• 한국유체기계학회 논문집
• /
• 제17권3호
• /
• pp.25-32
• /
• 2014

The main objective of this study is to validate the performance characteristics of newly developed micro propeller turbine based on experimental model test. For this purpose, Measurements of efficiency and cavitation tests with variations on the guide vane opening, blade rotational speed, head and load are carried out according to the IEC standard for model testing. From the tests and scale up calculation, the maximum prototype and model efficiency of the runner blade reaches as high as 90.87 % and 90.27 % respectively. Test results show that good cavitation behavior is covered in the range of output 50kW and 100 kW.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2007년도 추계학술대회 논문집
• /
• pp.569-574
• /
• 2007

The paper presents an application of the model to a practical problem of train-induced vibrations. The aim of this study is to vertify for performance of isolators which was developed in KRRI supported floating slab track. Laboratory tests on developed isolations show that the energy dissipation, under cyclic loading of constant amplitude, can be suitably represented by a combination of a viscous and a hysteretic damping. Also, other tests for structural performance are carried out, such as elastic material test, compression test and so on. The specimen, $400{\times}400{\times}300mm$, is placed between two stiff steel plates designed to uniformly distribute the compression stress on the surface.

• 품질경영학회지
• /
• 제24권3호
• /
• pp.37-49
• /
• 1996

For highly reliable devices it is often defined to "fail" when its performance degrades below a specified value. In this paper we consider a method for optimally designing accelerated degradation tests(ADTs) in which the performance over exposure time and stress has Weibull distribution. For the product whose performance has Weibull distribution, the optimum plan - low stress level and sample proportions allocated to each test condition - is obtained, which minimize the asymptotic variance of maximum likelihood estimator of a stated quantile at design stress. We also present compromise ADTs plan that can be used for the practical purpose.

• 한국해양공학회지
• /
• 제19권3호
• /
• pp.25-30
• /
• 2005

To predict rolling performance for a barge-type FPSO, the evaluation of correct nonlinear roll damping is critical. The square section of FPSO causes a considerable viscous damping effect. Free roll decay tests were carried out to estimate nonlinear roll damping for a barge-type FPSO, under three different conditions. The roll motion RAO was deduced from model tests in the wave condition of the wideband spectrum. In numerical calculation, the quadratic damping was considered as equivalent linear damping, using the results of free roll decay test. Tested roll performance in the JONSWAP wave spectrum was compared with numerical results. These two results shaw good agreement, in spite of the proximity of peak wave period and roll natural period.

• 수산해양기술연구
• /
• 제41권3호
• /
• pp.222-226
• /
• 2005

A series of model tests carried out at the CWC of WJFEL for the purpose of prediction of resistance for the performance and improvement of resistance by attaching appendage for the ship of 50 knots class planing hull. The resistance performance evaluation has been carried out for the bare hull and for the appendage hull with two different depth of vertical type wedges. In the bare model test, trim and sinkage is calculated for the planing hull and the resistance is calculated. For minimizing the resistance, wedge appendage is attached and tested. Analysis and tests shows that for a 12.5mm wedge, resistance is minimum and overall power tallied to 5636ps.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2009년도 춘계 학술발표회
• /
• pp.222-232
• /
• 2009

In this study, the real site test conditions were considered and applied to suggest the improved test method for geosynthetics chemical resistance. For this, index and performance tests were done to specify and regulate the more approached test method. Accelerated model by Arrhenius equation was applied to interpretate the experimental data. Through analysis and comparison the overall experimental results, we could suggest the possibility and setup the advanced chemical resistance test method for geosynthetics.

• 항공우주기술
• /
• 제10권1호
• /
• pp.122-128
• /
• 2011

액체로켓엔진용 산화제펌프의 수류시험을 상온에서 실시하였다. 수력성능시험 결과, 펌프의 양정 계수는 회전수가 커질수록 약간 감소하였고, 효율은 회전수가 커질수록 증가하였다. 흡입성능시험 결과, 유량비 92% 이하의 낮은 유량비에서 흡입성능이 떨어지는 것으로 나타났다. 또한, 시험 중 측정한 고주파 신호를 이용하여 펌프의 진동 특성을 분석하였다.

• 자동차안전학회지
• /
• 제7권1호
• /
• pp.13-19
• /
• 2015

Recently, Child safety has become one of the issue with Q10 dummy representing large child. The objective of this paper was to evaluate performance of three child restraints system (backless booster, high-back booster and without booster) by changing D-ring location in the rear seat. Sled tests were carried out with a Q 10 in 64km/h frontal impact. Before the dynamic sled tests, we assessed dummy positioning with difference in CRS types and height adjustment positions. Dynamic sled test results indicated that there is different performance of CRS types and belt routing. These test results will use as base line data for development CRS safety performance for Q 10.

• 한국분말야금학회:학술대회논문집
• /
• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
• /
• pp.857-858
• /
• 2006

In order to clarify the wear resistance as cutting tools, the effect of oxygen addition on oxidation behavior of the ${\beta}-Si_3N_4$ ceramics with 5 mass% $Y_2O_3$ and 2 or 4 mass% $Al_2O_3$ was investigated by performing oxidation tests in air at $1300^{\circ}$ to $1400^{\circ}C$ and cutting performance tests. From test results, we could conclude that the mechanical properties of ${\beta}-Si_3N_4$ ceramics depending on oxygen introduction are much effective on cutting performance improvements of ${\beta}-Si_3N_4$ ceramics.

• 한국지진공학회논문집
• /
• 제20권1호
• /
• pp.71-77
• /
• 2016

In this study, the seismic performance of connections between filled composite beam (CG beams) and forming angle composite (FAC) column was experimentally evaluated. First, the bending tests were conducted on two CG beams and the axial tests were conducted on two FAC columns. Then, based on these preliminary test results, the cyclic loading test were performed on two interior connections between CG beam and FAC column. The main difference of two specimens is the plate shape of the CG beam. The test results showed that both specimens achieved the maximum story drift capacity over 0.04 radian which is required for special moment frame.