Time filter

Source Type

Sahebalam A.,Ferdowsi University of Mashhad | Kashefi M.,Ferdowsi University of Mashhad | Kahrobaee S.,Sadjad Institute of Higher Education
Nondestructive Testing and Evaluation | Year: 2014

The present paper describes details of the comparison on the capability of eddy current (EC) and magnetic Barkhausen noise (MBN) techniques in the assessment of different microstructures in mild steel. To produce various microstructures, AISI 1045 steel samples were subjected to different heat treatment processes including annealing, normalising, quenching and tempering. EC outputs (induced voltage, normalised impedance and phase angle) as well as MBN outputs (peak width, position and amplitude) were evaluated. Comparing the EC/MBN outputs for the microstructures, the MBN peak characteristics show better agreement with changes in the microstructures. Besides, using regression analysis, peak width has been proved to be the optimum output to separate the microstructures with high accuracy. © 2014 Taylor & Francis. Source

Kolahan F.,Ferdowsi University of Mashhad | Doughabadi M.H.,Sadjad Institute of Higher Education
Advanced Materials Research | Year: 2012

Genetic algorithm (GA) is a meta-heuristic inspired by the efficiency of natural selection in biological evolution. It is one of the most widely used optimization procedure which has successfully been applied on a variety of complex combinatorial problems. The main drawback of GA, however, is its several tuning variables which need to be correctly set. The performance of GA largely depends on the proper selection of its parameters values; including crossover mechanism, probability of crossover, population size and mutation rate and selection percent. The objective of this research is to evaluate the effects of tuning parameters on the performance of genetic algorithm using the data collected as per Central Composite Design (CCD) matrix. To gather the required data, the proposed approach is implemented on a well-known travelling salesman problem with 48 cities. Then, regression modeling has been employed to relate GA variables settings to its performance characteristic. Analysis of Variance (ANOVA) results indicate that the function can properly represent the relationship between GA important variables and its performance measure (solution quality). © (2012) Trans Tech Publications, Switzerland. Source

Shariati S.,Sadjad Institute of Higher Education | Haghighi M.M.,University of Western Ontario
2010 International Conference on Computer Information Systems and Industrial Management Applications, CISIM 2010 | Year: 2010

In this paper we use self organized fuzzy system to diagnosis and prognosis hepatitis and thyroid diseases. Moreover, we compare the result of fuzzy Neural Networks with Support Vector Machine(SVM) and artificial neural networks. In addition to diagnosis of disease, we identify the type and the phase of disease via the networks which include six classes for hepatitis disease, namely: hepatitis B (two phase) Hepatitis C (two phase), non-viral hepatitis and non-hepatitis and for thyroid disease we determine five classes, namely: Hypothyroid, Hyperthyroid, Sub-clinical hypothyroid, Sub-clinical hyperthyroid and No thyroid. The performance of each of them has studied and the best method is selected for each of classification tasks. The overall accuracy of diagnosis systems are improved as compared with previously published papers. For hepatitis disease the best accuracies range from 97.6% to 98.77% and for thyroid disease from 95.4% to 99.5%. ©2010 IEEE. Source

Bazzaz Bonabi S.,Semnan University | Kahani Khabushan J.,Semnan University | Kahani R.,Sadjad Institute of Higher Education | Honarbakhsh Raouf A.,Semnan University
Materials and Design | Year: 2014

Composite metal foam was produced as an advanced porous material, using gravity casting technique. Light Expanded Clay Aggregate "LECA" was used as space holder for the produced composite metal foam. The used LECA density was 0.33-0.43g/cm3 and the volume fraction of its porosity was from 73 to 88vol.% and aluminum A355.0 was selected as matrix in order to produce the composite foam. Structural characterization, relative density, hardness and compressive test were studied. The composite metal foam was well investigated and found to have homogeneous structure, relatively equal pore, distributable pore and isotropy properties. The study resulted in that relative density, yield strength and energy absorption capacity were 0.44, 35.9MPa and 18MJ/m3, respectively. © 2014 Elsevier Ltd. Source

Karim M.R.,University of Malaya | Dehghani A.,Sadjad Institute of Higher Education
International Journal of Physical Sciences | Year: 2010

Video and image processing has been used for traffic surveillance, analysis and monitoring of traffic conditions in many cities and urban areas. This paper aims to present another approach to estimate the vehicles velocity. In this study, the captured traffic movies are collected with a stationary camera which is mounted on a freeway. The camera was calibrated based on geometrical equations that were supported directly by using references. Camera calibration for exact measurements may be possible while accurate speed estimation can still be quite difficult to achieve. The designed system has the ability to be extended to another related traffic application. The average error of the detected vehicle speed was ± 7 km/h and the experiment was operated at different resolutions and different video sequences. © 2010 Academic Journals. Source

Discover hidden collaborations