amount at the beginning of the project, but they are procured along the project horizon. In this paper, we study this different type of nonrenewable resources. To that end, we extend the resource constrained project scheduling problem (RCPSP) by this resource type (RCPSP-NR) and customize four basic branch and bound algorithms of RCPSP for it,...
A hybrid genetic and Lagrangian relaxation algorithm for resource-constrained project scheduling under nonrenewable resources
, Article Applied Soft Computing Journal ; Volume 94 , 2020 ; Shadrokh, S ; Khakifirooz, M ; Fathi, M ; Pardalos, P. M ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
Scheduling under nonrenewable resources is one of the challenging issues in project scheduling problems. There are many cases where the projects are subject to some nonrenewable resources. In most of the literature, nonrenewable resources are assumed to be available in full amount at the beginning of the project. However, in practice, it is prevalent that these resources are procured along the project horizon. This paper studies the generalized resource-constrained project scheduling problem (RCPSP) where, in addition to renewable resources, nonrenewable resources are considered, such as budget or consuming materials by the project activities. As the problem is NP-hard, some sub-algorithm...
A distributed truthful routing protocol for mobile ad hoc networks
, Article Proceedings of ICCIA 2010 - 2010 International Conference on Computer and Information Application, 2 November 2010 through 4 November 2010, Tianjin ; 2010 , Pages 133-140 ; 9781424485963 (ISBN) ; Movaghar, A ; Shirzadeh, E ; Sharif University of Technology
2010
Abstract
In Mobile Ad hoc Networks (MANETs), nodes depend on each other for routing and forwarding their packets. However, to save power and other resources, nodes belonging to independent authorities may behave selfishly, and not cooperate in network activities. Such selfish behaviour poses a real threat to the proper functioning of MANETs. To cope with this situation, a motivation stimulation mechanism is required to provide sufficient incentives for nodes to forward other nodes' packets. One appropriate approach is to have network nodes pay in order to motivate them to cooperate with the protocol. To achieve truthfulness, the payment should be based on the cost of transmission of packets. Since...
A modified PSO algorithm for minimizing the total costs of resources in MRCPSP
, Article Mathematical Problems in Engineering ; Volume 2012 , 2012 ; 1024123X (ISSN) ; Kianfar, F ; Shirzadeh Chaleshtari, A ; Shadrokh, S ; Ranjbar, M ; Sharif University of Technology
2012
Abstract
We introduce a multimode resource-constrained project scheduling problem with finish-to-start precedence relations among project activities, considering renewable and nonrenewable resource costs. We assume that renewable resources are rented and are not available in all periods of time of the project. In other words, there is a mandated ready date as well as a due date for each renewable resource type so that no resource is used before its ready date. However, the resources are permitted to be used after their due dates by paying penalty costs. The objective is to minimize the total costs of both renewable and nonrenewable resource usage. This problem is called multimode resource-constrained...
Modeling of Human Decision Making in Problem Solving Based on Physiological Models of Neuron
, M.Sc. Thesis Sharif University of Technology ; Vosughi Vahdat, Bijan (Supervisor)
Abstract
How the human nervous system works is one of the most important topics in science and in this topic providing a model of it is scientists' main concern. The human brain that has been formed from a large number of nerve cells lets it do complex computations. The structure of cognition, memorizing and processing which are some of human features are being studied in many fields of science named "brain and cognitive science".
In this study, we will point to modeling of one of the human cognitive phenomena (decision making in problem solving). In this modeling, we aim to connect the microscopic and macroscopic levels of the nervous system to each other.
First, we will give an introduction...
In this study, we will point to modeling of one of the human cognitive phenomena (decision making in problem solving). In this modeling, we aim to connect the microscopic and macroscopic levels of the nervous system to each other.
First, we will give an introduction...
Project Scheduling Subject to Nonrenewable Resource with Proscheduled Procurement
, Ph.D. Dissertation Sharif University of Technology ; Shadrokh, Shahram (Supervisor)
Abstract
Among various types of resources defined in the project scheduling literature, the most studies have been conducted on the renewable and nonrenewable resource types. Definition of different resources in the project scheduling literature is based on the specification of the resources in the real projects. Yet there are some sort of nonrenewable resources in the real projects that are not exactly similar to the type defined in the project scheduling literature. The difference stems from this fact that in the project scheduling literature, it is supposed that the nonrenewable resources required for the execution of the project activities are available in full amount at the beginning of the...
Surface Modification of Super Paramagnetic Iron Oxide Nanoparticles (SPIONs)for Cell Separation
, M.Sc. Thesis Sharif University of Technology ; Maddah Hoseini, Hamid Reza (Supervisor)
Abstract
The aim of this project is the surface modification of super para magnetic iron oxide (SPIONs), leading to oriented covalent bonding of antibody(AB) to these nanoparticles (NPs) and improve the efficiency of cell separation at MACS columns. For this purpose, SPIONs synthesized by co-precipitation method, and the stability of colloidal NPs then was provided by coating with Dextran . We used TGA to measure weight percentage of dextran. Some properties like particle size, hydrodynamic diameter, presence of coating and superparamagnetic properties were characterized by XRD (16 nm), FTIR, DLS (73 nm), TEM (20nm) and VSM (≈76/78 emu/g) method, respectively. Then we tried to immobilize AB on NPs...
Application of Magnetic Grapheme Oxide Coated by Modified Carboxymethyl Cellulose as a Nanoadsorbent to Dye Removal
, M.Sc. Thesis Sharif University of Technology ; Pourjavadi, Ali (Supervisor) ; Alamolhoda, Ali Asghar (Supervisor)
Abstract
There are many industries in the world that produce colorized wastewater. Because of the complex structure and good solubility of dyes, such industries have problem treating this wastewaters. On the other hand, because of the toxicity of these materials for water living, dye removal from discharged wastewater of these industries is very important. In recent years, researchers have become interested in the synthesis of dye Nano adsorbents and they have published many works on this subject. The important parameters in the synthesis of such adsorbent include; non-toxicity, high adsorption capacity and easy separation. In this project, cellulose was extracted from bagasse and then CMC was...
Adaptive fuzzy nonlinear sliding-mode controller for a car-like robot
, Article 5th IEEE Conference on Knowledge Based Engineering and Innovation, KBEI 2019, 28 February 2019 through 1 March 2019 ; 2019 , Pages 686-691 ; 9781728108728 (ISBN) ; Shojaeefard, M. H ; Amirkhani, A ; Behroozi, H ; Intelligent Systems Scientific Society of Japan; Iran Computer and Video Games Foundation; Islamic World Science Citation Center (ISC) ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2019
Abstract
In this paper, a nonlinear controller, which can be updated online by means of fuzzy logic, has been proposed for tracking the trajectory of a car-like robot. The advantage of this control scheme is that it eliminates the effects of model disturbances and uncertainties, which cannot be avoided; and especially when we consider the difficult task of determining the exact kinematic and dynamic models of car-like robots. The proposed approach comprises a robust nonlinear section that uses the sliding mode control and a fuzzy section that can update, online, parameters of the nonlinear controller. The stability and the error convergence of the closed-loop system are verified through the Lyapunov...
Intelligent semi-active vibration control of eleven degrees of freedom suspension system using magnetorheological dampers
, Article Journal of Mechanical Science and Technology ; Volume 26, Issue 2 , 2012 , Pages 323-334 ; 1738494X (ISSN) ; Sarrafan, A ; Khayyat, A. A. A ; Zabihollah, A ; Sharif University of Technology
2012
Abstract
A novel intelligent semi-active control system for an eleven degrees of freedom passenger car's suspension system using magnetorheological (MR) damper with neuro-fuzzy (NF) control strategy to enhance desired suspension performance is proposed. In comparison with earlier studies, an improvement in problem modeling is made. The proposed method consists of two parts: a fuzzy control strategy to establish an efficient controller to improve ride comfort and road handling (RCH) and an inverse mapping model to estimate the force needed for a semi-active damper. The fuzzy logic rules are extracted based on Sugeno inference engine. The inverse mapping model is based on an artificial neural network...
Performance and exhaust emission characteristics of a spark ignition engine operated with gasoline and CNG blend
, Article Proceedings of the Spring Technical Conference of the ASME Internal Combustion Engine Division ; 2012 , Pages 179-187 ; 15296598 (ISSN) ; 9780791844663 (ISBN) ; Hamidi, A. A ; Mozafari, A. A ; Sharif University of Technology
2012
Abstract
Using CNG as an additive for gasoline is a proper choice due to higher octane number of CNG enriched gasoline with respect to that of gasoline. As a result, it is possible to use gasoline with lower octane number in the engine. This would also mean the increase of compression ratio in SI engines resulting in higher performance and lower gasoline consumption. Over the years, the use of simulation codes to model the thermodynamic cycle of an internal combustion engine have developed tools for more efficient engine designs and fuel combustion. In this study, a thermodynamic cycle simulation of a conventional four-stroke spark-ignition engine has been developed. The model is used to study the...
A comparative study of the performance of a SI engine fuelled by natural gas as alternative fuel by thermodynamic simulation
, Article 2009 ASME Internal Combustion Engine Division Fall Technical Conference, ICEF 2009, Lucerne, 27 September 2009 through 30 September 2009 ; 2009 , Pages 49-57 ; 9780791843635 (ISBN) ; Hamidi, A. A ; Mozafari, A. A ; Sharif University of Technology
American Society of Mechanical Engineers (ASME)
2009
Abstract
With the declining energy resources and increase of pollutant emissions, a great deal of efforts has been focused on the development of alternatives for fossil fuels. One of the promising alternative fuels to gasoline in the internal combustion engine is natural gas [1-5]. The application of natural gas in current internal combustion engines is realistic due to its many benefits. The higher thermal efficiency due to the higher octane value and lower exhaust emissions including CO2 as a result of the lower carbon to hydrogen ratio of the fuel are the two important feature of using CNG as an alternative fuel. It is well known that computer simulation codes are valuable economically as a cost...
Analytical and experimental analyses of nonlinear vibrations in a rotary inverted pendulum
, Article Nonlinear Dynamics ; Volume 107, Issue 3 , 2022 , Pages 1887-1902 ; 0924090X (ISSN) ; Pasharavesh, A ; Khayyat, A. A. A ; Sharif University of Technology
Springer Science and Business Media B.V
2022
Abstract
Gaining insight into possible vibratory responses of dynamical systems around their stable equilibria is an essential step, which must be taken before their design and application. The results of such a study can significantly help prevent instability in closed-loop stabilized systems by avoiding the excitation of the system in the neighborhood of its resonance. This paper investigates nonlinear oscillations of a rotary inverted pendulum (RIP) with a full-state feedback controller. Lagrange’s equations are employed to derive an accurate 2-DoF mathematical model, whose parameter values are extracted by both the measurement and 3D modeling of the real system components. Although the governing...
A suction-controlled ring device to measure the coefficient of lateral soil pressure in unsaturated soils
, Article Geotechnical Testing Journal ; Volume 44, Issue 1 , 2020 ; Garakani, A. A ; Golshani, A ; Mirzaii, A ; Sharif University of Technology
ASTM International
2020
Abstract
A suction-controlled ring device has been developed to continuously measure the coefficient of lateral soil pressure in deformable unsaturated soil samples from the at-rest to the active condition under application of increasing vertical pressure and controlled matric suction. The device incorporates a thin aluminum specimen ring equipped with horizontal strain gages for recording the lateral soil strains. In addition, a sensor recording water volume changes is utilized to continuously monitor the degree of saturation of the soil sample during tests. The matric suction within the soil texture is controlled using the axis translation technique. In order to verify the performance of the ring...
Gum tragacanth gels as a new supporting matrix for immobilization of whole-cell
, Article Iranian Journal of Chemistry and Chemical Engineering ; Volume 24, Issue 4 , 2005 , Pages 1-7 ; 10219986 (ISSN) ; Vaziri, A ; Seifkordi, A. A ; Kheirolomoom, A ; Sharif University of Technology
2005
Abstract
We introduce a new smooth, non-toxic, biocompatible method for cross-linking of gum tragacanth (GT), a polysaccharide of natural origin, in order to serve as a new supporting matrix for immobilization systems. The modified gum is used as a matrix for the catalysis of the conversion of benzyl penicillin to 6-aminopenicillanic acid (6-APA) by means of Escherichia coli ATCC11105 with penicillin G acylase (PGA) activity. The results show that GT beads can not only serve as a proper matrix for immobilization, but show enhanced hydrolysis rate and stability compared to other immobilization systems used for this reaction. This signifies the potential of GT as a biocompatible matrix for...
True Class-E Design For Inductive Coupling Wireless Power Transfer Applications
, Article 30th International Conference on Electrical Engineering, ICEE 2022, 17 May 2022 through 19 May 2022 ; 2022 , Pages 864-868 ; 9781665480871 (ISBN) ; Safarian, A ; Fotowat Ahmady, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
The Class-E power amplifier has been widely studied and formulated in the literature. Although the majority of reported inductive coupling wireless power transfer (WPT) systems use a class-E power amplifier for driving the primary coil, still there is a lack of a comprehensive study on class-E circuit dedicated to WPT, providing a set of closed form design equations for proper class-E operation. This paper presents the required design equations needed to design a 'true' class-E circuit for WPT applications. Equations for the series-tuned secondary coil WPT system are presented, as well as two different design procedures for the parallel-tuned secondary coil. The derived equations have been...
Crashworthiness determination of side doors and B pillar of a vehicle subjected to pole side impact
, Article Applied Mechanics and Materials ; Vol. 663, issue , 2014 , p. 552-556 ; Faieza, A. A ; Sahari, B. B ; Nuraini, A. A ; Halali, M ; Sharif University of Technology
2014
Abstract
Pole Side Impact Tes is one out of three crash tests described by Euro NCAP standard for star rating of a vehicle and is required for assessing the Adult Occupant Protection. In this paper the goal is to determine the crashworthiness of side doors and B pillar in a Pole Side Impact Test based on Euro New Car Assessment Program (Euro-NCAP) using computer and simulation method. In this matter, a vehicle model has been prepared and meshed using Hypermesh and CATIA. The velocity of 29 km/h has been assigned to the vehicle which was on top of a cart while the pole has been assigned as a rigid static object based on Euro NCAP requirements specifically. Results show that different amounts of energy...
Investigation of Thickness Influences On Energy Absorption For Side Doors And B Pillar In Euro NCAP Pole Side Impact Test
, Article Applied Mechanics and Materials ; Vol. 663, issue , Oct , 2014 , p. 585-589 ; Faieza, A. A ; Sahari, B. B ; Nuraini, A. A ; Halali, M ; Sharif University of Technology
2014
Abstract
To assess a car under the Euro New Car Assessment Program (Euro-NCAP), Adult Occupant Protection is one out of three parameters which need to be calculated with a weight factor of 50% while the other parameters, Child Occupant Protection and Pedestrian Occupant Protection, have a weight factor of 20%. The Pole Side Impact Test, beside two other tests, Side and Front Impact, is also required to calculate the Adult Occupant Protection. It shows how important the Pole Side Impact Test is and what an effective role it has in the car rating assessment. In this paper, the objective is to evaluate the effect of thickness on the energy absorbed by the side doors and the B pillar and its...
Crashworthiness determination for front and rear doors and B pillar subjected to side impact crash by a mobile deformable barrier
, Article Advanced Science Letters ; Volume 19, Issue 2 , 2013 , Pages 392-395 ; 19366612 (ISSN) ; Faieza, A. A ; Sahari, B. B ; Nuraini, A. A ; Halali, M ; Sharif University of Technology
2013
Abstract
In Euro NCAP standard, adult protection is one of the most important rating scores with 50% weight factor while child protection and pedestrian protection are accounted into consideration with 20% weight factor. For adult protection testing, three tests are required to perform: (1) side impact, (2) pole impact, (3) front impact. In the side impact test, dummy's head, chest, shoulder, thorax, ribs, abdomen, pelvic and femur must be studied to evaluate the rating score. Crashworthiness of a car during side impact can describe the score rated for that car. In this paper the goal is to determine the crashworthiness of side doors and B-pillar in side impact crash est by simulation using LS DYNA...