Parametric curves such as Bézier and B-splines, originally developedfor the design of automobile bodies, are now also used in image processing andcomputer vision. For example, reconstructing an object shape in an...
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Parametric curves such as Bézier and B-splines, originally developedfor the design of automobile bodies, are now also used in image processing andcomputer vision. For example, reconstructing an object shape in an image,including different translations, scales, and orientations, can be performedusing these parametric curves. For this, Bézier and B-spline curves can be generatedusing a point set that belongs to the outer boundary of the object. Theresulting object shape can be used in computer vision fields, such as searchingand segmentation methods and training machine learning algorithms. Theprerequisite for reconstructing the shape with parametric curves is to obtainsequentially the points in the point set. In this study, a novel algorithm hasbeen developed that sequentially obtains the pixel locations constituting theouter boundary of the object. The proposed algorithm, unlike the methods inthe literature, is implemented using a filter containing weights and an outercircle surrounding the object. In a binary format image, the starting point ofthe tracing is determined using the outer circle, and the next tracing movementand the pixel to be labeled as the boundary point is found by the filter ***, control points that define the curve shape are selected by reducing thenumber of sequential points. Thus, the Bézier and B-spline curve equationsdescribing the shape are obtained using these points. In addition, differenttranslations, scales, and rotations of the object shape are easily provided bychanging the positions of the control points. It has also been shown that themissing part of the object can be completed thanks to the parametric curves.
In this paper, the study aimed to identify the best forecasting model to represent I-Helpdesk, service desk of an Information technology (IT) project under the Singapore's Ministry of defence (MINDEF), in the aspe...
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In order to secure RFID transactions, an authentication scheme has originally been included as part of the "EPC Gen2" industrial standard. This scheme, however, has been found to have some weaknesses. To ove...
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This paper presents a flexible virtual structure (V-S) formation control schemes for nonholonomic fixed-wing UAVs. In contrast to geometric rigid V-S formation control schemes, flexible V-S formation scheme enables a ...
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New components and methods in the field of microwave techniques, electrooptics, computer technology, statistics, and electromagnetics open new and very interesting possibilities with regard to detection and identifica...
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New components and methods in the field of microwave techniques, electrooptics, computer technology, statistics, and electromagnetics open new and very interesting possibilities with regard to detection and identification problems. The current contribution suggests with varying degrees of substantiation a set of unified detection methods which may conceivably have an impact on several application areas (environmental surveillance, detection/identification of specific objects). The basic principle is the following. Most of the existing detection/identification systems do not make optimum use of all the a priori information that one generally is in possession of with regard to the target of interest. Knowing the geometrical shape of the target of interest and its molecular surface structure (e.g., structure of paint), an illumination function can be structured (matched filter concept) which gives optimum system sensitivity (minimum receiver bandwidth) with respect to the target of interest at the expense of the sensitivity for background objects (interferents). Theoretical results are given in the paper for a limited number of geometrical objects and for two different molecular surface compositions. It is shown that the system sensitivity and identification capability can be improved considerably using the suggested matched filter illumination technique. Copyright 1978 by the American Geophysical Union.
In order to secure RFID transactions, an authentication scheme has originally been included as part of the "EPC Gen2" industrial standard. This scheme, however, has been found to have some weaknesses. To ove...
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In order to secure RFID transactions, an authentication scheme has originally been included as part of the "EPC Gen2" industrial standard. This scheme, however, has been found to have some weaknesses. To overcome such weaknesses, some authors have proposed new schemes to improve its security. Two of the latest proposals are the Lim-Li protocol and the Konidala-Kim-Kim protocol presented in 2007. We propose an attack that can be applied to both these protocols. In both cases, the search space for the password(s) used have been drastically reduced, which effectively breaks the security of these protocols.
This paper deals with the implementation of full adder chains by mixing different CMOS full adder topologies. The proposed approach is based on cascading fast Gate Diffusion Input (GDI) Full Adders interrupted by stat...
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The aerospace industry has been identified as a key player in the restructuring of the European defence industry as a whole and the British government has seemed keen to support the role of the UK aerospace industry i...
Ramjets are the preferred air-breathing engines at high supersonic speeds. The combustion phenomenon in ramjet combustors is very complex. The complexities arise due to liquid - gas phase coupling, high temperature va...
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ISBN:
(纸本)1563478188
Ramjets are the preferred air-breathing engines at high supersonic speeds. The combustion phenomenon in ramjet combustors is very complex. The complexities arise due to liquid - gas phase coupling, high temperature variation and intricate flame chemistry. Numerical simulation of flow environment in ramjet combustors is formidably challenging because the flow process comprises simultaneous momentum, heat and mass transport processes. Flow simulation software FLUENT is used to simulate the flow environment in a ramjet dump combustor with two side inlets 90° apart by solving the governing equations with appropriate boundary conditions. The turbulent flow features are predicted by employing standard k - Ε equations based on generalized Boussinesq eddy viscosity concept. Eulerian approach is used to model the gas phase heat and mass transfer. Fuel particles are tracked using Lagrangian formulation. In liquid phase modelling, the momentum, energy and species balances are carried out by treating the droplet as a lumped system. Probability Density Function (PDF) approach is employed to describe the turbulent fluctuations in the mixture fraction. Predictions of temperature inside a ramjet combustor were compared with the limited experimental data available and reasonable matching was observed. A detailed study has been carried out on the baseline combustor geometry under consideration for air/fuel ratios of 10, 15 and 30 and the results are discussed in this paper.
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