• 한국유체기계학회 논문집
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• 제5권1호
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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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• 유체기계공업학회 2001년도 유체기계 연구개발 발표회 논문집
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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.

• 한국항공우주학회지
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• 제30권5호
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• pp.62-70
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• 2002

항공기용 가스터빈엔진에 대한 경제적인 시험 기법 개발을 위해 천이상태 성능 시험 결과로부터 정상상태 성능을 예측할 수 있는 방안을 모색하였다. 천이상태 성능과 정상상태 성능이 상이한 원인을 동역학적 천이 효과, 열적 천이 효과, 공기역학적 천이 효과로 구분하고, 각각을 모델링해서 엔진의 천이상태 성능을 통해 정상상태 성능을 계산하는 보정 인자를 정량화 하였다. 엔진 성능시험은 한국항공우주연구원이 보유한 고공환경시험설비에서 이루어졌다. 먼저 천이상태 성능시험 시 나타나는 엔진 입 출구의 온도 변화가 엔진 성능에 미치는 영향을 보정했으며, 그 후 도입된 보정 인자를 사용해 정상상태 성능을 예측하였다. 이렇게 예측된 결과와 실제 정상상태 성능시험 결과를 비교한 결과, 연료 소모량의 차이 3.68% 이내로 정상상태 성능을 예측할 수 있어, 본 연구에서 사용한 보정 기법이 상당한 정도의 정확도를 보장하고 있는 것으로 나타났다.

• 대한통합의학회지
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• 제10권2호
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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.

• 한국태양에너지학회 논문집
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• 제27권1호
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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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• 제3권1호
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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.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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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.

• 신재생에너지
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• 제3권1호
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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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• 제17권6호
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• pp.853-863
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• 2010

공공측량에서 성과 심사는 표본조사로 이루어지기 때문에 성과심사에서 심사비율은 매우 중요한 요인이다. 현행 성과심사 심사비율은 성과심사 제도 실시 초기에 경험적으로 결정되었기 때문에 이론적인 바탕이 부족하다는 지적과 함께 최근의 심사 여건에 맞도록 심사비율을 개선해야 한다는 의견이 제기되었다. 본 논문에서는 현재 우리나라에서 이루어지고 있는 공공측량 성과심사의 현황을 개략적으로 알아보고 현행 성과 심사 심사비율을 개선하기 위한 이론적 토대로서 성과심사 심사비율과 적합확률, 심사대상 수, 합격 비율의 관계를 살펴본다. 또한 성과심사 심사비율과 심사비용과의 관계를 토의한다.

• Nuclear Engineering and Technology
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• 제48권5호
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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.