Numerical methods are not always convergent especially in higher velocities when shock waves are involved. A comparison analysis is performed to study the supersonic flow over conical bodies of three different cross sections circular, elliptic and squircle (square with rounded corners) shaped using  Perturbation techniques to find flow variables analytically. In order to find lift and drag forc...

The work is devoted to a new branch of application of continuous group’s techniques in the investigation of nonlinear differential equations. The principal stages of the development of perturbation theory of nonlinear differential equations are considered in short. It is shown that its characteristic features make it possible a fruitful usage of continuous group’s techniques in problems of pert...

Commercial organizations and government agencies that gather, store, share and disseminate data are facing increasing concerns over individual privacy and confidentiality. Confidential data is often masked in the database or prior to release to a third party, through methods such as data perturbation. In this study, reidentification risks of three major additive data perturbation techniques wer...

A singularly perturbed model is proposed for a system comprised of a PEM Fuel Cell(PEM-FC) with Natural Gas Hydrogen Reformer (NG-HR). This eighteenth order system is decomposedinto slow and fast lower order subsystems using singular perturbation techniques that provides tools forseparation and order reduction. Then, three different types of controllers, namely an optimal full-order,a near-opti...

Perturbation methods are mathematical techniques used to add controlled noise or randomness data protect privacy while allowing analysis. Various methods, such as randomized response, differential privacy, secure multi-party computation, addition, and sampling aggregation, sensitive information from disclosure exploitation. These have been successfully applied in machine learning, statistics, c...

The homotopy perturbation method proposed by the present author is further improved in this paper, which is proved to be effective and convenient to solving nonlinear equations. Introduction There exist many difficulties encountered in the application of the traditional perturbation techniques to solving strongly nonlinear equations. Of these, one of the most frustrating is the fact that even a...