• Journal of Microbiology and Biotechnology
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• 제21권2호
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• pp.136-146
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• 2011

This study provides first-hand proteomic data on the survival strategy of Anabaena sp. PCC 7120 when subjected to long-term iron-starvation conditions. 2D-gel electrophoresis followed by MALDI-TOF/MS analysis of iron-deficient Anabaena revealed significant and reproducible alterations in ten proteins, of which six are associated with photosynthesis and respiration, three with the antioxidative defense system, and the last, hypothetical protein all1861, conceivably connected with iron homeostasis. Iron-starved Anabaena registered a reduction in growth, photosynthetic pigments, PSI, PSII, whole-chain electron transport, carbon and nitrogen fixation, and ATP and NADPH content. The kinetics of hypothetical protein all1861 expression, with no change in expression until day 3, maximum expression on the $7^{th}$ day, and a decline in expression from the $15^{th}$ day onward, coupled with in silico analysis, suggested its role in iron sequestration and homeostasis. Interestingly, the up-regulated FBP-aldolase, Mn/Fe-SOD, and all1861 all appear to assist the survival of Anabeana subjected to iron-starvation conditions. Furthermore, the $N_2$-fixation capabilities of the iron-starved Anabaena encourage us to recommend its application as a biofertilizer, particularly in iron-limited paddy soils.

• 상하수도학회지
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• 제27권4호
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• pp.457-468
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• 2013

Based on the activated sludge model(ASM), a mathematical model which represents the aerobic sludge digestion by sequencing batch reactor(SBR) combined with ultrasonic treatment was composed and performed in this study. Aerobic digestion using sequencing batch reactor(SBR) equipped with ultrasound treatment was also experimented for the purpose of parameter calibration. Most of the presented kinetic parameters in ASM or ASM2 could be used for the aerobic digestion of sludge but the parameters related in hydrolysis and decay rate needed modification. Hydrolysis rate constant of organic matter in aerobic condition was estimated at $0.3day^{-1}$ and the maximum growth rate for autotrophs in aerobic condition was $0.618day^{-1}$. Solubilization reactions of particulate organics and nitrogen by ultrasonication was added in this kinetic model. The solubilization rate is considered to be proportional to the specific energy which is defined by specific ultrasound power and sonication time. The solubilization rate constant by ultrasonication was estimated at $0.202(W/L)^{-1}day^{-1}$ in this study. Autotrophs as well as heterotrophs also decomposed by ultrasonic treatment and the nitrification reaction was limited by the lack of autotrophs accumulation in the digester.

• 영어어문교육
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• 제18권2호
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• pp.45-66
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• 2012

The purpose of this study was to investigate the impact of two different SNS-based tasks on university students' English writing performance. To address our primary research question, Me2day, microblogging and Social Networking Service, was employed. 43 university students were divided into two experimental groups depending on the task types: a comparison task group and a sharing personal experiences task group. The main findings of the study were as follows: first, two different types of SNS-based tasks, 'spot the differences' and 'writing diaries', had a positive effect on learners' writing performance. The reason for this was that the succinct messages limited to 150 characters made it easier for the students to try writing in English without burden; and they may benefit from their peers by seeing their posts and interacting with each other. Yet there were no significant differences between the two groups when it came to the degree of improvement. Second, two different types of SNS-based tasks differently fostered certain aspects of the writing performance; 'contents knowledge' was supported by the 'writing diaries' task and range was supported by the 'spot the differences' task. Third, learners in the two experimental groups mostly had positive impressions regarding usage of Me2day as a new learning tool.

• Weed & Turfgrass Science
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• 제3권2호
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• pp.130-136
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• 2014

Tall fescue is commonly well-adapted for low maintain area because of its wear resistance, deep root system, and drought tolerances. Deep and infrequent irrigation refers to applying large amounts of irrigation, 1.3 to 2.5 cm or more, in a single irrigation event. Light and frequent irrigation is commonly used with small amounts of water, 0.3 to 0.6 cm, every day or every other day. N use for turfgrass management is often unnoticed for water management. The objective of this field study was to evaluate the effects of irrigation frequency and N rates for tall fescue growth. The three irrigation treatments were no irrigation (precipitation only), 0.5 cm applied every other day, and 1.8 cm applied once a week at one irrigation event. The nitrogen (N) treatments were the low, medium, and high N rate treatments. The low, medium, and high N treatments were applied over 2, 4, and 6 applications, respectively. If high main maintenance of tall fescue is not important and water source is limited, irrigation is not necessary and, the $9.8gNm^{-2}yr^{-1}$ of two applications can be recommended for tall fescue under the weather condition of the study.

• 대한물리치료과학회지
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• 제13권2호
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• pp.17-26
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• 2006

The purpose of this study was to evaluate effect of balance control therapy on low back pain patient's pain and flexibility. The subjects were consisted of 45 patients (15 males, 30 females) who had limited flexion range of motion of full spine with low back pain. All patients were one time treated the balance control therapy. Visual Analogue Scale(VAS) and Finger-to-Floor test(F-T-FT) were measured at pre-treatment, post-treatment and next day. VAS was used to measure subjective pain level. F-T-FT was used to measure forward flexion range of motion of full spine of low back pain patients. The results of this study were summarized as follow: 1. The VAS was significantly reduced between pre-treatment, post-treatment and next day (p<0.001). 2. The F-T-FT was significantly reduced between pre-treatment, post-treatment and next day (p<0.001). 3. The changes of pain decrease were related with pain duration(p<0.05), satisfaction for previous treatment(p<0.001). 4. The changes of flexibility increase were related with satisfaction for previous treatment(p<0.05).

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2000년도 춘계 학술대회 논문집 통권 3호 Proceedings of the 2000 KSRS Spring Meeting
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• pp.49-54
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• 2000

Conventional methods for measuring winds provide wind velocity observations over limited area and time period. The use of satellite imagery for measuring wind velocity overcomes some of these limitations by providing wide area and near condinuous coverage. And its accurate depiction is essential for operational weather forecasting and for initialization of NWP models. GMS-5 provides full disk images at hourly intervals. At four times each day - 0500, 1100, 1700, 2300 hours UTC-a series of three images is received, separated by thirty minutes, centered at the four times. The current wind system generates winds from sets of 3 infrared(IR) images, separated by an hour, four times a day. It also produces visible(VIS) and water vapor(WV) image-based winds from half-hourly imagery four times a day. The derivation of wind from satellite imagery involves the identification of suitable cloud targets. tracking the targets on sequential images, associating a pressure height with the derived wind vector, and quality control. The aim of this research is to incorporate imagery from other available spectral channels and examine the error characteristics of winds derived from these images.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제24권4호
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• pp.227-241
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• 2017

The study investigates the stock market using emotion index calculated from SMD based on investors' emotion. In the VAR anlaysis, we find that the correlation between the KOSPI200 return and emotion score sum is highest in 2- or 3- day lag. This study concludes that explanatory power of the SMD emotion index is limited in explaining the Korean stock market yet.

• 한국국방경영분석학회지
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• 제26권2호
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• pp.90-100
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• 2000

This paper proposes a computer model for airline overbooking. The model is constructed in such as way that users feel easy to find the daily optimal number of additional customers given the reservations already bookded on that day by providing the appropriate cost of denied boarding. In this model, however, the reservations are restricted only up to 40 seats due to the limited P.C. capability. Heuristic approaches may be highly recommended for the larger number of reservations.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2003년도 추계학술대회
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• pp.185-185
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• 2003

In-vitro expanded CNS precursors provide a potentially unlimited source of dopamine (DA) neurons for the experimental treatment in Parkinson's disease. An efficient dopaminergic differentiation from CNS precursors in vitro is limited to mesencephalic precursors isolated from early embryonic ages (embryonic day 11.5 (E11.5)-E12.5).(omitted)

• 한국식품조리과학회지
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• 제22권6호통권96호
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• pp.832-839
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• 2006

Kugija was added to Nabak kimchi to improve the quality and preservation and the optimum addition level was assessed. Kugija extract was prepared by boiling kugija fruits, at different ratios (0, 1, 3, 5, 7%; w/v) in water for 30 minutes. The changes in the physicochemical properties of the Nabak kimchi were measured during storage for 25 days at 10?, and compared to a control (without kugija). The pH was decreased in all treatments. Following the fermentation of Nabak kimchi, the total acidity values were inversely proportional the pH changes according to the nature of mutual dependence. However, in short term, during the initial 7 days of fermentation, the total acidity values decreased with increasing concentrations of kugija extract, whereas the trend was reversed after day 10. Total vitamin C content was directly proportional to the concentration of kugija extract and was decreased with the laps of fermentation. Up to day 25, 7% treatment showed the highest vitamin C content, but at 25 days 1% and 3% treatments ranked the first. The mont of reducing sugar was proportional to the concentration of kugija extract however, the difference of values between all treatments became almost indiscernible after day 25. Turbidity values were generally increased in all samples during fermentation period, although only to a limited extent. The lowest turbidity was shown at 3% treatment up to day 16. Total color difference values were increased up to day 16, but then decreased. The optimum level of kugija extract in Nabak kimchi, as determined through these experiments, was between 1 to 3% per added water content, and was preferably 3% for color and fermentation-retarding effect of the product. Kugija extract could be applied for improving the quality and preservation of traditionally prepared Nabak kimchi.