Shape matching plays an important role in many application fields. In this paper, we propose a novel rotation invariant 3D shape descriptor based on Hadamard transform and spherical harmonic transform. In our method, a 3D model is represented as a collection of spherical functions to preserve shape information as much as possible, and the shape similarity is directly defined by the difference o...

Let .s4 = {Al, ... 'An} be a family of sets. The elements X, y E u~=l Ai are called equivalent if for every i, 1:::;; i :::;; n, x E Ai if and only if y E Ai. The equivalence classes are called the atoms of the family d. Rado asked in [ 4] the following question: what is the maximum number f(n, d) of atoms, where the maximum is taken over families of n boxes in the d-dimensional Euclidean space...

A new and fast methodology is discussed as a solution to pinpointing the location of a robot called RobVigil, in a robust way, without environment preparation, even in dynamic scenarios. This solution does not require a high computational power. Firstly, the EKF-SLAM is used to find the location of the vehicle, allowing to map the surrounding area in the 3D space. Afterwards, the constructed ma...

Let H = (V,E) be an r-uniform hypergraph and let F ⊂ 2 . A matching M of H is (α,F)perfect if for each F ∈ F , at least α|F | vertices of F are covered by M . Our main result is a theorem giving sufficient conditions for an r-uniform hypergraph to have a (1− ,F)-perfect matching. As a special case of our theorem we obtain the following result. Let K(n, r) denote the complete r-uniform hypergrap...

This paper deals with approximations of maximum independent sets in non-uniform hypergraphs of low degree. We obtain the first performance ratio that is sublinear in terms of the maximum or average degree of the hypergraph. We extend this to the weighted case and give a O(D̄ log log D̄/ log D̄) bound, where D̄ is the average weighted degree in a hypergraph, matching the best bounds known for the sp...

‎in this paper‎, ‎we study translation invariant surfaces in the‎ ‎3-dimensional heisenberg group $rm nil_3$‎. ‎in particular‎, ‎we‎ ‎completely classify translation invariant surfaces in $rm nil_3$‎ ‎whose position vector $x$ satisfies the equation $delta x = ax$‎, ‎where $delta$ is the laplacian operator of the surface and $a$‎ ‎is a $3 times 3$-real matrix‎.

We present a new block-based motion estimation strategy, which aims a t correctly finding the velocity of picture blocks, even for background blocks in occlusion areas. This tritemporal ME calculates the motion between two pictures, switching the ME reference plane dependent on an occlu.sion detector. \lie also introduce a retimer, which can transform, locally in the picture, motion vectors val...

Computer-generated holograms (CGHs) using multiview images (MVIs) are holograms generated with multiple ordinary cameras. This process typically requires a huge number of cameras arranged at high density. In this paper, we propose a method to improve CGH using MVIs that obtains the MVIs by using voxel models rather than cameras. In the proposed method the voxel model is generated using the shap...

Biometrics has become a “hot” area. Governments are funding research programs focused on biometrics. In this paper the problem of person recognition and verification based on a different biometric application has been addressed. The system is based on the 3DSkull recognition using 3D matching technique, in fact this paper present several bio-metric approaches in order of assign the weak point i...

Applications of nanowires into future generation nanodevices require a complete understanding of the mechanical properties of the nanowires. A great research effort has been made in the past two decades to understand the deformation physics and mechanical behaviors of nanowires, and to interpret the discrepancies between experimental measurements and theoretical predictions. This review focused...