The problem of jointly detecting whether a target is present in a scene and, if there is, estimating its state can be viewed as a multi-object estimation problem where there is a maximum of one target. This joint dete...
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To simulate mobile-to-mobile (M2M) Rayleigh fading channels under more realistic scenario of non-isotropic scattering, we propose one deterministic and one stochastic sumof- sinusoids (SoS) based simulation models. Th...
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ISBN:
(纸本)9781605585697
To simulate mobile-to-mobile (M2M) Rayleigh fading channels under more realistic scenario of non-isotropic scattering, we propose one deterministic and one stochastic sumof- sinusoids (SoS) based simulation models. The proposed models extensively consider the distributions of the angle of arrival (AoA) and the angle of departure (AoD), and thus show a good approximation to the desired statistical properties of the reference model. Copyright 2009 ACM.
Rock fractures junctions are important objects for detection of rock fracture. Traditionally, junction detectors are devoted to the step-edge corners. Such corners are usually located using a Laplascian operator (zero...
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Rock fractures junctions are important objects for detection of rock fracture. Traditionally, junction detectors are devoted to the step-edge corners. Such corners are usually located using a Laplascian operator (zero-crossings or extrema) or a curvature measure based on the gradient direction. However, the gradient direction of a line does not exist, and a line junction does not correspond to a zero-crossing of the Laplacian. Consequently, step-edge corner detectors are not suitable for line junctions. Their response to a single line junction is not unique. There are other methods to detect the junction. Most of them find L-shaped corners, but create multiple or no responses for more complex junctions. This paper proposes a robust detection method for gray-level line junction which is called the neighborhood pixel-track algorithm. Examples are provided based on experiments with synthetic and real images. The achieved results demonstrate that such junction detection algorithm can successfully identify T-and Y-junctions, and of degree four X-junctions or more complex intercross of rock fractures.
A layered approach is designed to address many of the real-world problems that an inexpensive lane detection system would encounter. A region of interest is first extracted from the image followed by an enhancement pr...
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A layered approach is designed to address many of the real-world problems that an inexpensive lane detection system would encounter. A region of interest is first extracted from the image followed by an enhancement procedure to manipulate the shape of the lane markers. The extracted region is then converted to binary using an adaptive threshold. A model based line detection system hypothesizes lane position. Finally, an iterated matched filtering scheme estimates the final lane position. The developed system shows good performance when tested on real-world data that contains fluctuating illumination and a variety of traffic conditions.
In this paper, we propose a novel free-form deformation (FFD) technique, RDMS-FFD (Rational DMS-FFD), based on rational DMS-spline volumes. RDMS-FFD inherits some good properties of rational DMS-spline volumes and...
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In this paper, we propose a novel free-form deformation (FFD) technique, RDMS-FFD (Rational DMS-FFD), based on rational DMS-spline volumes. RDMS-FFD inherits some good properties of rational DMS-spline volumes and combines more deformation techniques than previous FFD methods in a consistent framework, such as local deformation, control lattice of arbitrary topology, smooth deformation, multiresolution deformation and direct manipulation of deformation. We first introduce the rational DMS-spline volume by directly generalizing the previous results related to DMS-splines. How to generate a tetrahedral domain that approximates the shape of the object to be deformed is also introduced in this paper. Unlike the traditional FFD techniques, we manipulate the vertices of the tetrahedral domain to achieve deformation results. Our system demonstrates that RDMS-FFD is powerful and intuitive in geometric modeling.
This paper deals with the approximate merging problem of multiple adjacent Bézier curves with dierent degrees by a single Bézier curve,which is a frequently seen problem in *** unified matrix representation ...
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This paper deals with the approximate merging problem of multiple adjacent Bézier curves with dierent degrees by a single Bézier curve,which is a frequently seen problem in *** unified matrix representation for precise merging is presented and the approx-imate merging curve is further derived based on matrix *** at the endpoints of curves is also discussed in the merging *** show that the method in this paper achieves satisfying merging results.
The problem of jointly detecting whether a target is present in a scene and, if there is, estimating its state can be viewed as a multi-object estimation problem where there is a maximum of one target. This joint dete...
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ISBN:
(纸本)9780982443804
The problem of jointly detecting whether a target is present in a scene and, if there is, estimating its state can be viewed as a multi-object estimation problem where there is a maximum of one target. This joint detection and estimation problem can be solved using a special case of the multi-object Bayes filter. In this paper we investigate the joint target detection and estimation problem with forward-backward smoothing and propose a sequential Monte Carlo implementation. Finite Set Statistics not only facilitates the development of appropriate joint detection and estimation filters, but also the direct extension of these filtering solutions to their related smoothing counterparts. Preliminary results indicate that using the smoothing has two distinct advantages over just using filtering: Firstly, we are able to more accurately identify the appearance and disappearance of a target in the scene and secondly, we can provide improved state estimates when the target exists.
The solutions of partial differential equations (PDEs) play a key role in today's real world simulations. Computational Fluid Dynamics (CFD) is an important part of this area, which involves the problem of gas or ...
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The solutions of partial differential equations (PDEs) play a key role in today's real world simulations. Computational Fluid Dynamics (CFD) is an important part of this area, which involves the problem of gas or fluid flow over different obstacles, e.g., air flow around vehicles, buildings, or the flow of water in the oceans. In engineering applications the temporal evolution of non-ideal, compressible fluids is quite often modeled by the system of Navier-Stokes equations. They are a coupled set of nonlinear hyperbolic partial differential equations and form a relatively simple, yet efficient model of compressible fluid dynamics. In the paper the implementation of a CFD on Body Fitted Mesh geometry on the Cell Broadband Engine is described. An arbitrary surface can be more easily simulated on body fitted mesh than on rectangular computation domain.
This paper presents a new computational model for representing the Geographic Space concept, called Irregular Cellular Space, which main goal is supporting the development of multiscale spatially explicit dynamic mode...
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This paper presents a new computational model for representing the Geographic Space concept, called Irregular Cellular Space, which main goal is supporting the development of multiscale spatially explicit dynamic models integrated to geographical databases. This model has been implemented in a modeling software platform named TerraME which has been used for the development of some interesting environmental dynamic models and form simulation of dynamic spatial patterns of change.
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