• Journal of the Korea Safety Management & Science
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• v.3 no.1
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• pp.127-137
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• 2001

Because of the inherent flexibility in their design for improved material properties, composites have wide applications in aerospace vehicles and automobiles. The purpose of this study is to investigate the energy absorption characteristics of CFRf (Carbon Fiber Reinforced Plastics) tubes on static and impact tests. Static compression tests have been carried out using the static testing machine(Shin-gang buckling testing machine) and impact compression tests have been carried out using the vertical crushing testing machine. When such tubes were subjected to crushing loads, the response is complex and depends on the interaction between the different mechanisms that control the crushing process. The collapse characteristics and energy absorption were examined. Trigger and interlaminar number affect the energy absorption capability of CFRP tubes.

• Journal of the Korea Society for Simulation
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• v.27 no.1
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• pp.25-32
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• 2018

This paper presents an efficient software reliability testing method for the model based auto-generated code and reify a dynamic test procedure. The benefits of executing the model-based each static/dynamic reliability test before the code-based static/dynamic reliability test are described. Also, The correlations of code/model based reliability test are demonstrated by using model testing tool, Model Advisor and Verification and Validation, and the code testing tool, PolySpace and LDRA. The result of reliability test is indicated in this paper.

• The Journal of Korean Physical Therapy
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• v.29 no.3
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• pp.142-144
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• 2017

Purpose: Few studies have addressed the effect of diurnal circadian rhythms on postural stability, and thus the aim of the present study was to examine circadian effects on static and dynamic postural stability in young adults. Methods: Twenty-four subjects (9 men, 11 women: age=$22.20{\pm}1.77$, height=$167.20{\pm}10.47$, weight=$59.85{\pm}10.66$) from a university community volunteered for this study. Static and dynamic balance testing, which recorded using a Good Balance system (Good Balance, Metitur Ltd, Finland) was conducted at 9:00, 13:00, and 17:00 hours on two consecutive days, and the sequencing of static and dynamic balance tests were randomized. Results were analyzed using the non-parametric one-way repeated Friedman test in SPSS version 18.0 (SPSS Inc., Chicago, IL, USA), and variable found to be significant were subjected to Wilcoxon post hoc testing. Results: Static and dynamic balance showed significant difference at the three times assessments (test at 9:00, 13:00, and 17:00) during circadian. In the post hoc test of static (anteroposterior distance, mediolateral distance and COP (center of pressure) velocity) and dynamic balance (performance time), 13:00 was the longer and faster than 9:00. Conclusion: These results indicated that control of postural balance is influenced by diurnal circadian rhythms, and confirm that control of postural balance is more effective and better performance in the 09:00 hours than 13:00 hours or 17:00 hours.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.62 no.1
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• pp.30-35
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• 2013

Many function of railway signalling system which is in charge of most core function in a railway system are being operated by the software according to the development of computer technology. Accordingly, the source code testing to verify the safety of the railway signalling system software becomes to be more important, and related international standards highly recommend verifications on the source code also. For this reason, several related studies on vital source code verification were executed from several years ago in Korea. This paper performed tests through the application to railway signalling system being applied to the existing actual domestic railway sites through automated testing tools for coding rules of signalling system software and another signaling system software under development in Korea recently, and analyzed their results.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.12
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• pp.2945-2951
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• 2000

Because of the inherent flexibility in their design for improved material properties, composites have wide applications in aerospace vehicles and automobiles. The purpose of this study is to investigate the energy absorption characteristics of CFRP( Carbon Fiber Reinforced Plastics); tubes on static and impact tests. Static compression tests have been carried out using the static testing machine(Shin-gang buckling testing machine)and impact compression tests have been carried out using the vertival crushing testing machine. When such tubes were subjected to crushing loads, the response is complex and depends on the interaction between the different mechanisms that control the crushing process. The collapse characteristics and energy absorption were examined. Trigger and interlaminar number affect energy absorption capability of CFRP tubes.

• Wind and Structures
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• v.17 no.5
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• pp.495-513
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• 2013

Thin, high-strength steel roof cladding is widely used in residential and industrial low-rise buildings and is susceptible to failure during severe wind storms such as cyclones. Current cladding design is heavily reliant on experimental testing for the determination of roof cladding performance. Further study is necessary to evolve current design standards, and numerical modelling of roof cladding can provide an efficient and cost effective means of studying the response of cladding in great detail. This paper details the development of a numerical model that can simulate the static response of corrugated roof cladding. Finite element analysis (FEA) was utilised to determine the response of corrugated cladding subject to a static wind pressure, which included the anisotropic material properties and strain-hardening characteristics of the thin steel roof cladding. The model was then validated by comparing the numerical data with corresponding experimental test results. Based on this comparison, the model was found to successfully predict the fastener reaction, deflection and the characteristics in deformed shape of the cladding. The validated numerical model was then used to predict the response of the cladding subject to a design cyclone pressure trace, excluding fatigue effects, to demonstrate the potential of the model to investigate more complicated loading circumstances.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.317-325
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• 2011

Vehicle model validation for the static vehicle testing has been done by comparison of the simulation results and test results and the parameters of the vehicle model to be used in the simulation have been adjusted to reflect the measured behaviour. The vehicle model fort the simulation should be validated by suitable tests and/or practical experience. The static vehicle test used to validate the vehicle model are the weight measurement, the wheel offloading test, the bogie rotational resistance test and the sway test. Finally, the computer simulation model has been validated and using the validated vehicle model the acceptance of the vehicle safety of the resistance to flange climbing derailment at low speed can be examined.

• Proceedings of the KSR Conference
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• 2003.10a
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• pp.187-191
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• 2003

Aluminum carbody for rolling stocks is light and perfectly recycled, but includes severe defects which are very dangerous to fatigue strength. Static load test has been performed up to date to assess structural safety of the carbody. However, static load test is not sufficient to evaluate fatigue strength of the carbody, because fatigue failure is caused by dynamic load. In this study, the established load test methods for carbody are described and the characteristics of the methods are discussed. Also, a testing method to simulate dynamic loading condition is proposed for evaluation of fatigue strength of the carbody The results by the proposed testing method are compared with the results by the static load test and new findings are discussed.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.46-52
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• 2003

In this study, the full scale testing method of the geogrid-reiuorced soil Segmental Retaining Walll(SRW) under the simulated train loading were proposed in order to evaluate the applicability of reinforced soil SRW in railway embankment. The train loading was simulated by the design static wheel load and the impact coefficient due to the train passing velocity. This test was focused on the static performance of reinforced soil SRW in terms of the following measuring systems ; the horizontal earth pressure displacement acting on the facing block and the tensile strain along the geogrid. The data gathered from this full scale testing was compared with numerical analysis results by FLAC.

• Journal of the Korean Society for Railway
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• v.7 no.1
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• pp.32-36
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• 2004

Aluminum carbody for rolling stocks is light and perfectly recycled, but includes severe defects which are very dangerous to fatigue strength. Static load test has been performed up to date to assess structural safety of the carbody. However, static load test is not sufficient to evaluate fatigue strength of the carbody, because fatigue failure is caused by dynamic load. In this study, the established load test methods for carbody are described and the characteristics of the methods are discussed. Also, a testing method to simulate dynamic loading condition is proposed for evaluation of fatigue strength of the carbody. The results by the proposed testing method are compared with the results by the static load test and new findings are discussed.