• Nuclear Engineering and Technology
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• v.44 no.7
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• pp.735-744
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• 2012

In order to quantify the flow distribution characteristics of APR+ reactor, a test was performed on a test facility, ACOP ($\underline{A}$PR+ $\underline{C}$ore Flow & $\underline{P}$ressure Test Facility), having a length scale of 1/5 referring to the prototype plant. The major parameters are core inlet flow and outlet pressure distribution and sectional pressure drops along the major flow path inside reactor vessel. To preserve the flow characteristics of prototype plant, the test facility was designed based on a preservation of major flow path geometry. An Euler number is considered as primary dimensionless parameter, which is conserved with a 1/40.9 of Reynolds number scaling ratio. ACOP simplifies each fuel assembly into a hydraulic simulator having the same axial flow resistance and lateral cross flow characteristics. In order to supply boundary condition to estimate thermal margins of the reactor, the distribution of inlet core flow and core exit pressure were measured in each of 257 fuel assembly simulators. In total, 584 points of static pressure and differential pressures were measured with a limited number of differential pressure transmitters by developing a sequential operation system of valves. In the current study, reactor flow characteristics under the balanced four-cold leg flow conditions at each of the cold legs were quantified, which is a part of the test matrix composing the APR+ flow distribution test program. The final identification of the reactor flow distribution was obtained by ensemble averaging 15 independent test data. The details of the design of the test facility, experiment, and data analysis are included in the current paper.

• Biomolecules & Therapeutics
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• v.3 no.3
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• pp.242-244
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• 1995

In vitro cell culture system has been proposed as a promising alternative model to in vivo skin irritation test. These studies were performed to screen the cytotoxicity effects of surfactants using normal human skin fibroblasts. Cell membrane integrity assessed by the leakage of lactate dehydrogenase (LDH) and mitochondrial integrity by MTT [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromides reduction test were affected in a dose dependent manner. The irritation potential of surfactants to human skin patch test, and the changes of capillary permeability by rabbit intradermal safety test were assessed as in vivo methods. Our results suggest that LDH leakage assay and MTT reduction test using cultured human fibroblasts could be predictive for the irritancy of various surfactants in human, and LDH assay is superior correlated with in vivo test (r=0.886) to MTT test with in vivotest (r=0.757).

• Tribology and Lubricants
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• v.34 no.6
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• pp.300-306
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• 2018

In this study, the performance of foil thrust bearings was investigated by performing bearing take-off and load capacity tests, using an in-house designed and manufactured vertical bearing test rig. The mean take-off rotational speed and maximum load capacity of the bearing specimen were ~18,000 rpm and ~80 kPa, respectively. The vertical bearing test rig was observed to yield higher coefficients of friction and frictional torques than a horizontal bearing test rig under identical test conditions. This was a result of its structural characteristics, in that the bearing specimen is placed atop the thrust runner, which keeps it from being separated from the runner after the bearing take-off. In addition, bearing take-off was observed at a higher runner rotational speed as this structure keeps air from flowing between the top foil and runner surfaces, which requires a higher runner speed. The parallel alignment between the bearing specimen and runner surfaces can be maintained within a certain range more easily in a vertical test rig than in a horizontal test rig. Because of these advantages, Korean Industrial Standard, KS B 2060, recommends a vertical bearing test rig as the standard test device for foil thrust bearings.

• Proceedings of the Zoological Society Korea Conference
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• 2001.10a
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• pp.131.2-131
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• 2001

No Abstract, See Full Text

• Proceedings of the KIEE Conference
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• 1999.07c
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• pp.1437-1439
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• 1999

This paper describes test method though low voltage power system implementation for high impedance fault relay test before its operation in real power system. Through this test, relay tested its function and algorithm. In this paper, we will provides test method using low voltage power system and its results.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.10a
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• pp.701-702
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• 2005

• Journal of the Korean Institute of Telematics and Electronics B
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• v.31B no.9
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• pp.1-9
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• 1994

This paper analyzes the faults and their mechanism of CMOS ICs using IDDQ testing technique and evalutes the reliability of the chips that fail this test. It is implemented by the three testing phases, initial test, burn-in and life test. Each testing phase includes the parametric test, functional test, IDDQ test and propagation delay test. It is shown that the short faults such as gate-oxide short, bridging can be only detected by IDDQ testing technique and the number of test patterns for this test technique is very few. After first burn-in, the IDDQ of some test chips is decreased, which is increased in conventional studies and in subsequent burn-in, the IDDQ of all test chips is stabilized. It is verified that the resistive short faults exist in the test chips and it is deteriorated with time and causes the logic fault. Also, the new testing technique which can easily detect the rsistive short fault is proposed.

• Journal of the Korea Institute of Military Science and Technology
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• v.22 no.6
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• pp.784-796
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• 2019

As the size and complexity of software increases, it is important to ensure the quality of software through testing. Many organizations refer to international standards or test process models to improve the quality of software through establishing a systematic test process. However, these standards and process models provide general processes that do not reflect the characteristics of the domain or the organization's test policies and strategies. To establish a test process that reflects the characteristics of the organization, test policies and strategies based on the organization's quality objectives and the organizational and domain characteristics should be reflected. This study proposes specific methods for eliciting activities and information to establish organizational software test policies and strategies that are essential to establishing a test process that reflects the characteristics of the organization and the system.

• Journal of the Korean Society of Propulsion Engineers
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• v.22 no.3
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• pp.119-127
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• 2018

A test stand for an altitude test of reciprocating engine was designed, manufactured and validated by preliminary tests and simple calculations. The test stand was designed to interface with the altitude turbo-shaft engine test facility of Korea Aerospace Research Institute. Many limiting conditions for altitude test of reciprocating engine were assumed and the test stand was developed to satisfy these limitations. The test stand design was focused especially on the altitude, Mach number and fuel temperature control for reciprocating engine altitude tests with smaller air and fuel flow than those of turbo shaft engines.

• Journal of the Society of Naval Architects of Korea
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• v.59 no.5
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• pp.296-305
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• 2022

In order to investigate maneuvering characteristics of KCS in waves, captive model test in regular waves was conducted. Purpose of the test is measuring maneuvering hull forces when ship is maneuvering in waves. Model test was carried out using CPMC (Computerized Planar Motion Carriage) of ocean engineering basin in KRISO (Korea Research Institute of Ships and Ocean engineering). Total 6 degrees-of-freedom motion were fixed by two points supporting captive model test device, which is specially designed for this test. This system estimates 6 degrees-of-freedom forces and moments through 12 strain gauge signals. Mapping matrix from strain gauge signals to 6 degrees-of-freedom forces and moments was derived by a well-organized calibration test. Static drift test was conducted in calm sea and in regular waves with various wave conditions. Hydrodynamic coefficients related to drift angle were extracted for each wave conditions, and the effect of waves on course stability was analyzed.