• Applied Chemistry for Engineering
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• v.24 no.5
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• pp.456-470
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• 2013

Hollow-fiber membranes, is one of the new technologies that is growing rapidly in the past few decades. In addition, separation membranes using polymer materials, have attracted attentions in various fields including gas separation, fuel cells, water treatment, wastewater treatment, and organic separation. Nanofiltration (NF) membranes having the separation characteristics in the intermediate range between ultrafiltration and reverse osmosis (RO) membranes for liquid separation, with relatively low investment cost and operating pressure lower than that of RO membranes, have high permeance and rejection performance of multivalent ions as well as organic compounds of molecular weight between $200{\sim}1000gmol^{-1}$. In this paper, we would like to review the research trends on the various structure control and characterization of NF hollow fiber membranes with respect to materials and the methods of preparation (phase inversion method and interfacial polymerization method). Currently, most of NF membranes have been manufactured by plate and frame types or spiral wound types. But hollow fiber types have delayed in commercial products, because of the weak strength when to produce on the basis of the existing materials, therefore the development of new materials or improvement of existing materials will be needed. If improving manufacturing technology is available, hollow fiber types will replace spiral wound types and gradually show a higher market share.

• Korean Journal of Plant Resources
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• v.18 no.3
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• pp.512-517
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• 2005

To establish the economical cultivation method of Gastrodia elata Blume by controlling the shading rate and the mixing ratio of recycling spawn bed logs, a serial experiment was carried out. When G. elata was grown in the field with no shading, the yield of spawn tuber was higher than that of tuber of G. elata. The yield of G. elata was high in the rainproof green house covered with one layer of $95\%$ shading net, in the rainproof green house covered with two layers of $95\%$ shading net, and in the field with no shading, in that order. In the case of mixing ratio of recycling spawn bed logs, the yield was high in the fresh logs, in the mixing ratio of 2:1, and the ratio of 1:1, in that order. The income of the rainproof green house covered with one layer of $ 95\%$ shading net which brought the best yield was $81\%$ in the mixing ratio of 2:1 over the fresh logs.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.5
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• pp.49-58
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• 2010

The traffic signal controllers being used in the domestic currently are being manufactured based on the korean national police standard which was developed for controlling the quad-light traffic signal having the red, yellow, left-turn arrow, and green lights. But according to the national policy for the traffic operation, they have to be changed to be able to switch the tri-light signal having red, yellow and green lights. In this study, a new tri-light traffic signal controller was designed and developed by the way improving the Signal Control Unit of the existing quad-light standard traffic controller. The Load Signal Unit(LSU) was improved to output 6 signals which are the two assemblies of three signal indications having the red, yellow, and green lights. To enough traffic signals output to control each directional movements and the various transport modes which are car, bus, bike, and pedestrian etc., the connector bus system was designed to be able to accommodate maximum 96 signals outputs being constructed by 16 LSUs. Flasher device was developed to be able to support maximum 32 red signals. In the software, the communication protocol between traffic control center and the traffic signal controller was improved and new signal map code values were defined for the developed LSU controlling the quad-light traffic signal. A model of the quad-light traffic signal controller developed and was tested three operations, protocol-operation, remote-command and control-mode. The test result operated all of them successfully.

• Journal of the Korean Society of Costume
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• v.4
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• pp.13-24
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• 1981

The color yellow was considered from ancient time to the Chosun Dynasty as the central color. Thus, this color became the royal color for the costumes in the palace. It is generally known to usthat the color yellow was controled in use both for the general public and in the royal palaces. However, in the later part of Chosun Dynasty, the color yellow was used not only for the king's costumes but also used for women's tops and for the linings of clothing. Especially, in some of the costumes that belonged to the later period of the Chosun Dynasty, we can still see lots of bright yellow tops. Also there are many green dyed official robes and various costumes for women. It is a true fact that people could not derive the color green from the plants as they did with yellow. The only way they could make the color green was to mix indigo and yellow together. By repeating the difficult process of making various dyes constantly during many centuries, the Korean people developed the marvelous technique of making natural color. Those plants used to make the color yellow are ; Gardenia, Phellodendron amurense, Turmeric, Coptis, Safflower, Arthraxon hispidus, Styphnolobium japonicum. While synthetic dye causes pollution, natural coloring by plants is as safe and useful as the color itself is lovely. Yet it is tragic to know that this traditional culture of making beautiful natural colors was cut off. There is no way to know today the traditionally correct method to derive colors from the plants. Therefore, it is our aim and challenge to find out the original way to dye and develop it and preserve it as our non-polluted folk art. In regard to natural dyeing, we must say that is very difficult to prepare and preserve natural dyes. In the first place, people had to get the right plants at an appropriate time. Then they could not keep those plants too long. Finally, much depended upon the mordant as well as various conditions and dyeing procedures. All those things influenced greatly the quality of color, some times producing a very pretty color and other times a very dull one. It is very appropriate that the natural dye art should be recognized and appreciated anew by Korea since it provides satisfaction to historical and folk artistic demands as well as to those of fashion conscious modern society for high quality consumption items. We propose two stages of development. The first stage is to explore native dye plants and encourage their cultivation. The second stage is to extract from the plants desirable dye which will enhance national culture.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.454-454
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• 2011

녹색성장은 최근 세계적인 이슈가 되고 있다. 세계물위원회(World Water Council, WWC)의 경우 2012년 마르세유에서 개최되는 제6차 세계물포럼(World Water Forum, WWF)에서 물문제 해결을 위한 신개념 패러다임으로서 '녹색성장(Green Growth)'을 채택하기 위한 협력방안의 필요성을 제안하고 있다. 우리나라에서는 이미 녹색성장을 국가 슬로건으로 선정하고 글로벌 녹색성장연구소(Global Green Growth, GGGI)를 설립하는 등 녹색성장을 선도하고 있다. 이는 물의 중요성에 비추어볼 때 녹색성장을 물 분야에 확산시킬 수 있는 적절한 기회로 보인다. 녹색성장은 물 관련 환경서비스가 환경오염 없는 경제성장을 이룩하는 데 주요한 역할을 수행할 수 있다는 가능성과 당위성에서 파생된 최근에 만들어진 개념으로서, 물 분야의 경우 녹색경제에 있어서 중요한 역할을 수행해왔으며 이후 지속적인 인구증가, 물 소비패턴의 변화, 에너지비용 증가, 기후 변화 등으로 물 분야의 중요성은 더욱 커질 것으로 기대된다. 이처럼 물 관리는 경제발전, 재해로부터 보호, 인간의 건강 및 생태계와 삶의 질을 위하여 필수적이기에 녹색성장에 있어 중요한 역할을 수행하고 있다. 하지만 올바른 물 관리가 녹색성장에 기여할 수 있는 방법에 대해서는 아직 명확화 구체화되지 못하고 있는 실정이다. 이에 따라 녹색성장을 새로운 국가 성장 동력의 패러다임으로 구축하기 위해 수자원분야에서의 녹색성장방법론을 정립하고, 선진국과 개도국 정부들의 균형 있는 참여를 통한 글로벌 파트너십 구축이 요구되고 있으며, 이를 세계물위원회 등 국제기구와 공동으로 연계시킨다면 상당한 시너지 효과가 기대된다. 물관리는 국가의 경제발전, 재해로부터 생명과 재산의 보호, 인간의 건강 및 생태계 다양성 및 건전성 유지와 삶의 질을 향상을 위하여 매우 중요하며, 환경보존과 경제성장을 동시에 추구하는 녹색성장을 실현하는 데 있어서도 가장 핵심적인 사항이라고 할 수 있다. 그러나 올바른 물 관리가 녹색성장에 기여할 수 있는 방법에 대해서는 아직 명확하고 구체화 되지 못하고 있는 실정이다. 따라서 본 연구에서는 '물과 녹색성장'의 이론적 배경, 필요성, 개념정립, 벤치마킹 사례, 국제사회에서의 녹색성장과 관련한 논의 기구 및 흐름 등의 이해를 기초로 녹색성장을 통한 경제성장의 상호작용과 선순환구조를 체계화시키기 위한 균형방안을 제시하고자 한다. 또한 수자원 및 하천관리 분야에서의 WGG구현을 위한 정책제안 및 실행방안이 담긴 중장기 로드맵을 구축하여 물을 통한 성장의 발판을 마련하고자 한다.

• Journal of the Mineralogical Society of Korea
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• v.22 no.2
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• pp.107-114
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• 2009

In present study, an alternative process for manufacturing ultra marine blue by using kaolin, sulfur, sodium carbonate, silica, and rosin was investigated. From the experiments, it was found in the reductive calcination process that the temperature variation with the bed height of input materials is relatively high due to the inadequate thermal conductivity of them. It was also found that the color of the ultramarine blue manufactured is sensitive for the shape of the input materials and the calcinations conditions, and specially the heating rate is very important to form ultramarine. For manufacturing green ultramarine by using sulfur, sodium carbonate, silicon, and pine resin, an optimum condition was investigated to be the heating rate region below $0.6^{\circ}C/min$, the reaction temperature of $850^{\circ}C$ and the reaction time of 4 hr. At the oxidative calcination process to manufacture ultra marine blue from green ultramarine, the optimum flow rate of air is $500{\sim}550\;{\ell}/kg$ (green ultramarine) and the reaction temperature is $500{\sim}550^{\circ}C$.

• Korean Journal of Ecology and Environment
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• v.42 no.3
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• pp.404-406
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• 2009

This study note wished to introduce special-purpose ship for algae removal that is developed by core technology of our country. The ship is consisted of main frame and adjuvant that can attach and detach as cross (+) shape of a character. The characteristics of ship are super light weight and low draft. That is consisted of four devices as suction, collection, filtration and recovering units. Among these, filtration used screen filter (mesh size 30 ${\mu}m$). Also, can separate and remove water and algae by compression air participle notion. Percentage of moisture content of concentrated algal particle was 85%. Water parted with algae finally is exhausted to water area. Removal efficiency that compare by chlorophyll-$\alpha$ concentration was about 57% (inflow: 83.2 ${\mu}g\;L^{-1}$, outflow: 35.8 $[\mu}g\;L^{-1}$) without physical and chemical pretreatment. Forward, need to achieve effect test in various conditions (algal biomass, flow etc.) for efficiency and technological elevation of exclusion device. We wished to contribute in presuppression system construction of massive algal development that manage blue-green algae occurrence area effectively, and prevents spread as lower part of reservoir.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.3
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• pp.183-190
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• 2016

This study carried out an experiment to find out the reaction of hairtail, Trichinus lepturus to the colors of LED light as a basic study on the development of the trolling gear and a method to enable the day-night operation. We used hairtails caught around Seongsan-po, Jeju Island by set nets and hairtail angling. The seven hairtails of the average length 68.9 cm (SD 9.2 cm) and the average weight 135.9 g (SD 47.9 g) were adapted themselves in the experimental water tank, 15 m Self-Governing 1.7 m in height and 1.5 m in depth, and then they were studied. We conducted experiment at the Ocean and Fisheries Research Institute in Jeju Special Self-Governing Province, from November to December 2015, and the sea surface temperature was between 16.5 and $19.5^{\circ}C$. The four colors of LED light, blue, white, green and red, were set up to transmit downward from the marginal area of tank. The 1 meter depth light intensity of LED colors is as follows: $0.09w/m^2/s$ (blue), $0.18w/m^2/s$ (white), $0.04w/m^2/s$ (green) and $0.007w/m^2/s$(red) To know the optimum LED color light, we selected one with better reaction rate after comparison of two colors simultaneously and the selected color was again compared to the other color in a tournament style two times a day (day and night) and ten times totally. The reaction rates were shown as the frequencies of hairtail appearance for 5 minutes in the lighting zone after turning on the LED lights. The reaction rate of the blue was at 97% unlike the red 3% (p < 0.001). The blue was at 75% unlike the green at 25% (p < 0.001). The blue was at 67% unlike the white at 33% (p < 0.001). Therefore, the color of light source showing the highest reaction rate was the blue.

• Journal of fish pathology
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• v.13 no.1
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• pp.37-44
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• 2000

CT(Sodium N-chloro-para toluenesulfonamide, Chloramine-T) known to be a strong oxidative agent was investigated to use as a candidate of disinfectant in the marine aquaculture industry by the analysis of the bactericidal activity against different aquatic microorganisms. One hundred percent mortality appeared at and above 16 ppm CT in sea water in flounder, the predominant species in the marine aquaculture of Korea, when exposed for 48hr. However, bactericidal activity was appeared to be very effective, and all different species of the fish pathogenic bacteria exposed to CT of less than 2 ppm in sea water were dead within 15 min. It allowed us to confirm that CT could be a very effective disinfectant to protect the spread of fish pathogenic bacteria derived from diseased fish or sea water in marine aquaculture. High concentration(10 ppm) with longer exposing time(24 hrs) was required for the algicidal activity of CT, at which concentration might induce the acute toxicity against fish, however, restricted the expanded use of CT for the elimination of zooplanktons at phytoplanktons in marine farms. Moreover the bactericidal activity of CT inhibited almost completely in the present of more than 10 ppm of organic materials pointed out that quality of the culturing sea water should be considered carefully for the application CT to the aquatic farms as a therapeutic agent.

• The Journal of Engineering Geology
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• v.22 no.4
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• pp.439-448
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• 2012

The aim of this study is to develop eco-friendly, fundamental technology for vegetative restoration of barren lands using green rehabilitation material, for the stabilization of abandoned mine debris slopes and depository slopes composed of rock fragments. It is expected that such methods would help to improve the negative view of artificial slopes that remain following mining activity, while also contributing to slope stabilization and prevention of the loss of rock fragments and the dispersion of tailings. We tested the tensile strength and tear strength of various materials, including commonly used natural coir material, natural fibers, and synthetic textile materials with enhanced durability. In conclusion, there is the possibility that natural coir can be used as an eco-friendly material in vegetation restoration, while its durability in natural conditions can be improved by controlling the degree of knot convolution and by antibacterial treatment against biodegradation.