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In this work, a comparative study between Elliptic Fourier and B-spline descriptors is carried out for comparing their efficiency in characterizing the contour shape of image objects. In both cases, the goal is to obtain the least representation error using the fewest possible number of coefficients. With Fourier descriptors, different number of harmonics are used while the remaining ones are set...
In the analysis of field problems, cases with open boundaries often arise. The finite element method, frequently used for the numerical solution of field problems, is naturally adequate for closed boundary problems; however, the definition of infinite elements can overcome such limitation. In this paper, mapped infinite elements are used to solve open boundary field problems defined in terms of a...
Recent approaches have been advocated to learn a movement primitive library from demonstrations by using predefined motion features to identify and extract new movement primitives. In this paper, a new bootstrapping cycle is proposed which builds a suitable movement primitive library by (i) perceiving known primitives in complex trajectories, (ii) learn either new primitives or refines old ones, and...
This paper presents a methodology to find optimal zones in automated storage/ retrieval systems (AS/RS) and derive the performance gain for different operating strategies. One central feature of the described method is the computation of precise results in very short time (less than one second in most cases on standard hardware) for any given rack shape independent of interface alignment. These short...
For focusing reflectors usually paraboloidal and ellipsoidal shapes are used, which are a first degree approximation to an optimal beam transformer. In this paper, the design of such an optimally shaped reflector is described, using basic numerical procedures and common CAD software. The complexity of the described procedure is not much higher than the design of paraboloidal or ellipsoidal reflectors...
The curvature control problem for a class of hyper-redundant robot arms with continuum elements characterized by an elastic backbone system is analyzed. The main parameters of the arm shape as curvature and curvature gradient are estimated. The stability analysis and the resulting controllers are obtained using the concept of boundary geometric control and a weighted state control methods. The proposed...
This paper presents a grasp planner which allows a robot to grasp the constricted parts of objects in our daily life. Even though constricted parts can be grasped more firmly than convex parts, previous planners have not sufficiently focused on grasping this part. We develop techniques for quadric surface approximation, grasp posture generation, and stability evaluation for grasping constricted parts...
The shape and center of mass of a part are crucial parameters to algorithms for planning automated manufacturing tasks. As industrial parts are generally manufactured to tolerances, the shape is subject to variations, which, in turn, also cause variations in the location of the center of mass. Planning algorithms should take into account both types of variation to prevent failure when the resulting...
Automation of object counting in digital images has received significant attention in the last 20 years. Objects under consideration varied from cells, bacteria, trees, fruits, pollen, insects to people. These applications cast light on the importance of shape identification and object counting. We developed an algorithm and methodology for detection of mathematically well-defined shapes and calculated...
We present an alternative derivation of analytical expressions for the coefficients of the perturbative nonlinear pre-compensation algorithm in dispersion-unmanaged regime for arbitrary pulse shapes. We specialize to Nyquist pulse-shapes and show the usefuleness of new formulae through simulations and experiments.
Three-dimensional (3D) endocardium visualization plays an extremely important role in localization and ablation of target areas and can improve the cure rate in computer-aided cardiac surgery. In this paper, we discuss how to reconstruct and update the corresponding endocardium surface model quickly and accurately based on the sparse point cloud that is collected dynamically on the left atrial intima...
A novel affine registration technique is proposed which efficiently handles the partial occlusion problem. The proposed method is working without point wise correspondences or radiometric information's. The aligning transformation is found by solving a system of non-linear equations and minimizing the area of occlusions. Each equation is generated by integrating a non-linear function over the foreground...
The past twenty years has seen the explosion of the "shape zoo": myriad shape representations, each with pros and cons. Of the varied denizens, distance transforms and density function shape representations have proven to be the most utile. Distance transforms inherit the numerous geometric advantages of implicit curve representations while density functions are unmatched in their approach...
The cerebral cortex is folded into gyri and sulci in the brains of higher mammals. Quantitative study of the process by which the cortex folds during brain development is critical to a complete understanding of normal brain development and neuro-developmental disorders. In this work, we propose a new method by which to localise nonlinearities in the cortical folding process, and thereby identify regions...
A new technique for computing the location of each antenna element in a conformal array using general Bézier curves is presented here. More specifically, two cubic polynomial Bézier curves are used to compute the location of each antenna element in a conformal 1×4 phased-array antenna on a wedge- and cylindrical-shaped surface for various bend-angles and radius of curvature values, respectively. The...
Gait recognition is an important problem in video surveillance. Most of the existing approaches have provided good performance, but they are often affected by views. In this regard, we present the piecewise approach method for view estimation before recognizing gait. Given a gait sequence, the silhouettes in a gait cycle are obtained, and the stable head and shoulder models are extracted. The Procrustes...
The transmission of automotive communication-signals in mass production is based mainly on electrical cables used in topologies which do not meet technical schoolbook requirements perfectly. For evaluating their signal quality and their communication robustness time-domain based simulation tools are essential. One of the key elements hereby is an adjustable cable model. Unfortunately real cables show...
For a three-dimensional (3-D) problem, this paper shows that the Babinet Principle (BP) can be seen as a good approximation of Physical Optics (PO) for the shadow radiation. Indeed, an original demonstration of the shadow contour theorem (from Ufimtsev) is given which shows that the shadow component of PO does not depend on the shape of the object, but only on its contour. Moreover, we also show mathematically...
Covering is an important form of data, and covering-based rough sets provide an effective tool to deal with this data. In this paper, we use bipartite graphs to study covering-based rough sets. Firstly, a bipartite graph is constructed through a covering, named bipartite graph associated with a covering. According to a bipartite graph associated with a covering, two equivalent representations of a...
This paper presents a scheme of approximating cylindrical models using convolution surfaces and subdivision surfaces. Firstly, an inverse Catmul-Clark subdivision is utilized to approximate the cylindrical models. Then the subdivided mesh is evolved onto the target convolution surface-based shape to produce a natural blending at branches. The initial inverse subdivision reduce the evolution iterations...
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