• Title/Summary/Keyword: two-way coincidence

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Verified 20-car Model of High-speed Train for Dynamic Response Analysis of Railway Bridges (검증된 고속철도 차량의 20량편성 정밀모형에 의한 철도교량의 동적응답 분석)

  • 김상효;김병석;허진영;최성락
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2001.10a
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    • pp.485-492
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    • 2001
  • The dynamic analysis model is developed with the high-speed train (KTX) and a 2-span continuous prestressed concrete box girder bridge with a double track. The analytical results are compared with the dynamic field test results and found to be valid to yield quite accurate dynamic responses. The various trainset models with different number of cars are developed and compared with the results of the regular 20-car trainset model. It is concluded that the reduced trainset models, such as 7-car and 10-car models, cannot exactly produce the dynamic responses of bridges, especially when the train speed is high. Under the coincidence condition of two trains traveling with resonance velocity in the opposite directions, it is found that the impact factor under two-way coincidence is three times larger than that under one-way traffic. Consequently, for the bridge with a double-track it is necessary to check not only the dynamic responses of the bridge with one-way traffic but those with two-way coincidence.

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Effects of Country-of-Origin Coincidence and Price Level on Fashion Products Evaluations - Moderating Effect of Gender - (원산지일치도와 가격수준에 따른 의류 제품평가 - 소비자 성별의 조절효과를 중심으로 -)

  • Kim, Yeon-Hee;Lee, Kyu-Hye
    • Journal of the Korean Society of Costume
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    • v.59 no.6
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    • pp.41-57
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    • 2009
  • Evaluations of fashion products are often influenced by consumers' knowledge of the country where the products were made in. As globalization progresses, country-of-origin information is widely regarded as a powerful cue on consumers' shopping behavior. The purpose of study was to examine the consumer evaluation of apparel products with uni-national or bi-national country of origin. The effect of price level and gender were also investigated. The empirical research design took 2${\times}$2 factorial design with the country-of-origin coincidence (uni-national vs. bi-national) and price (high vs. low) of gender (male vs. female). Consumers' ethnocentrism and country-of-origin interest were taken into account as covariates in the factorial design. The consumers' evaluation of fashion products was measured in terms of brand attitudes and product attitudes. Data from 514 respondents were analyzed with t-test, one-way ANOVA, two-way ANOVA, and ANCOVA. Results of this study affirmed the importance of price information rather than country-of-origin coincidence in brand attitudes and product attitudes. Only for male consumers, interaction effects of price and country-of-origin coincidence had significant eflects on utilitarian attitude. Effects of two covariate variables included in the study were significant for female respondents but not for male respondents.

Verified 20-car Model of High-speed Train for Dynamic Response Analysis of Railway Bridges (검증된 고속철도 차량의 20량편성 정밀모형에 의한 철도교량의 동적응답 분석)

  • 최성락;이용선;김상효;김병석
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.15 no.4
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    • pp.693-702
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    • 2002
  • The aim of this study is to develop a 3-dimensional dynamic analysis model, capable of considering the interaction between vehicles and bridges more accurately. The dynamic analysis model is developed with the high-speed train (KTX) and a 2-span continuous prestressed concrete box girder bridge with a double track. The 20-car model is developed using the moving vehicle model for the regular trainset. Three-dimensional frame elements are used for the bridge model. Using the developed models, a dynamic behavior analysis program is coded. The analytical results are compared with the dynamic field test results and found to be valid to yield quite accurate dynamic responses. Based on the results of this study, the hybrid model, made up of the moving vehicle model for the heaviest power car and the moving force model for the other cars, is quite simple and effective without loosing the accuracy that much. Under the coincidence condition of two trains traveling with resonance velocity in the opposite directions, it is necessary to check not only the dynamic responses of the bridge with one-way traffic but those with two- way coincidence.

Stereotactic Target Point Verification in Actual Treatment Position of Radiosurgery (방사선수술시 두개내 표적의 정위적좌표의 치료위치에서의 확인)

  • Yun, Hyong-Geun;Lee, Hyun-Koo
    • Radiation Oncology Journal
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    • v.13 no.4
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    • pp.403-409
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    • 1995
  • Purpose : Authors tried to enhance the safety and accuracy of radiosurgery by verifying stereotacitc target point in actual treatment position prior to irradiation. Materials and Methods : Before the actual treatment, several sections of anthropomorphic head phantom were used to create a condition of unknown coordinates of the target point. A film was sandwitched between the phantom sections and punctured by sharp needle tip. The tip of the needle represented the target point. The head phantom was fixed to the stereotactic ring and CT scan was done with CT localizer attached to the ring. After the CT scanning, the stereotactic coordinates of the target point were determined. The head phantom was secured to accelerator's treatment couch and the movement of laser isocenter to the stereotactic coordinates determined by CT scanning was performed using target positioner. Accelerator's anteroposterior and lateral portal films were taken using angiographic localizers. The stereotactic coordinates determined by analysis of portal films were compared with the stereotactic coordinates previously determined by CT scanning. Following the correction of discrepancy the head phantom was irradiated using a stereotactic technique of several arcs. After the irradiation, the film which was sandwitched between the phantom sections was developed and the degree of coincidence between the center of the radiation distribution with the target point represented by the hole in the film was measured. In the treatment of the actual patients, the way of determining the stereotactic coordinates with CT localizers and angiograuhic localizers was the same as the phantom study. After the correction of the discrepancy between two sets of coordinates, we proceeded to the irradiation of the actual patient. Results : In the phantom study, the agreement between the center of the radiation distribution and the localized target point was very good. By measuring optical density profiles of the sandwitched film along axes that intersected the target point, authors could confirm the discrepancy was 0.3 mm. In the treatment of an actual patient, the discrepancy between the stereotactic coordinates with CT localizers and angiographic localizers was 0.6 mm. Conclusion : By verifying stereotactic target point in actual treatment position prior to irradiation, the accuracy and safety of streotactic radiosurgery procedure were established.

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