• 한국전산유체공학회:학술대회논문집
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• 2009.11a
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• pp.77-83
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• 2009

In this study, we conducted resistance and propulsion performance test of ship composed of the Resistance Test, Propeller Open Water Test and Self Propulsion Test using the CFD(Computational Fluid Dynamics). We used commercial RANS(Reynolds Averaged Navier Stokes equation) solver, as a calculating tool. The unstructured grids were used in a bow and stern of ship, having complex shape, for a convenience of generating grids, and the structured grids were adopted in a central hull and rest of hull having a relatively simple shape which is called hybrid grid method. In addition, The sliding mesh method was adopted to rotate a propeller directly in the Propeller Open Water and Self Propulsion Test. The Resistance Test and Self Propulsion Test were calculated using Volume of Fluid (VOF) model and considering a free surface. And all The three cases were applied realizable k-epsilon model as the turbulence model. The results of calculations were verified for the suitability of calculations by comparing MOERI's EFD results.

• The Mathematical Education
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• v.42 no.2
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• pp.159-176
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• 2003

From the mid-1990s in Korea, performance assessment has been continuously emphasized in school mathematics and thus many researchers and teachers have been steadily studying this topic. But the concepts relevant to performance assessment and its purposes are very confusing because the mathematics educators' different views and voices are vary. As a result most mathematics teachers experience trouble in executing performance assessment properly and effectively in their math class. This unability for proper execution of performance assessment was once again revealed in this study which dealt with 15 articles on performance assessment. These 15 articles includes almost every article written on the topic of performance assessment that have been published in 4 domestic journals since December 1997. By examining this inability, it is required that its concepts and purposes should be organized with a common view and newly defined in the near future. Therefore, to successfully accomplish this, this paper outlines the basic problems on the understanding of performance assessment as follows: ㆍWhat is the relationship between performance assessment and alternative assessment\ulcorner ㆍWhat is the proper types(methods) of performance assessment\ulcorner ㆍIs the subject test a type of performance assessment\ulcorner ㆍWhat is the difference between subject test and essay test\ulcorner ㆍWhat is the relationship between performance assessment and performance tasks\ulcorner ㆍWhat is the relationship between performance tests and project method\ulcorner ㆍWhat is a project method\ulcorner ㆍIs it assessment standard or scoring standard to score a test result\ulcorner ㆍWhat is the difference between analytic scoring method and holistic scoring method?

• Tribology and Lubricants
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• v.25 no.3
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• pp.187-191
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• 2009

A leakage performance test and an endurance performance test of a 75 ton class turbopump mechanical face seal are performed using water under high speed and high temperature environment. A prototype mechanical face seal is manufactured for the purpose of sealing of fuel between a fuel pump and turbine. By simulating operating condition experimentally, the leakage rate and seal carbon wear rate are obtained to evaluate the performance of the prototype mechanical face seal. The test results show the acceptable leakage performance and reasonable wear tendency as well.

• Journal of the Semiconductor & Display Technology
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• v.11 no.2
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• pp.59-62
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• 2012

This test method covers a procedure for measuring particle removal characteristic of equipment fan filter unit(EFFU) installed inside of semiconductor process equipments, FPD manufacturing equipments and so on. Since EFFU is a combination of air filter and the assembly of fan, motor and frame, the integrity of these parts is very important for the performance of EFFU. So a conventional particle removal test method for air filters is not suitable for EFFU particle removal performance. This test method defines an evaluation method for EFFU which is installed inside an enclosed space to remove particles that are generated inside process equipment. The particle removal performance of EFFUs is usually depending on the performance of filter media and air flow rate. To understand a performance of an EFFU, the filter media characteristic, air flow rate and the integrity of EFFU parts should be considered simultaneously. This test method is intended to demonstrate the system performance of an EFFU and successfully evaluated EFFU performance characteristics.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2005.11a
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• pp.33-38
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• 2005

In this paper, a simulator for radar performance evaluation in a far-field test range is proposed, which can forecast maximum detection range, minimum detection range, number of test trials, resolution (range, azimuth, elevation) with input parameters before radar performance test and process results after. The proposed simulator is designed by Microsoft Foundation Class (MFC) of VC++ 6.0.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.4
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• pp.68-75
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• 2018

This study presents the performance test results and the analyses of the vitiated air heater with high temperature and high pressure. In the performance test, four test conditions and three rake measurement conditions were implemented. In the results of the performance test, the vitiated air heater met targets of temperature and flow rate, and the performance with maximum temperature of 2000 K and maximum combustion pressure of 40 bar was confirmed. Flow rate of provided methane increased 36% more than what was calculated, and 19.6% difference was displayed between measured temperature and theoretically calculated temperature.

• Journal of Digital Contents Society
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• v.19 no.4
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• pp.801-808
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• 2018

The performance test methodology for switch, router or integrated networks that make up the wired network is not clearly defined. Due to smart phones and multimedia traffic, the speed of the network is rapidly increasing to 100Gbps. However, there is no formalized test method, and performance test related parts are still being tested based on old data. Telecommunication companies and companies are testing their requirements in their own BMT, and government or public institutions are requesting performance tests from external organizations. As the demand for the performance test of next generation network equipments and the integrated network increases, analysis of the performance test method should be done as soon as possible. Therefore, in this paper, we analyze the performance test method performed by the institute and propose guidelines that can be applied to all wired network equipment.

• The Journal of Korean Physical Therapy
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• v.28 no.4
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• pp.254-258
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• 2016

Purpose: This study was conducted to identify the effects of dual task training on balance and functional performance in high school soccer players with functional ankle instability. Methods: Twenty high school soccer players with functional ankle instability were randomly assigned to a single task training group and a dual task training group. One participant who did not participate regularly in the training was excluded. The single task training group (n=9) received balance training on an unstable surface. The dual task training group (n=10) received balance training on an unstable surface and had to catch thrown balls during the balance training. Both groups were trained for 4 weeks, 3 days a week. The balance and functional performance of both groups was measured before and after training. Balance was measured using an anterior-posterior and medio-lateral balance. Functional performance was measured based on a figure-of-8 hop test, up-down hop test, and a single hop test. All data were analyzed by repeated two-way ANOVA tests. Results: A time by group interaction effect was not observed in the medio-lateral balance test, figure-of-8 hop test, or single hop test (p>0.05). A time by group interaction effect was observed in the anterior-posterior balance and up-down hop test (p<0.05). Conclusion: These results suggest that dual task training improved balance and functional performance better than single task training for some items.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.6
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• pp.1138-1143
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• 2011

One of the critical items in radar testing is the ability to evaluate the performance of radar systems under real operational environments. But it takes lots of time and cost to operate real targets and analyze the test results due to a large amount of data based on these complicated environments. In this paper, the Radar Simulative T&E Lab. is introduced, and the test and analysis results of the developing radar for predicting the radar system performance are described in the Radar Simulative T&E Lab. This laboratory could be used to test the far-field characteristics of antenna radiation pattern and to perform an effective radar system test and evaluation using a simulative target generator under a low cost repeating test situation.

• Proceedings of the KSR Conference
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• 2003.05a
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• pp.700-705
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• 2003

The object of this study is to ensure the stability of flat freight cars using vibration performance test and static load test of body structures. We examined the flat car though static load test and dynamic characteristics analysis related traveling stability and vibration performance. In the results of static load test of body structures for flat car, all structures satisfied allowable stress of materials. The vibration performance test was satisfied with allowable standards. Although flat car exceed speed a little at some speed interval, it was estimated that the cause was not cars but rail.