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This paper proposes a novel texture based method for visualization of electromagnetic fields. According to the characteristics of electric eddy current fields, a scalar potential is constructed to express the field on the surfaces. Then the potential is used in deducing an extension form of the Sinusoidalfunction Modulated Potential (SMP) image of general surface eddy current fields. The SMP Image can display the distribution of both the direction and amplitude of the field. The paper also presents a new algorithm based on hardware accelerated texture mapping. The algorithm could render the SMP image in real time and can be further used in dynamic visualization of time-varying electromagnetic field. The rendered dynamic images can reflect the variation of the field with space and time simultaneously. The only requirements for the method are that the vector field is distributed on surface and that its divergent is free, which makes the method suitable for visualization of general divergent-free vector field distributed on surface. [ABSTRACT FROM AUTHOR]

This paper studies how the built-in natural weakness in the image processing algorithm or system can be searched and found with the evolutionary algorithms. In this paper, we show how the genetic algorithm finds the weakness in the Bayer's dispersed dot dithering method. We also take a closer look at the method and identify why this weakness is relatively easy to find with synthetic images. Moreover, we discuss the importance of comprehensive testing before the results with some image processing methods are reliable. [ABSTRACT FROM AUTHOR]

An algorithm for alternate pattern fill on arbitrary line segments, circular arcs and elliptical arcs is proposed in this paper. The algorithm creates an external loop which is a minimal loop that contains a given point. And then, all loops that delimit the nested regions for the alternate pattern fill inside the external loop are built. The loop detection is based on a new method for searching the leftmost edges. It requires only values of positions, tangent vectors, curvature radii, and the first derivatives of curvature radii at intersection points and areas of circles and ellipses. After all necessary loops are built, the given pattern is filled in the nested loops inside the external loop. Filling the given pattern in this paper is simplified into filling line segment patterns on some parallel lines. [ABSTRACT FROM AUTHOR]

This paper presents a method to reduce features less contributing to the classification of user preferred news groups among several news groups by the use of fuzzy inference and coefficient of determination. To this end, we extract a number of representative keywords from example documents through fuzzy inference. From the observation of training patterns, we found that lots of keywords in training patterns are empty. Thus, a new method to train neural network through reduction of unnecessary dimensions by the statistical coefficient of determination is proposed in this paper. Experimental results show that the proposed method is superior to the method using lots of input attributes in terms of within-cluster variance and its standard deviation. [ABSTRACT FROM AUTHOR]

In this paper, we compare a well-known semantic spacemodel, Latent Semantic Analysis (LSA) with another model, Hyperspace Analogue to Language (HAL) which is widely used in different area, especially in automatic query refinement. We conduct this comparative analysis to prove our hypothesis that with respect to ability of extracting the lexical information from a corpus of text, LSA is quite similar to HAL. We regard HAL and LSA as black boxes. Through a Pearson's correlation analysis to the outputs of these two black boxes, we conclude that LSA highly co-relates with HAL and thus there is a justification that LSA and HAL can potentially play a similar role in the area of facilitating automatic query refinement. This paper evaluates LSA in a new application area and contributes an effective way to compare different semantic space models. Keywords: Correlation Analysis, Hyperspace Analogue to Language, Latent Semantic Indexing, Automatic Query Refinement. [ABSTRACT FROM AUTHOR]

This paper proposes an approach to data integration and migration from a collection of heterogeneous and independent data sources into a data warehouse schema. Current methodology assumes that the data is loaded into data warehouse using queries in order to extract data from multiple data sources. Extracting data from various data sources requires the establishment of generic data integration methodologies. Sometimes, various data anomalies arise when using complex queries across multiple data sources. A data warehouse can be abstractly seen as a set of materialized views. Selecting views for materialization in a data warehouse is one of the most important decisions making tasks in its design. However, there are few facilities in data integration systems that consider these important issues. In this paper, we propose the approach of introducing staging table's schema that can be utilized to load required data from source tables into corresponding staging tables. Staging tables will be assumed to be temporary tables and each staging table will be empty before loading new data and using simple non-join queries to load data. We then focus on an approach to load data into data warehouse materialized views through staging tables including maintenance of materialized views. Keywords: Data Integration, Data Migration, Staging Tables, Global Schema, and Relational Schema. [ABSTRACT FROM AUTHOR]

Computational Grids, coupling geographically distributed resources, have emerged as a next generation computing platform for solving large-scale problems in scientific arena. Monitoring these Grid computing resources, which not only helps end-users monitor the status of Grid resources, but also provides quick and comprehensive information for resource scheduling and management, becomes extremely important for efficiently using Grid Computing resource. This paper presents architecture and implementation of a Grid Monitoring System based on Globus Toolkit. The Grid Monitoring System presented in this paper is flexible, extensible and, most important, secure. The architecture and implementation presented in this paper has important practical value for the monitoring of China Education and Research Grid. [ABSTRACT FROM AUTHOR]

In this paper, we propose an approach for the real-time performance analysis of distributed programs, called Eidolon. The approach is based on the capacity of communication links. In Eidolon, some algorithms are designed to find all the transmission paths of each data file needed while the program executes, count the transmission time for each the transmission path, then get the minimum and the maximum transmission time by analyzing all the transmission paths of each data file, and at last, calculate the fastest and the slowest response time of distributed programs. A case study is given at the end of this paper to justify the validity of this approach. [ABSTRACT FROM AUTHOR]

In this paper a networked control system (NCS) design problem is discussed where a single digital controller and multiple plants interconnected by a common computer network with transfer time delays. The network-induced delays are assumed to be unknown constant in this paper, and a measuring method for delays in TCP/IP network is proposed to compensate the performance degradation due to the delay effect. An NCS is designed with LQR algorithm and applied to an inverted pendulum accounting for the multiple time delays as a benchmark plant to check its performance under time delays induced by the network. [ABSTRACT FROM AUTHOR]

We propose a novel multicast communications model using a RingNet hierarchy, called the RingNet model, which is a combination of logical trees and logical rings for multicast communications. The RingNet hierarchy consists of four tiers: Border Router Tier (BRT), Access Gateway Tier (AGT), Access Proxy Tier (APT), and Mobile Host Tier (MHT). Within the hierarchy, the upper two tiers are dynamically organized into logical rings with network entities. In this paper, based on the RingNet model, local group concept is proposed. For simple illustration, we choose each AG in AGT as the controller of each local group. Each local group has its own independent local group key. The member's join or leave in a local group only affects the local group, which makes multicast communications potentially scalable to very large groups. In this paper, we propose a novel key management scheme for secure multicast with the RingNet model. [ABSTRACT FROM AUTHOR]

A dual-cube DC(m) has m + 1 links per node where m is the degree of a cluster (m-cube), and one extra link is used for connection between clusters. The dual-cube mitigates the problem of increasing number of links in the large-scale hypercube network while keeps most of the topological properties of the hypercube network. In this paper, we propose efficient algorithms for finding a nonfaulty routing path between any two nonfaulty nodes in the dual-cube with a large number of faulty nodes. A node v ∈ DC(m) is called k-safe if v has at least k nonfaulty neighbors. The DC(m) is called k-safe if every node in DC(m) is k-safe. The first algorithm presented in this paper is an off-line algorithm that uses global information of faulty status. It finds a nonfaulty path of length at most d(s,t) + O(k2) in O(F + m) time for any two nonfaulty nodes s and t in the k-safe DC(m) with number of faulty nodes F < 2k(m + 1 - k), where 0≤ k ≤ m/2. The second algorithm is an online algorithm that uses local information only. It can find a fault-free path with high probability in an arbitrarily faulty dual-cube with unbounded number of faulty nodes. [ABSTRACT FROM AUTHOR]

Interruptible load management (ILM) is an important part of Demand Side Management (DSM), especially in power market. It has deep influences on reliability and economical operation of power system. How to use a rational model to simulate the ILM becomes a hot topic in China. This paper gives the optimal purchase model of interruptible contract and sets a reasonable selected rule, i.e. the interruptible load should be priorly scheduled in the period with maximal shortage capacity. Based on the rule, the heuristic method is employed to solve the problem. Simulation results of real power system demonstrate the usefulness of the proposed model. [ABSTRACT FROM AUTHOR]

Web user patterns can be used to create a more robust web information service in personalization. But the user interests are changeable, that is, they differ from one user to another, and they are constantly changing for a specific user. This paper presents a dynamic mining approach based on Markov model to solve this problem. Markov model is introduced to keep track of the changes of user interest according to his or her navigational behaviors. Some new concepts in the model are defined. An algorithm based on the model is then designed to learn the user's favorite navigation paths. The approach is implemented in an example website, and the experimental results proved the effective of our approach. [ABSTRACT FROM AUTHOR]

With the rapidly increasing competitiveness in global market, dynamic alliances and virtual enterprises are becoming essential components of the economy in order to meet the market requirements for quality, responsiveness, and customer satisfaction. Partner selection is a key stage in the formation of a successful virtual enterprise. The process can be considered as a multi-class classification problem. In this paper, The Support Vector Machine (SVM) technique is proposed to perform automated ranking of potential partners. Experimental results indicate that desirable outcome can be obtained by using the SVM method in partner selections. In comparison with other methods in the literatures, the SVM-based method is advantageous in terms of generalization performance and the fitness accuracy with a limited number of training datasets. [ABSTRACT FROM AUTHOR]

Motion estimation is an important part of video encoding systems, because it can significantly affect the output quality and the compression ratio. Motion estimation which consists of integer pixel motion estimation and half pixel motion estimation is very computationally intensive part. To reduce the computational complexity, many methods have been proposed in both integer pixel motion estimation and half pixel motion estimation. For integer pixel motion estimation, some fast methods could reduce their computational complexity significantly. There remains, however, room for improvement in the performance of current methods for half pixel motion estimation. In this paper, an efficient half pixel motion estimation algorithm based on spatial correlations is proposed to reduce the computational complexity. According to spatially correlated information, the proposed method decides whether half pixel motion estimation is performed or not for the current block. Experimental results show that the proposed method outperforms most of current methods in computation complexity by reducing the number of search points with little degradation in image quality. When compared to full half pixel search method, the proposed algorithm achieves the search point reduction up to 96% with only 0.01 ~ 0.1 (dB) degradation of image quality. [ABSTRACT FROM AUTHOR]

A Chaikin curve is a subdivision curve. Subdivision begins from an initial control polygonal curve. For each subdivision step, all corners of the polygonal curve are cut off, and a new polygonal curve is thus produced as the input of the next subdivision step. In the limit of subdivision, a Chaikin curve is created. In this paper, a multi-step subdivision algorithm for generating Chaikin curves is proposed. For an arbitrary positive integer k, the algorithm builds the resultant polygonal curve of the kth subdivision step directly from the initial polygonal curve. Examples show that the new algorithm speeds up curve generation in several times. Keywords: Subdivision scheme; Chaikin curve; Corner cutting. [ABSTRACT FROM AUTHOR]

To estimate an accuracy motion vector (MV), a two step search is generally used. In the first step, integer pixel points within a search area are examined to find the integer pixel MV. Then, in the second step, 8 half pixel points around the selected integer pixel MV are examined and the best matching point is chosen as the final MV. Many fast integer pixel motion estimation (ME) algorithms can be found by examining less than about 10 search points. However, the half pixel ME requires huge computational complexity. In this paper, We propose a new fast algorithm for half pixel ME that reduces the computational overhead by limiting the number of interpolations of the candidate half pixel points. The proposed method based on the property of MVs and the correlations between integer pixel MVs and half pixel MVs. Experimental results show that the speedup improvement of the proposed algorithm over a full half pixel search (FHPS), horizontal and vertical directions as references (HVDR), chen's half pixel search algorithm (CHPS-1) and a parabolic prediction-based fast half-pixel search (PPHPS) can be up to 1.4 ~ 3.9 times on average. Also the image quality improvement can be better up to 0.05(dB) ~ 0.1(dB) compare with CHPS and PPHPS. [ABSTRACT FROM AUTHOR]

In order to extract the region of an object from an image, the difference image method is attractive since it is computationally inexpensive. However, the difference image is not frequently used due to the noise in the difference image. In this paper, we analyze the noise in an uncalibrated difference image and propose a statistical noise calibration method. In the experiment, the proposed method is verified using a real image. [ABSTRACT FROM AUTHOR]

This paper proposes a method for tracking and identifying persons from video image frames taken by a fixed camera. The majority of conventional video tracking surveillance systems assumes a likeness to a person's appearance for some time, and existing human tracking systems usually consider short-term situations. To address this situation, we use an adaptive background and human body model updated statistically frame-by-frame to correctly construct a person with body parts. The formed person is labeled and recorded in a person's list, which stores the individual's human body model details. Such recorded information can be used to identify tracked persons. The results of this experiment are demonstrated in several indoor situations. [ABSTRACT FROM AUTHOR]

Up to face extrusion (UTFE) is an effective operation to extrude the profile from a sketch plane to a selected face. An up to face extrusion algorithm is presented in this paper. The algorithm first generates the trimmed extrusion through a simple body-surface Boolean operation method, and then generates the resultant solid through a regularized Boolean operation between the original solid and the trimmed extrusion. The algorithm has been implemented in a commercial geometric modeling software system TiGems. Examples are given to illustrate the algorithm. [ABSTRACT FROM AUTHOR]