• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.27 no.7
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• pp.76-81
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• 2013

This paper presents an effective pedagogical method for nodal analysis in linear circuit. In the proposed method, basic equations are built only for passive elements and independent current sources. And then, the basic equations are modified by considering other sources such as voltage sources and dependent current sources. In the proposed method, the equations are presented in form of a matrix and a vector of which elements are built systematically by considering every element in a circuit one by one. This make the proposed method easy to apply to intricately composed circuit and easy to solve the final simultaneous equations and easy to realize as computer program for nodal analysis and easy to memorize compared to the conventional method.

• Journal of the Korean School Mathematics Society
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• v.3 no.2
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• pp.59-67
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• 2000

Two groups of students, who are the students in the natural science course of high school in Korea, learned the equation of figure in space (point, line, plane) to understand more effectively with two different textbooks. One group was taught with the textbook used now in most high schools and the other group was taught with the textbooks systematized by associating old concept with new concept. The results are as follows : 1) We need understand the basic concept of vector plainly and flexibly to apply it to the solution of problems. 2) It helps students understand new concepts how we should establish the concept about point, line and plane in space by applying the concept about those on XY plane, 3) It is very effective in understanding the new knowledge system more easily to analyze the existent concepts and to arrange them systematically for efficient understanding of new concepts. 4) The texts which consist of contents organized by basic concepts improve students' learning ability.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.2
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• pp.44-58
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• 2014

In this study, a standard vector data model was developed for interoperability of river-geospatial information and for verification purpose the applicability of the standard vector model was evaluated using a model to RIMGIS vector data at Changnyeong-Hapcheon & Gangjung-Goryeong irrigation watershed. The standards from ISO and OGC were analyzed and the river geospatial data model standard was established by applying the standards. The ERD was designed based on the analysis information on data characteristics and relationship. The verification of RIMGIS vector data included points, lines and polygon to develope GDM was carried out by comparing with the data by layer. This conducting comparison of basic spatial data and attribute data to each record and spatial information vertex. The error in the process of conversion was 0 %, indicating no problem with model. Our Geospatial Data Model presented in this study provides a new and consistent format for the storage and retrieval of river geospatial data from connected database. It is designed to facilitators integrated analysis of large data sets collected by multiple institutes.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.3
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• pp.628-636
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• 2010

In this paper, we present a new type high speed parallel multiplier for performing the multiplication of two polynomials using standard basis in the finite fields GF($2^m$). Prior to construct the multiplier circuits, we design the basic cell of vector code generator(VCG) to perform the parallel multiplication of a multiplicand polynomial with a irreducible polynomial and design the partial product result cell(PPC) to generate the result of bit-parallel multiplication with one coefficient of a multiplicative polynomial with VCG circuits. The presented multiplier performs high speed parallel multiplication to connect PPC with VCG. The basic cell of VCG and PPC consists of one AND gate and one XOR gate respectively. Extending this process, we show the design of the generalized circuits for degree m and a simple example of constructing the multiplier circuit over finite fields GF($2^4$). Also, the presented multiplier is simulated by PSpice. The multiplier presented in this paper uses the VCGs and PPCS repeatedly, and is easy to extend the multiplication of two polynomials in the finite fields with very large degree m, and is suitable to VLSL.

• Journal of Internet Computing and Services
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• v.12 no.6
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• pp.63-71
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• 2011

Cardiac disorder data are generally tested using the classifier and QRS-Complex and R-R interval which is used in this experiment are often extracted by ECG(Electrocardiogram) signals. The experimentation of ECG data with classifier is generally performed with SVM(Support Vector Machine) and MLP(Multilayer Perceptron) classifier, but this study experimented with Best-First Decision Tree(B-F Tree) derived from the Dicision Tree among Random Forest classifier algorithms to improve accuracy. To compare and analyze accuracy, experimentation of SVM, MLP, RBF(Radial Basic Function) Network and Decision Tree classifiers are performed and also compared the result of announced papers carried out under same interval and data. Comparing the accuracy of Random Forest classifier with above four ones, Random Forest is the best in accuracy. As though R-R interval was extracted using Band-pass filter in pre-processing of this experiment, in future, more filter study is needed to extract accurate interval.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.6
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• pp.673-679
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• 2014

The important requirements of designing a pattern classifier are high throughput and low memory requirements, and low cost hardware implementation. A pattern classifier by using Multiple Attractor Cellular Automata(MACA) proposed by Maji et al. reduced the complexity of the classification algorithm from $O(n^3)$ to O(n) by using Dependency Vector(DV) and Dependency String(DS). In this paper, we generate a pattern classifier using LFSR to improve efficiently the space and time complexity and we propose a method for finding DV by using the 0-basic path. Also we investigate DV and the attractor of the generated pattern classifier. We can divide an n-bit DS by m number of $DV_i$ s and generate various pattern classifiers.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.1
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• pp.1-5
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• 2009

This paper suggests to apply mirror-reflected method based 2D emotion recognition database to 3D application. Also, it makes facial expression of fuzzy modeling using probability of emotion. Suggested facial expression function applies fuzzy theory to 3 basic movement for facial expressions. This method applies 3D application to feature vector for emotion recognition from 2D application using mirror-reflected multi-image. Thus, we can have model based on fuzzy nonlinear facial expression of a 2D model for a real model. We use average values about probability of 6 basic expressions such as happy, sad, disgust, angry, surprise and fear. Furthermore, dynimic facial expressions are made via fuzzy modelling. This paper compares and analyzes feature vectors of real model with 3D human-like avatar.

• Transactions of the Society of Information Storage Systems
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• v.8 no.2
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• pp.39-43
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• 2012

In spite of many advantages, the practical application of the thin film solar cell is restricted due to its low efficiency compared with the bulk type solar cells. This study intends to adopt the surface plasmon effect using nano particles to solve the low efficiency problem in thin film solar cells. By inserting Ag nano-particles in the absorbing layer of a thin film solar cell, the poynting vector value of the absorbing layer is increased due to the strong energy field. Increasing the value may give thin film solar cells chance to absorb more energy from the incident beam so that the efficiency of the thin film solar cell can be improved. In this work, we have designed the optimal shape of Ag nano-particle in the absorbing laser of a basic type thin film solar cell using the finite element analysis commercial package COMSOL. Design parameters are set to the particle diameter and the distance between each Ag nano-particle and by changing those parameters using the full factorial design variable set-up, we can determine optimal design of Ag nano-particles for maximizing the poynting vector value in the absorbing layer.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.6
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• pp.1170-1177
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• 1997

Morphology is a shape preseving filter. Several morphology filter can be made by the combination of morphological basic operation. If we use morphology filter in decimation process for a hierarchical encoder, there are some advantagesin reduction aliasing effects. In this paper, we propose a new hierarchical coder with morphological filtering and vector quantization. And then, firstly, we confirm that CO filtering is the best one among the 4 kinds of morphology filters to reduce aliasing effects in Laplacian pyramid transmission proposed by Burt. Secondly, the those two coders was compared. The results of our simulation show that our new coder surpasser the Laplacian pyramid especially in complex images.

• Journal of Electrical Engineering and Technology
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• v.10 no.2
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• pp.574-585
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• 2015

This paper aims to improve the performance of conventional direct torque control (DTC) drives proposed by Takahashi by extending the idea for 5-level inverter. Hybrid cascaded H-bridge topology is used to achieve inverter voltage vector composed of 5-level of voltage. Although DTC is very popular for its simplicity but it suffers from some disadvantages like- high torque ripple and uncontrollable switching frequency. To compensate these shortcomings conventional DTC strategy is modified for five levels voltage source inverter (VSI). Multilevel hysteresis controller for both flux and torque is used. Optimal voltage vector selection from precise lookup table utilizing 12 sector, 9 torque level and 4 flux level is proposed to improve DTC performance. These voltage references are produced utilizing a hybrid cascaded H-bridge multilevel inverter, where inverter each phase can be realized using multiple dc source. Fuel cells, car batteries or ultra-capacitor are normally the choice of required dc source. Simulation results shows that the DTC drive performance is considerably improved in terms of lower torque and flux ripple and less THD. These have been experimentally evaluated and compared with the basic DTC developed by Takahashi.