The Unbalanced Oil and Vinegar scheme (UOV) is a signature scheme based on multivariate quadratic equations. It uses m equations and n variables. A total of v of these are called “vinegar variables”. In this paper, we study its security from several points of view. First, we are able to demonstrate that the constant part of the affine transformation does not contribute to the security of UOV an...

We show that the symmetric product of a flat affine scheme over a commutative ring can be embedded into the quotient by the general linear group of the scheme of commuting matrices. We also prove that the symmetric product of the affine space is isomorphic to the above quotient when the base ring is a characteristic zero field. Over an infinite field of arbitrary characteristic the quotient of ...

RATIONALE AND OBJECTIVES The aim of this study was to investigate whether using a fractal dimension as an objective index (quantitative measure) to assess and control the "visual" or "texture" similarity of reference-image regions selected by a content-based image retrieval (CBIR) scheme would (or would not) affect the performance of the scheme in classification between image regions depicting ...

The demand for a high transmission data rate in 5G leads to the wide application of multi-input, multi-output (MIMO) technique. However, narrow design space mobile phone causes severe unexpected coupling between antenna units and deteriorate system performance dramatically. In this paper, we focus on within MIMO system. Some decoupling techniques are summarized, such as neutralization line, net...

A novel Green’s function-free characteristic modes formulation is introduced in this work. The desired impedance or admittance matrix obtained utilizing and appropriately modifying the versatile finite element method. For purpose, generalized eigenvalue problem of electric magnetic field vector wave equation formulated. In case equation, using Schur complement, system reformulated expressed onl...

The release of image processing techniques make image modification and fakery easier. Image fakery, here, is defined as a process to copy a region of source image and paste it onto the destination image, with some post processing methods applied, such as boundary smoothing, blurring, etc. to make it natural. The most important characteristic of image fakery is object copy and paste. In order to...

We propose a new special identity based signature scheme that make uses of fractal transform and entropy arrangement algorithm to generate the public key string from a biometric measurement of signer. A biometric reading provided by the alleged signer would be enough to verify the signature. The characteristic of this scheme is that When verifier finished the verification on the signature, he c...

In this paper, a finite-time control scheme is presented for stabilization of the satellite chaotic attitude around its equilibrium point when its attitude is confused by a disturbed torque. Controllers and settling time of stabilizaton are obtained, based on the Lyapunov stability theorem and finite-time control scheme. This method is satisfied for any initial condition. Numerical simulations ...