• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.117-120
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• 2007

The floor slabs of building structures are often subjected to the periodic force which is induced by vibrating machines or human activity(walking, jumping, running etc). These periodic forces cause excessive oscillation. In order to examine the dynamic characteristics of floor slabs, the dynamic characteristics test is accomplished. Generally, the Impact Hammer and Dynamic Exciter test is used to dynamic characteristics test. But the Impact Hammer test is not suitable to apply in building slabs. In this paper, It compared the performance of the Exciter and Impact Hammer test for dynamic characteristics analysis of floor slabs.

• 한국철도학회논문집
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• 제6권3호
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• pp.186-193
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• 2003

The object of this study is to ensure the stability of bulk cement cars conducting vibration performance test, dynamic characteristic analysis and static load test of bogie frame. In case of static load test, bogie static load test facility was used. In case of dynamic characteristic analysis, Vampire Software was used. In case of vibration performance test, real bulk cement cars were used in kyeung-bu line. In the results of static load test of bogie frame for bulk cement car, all structures satisfied allowable stress criteria of materials. The vibration performance test and dynamic characteristic analysis results satisfied allowable standards.

• 한국전문물리치료학회지
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• 제24권1호
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• pp.1-8
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• 2017

Background: The multiple hop test is an active performance test that has been commonly used to assess individuals with functional ankle instability. Previous studies have suggested that insufficiency of dynamic postural stability and passive stability during dynamic activities can have an influence on performance in the multiple hop test. However, no study has investigated the effects of dynamic postural stability training and ankle bracing on multiple hop test performance in individuals with functional ankle instability. Objects: The purpose of this study was to compare the immediate effects of dynamic postural stability training versus ankle bracing in the performance of the multiple hop test for participants with functional ankle instability. Methods: Twenty-nine participants with functional ankle instability who scored below 24 in the Cumberland Ankle Instability Tool were selected. The participants were randomly divided into two groups: a dynamic postural stability training group (n1=14) and an ankle bracing control group ($n_2=15$). The multiple hop tests were performed before and after applying each intervention. Dynamic postural stability training was performed using visual-feedback-based balance-training equipment; participants in this group were asked to perform a heel raise in a standing position while watching the centering of their forefoot pressure to prevent excessive ankle inversion. Ankle bracing was applied in the control group. Results: When comparing the pre- and post-intervention period for both groups, both methods significantly improved the results of the multiple hop test (p<.05). However, no significant differences were shown between the dynamic postural stability training and ankle bracing groups (p>.05). Conclusion: Both dynamic postural stability training and ankle bracing showed significant improvement (2.85 seconds and 2.05 seconds, respectively) in test performance. Further study is needed to determine the long-term effects of dynamic postural stability training and to determine whether insufficient dynamic postural stability is a causative factor for functional ankle instability.

• 정보처리학회논문지:소프트웨어 및 데이터공학
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• 제8권7호
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• pp.265-274
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• 2019

무기체계 소프트웨어 개발 시 수행하는 신뢰성 시험은 크게 정적 검증과 동적 검증으로 구분된다. 정적 검증에서는 소프트웨어 코드를 수행시키지 않고 코딩 규칙 점검, 취약점 점검, 소스 코드 메트릭 점검을 수행하고, 동적 검증에서는 요구 사항을 기반으로 실제 소프트웨어를 실행시켜 기능을 검증하고 코드 실행률을 측정한다. 이러한 정적/동적 검증의 목적은 소프트웨어에 존재하는 결함을 발견하기 위한 것이다. 그러나 현재의 무기체계 소프트웨어 신뢰성 시험만으로는 여전히 탐지할 수 없는 결함들이 존재한다. 본 논문에서는 소프트웨어에서 발생할 수 있는 결함에 대해 무기체계 신뢰성 시험의 정적 검증과 동적 검증으로 탐지를 할 수 있는지를 사례실험을 통하여 분석 한다. 그 결과로 현재의 정적 검증과 동적 코드 커버리지 측정에서 더 나아가 무기체계 신뢰성 시험, 특히 동적 시험의 개선방안으로 연결하고자 한다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.242-245
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• 2006

This paper is an assessment on the dynamic test results of optical bench for LEO satellite. According to the design requirements, optical bench was designed and manufactured. Dynamic test was performed to verify stability of optical bench. Low level random vibration test, sine burst test and sine vibration test are carried out to identify dynamic characteristics and to verify static strength and safety under quasi-static load conditions. From the result it can be stated that the optical bench is well qualified under the launch environmental conditions.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1533-1538
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• 2011

The dynamic characteristics such as resonant frequencies and dampings have been utilized as important parameters in dynamic behavior and inverse analyses. In general, the dynamic parameters have been determined based on design and experimental data, but experimental studies on the time-dependent changes of the dynamic parameters during service have rarely been conducted. Especially, unlike highway bridges, it is much easier for railroad bridges to estimate accumulated amount of fatigue because of the controlled train operation, and the study of dynamic characteristic change due to fatigue is useful, since it can enhance the accuracy of dynamic analysis. In this paper, the dynamic characteristic change due to fatigue is measured via the modal test on the PSC girder during a fatigue test. The test specimen utilized in the test is the IT girder which enhances the sectional capacity of the conventional PSC girders. The test specimen is designed 10m long and the modal tests are conducted during the application of fatigue load two million times. The test result shows that considerable changes in the measured dynamic parameters are observed as the fatigue accumulates, and these changes during the service life should be considered in designing railroad bridges.

• Structural Monitoring and Maintenance
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• 제11권3호
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• pp.173-185
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• 2024

Currently, the electro-hydraulic servo loading control system manufactured by MTS, OpenFresco hybrid test interface software and OpenSees finite element software are widely used in structure laboratories to carry out hybrid test, but there is no relevant public information about full structure pseudo-dynamic test based on the above software and hardware. In order to study the feasibility of using the above software and hardware to carry out full structure pseudo-dynamic test, the full structure pseudo-dynamic virtual experiments of a single degree of freedom (SDOF) structure and a two degrees of freedom (2DOFs) structure are carried out based on the MTS 793 Demo Mode, and the results are respectively compared with the finite element analysis method. The results show that the finite element analysis results and full structure pseudo-dynamic virtual experiment results are highly consistent, which verifies the feasibility of carrying out the full structure pseudo-dynamic test based on the above software and hardware. Then, a three story steel frame full structure pseudo-dynamic test is conducted, and the smooth implementation of full structure pseudo-dynamic test of the three story steel frame further verifies the reliability of thistesting method. The implementation method of carrying out the full structure pseudo-dynamic tests are introduced in detail, which can provide some reference for relevant research.

• 한국안광학회지
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• 제20권3호
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• pp.377-384
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• 2015

목적: 본 연구는 이간계인 하워드-돌먼 입체검사와 삼간계로 성인의 동적 입체시를 측정하여 비교해 보고, PD 및 굴절이상과 동적 입체시의 상관성을 분석해 보았다. 방법: 평균연령 $21.27{\pm}2.32$(19~32)세인 성인 93명(남자50, 여자43)을 대상으로 이간계(two-rods test)와 삼간계(three-rods test)로 검사거리 2.5 m에서 동적 입체시를 각각 5회 측정하였다. 결과: 이간계와 삼간계로 측정한 동적 입체시는 각각 전체 평균 $29.91{\pm}23.03$초, $23.75{\pm}21.65$초 였고, 이중 남자는 $28.36{\pm}22.38$초, $22.28{\pm}23.79$초 여자는 $31.71{\pm}23.91$초, $25.46{\pm}19.00$초로 이간계에 비해 삼간계로 측정한 동적 입체시가 모두 좋았으나 통계적으로 유의한 차이는 없었다(p>0.05). PD 평균 표준편차 범위 60.63 mm~66.19 mm 사이의 동적 입체시는 이간계 $31.48{\pm}24.87$초, 삼간계는 $22.54{\pm}17.22초$로 통계적으로 유의한 차이가 있었으나(p<0.05), 두 검사법의 동적 입체시와 PD의 상관성은 크지 않았다. 굴절이상을 기준으로 할 때도 이간계에 비해 삼간계로 측정한 동적입체시가 모두 더 좋게 나타났으나 통계적으로 유의한 차이는 없었고(p>0.05) 굴절이상과 두 동적 입체시간의 상관성도 거의 없었다. 두 입체시는 일반적으로 정상인의 동적 입체시로 간주하는 30~50초 범위에 해당하는 결과가 나타났다. 결론: 삼간계는 이간계보다 입체시가 더 낮게 나타나 동적 입체시의 더 낮은 최소 역치를 측정할 수 있고, 두 검사법이 성인의 동적 입체시 표준검사법으로 사용되고 동적 입체시의 기준을 적용하는데 유용할 것으로 사료된다. PD와 굴절이상은 동적 입체시에 큰 영향을 주지 않는 것으로 나타났다.

• 대한물리치료과학회지
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• 제29권1호
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• pp.73-86
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• 2022

Background: The purpose of this study is to investigate the effect of plantar flexor on muscle fatigue and endurance when two different sport tapes are applied. Design: Cross-sectional design. Methods: Fifty-one healthy adults were randomly assigned to dynamic taping group (n=17), kinesio taping group (n=17), and control group (n=17). The dynamic taping group used the dynamic tape. The kinesio tape group used the kinesio tape, and the control group doesn't used tape. Every group performed heel rise test and sEMG for every during pre-test and post-test. To evaluate plantar flexor endurance, the number of times was measured during the heel rise test. Results: The number of heel rises increased significantly in the post-test in dynamic taping group compared to the pre-test, and In comparison between groups, the number of heel rises significantly increased in dynamic taping group compared to kinesio taping group and control group. PEF value was significantly increased in the post-test compared to the pre-test in dynamic taping group, and there was a significant difference between the three groups according to the taping application. Conclusion: The results of this study confirmed that dynamic taping was effective in musclular fatigue and endurance on plantar flexor in healthy adults. Based on these results, it is suggested that the application of dynamic tape can be suggested as one of the intervention methods for muscle endurance and muscle fatigue.

• 한국지반환경공학회 논문집
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• 제18권9호
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• pp.19-31
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• 2017

미국 사례의 경우 항타말뚝과 현장타설말뚝은 동재하시험과 정재하시험 지지력 상관관계 분석에서 좋은 상관관계를 나타내었다. 하지만, 국내에서는 해외에서 많이 사용하지 않는 매입말뚝으로 주로 시공을 하고 있으며, 매입말뚝의 동재하시험 신뢰성에 대해 의문이 많아 동재하시험의 신뢰도를 확인하고자 하였다. 본 연구에서는 LH 현장(천안, 인천, 의정부)에서 PHC 매입말뚝에 대하여 재하시험을 실시하였으며, 동재하시험(EOID 7회, Restrike 7회)과 정재하시험(7회) 지지력을 비교 분석하였다. 그 결과 재항타동재하지지력 및 정재하지지력 평균 값 비교 시 정재하지지력 평균 값이 약 27% 높게 나타났다(신뢰도 : 0.73, 변동계수 : 0.3). 재항타지지력(Davisson 판정 값) 및 정재하지지력(Davisson 판정 값) 평균 값 비교 시 정재하지지력(Davisson 판정 값) 평균 값이 약 27% 높게 나타났다(신뢰도 : 0.73, 변동계수 : 0.2). 동재하시험과 정재하시험의 차이를 줄이고자 본 연구에서는 수정동재하지지력(EOID의 극한선단지지력+Restrike의 극한주면마찰력)을 제시하였으며, 수정동재하지지력과 정재하지지력을 비교했을 때는 그 차이가 9%로 줄어들었다(신뢰도 : 0.91, 변동계수 : 0.2). 또한 변동계수가 0.2로 줄어들어 일관성이 증가한 것으로 나타났다.