• Title/Summary/Keyword: 1968년도

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한국산 개구리目(Salientia)의 분류 및 분포연구

  • 김헌규
    • The Korean Journal of Zoology
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    • v.14 no.2
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    • pp.118-118
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    • 1971
  • 개구리는 동물학실험, 의학연구, 식료품으로 많이 이용되는 동물이다. 의학연구와 식용으로 가장 적당한 Rana catesbejana Shaw(황소개구리)를 우리나라에 정착시키기에 앞서 우리나라에 서식하는 개구리의 종류 서식환경 및 분포관계를 조사연구하였다. 1913년 이래 우리나라산 개구리를 재료로 구미, 일본, 우리나라학자들이 연구발표한 10편의 논문과 저자가 과거 3년간$(1968 \\sim 1970)$에 채집한 1,883개체 표본을 同定한 결과 旣知種은 모두 10種이었다.

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전력케이블의 열화현상

  • 구자윤
    • 전기의세계
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    • v.37 no.10
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    • pp.54-59
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    • 1988
  • 1968년에 최초로 선진공업국가에서 케이블 열화에 의한 지중 Power Cable의 사고가 발생된 후, utility company는 여러 연구기관과 협력하여 지중배전용 케이블을 수거하여, 케이블의 열화가 계통사고의 원인이 된다는 것을 입증하였다. 또한 고전압 전력계통에 설치된 기존의 OF케이블(oil filled power cable)은 점차로 절연층이 매우 두꺼운 polymer insulated extruded power cable로 대체되어 가는 것이 세계적인 추세이다. 국내에서도 이러한 extruded power cable의 매설이 증가되고 있어, 이에 의한 사고가 발생될 수 있는 potential이 커지고 있기 때문에 우선 전력케이블이 어떠한 이유로 열화되고 어떠한 형태로 나타나는가에 대해 많은 해외연구기관의 연구들을 토대로 간단히 살펴보기로 한다. 열화진단시험방법이나 열화원인분석을 위한 물리화학적 mechanism에 대해서는 다음 기회에 언급하기로 한다.

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한국산 서해낙지(Octopus minor) 정자완성에 관한 미세구조

  • 김상원;장남섭;한종민;황선종
    • Proceedings of the Korean Society of Fisheries Technology Conference
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    • 2001.05a
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    • pp.596-598
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    • 2001
  • 두족강(Cephalopoda)의 정자에 관한 연구는 Chun(1903)의 연구를 필두로 많은 연구가 있었다(Pickford 1940, 1957; Franzen, 1967; Young 1977; Fioroni, 1981; Boss, 1982), 이들 중 Franzen(1967)은 광학 현미경을 통해 Cephalopoda를 대상으로 여러종의 정자 변태 과정을 관찰한 바 있다. 특히 전자현미경을 사용한 연구는 1968년 Galangau와 Tuzet에 의해 시작되었고 정자의 미세구조와 상세한 변태과정이 보고되어져 왔다(Longo & Anderson, 1970; Maxwell, 1974, 1975; Fields & Thompson, 1976; Arnold & Williams-Arnold, 1978; Healy, 1988; Alvarez Perez et al. 1990). (중략)

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Technological Trends in Space Solar Power (우주태양광발전 기술 동향)

  • Yoon, Yong-Sik;Choe, Nam-Mi;Lee, Ho-Hyung;Choi, Jung-Su
    • Current Industrial and Technological Trends in Aerospace
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    • v.7 no.2
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    • pp.33-39
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    • 2009
  • On 1968 Dr. Peter Glaser introduced the concept of a large solar power satellite system in a high geosynchronous orbit for collection and conversion of solar energy into an electromagnetic microwave beam to transmit usable energy to rectennas on earth. With respect to it, U.S.A, Japan, E.U., etc. noted the Space Solar Power(SSP) as a future new energy resource, performed a substantial research and the concept design, and recently announced detailed plans for realizing SSP projects. While the new technology of SSP is developing, U.S.A. and Japan have a plan to provide the electric service by using SSP 2030. This paper presents the technology trend of advanced countries and the domestic strategies on the SSP development as a green energy and a new energy resource.

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The effects of several insecticides on the control of the pear stem sawfly, Janus piri Okamoto et Muramatsu (배나무 줄기벌에 대한 몇 가지 살충제의 방제효과)

  • Yun Ju Kyung
    • Korean journal of applied entomology
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    • v.7
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    • pp.53-55
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    • 1969
  • At Nowan Myun and Bia Myun of Cholla-namdo the pear stem sawflies were found as the most serious pests of the pear trees. The writer attempted to control the pear stem sawfly by spraying certain insecieides in 1968. 1) The significance of each chemical applicated turned out to be as shown in Table 2 and 3. The priority of effectiveness among the chemicals turned out to be as follows: Dimecron>Lebaycid>D. S. >Endrin>Metasystox>DDVP 2) It was also found that the significance vary according to the difference in time of application of the insecticides as shown in Table 2 and 3. Dimecron and Lebaycid were found to be most effective at the hatching day and the 4th day after the hatching.

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CLINICAL STUDY ON TRANSSEPTAL TRANSSPHENOIDAL APPROACH TO PITUITARY GLAND (경비중격 경접형동 뇌하수체 수술에 관한 임상적 고찰 -수술적인 접근 방법에 관하여-)

  • 민양기;정하원;오승하;정종우
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1991.06a
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    • pp.39-39
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    • 1991
  • 뇌하수체 종양에 대한 경비중격 경접형동 수술은 1907년 Schloffer가 비절개수술에 의한 방법을 보고한 이래 1914년 Cushing이 sublabial approach를 정립하였으나, 이후 약 반세기 동안 경비중격 경접형동 수술이 개두술에 비해 종양의 재발율이 높다는 이유로 기피되어왔다. 1968년에 이르러 Cottle의 maxilla-premaxilla approach로 비중격에 대한 수기가 축적되고 수술현미경의 발달로 미세수술이 도입되면서 경비중격 경접형동수술이 다시 각광을 받게 되었다. 이후 sublabial approach, alotomy approach, columellar approach, external rhinoplasty approach 등이 개발되어 보고되었으며 접형동의 함기화가 불완전한conchal 형이나 터어키안 상측부로의 종양의 확장이 심한 예를 제외하고는 모두 이 방법으로 수술을 시행하는 것이 보편화되어 있으며 문헌고찰에 의하면 개두술시의 술후 사망율이 17%인데 비해 경비중격 경접형동술의 경우 1.8%라고 보고되고 있다. 서울대학교병원 이비인후과에서는 sublabial approach로 터어키안까지 종양을 노출시킨 후 신경외과의와 공동으로 뇌하수체 종양을 치료한 예를1977년부터 1988년까지 135례를 보고한 바 있다. 최근에는 sublabial approach의 단점을 보완하면서 외비의 해부학적인 구조에 익숙해질 수 있는external rhinoplasty approach를 이용하여 경비중격 경접형동 수술을 시행하고 있으며 1977년부터의 치험례를 임상분석하여 특히 external rhinoplasty approach의 수술성적을 보고하는 바이다.

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Mineral Nutrition of the Field-Grown Rice Plant -[I] Recovery of Fertilizer Nitrogen, Phosphorus and Potassium in Relation to Nutrient Uptake, Grain and Dry Matter Yield- (포장재배(圃場栽培) 수도(水稻)의 무기영양(無機營養) -[I] 삼요소이용률(三要素利用率)과 양분흡수량(養分吸收量), 수량(收量) 및 건물생산량(乾物生産量)과(乾物生産量)의 관계(關係)-)

  • Park, Hoon
    • Applied Biological Chemistry
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    • v.16 no.2
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    • pp.99-111
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    • 1973
  • Percentage recovery or fertilizer nitrogen, phosphorus and potassium by rice plant(Oriza sativa L.) were investigated at 8, 10, 12, 14 kg/10a of N, 6 kg of $P_2O_5$ and 8 kg of $K_2O$ application level in 1967 (51 places) and 1968 (32 places). Two types of nutrient contribution for the yield, that is, P type in which phosphorus firstly increases silicate uptake and secondly silicate increases nitrogen uptake, and K type in which potassium firstly increases P uptake and secondly P increases nitrogen uptake were postulated according to the following results from the correlation analyses (linear) between percentage recovery of fertilizer nutrient and grain or dry matter yields and nutrient uptake. 1. Percentage frequency of minus or zero recovery occurrence was 4% in nitrogen, 48% in phosphorus and 38% in potassium. The frequency distribution of percentage recovery appeared as a normal distribution curve with maximum at 30 to 40 recovery class in nitrogen, but appeared as a show distribution with maximum at below zero class in phosphorus and potassium. 2. Percentage recovery (including only above zero) was 33 in N (above 10kg/10a), 27 in P, 40 in K in 1967 and 40 in N, 20 in P, 46 in Kin 1968. Mean percentage recovery of two years including zero for zero or below zero was 33 in N, 13 in P and 27 in K. 3. Standard deviation of percentage recovery was greater than percentage recovery in P and K and annual variation of CV (coefficient of variation) was greatest in P. 4. The frequency of significant correlation between percentage recovery and grain or dry matter yield was highest in N and lowest in P. Percentage recovery of nitrogen at 10 kg level has significant correlation only with percentage recovery of P in 1967 and only with that of potassium in 1968. 5. The correlation between percentage recovery and dry matter yield of all treatments showed only significant in P in 1967, and only significant in K in 1968, Negative correlation coefficients between percentage recovery and grain or dry matter yield of no or minus fertilizer plots were shown only in K in 1967 and only in P in 1968 indicating that phosphorus fertilizer gave a distinct positive role in 1967 but somewhat' negative role in 1968 while potassium fertilizer worked positively in 1968 but somewhat negatively in 1967. 6. The correlation between percentage recovery of nutrient and grain yield showed similar tendency as with dry matter yield but lower coefficients. Thus the role of nutrients was more precisely expressed through dry matter yield. 7. Percentage recovery of N very frequently had significant correlation with nitrogen uptake of nitrogen applied plot, and significant negative correlation with nitrogen uptake of minus nitrogen plot, and less frequently had significant correlation with P, K and Si uptake of nitrogen applied plot. 8. Percentage recovery of P had significant correlation with Si uptake of all treatments and with N uptake of all treatments except minus phosphorus plot in 1967 indicating that phosphorus application firstly increases Si uptake and secondly silicate increases nitrogen uptake. Percentage recovery of P also frequently had significant correlation with P or K uptake of nitrogen applied plot. 9. Percentage recovery of K had significant correlation with P uptake of all treatments, N uptake of all treatments except minus phosphorus plot, and significant negative correlation with K uptake of minus K plot and with Si uptake of no fertilizer plot or the highest N applied plot in 1968, and negative correlation coefficient with P uptake of no fertilizer or minus nutrient plot in 1967. Percentage recovery of K had higher correlation coefficients with dry matter yield or grain yield than with K uptake. The above facts suggest that K application firstly increases P uptake and secondly phosphorus increases nitrogen uptake for dry matter yied. 10. Percentage recovery of N had significant higher correlation coefficient with grain yield or dry matter yield of minus K plot than with those of minus phosphorus plot, and had higher with those of fertilizer plot than with those of minus K plot. Similar tendency was observed between N uptake and percentage recovery of N among the above treatments. Percentage recovery of K had negative correlation coefficient with grain or-dry matter yield of no fertilizer plot or minus nutrient plot. These facts reveal that phosphorus increases nitrogen uptake and when phosphorus or nitrogen is insufficient potassium competatively inhibits nitrogen uptake. 11. Percentage recovery of N, Pand K had significant negative correlation with relative dry matter yield of minus phosphorus plot (yield of minus plot x 100/yield of complete plot; in 1967 and with relative grain yield of minus K plot in 1968. These results suggest that phosphorus affects tillering or vegetative phase more while potassium affects grain formation or Reproductive phase more, and that clearly show the annual difference of P and K fertilizer effect according to the weather. 12. The correlation between percentage recovery of fertilizer and the relative yield of minus nutrient plat or that of no fertilizer plot to that of minus nutrient plot indicated that nitrogen is the most effective factor for the production even in the minus P or K plot. 13. From the above facts it could be concluded that about 40 to 50 percen of paddy fields do rot require P or K fertilizer and even in the case of need the application amount should be greatly different according to field and weather of the year, especially in phosphorus.

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A Study on Fluctuations in Biomass of Small Yellow Croaker, Pseudosciaena polyactis, off Korea (한국근해 참조기의 자원량 변동에 관한 연구)

  • ZHANG Chang-Ik;KIM Yong-Mun;YOO Sin-Jae;KIM Chong-Kwan;AHN Soon-Mo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.25 no.1
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    • pp.37-44
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    • 1992
  • Annual biomasses of small yellow croaker, Pseudosciaena polyactis, were estimated by biomass-based cohort analysis (Zhang, 1987) , using data on annual catch in weight at age for 1970-88 in Korean waters. Annual biomass of croaker was highest in 1974 with about 100,000 mt, declining to a level of 20,000-30,000 mt after 1981. Adult biomass also showed a peak in 1974 with about 50,000 mt. Afterwards, however, it continuously dropped. According to the estimates of biomass at age obtained from this analysis, the age composition of small yellow croaker in the 1980's differed greatly from that in the 1970's. The proportions of older croakers (>5 years) were very low in the 1980's and even the biomasses of young croakers (1-4 years) were at a very low level in the 1980's. Year classes of 1968, 1972 and 1978 appeared to be relatively dominant. The mean value of instantaneous fishing mortality (F) in the 1980's was twice that of the 1970's. Recruitment of croaker exhibited an unusally linear relationship with adult stock biomass.

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History of cheese industry in Korea (한국의 치즈산업사)

  • Keum, Jong-Su
    • Food Science and Industry
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    • v.52 no.3
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    • pp.272-286
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    • 2019
  • Cheesemaking is believed to have been first practiced in prehistoric times, about 9,500 years ago, in the area around the Fertile Crescent of Mesopotamia and they left legacy in the name of cheese. Father Chi Chong-Hwan(Didier Serstevens) started for his provost in Imsil Catholic church in 1964. In 1968, cheese was first produced Camembert in Korea by Father Chi Chong-hwan, and then made Mozzarella in 1970, Cheddar in 1972. Father Chi lay the foundation of a cheese industry in Korea. The processed cheese market was highly grown after putting on the market of sliced cheese in the late 1980s, and the various products that complied with wellbeing trends such as organic and high functional cheese produced in the 2000s. The natural cheese opens up a new domestic market after producing Camembert and Brie cheese in the end of 2004. At present, major trends in cheese are authenticity, bold flavor, snack sophistication and tradition. Mozzarella, Parmesan, Cheddar, Provolone, Feta cheese still top in foodservice. In Korea, production of natural cheese is decreasing by the influence of the imported cheese. Production of processed cheese is increasing and total consumption of cheese is also increasing year by year.

Relation between the Heat Budget and the Cold Water in the Yellow Sea in Winter (동계의 열수지 황해냉수와의 관계)

  • Han, Young-Ho
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.14 no.1
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    • pp.1-14
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    • 1978
  • To study the fluctuation of cold water in the East China Sea in summer heat budget of the Yellow Sea in winter was analysed based on the oceanographic and meteorological data compiled from 1951 to 1974. The maintain value of insolation was observed in December($160{\sim}190ly/day$), while the maximum in February ($250{\sim}260ly/day$). The range of the annual variation was found to be less than 50 ly/day. The value of the radiation term ($Q_s-Q_r-Q_h$) was remarkably small (mean 20 ly/day) in winter. It was negative value in December and January, and a positive value in February. The minimum total heat exchange from the sea ($Q_({h+c}$) was found value (471 ly/day) in February 1962, and the maximum (882 ly/day) in January 1963. The annual total heat exchange was minimum (588 ly/day) in 1962, and maximum (716 ly/day) in 1968. If the average deviation of mean water temperature at 50m depth layer were assumed to be the horizontal index ($C_h$) of colder water, $C_h$ is $C_h=\frac{{\Sigma}\limit_i\;A_i\;T_i}{{\Sigma}\limit_i\;A_i}$ where $A_i$ denotes the area of isothermal region and $T_i$ the value of deviation from mean sea water temperature. The vertical index ($C_v$) of cold water can be expressed similarly. Consequently the total index (C) of cold water equals to the sum of the two components, i.e. $C=C_h$$C_v$. Taking the deviation of mean sea surface temperature(T'w) in the third ten-day of Novembers in the Yellow Sea as the value of the initial condition, the following expressions are deduced : $C-T'w=32.06 - 0.049$ $\;Q_T$ $C_h-T'w/2=12.20-0.019\;Q_T$ $C_v-T'w/2=18.07-0.027\;Q_T$ where $Q_T$ denotes the total heat exchange of the sea. The correlation coefficients of these regression equations were found to be greater than 0.9. Heat budget was 588 ly/day in winter, and minimum water temperature of cold water was $18^{\circ}C$ in summer of 1962. The isotherm of $23^{\circ}C$ extended narrowly to southward up to $29^{\circ}N$ in summer. However, heat budget was 716 ly/day, and minimum water temperature of cold water was $12^{\circ}C$ in summer of 1968. The isotherm of $23^{\circ}C$ extended widely to southward up to $28^{\circ}30'N$ in summer. As a result of the present study, it may be concluded that the fluctuation of cold water of the East China Sea in summer can be predicted by the calculation of heat budget of the Yellow Sea in winter.

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