• Communications for Statistical Applications and Methods
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• v.8 no.3
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• pp.643-650
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• 2001

Some classical plots like scatterplot matrices and parallel coordinates are valuable tools for data visualization. These tools are extensively used in the modern data mining softwares to explore the inherent data structure, and hence to visually classify or cluster the database into appropriate groups. However, the interpretation of these plots are very sensitive to the arrangement of variables. In this work, we introduce two methods to arrange the variables for data visualization. First method is based on the work of Wegman (1999), and this is to arrange the variables using minimum distance among all the pairwise permutation of the variables. Second method is using the idea of principal components. We Investigate the effectiveness of these methods with parallel coordinates using real data sets, and show that each of the two proposed methods has its own strength from different aspects respectively.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1991.10a
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• pp.6-22
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• 1991

This thesis presents a parallel implementation of an iterative method for large scale, sparse linear system and gives result of computational experiments performed on both single transputer and multi transputer parallel computers. To solve linear system, we use conjugate gradient method and develope data storage techinique, data communication scheme. In addition to the explanation of conjugate gradient method, the result of computational experiment is summarized.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.11A
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• pp.1963-1970
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• 2001

It is essential design process to analyze processing method and set out top level HW configuration using main parameters before implementation of the SAR processor. This paper identifies the impact of the I/O and algorithm structure upon the parallel processing to be assessed and suggests the practical mapping method fur parallel processing to the SAR data. Also, simulation is performed to the E-SAR processor to examine the usefulness of the method, and the results are analyzed and discussed.

• The Transactions of the Korea Information Processing Society
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• v.6 no.5
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• pp.1219-1224
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• 1999

This paper derived Montgomery's parallel algorithms for modular multiplication based on Walter's and Iwamura's method, and compared data dependence graph of each parallel algorithm. Comparing the result, Walter's parallel algorithm has small computational index in data dependence graph, so it is selected and used to computed spatial and temporal pipelining diagrams with each projection direction for designing expansible bit-level systolic array. We also evaluated internal operation of proposed expansible systolic array C++ language.

• The Transactions of the Korean Institute of Power Electronics
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• v.14 no.4
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• pp.278-284
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• 2009

This paper presents a firing angle controller of a thyristor converter for DC power supply using PID controller with parallel data loop to improve the dynamic response. The proposed parallel data loop for firing angle controller of 3-phase semi-converter, generates pre-measured firing angle according to reference voltage and load current. With the approximated firing angle according to operating conditions, the output voltage can fast keep the reference value with small voltage error. And the PID controller compensates the output voltage error from the firing angle of parallel data loop. In order to reduce the sudden changing of the data from current ripple, a simple digital low pass filter is used to determine the output data. The proposed control scheme is verified by the experimental test of a practical 50[A] grade thyristor converter system.

• Journal of Convergence for Information Technology
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• v.8 no.6
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• pp.237-242
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• 2018

There are various 'wireless communication technologies' around us. Wireless mobile communication has evolved through various stages, and its utilization is also diverse. However, due to the development of wireless communication technology, the demand for frequency resources is much higher than the supply, so frequency shortage is serious. Recently, 'visible light communication' has been attracting attention as an emerging communication technology that can solve the frequency shortage. 'Visible light communication' is a communication method based on serial data transmission / reception, and there is a difficulty in transmitting / receiving parallel data because the transmitter and the receiver are arbitrarily present. In this paper, we have studied parallel data processing of visible light communication. We could solve the problem by analyzing parallel data using image processing. Through this study, communication performance can be verified through I / O data comparison by implementing parallel data analysis method. It is expected that diversity in parallel data analysis will be presented through the results.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.1
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• pp.13-19
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• 2019

The accuracy of machine learning is greatly affected by amount of learning data and quality of data. Collecting existing Web-based learning data has danger that data unrelated to actual learning can be collected, and it is impossible to secure data transparency. In this paper, we propose a method for collecting data directly in parallel by blocks in a block - chain structure, and comparing the data collected by each block with data in other blocks to select only good data. In the proposed system, each block shares data with each other through a chain of blocks, utilizes the All-reduce structure of Parallel-SGD to select only good quality data through comparison with other block data to construct a learning data set. Also, in order to verify the performance of the proposed architecture, we verify that the original image is only good data among the modulated images using the existing benchmark data set.

• Journal of Internet Computing and Services
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• v.7 no.1
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• pp.131-141
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• 2006

Recently, many researchers have been studied several high performance data transmission techniques such as TCP buffer Tuning, XCP and Parallel Sockets. The Parallel Sockets is an application level library for parallel data transfer, while TCP tuning, XCP and DRS are developed on kernel level. However, parallel socket is not analyzed in detail yet and need more enhancements, In this paper, we verify performance of parallel transfer technique through several experiments and analyze character of traffic interference among socket connections. In order to enhance parallel transfer management mechanism, we predict the number of socket connections to obtain SLA of the network resource and at the same time, affected network bandwidth of existing connections is measured mathematically due to the interference of other parallel transmission. Our analytical scheme predicts very well network bandwidth for applications using the parallel socket only with 8% error.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.2 no.2
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• pp.133-138
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• 2002

In this paper, we propose an integrated GUI environment of parallel fuzzy inference system fur pattern classification of remote sensing data. In this, as 4 fuzzy variables in condition part and 104 fuzzy rules are used, a real time and parallel approach is required. For frost fuzzy computation, we use the scan line conversion algorithm to convert lines of each fuzzy linguistic term to the closest integer pixels. We design 4 fuzzy processor unit to be operated in parallel by using FPGA. As a GUI environment, PCI transmission, image data pre-processing, integer pixel mapping and fuzzy membership tuning are considered. This system can be used in a pattern classification system requiring a rapid inference time in a real-time.

• Journal of KIISE:Computer Systems and Theory
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• v.30 no.3_4
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• pp.117-129
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• 2003

In this paper, we propose advanced parallel join algorithm to efficiently process join operation on hypercube systems. This algorithm uses a broadcasting method in processing relation R which is compatible with hypercube structure. Hence, we can present optimized parallel join algorithm for that hypercube structure. The proposed algorithm has a complete solution of two essential problems - load balancing problem and data skew problem - in parallelization of join operation. In order to solve these problems, we made good use of the characteristics of clustering effect in the algorithm. As a result of this, performance is improved on the whole system than existing algorithms. Moreover. new algorithm has an advantage that can implement non-equijoin operation easily which is difficult to be implemented in hash based algorithm. Finally, according to the cost model analysis. this algorithm showed better performance than existing parallel join algorithms.