@article { author = {Talebpour, Mohammad Hosein and Naderi, Reza and Naghizadeh, Ali and kalatjari, Vahid reza}, title = {Base Level Evaluation in Buildings with Different Foundation Levels by Soil-foundation-structure Interaction}, journal = {International Journal of Engineering}, volume = {30}, number = {9}, pages = {1288-1297}, year = {2017}, publisher = {Materials and Energy Research Center}, issn = {1025-2495}, eissn = {1735-9244}, doi = {}, abstract = {The base level is among the effective parameters in determining the seismic force on a structure, if the equivalent-static method is used for analyzing a structure. It is obvious that the base level is located on foundation in buildings in which foundation is built in a single level and there is not any interaction between the structure's walls and the soil; however, in some buildings which have underground part, the foundation is built in two different levels which in turn makes the determination of the location of base level uncertain. Since no relevant recommendation has been provided in the seismic codes, this study tries to remove such uncertainties. For this purpose, the structural models along with foundation and their peripheral soil were modeled by the ABAQUS software and regarding the soil type it was tested by an artificial accelerogram compatible with the spectrum of the code. Two types of soil (stiff and soft) were used in this study. The results indicated that the base level location is considerably influenced by the soil type, the number of entrance columns leading to the underground and the number of stories of the structure.}, keywords = {Base level,Soil,Foundation,structure interaction,Different Foundation Levels,Artificial accelerogram}, url = {https://www.ije.ir/article_73008.html}, eprint = {https://www.ije.ir/article_73008_058caa5c010cf2f04dbfb83b0f98fe92.pdf} } @article { author = {Pourzeynali, S. and hoseinzadeh, mohamad}, title = {An Investigation on the Parameters Influencing the Pounding in Highway Bridges}, journal = {International Journal of Engineering}, volume = {30}, number = {9}, pages = {1298-1308}, year = {2017}, publisher = {Materials and Energy Research Center}, issn = {1025-2495}, eissn = {1735-9244}, doi = {}, abstract = {The present aim of this study is to investigate the effect of different parameters influencing pounding in highway bridges. Pounding is the result of a collision between two parts of the deck and/or the deck and abutments at the separation distance during the earthquake.  In the present study, the period ratio of the adjacent frames, ground motion spatial variation, and soil-structure interaction were considered as the significant parameters influencing the pounding. Accordingly, 144 different models of bridge were generated by changing characteristics of the piers and spans length, and were subjected to non-linear dynamic analysis. The results indicated that ignoring the effects of soil-structure interaction and ground motion spatial variation led to calculate unrealistic responses in the bridges. Finally, it is found that designing bridges including frames with similar or close period is not regarded as an appropriate solution to reduce the pounding effects in the bridges.}, keywords = {bridge,pounding,Ground motion spatial variation,Soil,structure interaction}, url = {https://www.ije.ir/article_73009.html}, eprint = {https://www.ije.ir/article_73009_e8821981e4d93b753d45b1f65a5b4cc4.pdf} } @article { author = {Showkati, Hossein and Rastgar, Mehdi}, title = {Field Study and Evaluation of Buckling Behavior of Cylindrical Steel Tanks with Geometric Imperfections under Uniform External Pressure}, journal = {International Journal of Engineering}, volume = {30}, number = {9}, pages = {1309-1318}, year = {2017}, publisher = {Materials and Energy Research Center}, issn = {1025-2495}, eissn = {1735-9244}, doi = {}, abstract = {Construction and assembling process of shell structures has caused main problems. In these structures, there is no possibility for the integrated construction due to their large shell extent and they are built using a number of welded curved panel parts; hence, some geometrical imperfections emerge. Most of these imperfections are caused by the process of welding, transportation, inappropriate rolling, as well as installation and implementation problems. In this research, construction of steel cylindrical tanks in one of the refinery site is monitored using a field survey and created imperfections are identified and introduced. Relying on the statistical inference, they are classified and then, by studying the effective factors and origin in their generation, the common imperfections are identified. The impact of common imperfections on the buckling behavior is experimentally evaluated under uniform external pressure. Then, nonlinear analysis of the test specimens are performed by ANSYS software. Finally experimental results, finite element and analytical relations are compared. The obtained results show that the imperfections have a direct impact on the structural behavior of shells during the buckling under uniform external pressure load. Also, some imperfections caused by welding increase the buckling resistance of cylindrical shells.}, keywords = {field study,buckling behavior,external pressure,Cylindrical tank,geometric imperfection}, url = {https://www.ije.ir/article_73010.html}, eprint = {https://www.ije.ir/article_73010_b74691b01d65ffe43395c4ebe3d1fc65.pdf} } @article { author = {moradinezhad, Reza and Ghasemi, Jamal and hosseini, Mir Amin}, title = {Kinematic Synthesis of Parallel Manipulator via Neural Network Approach}, journal = {International Journal of Engineering}, volume = {30}, number = {9}, pages = {1319-1325}, year = {2017}, publisher = {Materials and Energy Research Center}, issn = {1025-2495}, eissn = {1735-9244}, doi = {}, abstract = {In this research, Artificial Neural Networks (ANNs) have been used as a powerful tool to solve the inverse kinematic equations of a parallel robot. For this purpose, we have developed the kinematic equations of a Tricept parallel kinematic mechanism with two rotational and one translational degrees of freedom (DoF). Using the analytical method, the inverse kinematic equations are solved for specific trajectory, and used as inputs for the applied ANNs. The results of both applied networks (Multi-Layer Perceptron and Redial Basis Function) satisfied the required performance in solving complex inverse kinematics with proper accuracy and speed.}, keywords = {Parallel Robot,Kinematics,Artificial Neural Network}, url = {https://www.ije.ir/article_73011.html}, eprint = {https://www.ije.ir/article_73011_07b1128becac721f3610ea56aadb0714.pdf} } @article { author = {Moaref, Afsoon and Sattari-Naeini, Vahid}, title = {Fuzzy-rough Information Gain Ratio Approach to Filter-wrapper Feature Selection}, journal = {International Journal of Engineering}, volume = {30}, number = {9}, pages = {1326-1333}, year = {2017}, publisher = {Materials and Energy Research Center}, issn = {1025-2495}, eissn = {1735-9244}, doi = {}, abstract = {Feature selection for various applications has been carried out for many years in many different research areas. However, there is a trade-off between finding feature subsets with minimum length and increasing the classification accuracy. In this paper, a filter-wrapper feature selection approach based on fuzzy-rough gain ratio is proposed to tackle this problem. As a search strategy, a modified Ant Colony Optimization (ACO) algorithm is applied on filter phase. ACO has been approved to be a suitable solution in many difficult problems with graph search space such as feature selection. Choosing minimal data reductions among the subsets of features with first and second maximum accuracies is the main contribution of this work. To verify the efficiency of our approach, experiments are performed on 10 well-known UCI data sets. Analysis of the experimental results demonstrates that the proposed approach is able to satisfy two conflicting constraints of feature selection, increasing the classification accuracy as well as decreasing the length of the reduced subsets of features.}, keywords = {Feature selection,Fuzzy Rough Sets,ant colony optimization,Filter,Wrapper Method}, url = {https://www.ije.ir/article_73012.html}, eprint = {https://www.ije.ir/article_73012_4e957573f828bd3ab682531b3adc3ffb.pdf} } @article { author = {Paydar, Mohammad Mahdi and Safaei, Abdulsattar and Safaei, Abdul Sattar}, title = {Buying Group Design Considering the Member’s Interest}, journal = {International Journal of Engineering}, volume = {30}, number = {9}, pages = {1334-1341}, year = {2017}, publisher = {Materials and Energy Research Center}, issn = {1025-2495}, eissn = {1735-9244}, doi = {}, abstract = {Enhancing the speed and competition in an exhibition of services and products motivated the companies to provide high-quality products to the customers. One of the effective strategies to reach these goals is to create working groups. These groups can help the companies to improve the quality and exposure of their services along with reducing the costs. This approach is applicable in the healthcare area as well. Group buying is one of the main strategies that many healthcare institutes are trying to control the costs and quality of their products. In this study, considering the objectives of procurement costs, the distance of drugstores and the member's interest to cooperate in a purchasing group is proposed. To optimize the model objectives simultaneously, the LP-Metric goal programming approach is utilized. Finally, the case study of drug's group buying is presented to show the proposed model effectiveness.}, keywords = {buying group,Healthcare,reducing costs,members interest}, url = {https://www.ije.ir/article_73013.html}, eprint = {https://www.ije.ir/article_73013_b30e815384ce06ccc57df5d9109b6d07.pdf} } @article { author = {Alaei, Reza and Setak, Mostafa}, title = {Selecting Efficient Service-providers in Electric Power Distribution Industry Using Combinatorial Reverse Auction}, journal = {International Journal of Engineering}, volume = {30}, number = {9}, pages = {1342-1351}, year = {2017}, publisher = {Materials and Energy Research Center}, issn = {1025-2495}, eissn = {1735-9244}, doi = {}, abstract = {In this paper, a combinatorial reverse auction mechanism is proposed for selecting the most efficient service-providers for resolving sustained power interruptions in multiple regions of an electric power distribution company’s responsibility area. Through this mechanism, supplying the required service in each region is assigned to only one potential service-provider considering two criteria including cost and service time. So, the corresponding winner determination problem of the proposed auction mechanism is formulated as a bi-objective combinatorial optimization problem. However, finding a feasible solution for the formulated problem as well as its solving is NP-complete. Since exact optimization algorithms are failed in solving this kind of problems in a reasonable time, a problem specific metaheuristic called NSGA-II that is an evolutionary algorithm for solving multi-objective optimization problems is developed to estimate the set of Pareto optimal solutions of the formulated bi-objective winner determination problem. In our developed NSGA-II, two problem-specific operators are proposed for creating initial feasible solutions and converting infeasible solutions to feasible ones. Furthermore, a new method for determining the population size based on the size of problem instance is proposed. We conduct a computational experiment in which several randomly generated problem instances are solved using the proposed NSGA-II in different settings. Computational results of proposed algorithm in different settings are compared using a quality measure and statistical hypothesis tests. The results of performance comparison show that the proposed NSGA-II with a population size determined by proposed method and a different form of binary tournament method performs better in finding non-dominated solutions for different instances of formulated bi-objective optimization problem.}, keywords = {Supplier selection,electric power distribution industry,combinatorial reverse auction,winner determination problem,multi,objective optimization,NSGA,II}, url = {https://www.ije.ir/article_73014.html}, eprint = {https://www.ije.ir/article_73014_c862c971d649c85f3a439519fcf830c4.pdf} } @article { author = {Dorfeshan, Y. and vahdani, behnam and Mohagheghi, V. and Mousavi, S.M.}, title = {Solving Critical Path Problem in Project Network by a New Enhanced Multi-objective Optimization of Simple Ratio Analysis Approach with Interval Type-2 Fuzzy Sets}, journal = {International Journal of Engineering}, volume = {30}, number = {9}, pages = {1352-1361}, year = {2017}, publisher = {Materials and Energy Research Center}, issn = {1025-2495}, eissn = {1735-9244}, doi = {}, abstract = {Decision making is an important issue in business and project management that assists finding the optimal alternative from a number of feasible alternatives. Decision making requires adequate consideration of uncertainty in projects. In this paper, in order to address uncertainty of project environments, interval type-2 fuzzy sets (IT2FSs) are used. In other words, the rating of each alternative and weight of each criterion are expressed by IT2FSs. Moreover, for obtaining weights of criteria, interval type-2 fuzzy analytic hierarchy process (AHP) method is employed. In addition, a new enhanced model of multi-objective optimization on the basis of simple ratio analysis (MOOSRA) method is developed with IT2F-relative preference relation. Finally, to illustrate applicability of the introduced approach, an existing application from literature is adopted and solved.}, keywords = {Project critical path problem,Relative preference relation,Interval type,2 fuzzy sets (IT2FSs),MOOSRA method}, url = {https://www.ije.ir/article_73015.html}, eprint = {https://www.ije.ir/article_73015_4267ac0efda17ac0ca1f9d07c6702507.pdf} } @article { author = {Mozdgir, Ashkan and Shafaei, Rasoul}, title = {Case Mix Planning using The Technique for Order of Preference by Similarity to Ideal Solution and Robust Estimation: a Case Study}, journal = {International Journal of Engineering}, volume = {30}, number = {9}, pages = {1362-1371}, year = {2017}, publisher = {Materials and Energy Research Center}, issn = {1025-2495}, eissn = {1735-9244}, doi = {}, abstract = {Management of surgery units and operating room (OR) play key roles in optimizing the utilization of hospitals. On this line Case Mix Planning (CMP) is normally applied to long term planning of OR. This refers to allocating OR time to each patient’s group. In this paper a mathematical model is applied to optimize the allocation of OR time among surgical groups. In addition, another technique is applied to provide an Order of Preference by Similarity to Ideal Solution (TOPSIS) considering different hospital performance measures. Furthermore, robust estimation approach is used to estimate the models' parameters using real data. The proposed model is solved using GAMS software. The results of the study performed in this paper reveal that the proposed methods results in an increase in total hospital operated “value of patients” by 21.5%. This value is defined according to hospital priority and includes moral and ethical considerations. In addition, for each resource, a sensitivity analysis of the findings to the changes is conducted. The results of the sensitivity analysis indicated that the value of the objective function significantly increased via reallocating OR time to surgical groups and/or enhancing the OR facilities to support more surgical specialties.}, keywords = {Case mix planning problem,mathematical programming,TOPSIS,Sensitivity analysis,robust estimation}, url = {https://www.ije.ir/article_73016.html}, eprint = {https://www.ije.ir/article_73016_325145c592b051520e7271189e239259.pdf} } @article { author = {Bayati, Nasrin and Kabiri naeini, Mehdi}, title = {Pattern Recognition in Control Chart Using Neural Network based on a New Statistical Feature}, journal = {International Journal of Engineering}, volume = {30}, number = {9}, pages = {1372-1380}, year = {2017}, publisher = {Materials and Energy Research Center}, issn = {1025-2495}, eissn = {1735-9244}, doi = {}, abstract = {Today for the expedition of the identification and timely correction of process deviations, it is necessary to use advanced techniques to minimize the costs of production of defective products. In this way control charts as one of the important tools for the statistical process control in combination with modern tools such as artificial neural networks have been used. The artificial neural networks were used to recognize the pattern in control charts in several research. Two procedures were used based on the raw data and feature for training and application of neural network. This paper presented new statistical features besides the investigation of their efficiency by application of a neural network. The simulation results demonstrated the positive effect of the presented statistical feature on neural network performance.}, keywords = {Control chart. Pattern recognition. Neural network. Statistical feature}, url = {https://www.ije.ir/article_73017.html}, eprint = {https://www.ije.ir/article_73017_97ea8d11950d12286e48d77d8dfd6040.pdf} } @article { author = {Ezzatneshan, Eslam}, title = {Implementation of D3Q19 Lattice Boltzmann Method with a Curved Wall Boundary Condition for Simulation of Practical Flow Problems}, journal = {International Journal of Engineering}, volume = {30}, number = {9}, pages = {1381-1390}, year = {2017}, publisher = {Materials and Energy Research Center}, issn = {1025-2495}, eissn = {1735-9244}, doi = {}, abstract = {In this paper, implementation of an extended form of a no-slip wall boundary condition is presented for the three-dimensional (3-D) lattice Boltzmann method (LBM) for solving the incompressible fluid flows with complex geometries. The boundary condition is based on the off-lattice scheme with a polynomial interpolation which is used to reconstruct the curved or irregular wall boundary on the neighboring lattice nodes. This treatment improves the computational efficiency of the solution algorithm to handle complex geometries and provides much better accuracy comparing with the staircase approximation of bounce-back method. The efficiency and accuracy of the numerical approach presented are examined by computing the fluid flows around the geometries with curved or irregular walls. Three test cases considered herein for validating the present computations are the flow calculation around the NACA0012 wing section and through the two different porous media in various flow conditions. The study shows the present computational technique based on the implementation of the three-dimensional Lattice Boltzmann method with the employed curved wall boundary condition is robust and efficient for solving laminar flows with practical geometries and also accurate enough to predict the flow properties used for engineering designs.}, keywords = {Three,dimensional lattice Boltzmann method,irregular wall boundary condition,laminar fluid flows,complex geometries}, url = {https://www.ije.ir/article_73018.html}, eprint = {https://www.ije.ir/article_73018_4aa80d12e64f0d9a27150908b4f7d463.pdf} } @article { author = {Askari Lasaki, Salar}, title = {Oil Reservoirs Classification Using Fuzzy Clustering (RESEARCH NOTE)}, journal = {International Journal of Engineering}, volume = {30}, number = {9}, pages = {1391-1400}, year = {2017}, publisher = {Materials and Energy Research Center}, issn = {1025-2495}, eissn = {1735-9244}, doi = {}, abstract = {Enhanced Oil Recovery (EOR) is a well-known method to increase oil production from oil reservoirs. Applying EOR to a new reservoir is a costly and time consuming process. Incorporating available knowledge of oil reservoirs in the EOR process eliminates these costs and saves operational time and work. This work presents a universal method to apply EOR to reservoirs based on the available data by clustering the data into compact and well-separated groups. A label is then assigned to each cluster which is in fact class of the data points belonging to that cluster. When EOR is intended to be applied to a new reservoir, class of the reservoir is determined and then EOR method used for the reservoirs of that class is applied to this one with no further field studies and operations. In contrast to classification, clustering is unsupervised and number of clusters within the data is not known a priori. Some well-known methods for determining number of clusters are tried but they failed. A novel method is presented in this work for number of clusters based on difference of membership grades of the data points in the clusters. It is applied to both synthetic and real life data including reservoirs data and it is shown that this method finds number of clusters accurately. It is also shown the raw data could be easily represented as fuzzy rule-base for better understanding and interpretation of the data.}, keywords = {Enhanced oil recovery (EOR),Oil Reservoirs,Fuzzy C,means (FCM),Fuzzy Clustering,outlier,possibilistic c,means (PCM)}, url = {https://www.ije.ir/article_73019.html}, eprint = {https://www.ije.ir/article_73019_3d6b35c89c850add7e420afcc6c2bc08.pdf} } @article { author = {Jozvaziri, Mohammad Ali and Mostofizadeh, Ali Reza and Dehghan Manshadi, Mojtaba}, title = {Parametric Study of Movement Path in Two-dimensional Wing Flow Separation: Experimental Investigation}, journal = {International Journal of Engineering}, volume = {30}, number = {9}, pages = {1401-1407}, year = {2017}, publisher = {Materials and Energy Research Center}, issn = {1025-2495}, eissn = {1735-9244}, doi = {}, abstract = {The aim of this experimental study is two-dimensional investigation of cargo behavior after separation which is carried out in the subsonic wind tunnel. Given that the real separation occurs in three-dimension, the results of this study may be widely used in numerical aerodynamic studies for verification of new computational methods and they can be used as the reference results in this area. So a mechanism has been used which is simulated in two-dimensional physic with three degrees of freedom (x, y, θ) in the subsonic wind tunnel. A wing with NACA0012 airfoil as well as two circular disks at both ends (to simulate two-dimensional flow) have been utilized and separated from the upper surface of the test chamber. For parametric study, the tests have been experimented in the initial attack angles of -10 to +10 degrees with step of 5 degrees at velocity of 15 m/s and at velocities of 10, 15 and 20 m/s at zero degree initial angle of attack. Each test has been repeated 3 times and if there were any differences in the results, the number of repetitions have been increased. To extract the result, several cameras have been installed around the test chamber which take pictures with high-speed shooting. Then, using image processing techniques, x, y, and θ diagrams have been extracted over the time.}, keywords = {Experimental data,Cargo Separation,NACA0012}, url = {https://www.ije.ir/article_73020.html}, eprint = {https://www.ije.ir/article_73020_b57a27a947e29a66acf6f8dc159f8491.pdf} } @article { author = {Varmazyar, Mostafa}, title = {Buoyancy Term Evolution in the Multi Relaxation Time Model of Lattice Boltzmann Method with Variable Thermal Conductivity Using a Modified Set of Boundary Conditions}, journal = {International Journal of Engineering}, volume = {30}, number = {9}, pages = {1408-1416}, year = {2017}, publisher = {Materials and Energy Research Center}, issn = {1025-2495}, eissn = {1735-9244}, doi = {}, abstract = {During the last few years, a number of numerical boundary condition schemes have been used to study various aspects of the no-slip wall condition using the lattice Boltzmann method. In this paper, a modified boundary condition method is employed to simulate the no-slip wall condition in the presence of the body force term near the wall. These conditions are based on the idea of the bounce-back of the non-equilibrium distribution. The error associated with the modified model is smaller than those of other boundary condition models available in the literature. Additionally, various schemes to simulate body forces have been studied. Based on the numerical results, the model demonstrating minimum error has been reported. Finally, it has been shown that the present model is capable of simulating the effect of high nonlinearity in the heat transfer equation in the presence of a variable thermal conductivity. This has been accomplished by employing a multi relaxation time scheme to model a Rayleigh-Benard natural convection current in a 2-D domain with high Rayleigh numbers. Previous studies reported that the onset of oscillation occurs at Ra≈30,000 and Pr=6.0. By the modified boundary condition method which is used in this study, the oscillation is removed until at least Ra≈ 45,000 and Pr=6.0. The results show that applying scheme 3 for the current boundary condition yields the least amount of error compared to the semi-empirical correlation. The Rayleigh-Benard convection problem has been revisited in the presence of a variable thermal conductivity and the simulation results remain stable for flows with a large variation of thermal conductivity ( = 0.7) and Rayleigh numbers up to 1,000,000 and Pr=0.7.}, keywords = {Lattice Boltzmann Method,Boundary condition,Multi Relaxation Time,Variable Thermal Conductivity,Rayleigh,Benard Convection}, url = {https://www.ije.ir/article_73021.html}, eprint = {https://www.ije.ir/article_73021_74cd84fa7643aabede6e2324ff751ac1.pdf} }