• International Journal of Advanced Culture Technology
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• 제1권2호
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• pp.13-17
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• 2013

Today, most of the companies have numerous issues to take advantage of the data within the organization. Modeling techniques could be described using profile and historical log data as a tool of data mining techniques. It is covered increasingly with data entry, research, processing, modeling and reporting components of the icon in the form of easy-to-use in many datamining tools. Visual data mining process can create a data stream. In this paper, customer behavior is predicted in pages or products, using the history profile analysis and the navigation items are necessary to predict unknown features.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1997년도 봄 학술발표회 논문집
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• pp.27-34
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• 1997

In this paper, systematic and comprehensive approaches are suggested for the application of quantitative PRA techniques especially for those risk events that cannot be easily evaluated quantitatively In addition, dominant risk events are identified based on their occurrence frequency assessed by both actual survey of construction site conditions and the statistical data related with the probable accidents. Practical FTA(Fault Tree Analysis) and ETA(Event Tree Analysis) models are used for the assessment of the identified risks. When the risk events are lack of statistical data, appropriate Bayesian models incorporating engineering judgement and test results are also introduced in this paper. Moreover, a fuzzy probability technique is used for the quantitative risk assessment of those risk components which are difficult to evaluate quantitatively.

• 대한원격탐사학회지
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• 제7권1호
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• pp.45-67
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• 1991

An overview is given on stochastic techniques with which remotely sensed data may be used together with ground measurements for purposes of state estimation and prediction. They can explicitly account for spatiotemporal differences in measurement characteristics between ground measurements and remotely sensed data, and are suitable for highly variant space or space-time processes, such as atmosperic processes, which may be viewed as (containing) a random process. For state estimation of static ststems, optimal linear estimation is described. As alternatives, various co-kriging estimation techniques are also described, including simple, ordinary, universal, lognormal, disjunctive, indicator, and Bayesian extersion to simple and lognormal. For illustrative purposes, very simple examples of optimal linear estimation and simple co-kriging are given. For state estimation and prediction of dynamic system, distributed-parameter kalman filter is described. Issues concerning actual implemention are given, and with application potential are described.

• 한국지능시스템학회논문지
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• 제26권5호
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• pp.335-342
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• 2016

기 구축되어있는 베이지안 네트워크에서 다이나믹한 환경 변화가 발생 할 때, 관련된 베이지안 네트워크의 파라미터는 새롭게 형성된 데이터의 패턴에 적응하여 새로운 파라미터로 변경되어야 한다. 이때, 새로운 파라미터는 베이지안 네트워크의 인과관계를 고려하여 변경되어야 한다. 본 논문에서는 Expectation Maximization(EM)알고리즘과 Meta-Heuristics 기법 중 하나인 Harmony Search(HS)알고리즘을 이용한 다이나믹한 파라미터 업데이트 프레임웍을 제안한다. 일반적으로, EM 알고리즘은 숨겨진 파라미터를 추정하는데 유효한 알고리즘이지만 지역 최적값에 수렴한다는 단점을 가지고 있다. 이 문제를 해결하기 위해서 본 논문은 Maximum Likelihood Estimator(MLE)의 파라미터가 글로벌 최적값을 지향하도록 하기위하여 메타휴리스틱 방법론의 하나인 HS를 적용한다. 제안된 방법은 EM 알고리즘의 단점을 보완하고 글로벌 최적값에 수렴하는 MLE의 파라미터를 추정하여 다이나믹하게 변화하는 환경에서도 사용 가능한 베이지안 네트워크의 학습 및 전파프레임웍을 제시한다.

• 디지털융복합연구
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• 제11권3호
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• pp.345-352
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• 2013

최근 스마트 기기 사용자의 증가에 따라 모바일 음악에 대한 수요와 생산이 꾸준히 증가하고 있다. 이에 따라 대중화된 음악의 폭이 넓어지면서 사용자가 선호하는 음악에 대한 선택의 기준 또한 매우 다양해지고 복잡해지는 추세이다. 이러한 이유로 모바일 환경에서 사용자 개인이 선호하는 음악을 정교하게 추천하기 위한 지능적 음악 추천 기법에 대한 연구가 활발히 진행되고 있다. 그러나 기존의 음악 추천시스템은 청취로그를 이용한 단순 추천 방법을 사용하고 있어 사용자의 선호도를 제대로 고려하지 못하고 있다. 본 논문에서는 사용자의 선호도를 반영한 개인화된 적응형 음악 추천 시스템을 제안한다. 본 시스템에서는 계층적 의사결정 도구인 AHP를 이용하여 사용자의 개개인의 음악적 선호도를 반영한 음악 추천이 가능토록 하였으며, 베이지안 네트워크 기반의 사용자 피드백 통해 지속적인 사용자의 음악적 선호도를 반영하도록 하였다. 본 시스템의 성능을 평가하기 위해 12명의 실험자를 각각 3명씩 4그룹으로 나누어 실험하였으며 그 결과 87.5%의 추천 만족도를 얻었다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2021년도 학술발표회
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• pp.140-140
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• 2021

Urban flood management is a crucial and challenging task, particularly in developed cities. Therefore, accurate prediction of urban flooding under heavy precipitation is critically important to address such a challenge. In recent years, machine learning techniques have received considerable attention for their strong learning ability and suitability for modeling complex and nonlinear hydrological processes. Moreover, a survey of the published literature finds that hybrid computational intelligent methods using nature-inspired algorithms have been increasingly employed to predict or simulate the streamflow with high reliability. The present study is aimed to propose a novel approach, an ensemble tree, Bayesian Additive Regression Trees (BART) model incorporating a nature-inspired algorithm to predict hourly multi-step ahead streamflow. For this reason, a hybrid intelligent model was developed, namely GA-BART, containing BART model integrating with Genetic algorithm (GA). The Jungrang urban basin located in Seoul, South Korea, was selected as a case study for the purpose. A database was established based on 39 heavy rainfall events during 2003 and 2020 that collected from the rain gauges and monitoring stations system in the basin. For the goal of this study, the different step ahead models will be developed based in the methods, including 1-hour, 2-hour, 3-hour, 4-hour, 5-hour, and 6-hour step ahead streamflow predictions. In addition, the comparison of the hybrid BART model with a baseline model such as super vector regression models is examined in this study. It is expected that the hybrid BART model has a robust performance and can be an optional choice in streamflow forecasting for urban basins.

• 제어로봇시스템학회논문지
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• 제17권11호
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• pp.1095-1100
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• 2011

In this paper, PHM (Prognostics and Health Management) techniques are briefly outlined. Prognostics, being a central step within the PHM, is explained in more detail, stating that there are three approaches - experience based, data-driven and model based approaches. Representative articles in the field of prognostics are also given in terms of the type of faults. Model based method is illustrated by introducing a case study that was conducted to the crack growth of the gear plate in UH-60A helicopter. The paper also addresses the comparison of the OBM (Overall Bayesian Method), which was developed by the authors with the PF (Particle Filtering) method, which draws great attention recently in prognostics, through the study on a simple crack growth problem. Their performances are examined by evaluating the metrics introduced by PHM society.

• 인지과학
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• 제15권3호
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• pp.35-44
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• 2004

인터넷의 사용이 보편화됨에 따라 많은 양의 정보가 다양한 채널을 통해 제공되고 있다. 이와 더불어 사용자들은 효과적인 정보 제공 서비스를 원하고 있으며, 정보 교환에 도움을 주는 가상 대리자 역할의 대화형 에이전트의 연구가 활발히 진행되고 있다. 본 논문에서는 패턴매칭 기법과 베이지 안 네트워크 등의 인공지능 기법을 이용하여 사용자 질의 의도를 분석한 후 적절한 답변을 제공할 수 있는 질의응답 에이전트를 개발한다. 이때 유의어 사전을 이용한 키워드 데이터베이스를 구축함으로써 동의어 관계를 가진 유사 키워드 등의 사용자에 따른 다양한 지식표현 문제를 해결한다. 실제 의류 사이트를 소개하는 점 사이트에 적용해 봄으로써 그 가능성을 평가해 본다.

• Safety and Health at Work
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• 제8권2호
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• pp.206-211
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• 2017

Background: Self-reported low back pain (LBP) has been evaluated in relation to material handling lifting tasks, but little research has focused on relating quantifiable stressors to LBP at the individual level. The National Institute for Occupational Safety and Health (NIOSH) Composite Lifting Index (CLI) has been used to quantify stressors for lifting tasks. A chemical exposure can be readily used as an exposure metric or stressor for chemical risk assessment (RA). Defining and quantifying lifting nonchemical stressors and related adverse responses is more difficult. Stressor-response models appropriate for CLI and LBP associations do not easily fit in common chemical RA modeling techniques (e.g., Benchmark Dose methods), so different approaches were tried. Methods: This work used prospective data from 138 manufacturing workers to consider the linkage of the occupational stressor of material lifting to LBP. The final model used a Bayesian random threshold approach to estimate the probability of an increase in LBP as a threshold step function. Results: Using maximal and mean CLI values, a significant increase in the probability of LBP for values above 1.5 was found. Conclusion: A risk of LBP associated with CLI values > 1.5 existed in this worker population. The relevance for other populations requires further study.

• 대한안전경영과학회지
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• 제15권2호
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• pp.243-253
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• 2013

This research paper introduces the application and implementation of medical decision metrics that classifies medical decision-making into four different metrics using statistical diagnostic tools, such as confusion matrix, normal distribution, Bayesian prediction and Receiver Operating Curve(ROC). In this study, the metrics are developed based on cross-section study, cohort study and case-control study done by systematic literature review and reformulated the structure of type I error, type II error, confidence level and power of detection. The study proposed implementation strategies for 10 quality improvement activities via 14 medical decision metrics which consider specificity and sensitivity in terms of ${\alpha}$ and ${\beta}$. Examples of ROC implication are depicted in this paper with a useful guidelines to implement a continuous quality improvement, not only in a variable acceptance sampling in Quality Control(QC) but also in a supplier grading score chart in Supplier Chain Management(SCM) quality. This research paper is the first to apply and implement medical decision-making tools as quality improvement activities. These proposed models will help quality practitioners to enhance the process and product quality level.