• Journal of the Korean Society of Safety
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• v.6 no.4
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• pp.21-27
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• 1991

Acoustic Emission was monitored during tensile test and loading-holding-unloa-ding cycle test for two types (notched and unnotched) of CFRP specimens. AE activities showed that the fiber breakage during tensile tests depended upon the specimen geometry. We obtained new AE parameter such as the ration (damage ratio= AE events during unloading test / AE events during loading test) and the felicity ratio from which we investigated dynamic fracture process of CFRP specimens. The damage ratio of AE events was shown to be a good indicator to distinguish the generated fracture mechanism, such as fiber breakage and delamination. Also, ultrasonic testing results after loading-holding-unloading cycle test were good agreement with AE test results to detect defects or fiber breakage.

• Proceedings of the Korea Information Processing Society Conference
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• 2005.05a
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• pp.491-494
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• 2005

기업의 웹사이트는 기업의 환경 변화를 주도하는 관문으로서의 역할을 하고 있다. 그러나 현재 기업의 웹사이트 평가지표에 대한 연구는 진행되지 않고 연구의 대부분이 웹사이트의 외형적인 측면들을 평가하고 있다. 특히 e-Biz 측면에서 전자상거래 주체인 B2B(Business to Business) 웹사이트에 대한 연구는 거의 이루어 지지 않고 있어, 기업 관점의 웹사이트 평가와 B2B 웹사이트에 대한 평가지표 연구가 필요하다. 본 연구는 평가지표 KPI(Key Performance Indicator)를 도출하고, AHP(Analytic Hierarchy Process) 기법으로 웹사이트 평가 연구를 통하여 평가지표를 추출한 후 B2B에 적용함으로써 각 지표들의 중요도 및 가중치의 차이를 살펴본다. 이를 통해 기업과 기업간에 전자상거래 규모의 확대에 따른 의사결정과 B2B 웹사이트를 보다 쉽게 설계 할 수 있는 명확한 기준을 제시하였다.

• 유체기계공업학회:학술대회논문집
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• 2004.12a
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• pp.153-159
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• 2004

We have investigated the feasibility of using differential pressure(pressure drop) of gas turbine meter to diagnose turbine performance degradation caused by mechanical wearing damage and/or dirt buildup or erosion. If the differential pressure between the upstream piping and the throat of a turine meter can be correlated to meter flow rate over the operating range of the meter, then a relatively simple differential pressure measurement in the filed might be used to detect meter performance changes. To test this method, we have conducted two experimental simulation on Straightener Integrated Type(SIT) turbine meter. One is fur dirt buildup on turbine blade, the other is for eccentricity of the blade. Results show that this method provide a reliable measure of performance degradation and is useful maintenance indicator.

• Journal of Aerospace System Engineering
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• v.8 no.3
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• pp.20-26
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• 2014

This paper presents the procedures and the results of the pitch control force via flight test for a light airplane in order to make out the stability of the aircraft and the compliance with concerned regulation. The flight test procedures were determined in order to obtain the aircraft type certification. The instrumentation equipments including airspeed indicator, accelerometer, and pitch control force measurement tools are used to perform the flight test. For the flight test, the airspeed and the pitch control force with related normal acceleration are measured sustaining turn flight with bank angle derived from trim speed. The flight test results showed that the handling qualities of the airplane are complied with the KAS-23, the regulation of the Korean government for the light airplane type certification.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.3
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• pp.725-732
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• 2011

There are some trials to adopt the RFID/USN technologies at container terminals for effective terminal operations. In this paper, we propose a realtime location recognition method for stacked containers under the assumption that each container has a wireless sensor node to measure the RSSI values from neighbor nodes. We develope an RSSI based location algorithm with performance evaluations by RSSI measurement and application program implementation.

• ETRI Journal
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• v.28 no.3
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• pp.265-274
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• 2006

Recent advances in positioning and photogrammetry technologies have made it possible to build a mobile mapping system (MMS) that can obtain 3D coordinates of geographic objects from stereo images recorded from a moving vehicle. In this paper, we present a design and detailed implementation of an MMS called a 4S-Van. Furthermore, we present four issues that have made major contributions to the performance of an MMS: 1) CCD camera calibration, 2) GPS signal condition, 3) integrating a GPS, inertial navigation system (INS), distance measurement indicator (DMI), and CCD cameras, and 4) the orientation angle of CCD cameras. In the experimental results, the performance of an MMS was analyzed for each component, giving an idea of how to effectively design and integrate each component in developing an MMS to get a maximal accuracy of 3D coordinates.

• KSBB Journal
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• v.13 no.4
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• pp.337-342
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• 1998

Immunosensor for the determination of LDL(Low-Density Lipoprotein), a good indicator for the diagnosis of atherosclerosis and hypercholesterolemia, was developed by using quartz crystal microbalance(QCM). The immunosensor consists of flow-through cell, oscillating circuit, oscilloscope, and frequency counter. FIA(Flow Injection Analysis) was applied to the QCM system for the measurement of LDL in liquid phase. Antibody showing binding affinity against LDL was immobilized on the gold electrode of a quartz crystal by covalent coupling via polyethylenimine / glutaredehyde. LDL was injected and bound to the antibody immobilized on the QCM immunosensor. The response of the immunosensor (F0 - F1) was found to be proportional to the LDL concentration from 200 $\mu\textrm{g}$/ml to 800 $\mu\textrm{g}$/ml. Operational conditions for the operation of immunosensor were also investigated in terms of sensitivity and non-specific binding.

• Journal of Microbiology and Biotechnology
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• v.12 no.2
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• pp.268-272
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• 2002

Kinetic experiments on the biological oxidation of $Fe^{2＋}$ by Acidithiobacillus ferrooxidans were conducted by measuring the total organic carbon content. The total organic carbon in the solution was determined with different initial concentrations of $Fe^{2＋}$(4, 9, 15, and 20 mg/ml). The growth of At. ferrooxidans and substrate utilization were described by the Monod expression. The total organic carbon was found to be an indicator of the biomass concentration and thus may be effectively utilized for estimating cell growth rates in kinetic model development.

• Journal of the Korean Society of Safety
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• v.28 no.1
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• pp.35-39
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• 2013

The flash point is an important indicator of the flammability of a chemical. In this study, the flash points for the n-propanol+n-butanol and n-propanol+acetic acid systems were measured by Tag open-cup apparatus. The experimental data were compared with the values calculated by the Raoult's law and optimization method based on van Laar and UNIQUAC equations. The calculated values by optimization method were found to be better than those based on the Raoult's law.

• Korean Journal of Veterinary Research
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• v.35 no.3
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• pp.631-633
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• 1995

70 cows with abomasal torsion and 71 cows with right-side displacement of the abomasum were examined to determine whether the preoperative blood base-excess concentration could be used both as a prognostic indicator for postoperative recovery in cows with abomasal torsion and as an aid in differentiating between abomasal torsion and right-side displacement of the abomasum. The survival rate of cows with abomasal torsion decreased as the base-excess concentration decreased(P=0.08). There was a significant difference(P<0.025) among base-excess ranges between abomasal torsion and right-side displacement of the abomasum. Most cows with base-excess concentrations ${\geq}15.0mEq/L$ and ${\leq}-0.5mEq/L$ had abomasal torsion, rather than right-side displacement of the abomasum.