• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 Proceedings of the Korea Automatic Control Conference, 11th (KACC); Pohang, Korea; 24-26 Oct. 1996
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• pp.275-278
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• 1996

This fault diagnosis system consists of qualitative models, qualitative interpreter, and inference engine. Qualitative models are formed by analysis of the relationships between faults and behaviors of sensor trends, which are described by state transition trees. Qualitative interpreter outputs confidence factors with three qualitative quantities which represent the states of sensor trends. And then, the possible faults are detected by inference module which matches the states of trends within a window size with the qualitative models using the well-known min-max operation.

• Korean Journal of Radiology
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• 제24권6호
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• pp.498-511
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• 2023

Objective: To evaluate the diagnostic performance of chest computed tomography (CT)-based qualitative and radiomics models for predicting residual axillary nodal metastasis after neoadjuvant chemotherapy (NAC) for patients with clinically node-positive breast cancer. Materials and Methods: This retrospective study included 226 women (mean age, 51.4 years) with clinically node-positive breast cancer treated with NAC followed by surgery between January 2015 and July 2021. Patients were randomly divided into the training and test sets (4:1 ratio). The following predictive models were built: a qualitative CT feature model using logistic regression based on qualitative imaging features of axillary nodes from the pooled data obtained using the visual interpretations of three radiologists; three radiomics models using radiomics features from three (intranodal, perinodal, and combined) different regions of interest (ROIs) delineated on pre-NAC CT and post-NAC CT using a gradient-boosting classifier; and fusion models integrating clinicopathologic factors with the qualitative CT feature model (referred to as clinical-qualitative CT feature models) or with the combined ROI radiomics model (referred to as clinical-radiomics models). The area under the curve (AUC) was used to assess and compare the model performance. Results: Clinical N stage, biological subtype, and primary tumor response indicated by imaging were associated with residual nodal metastasis during the multivariable analysis (all P < 0.05). The AUCs of the qualitative CT feature model and radiomics models (intranodal, perinodal, and combined ROI models) according to post-NAC CT were 0.642, 0.812, 0.762, and 0.832, respectively. The AUCs of the clinical-qualitative CT feature model and clinical-radiomics model according to post-NAC CT were 0.740 and 0.866, respectively. Conclusion: CT-based predictive models showed good diagnostic performance for predicting residual nodal metastasis after NAC. Quantitative radiomics analysis may provide a higher level of performance than qualitative CT features models. Larger multicenter studies should be conducted to confirm their performance.

• 수산해양교육연구
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• 제29권1호
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• pp.306-314
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• 2017

The purpose of this study is to explore the possibility of qualitative evaluation and applicable models in the evaluation area of educational program. To this end, the concept and characteristics of qualitative evaluation are examined, and grounded theory is selected as a suitable methodology for evaluation, and its characteristics and procedures are described. Because qualitative evaluation focuses on the spontaneous practice elements of the site, it can supplement the quantitative evaluation of the variables set in advance. The researcher presented the theory of qualification as a methodology for qualitative evaluation, aiming to extract the theory explaining the phenomenon among the qualitative methodologies.

• Journal of the Korean Statistical Society
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• 제3권2호
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• pp.103-115
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• 1974

During the last few years there has been an interest in models for qualitative attributes, where complex signifies that affection may be caused in two or more ways [1-3]. These models have in common the prediction of variable recurrence risks among families with given parental phenotpes. Segregation analysis has covered only a few cases [4,5]. The present paper extends segregation analysis to three complex models under two mode of ascertainment.

• 제어로봇시스템학회논문지
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• 제10권5호
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• pp.450-457
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• 2004

In this research, the automatic synthesis of knowledge models is proposed. which are the basis of the methods using qualitative models adapted widely in fault diagnosis and hazard evaluation of chemical processes. To provide an easy and fast way to construct accurate causal model of the target process, the Role-Behavior modeling method is developed to represent the knowledge of modularized process units. In this modeling method, Fault-Behavior model and Structure-Role model present the relationship of the internal behaviors and faults in the process units and the relationship between process units respectively. Through the multiple modeling techniques, the knowledge is separated into what is independent of process and dependent on process to provide the extensibility and portability in model building, and possibility in the automatic synthesis. By taking advantage of the Role-Behavior Model, an algorithm is proposed to synthesize the plant-wide causal model, Fault-Causality Graph (FCG) from specific Fault-Behavior models of the each unit process, which are derived from generic Fault-Behavior models and Structure-Role model. To validate the proposed modeling method and algorithm, a system for building FCG model is developed on G2, an expert system development tool. Case study such as CSTR with recycle using the developed system showed that the proposed method and algorithm were remarkably effective in synthesizing the causal knowledge models for diagnosis of chemical processes.

• 대한기계학회논문집
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• 제16권7호
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• pp.1351-1362
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• 1992

본 연구에서는 단순한 구간대신에 구간내에 제한된 형태의 가능성 분포를 갖 는 복합구간으로 학장하는 것이다. 그리고 이러한 가능성 분포는 퍼지 집합이론에서 사용되는 것처럼 일반적인 분포형태 전체를 사용하는 것이 아니라, 가능성 분포의 무 게중심만 정의하고 이 무게중심과 구간경계만을 사용하여 시스템 변수가 갖는 정성값 을 나타낸다. 이를 바탕으로 새로운 상태변화와 그 규칙을 정의함으로써 정성 모델 링과 시뮬레이션을 할 수 있는 정성 수학을 공식화하였다.이와 같은 방식으로 구한 정성 모델과 추론방법으로 기존의 논문에 나와 있는 시뮬레이션 결과와 비교하여 본 논문에서 제시한 정성해의 논리적 건전성(soundness)을 보였다.

• 디지털산업정보학회논문지
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• 제14권3호
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• pp.115-125
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• 2018

In order to examine the ways to improve the efficiency of R&D investment, this paper presents analysis on both quantitative and qualitative efficiency of R&D projects. As Korea's R&D investment has significantly increased in recent years, the efficiency of R&D investment has attracted attention. In this paper, a Data Envelopment Analysis(DEA) method is used to construct models for quantitative efficiency and qualitative efficiency analysis. Based on a cases of agricultural R&D projects of Korea, the efficiency of national R&D projects were analyzed and their quantitative and qualitative efficiencies are compared. As a result, statistically significant difference between quantitative and qualitative efficiency was found. Also, characteristics of Decision Making Units(DMUs) which can influence both quantitative and qualitative efficiency were identified. In particular, the stage of a R&D project has significant impact on R&D efficiency. This study suggests that in order to enhance R&D efficiency both quantitative and qualitative nature of outputs should be considered when measuring R&D efficiency.

• 대한수학교육학회지:수학교육학연구
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• 제27권1호
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• pp.23-49
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• 2017

본 연구는 중학교 3학년 학생 2명을 대상으로 공변 추론 수준에 관련된 두 이론(Carlson et al.(2002), Thompson, & Carlson(2017))을 그래프 유형(양적 그래프, 질적 그래프)에 따라 분석하였다. 이에 대한 연구결과로 양적 그래프 과제에서 Thompson과 Carlson(2017)은 Carlson 외(2002)보다 학생의 수준을 세분화하였으며, 질적 그래프 과제에서 Thompson과 Carlson(2017)은 학생 수준을 범주화하기 어려웠지만, Carlson 외(2002)는 학생의 수준을 자세히 파악할 수 있었다. 이와 같은 연구결과는, 학생들의 공변 추론을 파악하는 데 있어 양에 따른 수치적 접근의 분석뿐만 아니라 두 양의 공변 양상을 비수치적으로 파악하는 질적 접근의 분석도 중요함을 시사하며, 또한 Thompson과 Carlson(2017)이 양에 따른 수치적 접근을 분석하는 데 있어 중요한 방법이며 Carlson외(2002)가 비수치적으로 파악하는 질적 접근을 분석하는 데 있어 중요한 방법임을 시사한다.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2001년도 추계학술발표논문집 (상)
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• pp.363-366
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• 2001

It is very difficult to maintain the performance of estimation models for the new breed of projects since the computing environment changes so rapidly in terms of programming languages, development tools, and methodologies. So, we propose to use the relevant cases for a neural network model, whose cost is the decreased number of cases. To balance the relevance and data availability, the qualitative input factors are used as criteria of data classification. With the data sets that have the same value for certain qualitative input factors, we can eliminate the factors from the model making reduced neural network models. So we need to seek the optimally reduced neural network model among them. To find the optimally case-selective neural network, we propose the search techniques and sensitivity analysis between data points and search space.

• Nuclear Engineering and Technology
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• 제53권2호
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• pp.376-385
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• 2021

Probabilistic risk assessment (PRA) has improved its elemental technologies used for assessing external events since the Fukushima Daiichi Nuclear Power Station Accident in 2011. HRA needs to be improved for analyzing tasks performed under extreme conditions (e.g., different actors responding to external events or performing operations using portable mitigation equipment). To make these improvements, it is essential to understand plant-specific and scenario-specific conditions that affect human performance. The Nuclear Risk Research Center (NRRC) of the Central Research Institute of Electric Power Industry (CRIEPI) has developed an HRA guide that compiles qualitative analysis methods for collecting plant-specific and scenario-specific conditions that affect human performance into "narratives," reflecting the latest research trends, and models for analysis of tasks under extreme conditions.