• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.1240-1245
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• 2000

A Spacecraft container must afford the satellite a relatively benign thermal, vibration, and particle environment that is oblivious to the extreme temperatures, sand, dust, vibrations and shocks that can accompany the transportation. This paper discusses the extensive yet simple vibration test and validation of one such spacecraft container used for KOMPSA T-1 spacecraft, which was transported from KARl Taejon, Korea to Vandenberg Air Force Base(VAFB) on September 30 and launched successfully December 21, 1999. The test results are presented and compared with the design requirement. The dynamic characteristics of shipping container, such as natural frequencies, satisfied the design requirement and showed that shipping container was well. designed and manufactured. This kind of know-how will help to develop the next generation of Korean space program, such as KOMPSAT-2 and Korean tele-communication satellite.

• Journal of Mechanical Science and Technology
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• 제18권5호
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• pp.847-856
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• 2004

Heaters for the spacecraft propulsion system are sized to prevent propellant from catastrophic freezing. For this purpose, thermal mathematical model (TMM) of the propulsion system is developed. Calculation output is compared with the results obtained from thermal vacuum test in order to check the validity of TMM. Despite a little discrepancy between the two types of results, both of them are qualitatively compatible. It is concluded that the propulsion system heaters are correctly sized and TMM can be used as a thermal design tool for the spacecraft propulsion system.

• 한국소음진동공학회논문집
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• 제21권10호
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• pp.875-882
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• 2011

In this paper, the finite element analysis model of the mult-axial wheel durability test configuration is created using SAMCEF. Mooney-Rivlin 2nd model is applied to the tire model, and the variation of the air pressure inside the tire is considered. Vertical load, lateral load and camber angle are applied to the simulation model. The tire rotates because of the friction contact with a drum, and reaches its maximum speed of 60 km/h. The dynamics stress results of the simulation and experiment are compared, and the reliability of the simulation model is verified.

• 신재생에너지
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• 제4권3호
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• pp.51-57
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• 2008

The objective of this study is to develop and validate a compressed hydrogen storage system for fuel cell vehicles. The type3 composite cylinder consists of full wrapped composites on a seamless aluminum liner. The key technologies, including design, analysis, and optimized fabrication process for 350bar composite cylinder, were established and verified, and the facilities for fabrication and validation testing have been constructed. Prototype cylinders were fabricated and validated through burst test and ambient cycling test in accordance with international standard.

• 한국항만경제학회지
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• 제22권1호
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• pp.151-173
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• 2006

This paper aims to explore the strategic roles of information and strategic planning capabilities for firms' performance, and to examine the direct and indirect relationships between information capability, strategic planning capability, logistics performance and competitive advantage. The present research adopts resource based theory (RBT) to explore the relationships between a firm's specific capability and its performance and employs structural equation modelling (SEM) in order to test the validation of the measurement models and examine the relationships between construct variables. The current empirical test was conducted using the data collected from logistics managers of 101 Korean electronics companies. The empirical research presents positive influential relationships between (1) information/planning formality capability and strategic planning capability; (2) strategic planning capability and logistics performance; (3) logistics performance and competitive advantage; and (4) competitive advantage and competitive position in the market.

• 반도체디스플레이기술학회지
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• 제11권1호
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• pp.67-71
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• 2012

The optical properties of PDP, such as the transmittance and reflectance, were analyzed with 3D optical code. Three different ITO-less structures in the front panel are examined. In the assembled panel study, the test 1 structure shows 16.6% and 10.2% higher reflectance than the structures of tests 2 and 3, respectively. In order to check the validation of the simulation result, three 7.5-inch test panels having the same geometry and property are fabricated as simulation models. The calculated reflective properties are compared to the measured data from real panels. The relative difference extracted from the simulation and measurement methods is less than 4.9% and are well matched.

• International Journal of Aerospace System Engineering
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• 제5권1호
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• pp.9-18
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• 2018

The longitudinal flight parameters of a light airplane are estimated from flight test data by use of the output error method. The reliability of the flight test measurement is examined in engineering judgment, scatter and Cramer-Rao bound, which turns out to be satisfactory with minor defects. Estimated parameter values are validated by comparing the simulated responses with the ones from actual flight tests. The FTD(Flight Training Device) of a light airplane turns out to satisfy the qualification of FAA Level 5 FTD in longitudinal motion. All the necessary practices for generation of high-fidelity data in longitudinal motion of a light aircraft are successfully performed in this study.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1998년도 춘계학술발표회논문집(1)
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• pp.713-718
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• 1998

Henry-Fauske critical flow model was incorporated into TRAC-PF1 to correct some errors in the original TRAC-PFI critical flow model. Henry-Fouske mode1 was numerically implemented and tested against steady-state steam-water experimental data. The model was incorporated into TRAC-PFI and code assessment against Marviken Critical Flow Tests 15 and 24 was carried out. Calculations using RELAP5/MOD3 were also made for comparison. Ten cases were calculated each test and sensitivity study on nodalization as well as critical flow or model was performed Stand-alone numerical model test and code assessment were done for verification and validation of code modification. Calculation results show that the modified version of TRAC-PF1 has a capability to model critical flow correctly in various conditions.

• 한국농공학회지
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• 제42권3호
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• pp.97-106
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• 2000

The study is closely relevant to Lade's single work hardening model. This model has been shown to have good applicability to cohesive soils. However the validation of this model on the clayey soils has not been satisfactorily reported. To scrutinize the applicability of this model on clayey foundation the laboratory tests for Kwangyang clayey soils were performed using the improved cubical triaxial test apparatus designed originally by Lade. A computer program was developed by which soil parameters for the single work-hardening model can be rationally determined by deleting some dispersed test data generated usually at the initial stage of laboratory tests. And using the program numerical analysis of the cubical clayey specimens using intermediate principal stress was carried out and a good agreement between observed values and numerical results was found.

• 영어어문교육
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• 제7권2호
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• pp.17-36
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• 2002

This article begins by exploring recent developments in the use of the world wide webs in language testing about what a Web-based language test (WBT) is and how they are used in language testing. After a brief review of computer-based testing, WBTs are defined and categorized as low-tech or high tech. Since low-tech tests are the more feasible, they will constitute the focus of this paper. Next, item types for low-tech WBTs are described, and validation concerns that are specific to WBTs are discussed. After a brief overview of the combination of computer-adaptive and Web-based tests, the general advantages as well as design and implementation issues of WBTs are considered before examining the role that testing consequences play in deciding whether a WBT is an appropriate assessment instrument. It is argued that WBTs are most appropriate in low-stakes testing situations; but with proper supervision, they can also be used in medium-stakes situations although they are not generally recommended for high-stakes situations. Some possible ideas for future research are suggested.(169)