• 한국해양공학회지
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• 제34권3호
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• pp.167-179
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• 2020

Recently, the increasing importance of artificial intelligence (AI) technology has led to its increased use in various fields in the shipbuilding and marine industries. For example, typical scenarios for AI include production management, analyses of ships on a voyage, and motion prediction. Therefore, this study was conducted to predict a response amplitude operator (RAO) through AI technology. It used a neural network based on one of the types of AI methods. The data used in the neural network consisted of the properties of the vessel and RAO values, based on simulating the in-house code. The learning model consisted of an input layer, hidden layer, and output layer. The input layer comprised eight neurons, the hidden layer comprised the variables, and the output layer comprised 20 neurons. The RAO predicted with the neural network and an RAO created with the in-house code were compared. The accuracy was assessed and reviewed based on the root mean square error (RMSE), standard deviation (SD), random number change, correlation coefficient, and scatter plot. Finally, the optimal model was selected, and the conclusion was drawn. The ultimate goals of this study were to reduce the difficulty in the modeling work required to obtain the RAO, to reduce the difficulty in using commercial tools, and to enable an assessment of the stability of medium/small vessels in waves.

• Structural Engineering and Mechanics
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• 제49권1호
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• pp.23-40
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• 2014

In this article, using finite element method of analysis (FEM), behavior of the endplate moment connection subjected to axial force and bending moment is investigated. In the FEM model, all the nonlinear characteristics such as material, geometry, as well as contact have been included. First, in order to verify the numerical model of the connection, an analysis of the endplate moment connection conducted without the application of the axial force. Results obtained from FEM indicating a close and good correlation with the experimental results. Then to investigate the influence of the axial forces, the connections subjected to axial forces as well as the bending moment are analyzed. To observe the overall effect of these actions, the momentaxial force interaction diagrams are drawn. It is observed that the presence of axial force even in a small value can change the behavior of the connection significantly. It is also shown that the axial forces can alter the failure mode of the connection; and therefore it could result in a different than the predicted moment capacity of the connection.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2007년도 추계 종합학술대회 논문집
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• pp.719-723
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• 2007

SK커뮤니케이션즈가 운영하는 온라인 교육 사이트 이투스(www.etoos.com)가 웹2.0 시대에 맞춰 수강생들의 참여 공간을 늘리고, 온라인을 통해 '학습'과 '재미'를 강화한 개방형 홈페이지로 2007년 초 전면 개편되는 등 기존의 e-Learning 콘텐츠 회사들이 웹2.0 기반의 비즈니스 모델을 통해 콘텐츠 차별화를 꾀하려는 움직임이 매우 활발하다. 본 연구에서는 웹2.0 시대를 맞은 e-Learning 콘텐츠의 현황을 대표적인 중고등 교육 e-Learning 콘텐츠를 중심으로 분석해 보고, 차세대 e-Learning의 발전 방향을 효과적인 피드백이 제공되는 학습자 중심의 콘텐츠 개발과 웹2.0의 본질에 입각한 집단 지성을 이끌어내는 데서 찾고, 'e-Learning 콘텐츠 내의 virtual 개인 과외 선생님 community 형성에 관한 프로젝트'를 제안해 본 것이다.

• 정보관리학회지
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• 제24권4호
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• pp.173-189
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• 2007

정보시스템을 사용하는 이용자들의 만족지수를 측정함으로써 시스템 투자 대비 효과를 정성적으로 측정할 수 있을 뿐만 아니라 향후 시스템의 효율성 및 시스템 개선노력을 위한 방안도 도출할 수 있다. 본 연구에서는 정보시스템의 이용자만족지수 모델을 제안하고 대표적인 정보시스템들의 이용자만족지수를 측정함으로써 이들 시스템 운영자 및 관리자들에게 시스템 만족도 제고 및 효율성 향상을 위한 개선방안을 제시하고자 한다. 본 연구의 수행을 위해 대표적인 정보시스템들을 대상으로 웹 설문조사를 실시하였으며, 분석결과를 바탕으로 만족지수를 산출하고 Matrix 분석을 통해 시스템 개선방안을 도출하였다.

• 응용통계연구
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• 제22권6호
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• pp.1167-1176
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• 2009

항만이나 공항의 소유구조에 대한 효율성 분석은 지금까지 서로 엇갈리는 결과를 제시하고 있다. 즉, 민영화 또는 공영화로 인한 효율성 효과가 자료 또는 분석 방법에 따라서 일치된 결과를 보여주지 않고 있다. 본 논문은 국내의 항만이 포함된 국제 항만 교역데이터베이스를 기반으로 베이지안 확률적 프런티어 모형을 적용하여 항만의 소유 구조에 따른 효율성 분석을 하였다. 소유 구조는 Tongzon과 Heng (2005)의 방법을 따랐으며 제안된 몇 가지 모형과 그들의 모형을 DIC 통계량을 이용하여 비교하였다. 베이지안 추론에 필요한 MCMC 방법은 Griffin과 Steel (2007)에서 소개된 WinBUGS 프로그램을 이용하여 구현하였다.

• Journal of Magnetics
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• 제19권4호
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• pp.315-322
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• 2014

In this work, Artificial Neural Network (ANN) was used to model the dynamic behavior of ferromagnetic hysteresis derived from performing the mean-field analysis on the Ising model. The effect of field parameters and system structure (via coordination number) on dynamic critical points was elucidated. The Ising magnetization equation was drawn from mean-field picture where the steady hysteresis loops were extracted, and series of the dynamic critical points for constructing dynamic phase-diagram were depicted. From the dynamic critical points, the field parameters and the coordination number were treated as inputs whereas the dynamic critical temperature was considered as the output of the ANN. The input-output datasets were divided into training, validating and testing datasets. The number of neurons in hidden layer was varied in structuring ANN network with highest accuracy. The network was then used to predict dynamic critical points of the untrained input. The predicted and the targeted outputs were found to match well over an extensive range even for systems with different structures and field parameters. This therefore confirms the ANN capabilities and indicates the ANN ability in modeling the ferromagnetic dynamic hysteresis behavior for establishing the dynamic-phase-diagram.

• 디지털콘텐츠학회 논문지
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• 제13권4호
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• pp.625-629
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• 2012

NGN 운용과정의 품질 보증을 위해 어떤 체계하에서 품질이 테스트 되어야 하는지 방법론을 도출하기 위해서 멀티미디어 트래픽을 중심으로 NGN 품질측정 프레임워크를 제시한다. 테스트베드는 NGN 운용과정에서 QoS 측정 메트릭스, 측정구간과 측정계위, 측정도구, 측정장비, 측정방법 및 측정결과 분석에 대한 일련의 프로세스와 방법론을 모델화한다. 이 모델은 향후 NGN 품질보증 활동에 활용토록 한다. 통신서비스 품질은 스스로 보장되지 않으며 끊임없이 측정되고 관리될 때에 만 품질 목표수준 확보가 가능하다. NGN 네트워크기술 패러다임 중요성을 감한할 때 NGN 운용상의 품질관리에 대한 연구는 앞으로 활발하게 추진되어야 할 핵심 소재이다.

• Child Health Nursing Research
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• 제24권1호
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• pp.37-47
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• 2018

Purpose: The purpose of this study was to construct a model to explain the parenting satisfaction associated with the role transition of older mothers with preschool children. Methods: The participants of this study were mothers of 3- to 6-year-old children who gave birth after 35 years of age, and were drawn from 16 child care centers and 8 kindergartens in 4 administrative districts of B city. Data were analyzed using SPSS for Windows version 22.0 and AMOS for Windows version 22.0. Results: Parental stress, mother-child interactions, parental beliefs regarding personality, and socioeconomic status (income, education, and occupation) had direct effects on parenting satisfaction. Social support also showed direct and indirect effects. Among the sub factors of child temperament, sociability had a significant effect. These variables explained 57.4% of the variation in parenting satisfaction. Conclusion: The results of this study will contribute to the development of effective programs to enhance the parenting satisfaction of older mothers, and will help older mothers through the role transition necessary for the growth of their children.

• 한국비블리아학회지
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• 제21권2호
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• pp.97-110
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• 2010

어린이 서비스의 전문성 확보를 위한 체계적이고 실질적인 교육을 위하여 어린이전문사서의 교육과정 모형을 개발하였다. 문헌연구 및 이론 분석, 설문조사, 문헌정보학과 교과과정 분석 결과에 기초한 어린이전문사서 교육과정 모형은 어린이사서, 어린이, 자료, 서비스, 운영 및 관리등 5개 영역으로 구분하였다. 교육과정은 '교양과정'과 '계속전문과정'으로 구분하여 관련 교과목을 개설하고, 교양과정은 총 90시간, 계속전문과정은 총 165시간으로 편성하였다. 교과목의 특성에 따라 일부 교과목은 이론수업과 실행 수업을 병행할 수 있도록 학점을 분리하여 구성하였다. 교육방법과 기간은 상시 개설되는 온라인 강좌와 특정 집중교육 기간 동안 이루어지는 오프라인 수업이 병행되는 통합형으로 제안되었다.

• Journal of Information Technology Applications and Management
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• 제11권1호
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• pp.1-14
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• 2004

Increasing affectability of high-speed Internet and convenient access devices has made the Internet a major source of information search and sharing. As the provision of information has rapidly becomes an important and viable business model, the objective utility and marketability of information contents have become a focus of interest among many academicians and managers. Researchers have traditionally focused on the design of the interface, availability of resources, network accessibility, the format of web sites and their underlying systems. However, the usefulness of contents has been left as a little explored issue. To correctly diagnose and pursue the viability of contents provision business a shift of perspective is required : a shift from technology-oriented perspective toward user-oriented perspective, and a shift from form and design focus toward content focus. This research attempted to analyze consumer-oriented information quality in a more systematic way by focusing on a limited domain travel-related information contents. We proposed a relationship among consumers'behavior, characteristics of information, and the values of information measured by users. An empirical examination of the model was performed using a survey on Internet users in Korea. Implications are drawn for managers responsible for creating marketable contents.