• 한국정밀공학회지
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• 제29권9호
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• pp.938-945
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• 2012

To design and estimate material failures of Type III pressure vessels, which have excellent stability and performance, various modeling techniques have been introduced. This paper provided a hybrid modeling technique composed of ply-based modeling for a cylinder part and laminate-base modeling technique for a dome part for enhancing modeling efficiency. The ply-based modeling technique provided accurate ply stresses directly for predicting material failure, on the other hand, additional manipulations in stress calculations, which may cause some errors, were needed for the case of the laminate-based modeling technique. The ply stresses in fiber, transverse and in-plane shear directions were compared with the corresponding material strengths to predict material failure.

• 한국정보시스템학회지:정보시스템연구
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• 제30권1호
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• pp.45-64
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• 2021

Purpose The traditional topic modeling technique makes it difficult to distinguish the semantic of topics because the key words assigned to each topic would be also assigned to other topics. This problem could become severe when the number of online reviews are small. In this paper, the extended model of topic modeling technique that can be used for analyzing a small amount of online reviews is proposed. Design/methodology/approach The extended model of being proposed in this paper is a form that combines the traditional topic modeling technique and the Word2Vec technique. The extended model only allocates main words to the extracted topics, but also generates discriminatory words between topics. In particular, Word2vec technique is applied in the process of extracting related words semantically for each discriminatory word. In the extended model, main words and discriminatory words with similar words semantically are used in the process of semantic classification and naming of extracted topics, so that the semantic classification and naming of topics can be more clearly performed. For case study, online reviews related with Udo in Tripadvisor web site were analyzed by applying the traditional topic modeling and the proposed extension model. In the process of semantic classification and naming of the extracted topics, the traditional topic modeling technique and the extended model were compared. Findings Since the extended model is a concept that utilizes additional information in the existing topic modeling information, it can be confirmed that it is more effective than the existing topic modeling in semantic division between topics and the process of assigning topic names.

• 정보처리학회논문지C
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• 제12C권5호
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• pp.633-642
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• 2005

유비쿼터스 컴퓨팅 시스템은 하나 이상의 컴퓨터가 네트워크로 상호 연결된 프로세서 시스템이다. 하지만, 기존의 보안 유지 방법은 정성적 탐지 및 대응책으로 공격이 발생한 이후 대응에만 치중하여 능동적 차원의 보안 유지 방법에 대한 연구가 부족하다. 따라서, 본 논문은 정량적인 분석을 통해 범용적 인프라의 개선뿐만 아니라 특정 인프라 공격에 대해서 탐지 및 데응할 수 있는 방법에 대해 제안한다. 이를 위해 시스템의 고정적 요소 정보, 임의의 요소 정보, 공격 유형 모델링을 근간으로 시스템의 보안성을 정량적으로 분석할 수 있도록 생존성에 대한 정의 및 모델링 기법을 사용하였다. 그리고 제안한 기법의 검증을 위해 TCP-SYN 공격과 Code-Red 웜 공격에 대한 생존성 분석을 수행하였다.

• 대한전기학회논문지:시스템및제어부문D
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• 제50권9호
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• pp.439-446
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• 2001

This paper considers the design technique of the real-time control algorithm to implement the electronic interlocking system which is the most important station control system in railway signal field. The proposed technique consists of the structure design and the detail design which are based on the ROOM(Real-Time Object-Oriented Modeling). The structure design is designed with a modeling using the heuristic search technique which, at first, catch and make out the specific requested condition, and then, is designed on the requested condition. The detail design can be implemented if it may get the satisfying values through the repetitive modeling after comparing and examining the data obtained from the structure design in order for the more reliable and accurate system to be implemented. The technique proposed in this paper is implemented with C++ language which is easy to be transferred and compatible with the existing interfaces, and also the operating system is designed and simulated on the VRTX which is a real-time operating system. This proposed technique is applied to the typical station model in order to prove the validity as verifying the performance of the modeled station.

• 산업기술연구
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• 제27권A호
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• pp.149-155
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• 2007

The counter emf(electromotive forces) of a permanent magnet multi-phase brushless motor is generally a non-sinusoidal wave or a non-ideal trapezoid. So, conventional modeling using a sinusoidal wave or an ideal trapezoid counter emf can result in errors. In order to reduce modeling errors for simulation and analysis the properties of a multi-phase brushless AC motor, this paper proposes a phase variable model that is a mixed modeling technique using both Finite Element Analysis(FEA) based circuits and motor voltage equations. The phase model parameters including the counter emf voltage waveform are obtained by using of FEA, and the mixed modeling technique based on circuits and equations is used to implement a simulation model for multi-phase brushless AC motors with any counter emf voltage waveforms. Adequacy of the proposed model is established from the simulation and experimental results for a seven-phase brushless motor.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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• pp.37-40
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• 2008

The purpose of this paper is to extract DEMs from Spot-3 strips using orbit modeling technique. Spot-3 stereo strip images along 420km in distance were used for experiments. The orbit modeling technique has been suggested to establish accurate geometric models for a whole strip taken on the same orbit using only a small number of GCPs on the top area of the strip. This method enables extraction of orientation parameters of the scene along the strip that is needed to generate DEMs. Consequently, we were able to extract DEMs over the areas without accurate GCPs obtained by GPS surveying per each scene. Assessment of accuracy was carried out using USGS DTED. DEMs generated from the orbit modelling technique suggested showed satisfactory performance when quantitative analysis of accuracy assessment was carried out.

• 한국컴퓨터그래픽스학회논문지
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• 제3권1호
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• pp.17-22
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• 1997

본 논문에서는 도로 환경을 재구성하기 위한 새로운 모델링 기법을 제시한다. 도로 환경 재구성을 위한 모델링 알고리즘은 도로 주변 건물들의 3차원 모델을 재구성하는 부분, 도로 모델을 편집 생성하는 부분, 그리고 기타 부가적인 객체들을 모델링하는 부분으로 나누어지는데, 각 부분은 모델링하는 대상의 특성에 따라 각기 다른 모델링 기법을 적용한다. 특히 도로 주변 건물의 3차원 모델을 재구성하기 위한 모델링 기법으로 여러 장의 사진으로부터 모델의 3차원 구조를 다면체 단위로 추출해내는 Photogrammetric Modeling 기법[1, 2]을 사용하였는데, 본 논문에서 제시하는 모델링 기법은 사용자 인터페이스를 개선하고 도로 환경이 지니는 제약조건들을 추가함으로써 도로라는 특수한 환경을 재구성하는데 있어 Photogrammetric Modeling기법에 비해 단순하고 용이한 시스템을 제공한다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.744-746
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• 2003

A 3D modeling of urban area can be composed the terrain modeling that can express specific and shape of the terrain and the object modeling such as buildings, trees and facilities which are found in urban areas. Especially in a 3D modeling of building, it is very important to make a unit model by simplifying 3D structure and to take a texture mapping, which can help visualize surface information. In this study, the texture mapping technique, based on library for 3D urban modeling, was used for building modeling. This technique applies the texture map in the form of library which is constructed as building types, and then take mapping to the 3D building frame. For effectively apply, this technique, we classified buildings automatically using LiDAR data and made 3D frame using LiDAR and digital map. To express the realistic building texture, we made the texture library using real building photograph.

• 대한전기학회논문지:전력기술부문A
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• 제52권3호
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• pp.179-182
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• 2003

Component-based method for load model not only should include the performances of the load components, but also should take into consideration the core losses of transformers, the line losses and the capacitor banks. Especially, capacitor bank affects the accuracy of reactive load model in load modeling. But it is difficult to identify actual reactive powers of capacitor banks in power system for load modeling. This research improves the component-based modeling method including uncertain capacitor bank. The proposed method is hybrid technique, which adds the measurement-based method to the existing component-based method for reliable information of capacitor band. The results of case studies were presented to verify the validity of the proposed method.

• 인터넷정보학회논문지
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• 제10권5호
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• pp.153-163
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• 2009

공급자 시스템이 제공하는 기능의 조합으로 새로운 서비스를 정의하기 위해서는 서비스 조합에 포함되는 기능, 즉 유스케이스가 명확히 식별되어야 한다. 그러나 현재의 유스케이스 모델링은 명세하고자 하는 목표 서브젝트의 외부 시스템을 액터로만 표현함으로써, 서비스 구성에 참여하는 외부 유스케이스를 명확하게 표현하지 못한다. 이러한 불명확성은 유스케이스 모델의 이해도를 저하시키는 원인이 되며, 목표 시스템이 참조하는 외부 시스템의 범위를 명확하게 한정하지 못하게 한다. 본 논문에서는 서비스 지향 컴퓨팅을 위한 확장 유스케이스 모델링 기법을 제시한다. 확장 모델링은 외부 서브젝트에 정의된 외부 유스케이스 및 컴포넌트를 목표 서브젝트 내에서 명시적으로 표현하도록 지원한다. 외부 유스케이스는 공급자 시스템에 정의된 기능을 표현하며, 목표 시스템이 참조하는 범위를 명확히 정의하는데 활용된다. 유스케이스 구현을 위한 외부 컴포넌트와의 관계성은 유스케이스 실체화를 통해 이루어진다. 유스케이스 모델의 확장은 UML 스테레오타입 확장 메커니즘을 이용한다. 따라서 기존 유스케이스 모델과의 호환성을 그대로 유지함으로써, 기존 유스케이스 모델링 기법과 일관되게 적용 가능하다.