• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2003년도 봄 학술발표회 논문집
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• pp.77-84
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• 2003

In this paper, the refined plastic-hinge analysis accounting for the effect of strain reversal caused by non-proportional loading is developed. This analysis accounts for material and geometric nonlinearities of the structural system and its component members. Moreover, the problem, conventional refined plastic-hinge analyses have underestimated the strength of structures subjected to non-proportional loading, is overcome. The modified stiffness degradation model approximating the effect of strain reversal is discussed in detail. The proposed analysis is verified by the comparison of the finite element analysis. A case study shows that the effect of strain reversal is a very crucial element to be considered in second-order plastic-hinge analysis. The proposed analysis is shown to be an efficient, reliable tool ready to be implemented into design practice.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.395-403
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• 2007

Railroad track consists of relatively simple structures such as rail, sleeper, ballast. Roadbed shares vertical pressure by train load which passed through rail to ballast as base that supports the track. For evaluating stress and displacement of roadbed due to the railroad load is an important role on the track as a basic data for estimation of the durability and design of the roadbed thickness. GEOTRACK program applied multi-layered theory was developed for analyzing railroad track structure. GEOTRACK program is a sort of numerical analysis program which has advantage that can analysis component of track by simple method. In this study, this program was used to preform the numerical analysis by changing track conditions and roadbed conditions such as tie, reinforced roadbed, dynamic wheel load, Resilient modulus and so on. Further detail will be presented on the paper.

• 한국정밀공학회지
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• 제14권8호
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• pp.115-121
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• 1997

The in-process detection of the tool wear is one of the most important technologies in completely auto- matic operation of machine tool. In this research, using the tools having flank wear, the dynamic compo- nent of cutting forces is considered to be available for identifying the cutting process. In order to investi- gate this relation in detail, the cutting forces in turning of workpiece made of aluminum were measured by dynamometer of piezoelectric type, and the dynamic components of cutting force were analyzed. The fre- quency analysis, probability density analysis and RMS analysis of the dynamic components were carried out independently. Through the experiments, the characteristics of the tool system have a large effect on the dynamic component of cutting forces. As a result, it is shown that the dynamic cutting force was able to detect flank wear accurately.

• 응용통계연구
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• 제23권5호
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• pp.813-822
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• 2010

차원 축소(dimension reduction) 기법은 주로 횡단면 자료 분석에서 널리 이용되어 왔으며 시계열 분석 분야에서의 적용은 상대적으로 미진한 실정이다. 본 논문에서는 부분-수량화를 통한 주성분분석 방법을 계절형 시계열에 적용시켜 시계열 자료의 차원 축소를 시도하고자 한다. 분석 방법론을 단계별로 제시하였으며 월별 실업률 자료 분석을 통해 설명하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2008년도 제39회 하계학술대회
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• pp.1014-1015
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• 2008

Safety critical systems are those in which a failure can have serious and irreversible consequences. Nowadays digital technology has been rapidly applied to critical system such as railways, airplanes, nuclear power plants, and vehicles. The main difference between analog system and digital system is that the software is the key component of the digital system. The digital system performs more varying and highly complex functions efficiently compared to the existing analog system because software can be flexibly designed and implemented. The flexible design make it difficult to predict the software failures. This paper reviews safety standard and criteria for safety critical system such as railway system and suggests development process, ordering management and assessment process for railway software with more detail description.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2010년도 한국컴퓨터종합학술대회논문집 Vol.37 No.1(D)
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• pp.190-195
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• 2010

Vehicular ad hoc networks (VANETs) have a number of interesting applications to preserve road safety, notify users about changed road/traffic condition, handling post accident hazards and moreover service oriented applications to make the travel convenient to the drivers. Use of common information format for diverse applications enables the application developers to easily design flexible information dissemination system for new applications or add new features to existing application. This paper introduces a common information format for various applications in VANETs. The main goal of the paper is to design generalized distributed architectures for vehicular networks, which considers diverse application development scenarios and uses common information format. The proposed architectures enable the application developers to flexibly disseminate information to affected or interested user. In this paper, we have given a detail description of each component of the architectures and how they communicate with each other. In future, we will implement the proposed architecture using suitable simulator.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.292-295
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• 2006

Dimension and capacity of the zero tail type mini excavator are small as compared with medium or large excavators. Therefore, problems of the noise and the heat are major issues in design due to layout of each component such as the engine and the hydraulic module. It is necessary to reduce the noise and the vibration of construction machine, due to be enforced regulation for high noise construction machinery in the world. The objective of this study is to provide basic data which is apply to predict noise effect in detail design stage by estimating noise of cabin for zero tail type mini excavator.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2008년도 춘계학술발표대회 논문집
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• pp.241-244
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• 2008

This study focused on the checking of design guideline using concept of reference plane as a promoting tool in order to apply to practical affair in relation to material standardization in housing build. For this purpose, we above all defined the role of reference plane. After establishing structural type can correspond to planning module of building components and coordination condition, we did exemplicated the sub-detail of building components which be to detach according to design method using the concept of reference plane that be complexed with spacial territory and replace cycle of building component or material.

• 대한전기학회논문지:시스템및제어부문D
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• 제54권3호
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• pp.194-197
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• 2005

Digital display products are gradually becoming diversified and pursuing high-quality image display. Digital TV supports various video signal formats from conventional SD to digital HD because the format conversion of video image is required. Traditional format conversion of the video image is achieved by a 1-dimensional linear interpolator applying both horizontal and vertical direction. Jagging artifact can be expressed as the linkage of line segments in several directions. In this paper, we present the method that removes jagging artifact effectively using PCA (Principle Component Analysis) and reserve the detail in a given image.

• Nuclear Engineering and Technology
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• 제30권4호
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• pp.328-341
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• 1998

This paper presents in detail the hydraulic characteristic measurements using LDV(Laser Doppler Velocimetry) in subchannels of a HANARO, KAERI research reactor, fuel bundle. The fuel bundle consists of 18 axially finned rods with 3 spacer grids and has a cylindrical configuration. Axial velocity and turbulent intensity were measured. The effects of the spacer grids on the turbulent flow were investigated using the experimental results. Pressure drops for each component of the fuel bundle were measured, and the friction factors of the fuel bundle and the loss coefficients for the spacer grids were estimated from the measured pressure drops. The turbulent thermal mixing phenomena were discussed.