• Journal of the Korean Society for information Management
• /
• v.15 no.1
• /
• pp.83-108
• /
• 1998

Recently, information on international trade goes on increasing in quantity because of the globalism and many related areas of the field. Most of libraries and informatin centers in Korea are using Dewey Decimal Classification(DDC), Library of congress Classification(LCC), and Korean Decimal Classification(KDC) to classify library materials on the subject. The application of three classification shcemes, DDC, LCC, and KDC were queried to determine the classification of materials on international trade. And analyses of the parts of international trade in three classification shemes were done in order to identify what major changes have made with the development of the field. There was subject scatter in DDC and LCC; there was an overlap among the classes of the three systems; and there was little change between present editions and the previous editions. The revision for international trade field of the KDC, the 4t edtition was suggested to help cover some deficiencies of the classification scheme. Inorder to develop a better KDC, the 5th edition, continuous revisions based upon the opinions of subject specialists and catalogers in the field are highly recommended.

• Journal of Korean Library and Information Science Society
• /
• v.39 no.3
• /
• pp.345-368
• /
• 2008

This study investigated the general problems concerning the subject Computer Science in the KDC(Korean Decimal Classification) 4th edition based on the comparative analysis with DDC, NDC, Disciplinary Classification System of Korean Research Foundation and National Standard Science and Technology Classification and Science and Technology Classification of Korea Science and Engineering Foundation, and suggested some ideas for the improvements of them. The subject of Computer science in the KDC 4th edition will be helpful to be improved to integrate in classes 004-005 now separated into two main classes of 000(004-005) and 500(566) in KDC4, to systematize subdivisions, to add new subjects, to delete and relocate some inappropriate subjects and to add notes.

• Proceedings of the Korean Statistical Society Conference
• /
• 2004.11a
• /
• pp.29-34
• /
• 2004

계속 반복하여 실시되는 통계조사에서 조사원은 오차를 발생시키는 주요 요인으로 간주되고 있다 조사원에 의한 오차를 측정하는 방법으로서 조사표 형태별로 조사원, 집락 및 가구 등 변수에 따라 할당하고 선계방법에 따른 추정 값에 대한 효과 및 효과의 분산을 산출하는 모델을 제시한다. 또한 실제 조사모델로부터 품질관리표본을 추출하여 이를 대상으로 리인터뷰를 실시한 결과를 조사원의 인구통계학적 특성별로 분석하고 불일치지수 등을 산출함으로써 오차를 분석하는 방법을 제시한다.

• The Korean Journal of Applied Statistics
• /
• v.17 no.3
• /
• pp.499-505
• /
• 2004

The Pareto diagram analysis of the experimental data by the two level orthogonal arrays has been used widely in practice since it is a graphical, quick and easy method to analyze experimental results, which does not use the analysis of variance to screen significant effects. For the analysis of the experimental data by $L_{18}(2 \times 3^7)$ orthogonal array, Park(1996) proposed Pareto ANOVA in which the size of effects is defined by the mean squares of effects and the Pareto principle is used. In this paper, a new approach of the Pareto diagram analysis of the experimental data by $L_{18}(2 \times 3^7)$ orthogonal array is proposed. The main idea is to partition the size of three level effects by that of linear and quadratic orthogonal contrasts of those effects.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.10a
• /
• pp.162-165
• /
• 2004

On this study, we improved diaphgram for micro speaker performance using Taguchi method in discrete design space. The design of diaphgram has an effect on performance of micro speaker such as, thickness of diaphgram, shape of diaphgram, etc. Therefore this study carried to decide shape of diaphgram and thickness of diaphgram for minimizing 2nd natural frequency of diaphgram using Taguchi method. we showed improved design factors that minimized 2nd natural frequency of diaphgram. Also, 2nd natural frequency of diaphgram for micro speaker is reduced up to 37 percent maintaining twist mode shape. From the results of ANOVA, 2nd natural frequency of diaphgram for micro speaker have an effect on position of the outer curved shape and thickness of diaphgram.

• Journal of Korean Society of Forest Science
• /
• v.26 no.1
• /
• pp.13-18
• /
• 1975

This study was intended to clarify interrelations among seven characters of bamboo and their influences upon its culm-volume. The analysis of covariance was used to obtain phenotypic correlations, genotypic correlations and environmental correlations among some characters of Phyllostachys bambusoides Sieb. et Zucc., and thereby path-coefficients were calculated based on Dewey's method. The characters considered here included the breast height diameter, culm-height, clear-length, subterranean stem, number of bamboo joints, butt-end diameter and culm-volume of bamboo. Average values, standard errors, variances and standard deviations for the characters mentioned above are shown in Table 1, and phenotypic correlations, genotypic correlations and environmental correlations among seven characters are shown in Table 2, according to the results, there are highly significant relationships among lines but not among some replications. According to Table 4, heritability values in the breast height and butt-end diameters are higher than those in other characters mentioned above. On the other hand, environmental correlations among general characters appear to have lower values than phenotypic and genotypic correlations do. It also appears that the butt-end diameter and breast height diameter are highly correlated with the culm-volume of bamboo. The path-coefficients of individual characters to the culm-volume of bamboo are computed from the correlations (Table 4) and presented in Figure 1 and Table 5, where it could shown the direct and indirect effects on the bamboo culm-volume of each character.

• The Korean Journal of Financial Management
• /
• v.17 no.1
• /
• pp.161-180
• /
• 2000

본 연구는 주가를 예측하는데 있어서 선형 회귀모형을 이용하는 방법과 비선형 인공신경망 모형을 이용하는 방법을 비교 분석하여, 어떤 모형이 더 우수한 예측성과를 내는지를 검증한다. 자본시장에서 투자자들은 접근하는 정보가 다르고 각기 상이한 예측 변수들을 토대로 나름대로의 예측치를 만들어 낸다. 이렇게 볼 때 개별 투자자들이 이용하는 다양한 정보집합을 결합하여 단일의 뛰어난 정보집합을 만들어내는 것은 매우 어려운 과제이다. 따라서 본 연구에서는 이용 가능한 소수의 예측 변수들을 어떤 방식으로 결합하는 것이 예측오차의 분산을 최소화할 수 있는지에 대한 현실적인 접근방법을 모색하고자 한다. 거시경제변수나 시장자료를 입력변수로 사용한 기존 연구와는 달리 본 연구에서는 재무제표 정보를 입력변수로 사용하였다 즉, 대차대조표의 최종요약치인 주당 지분의 장부가치와 손익계산서의 최종요약치인 주당 순이익을 입력변수로 사용했으며 1991년부터 1995년까지의 추정(학습)결과를 토대로 모형을 선택하여 1996년의 제무제표 정보로 1997년의 주가를 예측하는 것이 본 연구의 과제이다. 연구결과, 대체로 선형회귀모형에 비해 비선형 신경망 모형이 예측오차의 분산을 감소시키는 것으로 나타났다.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2015.10a
• /
• pp.1316-1319
• /
• 2015

본 논문에서는 대규모 분산 병렬 컴퓨팅 환경인 하둡 클러스터 시스템을 이용하여, 공간 객체들 간의 위상 관계를 효율적으로 추론하는 대용량 정성 공간 추론기를 제안한다. 본 논문에서 제안하는 공간 추론기는 추론 작업의 순차성과 반복성을 고려하여, 작업들 간의 디스크 입출력을 최소화할 수 있는 인-메모리 기반의 아파치 스파크 프레임워크를 이용하여 개발하였다. 따라서 본 추론기에서는 추론의 대상이 되는 대용량 공간 지식들을 아파치 스파크의 분산 데이터 집합 형태인 PairRDD와 RDD로 변환하고, 이들에 대한 데이터 오퍼레이션들로 추론 작업들을 구현하였다. 또한, 본 추론기에서는 추론 시간의 많은 부분을 차지하는 이행 관계 추론에 필요한 조합표를 효과적으로 축소함으로써, 공간 추론 작업의 성능을 크게 향상시켰다. 대용량의 공간 지식 베이스를 이용한 성능 분석 실험을 통해, 본 논문에서 제안한 정성 공간 추론기의 높은 성능을 확인할 수 있었다.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.20 no.6
• /
• pp.557-564
• /
• 2019

The characteristics of the torque and torque ripple of Interior Permanent Magnet Synchronous Motor(IPMSM) are influenced by the size and position of the rotor magnet and the size of the stator slot. This paper deals with the optimal design method for improving torque and torque ripplerate for IPMSM using Response Surface Methodology(RSM). Two objective functions of torque output and torque ripple were derived from the sensitivity analysis by Plackett-Burmann(PB) for the characteristic variables affecting torque and torque ripple. Secondary characteristic variables were selected from the derived objective function and RSM secondary regression model function was estimated by the experiment schedule and analysis results according to the Central Composite Design (CCD). The reliability of the secondary regression model was verified using ANOVA table. The analysis according to the experimental schedule was verified by JMAG(Ver. 18.0) which is Finite Element Method(FEM) software. The torque output of IPMSM applied with final characteristic variables was increased torque output by 11.5 % and the torque ripplerate was reduced by 9.1 %.

• The Korean Journal of Applied Statistics
• /
• v.26 no.4
• /
• pp.675-686
• /
• 2013

The Korea Food and Drug Administration(KFDA) recommends the use of a $2{\times}2$ crossover design to assess the bioequivalence of generic drugs. However, a standard $2{\times}2$ crossover design for bioequivalence trials is often considered problematic due to ethical and economic issues as highly variable drugs are usually required by large numbers of subjects when designing the trial. To overcome this problem a $2{\times}4$ crossover design has been a recommended option as per US regulations; in addition, a $2{\times}3$ crossover design has also recently drawn special attention as an efficient alternative. The current KFDA regulation requires an ANOVA table for every bioequivalence study; however, ANOVA tables of $2{\times}4$ and $2{\times}3$ crossover designs have never been published in the literature. This study shows the derivation of tables of analysis of variance for a $2{\times}4$ cross-over design and a $2{\times}3$ cross-over design. We also suggest a sample size formulas for $2{\times}2$, $2{\times}4$ and $2{\times}3$ crossover designs to provide information on the selection of efficient designs for highly variable drugs.