• Journal of the Earthquake Engineering Society of Korea
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• v.12 no.2
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• pp.1-8
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• 2008

Friction pendulum system is developed to prevent the damage of transformer, which is the most important among the electric power facilities, due to the earthquake and its seismic capacity is verified through the shaking table test. The applicability of friction pendulum system is confirmed as test results of compressive capacity test and friction test. Especially, as a result of shaking table test with a large scale transformer model, friction pendulum system gives to the reduction of maximum response acceleration by 30% at anchorage of transformer and 59% at the top of porcelain bushing comparing with the existing anchorage type. In addition to the reduction of maximum response acceleration, natural frequency of transformer is shifted to long period due to the friction pendulum system. In case that friction pendulum system is applied to the transformer, the damage of transformer can be prevented effectively under the earthquake.

• The Journal of the Convergence on Culture Technology
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• v.6 no.4
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• pp.703-708
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• 2020

As the risk of earthquakes increases recently, earthquake-resistant designs were getting interest. For this reason, this study applies that Friction pendulum-type seismic isolator is a device that attenuates seismic energy by friction and pendulum motion. The friction pendulum-type seismic isolator of this study is very easy to transport, install and maintain with light weight of metal by applying the slider using high strength engineering plastic. In addition, there is an advantage that the corrosion resistance is very excellent compared to the existing metal parts. However, there is concern about long-term durability by replacing metal materials. In this study, the frictional pendulum-type seismic isolator with EP was applied to compressive-shear test, repeated fatigue test, and ultimate load test after fatigue test, and analyzed the deformation and shear or properties after the test. As the results, the adequacy of long term fatigue durability was experimentally proven.

• Journal of Korean Society of Steel Construction
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• v.17 no.4 s.77
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• pp.407-417
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• 2005

An experimental and analytical study was performed to apply the friction pendulum system (FPS) to the main control room of a nuclear power plant. A friction pendulum bearing was fabricated, and the dynamic response of the bearing was evaluated. A partial model of a main control room attached to the FPS was tested on the shake table. The model consisted of a cabinet, a $3m\times3m$ access floor, and four friction pendulum bearings. The artificial time history based on the floor response spectrum of the main control room was used as the earthquake input signal in the test. Comparisons between the analytical study and the experimental study were conducted to verify the results and to extend the experimental study to the range of parameters that could not be experimentally studied.

• Journal of the Society of Naval Architects of Korea
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• v.32 no.3
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• pp.1-18
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• 1995

This paper deals with the vibration absorbers of gravitational and centrifugal pendulum types for vibration controls of ship's substructures such as radarmasts, bridgewings and funnels. The mathematical model of such a vibrating system with an absorber is described as a 2 degree of freedom system and an efficient formulation for optimum design of the absorber is presented. For investigation applicability of the two types of the absorbers to a structure system, numerical calculations and experiments hove been performed with variation of mass ratios for each type. According to the results of investigations, the vibration absorber of gravitational type proved to be more useful and efficient than one of centrifugal pendulum type in a view point of mass ratio.

• Journal of Acupuncture Research
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• v.22 no.6
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• pp.125-134
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• 2005

목적 : 이 연구의 목적은 플라시보 자락요법을 계발하기 위함이다. 방법 : 이 연구에서 우리는 자락요법을 잘 알고 있는 특정 피시험군에 진자락요법과 위자락요법을 시행하고, 피시험자에게 본인이 받은 치료가 무엇이었는지 설문조사하였다. 위자락요법은 피부를 뚫어 혈관을 자파시키지 않고 피부 겉에서 느낌만 나도록 자극을 주고 흡입하는 것이다. 결과 : 총 53명의 피시험자가 모든 시험과정에 적절하게 참가하였으므로 모든 데이터를 신뢰할 수 있었다. 결과는 두 그룹간에 유의한 차이를 발견할 수 없었다. 위자락요법을 받은 피시험자중 44.4%는 그들이 받은 치료가 진자락요법이라고 생각했고, 55.6%는 위자락요법이라고 생각했다. 진자락요법을 받은 피시험자중 53.8%는 그들이 받은 치료가 진자락요법이라고 생각했고, 46.2%는 위자락요법이라고 생각했다. 결론 : 각 군간의 민감도와 특이도 간에 유의한 차이가 나타나지 않으므로, 자락요법에 있어 플라시보가 성공했다고 볼 수 있다. 이 연구는 자락요법을 적응증으로 하는 다양한 질환의 임상연구에 있어서 대조군 처치시 좋은 모델을 제시하였다.

• Journal of Auto-vehicle Safety Association
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• v.6 no.1
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• pp.41-47
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• 2014

A new dummy has improved biofidelity from Fair to Good compare with EuroSID2re which is currently used for regulation tests and NCAP tests. Some instrumentation of each body region has been changed to measure the assessment of injury risk. The objective of this study is to find out the injury characteristic of each dummy and to calculate the relation between external force and injury for each dummy with pendulum tests. Finally, this study suggests the optimized external force to meet consumer tests. A new dummy named WorldSID for side impact will be introduced into EuroNCAP tests after 2015. Korea government is also planning to adopt WorldSID at KNCAP tests from 2017 and Global Technical Regulation (GTR) will also adopt WorldSID to oblique side pole crash.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.10a
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• pp.30-33
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• 2005

Although extruded aluminium bumper beam has been commonly used in advanced car makers, there are not so much precedent for it's localization. For the localization of aluminum bumper beam of 7XXX series, benchmarking, material modifications of 7XXX series aluminum alloy, section design of beam, impact analysis had been performed in this study. High fuel efficiency and weight reduction could be achieved by using aluminum bumper beam of which the weight is lighter than that of steel. Moreover, it is expected to reach higher recycling rate by substituting aluminum for steel.

• Proceedings of the Korean Nuclear Society Conference
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• 2002.05a
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• pp.210.1-210
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• 2002

• Review of KIISC
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• v.31 no.4
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• pp.67-75
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• 2021

지난 2020년 전 세계적으로 코로나 19 확진자가 급증하자 세계보건기구(WHO)는 코로나 19 대유행을 선언하였다. 이러한 질병의 확산을 막는 방안으로 다양한 시험들이 비대면 시험으로 전환되면서 부정행위에 대한 우려가 있다. 또한, 이러한 상황에서 비대면 시험을 진행하고자 할 때 참조할 만한 체계가 없는 것이 현실이다. 이러한 상황을 고려하여 감염병 확산 이후로 불가피하게 진행될 비대면 환경에서의 감독 및 시험 방식에 있어 4단계의 거버넌스를 제시하고자 한다. 해당 거버넌스는 시험에서 사용되는 활용도 및 빈도수와 시험 감독 강도에 따라 4단계로 정의된다. 각 단계의 거버넌스들은 기존의 비대면 시험 방식과 코로나 19 이후의 시험 방식에 대한 비교 및 조사와 여러 시험 형식의 특성을 고려하여 제시된다. 제시된 거버넌스는 비대면 시험을 준비하고 시행하는 기관, 기업 및 학교들의 참조 모델이 될 것으로 기대하며, 비대면 시험의 "효율성"과 "공정성"을 확보하는 데에 기여할 것을 기대한다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.28 no.4
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• pp.361-368
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• 2015

Recently, the earthquake has been increasing a lot, damage of electric power facility has been serious as well. Nowadays, the importance of pipe support system such as Hanger, Brace, Snubber connecting the main structure have been emphasized. These devices can prevent pipe from damage so that reduce the vibration and shock acting on the pipe. For this reason, the FCD(Friction Concave Damper) was developed and has been expected to reduce the vibration on the pipe through the Friction Pendulum System. This paper was described the introduction of self-developed mechanical damper using the friction pendulum principle and the characteristic test was performed to verify the performance of the device. Additionally the test results have been compared with predicted F.A.P(FCD Analysis Program-self developed) results. As a result, reliability of design could be improved.