• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.2
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• pp.225-238
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• 1997

Zooplankton distribution in the front zone was investigated in the East Sea of Korea (Sea of Japan). More than 100 taxa appeared in the study area, which was far diverse appearance being compared with those in West (Yellow Sea) and South Sea of Korea. In Nov. 1994, Paracalanus parvus, Oikopleura spp., and Noctiluca scintillans, which preferred warmer environment, predominated at the collection sites in the front zone, especially at warmer surface layer. But in Nov. 1995, when the surface water temperatures were about $2^{\circ}C$ lower than those of the previous year, cold water species of copepod Metridia lucens, immature forms of Calanus and Sagitta, and crustacean eggs dominated in the collection sites in front zone, which were geographically not Identical with those of the previous year. Vertical distributional patterns were not coincide among the taxa. This suggests that zooplankton has different specific habitat characteristics with temperatures. In general, those taxa with preference of warmer environments showed high probability of co-occurrance with low abundances while those that preferring colder environments showed low probability of co-occurrance with high abundances. It seems that warm water contributes to the high diversity of zooplankton in the front zone while cold water does to the high biomass.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.8 no.3
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• pp.121-126
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• 1975

Chlorophyll a content in marine phytoplankton and nutrient in seawater were determined to study the influence of eutrophication of Jinhae Bay area on primary production. Sampels were taken in the surface layer and bottom of 21 stations in Jinhae Bay including Masan Bay and Hengam Bay, ana adjacent waters such as Geoje Bay and the estuary of Naktong River for refrence during summer Period in 1974. Chlorophyll a content was ranged from $0.52\;mg/m^3\;to\;25.16\;mg/m^3$ in whole area. Mean value of chlorophyll a was the highest in Masan Bay and the lowest in GeojeBay. It was noteworthy that chlorophyll a content of Hengam Bay was not much higher than that of neighboring ares and rather lower than that of the estuary of Naktong River in spite of high phosphate content. Linear relationship between increase of nutrients and chlorophyll a was found in Masan Bay and the estuary of Naktong River where N/P ratio of nutrients was over 12. This relationship however could not be found in most area of Jinhae Bay where N/P ratio of nutrients was lower than 2 which might due to the wastewater from the Chemical Fertilizer plant. Red tide and low dissolved oxygen waters due to eutrophication were observed during summer period in Masan Bay.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.1
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• pp.545-551
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• 2011

Recently, demands for generating high quality tap waters are increasing with high concern of water pollution and corrosion of water pipelines. For the reasons, developing water quality stabilization technique in water purification system is sought rather than replacing to a new pipelines. In this study, high-purity liquid lime($Ca(OH)_2$) was introduced for a water quality stabilization technique in water purification process and simulated water distribution system of pilot-scale size was applied to evaluate anti-corrosion control effect. The effect of anti-corrosion control was calculated in terms of LSI(Langelier Saturation Index) In conclusion, the result of pilot plant showed improvement of corrosiveness by liquid lime($Ca(OH)_2$) with reduction of released iron(Fe). Application of anti-corrosion control technique to the mild steel coupon and the copper coupon were effective by indicating 35.4, 44.5% of improvements. Besides, sample pipes which were treated with liquid lime had formated more thicker layer of corrosion product inside of pipes. As a result, the process of injecting water stabilizer can greatly contribute to the high quality of tap water.

• Journal of Conservation Science
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• v.27 no.2
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• pp.223-229
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• 2011

Buddha painting cultural properties couldn't avoid the change of colors and the exfoliation phenomenon by the characteristic of material and environmental factors. Especially, because in the beginning of the fine crack and the decoloration phenomenon on the surface of pigment would be significantly decrease stability of the whole object, it is necessary to take particular measure. Therefore, this is a study on conservation of Avalokitesvara in Potalaka in Hyeondeungsa in Gapyeong. It treated damaged parts of the object, carried out backing papers and matching colors. And then, it examined scientific analysis of pigments. Also, it performed nondestructive testing like XRF, FT-IR, and image microscope to investigate the quality of the material of hanji using the object and the component and characteristic of pigments. As a result, FT-IR spectrum matching Korean traditional paper(hanji) was detected in hanji of Avalokitesvara in Potalaka in Hyeondeungsa. The black pigment making a thin layer over the white pigment would estimate carbon compounds of unconfirmed ink stick or soot as XRF and FT-IR. Also, the white pigment was lead white($PbCO_3{\cdot}Pb(OH)_2$) involving Pb(Lead) and a carbonate. It was observed that the crystal of blue pigment had the different sizes of the particles from the microscope. In the case of this blue pigment, it showed cobalt blue and lead white was mixed when it used because both Cu and Pb were highly detected in XRF data.

• Journal of Conservation Science
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• v.31 no.4
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• pp.499-506
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• 2015

The artifacts of Admiral Yi Sun-sin (Treasure No.326) consist of six items with two long swords, a jade decoration, a belt and two peach-shaped cups. In commemoration of the opening of Chungmugong Yi sun-sin Memorial Museum (April 28, 2011), there were conservation treatments for those artifacts at the beginning of 2011. At that time, from the result of non-destructive surface analysis on pigments in blood-colored grooves of the two long swords, it was presumed to be synthetic resin paints. This study shows the accurate identification on pigments which was presumed as synthetic resin paints and its removal. To identify pigments in blood-colored grooves, the optical microscope, scanning electron microscope, Micro-XRF, XRD and FT-IR were used for the analysis. The results turned out that the thickness of $10{\sim}90{\mu}m$ in a single layer was measured. And major components containing Pb and Cr and lead chromium molybdenum oxide were identified and to identify components of adhesives from the analysis by FT-IR, it turned out to be alkyd resin, which can be presumed that they were recently colored with synthetic paints. The synthetic paints easily react with most of the organic solvents. And it is so easy to handle without the effect on metal that it was removed with acetone. While removing synthetic paints, all of paints on it were collected for identifying whether there is traditional pigment but nothing was identified.

• Journal of KIISE:Information Networking
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• v.35 no.1
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• pp.46-55
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• 2008

As a mobility support for IP have studied, Internet Engineering Task Force(IETF) standardized the Mobile IPv6(MIPv6) protocol. When a mobile node moves between subnets, MIPv6 maintains connectivity to network and supports seamless communication, and these processes are called a Handover. Whenever the mobile node moves between subnets, the Handover is performed. The mobile node can not communicate during the Handover. This period is Galled Handover latency. To reduce this latency, mipshop working group standardizes Fast Handovers for Mobile IPv6(FMIPv6), but latency which the mobile node registers its new care-of address to a home agent and a correspondent node is still long. To solve this problem, we propose a scheme that the mobile node registers the new care-of address to the home agent and initiates Return Routability procedure in advance during layer 2 handover, based on FMIPv6 and IEEE 802.11. We analyze MIPv6, FMIPv6 and the proposed scheme in term of packet transmission cost during the Handover. Compared to MIPv6 the proposed scheme gains 79% improvement, while it gains 31% improvement compared to FMIPv6.

• 한국초전도학회:학술대회논문집
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• v.9
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• pp.343-347
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• 1999

We fabricated a resistive SFCL having a shunt resistor parallel to it in order to bifurcate the transient current at faults. The SFCL consists of a YBCO film coated with an Au layer (10 ${\omega}$ at room temperature), which is to disperse the heat generated at hot spots in the YBCO film, and the 5 ${\omega}$ shunt resistor. The minimum quench current of the SFCL was found to be 12.2 A$_{peak}$. This SFCL successfully controlled the fault current below 23 A$_{peak}$ which is otherwise to increase up to 113 A$_{peak}$. Bifurcation of the current resulted in the temperature rise of the YBCO/Au film 3 times slower than without the shunt, protecting the SFCL at high currents.

• The Korean Journal of Mycology
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• v.2 no.1
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• pp.7-14
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• 1974

These experiments were conducted to learn the antibiosis of microfloral organisms in the casing soil to Mycogone perniciosa, and interactions between M. perniciosa and Agaricus bisporus. The results obtained were as follows: 1. In vitro tests, the development of M. perniciosa was suppressed from the unidentified microfloral organisms in the casing soil. All the infected sporophores of A. bisporus occurred within an area applied with spore suspension of M. perniciosa as spot treatment and no infected ones in the area around the spot treated under cropping conditions. 2. In vitro tests, although the antagonistic relationship between M. perniciosa and A. bisporus was somewhat different in varying the kind of media, A. bisporus ultimately overgrew the colony of M. perniciosa. When spore inoculation of M. perniciosa was applied on the surface of grain spawn of A. bisporus and the mid layer of casing soil under cropping conditions, no infected sporophores were produced, whereas the infected sporophores were only produced on casing soil inoculated on the surface of casing soil with spore suspension.

• Journal of Sericultural and Entomological Science
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• v.15 no.2
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• pp.35-43
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• 1973

Since automatic silk reeling machine has been used in the fold, silk reeling tension has been considered to be an important matter. Such silk reeling tension affects on the physical nature of silk which would be Wire Silk in case of super high reeling velocity. This will be a report regarding with the silk reeling tension used Korean cocoon and various analyses are carried out where reached to following results. 1. Korean silk is still far from Wire Silk yet produced as general silk. 2. There is more possibility to increase silk reeling velocity if cocoon nature is improved. 3. At present, it is considered that the optimum reeling velocity is to be about 190 r.p.m. which is corresponded with 0.4∼0.5 g/d silk reeling tension. 4. This report has prepared a silk reeling tension contolling diagram against reeling velocity as shown at Figure 7. The mathematical relations between them are; A. in case of total silk reeling tension; Y=5.0831＋0.0381X(Y; total reeling tension, g/21d, X; reeling velocity, m/min) B. in case of initial silk reeling tension; Y=3.1922＋0.0175X (Y; initial reeling tension, g/21d, X; reeling velocity, m/min) 5. The main problems for the increase of silk reeling velocity is considered to be Break Down of Silk Reeling Ends caused by Cocoon Jumping or Cocoon Layer Seperation during the silk reeling work. Such troubles are concerned with the produced cocoon nature.

• Membrane Journal
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• v.26 no.4
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• pp.239-252
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• 2016

Two-dimensional materials offer unique characteristics for membrane applications to water technology. With its atomic thickness, availability and stackability, graphene in particular is attracting attention in the research and industrial communities. Here, we present a brief overview of the recent research activities in this rising topic with bringing two membrane architecture into focus. Pristine graphene in single- and polycrystallinity poses a unique diffusion barrier property for most of chemical species at broad ambient conditions. If well designed and controlled, physical and chemical perforation can turn this barrier layer to a thinnest feasible membrane that permits ultimate permeation at given pore sizes. For subcontinuum pores, both molecular dynamics simulations and experiments predict potential salt rejection to envisage a seawater desalination application. Another novel membrane architecture is a stack of individual layers of 2D materials. When graphene-based platelets are chemically modified and stacked, the interplanar spacing forms a narrow transport pathway capable of separation of solvated ions from pure water. Bearing unbeknownst permeance and selectivity, both membrane architecture - ultrathin porous graphene and stacked platelets - offer a promising prospect for new extraordinary membranes for water technology applications.