• The Korean Journal of Applied Statistics
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• v.30 no.3
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• pp.323-334
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• 2017

We note that the dynamics of realized volatilities (RVs) are near the boundary between stationarity and non-stationarity because RVs have persistent long-memory and are often subject to fairly large outlying values. To forecast realized volatility, we consider a new method that adaptively use models with and without unit root according to the abnormality of observed RV: heterogeneous autoregressive (HAR) model and the Integrated HAR (IHAR) model. The resulting method is called the IHAR-O-HAR method. In an out-of-sample forecast comparison for the realized volatility datasets of the 3 major indexes of the S&P 500, the NASDAQ, and the Nikkei 225, the new IHAR-O-HAR method is shown superior to the existing HAR and IHAR method.

• Journal of Digital Contents Society
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• v.19 no.3
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• pp.561-567
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• 2018

In this paper, we apply this method to the entire process of smart disaster safety management based on the $4^{th}$ industrial revolution to minimize human, social, economic and environment damage from accidents and disasters, prevention evaluation and disaster information collection analysis and real-time detection of field situation. Prevention of $5^{th}$ generation communication system by analysis, contrast by education and training using virtual reality and augmented reality disaster safety management decision support system intelligent robot for recovery, disaster, discovery, reconnaissance relief, and scale analysis of damages were proposed.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.05a
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• pp.522-524
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• 2015

A USB memory stick became common for secondary storage Unit.. But USB memory stick has critical problems as well. Such as personal information data leakage due to easy loss of the portable device. Therefore, User increased Repurchases of USB memory stick, and damage case of personal and company information data leakage increased. In this study, to prevent such loss and stolen, we propose Smart USB memory stick based on Bluetooth. Smart USB memory stick support the security and prevent the loss.

• Journal of Digital Contents Society
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• v.7 no.2
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• pp.117-124
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• 2006

In ubiquitous computing environment, a user can access their personalized services at anytime, anywhere, through any possible mobile or fixed terminals in a secure way. If the user wants to move to a different location, they need to stop the video play at the current location and makes a new request at the new location. As well, the user needs to manually search for the last frame to be seen at the previous location. In this paper, we proposed an implementation of multimedia contents streaming service mobility by user's location tracking. User can play video seamlessly while moving from one machine to another along the user's moving trail.

• Proceedings of the Korean Society of Computer Information Conference
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• 2010.07a
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• pp.19-21
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• 2010

컴퓨터 성능의 급속한 발전으로 언어 학습에 컴퓨터를 이용하려는 시도는 이제 새로운 언어 교수법 차원으로 발전하는 실정이다. 이에 따라 컴퓨터를 이용한 학습이 더욱 강조되면서, 많은 학습 프로그램이 개발되고 있다. 그러나, 기존 영어 단어 학습 시스템은 학습자에게 지나치게 많은 단어들을 단순한 방법을 통해서 학습하게 함으로써 심리적 부담을 주고 있다. 심리언어학에서는 언어 이해의 과정이 단순히 제시된 것을 그대로 받아들이는 수용의 과정이 아니라 학습자가 이미 보유한 경험과 개념을 근거로 활성망의 확산을 통해 적절한 관계를 찾는 역동적 능동적 과정이라는 이론이 있다. 본 논문에서는 언어 학습 이론을 바탕으로 단어들 사이의 관계를 부각시킴으로써 추론과 기억에 도움을 주는 영어 단어 학습 시스템을 제안한다. 본 시스템은 단어들 간의 관계를 정의한 단어 관계 망을 중심으로 단어 학습 순서를 결정할 수 있고, 이미지 및 게임 기능을 지원하여 단어학습의 흥미를 유발하는 특징이 있다.

• Review of KIISC
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• v.17 no.5
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• pp.15-24
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• 2007

모바일 및 웹 어플리케이션의 통합으로 인해 모바일 사용자들이 접근할 수 있는 서비스의 수는 크게 증가했지만 사용자들은 여러 개의 사용자 이름과 패스워드를 관리해야하는 어려움을 가지고 있다. 이와 유사한 상황은 다양한 종류의 개인장비, 무선 센서, 서버, 서비스 그리고 댁내에서 네트워크화 된 기기들로 구성된 흠 네트워크 환경으로 확장될 수 있다. 최근 디지털 홈 워킹 그룹 (DHWG: Digital Home Working Group)은 보안 강화를 위해 사용자와 기기에 대한 호환성 있는 인증 및 인가 메커니즘을 위한 프레임워크를 준비할 것을 권고하고 있다. 인터넷, 인트라넷 그리고 댁내에 분산된 자원들을 사용하기 위해 각 어플리케이션에 대한 사용자의 인증 및 인가는 반드시 필요하지만 이는 보안 관리와 시스템성능 측면에서는 커다란 부담이 된다. 본 논문에서는 XML기반의 단일인증기술 표준인 SAML (Security Assertion Markup Language)을 이용한 단일인증 아키텍처를 제안한다. 제안된 아키텍처를 기반으로 모바일 및 유비쿼터스 서비스 환경에서 모바일과 홈 기기간에 서로 다른 개체의 인증 및 인가 프로파일 정보의 교환을 가능하게 하므로 분산 환경에서의 보안 관리를 강화할 수 있다. 특히 제안된 아키텍처에서는 고도의 연산능력을 필요로 하는 보안정보의 전자서명 및 암복호 작업을 유선환경에 구성된 고성능의 기기로 전가하고 모바일 기기는 사용자의 인증을 검증할 수 있는 작은 문자열 형태의 artifact를 보유하고 이를 사용자의 인증에 이용함으로써 낮은 컴퓨팅 능력과 기억용량의 한계 같은 모바일 기기의 성능적인 제약을 극복할 수 있게 한다.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2001.06a
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• pp.383-389
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• 2001

된 연구에서 대상으로 하고 있는 LG 정유 광양항 제품부두는 7 선석(Berth)에 재화중량(DWT) 300톤에서 48000 톤의 선박까지 다양한 선박이 이용하고 있으며, 해상의 기상상태에 따른 선박 입출향 통제 지침 설정이 어렵고, 현재 사용하고 있는 지침의 근거가 명확하지 않아 현재의 부두 운영이 비효율적이거나 안전성이 결여되어 있다고 할 수 있다. 따라서 이를 개선하기 위한 합리적인 부두운영 제한조건 개발이 절실히 요구되었다. 본 논문에서는 대상 부두의 특성, 대상 선박의 특성, 하중상태, 선박 운항자의 특성 등을 고려하여 해상/기상 상황(바람, 조류 및 파랑)에 따른 부두 입출항 가능 여부를 정량적으로 판단하고, 안전성 향상 방안을 제시할 수 있는 의사결정 시스템을 개발하고 5번, 7번 선석을 대상으로 이를 검증하였다. 여기서는 입출항 여부를 정량적으로 판단하여 결과를 제시하기 위해서 유전적 프로그래밍(Genetic Programming)을 이용한 기계학습 방법을 이용하였으며, GP의 방대한 계산량을 줄이기 위한 가중 선형 연상 기억(Weighted Linear Associative Memory: WLAM) 방법의 도입 및 전역 최적점을 쉽게 찾기 위한 Group of Additive Genetic Programming Trees(GAGPT)를 도입함으로써 학습 성능을 개선하였다.

• Journal of the Korean Geographical Society
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• v.52 no.1
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• pp.25-53
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• 2017

The ultimate goal of this research is to examine the geographical characteristics of therapeutic spaces where have been appeared in Wa-dong and Gojan-dong, Ansan-si after the disaster of the MV Sewol. As looking into the inside, the aim of the therapeutic spaces, which cover each target group (victims) individually, is various and different because the disaster of the MV Sewol generated various direct and indirect victims requiring healing. The therapeutic spaces are estimated at about 10 organizations and are leaded by private agents predominantly. Furthermore, the therapeutic spaces are located near, but are aside from Danwon high school where many students are reported killed and injured in the incident. And the therapeutic spaces provide simple and repetitive diversions, for example, having a meal, knitting and studying, rather than special programs to restore a broken daily life to the original state. On the basis of such a background, the geographical characteristics of the therapeutic spaces related to the disaster of the MV Sewol can be summarized as follows; first, it seems that target groups accept the therapeutic spaces as the concept of place gradually. Even though most of the therapeutic spaces were suggested by third parties at first, target groups are involved in the management and recollection of their own therapeutic spaces as well as the plan for a future direction now; and consider the therapeutic spaces as exclusive properties. Second, the disaster of the MV Sewol have embedded collective trauma to not only direct victims, but extensive groups such as parents, brothers and sisters, relatives, friends and neighbors as noted earlier. Therefore, the therapeutic spaces support comprehensive target groups; but each therapeutic space is not overlapped each other. However, to solve collective trauma in a local community effectively, the therapeutic spaces are networked closely and build a regular cooperative system. Third, a continuous memory is mentioned as an important point to overcome collective trauma, but some phenomena such as fatigue and conflict with neighbors, out-migrants and a faded atmosphere as time passes act as risk factors in Ansan-si. To keep a continuous memory, the therapeutic spaces attempt the recovery of local communities and devise various events, for example, cultural performances; furthermore, are closely connected with external organizations.

• Korean Security Journal
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• no.11
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• pp.203-226
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• 2006

A highly sophisticated expertise and systematic and integrated management of security operation are essential for a crowded stadium. a special object of security guarding. Nonetheless, the recent incident in a singing concert hall reveals the overall problem like the lacking safety management system. lacking deployment of professional security personnel, absence of safety manuals and safety measures, as well as the lack of professionalism of private sector security companies. In this study, we presented three categories that needed improvement, like the legal and institutional improvement, improvement of policy and improvement of operation which are required to set up the model to operate the optimal private sector security duties. For the revision of law and institution for a better and more desirable method, we discussed the revision of related laws and regulations pursuant to the security operation at places where events are held, including the revision of law on security guarding work, regulation on common housing management, uniformity of security guarding, and law on performance. For the improvement of policies, we discussed the introduction of security consultants, strengthening the security instructor system, expansion of relevant organizations, establishment of mutual cooperation, privatization of profitable events, improvement of awareness about the security activities provided by private sector, policy for the professionalism of private security operation, expansion of security exhibition and seminar. For the improvement of operation. we discussed professional security techniques. such as the technique of security consulting, the application of CPTED technique, the technique for the integration of system, the method of operation, the establishment of a system to support public security operations and volunteers, establishment of a manual for security guarding performance, modernization and high tech-oriented equipment, organization of security guarding entity in which the industry, academic society and government participates together.

• Fashion & Textile Research Journal
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• v.24 no.6
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• pp.667-685
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• 2022

This paper aims to investigate 4D printing materials for soft robots. 4D printing is a targeted evolution of the 3D printed structure in shape, property, and functionality. It is capable of self-assembly, multi-functionality, and self-repair. In addition, it is time-dependent, printer-independent, and predictable. The shape-shifting behaviors considered in 4D printing include folding, bending, twisting, linear or nonlinear expansion/contraction, surface curling, and generating surface topographical features. The shapes can shift from 1D to 1D, 1D to 2D, 2D to 2D, 1D to 3D, 2D to 3D, and 3D to 3D. In the 4D printing auxetic structure, the kinetiX is a cellular-based material design composed of rigid plates and elastic hinges. In pneumatic auxetics based on the kirigami structure, an inverse optimization method for designing and fabricating morphs three-dimensional shapes out of patterns laid out flat. When 4D printing material is molded into a deformable 3D structure, it can be applied to the exoskeleton material of soft robots such as upper and lower limbs, fingers, hands, toes, and feet. Research on 4D printing materials for soft robots is essential in developing smart clothing for healthcare in the textile and fashion industry.