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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Iranian Journal of Optimization
- نوع مقاله: Journal Article
- کلمات کلیدی: GA,PSO,Noisy non-linear problems
- چکیده: Optimization of noisy non-linear problems plays a key role in engineering and design problems. These optimization problems can't be solved effectively by using conventional optimization methods. However, metaheuristic algorithms such as Genetic Algorithm (GA) and Particle Swarm Optimization (PSO) seem very efficient to approach in these problems and became very popular. The efficiency of these methods against many new metaheuristic optimization algorithms has been proved in previous works, however a robust comparison between GA and PSO to solve noisy nonlinear problems has not been reported yet. Therefore, in this paper GA and PSO are adapted to find optimal solutions of some noisy mathematical models. Based on the obtained results, GA shows a promising potential in terms of number of iteration to converge and solutions found so far for either for optimization of low or elevated levels of noise.
- چکیده انگلیسی: Optimization of noisy non-linear problems plays a key role in engineering and design problems. These optimization problems can't be solved effectively by using conventional optimization methods. However, metaheuristic algorithms such as Genetic Algorithm (GA) and Particle Swarm Optimization (PSO) seem very efficient to approach in these problems and became very popular. The efficiency of these methods against many new metaheuristic optimization algorithms has been proved in previous works, however a robust comparison between GA and PSO to solve noisy nonlinear problems has not been reported yet. Therefore, in this paper GA and PSO are adapted to find optimal solutions of some noisy mathematical models. Based on the obtained results, GA shows a promising potential in terms of number of iteration to converge and solutions found so far for either for optimization of low or elevated levels of noise.
- انتشار مقاله: 26-08-1396
- نویسندگان: Hossein Towsyfyan,Amin Kolahdooz,Hazem Esmaeel,Shahed Mohammadi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Modern Processes in Manufacturing and Production
- نوع مقاله: Journal Article
- کلمات کلیدی: Experimental Test,Finite Element Analysis (FEA),Composite Lattice Cylindrical Shell,Buckling Deformation,Rib Defect
- چکیده:
- چکیده انگلیسی: In this study, the behavior of a composite lattice cylindrical shell is investigated in the buckling deforming. Also, the distribution of shell buckling response and the stress field is studied after making some defects on the ribs.Therefore using ANSYS software, a 3D finite element model of the shell has been created for the analysis. Material properties and geometrical data of the shell are obtained from the some experimental tests. In fact, these parameters have been extracted from the prototypesthat made with filament winding method. The parameters studied in this study include of the kind of ribs defects on buckling response and the geometrical ratios. Composite shells have been tested under axial force and obtained results are compared with the results of FEM. Based on the parametric study, the structural strength-to-weight ratio is increased around %50 by increasing the thickness of the outer shell. It is observed that in each consecutive buckling test, the buckling load is reduced; however the failed sample had reasonably good resistance to the applied load.
- انتشار مقاله: 26-12-1397
- نویسندگان: Amin Kolahdooz,Seyyed Ali Latifi Rostami
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Modern Processes in Manufacturing and Production
- نوع مقاله: Journal Article
- کلمات کلیدی: optimization,Imperialist competitive algorithm,Machining process
- چکیده:
- چکیده انگلیسی: Optimization of turning process is a non-linear optimization with constrains and it is difficult for the conventional optimization algorithms to solve this problem. The purpose of present study is to demonstrate the potential of Imperialist Competitive Algorithm (ICA) for optimization of multipass turning process. This algorithm is inspired by competition mechanism among imperialists and colonies, in contrast to evolutionary algorithmsthat perform the exploration and exploitation in the solution space aiming to efficiently find near optimal solutions using a finite sequence of instructions. To validate the proposed approach, the results of ICA were finally compared with Genetic Algorithm (GA).Based on the results; ICA has demonstrated excellent capabilities such as simplicity, accuracy, faster convergence and better global optimum achievement. The outcome shows the success of ICA in optimizing the machining process indicating that data analysis method developed in this work can be effectively applied to optimize machining processes.
- انتشار مقاله: 15-02-1396
- نویسندگان: Amin Kolahdooz,Hossein Towsyfyan,Seyed Adnan Adnani Salehi,Majed Ghayyem,Farid Mosaedi
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Modern Processes in Manufacturing and Production
- نوع مقاله: Journal Article
- کلمات کلیدی: optimization,Genetic Algorithm,Taguchi Method,ANN,EDM,Optimum determining
- چکیده:
- چکیده انگلیسی: Electrical Discharge Machining (EDM) process is one of the most widely used methods for machining. This method is used to form parts that conduct electricity. This method of machining has used for hard materials and therefore selects the correct values of parameters which are so effective on the quality machining of parts. Reaching to optimum condition of the DIN1.2080 alloy (D3) machining is very important due to the rapid and widespread use of different industry such as Molding, lathe tools reamer, broaching, cutting guillotine and etc. Therefore the purpose of this study is to consider the effect of the inlet parameters such as current, voltage, pulse on time and pulse off time on the machining chip rate and optimize the inlet parameters for D3 alloy. So to reach better result after doing some experiments to predict and optimize the rate of removing chip, neural network method and genetic algorithm are used. Then optimizing input parameters to maximize the rate of removing chip are performed. In this condition by decreasing time, the product cost is decreased. In this condition, the optimum parameters are obtained under the current of 20 (A), 160 (V), pulse on time of 100 (ms) and pulse off time of12 (ms). At this condition, the rate of machining chip is obtained 0.063 (cm3/min). Also, surveying the level of error and its accuracy are evaluated. According to the obtained error value that is about 5.18%, the used method is evaluated suitable for genetic algorithm.
- انتشار مقاله: 16-01-1396
- نویسندگان: Masoud Azimi,Amin Kolahdooz,Seyyed Ali Eftekhari
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Simulation and Analysis of Novel Technologies in Mechanical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: optimization,Hardness,Semi Solid Casting,A380 Aluminum Alloy,Mechanical Vibrator
- چکیده:
- چکیده انگلیسی: The use of aluminum alloys in various industries, especially the automotive industries, to have less structural weight, is on the rise. The use of semi-solid forming process in addition to changes in the microstructure which improves the mechanical properties can reduce the volume of production and ultimately lead to the improvement of the structural weight. In this paper, optimization of the governing parameters is investigated in one method of the semisolid forming named the mechanical vibration. A380 grade aluminum alloy is cast in our study. The initial parameters that investigated here are the pouring temperature, frequency and holding vibration time. The output result is investigated on the hardness. As the result showed the hardness value of 80 is the best result. Also results showed that the temperature of the melt is the important parameter in this method. Also the hardness will be increased when the frequency and holding vibration time increases
- انتشار مقاله: 14-11-1394
- نویسندگان: Saeed Ehteramian Haghighi,Amin Kolahdooz,Majid Karimian
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Simulation and Analysis of Novel Technologies in Mechanical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Electromagnetic Forming,V Shape Forming,Finite elements Simulation,Factorial Statistical method
- چکیده:
- چکیده انگلیسی: Electromagnetic power, which is one of the fast ways for forming, is used for forming workpieces without having any effect on them. Using it causes the workpieces to reach the minimum back spring and tear; consequently building the equipment like pistons will cost less than before. Electromagnetic power is used for forming Aluminium sheets into V shapes in this study. As the coils connect the machine and the workpieces, the number of rounds and the voltage in 10 levels will be discussed in this study. Considering the results and analysis that have been reached, the best forming occurs in the voltage of 1500 and 35 rounds. Because the machine creates a high ampere and a proper amount of rounds in this voltage in order to transfer the whole power to the workpiece. As the rounds increase to 40, the forming will decrease up to 34/3 percent
- انتشار مقاله: 28-08-1395
- نویسندگان: Sajad Nadian Bersiani,Ahmad Keshavarzi,Amin Kolahdooz
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Simulation and Analysis of Novel Technologies in Mechanical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: RSM,bar,hot rolling,HSS roler,Notching
- چکیده:
- چکیده انگلیسی: One of the biggest problems of artisans , is notching the high speed steel roller is due to the inability to do this work, become high speed steel roller bearings are disposable. One of the biggest problems of artisans , is notching the high speed steel roller is due to the inability to do this work, become high speed steel roller bearings are disposable.When the roller is placed on the production line, because of the retained austenite make it very hard. High speed roller used in this study is barely above 70 Shc. Our goal is to obtain the optimum machining parameters that it requires a high number of tests that are practically impossible. So in order to achieve optimal machining parameters with the lowest test, RSM method in Minitab software was used. CBN tools performed well in all tests and succeeded with the best cutting speed 25 m/min, 0.05 mm feed and 0.05 mm depth of cut at the time of 1080 seconds, in notching one caliber.
- انتشار مقاله: 03-04-1395
- نویسندگان: Mohsen Jafari Dinani,Amin Kolahdooz,Seyyed Ali Eftekhari
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Simulation and Analysis of Novel Technologies in Mechanical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Genetic Algorithm,Neural network,Taguchi,Electrical Discharge Machining,Optimum determinant Optimization
- چکیده:
- چکیده انگلیسی: Electrical discharge machining process is one of the most Applicable methods in Non-traditional machining for Machining chip in Conduct electricity Piece that reaching to the Pieces that have good quality and high rate of machining chip is very important. Due to the rapid and widespread use of alloy DIN1.2080 in different industry such as Molding, lathe tools, reamer, broaching, cutting guillotine, etc. Reaching to optimum condition of machining is very important. Therefore the main aim in this article is to consider the effect of input parameter such voltage, Current strength, on-time pulse and off-time pulse on the machining chip rate and optimizing this in the electrical discharge machining for alloy DIN1.2080. So to reach better result after doing some experiments to predict and optimize the rate of removing chip, neural network method and genetic algorithm are used. Then optimizing input parameters to maximize the rate of removing chip are performed. In this condition, by decreasing time, the product cost is decreased. Optimum parameters in this experiment in this condition are obtained under Current strength 20 ampere, 160 volt, on-time pulse 100 micro second and off-time pulse 12 micro second that is obtained 0.063 cm3/min as rate of machining chip. After doing experiment, surveying the level of error and its accuracy are evaluated. According to the obtained error value that is about 5.18%, used method is evaluated for genetic algorithm
- انتشار مقاله: 08-12-1395
- نویسندگان: Masoud Azimi,Amin Kolahdooz,Seyyed Ali Eftekhari
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Simulation and Analysis of Novel Technologies in Mechanical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Composite,FEM,Buckling analysis,Critical Lattice Structure,Rib (Stiffener)
- چکیده:
- چکیده انگلیسی: Due to their light weights and high load carrying capacities, composite structures are widely used in various industrial applications especially in aerospace industry. Stiffening ribs are the main features of lattice type composite structures. Strength to weight ratio is known to be as one of the most critical design parameter in these structures. In this study, the effect of some parameters such as the physical characteristics of the material, shell thickness, angle, thickness and number of ribs on distribution of stresses and buckling loads of shell are investigated. For this purpose, 3D finite element analysis using ANSYS software explicitly was done and then compared with experimental test results. Increasing the thickness of the outer shell causes the structural strength will rise to 50 percent. The next effective parameter is reduction of rib angle which provides an increase of 30 percent in specific load. Although Stiffenerrs (ribs) have a major role in load carrying, but increasing the rib number causes the structural weight rises, thus compared with the two previous parameters do not have a significant effect on the strength of structures
- انتشار مقاله: 09-10-1394
- نویسندگان: S.A. Latifi-rostami,R. Akbari Alashti,Amin Kolahdooz
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Simulation and Analysis of Novel Technologies in Mechanical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: optimization,Genetic Algorithm,casting,Al-A360,Natural Network
- چکیده:
- چکیده انگلیسی: Semi-Solid Casting (SSM) is a new process that could produce globular structures with mechanical properties. The cooling slope method (CLM) is a one of this process that was employed to produce the A360 feedstock. In this method, The dendritic primary phase in the conventionally cast A356 alloy has transformed into a non-dendritic one. In this paper, The molten alloy with the temperature (PT) of 670, 650, 630, 610 and 590ºC was poured on the surface of the plate where cooled with water circulation in various cooling angles (CA) and lengths (CL). After pouring, the melt which became semi-solid at the end of the plate was consequently poured into cylindrical steel mold with different mold temperatures (MT). Then, a back-propagation neural network was design to correlate the process parameters. Finally, genetic algorithm (GA) was used to optimize the process parameters. Results indicated that the hardness of samples changed with PT and MT. In the best condition with changes on PT, the hardness increased 15% and it increased 5% with changes on MT. The hardness is increased around 12% and 9% with changes on CL and CA consequently. The strength is increased around 13% and 6% with changes on CL and CA consequently.
- انتشار مقاله: 07-10-1394
- نویسندگان: Amin Kolahdooz,M. Loh-Mousavi
- مشاهده