• KSBB Journal
• /
• v.16 no.2
• /
• pp.123-127
• /
• 2001

For testing antimicrobial activity of functional plastics containing antimicrobial agent. We have used Escherichia. coli (ATCC 25922) and Staphylococcus. aureus (ATCC 6538P) with plastics which contained a Ag-hydroxyl apatite agent. In this paper, effect of antimicrobial test on plastics containing silver complex agent which accomplished by using test condition that Trypticase Soy Broth (TSB solution have diluted 500 times with 0.1 M phosphate buffer), pH7.2, Temp. $37\pm1^{circ}C$ and 120 rpm for 24 hr. the condition give the opportunity to better perform the antimicrobial active effect of individual functional plastics. As result. the test conditions were best effect of antimicrobial by using plastic contained minimum 0.5% with Ag-hydroxyl apatite agent.

• The Transactions of the Korea Information Processing Society
• /
• v.6 no.12
• /
• pp.3634-3641
• /
• 1999

LAN Emulation and IPOA are the two most widei y accepted network protocols which allow to provide conventional LAN-based data services on ATM LAN environment. In this paper, the performance of IPOA and LAN Emulation on ATM LAN testbed is compared and the results are compared with performance of Ethernet as well. For performance comparison, metrics such as application throughput, latency, CPU usage are used. In addition, a network program that uses the socket based TCP/IP application programming interface to send large data files from client to server via ATM LAN switch is developed. IPOA provides lower latency and higher throughput than LAN Emulation while LAN Emulation consumes more CPU usage.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.29 no.2
• /
• pp.108-113
• /
• 2009

MFL(magnetic flux leakage) inspection is a general method of non-destructive evaluation(NDE) of underground gas pipelines. Pipelines are magnetized by permanent magnets when MFL PIG(pipeline inspection gauge) gets through them. If defects or corrosions exist in pipelines, effective thickness is changed and thus variation of leakage flux occurs. The leakage flux signals detected by hall-sensors are analyzed to characterize defect's geometries such as length, width, depth, and so on. This paper presents several methods for estimating defect's length using MFL signals and their performances are compared for real defects carved in KOGAS pipeline simulation facility. It is found that 80% and 90% of minimum values for axial and peak values for radial signals respectively show the best performance in the point of length estimation error.

• Journal of the Society of Naval Architects of Korea
• /
• v.34 no.4
• /
• pp.21-30
• /
• 1997

This paper describes the experimental method of a pod-type waterjet propulsion system in a towing tank and shows the experimental analysis and test results of a designed waterjet propulsion system to be used for a hybrid high speed craft. The cruising performance of this craft is estimated from the results of the hull resistance test and waterjet test under the assumption that the interaction between the hull and the inlet pod is very small. A pod-type waterjet system with an axial pump was designed and a stand-alone waterjet experimental system was developed. Useful data such as the pump performance, the jet efficiency, the losses of inlet duct and nozzle were obtained. Test results show a good agreement with the design requirement.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 1996.11a
• /
• pp.97-104
• /
• 1996

DYGABCD 프로그램을 이용해 선형모델의 구성에 필요한 시스템 행렬을 구하고 최소자승법을 이용하여 실시간 선형모사를 행한 후 DYNGEN 프로그램을 이용한 비선형 모사와 비교하여 그 타당성을 입증하였다. 그리고 가제어성과 가안정성을 시험하여 시스템에 대해 제어기설계가 가능한지 확인하고 엔진의 성능과 직결되는 터빈입구 온도의 Overshoot 제어를 위해 고전적 제어기법인 PI제어기와 현대적 최적제어기법인 LQR 제어기를 설계하여 각각의 성능을 비교해 보았다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2013.06a
• /
• pp.200-203
• /
• 2013

본 논문에서는 시장 점유율 상위를 차지하는 3 종의 해외 유명 제조사의 상용 HD 급 실시간 방송용 H.264 인코더의 화질 성능에 대해 전 기준 화질 평가를 통해 비교한다. 이를 위해 VQEG(Video Quality Experts Group)등에서 배포하는 9 종의 기준영상을 이용하여 PSNR(Peak Signal to Noise Ratio)을 측정하였으며 인코더 별 성능 비교를 위해 9 종의 기준영상에 대한 평균 PSNR 과 인코더/디코더의 전체 지연시간을 측정하였다. 그 결과 장비 별로 조금씩 다른 특성 결과와 현재 H.264 인코더 시험 시 성능 평가의 애매한 부분이었던 화질에 대한 벤치마크 결과를 얻을 수 있었다. 본 논문의 실험 결과는 국산 방송용 인코더의 객관적인 성능 평가를 위한 지표로 사용될 수 있을 것으로 예측된다.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.19 no.1
• /
• pp.78-84
• /
• 2013

The primary objective of the current work is to develop efficient numerical code to assess the resistance performance of the twin hull form. Resistance performance for the two different twin hull forms with asymmetric and symmetric mono hull using developed code are evaluated. Numerical calculations and model tests have been compared to validate a developed code used in the current work. Comparison were carried out through sinkages of the bow and stern, trim angle and wave-making resistance. Comparative analysis regarding hydrodynamic characteristic of different twin hull forms is worthy of application in the hull form development stage.

• Journal of IKEEE
• /
• v.18 no.2
• /
• pp.185-191
• /
• 2014

In this paper, we have implemented the low temperature fluidity test system with the composited package fuel heater, which has tested the low temperature fluidity and start time to evaluate the performance. Then we have compared the separation and the unified fuel heater type at $+20{\sim}-30^{\circ}C$. Also, we have tested the flowing pressure and start time, power consumption of heater. By comparing the performance with several condition, the experimental results obtain an improved start time of 23% and low temperature fluidity of 19%.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2010.11a
• /
• pp.423-431
• /
• 2010

In order to investigate the effect of fuel injection hole configuration within the scramjet combustor, experiment and quasi-one-dimensional analysis was performed. And the results were compared with experiment and analysis result which were performed in 2008 with same facility and test condition. Fuel injection hole size was decreased and quantity was increased. However the depth of fuel penetration and fuel flow were maintained. As a test result, combustion performance was increased significantly with no-cavity injector and slightly with plain-cavity. However, combustion performance with zigzag-cavity was decreased.

• Journal of Radiation Protection and Research
• /
• v.19 no.2
• /
• pp.133-145
• /
• 1994

Recently, the Ministry of Science and Technology issued a Ministerial Ordinance (No 1992-15) about the technical criteria on personnel radiation dosimetry. In today's climate, it is important to demonstrate and document that the processor's systems and services to others meet national standards of quality. The purpose of this study is to verify the performance of the Teledyne PB-3 personnel dosimetry system that is generally used in Korea Atomic Energy Research Institute(KAERI) by intercomparison with Oak Ridge National Laboratory. The KAERI has been participated in this personnel dosimetry intercomparison study(PDIS) program since 1991 and it could be possible to test and calibrate personnel monitoring system. This report presents a summary and analysis of by about 50 dose equivalent measurements reported for PDIS-16 through 18 (1991 -1993) with emphasis on neutron dose equivalent sensitivity, accuracy and precision. Relationships of the PDIS results to occupational neutron monitoring and methods to improve personnel dosimetry performance are also discussed.