• Ocean and Polar Research
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• v.26 no.3
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• pp.481-486
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• 2004

A portable apparatus mounting Acoustic Doppler Current Profilers (ADCP) to any small boat was developed to effectively measure currents in shallow and narrow coastal seas like the west coasts of Korea. Characteristics of the apparatus is that an underwater fish-shaped body protecting an ADCP is designed to reduce the drag during the cruise, which can be freely mounted and detached from a boat with a clamp. Several cruise outputs prove themselves that the apparatus is properly designed for the intended purpose, to minimize air bubbles and to control the submerged depth of the sensor.

• Progress in Superconductivity and Cryogenics
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• v.14 no.2
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• pp.32-35
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• 2012

The objective of the present work is to develop a precise instrument for measuring the thermal property of insulating material over a temperature range from 30 K to near room temperature by utilizing a cryocooler. The instrument consists of two thermal links, a test sample, heat sink, heat source and vacuum vessel. The cold head of the cryocooler as a heat sink is thermally anchored to the thermal link and used to bring the apparatus to a desired temperature in a vacuum chamber. An electric heater as a heat source is placed in the middle of test sample for generating uniform heat flux. The entire apparatus is covered by thermal shields and wrapped in multi-layer insulation to minimize thermal radiation in a vacuum chamber. For a supplied heat flux the temperature distribution in the insulating material is measured in steady and transient state. The thermal conductivity of insulating material is measured from temperature difference for a given heat flux. In addition, the specific heat of insulating material is obtained by solving one-dimensional heat diffusion equation.

• Journal of Korea Multimedia Society
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• v.18 no.12
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• pp.1427-1431
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• 2015

In the salvage area, the location of the incident vessel and diver to rescue the victim are very important. But there are no ways but to rely on the GPS satellites to obtain the location in the salvage sites. Because the positioning using GPS satellites has a measurement error of up to 50 meters caused by the status of the atmosphere, a new positioning method with more accuracy should be devised. So if studies on measuring the position of the ships and divers accurately in the sea are performed, it will be helpful in the field of the salvage positioning. In this paper, a high precision positioning system in salvage using DGPS signal through mobile broadcasting is proposed with positioning error of up to 1 meter.

• Journal of the Korean Institute of Navigation
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• v.20 no.3
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• pp.31-42
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• 1996

It is important to investigate the hull response of a fishing vessel in waves to ensure the safety of it and to keep excellent sea-keeping qualities. For this purpose, we measured the response of fishing vessels in waves using real sea experimental measuring system. We analyze the experimental data by statistical method and spectral analysis to get the characteristics of the response of vessels which have different tonnage. In this real sea experiment, we use three stern trawlers which are the training ship in university. We know that the distribution of experimental response have Gauss distribution and Rayleigh distribution and smaller vessels have larger response.

• Journal of the Korean Vacuum Society
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• v.11 no.2
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• pp.81-86
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• 2002

With a specific model for the Helicoflex type metal gasket expected to be used in large ports of the KSTAR vacuum vessel, a sealing curve was obtained by measuring the flange tightening properties such as the correlations of the tightening torque(or linear load), displacement to the leak rate. From the experiment results it was found that the leak rate of the Helicoflex seal in the room temperature was bellow $2\times10^{-1}\textrm{mbar\cdot L/s}$ with a tightening torque of 2500kgf . cm using Ml8 bolts.

• Journal of Magnetics
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• v.18 no.2
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• pp.188-191
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• 2013

The magnetic properties for sanal's mobility inside of the lymphatic primo vascular system, the so-called Kyungrak (or meridian) system, are investigated under a low static magnetic field with the anatomy technology and optical microscope. One sanal with a size of 1 ${\mu}m$ under microscope selected and separated from the primo vessels of the primo vascular system are observed in rabbits' lymphatic vessels around abdominal aorta and placed in PBS solution with petridish. The moving displacement of sanal versus the measuring time of 20 Oe below a magnetic field of 80 Oe is stronger in dominanting dependence according to the x-direction than y-direction.

• Journal of Biomedical Engineering Research
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• v.10 no.1
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• pp.25-32
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• 1989

In this study, Rheoencephalography( REG ) was designed and constructed. Using the cons- tructed instrument cerebral blood flow(CBF) of left and right brain, CBF change by posture, and reproducibility were studied. Followings are important results. Relative CBF could be measured noninvasively and continuously. Since reproducibility of the constructed REG was found to be quite high (4%), the accuracy of the instrument itself was proved. REG can be easily applied for testing the effect of drugs for the patients with cerebral vessel diseases since it is quite sensitive to the relative changes of CBF. Various cerebral diseases can be diagnosed by analyzing the REG waveforms. The area of restricted cerebral blood vessels can be located by arranging the electrode configuration. Comparative studies with the standard techinques of measuring CBF are needed to verify the accuracy of REG. Further studies on optimal electrode configuration and various artifacts are also necessary.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.8
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• pp.720-727
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• 2004

In the process of ice-slurry making, the phenomenon of ice adhesion influences extremely to ice making system. In this study, the effect on the ice adhesion by thermal storage material with additives is investigated quantitatively. Various solutions of 300 g in a stainless vessel were frozen under stirring. Through the experiment the ice adhesion between cooling wall and ice-slurry was compared with each other by measuring the stirring power. From the experiment, the stirring power in EG, SCA solution was smaller than those in the solution containing functional materials, such as poly-vinyl-alcohol or kitchen detergent.

• Journal of Chest Surgery
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• v.22 no.5
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• pp.845-850
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• 1989

Intralobar pulmonary sequestration is rare congenital lung disease characterized by a cystic portion of the lung that derives its arterial blood supply though aberrant vessel directly of systemic circulation. Intralobar pulmonary sequestration is usually contained within the visceral pleura of a pulmonary lobe and its venous drainage to the pulmonary venous system. We experienced a case of pulmonary sequestration postoperatively confirmed. The patient was 48-year-old female whose complaints were cough and left chest pain. Chest film showed large homogenous opacity in left lower lung field. By operation, adult fist sized mass at the lower lobe were noted. An aberrant artery, measuring 1.0 cm. in diameter and 2.0 cm. in length, arose from the descending thoracic aorta just above the diaphragm. The anomalous systemic artery was ligatures and resection, and associated with left middle, lower bilobectomy was done. The postoperative course was uneventful, and 10 days later discharged.

• Journal of Fisheries and Marine Sciences Education
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• v.12 no.2
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• pp.199-212
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• 2000

It is very important to investigate the hull response of a fishing vessel in the sea to ensure the safe navigation and fishing operation in rough sea by preserving excellent sea keeping qualities. For this purpose, the author measured various responses of three stem trawlers in waves using real sea experimental measuring system. The author analyzed the experimental data using the statistical and spectral analyzing method to get the characteristics of the motion responses of the vessels according to the wave height and the ship's speed. The results obtained can be summarized as follows ; (1) Rather higher response of the pitch motion due to the wave height appeared in the head sea and the bow sea than any other wave direction without relevance to ship's size. In case of the roll motion, the beam sea and the quartering sea have a high response value. The period of peak of the pitch motion and the roll motion according to the wave height in each vessel has almost same value respectively. (2) The change of response of the pitch motions deeply depend on the ship's speed in the head sea and the bow sea, but not in the other wave direction. (3) The change of response of the roll motions in the beam sea, the quartering sea and the following sea are affected by the influence of the ship's speed in 5k't to 8k't, but not related to the ship's speed in out of that range.