• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.16 no.12
• /
• pp.1249-1265
• /
• 1991

In this paper, a fast and adaptive feature extraction algorithm for textured image segmentation is proposed. First, a conventional algorithm to extract the statistical texture features are described and we obtain the recursive equations from that conventional method and it is used for extraction of sevaral texture features. And also we propose the adaptive algorithm which extract the texture features. To evaluate the performance of proposed algorithm, we apply the proposed method to artificial texture images. From the results of computer simulation, the proposed method is superior to the conventional one.

• Tuberculosis and Respiratory Diseases
• /
• v.57 no.2
• /
• pp.168-179
• /
• 2004

Background : The statistical analysis is an essential procedure ensuring that the results of researches are based on evidences rather than opinion. The purpose of this study is to evaluate which statistical techniques are used and whether these statistical methods are used appropriately or not in the journal of Tuberculosis and Respiratory Diseases. Materials and Methods : We reviewed 185 articles reported in the journal of Tuberculosis and Respiratory Diseases in 1999. We evaluated the validity of used statistical methods based upon the checklist that was developed on the basis of the guideline for statistical reporting in articles for medical journals by International Committee of Medical Journal Editors. Results : Among 185 articles, original articles and case reports were 110 (59.5%) and 61 (33.0%) respectively. In 112 articles excluding case reports and reviews, statistical techniques were used in 107 articles (95.5%). In 94 articles (83.9%) descriptive and inferential methods were used, while in 13 (11.6%) articles only descriptive methods were used. With the types of inferential statistical techniques, comparison of means was most commonly used (64/94, 68.1%), followed by contingency table (43/94, 45.7%) and correlation or regression (18/94, 19.1%). Among the articles in which descriptive methods were used, 83.2% (89/107) showed inappropriate central tendency and dispersion. In the articles in which inferential methods were used, improper methods were applied in 88.8% (79/89) and the most frequent misuse of statistical methods was inappropriate use of parametric methods (35/89, 39.3%). Only 14 articles (13.1%) were satisfactory in utilization of statistical methodology. Conclusion : Most of the statistical errors found in the journal were misuses of statistical methods related to basic statistics. This study suggests that researchers should be more careful when they describe and apply statistical methods and more extensive statistical refereeing system would be needed.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2005.05a
• /
• pp.1068-1071
• /
• 2005

최근 들어 기술을 담보로 하는 신용금융의 역할이 증대되면서 자금지원 대상기업의 기술평가 시스템 구축이 중요한 과제가 되고 있다. 국내에서는 기업 보유의 기술경영성과를 측정하여 한정된 자원의 효율적 배분을 위한 민간 투, 융자를 위한 기술신용평가모형'이 제시되었다 본 연구에서는 기술신용평가모델의 평가항목 타당성을 실증 분석한다. 모형의 항목 분류가 적절하게 되었는지를 검증하기 위하여 구조적 타당성을 평가하며 통계적 유의성을 검증하여 신뢰성을 평가한다. 구조적 타당성 검정을 위해 확인 요인분석을 수행하며 평가모형의 신뢰성을 검증하기 위해서는 다변량 통계방법 중의 하나인 판별분석을 수행한다. 본 연구는 기술개발 성공 및 부실발생의 예측력을 갖는 기술신용평가 시스템 구축을 위한 기초 자료로 활용될 수 있을 것이다.

• Annual Conference on Human and Language Technology
• /
• 2009.10a
• /
• pp.225-230
• /
• 2009

본 논문에서는 중국어의 이메일 특성을 이용한 중한 대화체 자동번역 방법에 대하여 기술한다. 본 논문에서는 중국어와 한국어와 같이 언어 간의 어순이 다르고 이메일과 같이 특정한 도메인의 언어적 자원도 제한적인 특성을 고려하여 중국어 이메일 특성을 이용한 규칙 기반의 번역 방법을 시도하였다. 이를 위해, 본 논문에서는 중국어의 굳어진 표현이 많고, 한글자 단어 많으며, 입력 오류 많고, 청유 및 경어가 많은 이메일 특성 분석을 통해 그에 대응되는 처리 방법을 제안하였다. 그리고, 그 방법의 타당성을 증명하기 위해 규칙기반의 중한 뉴스 자동번역 시스템과 비교 실험을 하였으며, 규칙기반과 통계적 방법의 타당성 실험을 위해 Gmail과도 비교 실험을 하였다. 두 가지 비교 실험 결과, 본 논문에서 접근한 방법이 모두 우수하였으며, 그 타당성을 증명하였다.

• Journal of Advanced Navigation Technology
• /
• v.11 no.1
• /
• pp.105-111
• /
• 2007

This paper is concerned with fuzzy inference-based optimal sub-bands decision scheme which is to be embedded the watermark. It concentrated not only on design of fuzzy inference algorithm but also on human visual parameters (HVP), such as contrast sensitivity, texture degree. In the first, such human visual parameters as contrast sensitivity, texture degree as well as statistical characteristics are involved to select the optimal coefficients region. Secondly, fuzzy if - then rule which can be able to adapt the wide variety of environments is developed. The performance of proposed approach is evaluated with respect to the imperceptibility and correctness of watermark. According to some experimental results, contrast sensitivity function is superior in smooth image. On the other hand, statistical characteristics provide good results in rough images.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.4
• /
• pp.2401-2406
• /
• 2015

Pipelines are used by large heavy industries to deliver various types of fluids. Since this is important to maintain the performance of large systems, it is necessary to accurately predict remaining life of the corroded pipeline. However, predicting the remaining life is difficult due to uncertainties in the associated variables, such as geometries, material properties, corrosion rate, etc. In this paper, a statistical method for predicting corrosion remaining life is proposed using Bayesian inference. To accomplish this, pipeline failure probability was calculated using prior information about pipeline failure pressure according to elapsed time, and the given experimental data based on Bayes' rule. The corrosion remaining life was calculated as the elapsed time with 10 % failure probability. Using 10 and 50 samples generated from random variables affecting the corrosion of the pipe, the pipeline failure probability was estimated, after which the estimated remaining useful life was compared with the assumed true remaining useful life.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2023.05a
• /
• pp.508-508
• /
• 2023

하천의 수질 측정은 환경 보호, 공공 안전, 생태계 건강 및 기후 변화 대응과 같은 중요한 측면에서 필수적이다. 특히, 유량과 수질 간의 관계를 이해하는 것은 효과적인 하천 관리와 보전에 결정적인 역할을 한다. 본 연구는 총량측정망 중 한국수자원조사기술원에서 유량자료를 제공하는 측정 지점을 대상으로 수질 측정 항목과 유량 측정값을 활용하여 하천 상태를 분석하고자 한다. 이를 통해 수질과 유량 간의 관계를 파악하고, 하천 관리와 보전을 위한 기초자료로 활용되고자 한다. 분석에 사용된 수질 항목은 수온, pH, 전기전도도, 용존산소, BOD, COD, 총질소, 총인 등이며, 통계적 분석 방법으로는 상관분석, 회귀분석, 주성분분석 등이 사용되었다. 분석결과 유량이 높은 지점에서 일부 수질 항목의 오염도가 낮아진 경향이 발견되었으며, 특정 수질 항목 간에는 상관관계가 나타났다. 본 연구의 결과를 바탕으로 하천의 수질 개선과 관리 전략을 수립하는데 기여할 수 있을 것으로 기대된다.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.30 no.1
• /
• pp.20-30
• /
• 2010

In this paper, a new tomographic scan method with fixed installed detectors and rotating source from gamma projector was presented to diagnose the industrial plants which were impossible to be examined by conventional tomographic systems. Weight matrix calculation method which was suitable for volumetric detector and statistical iterative reconstruction method were applied for reconstructing the simulation and experimental data. Monte Carlo simulations had been performed for two kinds of phantoms. Lab scale experiment with a same condition as one of phantoms, had been carried out. Simulation results showed that reconstruction from photopeak counting measurement gave the better results than from the gross counting measurement although photopeak counting measurement had large statistical errors. Experimental data showed the similar result as Monte Carlo simulation. Those results appeared to be promising for industrial tomographic applications, especially for petrochemical industries.

• Journal of the Korea Computer Graphics Society
• /
• v.29 no.1
• /
• pp.13-22
• /
• 2023

In this paper, we present a method for estimating full 3D shapes from given 2D silhouette images of human bodies. Because the silhouette only consists of the partial information on the true shape, it is an ill-posed problem. To address the problem, we use the statistical human shape space obtained from the existing large 3D human shape database. The method consists of three steps. First, we extract the boundary pixels and their appropriate normal vectors from the input silhouette images. Then, we initialize the correspondences of each pixel to the vertex of the statistically-deformable 3D human model. Finally, we numerically optimize the parameters of the statistical model to fit best to the given silhouettes. The viability and the robustness of the method is demonstrated with various experiments.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.7 no.2
• /
• pp.101-106
• /
• 2006

The optimum design of turbine blade at minimized fatigue life can be derived by the statistical fatigue analysis in this study, The optimum value of positions in the axes of X and Y at turbine blade can be found by design of experiments on the condition that the value of fillet radius is fixed to minimize the fatigue life. The degree of uncertainty about process at the factors in the axes of X and Y can be calculated by six sigma analysis. The optimum value of fillet radius is determined by utilizing the robust design at uncertain condition. It is concluded that maximum von Mises stress can decreased by 20% and the fatigue life can be double.