• The KSFM Journal of Fluid Machinery
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• v.5 no.1 s.14
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• pp.27-32
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• 2002

The turbopump inducer cavitation is very important for the success of a liquid rocket engine. In this study, the performance test and cavitation performance test were carried out at various rotational speeds with two inducers of different diameter. The rotational speed was varied by 4000, 6000, and 8000 rpm, and the size effect was tested for the normal inducer and twice-enlarged one. The hydraulic performance results showed that the similarity was satisfied over the entire test range of the present study. The blade thickness effect was examined and showed that the increased blade thickness resulted in decreased efficiency and worse cavitation performance for the large tip clearance. The cavitation performance test results showed that the breakdown NPSH increased as the flow coefficient, and was not affected by the rotational speed.

• 유체기계공업학회:학술대회논문집
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• 2001.11a
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• pp.229-234
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• 2001

The turbopump inducer cavitation is very important for the success of a Liquid rocket engine. In this study the performance test and cavitation performance test were carried out at various rotational speed with two different diameter inducers. The rotational speed were varied 4000, 6000, 8000 rpm and the variation to the diameter of an inducer were taken as design size and 2 times enlarged size. The major results of the present study were as follows. 1. The hydraulic performance results showed that the similarity was met over the entire test range of the present study. 2. The blade thickness effect was examined and showed that the increased blade thickness resulted in decreased efficiency and worse cavitation performance for large tip clearance. 3. The cavitation performance test results showed that the breakdown NPSH increases as the flow coefficient and does not affected by the rotational speed.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.30 no.5
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• pp.62-70
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• 2002

Methodology of predicting steady performance of gas turbine engine from transient test data was explored to develop an economic performance test technique. Discrepancy of transient performance from steady performance was categorized as dynamic, thermal and aerodynamic transient effects. Each effect was mathematically modeled and quantified to provide correction factors for calculating steady performance. Engine performance tests were conducted at Altitude Engine Test Facility of KARI. The influence of engine inlet/outlet condition change on engine performance was corrected firstly, and then steady performance was predicted from the correction factors. The result was compared with steady performance test data. This correction method showed an acceptable level of precision, 3.68% difference of fuel flow.

• Journal of The Korean Society of Integrative Medicine
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• v.10 no.2
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• pp.27-35
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• 2022

Purpose : The purpose of this study is to analyze the correlation between the TPI Level 1 test and the performance of KPGA professional golf players. Methods : In 2019, 30 KPGA golf players attempted in the TPI Level 1 test. Their performance was then compared with the test based on the players' aggregated official records on the KPGA website, The most meaningful prize money ranking, average driving distance, fairway landing rate, and average number of putts were considered to evaluate their performance. Additionally, to obtain the average value of the players' accumulated records, the period from the first game in March 2019 to the end of October was considered. Results : The criterion for the difference between the upper group and the lower group was set based on the 9 points of the TPI Level 1 test, which showed the most significant difference. The prize money ranking stood at 63.00±51.77 in the upper group and 113.92±68.79 in the lower group in the TPI Level 1 test, the difference was significantly higher (p<.05) for the upper group (p<.05). The average driving distance was 286.15±10.06 yds for the upper group and 277.39±8.49 yds for the lower group, group, with the driving distance significantly higher in the upper group (p<.05). Further, the average number of putts for the upper group was 1.81±.02 and 1.85±.04 for the lower group, indicating a significant difference. Conclusion : A higher TPI Level 1 test score is likely to have a positive effect on performance.. As a result of the statistical values of this study, it was found that players must possess at least 9 out of 17 types of physical abilities Therefore, it can be considered that training and intervention to acquire these physical abilities are essential.

• Journal of the Korean Solar Energy Society
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• v.27 no.1
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• pp.39-45
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• 2007

In this paper, we analyzed the elements of measurement uncertainty on electrical performance test which are the most important things in photovoltaic module performance test. Repeating the performance test by 6 men, the measurement uncertainty could be calculated. In this experiment, Solar Simulator (A-Class pulse type) used for domestic certificate test of PV module is Pasan IIIb (Balval, Switzerland). The possible elements of the measurement uncertain that could effect electrical performance test of PV module are reference cell, spectrum correction, error from measurement repetition, test condition, stability and uniformity of artificial solar simulator. To find the measurement uncertainty, 6 men repeated the test by 10 times. And the results were that numerical average value was 124.44W and measurement uncertainty was $124.44W{\pm}0.36W$ with 95% confidence level for 125W PV module(KD-5125).

• KEPCO Journal on Electric Power and Energy
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• v.3 no.1
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• pp.9-16
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• 2017

The performance test is conducted for the purpose of determining the accurate thermal performance of the power generation facility or deriving the factors of thermal efficiency degradation. Compared to the acquisition method of power plant thermal performance test data by compensating cable or transmission cable, performance test using wireless instrument can acquire digital data in order to shorten the period due to installation and demolition of instrument and enhance safety of workers and relatively accurate data can be acquired thereby improving work efficiency. Wireless instruments have already been introduced to the market a long time ago, and some of them are used in industry such as petrochemical industry. However, there is no example which has been conducted for performance test of power generation facilities. In order to apply power generation facilities, a reliable system capable of acquiring performance data smoothly without affecting the control system is required. The wireless measurement system can eliminate the measurement defects and errors such as the damage due to the movement of the connecting cable, the extension due to the extension of the shield wire, the contact failure at the contact point between the measuring sensor and the connecting wire, This method has the advantage of collecting relatively accurate performance test data.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.1103-1104
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• 2006

This paper is described about the test equipment of fraction motor for electric train. This test equipment was able to perform the performance test of traction motor which was operated in Korea. We explain performance and function of test equipment. In order to check the performance of test equipment, we conducted the performance test with 200 kW and 1100 kW traction motor.

• New & Renewable Energy
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• v.3 no.1 s.9
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• pp.60-67
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• 2007

Catalyst coated membrane [CCM] type and catalyst coated substrate [CCS] type of membrane electrode assembly [MEA] were manufactured and evaluated their performance. Degradation test were conducted to find the difference of long term stability in two types of MEA and the factor for performance degradation problem occurred. Performance degradation test of single cell in two different types of MEA were carried out when current density was $200mA/cm^{2}$. The degradation test had proceeded for 230 hours and performance degradation was checked by I-V curve and impedance measurement at regular intervals. Also, MEA before/after operation and changes of catalyst layer were characterized by SEM, TEM, and XRD. Maximum power density of CCM type was higher than that of CCS type. Meanwhile, an increase of particle size of catalyst and an increase of impedance resistance after long term operation were observed. In the case of using CCM type MEA, the performance was deteriorated 38% of initial performance. In the case of using CCS type MEA, the performance was deteriorated 43% of initial performance. In consideration of difference of initial performance, performance of CCM type is higher than that of CCS type but both types had similar problems during degradation test.

• Communications for Statistical Applications and Methods
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• v.17 no.6
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• pp.853-863
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• 2010

The performance test in a public survey is conducted by a sample survey and the sampling rate of the performance test is a very important factor in the test process. Since the current sampling rate was decided empirically at an earlier time, it has been criticized for two points: the first is that it has a lack of a theoretical background on the decision for the sampling rate and the second is that the sampling rate should be improved in accordance with current test situations. In this paper, we review the present state of performance tests in public surveys in Korea and study the relationship between the rate of the performance test and fitness probability, number of tests, and the success rate in order to create a theoretical background to improve the test rate. In addition, we discuss relationship between the test rate and cost in the performance test.

• Nuclear Engineering and Technology
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• v.48 no.5
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• pp.1083-1095
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• 2016

The design of Prototype Gen-IV Sodium-Cooled Fast Reactor (PGSFR) has been developed and the validation and verification (V&V) activities to demonstrate the system performance and safety are in progress. In this paper, the current status of test activities is described briefly and significant results are discussed. The large-scale sodium thermal-hydraulic test program, Sodium Test Loop for Safety Simulation and Assessment-1 (STELLA-1), produced satisfactory results, which were used for the computer codes V&V, and the performance test results of the model pump in sodiumshowed good agreement with those in water. The second phase of the STELLA program with the integral effect tests facility, STELLA-2, is in the detailed design stage of the design process. The sodium thermal-hydraulic experiment loop for finned-tube sodium-to-air heat exchanger performance test, the intermediate heat exchanger test facility, and the test facility for the reactor flow distribution are underway. Flow characteristics test in subchannels of a wire-wrapped rod bundle has been carried out for safety analysis in the core and the dynamic characteristic test of upper internal structure has been performed for the seismic analysis model for the PGSFR. The performance tests for control rod assemblies (CRAs) have been conducted for control rod drive mechanism driving parts and drop tests of the CRA under scram condition were performed. Finally, three types of inspection sensors under development for the safe operation of the PGSFR were explained with significant results.