List of Articles

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  1 - Characterization of some distributions by inequalities on failure rate
  M. Rajaei Salmasi
  Characterizing distributions is the process of finding the unique properties that distinguish a particular distribution from others. There are various methods for doing this, such as using moments, maximum entropy, hazard rate, and so on. Nanda (2010) used failure rate More

  Characterizing distributions is the process of finding the unique properties that distinguish a particular distribution from others. There are various methods for doing this, such as using moments, maximum entropy, hazard rate, and so on. Nanda (2010) used failure rate and mean residual life functions to characterizing some distributions. In this paper, we extend the results of Nanda (2010). We characterize the Pareto, exponential, and Rayleigh distributions by refining the main results of that paper. We take some inequalities from that paper and propose a new inequality. Then, we raise both sides of the inequalities to some power and show that equality holds if and only if certain distributions are characterized. Manuscript profile
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  2 - Vibration ‎A‎nalysis of a ‎C‎urrent-Carrying Wire in a Magnetic Field Apllying Variational Iteration ‎Method
  M. Hosseini
  In the present investigation, Variational Iteration Method (VIM) is applied to solve the dynamic oscillation of a current-carrying wire in a magnetic field which is generated by a fixed current-carrying conductor parallel to the wire. Two linear springs are considered t More

  In the present investigation, Variational Iteration Method (VIM) is applied to solve the dynamic oscillation of a current-carrying wire in a magnetic field which is generated by a fixed current-carrying conductor parallel to the wire. Two linear springs are considered to restrict the wire to a rigid wall. In a special case, the periodic solution of the problem is obtained by VIM and compared with numerical solutions for different parameters. Results indicate high accuracy of this method which can be easily extended to solve other non-linear vibration equations, therefore can be applicable in other engineering problems. Manuscript profile
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  3 - An Inverse Dynamic FDH Approach to Estimate Outputs
  F. Asadi S. Kordrostami AR. Amirteimoori M. Bazrafshan
  In many situations, the performance and the changes of outputs related to dynamic systems should be estimated while the convexity property is relaxed. Accordingly, first, a dynamic free disposal hull (FDH) model is proposed in this paper to address the efficiency of pro More

  In many situations, the performance and the changes of outputs related to dynamic systems should be estimated while the convexity property is relaxed. Accordingly, first, a dynamic free disposal hull (FDH) model is proposed in this paper to address the efficiency of processes in multiple period of time while the convexity assumption is unsatisfied. Also, two problems, including a mixed integer linear programming and a linear programming model are provided to compute the dynamic FDH model that is a mixed integer non-linear programming problem. Then the changes of multi-period outputs are dealt with for changes of inputs related to several periods using the proposed inverse dynamic FDH model while the efficiency levels are preserved. A case study of gas industry is, moreover, presented to demonstrate the introduced models. The results show the proposed technique is useful to analyze the performance and to estimate outputs in dynamic processes without including convexity. Manuscript profile