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Application of Branch-and-bound Method, Scatter Search Algorithm, and Particle Swarm Optimization Method in Solving Some Resource-Constrained Project Scheduling Problems
, Ph.D. Dissertation Sharif University of Technology ; Kianfar, Fereydoon (Supervisor) ; Rowghangar Ranjbar, Mohammad (Supervisor)
Abstract
The main goal of this thesis is to reduce the gap between the theoretical and actual project scheduling problems by introducing three problems and then proposing three different exact and meta-heuristic algorithms to solve them. These problems are as follows: the Resource-Constrained Project Scheduling Problem with Minimization of Total Weighted Resource Tardiness Penalty Costs (RCPSP-TWRTPC), the Resource-Constrained Project Scheduling Problem with Discounted Cash Flows of Weighted Earliness-Tardiness Costs (RCPSP-DCWET), and the Multi-Mode Resource-Constrained Project Scheduling Problem with Minimization of Total Weighted Resource Tardiness Penalty Costs (MRCPSP-TWRTPC). Also, we develop a...
Using flower pollinating with artificial bees (FPAB) technique to determine machinable volumes in process planning for prismatic parts
, Article International Journal of Advanced Manufacturing Technology ; Volume 45, Issue 9-10 , 2009 , Pages 944-957 ; 02683768 (ISSN) ; Imani, D. M ; Niaki, S. T. A ; Sharif University of Technology
Abstract
Process planning (PP) has an important role in manufacturing systems design and operations. Volume decomposition and machinable volumes (MVs) or machining features determination is the core activity in process planning. This process requires extraction of elementary volumes (EVs), merging or clustering EVs to construct feasible MVs and finally selecting an optimal combination of MVs. Development of MVs is an important activity, so that better solution is obtained by better developed MVs. Generation of limited number of MVs or machining features, which is often performed by experts may miss the optimal solution. Also, using exact methods such as combinatorial optimization not only generate...
Optimization of tree-structured gas distribution network using ant colony optimization: A case study
, Article International Journal of Engineering, Transactions A: Basics ; Volume 25, Issue 2 , 2012 , Pages 141-158 ; 17281431 (ISSN) ; Mahdavi, I ; Mahdavi Amiri, N ; Tafazzoli, R ; Sharif University of Technology
Materials and Energy Research Center
2012
Abstract
An Ant Colony Optimization (ACO) algorithm is proposed for optimal tree-structured natural gas distribution network. Design of pipelines, facilities, and equipment systems are necessary tasks to configure an optimal natural gas network. A mixed integer programming model is formulated to minimize the total cost in the network. The aim is to optimize pipe diameter sizes so that the location-allocation cost is minimized. Pipeline systems in natural gas network must be designed based on gas flow rate, length of pipe, gas maximum pressure drop allowance, and gas maximum velocity allowance. We use the information regarding gas flow rates and pipe diameter sizes considering the gas pressure and...
Nonlinear cylindrical bending analysis of shear deformable functionally graded plates under different loadings using analytical methods
, Article International Journal of Mechanical Sciences ; Volume 50, Issue 12 , 2008 , Pages 1650-1657 ; 00207403 (ISSN) ; Haddadpour, H ; Sharif University of Technology
2008
Abstract
An exact solution is presented for the nonlinear cylindrical bending and postbuckling of shear deformable functionally graded plates in this paper. A simple power law function and the Mori-Tanaka scheme are used to model the through-the-thickness continuous gradual variation of the material properties. The von Karman nonlinear strains are used and then the nonlinear equilibrium equations and the relevant boundary conditions are obtained using Hamilton's principle. The Navier equations are reduced to a linear ordinary differential equation for transverse deflection with nonlinear boundary conditions, which can be solved by exact methods. Finally, by solving some numeral examples for simply...