• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.3
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• pp.215-221
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• 1988

The hop yield prediction model developed based on meteorological elements in Hoeongseong was Y=6,042.846-17.665 $X_1$-0.919 $X_2$-96.538 $X_3$-138.105 $X_4$＋86.910 $X_{5}$ ＋ $X_{6}$ with MS $E_{p}$ of 25.258, $R_{p}$$^{2}$ of 0.9991, R $a_{p}$$^{2}$ of 0.9962 and $C_{p}$ of 7.00. The minimum air temperature at early growing stage ( $X_1$), the total precipitation at cone ripening stage ( $X_2$), the maximum air temperature at flower bud differentiation stage ( $X_3$) and the maximum air temperature at flowering stage ( $X_4$) influenced on hop yield as decrement weather elements. The average air temperature at early growing stage ( $X_{5}$ ) and the total sunshine hours at cone development stage ( $X_{6}$ ) influenced on hop yield as increment weather elements.lements.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.13 no.3
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• pp.103-108
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• 1980

The contents of inorganic conservative constituents in Nagdong River water were determined at Mulgeum where the intake station for Busan city water is located. Samples were taken at intervals of one hour from 7 a.m. to 7 p.m. at spring and neap tides of every month from January 1979 to April 1980. Annual ranges and means of the chemical constituents were as follows: electrical conductivity $99-912\mu\mho/cm,\;200\mu\mho/cm;$ chlorides 6.0-256 ppm, 17.2 ppm; sulfates 4.1-37.9 ppm, 23.5 ppm; calcium 4.2-28 ppm, 13 ppm; magnesium 2.2-23 ppm, 5.6 ppm; sodium 5,0-126 ppm, 14 ppm; and potassium 1.2-10.8 ppm, 2.6 ppm respectively. At several times in this period, the concentrations of chloride ion exceeded 150 ppm that is the criteria for drinking water. The chloride ion concentration was higher at spring tides than that at neap tides and the contents of inorganic conservative constituents were higher in winter than those in summer. The chloride ion concentration showed the highest value at Mulgeum about 4 hors after the high water in Busan harbour.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.2
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• pp.154-159
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• 1991

A field experiment was conducted to know the feasibility of direct-seeded rice. Dry seeds of a Japonica type rice variety, Donghaebyeo, was sown from May 10 to June 20 at the 10-day intervals. The number of days from seeding to emergence decreased as planting date delayed; 13, 12, 10, 9, and 7 days at May 10, May 20. May 30. and June 10 seedings, respectively. The number of maximum tillers per ㎡ was about 700-800 at all the seeding dates and effective tiller ratio ranged 40-45%. The number of days from seeding to heading decreased as seeding date delayed; from 97 days at May 10 planting to 71 days at June 20 planting. The cumulative effective temperature (mean air temperature-15$^{\circ}C$) from seeding to heading was fairly constant having 870$^{\circ}C$ with 2.3% C.V. The number of panicles per unit area at June 10 planting was higher than that of other planting dates. Panicle length and the number of spikelets per panicle tended to decrease as seeding date delayed. The number of spikelets per unit area, 1000-grain weight, and grain yield were similar among the seeding dates except June 20 seeding. At the June 20 seeding the number of spikelets and grain yield were much lower, but 1000-grain weight was higher compared with other seeding dates. Grain fertility and percent ripened grains was similar among all seeding dates.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.5
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• pp.379-387
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• 2012

In order to see the oceanographic conditions, the observations of aquaculture farm of ascidian in Youngdeuk, the east coast of Korea were conducted through 6 times-23 February, 6 April, 8 June, 19 August, 6 October and 20 December-in 2010. Surveys were conducted in 20 stations bimonthly using SBE 19 CTD instrument. The mixed layer depth (MLD) was deep in winter and shallow in summer. The cold water below $5^{\circ}C$ in temperature was occupied below thermocline through all season. The temperature was high in the southeastern area. The salinity was increased from the coast to the open sea. The halocline was distinct at 20 m depth in August and at 40 m depth in October. The lowest value of salinity was appeared at the depth of 10 m in October. In addition the value of precipitation minus evaporation denoted negative in October. These low saline water seemed to inflow to the coast from the open sea. Therefore the low saline water moved to the east coast of Korea. The EKWC may play an important role to convey the low saline water. It may affect the aquaculture farm along the coast as the mass mortality of ascidian. It needs to clarify the role and pathway of EKWC to transfer the low saline water along the east coast of Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.3
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• pp.208-214
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• 2016

This study was conducted to evaluate the effects of different sowing times (May 25, June 10, June 25, July 10, and July 25) on growth and yield of four proso millet (Panicum miliaceum L.) cultivars (Hwanggeumkijang, Manghongchal, Ibaekchal, and Hwangsilchal) at a cultivation area in Iksan, Jeonbuk Province. Heading and ripening times were delayed, with later sowing times in all cultivars, and the periods for heading and ripening were shortened. For sowing from May 25 to July 25, the growth stage was shorter by 40 days in Manghongchal, 38 days in Hwanggeumkijang, 36 days in Hwangsilchal, and 30 days in Ibaekchal. The culm length, ear length, ear width, and culm diameter differed significantly between the cultivars and sowing times. In particular, the culm and ear lengths were considerably reduced when the sowing time was delayed. The grain yield (kg/10a) of Hwanggeumkijang and Ibaekchal was 312 and 359 kg, respectively, for sowing on June 10; and that of Manhongchal and Hwangsilchal was 286 and 404 kg, respectively, for sowing on June 25. Thus, the optimum sowing time was June 25 for Hwanggeumkijang and Ibaekchal, and June 10 for Manhongchal and Hwangsilchal.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1301-1305
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• 2009

본 연구의 목적은 금강권역에 속하는 무주 남대천유역의 유량변화가 유역의 대표어종인 피라미 서식환경에 미치는 영향을 분석하는 것이다. 유량변화를 분석하기 위해 미국의 Nature Conservency에서 개발한 수문변화지표법(Indicators of Hydrologic Alteration)을 사용하여 무주 남대천유역의 1966년${\sim}$2001년의 유량변화를 분석하였다. 유황특성이 바뀌는 1984년을 기준으로 1966년${\sim}$1983년과 1984년${\sim}$2001년의 두 기간으로 나누어 유량변화를 분석한 결과 유량은 증가하는 추세임을 확인할 수 있었다. 따라서 무주 남대천유역의 유량변화가 대표 어종인 피라미의 산란기인 4월${\sim}$5월과 치어기인 6월${\sim}$10월의 하천 서식환경에 큰 영향을 미칠 것으로 판단된다. 본 연구에서 무주 남대천유역의 산란기에 영향을 미치는 4월${\sim}$5월과 치어기에 영향을 미치는 6월${\sim}$10월의 월 평균 유량을 구분하고 수리모형인 HEC-GeoRAS를 이용하여 하도구간의 유속과 수위를 산정함으로써 피라미가 선호하는 생태적 요구조건을 만족하는 서식처 조건의 변화정도를 검토하였다.

• 한국해양학회지
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• v.14 no.1
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• pp.26-31
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• 1979

1976년 7월부터 1978년 5월까지 2년동안 매 기수월에 진해만의 6개 정점에서 식물성플랑크톤군집의 년변화를 조사하였다. 조사기간 중 수온은 2.28$^{\circ}C$~25.48$^{\circ}C$, 염분도는 27.42 ~33.90 , pH는 8.0~8.5, 투명도는 0.5m~0.8m, 용존산소량은 2.23ml/l~12.32ml/l의 분포를 보였다. 식물성플랑크톤의 출현종수는 30속, 79종, 2품종, 3변종으로 나타났다. 이들의 우점종은 Skeletonema costatum, Thalassiosira hyalina, Leptocylindrus danicus, Chaetoceros curvisetus, Chaetoceros costatus, Nitzschia pungens, Nitzschia seriata였으며, Chaetoceros affinis, Chaetoceros curvisetus, Coscinodiscus centralis var. pacifica, Ditylum brightwellii, Navicula distans, Nitzschia pungens, Pleurosigma elongatum, Thalassiorira hyalina, Thalassiothrix frauenfeldii등은 출현빈도에 있어서 이 지역의 대표종이었다. 출현종의 생태적 구분은 연안종이 67.86%로서 내만의 특성을 나타내고 있다. 현존량의 계절적인 변화는 808~12,461,000 cell/l까지 심한 변화폭을 보이고 있으며, 1976년 7월, 11월, 1977년 5월, 9월, 1978년 5월에 $10^{6}$ cells/l대의 대발생이 있었다. 대발생때의 다양성지수는 1976년 7월에 0.5625~1.0345로 낮은 값을 보여 Skeletonema costatum에 의한 대발생이었으며, 11월의 3.0702~4.1019의 높은 값을 보인때는 18~33종의 다양한 출현종에 의한 것이었다.

• The Korean Journal of Malacology
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• v.13 no.1
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• pp.55-64
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• 1997

꼬막, Tegillarca granosa은 우리나라 남해 및 서해안 일대에서 서식하는 중요한 수산자원 중의 하나이지만, 이에 대한 생물학적 기초연구는 거의 없는 실정이다. 따라서 1995년 2월부터 1996년 1월까지 전남 벌교연안에서 채집한 꼬막의 생식소발달, 생식세포형성과정 및 생식주기를 조사하였다. 1. 꼬막은 자웅이체이면서 난생이고, 생식소는 내장낭의 간중장선을 싸고 있는 결합조직으로부터 족부의 근육층까지 분포한다.2. 미분화간층직과 호산성 과립세포들이 초기 활성기의 소낭에 풍부하게 나타나기 시작하여 완숙기에는 거의 없어지는 것으로 보아, 이들은 생식소 및 생식세포형성과 발달에 영향을 공급하는 영향세포로 생각된다.3. 생식소발달, 생식세포형성과정, 조직분화과정 및 세포학적 특성에 따라, 이들의 생식주기를 초기 활성기, 완숙기, 부분 방출기, 방출 및 비활성기 등으로 구분할 수 있다. 4. 방란 및 방정은 수온 2$0^{\circ}C$정도되는 6월하순부터 시작되고, 주산란시기는 수온이 23-24$^{\circ}C$정도 되는 7-8월이며, 완숙란의 크기는 50-60$\mu\textrm{m}$이다.5. 비활성기는 9월에서 이듬해 4월까지 지속되는 비교적 긴 기간이며, 초기 활성기도 비교적 길어 1월에서 5월까지 지속되는 반면, 후기활성, 완숙 및 방출기는 비교적 짧아, 5월에서 8월까지 모두 완료된다.6. 비만도의 월별 변화는 생식소의 발달, 생식주기 및 수온과 밀접한 관계가 있다.7. 사용된 재료 433개체 중 1개체가 자웅동체현상을 나타내었다.

• Korean Journal of Environmental Biology
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• v.24 no.4
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• pp.307-313
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• 2006

Seasonal variation of marine bacterial community was analyzed in the surface sea water collected from one of the stations locating at Tongyeoung coastal area, Korea. The results obtained by the culture method through identification with the VITEK Microbe ID system after pure culture in the selective medium were compared with those obtained by the DGGE based 16S rRNA PCR method. The composition of the marine bacterial community in the sea water samples harvested in September, 2004, November, 2004, January, 2005, May, 2005 and August, 2005 determined by the culture method showed 5, 5, 4, 6, and 10 strains respectively. Pseudomonas fluorescens and Acinetobacter lwoffii were detected in all seasons. The other strains were identified to be Pseudomonas stutzeri, Sphingomonas paucimobilis, Burkholderia mallei and Chryseobacterium indologenes. In contrast, the 16S rRNA PCR-DGGE method detected 10, 11, 6, 9 and 13 populations respectively in the same sea water samples and the strains were identified to be Acinetobacter lwoffii, Burkholderia mallei, Pseudomonas fluoresence, Actinobacillus ureae, Burkholderia sp., Pseudomonas stutzeri, Roseobacter sp., Vibrio parahaemolyticue, Sphingomonas paucimobilis and Rugeria algocolus. This results indicated that the DGGE based 16S rRNA PCR method was more efficient than the culture method for the grasp of the characteristics of the marine bacterial community.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.1
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• pp.43-46
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• 1981

The ratio of the eatable flesh taken from the filefish and its chemical components were investigated from March 1980 to February 1981 and the results are as follows :1. The ratio of the eatable flesh taken from the fish was low during March to June and high during July to December. 2. The moisture content was $81.4-82.0\%$ during March to June, $77.5-80.1\%$ during July to December and $79.4-81.4\%$ during January to February. 3. The protein content was $15.4-15.7\%$ during March to June, $17.0-19.9\%$ during July to December and $16.1-17.0\%$ during January to February. 4. The Lipid content was $0.31-0.41\%$ during March to January, $0.46-0.84\%$ during July to January and $0.43\%$ during February. 5. The carbohydrate content was $0.3-0.4\%$ during March to July, $0.5-0.7\%$ during August to January and $0.3\%$ during February. In conclusion, the ratios of the eatable flesh taken from the filefish and its protein content were highest during July to December in one year.