• 한국전기전자재료학회논문지
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• 제15권1호
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• pp.67-74
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• 2002

A phosphor for Plasma Display Panel, BaMgAl$_{10}$ O$_{17}$ :Eu$^{2+}$, showing a blue emission band at about 450nm was prepared by a solid-state reaction using BaCO$_3$, $Al_2$O$_3$, MgO, Eu$_2$O$_3$ as starting materials wish flux AlF$_3$. The study of the behaviour of Eu in BAM phosphor was carried out by the photoluminescence spectra and the Rietveld method with X-ray and neutron powder diffraction data to refine the structural parameters such as lattice constants, the valence state of Eu, the preferential site of Mg atom and the site fraction of each atom. The phenomenon of the concentration quenching was abound 2.25~2.3wt% of Eu due to a decrease in the critical distance for energy transfer of inter-atomic Eu. Through the combined Rietveld refinement, R-factor, R$_{wp}$, was 8.11%, and the occupancy of Eu and Mg was 0.0882 and 0.526 at critical concentration. The critical distance of Eu$^{2+}$ in BAM was 18.8$\AA$ at 2.25% Eu of the concentration quenching. Furthermore, c/a ratio was decreased to 3.0wt% and no more change was observed over that concentration. The maximum entropy electron density was found that the modeling of $\beta$-alumina structure in BaMgAl$_{10}$ O$_{17}$ :Eu$^{2+}$correct coincided showing Ba, Eu, O atoms of z= 1/4 mirror plane.e.ane.e.

• 수산해양교육연구
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• 제24권4호
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• pp.543-558
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• 2012

This is a qualitative study of pre-service teachers' experiences in a teaching practicum course which attempted to identify the characteristics of the course that has been recently revised as professional education course. Data were collected from college students who took the professional education courses including the teaching practicum course by using both a survey on the opinions and suggestions of the students on the teaching practicum and a in-depth interview with 12 students of them. The results are as follows. First, pre-service teachers' perception of a teaching practicum course was divided into two sides : functional side and sociocultural side. The formal is that the professional education courses significantly handed to discipline practical jobs related to educational administration. The latter is that the professional education courses significantly handed to deal for teachers like pay step, extra pay, vacation, and leave of absence. Second, the pre-service teachers had suggestions that were divided into the 'curriculum content' and the 'instructional method'. For instance, regarding the 'curriculum content' they suggested such things needed as 'lessening and differentiation of content, sensitive about the scene, and lesson hands-on', and as for the 'instructional method' they suggested such things needed as actively 'doing, participating, assessing, coursework participating'. Based on these results, I have comprehended the pre-service teachers' positive response. Untill now, we have perceived that the professional education courses is excessively theory-oriented one. But a teaching practicum course is different. Meanwhile, It is not identify what the teaching practicum course as teaching refinement education course is. Due to this cause, I have comprehended that 'curriculum content' and the 'instructional method' is plunged in confusion. As pointed out this, I did concrete proposals in response to such a confusion. This proposals have helped decided on a direction of a teaching practicum course.

• 전자공학회논문지CI
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• 제38권5호
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• pp.37-43
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• 2001

인터넷이 널리 이용되면서 네트워크나 호스트에 대한 불법적인 침입은 많은 위험요소가 되고 있다. 이러한 침입을 탐지하기 위하여 통계적기법, 데이터마이닝기법, 유전자 알고리즘/프로그래밍 기법 등을 이용한 이상현상 탐지모델들이 많이 제안되어 왔으나 새로운 유형의 침입에 대해서는 탐지능력이 떨어지는 단점이 있다. 본 논문에서는 THRE KBANN을 이용한 이상현상탐지모델을 제안하였는데, 이는 연속학습을 할 수 있도록 지식기반신경망을 개선한 것이다. 이 모델을 실험적 자료에 적용한 결과를 데이터마이닝기법을 적용한 경우와 비교하여 성능평가를 하였다. 그리고 새로운 침입유형을 탐지하기 위한 연속학습에 대한 성능도 평가하였다.

• 인터넷정보학회논문지
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• 제20권3호
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• pp.85-92
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• 2019

In this paper, we extract the quantitative relation data of activities from the workflow event log file recorded in the XES standard format and connect them to rediscover the workflow process model. Extract the workflow process patterns and proportions with the rediscovered model. There are four types of control-flow elements that should be used to extract workflow process patterns and portions with log files: linear (sequential) routing, disjunctive (selective) routing, conjunctive (parallel) routing, and iterative routing patterns. In this paper, we focus on four of the factors, disjunctive routing, and conjunctive path. A framework implemented by the authors' research group extracts and arranges the activity data from the log and converts the iteration of duplicate relationships into a quantitative value. Also, for accurate analysis, a parallel process is recorded in the log file based on execution time, and algorithms for finding and eliminating information distortion are designed and implemented. With these refined data, we rediscover the workflow process model following the relationship between the activities. This series of experiments are conducted using the Large Bank Transaction Process Model provided by 4TU and visualizes the experiment process and results.

• Journal of Information Technology Applications and Management
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• 제26권1호
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• pp.39-51
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• 2019

As data grows rapidly, the provision of appropriate information needed by individuals has become an area of new services, and customized services which is enabling the analysis of optimal services through collecting, storing, and analyzing personal data are emerging in many fields. However, due to the characteristics of customized services based on various information collected by customers during the use of the service, the problem of privacy infringement is raised at the same time, and many studies are being actively conducted to solve this problem. This study seeks to explore how the customer's in-depth and customized services has an impact on their customers, which has not been derived from quantitative research using the grounded theory methodology. Through this, 84 concepts, 33 subcategories, 13 Categories and paradigm models were derived. In addition, 'Understanding and acceptance of online behavioral advertising (OBA)' was derived as a core category, and finally, acceptance types of OBA were classified into 'positive acceptance type', 'indifferent type', 'calculating type', and 'active resistance type' based on the key categories. This study divides the acceptance types of online behavioral advertising through the emotions and behaviors of the consumers throughout the procedure of online behavioral advertising experiences. In addition to the statistical and quantitative information currently used for providing behavioral advertising, it provides new criteria to reflect the refinement of behavioral advertising and personal tendencies or characteristics.

• Child Health Nursing Research
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• 제29권3호
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• pp.182-194
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• 2023

Purpose: This study analyzed research trends in infant and toddler rearing behavior among family caregivers over a 10-year period (2010-2021). Methods: Text network analysis and topic modeling were employed on data collected from relevant papers, following the extraction and refinement of semantic morphemes. A semantic-centered network was constructed by extracting words from 2,613 English-language abstracts. Data analysis was performed using NetMiner 4.5.0. Results: Frequency analysis, degree centrality, and eigenvector centrality all revealed the terms ''scale," ''program," and ''education" among the top 10 keywords associated with infant and toddler rearing behaviors among family caregivers. The keywords extracted from the analysis were divided into two clusters through cohesion analysis. Additionally, they were classified into two topic groups using topic modeling: "program and evaluation" (64.37%) and "caregivers' role and competency in child development" (35.63%). Conclusion: The roles and competencies of family caregivers are essential for the development of infants and toddlers. Intervention programs and evaluations are necessary to improve rearing behaviors. Future research should determine the role of nurses in supporting family caregivers. Additionally, it should facilitate the development of nursing strategies and intervention programs to promote positive rearing practices.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2000년도 추계 학술발표회 논문집 Proceedings of EESK Conference-Fall 2000
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• pp.251-260
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• 2000

Seismic performance evaluation systems require rational classification of structure systems, proper evaluation criteria, and their scoring index for synthesis. Current seismic performance systems need expert judgments based on collection of available data, approximate analysis of important items, and various scoring system. This study presents a three-step seismic performance evaluation system for building structures in Korea. Each evaluation step determines the seismic performance and the method depends on the degree of refinement of analysis. The preliminary step evaluation involves the global attributes of structures such as vertical irregularity, asymmetric plan, redundancy, and age of structures. The second step requires an elastic analysis for estimation of forces acting on critical sections and checks the strength and ductility. The final step requires inelastic capacity of structures. Each stephas own evaluation scheme with proper weighing factor dependent on the importance and consequence. This study applies the fuzzy theory to a scoring method that synthesizes the individual quantity to a representative value.

• 한국의류학회지
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• 제36권6호
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• pp.601-615
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• 2012

In this study, two representative measures in the job-focused approach and the employee-focused approach of emotional labor are explored to examine dimensionality and the predictability of each emotional labor measure on key consequences that include job stress, customer orientation, and job satisfaction. Data obtained from 193 department store apparel saleswomen were submitted for analysis. The results show that the emotional dissonance and emotional effort of the Kruml and Geddes measure are good predictors for job stress, customer orientation, and job satisfaction. In a test of the Davies measure, job stress is predicted by emotional dissonance and frequency while customer orientation is predicted by duration, variety, and the frequency of emotional expression in jobs. Duration is also a key predictor for job satisfaction. The result confirm the dimensionality and predictability of two emotional labor measures as well as suggests the need for the careful selection and refinement of appropriate measures according to consequences.

• 응용통계연구
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• 제26권5호
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• pp.785-796
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• 2013

News impact curves(NIC)는 1993년 Engle와 Ng에 의하여 제시되었으며, 이는 시계열 자료에서 발생하는 변동성을 시각적으로 나타내는데 용이하다. 본 논문에서는 기존의 NIC에서 더 나아가, 2차원 NIC(two dimensional NIC)와 주성분 NIC(PCA in NIC)를 제안하였으며, KOSDAQ 자료에서 적용하여 보았다.

• Geomechanics and Engineering
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• 제16권4호
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• pp.423-433
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• 2018

A three-dimensional model is constructed to simulate water infiltration in an unsaturated slope from a leaking pipe. Adaptive mesh refinement and time stepping are used, assisted by an automatic procedure for progressive steepening of the hydraulic property function for better convergence. The model is justified by comparing the simulated results with experimental data. Steady-state flow is investigated considering various pipe water pressures, locations and sizes of the opening, and soil layering. The opening size significantly affects the soaked zone around the pipe. Preferential flow dominates along the pipe longitudinal direction in the presence of a loose backfill around the pipe.