• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.10a
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• pp.163-166
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• 2004

Epoxy composite reinforced with 3-D braided Glass/Aramid hybrid fabric was fabricated. FBG sensor was embedded along the braid yam in order to monitor the changes of the complicated inner region of the 3-D braid structure. The good linearity between Bragg wavelength and temperature was verified by several preliminary experiments. The strain inside 3-D braided beam was estimated using FBG sensor system, and the result was compared with the calculated value. It was found that FBG sensor system is very useful technique to investigate inside region of complicated structure.

• Journal of the Optical Society of Korea
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• v.20 no.4
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• pp.524-529
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• 2016

Diagnostic sensors are demanded during plasma processes. Holograms of plasma taken with laser light without a reference beam were used to monitor behaviors of charged particles produced in nitrogen plasma as a function of electrode temperature ranging between 50 and 300℃. Holograms were characterized as a function of the pixel sum and grayscale value. Pixel sum calculated in identified grayscale ranges strongly correlated with ion density and emitted light intensity measured with a langmuir probe and optical emission spectroscopy, respectively. The performance was further evaluated with data acquired as a function of N₂ and NH₃ flow rates and improved correlations were observed in the new grayscale range. The confirmed correlations indicate that a hologram is a viable means to diagnose behaviors of plasma particles such as ions. Underlying principles are discussed in view of particle and charge composing vacuum and light.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.26-28
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• 2008

Soil moisture plays an important role in the land-atmosphere energy balance because it governs the partitioning of energy through latent heat fluxes or evapotranspiration. From the numerous studies, it is evident that the L-band radiometer is a useful and effective tool to measure soil moisture. The objective of the study is to develop and to verify the soil moisture retrieval algorithms for the L-band radiometer system. Through the radiometer-observed brightness temperature, surface emissivity and reflectivity can be derived, and, hence, soil moisture. We collect field and L-band airborne radiometer data from washita92, SGP97 and SGP99 experiments to assist the development of the retrieval algorithms. Upon launching the satellite L-band radiometer such as ESA-sponsored SMOS (Soil Moisture and Ocean Salinity) mission, the developed algorithms may be used to study and monitor globe soil moisture change.

• Proceedings of the IEEK Conference
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• 2000.06e
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• pp.121-123
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• 2000

Changes in breathing pattern and apnea both can be !he result of sleep disorders. The focus of this paper is to develop methodologies to monitor the breathing pattern and to detect apnea. An accurate recording of the respiratory phase can be carried out with different methods. One of these methods is the use of a thermocouple, which reacts to the variation in air temperature, placed in the nose and mouth of the patient. The K-type thermocouple was used because it has high reliability, thermo-stability, and good corrosion resistance. And also, it has a considerable long time constant that gives a low cut-off frequency, well below the respiratory frequency and thereby causing a large phase difference. The result showed that timing of respiration was accurately obtained with the AD595, amplifier for K-type thermocouple.

• Journal of information and communication convergence engineering
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• v.7 no.3
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• pp.412-417
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• 2009

With ubiquitous computing aid, it can improve human being's life quality if all people have more convenient medical service under pervasive computing environment. In this paper, for a pervasive health care application for diabetes patient, we've implemented a health care system, which is composed of three parts. Various sensors monitor both outer and inner environment of human such as temperature, blood pressure, pulse, and glycemic index, etc. These sensors form zigbee-based sensor network. And as a backend, medical information server accumulates sensing data and performs back-end processing. To simply transfer these sensing values to a medical team may be a low level's medical service. So, we've designed a model with context awareness for more improved medical service which is based on ART(adaptive resonance theory) neural network. Our experiments show that a proposed healthcare system can provide improved medical service because it can recognize current context of patient more concretely.

• Textile Coloration and Finishing
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• v.30 no.1
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• pp.1-8
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• 2018

In the present study, three morpholine substituted crystal violet lactone (CVL) have been synthesized to monitor the thermochromic property. This work is explaining the role of substituent on the lactone ring. The methyl substituents induced greater chromic effects than the chloro substituents. Furthermore, the three-component mixtures that contained CVL, bisphenol-A, and methyl stearate were used to analyse the thermochromic effect of the CVLs as bulk samples with various temperature. The thermochromic properties of the CVLs were evaluated using solid-state UV-Vis and FT-IR spectroscopic techniques. Finally, one of the synthesized CVL has been successfully converted into the form of a test paper similar to pH paper for use as thermal indicators.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.36-39
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• 2000

The Ministry of Construction and Transportation is going to establish 310 groundwater monitoring stations. 154 stations have been established and periodically managed since 1995. Most of stations have two monitoring boreholes which function is to monitor the unconsolidated and bedrock aquifer, and have the automatic monitoring equipment to observe groundwater level, temperature and hydraulic conductivity which are measured four times a day. Especially 44 stations are equipped with the Remote Terminal Unit. MOCT publish "an annual report of Groundwater monitoring stations" every year and everyone can get the monitoring data from Groundwater World web site(http://wamis.kowaco.or.kr/gww/)..kr/gww/).

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.04a
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• pp.136-141
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• 2011

In a power plant, an oil and steam leakage is generated once in a while. This is because the operating temperature and pressure of oil are very high. It is very difficult to monitor oil leakage, because oil leakage is almost invisible. Therefore a method to oil leakage detecting quickly and accurately is needs. In this paper, we proposed the method for the detecting oil leakage by using image processing and CCTV. To test the performance of this technique, experiments have been performed for simple case. Results show that the proposed technique is quite powerful in the oil leak detection.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2001.11a
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• pp.252-259
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• 2001

Integrated condition monitoring is required to monitor effectively the machine conditions since machine failures could not be monitored accurately by any single measurement parameter. Application of various condition monitoring techniques is therefore preferred in many cases in order to diagnosis the machine condition. However it inevitably requires lots of maintenance cost and sometimes it could be proved to over-maintenance unnecessarily. This could happen especially when one measurement parameter closely correlates to another. Therefore correlation analysis of various monitoring parameters has to be performed to improve the reliability of diagnosis. In this work, Pearson correlation coefficient was used to analyze the correlation between condition monitoring parameters of an over-loaded machine system where the vibration, wear and temperature were monitored simultaneously. The result showed that Pearson correlation coefficient could be regarded as a good measure for evaluating the availability of condition monitoring technology.

• Tribology and Lubricants
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• v.18 no.2
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• pp.117-126
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• 2002

Abstract - An integrated condition monitoring algorithm based on an expert system was implemented in this work in order to monitor effectively the machine conditions. The knowledge base was consisted of numeric data which meant the posterior probability of each measurement parameter for the representative machine failures. Also the inference engine was constructed as a series of statistical process, where the probable machine fault was inferred by a mapping technology of pattern recognition. The proposed algorithm was, through the user interface, applied for an air compressor system where the temperature, vibration and wear properties were measured simultaneously. The result of the case study was found fairly satisfactory in the diagnosis of the machine condition since the predicted result was well correlated to the machine fault occurred.