• Journal of Chest Surgery
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• v.28 no.11
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• pp.973-976
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• 1995

The assessment method of human body composion by bioelectrical impedance is very simple, safe, rapid and noninvasive. Based on prediction formulas for total body water from bioelectrical impedance, the observed weight loss should be associated with an increase in impedance. However in edematous patients for dialysis, the calculated total body water loss as calculated from impedance were overestimated and significantly higher than the weight loss after dialysis. So determination of impedance were made in 50 edematous patients before, during and after dialysis. Mean weight loss, which was assumed to be only loss of water was 1719$\pm$ 866 gr and mean impedance change was 71.0 $\pm$ 23.0 Ohm under 50kHz. Body weight loss was highly correlated [r>0.81 with the increase in body impedance under variable frequencies[1, 10, 20, 30, 40, 50 kHz . But there were no differences between frequences. In conclusion, clinical application of bioelectrical impedance method is useful for individual edematous patients with new correlation equation[Y=230+26.8X, X;Impedance change, Y;Calculated total body water loss .

• Rapid Communication in Photoscience
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• v.3 no.4
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• pp.76-78
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• 2014

Fluorescent nucleic acids were prepared utilizing the polymerase extension (PEX) reaction to incorporate fluorescent molecules. 2'-Deoxyuridine triphosphate (dUTP) derivatives possessing pyrene molecules as fluorophores were synthesized using the aqueous-phase Sonogashira coupling between 5-Iodo-dUTP and acetylene-linked pyrene molecules. The incorporation of the pyrene (Py)-labeled deoxyuridine triphosphates (PyU) into DNA by polymerase was evaluated by polyacrylamide gel electrophoresis, demonstrating that the PyU can work as a good substrate for the PEX reaction. The fluorescent properties of the functionalized DNA prepared by the PEX reaction were characterized by steady-state fluorescence measurements. The Py-conjugated DNA showed typical emission spectra of the pyrene, and the DNA with two pyrene molecules connected to each other by a diethylene glycol linker exhibited a broadened emission attributed to the electronic interaction between the Py molecules.

• Journal of Biosystems Engineering
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• v.28 no.5
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• pp.465-468
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• 2003

A microdialysis coupled flow injection amperometric biosensor was calibrated to measure the concentration of glucose using 7 standard samples from 10ml to 70ml of glucose solution. The output of the sensor increased linearly with an increase in the glucose concentration with an $R^2$ correlation of 0.99. The amperometric biosensor was then applied to measure the. glucose concentration of 2 commercial samples(Orange and Pineapple juice) and the results compared with HPLC. Around 12% error was observed in glucose concentration measurements of the samples analyzed. The sensor has potential in rapid measurement once the calibration is done. Potential for on-line sensing is also discussed.

• Journal of Biomedical Engineering Research
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• v.26 no.5
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• pp.271-282
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• 2005

There are strong demands for accurate, fast, and inexpensive devices in the medical diagnostic laboratories, such as biosensors and chemical sensors. Biosensors can provide the reliable and accurate informations on the desired biochemical parameters, which is an essential prerequisite for a patient before going for a treatment. They can be used for continuous measurements of metabolites, blood cations, gases, etc. Of these, electrochemical biosensors play an important role in the improvement of public health, because rapid detection, high sensitivity, small size, and specificity are achievable for clinical diagnostics. In this paper, the clinical applications with electrochemical biosensors are reviewed. An attempt is also made to highlight some of the trends that govern the research and developments of the important biosensors that are associated to clinical diagnosis.

• Journal of Astronomy and Space Sciences
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• v.32 no.2
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• pp.101-112
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• 2015

Magnetic reconnection is a fundamental process occurring in a wide range of astrophysical, heliospheric and laboratory plasmas. This process alters magnetic topology and triggers rapid conversion of magnetic energy into thermal heating and nonthermal particle acceleration. Efforts to understand the physics of magnetic reconnection have been made across multiple disciplines using remote observations of solar flares and in-situ measurements of geomagnetic storms and substorms as well as laboratory and numerical experiments. This review focuses on the progress achieved with solar flare observations in which most reconnection-related signatures could be resolved in both space and time. The emphasis is on various observable emission features in the low solar atmosphere which manifest the coronal magnetic reconnection because these two regions are magnetically connected to each other. The research and application perspectives of solar magnetic reconnection are briefly discussed and compared with those in other plasma environments.

• Proceedings of the Materials Research Society of Korea Conference
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• 1992.05a
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• pp.14-14
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• 1992

During the past five years a very successful effort has been made to improve existing and develop new aluminium alloys. The progress achieved has been possible because of the development of new production methods, such as powder metallurgy and spray/deposition. These methods make use of rapid solidification process which alloys compositions other than those achieved by conventional ingot metallurgy. The ingot metallurgy of the 2000 and 7000 series used thus far, as well as the age hardening Al-Li alloys, show several disadvantages caused by the production process. Such problems are primarily coarse intermetallic constituent phases, coarse grains and macrosegregation, resulting in low fracture toughness. The present contribution reports results of an experimental investigation performed on a modern high strength spay deposited aluminium alloy of the Al-Zn-Mg-Cu (7075 and the modified 7150X) type. Results are given in terms of its microstructural characterization by using X-ray diffractomertry and transmission electron microscopic. The mechanical propierties of those alloys in the as-extruded and extruded+aged condition were evaluated by using microhardness Vickers, tensile test and fracture toughness measurements.

• Journal of Korean Society of Water and Wastewater
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• v.24 no.3
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• pp.333-339
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• 2010

Particle removal is an important step taken at water treatment plants (WTPs) for the safety of tap water due to its proportionality to the pathogen inactivation. Government promulgated a treatment technique for the optimization of filtration including continuous turbidity monitoring using on-line turbidimeters. Based on the turbidity measurements of 460 filters at 31 WTPs operated by K-water, the evaluation of filtration performance and the investigation of major causes related to particle breakthrough were explored. 98.1 % of the filters had an effluent turbidity measurement which was less than 0.1 NTU, but turbidity breakthrough of more than 0.3 NTU was noticed occasionally which is in violation of AWWA 5-Star guidelines. It was shown that the optimization of coagulation, filter-to-waste, the observance of optimal filtration velocity and backwashing process based on filtrate turbidity were crucial for the improvement of filtrate.

• Journal of Korean Vacuum Science & Technology
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• v.6 no.3
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• pp.120-125
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• 2002

The aim of the present work is to optimized the annealing parameter in both front and back screen printed contacts realization on p-type multicrystalline silicon and with phosphorus diffused. The RTA treatments were carried out at various temperatures from 600 to 850$\^{C}$ and annealing time ranging from 3 min to 5 min in air, O$_2$and N$_2$ ambiance. The contacts parameters are obtained according to Transmission Line Model measurements. A good RTA cycle is obtained with a temperature plateau of 700$\^{C}$-750$\^{C}$ and annealing ambiance of air. Several processing parameters required for good cell efficiency are discussed with an emphasis placed on the critical role of the glass frit in the aluminum paste. A anamolus behaviour of Aluminum n-doping on p-type Si wafer, contact at high temperature have also been studied.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.129-134
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• 1999

Recent construction activities and maintenance of marine facilities have been accelerating to keep up with rapid economic growth in Korea. Marine concrete structures are to salts and chloride from ocean environments. The corrosion of reinforcement steel caused by chloride-penetration into concrete may severely affect the durability of concrete structures. the objective of this research is to develop a durable concrete by investigating the resistance of various corrosion protection systems utilizing different water/cement ratio, silica fumes, corrosion inhibitors, etc. A two-year verification test on various corrosion protection system has been doing in the laboratory. Corrosion investigations on reinforcement steel are now under progress for more than 63 concrete specimen. Corrosion-related measurements include microcell corrosion current.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.8
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• pp.841-848
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• 2008

Based on the averaged Korean head shapes that are the results of digital Korean project by KISTI and Catholic university, experimental apparatus of head dummies of Korean male and female are developed in order to measure head-related transfer functions(HRTF) by using a reverse engineering and rapid prototyping techniques. For the Korean dummies, HRTFs are measured using the substitution method ever 12kHz frequency bands. At every azimuth angle $15^{\circ}$ HRTFs are measured for elevation angles $-30^{\circ}$, $0^{\circ}$ and $-30^{\circ}$. The measured HRTFs are compared with those of KEMAR(knowles electronic manikin for acoustic research) dummy head, which shows $3{\sim}5\;dB$ difference over $4{\sim}5\;kHz$ kHz frequency band.