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Nikafshan Rad H.,Tabari University of Babol | Jalali Z.,Shahid Bahonar University of Kerman | Jalalifar H.,Shahid Bahonar University of Kerman
International Journal of Rock Mechanics and Mining Sciences | Year: 2015

Survey properties of soil and rock mass have always been associated with uncertainty. Hence, the behavior of the soil or rock cannot be investigated specifically by choosing a value specified for these properties. One of the most common systems for studying properties of rock mass is the rock mass classification system (RMR) which was developed by Bieniawski. In this system the input parameters are divided into several classes, and each class has particular rating. In this system, because of uncertainties of the input parameters, determining the definite boundary between the classes and assigning a specified value to a particular class is difficult, so when the input parameters are close to the boundary between the classes, the class rating with certainity is not decided. The aim of this paper is to propose a hybrid nonlinear Chaotic and Neuro-Fuzzy system modeling for the basic RMR system uncertainty based on continuous functions. This model also proves the theory of Bieniawski that is based on nonlinear systems by using chaos theory and mathematical relations. The main advantage of proposed model is to directly predict output of RMR system classification system without considering the input parameters so that it leads to better results and a higher level of prediction rock quality. © 2014 Elsevier Ltd.

Roodgar M.,Tabari University of Babol | Mahmoudi M.M.,University of Tehran | Ebrahimi P.,Islamic Azad University at Varamin | Molaei D.,K. N. Toosi University of Technology
Procedia Engineering | Year: 2011

Although Green Building is one of the familiar subjects all over the world, it is a recently known field in Iran. This subject has been developed to expand the communications between domestic architecture and foresight in order to protect the environmental and climatic problems. This work generates a detailed comparison between modern and traditional housings by considering sustainability in energy and resource consumptions, architectural topology and green building evaluations in Kashan as a hot-arid region of Iran. The investigation shows results in several designrelated methods which are suitable to contribute as efficient use of energy and domestic resources. Finally, this work puts forward a set of recommendation to enhance the sustainability of future Kashan buildings. © 2011 Published by Elsevier Ltd.

Motameni H.,Islamic Azad University at Sari | Nemati M.,Tabari University of Babol
International Journal of Engineering, Transactions B: Applications | Year: 2014

CRC cards are unconventional methods for identifying and describing classes, behavior and their responsibilities and collaborators of class. Representation of three categories of class, responsibilities and collaborators can give proper image of the scenario. These cards are effective method for analyzing scenarios. With all positive features of CRC cards, these cards have some weaknesses such as failure to show details of operations and failure to evaluate them. These weaknesses guide us to model and evaluate these cards using petri nets. Basis of petri nets is on graph. In addition, these petri nets have mathematical structure and definitions, they have graphics. One of the other important characteristics of petri nets is their applicability which can be used for evaluating behavior and efficiency of a system. Therefore, our goal in this paper is to map CRC cards into stochastic petri net for evaluating and analyzing quality parameter of security.

Abdollahzadeh G.,Babol Noshirvani University of Technology | Faghihmaleki H.,Tabari University of Babol
Journal of Advanced Research in Dynamical and Control Systems | Year: 2014

Major part of existent structures have been designed based on old regulations and, hence, they are not able to respond to the expected operation under the effect of severe earthquakes. In present research, some methods of seismic rehabilitation of steel structures of medium moment frame with braces are studied. In this way, three models of steel medium moment frames (in two directions) with 3, 8 and 12 stories are designed according to old seismic design codes. Next, these models are evaluated on the basis of the seismic provisions for steel structures (ANSI/AISC 341-10). It is noticed that these structures don’t meet the required seismic provisions. Then, the models are rehabilitated by two following methods: (1) by using the Typical Buckling Braces (TBBs) and (2) by using Bucking Restrained Braces (BRBs). Structural models are analyzed in SAP2000 software with nonlinear static and dynamic time history analysis. The seismic responses are discussed in detail to explore pros and cons of the aforementioned strengthening methods. © 2014 Institute of Advanced Scientific Research, Inc.

Salimi R.,Tabari University of Babol | Motameni H.,Islamic Azad University at Sari | Omranpour H.,Tabari University of Babol
Journal of Parallel and Distributed Computing | Year: 2014

Scheduling algorithms have an essential role in computational grids for managing jobs, and assigning them to appropriate resources. An efficient task scheduling algorithm can achieve minimum execution time and maximum resource utilization by providing the load balance between resources in the grid. The superiority of genetic algorithm in the scheduling of tasks has been proven in the literature. In this paper, we improve the famous multi-objective genetic algorithm known as NSGA-II using fuzzy operators to improve quality and performance of task scheduling in the market-based grid environment. Load balancing, Makespan and Price are three important objectives for multi-objective optimization in the task scheduling problem in the grid. Grid users do not attend load balancing in making decision, so it is desirable that all solutions have good load balancing. Thus to decrease computation and ease decision making through the users, we should consider and improve the load balancing problem in the task scheduling indirectly using the fuzzy system without implementing the third objective function. We have used fuzzy operators for this purpose and more quality and variety in Pareto-optimal solutions. Three functions are defined to generate inputs for fuzzy systems. Variance of costs, variance of frequency of involved resources in scheduling and variance of genes values are used to determine probabilities of crossover and mutation intelligently. Variance of frequency of involved resources with cooperation of Makespan objective satisfies load balancing objective indirectly. Variance of genes values and variance of costs are used in the mutation fuzzy system to improve diversity and quality of Pareto optimal front. Our method conducts the algorithm towards best and most appropriate solutions with load balancing in less iteration. The obtained results have proved that our innovative algorithm converges to Pareto-optimal solutions faster and with more quality. © 2014 Elsevier Inc. All rights reserved.

Salmanpour S.,Tabari University of Babol | Motameni H.,Islamic Azad University at Sari
Journal of Intelligent and Fuzzy Systems | Year: 2014

In this paper, the generalized intelligent water drops (IWD) algorithm is proposed to solve robot path planning problem. Path planning is modeled by IWD algorithm, because there is inherent similarity between this and finding most appropriate route in natural rivers, that occurs by interaction between water drops and the river bed. The proposed algorithm has two levels; first level, finds the best global feasible path. Second level, performs local search at relatively near distances of global path and reduces its length and time to reach optimal solution. The IWD algorithm, like other inspired nature algorithms, has not a mechanism to deal with constrained optimization problem in its original version. So, a mechanism has been proposed based on repair of infeasible solutions. In this mechanism, a fuzzy inference system is proposed for selecting the best possible infeasible solution and then the local search operator repairs any of them in violation locations. Another innovation of this paper provides a mechanism to local soil update, which is based on fuzzy systems and is independent of size and complexity of environment and its soil altering will be defined in fixed range. Simulation result shows ability of IWD algorithm in finding of the optimal path.

Shahabi H.,University of Technology Malaysia | Keihanfard S.,Islamic Azad University | Ahmad B.B.,University of Technology Malaysia | Amiri M.J.T.,Tabari University of Babol
Environmental Earth Sciences | Year: 2014

The city of Saqqez has a population of 140,000 people, making it one of the largest cities in Iran. Population growth, consumerism, and change in eating habits, such as the increased use of packaged products, is causing the accumulation of waste in this city to increase. In this study, the selection of a waste landfill site for Saqqez focused on 13 layers of geography information that was used by the IDRISI and Arc GIS software. Different models of the analytic multi-criteria decision-making process, such as an analytical hierarchy process (AHP), weighted linear combination (WLC), and Boolean logic, were used to manage layers to establish specific databases for urban waste landfills. Satellite images (Landsat ETM+ and SPOT 5), proposed sites and a land use map of the study area were also used. The results of this study indicated that two methods (AHP and WLC) in the early stages had better decision-making powers for locating landfill sites when compared to Boolean logic. Overlapping and compounding the similarities between these models in Arc GIS software, a 74-ha site was found. This site will be able to accept 130 tons of waste per day for the next 20 years. © 2013 Springer-Verlag Berlin Heidelberg.

Abdollahzadeh G.,Babol Noshirvani University of Technology | Jahani E.,University of Mazandaran | Kashir Z.,Tabari University of Babol
Computers and Concrete | Year: 2016

This paper, proposes 20 models for predicting compressive strength of recycled aggregate concrete (RAC) containing silica fume by using gene expression programming (GEP). To construct the models, experimental data of 228 specimens produced from 61 different mixtures were collected from the literature. 80% of data sets were used in the training phase and the remained 20% in testing phase. Input variables were arranged in a format of seven input parameters including age of the specimen, cement content, water content, natural aggregates content, recycled aggregates content, silica fume content and amount of superplasticizer. The training and testing showed the models have good conformity with experimental results for predicting the compressive strength of recycled aggregate concrete containing silica fume. © 2016 Techno-Press, Ltd.

Monfared H.,Sharif University of Technology | Salmanpour S.,Tabari University of Babol
Journal of Intelligent and Fuzzy Systems | Year: 2015

In this paper, a generalized intelligent water drops algorithm (IWD) for solving robot path planning problem is proposed. The authors want to reduce the time of reaching the optimal solution as much as possible. To do this, some new heuristic operators and a multi section graph model of environment is introduced. The authors divide graph to equal sections and compare behaviour of the solutions (paths) in each section with behaviour of them in other sections. This comparison uses a fuzzy inference system. Base on this comparison, a fuzzy number is assigned to each part of solutions. This fuzzy number determines the worth of a solution in a section. Less worth solutions need more improvement. New heuristic operators are used in the sections that need more improvement. The runtime of algorithms are increased by using a memory for keep proper solutions and a global smooth operator that smooth the solutions. The authors used proposed memory to apply heuristic operations on proper solutions more than other one. This method helps to obtain more improvement in lower runtime. The authors introduce two intersection operators for robot path planning problem that apply to solutions in memory. Experimental results show that the proposed algorithms find the optimal solutions in fewer runtime rather than other works. © 2015 - IOS Press and the authors.

Bahnamiri S.B.,Tabari University of Babol
Journal of Biomedical Physics and Engineering | Year: 2015

Background: Obtaining high quality images in Single Photon Emission Tomography (SPECT) device is the most important goal in nuclear medicine. Because if image quality is low, the possibility of making a mistake in diagnosing and treating the patient will rise. Studying effective factors in spatial resolution of imaging systems is thus deemed to be vital. One of the most important factors in SPECT imaging in nuclear medicine is the use of an appropriate collimator for a certain radiopharmaceutical feature in order to create the best image as it can be effective in the quantity of Full Width at Half Maximum (FWHM) which is the main parameter in spatial resolution. Method: In this research, the simulation of the detector and collimator of SPECT imaging device, Model HD3 made by Philips Co. and the investigation of important factors on the collimator were carried out using MCNP-4c code. Results: The results of the experimental measurments and simulation calculations revealed a relative difference of less than 5% leading to the confrmation of the accuracy of conducted simulation MCNP code calculation. Conclusion: This is the frst essential step in the design and modelling of new col-limators used for creating high quality images in nuclear medicine. © 2015 Shiraz University of Medical Sciences. All rights reserved.

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