• Proceedings of the Korea Association of Crystal Growth Conference
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• 1997.06a
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• pp.187-196
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• 1997

Oxygen transfer in silicon melts during crystal growth under vertical magnetic fields is investigated numeriaclly and experimentally. A three-dimensional numerical simulation, including melt convection and oxygen transport, is carried out to understand how oxygen transfers in the melt under magnetic fields. Oxygen concentrations in single silicon crystals grown from the melt under these magnetic fields are experimentally measured by using an infrared absoption technique. The rusults obtained are compared to results from a numerical simualtion. An anomalous increase is observed in the oxygen concentration of the grown crystals under a magnetic field of about 0/03 tesla. The cause of this anomaly is identified as Benard instability, since the temperature at the bottom of the crucible is higher than that at interface. When the temperature at the bottom is decreased, the Benard cell can be removed, and a monotonical decrease in the oxygen concentration in the single crystals can be observed.

• Journal of Environmental Science International
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• v.8 no.3
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• pp.293-297
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• 1999

Based on the monthly weather report of Korea Meteorological Administration (KMA) and daily sea surface temperature (SST) in Incheon harbor of National Fisheries Research and Development Institute, heat budget in Incheon coastal area was estimated. The temperature differences between the sea surface and near bottom were nearly within 1$^{\circ}C$. This indicate the mixing from the sea surface and the bottom. The net heat flux through the sea surface and the advection through the inner and outer bay was affected uniformly to the water body in Incheon coastal area. The net heat flux was about 110W/$m^2$ in maximum value on May, about -80W/$m^2$ in minimum on January. The net heat flux through the sea surface from the solar radiation was about 2.35$\times$${10}^5$W during the year. This heat flux flew out the bay through the advection by the same flux.

• Journal of Food Hygiene and Safety
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• v.10 no.2
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• pp.53-59
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• 1995

Vibrio unlnificus, a normal inhabitant in estuaries, is of great concern because it is a potent human pathogen causing septicemia, wound infection and gastrointestinal disease in Kum river, sampling was undertaken in five station from March, 26, 1993 to February, 22, 1994. Samples of 54 and 49 were collected from seawater and bottom deposit. The total detection rate of V. unlnificus was 11.7%. The detection rates of V. unlnificus in the seawater and the bottom deposit were 9.3% and 14.3% respectively. V. unlnificus was mainly detected in estuary water when temperature was above 23$^{\circ}C$ and salinity was below 15%. We suppose that water when temperature, salinity, pH and COD affect growth of V. unlnificus.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.22 no.3
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• pp.1-7
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• 1986

This is a basic study of further investigating the effect of oceanographic conditons, such as bottom profile, currents, and temperature, to the fish migrating course around the set-net. The survey was held at Dojang Po, southern part of Geoje Island, from July to October in 1985. There was a sea valley of which depth was 20 to 40 meters around the set-net. Near the bottom of that sea valley, there was different current pattern to the upper layer. In the sea calm condition of July and October, the vertical profiles of current and water temperature were simple. But in rough condition of September, they were complicated because of wind tuburance.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.6
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• pp.1151-1156
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• 2009

Unstable sustain discharges can occur at the bottom cells of the panel at high temperature. To solve this problem, the wall charge variation during an address period was investigated. A test panel of 7.5 inch XGA level was used and one green cell was measured. In order to realize operating condition equal to that of the bottom cells of 50 inch panel, the addressing stress pulses are applied. It seems that the resultant wall charge loss during address period increased with increase of stress time, temperature, pressure and Xe %. Wall charge loss increases with potential difference between scan electrode and address electrode, therefore wall charge loss can be minimized by the increase of scan voltage during address period.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.264-267
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• 2004

[ $Bi_{3.25}La_{0.75}Ti_3O_{12}$ ] (BLT) thin films were prepared by using metal organic decomposition method onto the $LaNiO_3$ (LNO) bottom electrode. Both the structure and morphology of the films were analyzed by x-ray diffraction (XRD) and atomic force microscope (AFM). Even at low temperatures ranging from 450 to $650^{\circ}C$, the BLT thinfilms were successfully deposited on LNO bottom electrode and exhibited (117) orientation. The BLT thin films annealed as low as $600^{\circ}C$ showed excellent ferroelectricity, higher remanent polarization and no significant degradation of switching charge at least up to $5{\times}10^9$ switching cycles at a frequency of 100 kHz and 5 V. For the annealing temperature of $600^{\circ}C$, the remanent polarization Pr and coercive field were $23.5\;C/cm^2$ and 120 kV/cm, respectively.

• Journal of Environmental Health Sciences
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• v.14 no.1
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• pp.47-53
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• 1988

This study was performed to investigate a seasonal and vertical variation of the nutrients, water temperature, pH, DO, BOD, COD in Sukchon lake from May 1985 to Jan. 1986. The results were as follows. 1. Vertical descent of water temperature was the remarkable situation on Jul. and difference between surface layer and bottom layer was 3.5$\circ$C. 2. The value of pH was average 8.0 in both lake. The value of pH in the winter was average 7.6, and Summer was average 8.3. 3. The contents of dissolved oxygen was the highest value (13.0mg/l in surface layer on Jan. and the lowest value (8.1mg/l in bottom layer on Ul. 4. The contents of PO$_4$-P, NH$_3$-N, NO$_3$-N and T-N were 0.03~O.17mg/l 0.12~0.34mg/l 0.36~0.91mg/l and 0.76~1.37mg/l respectively.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1609-1614
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• 2003

In this study, a practical holographic interferometric tomography system, which is instantaneous and non-contact for measuring three dimensional flow field, was developed. The system consists of holographic recording/reconstruction system, fringe analysis code and computational tomography code and it is developed with Gill environment for general users. The developed system was applied to three-dimensional natural convection from a discrete flush-mounted circular heat source on the bottom of a cubic enclosure. The heat source was located at the off-center of the bottom plate so that three-dimensional temperature field can be achieved. A set of multi-directional holographic interferograms was recorded by employing a double-reference beam, double-exposure holographic technique. Optical pathlength data were extracted from the recorded interferometric data and finally three dimensional temperature field inside the cube was reconstructed.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.291-296
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• 2000

The crack of concrete induced by the heat of hydration is s serious problem, particularly in concrete structures such as bridge piers. thick walls, box type walls, mat-slab of nuclear reactor building, dams of foundations of high rise buildings, etc. As a result of the temperature rise and restriction condition of foundation, the thermal stress which way induce the cracks can occur. Therefore the various techniques of the thermal stress control in massive concrete have been widely used. One of them is prediction of the thermal stress, besides low-heat cement which mitigates the temperature rise, design change which consider steel bar reinforcement, operation control and so on. In this study, firstly it introduce the thermal cracks control technique by employing low-heat cement concrete, thermal stress analysis, Secondly it shows the application of the cracks control technique like the bottom of No.15,16 Underground LNG Tank in Inchon.

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.2001-2003
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• 1996

In this study, Allied Signal 211 SOG was used as a sacrificial material. After researching its etching properties, we adapted it to bottom-drive micrometers. SOG was superior etch rate and roughness to them of PSG or CVD-oxide and possible to low-temperature processing. Etching properties of SOG depended on the temperature and duration of its bake and cure. SOG used in the fabrication of bottom-drive micrometers showed us usefulness as a sacrificial layer and haying a least influence on machines on it in comparison with conventional sacrificial materials.