• 제목/요약/키워드: Impact Analyses

검색결과 1,408건 처리시간 0.032초

충격해석을 위한 새로운 불연속 시간적분법의 개발 (Development of a New Discontinuous Time Integration Method for Transient Analysis of Impact Phenomena)

  • 조진연;김승조
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 1998년도 춘계학술대회논문집; 용평리조트 타워콘도, 21-22 May 1998
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    • pp.407-412
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    • 1998
  • In this work, a new time integration method is proposed using the generalized derivative concept to simulate the dynamic phenomena having sudden constraint occurring in dynamic contact/impact problems. By the adoption of the generalized derivative concept and jump assumption, discontinuity can be incorporated in time integration and as a result, the algorithm does not need any other special consideration of jumps in dynamic field variables due to sudden constraint like dynamic contact-release conditions. To observe the characteristics of the proposed time integration method, the stability and convergence analyses are carried out. In numerical tests, several dynamic contact/impact problems are analyzed by straightforward application of the proposed time integration method with the exterior penalty method.

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퇴직한 남편과 그 부인의 탄력성과 적응분석 (Resilience and Adjustment of Retired Husbands and Wives)

  • 김명자
    • 가정과삶의질연구
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    • 제21권6호
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    • pp.117-127
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    • 2003
  • This study examined the effect of resilience on the adjustment of retired husbands and their wives. Data was collected from 174 retired husbands and their wives in the Seoul metropolitan area. Collected data were analyzed by mean score, percentile, paired-t tests and regression analyses. The major findings were as follows : 1. There was no significant difference in the adjustments between retired husbands and their wives. 2. Individual resilience, family resilience and social resilience had a strong impact on the adjustment of retired husbands and their wives. Self-esteem, acceptance of retirement, communication between the couple, family cohesion, and retirement policy had a significantly positive impact on the husbands' adjustment. 3. As for the adjustment of the wives, self-esteem, communication between the couple, family cohesion, acceptance of husbands' retirement and religious activity had a significantly positive impact. In summary, this study shows the importance of resilience in the adjustment of retired husbands and their wives.

FRP Sheet로 보강된 콘크리트의 저속 충격 저항 성능에 대한 해석적 평가 (Analytical Study on Concrete Strengthened with FRP Sheet under Low-velocity Impact Loading)

  • 김윤지;류두열;이슬기;김미혜;윤영수
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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    • pp.159-160
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    • 2010
  • FRP는 상대적으로 높은 인성으로 인해 충격하중이나 폭발하중과 같은 극한 하중으로 문제가 발생하는 구조물에 적용할 수 있다. 충격 저항성능을 향상시키고자 FRP sheet를 사용하여 인장부를 보강한 콘크리트 부재의 유한요소 해석을 수행하였다.

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응력파를 이용한 비파괴 탐상기법의 수치해석 적용성에 관한 연구 (A Study on Applicability of Numerical Analyses for Stress Wave-Based NDE Techniques)

  • 이영준;이종세
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2003년도 봄 학술발표회 논문집
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    • pp.504-512
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    • 2003
  • Simulation programs have been developed and used as an attempt to improve the accuracy of Non-Destructive Evaluation(NDE) techniques. The applicability of these programs is very limited, however, because it is difficult to describe the delicacy of the propagation of stress waves. To investigate the applicability of the finite element analysis for stress wave-based NDE techniques numerical simulation for Impact-Echo method and SASW method is performed. The numerical studies are performed to determine the essential parameters such as contact time of impact load, mesh size and time step size. These studies show that the choice of parameter is very important for improving the accuracy and confidence of the numerical procedure and, thereby, the applicability of the numerical analysis for stress wave-based NDE techniques

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중소기업의 산업환경, 기술협력 및 성과간의 구조적 관계에 관한 연구 (A Study on Structural Relationship among Industrial Environment, Technological Cooperation and Performance of Small and Medium-sized Firms)

  • 나상균
    • 대한안전경영과학회지
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    • 제11권2호
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    • pp.223-233
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    • 2009
  • This study was aimed at analyzing the structural relationship among such factors as industrial environment, technological cooperation, technological innovation performance and management performance that are essential to technological innovation of small and medium-sized companies. For this aim, an analysis was conducted to determine which of the factors in industrial environment has impact on technological cooperation of small and medium-sized companies. An empirical analysis was also performance to find what kind of effects the technological cooperation may have on technological innovation and management performance. From the analyses, it became known that: first, changes in industrial environment have influence on technical cooperation factors including production technology, technical information, technical manpower and fund for technology that are assorted by means of factorial analysis; second, the technological cooperation of small and medium-sized companies has impact on their technological innovation performance; and third, the technological cooperation of small and medium-sized companies has impact on management performance.

고속충격시 볼탄에 의한 알루미늄 합금의 관통 깊이와 형상에 관한 실험적 연구 (The experimental investigation for penetration depth and shape of aluminum alloy plates by 5.56mm ball projectile with striking velocities between 350 and 750㎧)

  • 손세원;김희재;김영태
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 추계학술대회 논문집
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    • pp.800-803
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    • 2002
  • This investigation describes and analyses the experimental results proper to the penetration of Al5052-H34 alloy plates of thickness 6, 12 and 16mm(T/D=1, 2, 3) by 5.56mm ball projectiles over the velocity range 350-750㎧. All the high velocity impact tests were carried out at normal impact angle, i.e. zero obliquity. The experimental results presented the variation of depth of penetration, bulge height and diameter, plugged length and diameter with the velocity fur tests on each plate of a given thickness in order to determine the deformation shapes of 5.56mm ball projectiles and targets. Also the protection ballistic limit($V_50$) tests were conducted.

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Market, Firm, and Project-level Effects on the Innovation Impact of FP RTD Projects

  • Vonortas, Nicholas S.
    • STI Policy Review
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    • 제1권2호
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    • pp.69-88
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    • 2010
  • This paper explores the determinants of the innovation impact of publicly funded R&D projects along three broad dimensions, namely project, firm and market-related factors. In addition to these factors we examine the attributes of the research result per se and aspects of the commercialization process. The observations from empirical and qualitative analyses are based on R&D projects funded by the Fifth and Sixth Research Framework Programmes of the European Union. Firm size, prior experience, innovation culture, the nature of the project itself, explicit intension to commercialize, consortium management and strategy are the factors with the strongest effect on project success, defined in terms of product/process innovation and/or technical knowledge creation. The paper provides important implications for the organization, objectives, and management of public programmes that fund R&D and for project and participant selection.

국가이미지와 기업브랜드이미지가 제품이미지 및 구매의도에 미치는 영향에 대한 연구 -한.중 교역을 중심으로- (A Study on the Impact of National Image and Corporation Brand Image on Product Image and Customer's Purchasing Intention)

  • 홍상진
    • 대한안전경영과학회지
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    • 제13권3호
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    • pp.169-174
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    • 2011
  • The purpose of this study was to clarify the impact of national and corporate brand image of Korea on chinese consumers' purchasing Intention, also the impact of China on korean consumers' purchasing Intention. And the second aim of the research is to provide Korean businessmen who are interested in chinese market with information about chinese consumers' purchasing behaviour. Data from 205 chinese and korean consumers were analysed. As the result of analyses, it was found that Korean country image positive affects corporate brand image(samsung) and Chinese country image negative affects corporate brand image(haier) and product image. Korean corporate brand image only affects product image on chinese consumers. The product image affects Korean and Chinese consumer's purchasing intention.

시간 주파수 분석을 이용한 충격발생 위치 추정 (Source Localization of an Impact on a Plate using Time-Frequency Analysis)

  • 박진호;최영철;이정한
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 추계학술대회논문집
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    • pp.107-111
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    • 2005
  • It has been reviewed whether it would be suitable that the application of the time-frequency signal analysis techniques to estimate the location of the impact source in plate structure. The STFT(Short Time Fourier Transform), WVD(Wigner-Ville distribution) and CWT(Continuous Wavelet Transform) methods are introduced and the advantages and disadvantages of those methods are described by using a simulated signal component. The essential of the above proposed techniques is to separate the traveling waves in both time and frequency domains using the dispersion characteristics of the structural waves. These time-frequency methods are expected to be more useful than the conventional time domain analyses fer the impact localization problem on a plate type structure. Also it has been concluded that the smoothed WVD can give more reliable means than the other methodologies for the location estimation in a noisy environment.

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The Impact of Knowledge Management on Organizational Performance by Considering Structure and Culture in Vietnam

  • HUYNH, Quang Linh
    • The Journal of Asian Finance, Economics and Business
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    • 제9권10호
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    • pp.97-104
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    • 2022
  • The purpose of the existing work is to inspect the impact of knowledge management on organizational performance. Business experts now appreciate how important knowledge management is for organizational performance. Earlier studies have investigated the research model with causal linkages, however, only a few of them have considered sample-selecting bias problems when analyzing the model of knowledge management on organizational performance. The number of 312 executives related to knowledge management from 312 enterprises that have been approved with quality management systems offered suitable responses for analyses. The data was employed to investigate the effect of knowledge management on organizational performance, considering sample-selecting bias. The empirical outcomes indicate that sample-selecting bias exists in the causal impact of knowledge management on organizational performance. The empirical findings are helpful to scholars of knowledge management as well as business executives by giving an insight into the casual effect of knowledge management on organizational performance with the intervention of sample-selecting bias. The acceptance of knowledge management should be tailored to improve competitive advantages that will lead to better organizational performance.