• Journal of Magnetics
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• v.2 no.1
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• pp.16-21
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• 1997

Those were investigated, the crystallographic, morphological, and magnetic properties of barium ferrite film (SiO2/Si substrate) prepared by sol-gel dip coating. Appropriate sol was prepared by dissolvin barium and iron nitrate in ethylene glycol at 80$^{\circ}C$. To obtain the films, thermally oxidized p-type silicon substrate with (111) of crystallographic orientation were dipped into the sol, dried at 250$^{\circ}C$ to remove organic material, and heated at 800$^{\circ}C$ for 3 hours in air for the crystallization of barium ferrite. It was found that the particles of barium ferrite formed on the substrate exhibited needle-like shape placing parallel to the substrate and its c-axis is long axis direction. There was tendency that the coercive force in horizontal direction to the substrate was higher than that in vertical direction to it. This tendency was profound in large thickness.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.06a
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• pp.45-52
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• 2003

Construction and extension of road by industrialization are increasing. According to this, construction of large cutting slope is increasing. Therefore, many methods for slope stability by this are applied. Failure happens according to dip and dip direction of slope. It is actuality that is connoting unstable element. This slope include coaly shale. Stability of slope failure this study takes place by road extension running examination for stability property calculate. Use this and examined stability about stereographic projection and wedge failure. Apply suitable reinforcement countermeasure about unstable cutting slope and analyzed stability. Wish to consider effective and robust processing plan of great principle earth and sand side securing stability. Hereafter with these data, is going to utilize in reinforcement and failure prevention.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.369-370
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• 2002

To clarify the tribological properties of biodegradable lubricating oils, the four-ball tests were carried out under dip-feed lubrication using a Soda-type four-ball machine. The test balls were lubricated with soybean oil, rapeseed oil, corn oil and turbine oil. From the tests, the coefficient of friction for all the test balls lubricated with biodegradable lubricating oils was lower than that for the test ball lubricated with turbine oil. Further, from the calculation of the pV value, it was clear that the seizure resistance for all the test balls lubricated with biodegradable lubricating oils was higher than that for the test ball lubricated with turbine oil.

• Parasites, Hosts and Diseases
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• v.38 no.1
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• pp.37-39
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• 2000

Many Koreans usually eat raw pond smelts, Hypomesus olidus, in the winter. This study was performed to evaluate the infection status with trematode metacercariae in pond smelts from January 1998 through February 1999. Among 1,305 fish collected, 459 were purchased from wholesale dealers in Chinchon-gun, Chungchongbuk-do, and the rest of them were caught with a casting net in Soyangho (Lake), Taehoman (Bay) and Paekkokchosuchi(Pond). Seven species of trematode metacercariae including two unidentified ones were detected from 1,305 pond smelts. The number of detected trematode metacercariae according to the species are as follow: Clonorchis sinensis 8, Holostephanus nipponicus 7, Cyathocotvle orientalis 24, DipLostomum sp. 14, and Metorchis orientalis 7. From the above results, it was confirmed that H. olidus plays a role as the second intermediate host of some kinds of trematode including C. sinensis in Korea. Our report shows possible clonorchiasis caused by eating raw pond smelts.

• Proceedings of the IEEK Conference
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• 2000.06a
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• pp.260-262
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• 2000

Printed microstrip antennas are known to have limitations in terms of bandwidth by the presence of the dielectric substrate. In this paper, to overcome these limitations, a broadband microstrip bow-tie antenna which has two dip point for high speed wireless LAN, fabricated on a Taconic substrate is designed and simulated. In simualted results, the return loss is two dip point which is -28.5dB at 5.68GHz and -27dB at 5.85GHz. The bandwidth of this antenna is 8.7％ about VSWR$\leq$2 and 5.9％ about VSWR$\leq$1.5.

• Journal of the Korean Ceramic Society
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• v.52 no.4
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• pp.234-236
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• 2015

$Y_2O_3$-SiC composite membrane was dip-coated using $Y_2O_3$ sol solution; this membrane was compared with a non- coated one. Each membrane was characterized by XRD, FE-SEM and BET techniques. Hydrogen and CO permeation were tested with self-manufactured Sievert's type equipment. $Y_2O_3$ coating was enhanced for the selectivity of the membrane ($H_2$ versus CO). The hydrogen permeation was measured at 1 bar with increasing temperatures. In case of the coated membrane, hydrogen permeation was found to be $1.24{\times}10^{-7}mol/m^2sPa$ with perm-selectivity of 4.26 at 323 K.

• Proceedings of the Optical Society of Korea Conference
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• 2009.02a
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• pp.427-428
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• 2009

Optical imaging offers excellent spatio-temporal sensitivity that is unparalleled by any other perfusion based imaging techniques. We used in vivo optical recording of intrinsic signals (ORIS) to map neurovascular hemodynamics of perfusion, oximetry and membrane potential during epileptic events in rat and mouse neocortex. Studies of hemodynamic changes with ORIS alone were also performed in human. Laboratory studies in rodent epilepsy models have demonstrated a persistent increase in deoxygenated hemoglobin (Hbr) and a decrease in tissue oxygenation during interictal spikes and ictal events. This "epileptic dip", like the "initial dip" recorded during normal sensory processing, implies that the enormous rise in cerebral blood flow (CBF) is inadequate to meet the increased metabolic demands associated with synchronized epileptic activity. These findings are critically important to the interpretation of the perfusion-based imaging studies, such as fMRI. In addition, we visualized the effect of direct cortical electrical stimulation, an alterative epilepsy treatment. The optical data following direct cortical electrical stimulation showed that hemodynamic signals are sensitive to different electrical stimulation parameters. Furthermore, our recent data demonstrated that the application of unilateral electrical stimulation is able to elicit bilateral hemodynamic responses in rat neocortex.

• Korean Journal of Optics and Photonics
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• v.4 no.2
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• pp.212-219
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• 1993

To reduce the mode noise induced from a multimode dye laser, a modeless laser generating amplified spontaneous emission was used as Stokes beam of the broadband CARS. A new technique for measuring species concentration from the modulation dip of nonresonant background of broadband CARS spectrum was proposed. The modulation dip was numerically calculated and fitted as a function of the concentration of the minor species and temperature of gas sample. We applied this technique in measuring CO concentration in a static cell and also the profile of CO concentration in a CHdair premixed flame of a counterflow burner.

• Journal of the Korean institute of surface engineering
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• v.28 no.5
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• pp.300-308
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• 1995

The effect of nitrogen finishing for the control of coating weight in a nitrogen sealing box on the coating surface property in hot dip galvanizing process has been studied. The coated surface is free of oxide marks and edge overcoated. The coating uniformity is excellent ; the standard deviation of the coating thickness along width of the specimen was $1~1.2\mu\textrm{m}$ in the box whereas $2.5~3\mu\textrm{m}$ in the air. Considering surface quality of the coating such as oxide mark, edge overcoated and zinc dust, the oxygen content between 40 and 200 ppm was suggested in the box in addition the oxygen content of at least 40 ppm or the minimum dew point of $-27^{\circ}C$ is required to prevent a zinc vaporization.

• Journal of the Korean Ceramic Society
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• v.29 no.12
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• pp.970-980
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• 1992

${\gamma}-alumina$ membranes were prepared by sol-gel dip coating or pressurized coating of boehmite sols on slipcasted ${\gamma}-alumina$ support tubes. The particle size of sols synthesized via the modified Yoldas-method could be controlled below 5 mn according to the mole ratio of nitric acid/aluminumtri-sec-butoxide (0.07~1.0). The reproducible crack-free composite membranes were produced by the 2nd dip coating or the pressurized coating technique using very stable sols with the particle size of 45 nm. Nitrogen gas permeability through the top-layer in the composite membrane was about $70~55{\times}10^{-7}\;mol/m^2{\cdot}s{\cdot}Pa$. The thermal stability of the top layer was proved to be good enough upto the heat-treatment temperature of $500^{\circ}C$.