• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2010년도 정기 학술대회
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• pp.268-271
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• 2010

In this paper, forward and reverse analysis is introduced in order to estimate the elastic-plastic properties from a power-law hardening bulk specimen materials with one simple spherical indentation impression test. In order to verify the reliability of the reverse analysis, we have simulated about a large range of materials that essentially cover all engineering materials, using ABAQUS(6.91) program. Then, we could obtained the fitting functions and plastic parameters from the numerical analysis results. Next, through the procedure of reverse analysis we can obtain the yield stress and power-law exponent. Finally, obtain good agreement between the result from reverse analysis and initial input data from experiment.

• 한국기계가공학회지
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• 제9권1호
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• pp.93-98
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• 2010

The metal fastening method is the new technology to repair cracks in the casting material using specially designed reverse screws. In this study, we conduct the finite element analysis to analyze the pulling force characteristic of a reverse screw, the core component of the metal fastening method, with respect to the change of the applying torque, frictional coefficient and front screw angle. The simplified analysis model with single screw pitch is proposed for convergency of the non-linear contact analysis. As a results, the pulling force of a reverse screw increase in proportion to the applying torque but exponentially decrease according to frictional coefficient. And also we can find the optimum front screw angle with the largest pulling force is $20^{\circ}$.

• 대한산업공학회지
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• 제40권2호
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• pp.205-214
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• 2014

As a result of the rapid economic growth and birth control policy, China is experiencing low fertility rates and increasing life expectancy, which makes Chinese population aging very quickly and unprepared for their retired life. The reverse mortgage may be an attractive option for the elderly because it is a loan against a house that they do not have to pay back as long as they live there. In this paper, in order to introduce the reverse mortgage scheme in China the factors that could influence the demand of reverse mortgage are reviewed and the Chinese market environment is analyzed. Then the principal component analysis is performed in order to recommend the regions or cities that have higher potential for successful implementation of a reverse mortgage than any other ones in China.

• International Journal of Naval Architecture and Ocean Engineering
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• 제6권1호
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• pp.60-73
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• 2014

The seaward reverse wave, occurring on the submerged dual porous horizontal plate, can contribute to the reduction of the transmitted wave as it reflects the propagating wave. However, the collision between the propagating and seaward reverse waves increases the water level and acts as a weight on the horizontal plate. This study investigated the characteristics of the wave pressure created by the seaward reverse wave through the analysis of experimental data. The analysis confirmed the following results: 1) the time series of the wave pressure showed reverse phase phenomena due to the collision, and the wave pressures acted simultaneously on both upper and lower surfaces of the horizontal plate; 2) the horizontal plate became repeatedly compressed and tensile before and after the occurrence of the seaward reverse wave; and 3) the seaward reverse wave created the total wave pressure to the maximum towards the direction of gravity, primarily on the upper plate. It was also confirmed that the wave distributions showed a similar trend to the wave steepness. Such outcome of the analysis will provide basic information to the structural analysis of the horizontal plate as a wave dissipater of the steel-type breakwater (STB).

• 한국생산제조학회지
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• 제20권4호
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• pp.464-471
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• 2011

We tried to analyze sound field of the interior of housing installed with an impeller using the Boundary Element Method (BEM) with the Kirchhoff-Helmholtz integral equation. In order to increase the accuracy of our analysis, reverse engineering technology, which has been developed in recent years. We measured and treated geometrical data with 3D scanning of the practical research object. After modeling by the reverse engineering, we analyzed variation of the BPF as adding vibration frequency and variation of the sound field of the interior of housing by changing the number of impeller blades. We also tried an analysis of free degree variation. Then, we proposed the analysis accuracy and noise reducing method by analysis result.

• 전력전자학회논문지
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• 제24권5호
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• pp.327-333
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• 2019

This study analyzes the reverse recovery phenomenon of a semi-bridgeless rectifier (SBR) in an inductive power transfer (IPT) system for electric vehicles. Ideally, the reverse recovery phenomenon does not occur in a diode rectifier, however, in practical systems, the reverse recovery phenomenon occurs even when the SBR operates like a diode rectifier due to high operating frequency. Therefore, a practical analysis of operation modes for SBRs is presented in this study, considering the reverse recovery phenomenon, and the requirements for SBR switches are proposed. The analysis results are experimentally verified using a 3.3 [kW] IPT system prototype to which three different types of switches are applied.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.920-924
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• 2002

This paper presents the reverse design of a cam mechanism using NURBS(Nonuniform Rational B-spline curve). Cam is very difficult to make the accurate shape on the design and the manufacture. Because the cam shape is commonly made in order to move in special functions. The reverse design can be used to check accuracy between the designed data and the manufactured data of the cam shape and also reproduce the cam without the design data. The reverse design procedures consist of motion analysis and curve fitting. The motion analysis is used the central difference method and the relative velocity method to find the displacement and velocity. The curve fitting is used NURBS to develope the whole curve. The central difference method is derived in the 3 dimensional space.

• 한국산업융합학회 논문집
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• 제26권6_2호
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• pp.1163-1169
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• 2023

In this study, the flow characteristics of the filter system were analyzed due to the effect of the density of the filter in the triple filter system. Flow analysis was performed as a flow passing through a porous medium. The flow characteristics of each filter system were analyzed by arranging filters with different densities in the forward flow flow and the reverse flow. The arrangement order of the triple filters was excellent in the case of forward fluid flow and in the case of higher density from the inside to the outside filter. In the reverse flow filter system, the performance of the system was the best in the case of reverse order filter arrangement. As a result of the analysis, Case II, which showed a pressure drop rate of 5.65% for forward flow, was the best in the reverse direction with a pressure drop rate of 14.25%. Considering reverse and forward flows, it was found that the optimal filter arrangement was most effective when the intermediate filter was the densest, and the inner or outer filter was less dense.

• 소성∙가공
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• 제10권4호
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• pp.329-337
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• 2001

The finite element simulation model and the program to calculate the reverse moment have been developed to analyse the stress state and deformation of pipe bending using local induction heating with small bending radius in this study. The reverse moment that is to be applied on the bending arm to control the wall thinning ratio of the bending outside to within a particular value. Even though the demand of pipes with small bending radius is increasing in power plants and ship buildings, the welded elbows are still widely used. The bending process with or without a reverse moment acting on the bending arm has been simulated. The reverse moments calculated from the developed program are in good agreement with the finite element simulations and the experiments.

• 대한토목학회논문집
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• 제37권2호
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• pp.437-444
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• 2017

본 연구의 목적은 고령층의 사회경제적 특성이 주택연금 이용 및 만족도에 영향을 미치는 요인을 실증분석하는 것이다. 2016년 주택연금 수요실태조사 자료를 바탕으로 이항로짓모형과 순서형로짓모형을 통한 실증분석을 실시하였다. 우선, 이항로짓모형을 활용하여 주택연금의 이용의 결정요인을 실증분석한 결과, 통계적으로 유의한 변수는 연령, 거주 지역, 보유자산, 가구원 수, 경제적으로 도움을 주고 있는 자녀의 유무로 나타났다. 구체적으로 연령이 높고, 수도권에 거주하며, 학력이 높을수록 주택연금의 이용 확률이 높아지는 것으로 추정되었다. 그리고 보유 자산이 작고, 가구원 수가 적으며, 경제적으로 도움을 주고 있는 자녀가 없는 경우에 주택연금의 이용 확률이 높아지는 것으로 추정되었다. 다음으로 순서형로짓모형을 활용하여 주택연금 이용 만족도를 실증분석한 결과, 통계적으로 유의한 변수는 연령, 성별, 거주 지역으로 추정되었다. 특히, 연령이 높고, 수도권에 거주하는 경우에는 주택연금 이용을 만족할 확률이 높아지는 것으로 추정되었다. 그리고 남성보다는 여성이 주택연금 이용에 만족할 확률이 높은 것으로 추정되었다. 실증분석 결과를 바탕으로 향후에 주택연금 가입률을 제고하고, 이용 만족도를 높이는 방안을 모색하는 것이 필요하다고 사료된다.