• Korean Journal of Microbiology
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• v.24 no.4
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• pp.341-351
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• 1986

R-plasmid(pSBK203, 2.5Mdal) conferring chloramphenicol resistance was isolated from mutiple antibiotic resistant Staphylococcus aureus D-H-1. Bacillus subtilis BD170 was transformed by this plasmid and restriction enzyme clevage sites of this plasmid were mapped for the cloning of chloramphenicol resistance gene. Taq I partial digested fragment of pSBK203(1.3kb) inserted into Cla I site of pBD9 appears to have both regulatory region for induction and structural gene for chloramphenicol resistance whereas Rsa I fragment (1.3kb, both ends are staggered away 0.1Kb from those of Taq I fragment) inserted into Sca I site of pBR322 showed constitutive expression in E. coli. Hinf I, Taq I, and Bgl II restriction enzyme recognition sites are found in both Rsa I fragment and Taq I fragment. Among these, Bgl II recognition site was associated with chloramphenicol resistance.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.7
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• pp.13-20
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• 2004

In order to set up the design of micro optical bench, optical coupling efficiencies of two sets of test benches are calculated. Simple linear connections of incoming and outgoing optical fibers with and without ball lenses are designed. Positional errors that are possible in actual fabrication processes we considered in the calculations and their tolerances are determined from -3 ㏈ conditions. For a simple fiber-to-fiber connection, the lateral misalignment should be limited to 2.7 um and tilt error 5.8o. In case of the fiber-to-fiber with ball lens, the working distance between fibers can be extended over 60 um. The optical coupling efficiency depends strongly on the positional errors of ball lenses along the optical axis, and it is also found that the lateral and vertical positional errors should be considered simultaneously in order to keep the high coupling efficiency.

• Journal of Life Science
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• v.20 no.10
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• pp.1563-1568
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• 2010

In the course of a research concerning the molecular mechanism of hypocotyl elongation that occurs during soybean seedling growth in darkness, we have generated a number of ESTs from a cDNA library prepared from the hypocotyls of dark-grown soybean seedlings. Comparison of the ESTs assigned a cDNA clone as a putative plastidic ATP-binding-cassette (ABC) protein homologue. The soybean GmNAP1 protein contains an N-terminal transit peptide which targets it into the chloroplast. The transcription level of the GmNAP1 gene was investigated under continuous red light, continuous far-red light, and complete darkness. The main function of this NAP1 protein is the transport of protoporphyrin IX which is the precursor of chlorophyll from the cytoplasm to the chloroplast. The GmNAP1 gene was transferred into the Arabidopsis under the CaMV 35S promoter. The chlorophyll level of this transgenic Arabidopsis plant was much higher than the chlorophyll level of the wild type Arabidopsis plant.

• Korean Journal of Environmental Agriculture
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• v.11 no.3
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• pp.253-260
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• 1992

A photoresponse that results in organisms dispersing from a region of bright light. generally termed photodispersal, is frequently observed in some fishes notably including mud fish (Misgurunus mizolepis G${\"{U}}$NTHER). The primary assumption for this study was that the photodispersion may result from the behavioral strategies of fishes aimed to avoid illumination conditions that could injure the cells in skin tissues via photodynamic sensitization reactions. Here we present some preliminary results that seem to support this assumption : (1) the locomotive action of dark-adapted mud fish was triggered by the onset of illumination with light : (2) blue light (400-500nm) was much more effective in bringing about the locomotive activity than yellow (550-650nm) and red (650-800nm) lights : (3) two blue light absorbing pigments, which photogenerate activated oxygen species, were separated from the skin tissues of mud fish, one of these being identified as riboflavin.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.42 no.2 s.302
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• pp.9-18
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• 2005

Flicker is the 'variation in brightness or he perceived won stimulation by intermittent or temporally non uniform light'. This phenomenon is blown as the cause of eye strain and headaches. Many researchers are dedicated to reducing this phenomenon. The flicker phenomenon also exists in PDP as some other display types, and is a critical problem in 50 Hz PDP. However, it is difficult to define flicker by more than one subjective judgment. So, an objective measurement of flicker is necessary and convenient for research on displays. In this paper, a computational prediction model is proposed which is used to predict luminance flicker (not chromatic flicker) by giving a quantitative output that describes the probability of occurrence of flicker. Through this work, we expected to provide a practical tool for flicker-free design in PDP.

• Journal of Radiation Protection and Research
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• v.36 no.2
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• pp.52-58
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• 2011

OSL dating for three hearths having the sequence of use and discard in No. 29 and 29-1 dwelling sites at Sogol cultural site was carried out. Resulting from the deconvolution of natural CW-OSL decay curve and thermal zeroing test, it was turned out that OSL signal was entirely composed of the heat- and light-sensitive fast component with high photoionization cross-section and all quartz OSL signals were thermally bleached under $300^{\circ}C$ which is the minimum temperature related to heating and cooking in Bronze age. After dose recovery test and plateau test, paleodose of each hearth sample was evaluated by using SAR method, and OSL age was determined from the ratio of paleodose to annual dose rate. For the purpose of the precision improvement of OSL age, Bayesian statistics was applied to each hearth's age and the archaeological sequence information. Finally, it could be concluded to the accurate use period of each hearth from the resultant OSL ages.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.203-203
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• 2011

최근 들어 기후변화에 따른 강우패턴이 바뀌고 각종 하천개발이나 토목공사, 농경지, 경작지 등의 객토 등으로 인해 매년 탁수의 발생이 크게 증가하고 있는 추세이다. 특히 여름철 집중강우의 영향에 따라 상류지역 하천에서 발생하는 부유물질은 호수로 유입되어 장기간 체류하며 심각한 오염원으로서 수중생태계에 치명적인 영향을 주고 있다. 또한 하천과 호수의 상류지역의 농경지나 경작지에서 발생된 부유물질에는 과도한 비료의 사용으로 입자표면에 많은 인을 포함하고 있어 호수 수질악화 및 부영양화의 직접적 요인이 되고 있다. 이에 따라 세계 각국에서는 부유물질은 오염원뿐 아니라 생태계에 영향을 주는 인자로서 엄격히 규제하고 있으며, 특히 농업지역이 많은 하천에 대해서는 유역전체를 대상으로 부유물질에 대한 총량관리를 적용하고 있다. 그러나 우리나라의 경우 하천 수질기준 1급수의 부유물질 농도는 25 mg/l 로서 이는 선진국과 유사한 기준이나 실질적으로 규제가 어려운 실정이다. 수환경에서의 부유물질이란 수체 내 존재하는 유기성, 무기성 물질로써 입자 지름이 2mm 이하의 물에 용해되지 않는 물질을 말하는 것으로, 물의 탁도를 유발시키는 원인이 되며 빛을 차단하여 수생태계에 악영향을 초래한다. 국내 132개 하천을 대상으로 부유물질의 농도와 어류의 종 다양성간 상관성을 조사한 결과, 부유물질의 농도가 15 ~ 20 mg/l 이상에서 종 다양도는 1.0 이하로 급감하는 경향을 보였다(최재석 등, 2004). 한편, 대청호는 1975년부터 1980년에 걸쳐 건립된 저수 면적 $72.8km^2$, 저수량 15억톤의 인공호수로 우리나라 3번째 규모의 인공호수이다. 특히, 대전 및 청주지역의 식수는 물론, 생활용수 및 공업용수를 공급하는 중요한 수자원으로서 부유물질에 대한 모니터링 및 관리가 시급하나 저수 용량이 크고 체류시간이 길어 여름철 부영양화가 매년 반복되고 있다. 따라서 본 연구에서는 부유물질의 농도 변화에 따른 분광반사 특성을 조사하고, 이를 대청호의 Landsat 위성영상에 적용하여 대청호 내 부유물질의 농도변화를 추정하였다. 이와 함께 부유물질 농도 변화에 따른 탁수 환경 모니터링에 원격탐사 기법이 효과적임을 제시하고자 하였다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.9
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• pp.1237-1242
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• 2018

Photodynamic therapy has been suggested as an alternative treatment to current cancer therapy which resulting in a variety of side effects because photodynamic therapy targets specific cancer cells and does not have a significant effect on normal cells. Typically, laser was used as a photodynamic therapy, but this was limited due to high cost and heat reaction. However, compact light emitting diodes that can emit light of various wavelengths have been developed at a low cost, which has a great influence on the low cost development of photodynamic therapy equipment. On the other hand, in the study of photodynamic therapy, the data on the direct effect of visible light are relatively small. Therefore, in this paper, we propose a novel cancer therapeutic module by developing a cancer cell proliferation inhibition module based on an Arduino that is relatively inexpensive, and able to use light of various wavelengths.

• Korean Journal of Food Science and Technology
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• v.21 no.3
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• pp.446-452
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• 1989

The pigment of the Korean cockscomb flower, a betacyanin, was evaluated for its stability in terms of temperature, pH, and its behavior upon exposure to water, light, and air. The pigment was the most stable at pH 4.0, and its activation energy (Ea) for degradation was shown to be 17.55Kcal/mol. In general, sugars protected against color degradation at the concentration of 0.1M. Degradation of this pigment in the presence of food constituents, such as organic acids , metal ions, or antioxidants, at the concentrations normally present in food preparations, can be kept to a minimum by selective adjustment of conditions. This pigment, therefore, has potential value as a food colorant under selected conditions.

• Membrane Journal
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• v.20 no.3
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• pp.235-240
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• 2010

The aim of this paper is to evaluate and compare the performances of forward osmosis (FO) membranes using different materials. The FO membranes were synthesized using interfacial polymerization method on hydrophobic polysulfone (PSf) and relatively hydrophilic polyethersulfone (PES) supports. The FO performance such as flux and back diffusion was measured. The resulting fluxes of PSf and PES FO membranes were $4.3\;L/m^2hr$ and $17.8\;L/m^2hr$, respectively. The flux of the PES FO membrane was higher than that of the PSf FO membrane. The results indicated that hydrophillictity of the support membrane is important for increasing flux in FO process. Moreover, with decreasing the support layer thickness, flux increased considerably.