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2004 International Symposium on Distributed Computing and Applications to Business, Engineering and Science

作者： Wang Jingyang,Wang Jianxia,Zhang Xiaoming,Qin Min,Fu Dong College of Information Science & Engineering,Hebei University of Science and Technology Shijiazhuang Hebei 050054,China

This article introduces Java Remote Method Invocation(RMI) architecture,principle and the main steps of developing distributed Java programs with *** present a method of creating distributed programming with Java RMI based on JDBC(Java Database Connectivity) to manipulate blobs (Binary Large Objects) stored in database,illustrate the working principle and working process of the method,and provide an example manipulating blobs stored in Oracle's LONG RAW field.

关键词： Java RMI Manuscript Distributed Programming blobs JDBC

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Thermo-mechanical model of the mantle wedge in Central Mexican subduction zone and a blob tracing approach for the magma transport

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PHYSICS OF THE EARTH AND PLANETARY INTERIORS 2005年第1-2期149卷 165-186页

作者： Manea, VC Manea, M Kostoglodov, V Sewell, G Univ Nacl Autonoma Mexico Inst Geofis Circuito Inv Cientif Mexico City 04510 DF Mexico Univ Texas UTEP Dept Math El Paso TX 79968 USA

The origin of the Central Mexican Volcanic Belt (CMVB) and the influence of the subducting Cocos plate on the CMVB volcanism are still controversial. In this study, the temperature and mantle wedge flow models for the Mexican subduction zone are developed using the finite element method to investigate the thermal structure below CMVB. The numerical scheme solves a system of 2D Stokes equations and 2D steady-state heat transfer equation. Two models are considered for the mantle wedge: the first one with an isoviscous mantle wedge and the second one with strong temperature-dependent viscosity. The first model reveals a maximum temperature of similar to 830 degrees C in the mantle wedge, which is not sufficient for melting of wet peridotite. Also, the geotherm of the subducting plate upper surface does not intersect the dehydration-melting solidus for mafic minerals. The second model predicts temperatures of more than 1200 degrees C beneath the CMVB for a wide range of rheological parameters (reference viscosity and activation energy). Up to 0.6 wt.% H2O can be released down to 60 km depth through metamorphic changes in the oceanic crust of the subducting slab. The melting of this oceanic crust apparently occurs in a narrow depth range of 50-60 kin and also melting of the mantle wedge hydrated peridotite is now expected to take place beneath CNVB. Considering that the melting processes on and in the vicinity of the subducting plate surface generate the most of the volcanic material, a dynamic model for the blob tracers is developed using Stokes flow at infinite Prandtl number. The blobs of 0.2-10.0 km in diameter migrate along very different trajectories only at low wrapping viscosities (n(W) = 10(14)-5 x 10(17) Pa s). The modeling results show that the "fast" trajectories terminate at the same focus location at the base of the continental crust, while the arrival points of "slow" trajectories, which are common for the blobs of smaller size (similar to 0.4-0.5 km), are

关键词： Mexican subduction zone thermal models mantle wedge flow blobs

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Implicit surface visualization of reconstructed biological molecules

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THEORETICAL COMPUTER SCIENCE 2005年第2-3期346卷 281-299页

作者： Garduño, E Herman, GT Univ Calif San Diego Natl Ctr Microscopy & Imagimg Res San Diego CA 92103 USA CUNY Grad Sch Dept Comp Sci New York NY 10036 USA

An implicit surface of a density function is the set of points at which the value of the function is equal to a fixed threshold. An object that is defined as the collection of points at which the density function value is above the threshold can be visualized by displaying the implicit surface. Some methods for the reconstruction of biological macromolecules from their electron microscopic projections produce density functions that are specified by a linear combination of smoothly-varying radially-symmetric basis functions of finite support, also known as blobs. When density functions are determined by such a blob representation, the implicit surfaces are smoothly varying and the normal at any point on such a surface can be analytically calculated. This property can be utilized to produce high-quality visualizations by raycasting. While raycasting tends to be computationally expensive, we present a methodology that uses techniques of computer graphics and image processing to significantly reduce the cost of visualization. (c) 2005 Elsevier B.V. All rights reserved.

关键词： implicit surfaces body-centered cubic grid spherically symmetric basis functions generalized Kaiser-Bessel functions blobs algebraic reconstruction techniques raycasting

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Objects based change detection in a pair of gray-level images

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PATTERN RECOGNITION 2005年第11期38卷 1976-1992页

作者： Miller, O Pikaz, A Averbuch, A Tel Aviv Univ Sch Comp Sci IL-69978 Tel Aviv Israel

The goal of the presented change detection algorithm is to extract objects that appear in only one of two input images. A typical application is surveillance, where a scene is captured at different times of the day or even on different days. In this paper we assume that there may be a significant noise or illumination differences between the input images. For example, one image may be captured in daylight while the other was captured during night with an infrared device. By using a connectivity analysis along gray-level technique, we extract significant blobs from both images. All the extracted blobs are candidates to be classified as changes or part of a change. Then, the candidate blobs from both images are matched. A blob from one image that does not satisfy the matching criteria with its corresponding blob from the other image is considered as an object of change. The algorithm was found to be reliable, fast, accurate, and robust even under extreme changes in illumination and some distortion of the images. The performance of the algorithm is demonstrated using real images. The worst-case time complexity of the algorithm is almost linear in the image size. Therefore, it is suitable for real-time applications. (c) 2004 Published by Elsevier Ltd on behalf of Pattern Recognition Society.

关键词： object extraction blobs matching process boundary distribution illumination independent

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Lemniscates 3D: a CAGD primitive?

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NUMERICAL ALGORITHMS 2005年第1-3期39卷 317-327页

作者： Paluszny, M Montilla, G Ortega, JR Cent Univ Venezuela Lab Computac Grafica & Geometria Aplicada Escuela Matemat Fac Ciencias Caracas Venezuela

A 3D lemniscate is an implicitly given surface which generalizes the well-known Bernoulli lemniscates curves and the Cassini ovals in 2D. It is characterized by placing a finite number of points in space (the foci) and choosing a constant (radius), its algebraic degree is twice the number of foci and it is always contained in the union of certain spheres centered at the foci. The distribution of the foci gives a rough idea of the 3D shapes that could be modeled with any of the connected components of the lemniscate. The position of the foci can be used to stretch and to produce knoblike features. Given a set of foci, for a small radius the lemniscate consists of a number of spherelike surfaces centered at the foci which do not touch each other. As the radius increases the disconnected pieces coalesce producing interesting surfaces. In order to make 3D lemniscates a potentially useful primitive for CAGD it is necessary to control the coalescing/splitting of the connected components of the lemniscate while we move the foci and change the radius, simultaneously. In this paper we offer tools towards this control. We look closely at the case of four noncoplanar foci.

关键词： lemniscate surface deformation foci Cassini ovals blobs

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Reconstruction of velocity distribution of density bursts by wavelet analysis in the linear divertor simulator NAGDIS-II

Reconstruction of velocity distribution of density bursts by...

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9th International Workshop on Plasma Edge Theory in Fusion Devices

作者： Ohno, N Budaev, VP Furuta, K Miyoshi, H Takamura, S Nagoya Univ Ctr Integrated Res Sci & Engn Nagoya Aichi 4648603 Japan RRC Kurchatov Inst Nucl Fus Inst Moscow 123182 Russia Nagoya Univ Grad Sch Engn Dept Energy Engn & Sci Nagoya Aichi 4648603 Japan

We have investigated the velocity distribution of the intermittent bursty fluctuations in the ion saturation currents observed in the linear divertor plasma simulator, NAGDIS-II. The intermittent bursty signals were analyzed by the wavelet transform with complex Morlet mother wavelet. Analyzing a lot of bursts in the ion saturation currents based on the wavelet cross-correlation gives the velocity distribution function. It is positively skewed at the peripheral region of the plasma column, which means the intermittent bursts mainly propagate toward the wail. The averaged velocity depends on the neutral pressure associated with the transition between the attached and detached plasmas. (C) 2004 WILEY-VCH Verlag GmbH & Co. KG A. Weinheim

关键词： blobs wavelet analysis velocity distribution

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Blob transport in the Tokamak scrape-off-layer

Blob transport in the Tokamak scrape-off-layer

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9th International Workshop on Plasma Edge Theory in Fusion Devices

作者： D'Ippolito, DA Myra, JR Krasheninnikov, SI Yu, GQ Pigarov, AY Lodestar Res Corp Boulder CO USA Univ Calif San Diego La Jolla CA 92093 USA

Recent experimental evidence suggests the importance of fast radial plasma transport in the scrape-off-layer (SOL) of tokamaks. The outward transport appears to be convective rather than diffusive, extends into the far SOL, and can produce significant recycling from the main-chamber walls, partially bypassing the divertor. A plausible theoretical mechanism to explain this phenomenon is the radial transport of "blobs" of locally dense plasma created by turbulent processes. A related process is the inward transport of "holes" of reduced density plasma, which provides a mechanism for rapid inward transport of impurities. The blob model is also consistent with the spatial and temporal intermittency and the non-Gaussian statistics observed in the SOL plasma. This paper reviews the present status of blob theory, including analytic models and simulations, and discusses the preliminary comparisons of the blob model with experimental data. (C) 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

关键词： Tokamak transport SOL convection blobs

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基于数据库的文档管理系统及其在企业中的应用