the stray light or `ghost' analysis of the National Ignition Facility's (NIF) Final Optics Assembly (FOA) has proved to be one of the most complex ghost analyses ever attempted. the NIF FOA consists of a bundl...
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the stray light or `ghost' analysis of the National Ignition Facility's (NIF) Final Optics Assembly (FOA) has proved to be one of the most complex ghost analyses ever attempted. the NIF FOA consists of a bundle of four beam lines that: 1) provides the vacuum seal to the target chamber, 2) converts 1 ω to 3 ω light, 3) focuses the light on the target, 4) separates a fraction of the 3 ω beam for energy diagnostics, 5) separates the three wavelengths to diffract unwanted 1 ω & 2 ω light away from the target, 6) provides spatial beam smoothing, and 7) provides a debris barrier between the target chamber and the switchyard mirrors. the three wavelengths of light and seven optical elements withthree diffractive optic surfaces generate three million ghosts through 4th order. Approximately 24,000 of these ghosts have peak fluence exceeding 1 J/cm2. the shear number of ghost paths requires a visualization method that allows overlapping ghosts on optics and mechanical components to be summed and then mapped to the optical and mechanical component surfaces in 3D space. this paper addresses the following aspects of the NIF Final Optics Ghost analysis: 1) materials issues for stray light mitigation, 2) limitations of current software tools (especially in modeling diffractive optics), 3) computer resource limitations affecting automated coherent raytracing, 4) folding the stray light analysis into the opto-mechanical design process, 5) analysis and visualization tools from simple hand calculations to specialized stray light analysis computer codes, and 6) attempts at visualizing these ghosts using a CAD model and another using a high end data visualization software approach.
this work has two objectives: rst, to introduce rough set theory, developed by Pawlak, to a wider audience;second, to present computational methods for the theory, allowing it to be implemented in many more systems. R...
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the topography of the power system network keeps on changing as the economy of a nation grows and it's power consumption increases. If relays must discriminate adequately between tolerable overload condition and f...
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the topography of the power system network keeps on changing as the economy of a nation grows and it's power consumption increases. If relays must discriminate adequately between tolerable overload condition and fault condition, the power utility company must carry out a thorough short circuit study of the system periodically so as to ensure an effective relaying and switching system. A computersoftware, POSCODAM (Power systems Computing and Data Management), is applied to determine the contingency fault levels in the Electric Power Grid Network of Botswana. the application of the computersoftware enables the load flow and the contingency levels to be determined directly, using current data from the grid system without resorting to reduction of the network the results could be of use to the engineers of the Electric Power Utility Company of Botswana.
this paper describes a fuzzy expert case-based reasoning system. the idea is to combine methodologies from both technologies to come up with a system that utilizes inference procedures with matching algorithms used by...
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this paper describes a fuzzy expert case-based reasoning system. the idea is to combine methodologies from both technologies to come up with a system that utilizes inference procedures with matching algorithms used by case-based reasoning systems. We describe the system and, with examples, show how it can be utilized to solve problems in a more natural way than some of the existing case-based reasoning systems.
Choosing the right abstractions is important for managing the complexity of your system. three important abstractions used today are object, component and agent. Many similarities exist between these abstractions, but...
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the paper presents the computer Aided Design of Distribution Network (CADDiN) application based on geographic information system (GIS) and genetic algorithms designed to improve the planning of major investment in ope...
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the paper presents the computer Aided Design of Distribution Network (CADDiN) application based on geographic information system (GIS) and genetic algorithms designed to improve the planning of major investment in open-loop distribution network over the coming years. the system allows the planner to identify, from load forecast, data on the existing distribution system and all future projects, the projects to be undertaken together withthe commissioning year, in such a way that the investment and maintenance costs, as well as cost of losses are minimized over a planning horizon. the application has been tested with real size distribution systems achieving optimal designs in reasonable CPU times compared with respect to the dimensions of such distribution systems.
Many multimedia applications will be designed to run on heterogeneous computing environments or will be interconnected to offer multimedia services. However multimedia incorporation proves insufficient for training an...
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Many multimedia applications will be designed to run on heterogeneous computing environments or will be interconnected to offer multimedia services. However multimedia incorporation proves insufficient for training and education system implementation. Its a main issue that students or training participants not only conduct and record but also have the possibility to communicate their work in an interactive learning environment. For these reasons our research efforts focus on an agent based control system telesession controller for presentation of education units in open and distributed environments. the paper presents the composition of the telepresentations consisting of different multimedia objects like text, graphics, movies, videos and also nonhypermedia objects such as executable mathematical simulation or design tasks in distributed electronic classrooms. We assume that there exists a computer network which consists of peer to peer connected local area networks. One local network represents one virtual electronic class room. the server in one of these networks plays the specific role of the on-line sender of an education session. Other virtual class rooms are active receivers of the telepresentation session.
Saturating actuators are a major concern in practical control applications. One way of dealing withthis issue is to avoid saturation by slowing down the controller. this paper presents a new switching controller desi...
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Saturating actuators are a major concern in practical control applications. One way of dealing withthis issue is to avoid saturation by slowing down the controller. this paper presents a new switching controller design methodology for a class of uncertain systems subject to input saturation. the scheme allows for up to 100% over-saturation while quadratic stability of the hybrid system is guaranteed. the goal of the method is to use the full authority of the available control.
the paper presents an original approach for visual identification of road direction of an autonomous vehicle using an improved Radial Basis Fimction (RBF) neural network. We present the results of designing, software ...
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the paper describes our approach to adding "stored procedure" capability to a semantic database system using Java byte-codes and Java's ability to dynamically load and execute Java code. Several steps we...
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