• Korean Journal of Weed Science
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• v.17 no.1
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• pp.31-43
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• 1997

This study was carried out to investigate classfication of weedy rice (Oryza sativa) based on isozymes esterase and peroxidase, growth and developmental difference of weedy rices and rices grown under dry and water condition, and weedy rice control and tolerant difference of weedy rices in various herbicides using weedy rices collected from thirteen strains of Chonnam, one Chonbuk, two Kyeongki and two rice cultivars. 1. The collected weedy rices were classified into three groups based on isozyme esterase and peroxidase using polyacrylamide gel electrophoresis(PAGE) method. The classified groups were not same each other. 2. Plant height was taller in collected weedy rices than rice cultivars at 18 days after seeding under dry and water conditions, but number of leaves, shoot fresh weight, root fresh weight and root length were not significantly different between collected weedy rices and rice cultivars. In addition, growths of collected weedy rices were greater in dry- than water-condition. 3. After thiobencarb(S-4-chlorobenzyl diethythiocarbamate), molinate(S-ethyl hexahydro-1H-azepine-1-carbothioate) and oxadiazon(5-tert-butyl-3(2,4-dichloro-5-isopropoxyphenyl)-1,3,4-oxadiazol-2-one) were applied at 6 days before seeding, the weedy rices controlled 100% by thiobencarb at 2.1kg ai/ha and 024kg ai/ha oxadiazon treatment but controlled 26% to 67% by molinate at 6.5kg ai/ha. Rice due to the herbicides was injured severely(25% to 100%) in flood condition at time of rice seeding after oxadiazon at 0.48kg ai/ha and 2.1kg ai/ha thiobencarb application, except for molinate which injured rice slightly(4% to 13%) in drain condition. The collected weedy rices to all experimented herbicides showed slight intraspecific variations. The intraspecific variations of weedy rices decreased in the order of thiobencarb>molinate>oxadiazon.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.215-219
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• 2006

Artemisia spp. collections, AC60, AC67, and AC77, that showed the high levels of antioxidant activities and had good growth characters and productivity, were cultivated for mass production. Using selected excellent ones, AC60, AC67, and AC77, after mass production, mugwort teas were made through rubbing and drying processes. Total phenolic compound content, nitrite scavenging ability, and SOD-like activity in mugwort teas and commercial teas were compared. Total phenolic compound content was the highest in AC67 with 109.6 mg/100 ml. Nitrite scavenging ability of AC67 tea was relatively high with 92.5% at pH 1.2 and Jasmine (98.1%), Persimmon Leaf Tea (96.4%), Green tea (98.5%), and Jakseolcha (98.7%) were very high as well. In SOD-like activity, mugwort teas, AC67 (91.7%) and AC77 (93.7%), were high as well as those of Seolrokcha (92.1%) and Rooibos Tea (93.8%). This suggests that AC60, AC67, and AC77 could be used fur making high quality teas as well as Seolrokcha, Jasmine, Green tea, Jakseolcha, Rooibos Tea, Peppermint Herb Tea.

• Journal of fish pathology
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• v.23 no.1
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• pp.1-8
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• 2010

Infectious hematopoietic necrosis virus (IHNV) is the causative agent of IHN, one of the most serious viral diseases of salmonid fish. In this study, glycoprotein (G) gene nucleotide sequence of isolated IHNV RtWanju09 from Jeollabuk-do province was analyzed to evaluate their genetic relatedness to worldwide isolates. As the result, it was revealed that IHNV RtWanju09 isolate belongs to JRt Shizuoka lineage with IHNV RtPy91 and RtJe00. The genetic diversity of G gene between RtWanju09 isolate and RtPy91 isolate from Gangwon-do province was 1.77% and maximum nucleotide diversity among the JRt Shizuoka lineage in Korea was 3.03% during the past 20 years, supporting that the continuous evolution has been occurred among JRt Shizuoka isolates. It was believed that IHNV RtWanju09 isolate has been introduced by the movement of contaminated eggs with IHNV from Gangwon-do to Jeollabuk-do by the reason that the eyed eggs in Jeollabuk-do province used to be obtained from Gangwon-do province. In this study, the domestic transfer of IHNV was firstly investigated by the transfer history of eggs and the phylogenetic analysis using IHNV glycoprotein gene sequence.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.287-287
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• 2009

연료전지는 전기에너지와 열에너지를 동시에 사용 할 수 있기 때문에 에너지 효율이 높고 유해 배기물이 거의 없으므로 친환경적이다. 따라서 환경문제가 대두되고 있는 오늘날, 고효율 친환경의 연료 전지는 차세대 에너지원으로 각광받고 있다. 보일러와 계통선에서 열과 전기를 공급받는 기존방식에 비해 연료전지 코제너레이션 시스템의 경우 20%이상 에너지 절감율을 향상시킬 수 있다. 기존 10kW이하의 소용량 발전설비의 경우 대형 발전소와 같은 수준인 30%이상의 전기 효율을 기대할 수 없으나 고분자 전해질 연료전지를 적용할 경우 1kW급에서도 35%의 전기 효율을 기대할 수 있으며 열회수까지 고려할 경우 80%에 가까운 열효율을 달성할 수 있다.(4)연료전지 시스템은 연료전지 스택 이외에, 연료변환장치, 급기설비, 열 및 물관리 설비, 전력변환장치 그리고 제어 장치 등으로 구성된다. 연료전지 시스템 성능은 연료전지 스택의 성능에 가장 의존적인데 연료전지 스택의 성능은 같은 스택이라도 운전 및 제어 방법에 따라서 다양하게 변할 수 있다. 실제로 연료전지 스택 자체의 전기 변환 효율은 최대 40% 까지로 매우 높으나, 다양한 운전 조건에 따라 효율이 30~40% 수준에서 변화는 것이 현실이다. 때문에 시스템을 설계할 때에는 종합화된 시스템 측면에서의 운전까지 고려한 설계와 성능 해석이 필요하다. 그간 연료전지를 활용한 가정용 열병합 발전분야에서는 시스템 설계를 위한 시뮬레이션 기반 성능 해석에 관한 연구가 활발히 진행되어왔다. 하지만 연료전지 스택의 경우 간이화된 성능 모델식을 사용하여 이로 인한 성능 예측모델의 오차가 크게 발생하여 전체 시스템 최적화의 저해요인으로 작용하여왔다. 따라서 본 연구에서는 가정용 연료전지 열병합 발전 시스템을 자체적으로 설계 개발하였으며 이 중 연료전지 스택의 성능모델을 실험기반으로 구축하였다. 먼저 가정용 연료전지 열병합 발전 시스템의 설계는 크게 네 단계로 구분되며 이는 1) 시스템 개념 설계, 2) 연료전지 스택 설계, 3) 주변장치 설계, 4) 제어시스템 설계로 이뤄진다. 연료전지 스택의 성능 모델은 고분자연료전지의 성능에 가장 민감하게 영향을 미치는 온도 및 습도의 변화에 따른 다양한 스택 성능을 예측 가능하도록 개발하였으며 이는 간단한 이론 모델의 구조에 실험 데이터를 기반으로 모델 파라미터를 도출하는 기법으로 이뤄졌다.

• Applied Biological Chemistry
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• v.48 no.1
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• pp.16-22
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• 2005

Many chitosanases, glycosyl hydrolases that catalyze the degradation of chitosan, have been found in microorganism. In this paper, classification of the enzyme has been described, which is based on the amino acid sequence (families) and splitting patterns (subclasses). Glycohydrolytic mechanisms such as inversion and retention of the substrate anomer are also discussed in context of the families. Interrelationship among the primary structure, clan, anomeric conversion and the splitting patterns has been suggested. In addition, advanced definition of chitosanase was introduced through the investigation of enzymatic products from partially N-acetylated chitosan as a substrate.

• Journal of Korean Society of Forest Science
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• v.30 no.1
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• pp.1-7
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• 1976

This study was performed in Bo-Eun Gun, Chung-Cheong Buk Do. The forest types having been classified, the each area was measured by dot-grid method. The 820 sample points having been obtained by systematic sampling method, the tree heights, crown densities, crown diameters in the points were measured on the aerial photography, and the volumes per hectare were estimated by the comparison with stereogram. Thirty eight plots, which amounted to about 4.5% of all the sample points, were sampled with double sampling method and volume were measured by the ground survey method. the results were summarized as follows; 1. There is no significant differentia between the values measure by dot-grid method and the statistical values obtained by the authority for the area. 2. There is no significant differentia between the estimated values and the measured values for the volume. And the coefficient (b) was 1.18. 3. The heights of conifer trees were easily measured more or less, but it was some difficult for the deciduous trees, because the tops of trees were not observed easily. 4. All the values had a tendencies to be overestimated in the low stocked stand and to be underestimated in the high stocked stand. 5. When the aerial volume table method by ground checking needs to be used together, the work should be performed by the experienced technician and the photgraphic volume table should be made in advanced of the work.

• Korean Journal of Plant Taxonomy
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• v.43 no.1
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• pp.34-45
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• 2013

The Polygonum amphibium complex (Poygonaceae) is a highly polymorphic taxon that can grow in aquatic environments as well as in moist terrestrial habitats. Aquatic and terrestrial plants of the P. amphibium complex vary significantly in morphology and exhibit very complicated patterns of morphological variation, resulting in the description of numerous infra-specific taxa. Principal components analysis of 107 individuals of the P. amphibium complex from Asia and North America using 11 morphological characters showed that the aquatic plants can be discerned from the terrestrial plants by leaf size, shape, and petiole length. In contrast, both aquatic and terrestrial plants collected from the same population or locality shared identical sequences in the matK, psbA-trnH IGS, rbcL-accD IGS and trnL-trnF regions of the chloroplast DNA (cpDNA), suggesting that aquatic and terrestrial forms of the P. amphibium complex are not genetically diverged; morphological differences between the two forms are probably due to the differences in environmental conditions of the habitats. In addition, results from the morphological analysis and the maximum parsimony analysis of the cpDNA data set revealed that the plants from Asia including Korea, Japan, China, Mongolia and Russia Far East are diverged from those in North America and Europe, suggesting that the Asian populations should be recognized as a distinct variety, P. amphibium var. amurense Korsh.

• Korean Journal Plant Pathology
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• v.1 no.1
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• pp.3-11
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• 1985

Three mild mutant strains of tobacco mosaic virus (TMV) were isolated from Nicotiana tabacum var. Samsun incubated at $38^{\circ}C$ for 10 days after inoculation with a wild type of TMV-OM strain. They were designated into Tg 5272, Tw 227 and Tw 333. All mild strains could be distinguished from TMV-OM by their reactions on different indicator plants. The mild strains induced the mild mottling without distinct symptoms, whereas the wild strain produced severe mosaic, rugose and stunting on tobacco and red pepper plants. Tw 227 and Tw 333 produced smaller necrotic spots than those of Tg 5272 and TMV-OM on N. glutinosa and Datura stramonium. The former two strains also produced ring spots and mosaic on Gomphrena globosa compared with necrotic spots by the latter strains. Three mild strains were serologically identical to TMV-OM. Their physical properties were thermal inactivation point $80-85^{\circ}C$, dilution end point between $10^{-4}\;and\;10^{-6}$, and longevity in vitro 7days or longer. Ultraviolet absorption spectra of purified preparations of the mild strains and TMV-OM were identical, with a minimum at 247nm, a maximum at 260nm, and a slight shoulder at 290nm. Electrophoresis of the strains in polyacrylamide-agarose gel showed that all the strains formed one major band and two minor bands, except for one minor band of Tw 333. However, when sodium dodecyl sulfate was added to the purified viruses before electrophoresis, each strain formed only one major band.

• Korean Journal of Poultry Science
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• v.41 no.1
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• pp.39-44
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• 2014

The goal of this study was to evaluate the growth performance of crossbred strains using Korean native chicken (KNC). The data were collected from 2012 through 2013 at Poultry Science Division, National Institute of Animal Science, Korea. The number of chicks analyzed in this study was 375. Crossbred were (A) $R{\times}S$, (B) $D{\times}H$, (C) $D{\times}S$, (D) $C{\times}Y$ and (E) $Y{\times}H$. The fertility rates of strains were 94.9% in crossbred A, 91.9% in crossbred B, 91.8% in crossbred C, 89.7% in crossbred D and 93.8% in crossbred E, respectively. The fertility was highest in crossbred A, but crossbred C showed the lowest (p<0.05) based on the hatchability. The crossbreds B and C exhibited a superior performance on body weight gains during growing stages but crossbred D showed the lowest (p<0.05). The feed intake was to the pattern of body weight. The feed intake of crossbred D was significantly lower than other crossbreds. Also, feed conversion ratio of crossbred D showed the lowest (p<0.05). Egg production ratio of crossbred D was significantly higher compared to the other crossbreds. These results suggest that the development of new crossbreds of commercial Korean Native Chickens should be required for better performance.

• Research in Plant Disease
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• v.7 no.1
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• pp.1-7
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• 2001

An isolate of Cucumber mosaic cucumovirus(CMV) was isolated from Hydrangea macrophylla for. otaksa(Sieb. et Zucc. ) Wils. showing mosaic symptoms, and designated as Hm-CMV. Hm-CMV was characterized by the tests of host range, physical properties, serological properties, RNA and coat protein compositions, and reverse transcription and polymerase chain reaction (RT-PCR) analysis. Twelve species in 4 families were used in the host range test of Hm-CMV and could be differentiated from Y-CMV used as a control CMV by the ringspot and line pattern on inoculated leaves of several tobacco plants. Thevirus produced local lesions on inoculated leaves of Chenopodium amarticolor, C. quinoa and Vigna unguiculata. The physical properties of the virus were as follows; thermal inactivation point(TIP) was 60$\^{C}$, dilution end point (DEP) was 10$\^$-3/, and longevity in vitro (LIP) was 3∼4 days. Hm-CMV was serologically identical to Y-CMV. SDS-polyaciylamide gel electrophoresis(SDS-PAGE) showed one major protein band of about 28 kDa. In RNA or dsRNA analysis, Hm-CMV consisted of four RNA or dsRNA species, but satellite RNA was not detected. In RT-PCR using CMV-common primer and CMV subgroup I-specific primer, bothe amplified expected size of about 490 bp and 200 bp DNA fragments from Hm-CMV, respectively. Restriction enzyme analysis of the 490 bp RT-PCR products using EcoR I and Msp I showed that Hm-CMV belonged to CMV subgroup I. However, Hm-CMV could be differentiated from other CMV subgroup I isolates by RNA fingerprinting by arbitrarily primed polymerase chain reaction (RAP-PCR).