• Title/Summary/Keyword: 단기시험

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Screening for Antioxidative Activity of Crude Drugs (항산화성(抗酸化性) 생약(生藥)의 선발(選拔))

  • Kim, Seung Yeol;Kim, Jin Hwan;Kim, Seung Kyeom
    • Korean Journal of Agricultural Science
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    • v.19 no.1
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    • pp.103-114
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    • 1992
  • Screening for antioxidative activities of 180 species of crude drugs were performed on their methanol extracts. More than 45% of those showed some effect on oxidative stability of linoleic acid, and 44 species seemed to have rather strong antioxidative activity. Selected these samples of the active crude drugs were further examined in their methanol extracts with methyl linoleate emulsion system. especially 11 species revealed strong antioxidative activity. These 11 species were then successively extracted with ethyl acetate and petroleum ether, and their antioxidative activity was determined. The ethyl acetate and petroleum ether extracts of Epimedium Koreanum NAKAI, Psoralea Corylifolia L., Syringa Dilata NAKAI and Prunus mume Sieb, et Zucc. showed much more effective than the others in stabilizing methyl linoleate. Scutellaria baicalensis George. Glycyrrhiza glabra L. were only effective in the methanol extract.

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Effect of Seed Condition, Grain Filling Period and Cold Stratification Treatment on Germination of Bupleurum falcatum L. (자호(紫胡)의 종자조건(種子條件), 등숙기문(登熟期問) 및 저온층적처리(低溫層積處理)가 발아(發芽)에 미치는 영향(影響))

  • Chung, Hae-Gon;Seong, Nak-Sul;Chae, Jae-Cheon
    • Korean Journal of Medicinal Crop Science
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    • v.2 no.1
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    • pp.32-37
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    • 1994
  • This experiment was conducted to obtain the basic information for the increase ofgermination percent by the seed diameter, specific gravity, different grain filling period and stratification in Bupleurum falcatum seeds. The seed size of B.falcatum ranged from 2.0 to 3.9mm in diameter, The large seed showed the higher germinability, The optimum specific gravity of salt selection for seed screening was 1.05 resulting in screening out seeds with high germinability over 70%.The seeds needed grain filling period for 60 days or longer after flowering to keep high germinability The optimum period of stratification treatment to promote seed germination was about 80 days.

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Effect of Joint Spacing on Early-Age Behavior of jointed Concrete Pavement (줄눈콘크리트 포장의 줄눈간격에 따른 초기거동 연구)

  • Yoon, Chang-Ho;Lee, Jae-Hoon;Kim, Hyung-Bae;Lee, Seung-Woo
    • International Journal of Highway Engineering
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    • v.9 no.3
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    • pp.101-110
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    • 2007
  • Joint Spacing of Jointed Concrete Pavement has been uniformly designed and constructed as six-meter in Korea. However, engineering backgrounds to show the appropriateness of six-meter Joint Spacing has not been provided. In the on-going reseach of the development of Korea Pavement Reseach Program(KPRP), the optimum Joint Spacing is suggested as 6 to 8 meters according to the regional climatic conditions based on the mechanical-empirical analysis of short-term and long-term pavement distress. This study is a part of the investigation on the adequateness of Joint Spacing design specification suggested in KPRP. Joint Spacing was design and constructed as seven-meter Joint Spacing suggested as design specification in Korea Reseach Program(KPRP) and monitored the Load Transfer Efficiency(LTE), Random crack and compared with those of adjacent $6{\sim}7$ meter Joint Spacing concrete section.

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A Study on Rheological Behavior of Korean Straight Asphalts (국내 스트레이트 아스팔트의 거동 특성 연구)

  • Kim, Nam-Ho;Hwang, Sung-Do;Park, Young-Cheol
    • International Journal of Highway Engineering
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    • v.1 no.2
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    • pp.121-133
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    • 1999
  • This study was based on the evaluation of 9 asphalts that were produced in five major Korean refineries. The study was concentrated to identify the problems of the current asphalt specification (KS M 2201) and to determine the ranges of visco-elastic asphalt behavior. As a conventional asphalt property. asphalt penetration, ring and ball(R&B) softening point, asphalt viscosity, and flash point of asphalt were measured. Also Dynamic Shear Rheometer (DSR) were used to evaluate visco-elastic properties of asphalts in the $-20^{\circ}C$ through $30^{\circ}C$ temperature range. These properties before and after the short-term (RTFO) and long-term (PAV) aging were compared and analyzed to achieve the research objectives. The conclusion from this study can be summarized by the followings. The low temperature rheological behavior of all the straight asphalt from five major Korean refineries is similar regardless of asphalt grade. In the mean while, the rheological behavior at high and intermediate temperature of Korean straight asphalt varies depending on asphalt grade.

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A Study on the Effects of the System Marginal Price Setting Mechanism of the Cost Function in Operating Modes of the Combined Cycle Power Plants in Korea Electricity Market (한국전력시장에서 복합발전기의 운전조합별 비용함수의 계통한계가격(SMP) 결정메커니즘 영향에 관한 연구)

  • Yoon, Hyeok Jun
    • Environmental and Resource Economics Review
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    • v.30 no.1
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    • pp.107-128
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    • 2021
  • It has been recognized that implementing the marginal price mechanism to CBP is not acceptable due to the lack of revenue of the marginal generators. This study shows that it is not the problem of marginal price mechanism but the structural problems originated by the suspension of restructuring, the technical limits of RSC program and inaccuracy of the generation cost estimation method. This study explains the method to calculate the cost function in operating modes of the CC generators and proposes the modeling for the CC generators in RSC program. To implementing the cost function in operating modes could give an opportunity to change the price setting mechanism from average to marginal cost. The price setting mechanism based on the marginal cost will be one of the main points to provide the right price signals and to introduce a real-time and A/S markets to prepare the energy transition era.

Development of drought frequency analysis program (가뭄빈도해석 프로그램 개발)

  • Lee, Jeong Ju;Kang, Shin Uk;Chun, Gun Il;Kim, Hyeon Sik
    • Proceedings of the Korea Water Resources Association Conference
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    • 2020.06a
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    • pp.14-14
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    • 2020
  • 일반적으로 수문빈도해석은 치수계획 수립에 이용되는 설계강수량, 계획홍수량 등을 산정하기 위해 연최대치계열 또는 연초과치계열 자료를 이용한 극치빈도해석을 수행하고, 확률분포의 우측꼬리(right tail) 부분을 이용하여 확장된 재현기간에 해당하는 확률수문량을 추정한다. 하지만 가뭄 관련 분석에서는 확률분포의 좌측꼬리(left tail) 부분은 이용해 확장된 재현기간별 확률수문량을 추정해야할 경우가 발생한다. 또한 물관리 실무에서 장 단기 운영계획 수립을 위해 이용하는 갈수빈도 유입량 산정 등에서도 평년보다 작은 수문량에 대한 빈도해석이 필요한 경우가 있다. 국가 가뭄정보분석센터에서는 기존에 K-water연구원에서 개발한 빈도해석 프로그램인 K-FAT의 분석모듈을 이용해 극소치계열 또는 갈수빈도 유입량 분석에 특화된 가뭄빈도해석 프로그램을 개발하였다. 본 프로그램은 GEV, Gumbel, Weibull 등 14개의 확률분포형을 포함하며, 모멘트법, 최우도법 및 L-모멘트법을 사용하여 매개변수를 추정한다. 적합도 검정의 경우 χ2, K-S, CVM, PPCC 및 수정 Anderson-Darling test를 이용하여 다각적인 검정을 할 수 있도록 하였다. 분석을 위한 입력 자료의 경우 사용자가 전처리를 통해 준비한 연최소치계열 등 연도별 시계열자료를 이용할 수 있으며, 일단위 및 월단위의 강수량 또는 댐 유입량 자료를 이용해 사용자가 원하는 기간의 누적강수량, 평균 유입량으로 변환할 수 있는 자료변환 기능을 추가하여 실무 활용성을 높였다. 또한 최적 확률분포 선정을 위해 참고할 수 있도록 AIC(Akaike information criteria)와 BIC(Bayesian information criteria) 분석이 포함되어 있으며, Bootstrap 기법 등을 이용한 불확실성 산정을 통해 추정 값의 신뢰구간을 표시하도록 하였다. 개발된 프로그램은 베타버전 시험배포를 거쳐 가뭄정보포털을 통해 배포할 예정이다.

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Recent Advances in the Prevention of RSV in Neonates and Young Infants

  • Ki Wook Yun
    • Pediatric Infection and Vaccine
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    • v.30 no.1
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    • pp.1-11
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    • 2023
  • Respiratory syncytial virus (RSV) is a pathogen with a high burden of disease and social cost among infants worldwide, but the development of a vaccine has been delayed. The recent understanding of the pathogenesis of RSV, progress in reverse genetics, and successful implementation of other maternal immunizations have prompted the recent rapid development of monoclonal antibodies (mAbs) and vaccines for RSV prevention. Phase 3 clinical trials for two next-generation mAbs (nirsevimab and clesrovimab) and two maternal RSV pre-F vaccines are currently underway or have been recently completed. Soon, we might be able to protect young infants through long-acting mAbs and/or maternal immunization. Additionally, the development of live-attenuated vaccine candidates that are capable of avoiding enhanced RSV disease is ongoing. We need to gain familiarity with these newly developed strategies and collect epidemiological data on domestic RSV to adequately prepare for a new era of RSV prevention.

The Influence of Traffic Time and Fertilizer Type on the Quality of Golf Course Putting Greens (답압시간과 비료종류가 골프코스 그린 잔디의 품질에 미치는 영향)

  • Lee, Sung-Woo;Lee, Jae-Pil;Kim, Doo-Hwan
    • Asian Journal of Turfgrass Science
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    • v.22 no.1
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    • pp.65-74
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    • 2008
  • Traffic management is becoming an important issue in turfgrass practise on golf course. The objective of this study was to investigate the combined impact of different traffic times and types of fertilization. Traffic treatment was applied in morning (AM), noon, and afternoon (PM). Fertilizers used include faster-release fertilizer (21-17-17) and slow-release fertilizers (12-6-18, 11-3-22, 20-3-20, 10-3-10). Experiment was conducted from Oct. 1 to Nov. 30, 2005 on a nursery putting green of Incheon Grand Golf Club. The growth and quality of creeping bentgrass (Agrostis polustris cv. 'Seaside II') were evaluated on visual leaf color, leaf texture, shoot density, and root length. The measurement at 20 days after treatment, turfgrass color and leaf texture showed the best result on 10-15-10 + Noon-traffic plot. Turf quality and traffic tolerance were not different at Am and Pm traffic treatment. However, traffic stress in early morning and late evening caused the most severe damage to the turfgrass. Shoot density was the highest in 10-15-10 + Noon-traffic treatment but root length was not different among treatments after 30 day measurement. Among the fertilizers, slow release fertilizer resulted in higher turf quality and traffic tolerance than fast release fertilizer, however, shoot density did not showed a significantly different. For the fast recuperation of turfgrass from traffic injury in the early winter, it is recommended to avoid early morning and late evening traffic such as cup replacement and other maintenance practise. It is also recommended to delay the first tee-up time and ending early for last tee time during cold weather season.

Effect of Medicinal Herb Composites on Antioxidative and Cognition-Enhancing Activities in Rats (생약복합물이 흰쥐의 체내에서 항산화 및 인지개선활성에 미치는 영향)

  • Kang, Jin-Soon
    • The Korean Journal of Food And Nutrition
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    • v.29 no.3
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    • pp.382-391
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    • 2016
  • The purpose of this experiment was designed to investigate the effects of medicinal herbs (MH) extracts on dementia induced by trimethyltin chloride (TMT) in rats. Six-week-old male Sprague-Dawley rats were randomly divided into five groups; normal group (group 1), control group (group 2), MH extracts group (250, 500 mg/kg) (group 3, group 4) and positive control group (tacrine group, group 5). In the control group to induce dementia, a 2.5 mg/kg of TMT intraperitoneal injection was used for 14 days (1 per day) in the rats. In the MH extracts group 250 mg/kg and 500 mg/kg of MH extracts were medicated in an oral inoculation for 20 days (1 per day). After 30 minutes, a 2.5 mg/kg of TMT intraperitoneal injection, which causes dementia, was used for 14 days (1 per day). In the positive control group (Tacrine group) 10 mg/kg of Tacrine, the dementia treatment, was medicated in an oral inoculation. After 30 mintues, 1 mg/kg of TMT intraperitoneal injection, which causes dementia, was used for 14 days (1 per day). The present author observed the passive avoidance performance test, and memory ability test (Y maze test), the values of MDA, acetlycholinesterase (AchE) activity in the brain and antioxidant enzyme in serum. MH extracts significantly improved memory of AD model rats in the Y-maze test, and also significantly improved memory of AD model rats in the passive avoidance test. MH extracts significantly reduced AChE activity, and significantly increased the SOD level, but not catalase and MDA. From the results above, MH extracts is thought to be effective in the improvement of antioxidant enzymes and memory ability.

A New Short Growth-Duration Rice Cultivar, "Keumo 3" (소득작물 전후작용 단기성 벼 품종 "금오3호")

  • Kang, Jong-Rae;Lee, Jong-Hee;Kwack, Do-Yeon;Lee, Jeom-Sik;Park, No-Bong;Ha, Woon-Gu;Park, Dong-Soo;Yeo, Un-Sang;Lim, Sang-Jong;Oh, Byeong-Geun
    • Korean Journal of Breeding Science
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    • v.41 no.3
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    • pp.292-298
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    • 2009
  • A new rice cultivar "Keumo 3" was developed for adopting under double cropping system with after or before cash crop cultivation. It was selected from the cross-combination between YR17202 $F_2$/Shinkeumobyeo//YR15727-B-B-B-102. The parent, YR17202 $F_2$ individual plant, was used for tolerance to lodging, it derived from a cross between Nonganbyeo/Shinkeumobyeo. Nonganbyeo is well known to lodging tolerance cultivar, as well as biotic stress, because it was developed by crossing with Tongil type. And the YR15727-B-B-B-102 line used as another parent with short growth duration, likewise highly resistance to rice blast disease. The pedigree derived from the cross-combination YR17202 $F_2$/Shinkeumobyeo//YR15727-B-B-B-102 were generated to $F_7$, and a best line among them named as Milyang 201. After a series of yield trials, including local adaptability test conducted throughout the peninsular of Korea, Milyang 201 was registered with the name of "Keumo 3" in 2005. The cultivar belongs to a early maturing group and heads 4 days earlier than Keumobyeo, a standard cultivar. It has short culm, and less spikelet number per panicle than Keumobyeo. However, its milled rice yield grown under extremely late transplanting time, 10. July, over the 3 local sites for 2003-2005 years, averaged 4,48 MT/ha, which is 6% higher than the standard, Keumobyeo. "Keumo 3" has showed a durable resistance to leaf blast disease during fourteen blast nurseries screening covered from south to north in Korea for 2003-2007 years. And it was confirmed harbours pi-zt, a durable blast resistance gene. Moreover it was incompatible with 19 blast isolates under artificial inoculation, except one isolate, K1101. Additionally, "Keumo 3" exhibits resistance to $K_1$, $K_2$ and $K_3$ of bacterial blight pathogen, as well as strip virus disease resistance, and moderate resistance to dwarf virus disease. Consequently, the new rice cultivar "Keumo 3" would be well adopted where a bio stress makes a big problem annually.