• Title/Summary/Keyword: the 1970s

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A Study on the Stock Assessment and Management Implications of the Hairtail, Trichiurus lepturus Linne in Korean Waters 2. Variations in Population Biomass of the Hairtail, Trichiurus lepturus Linne in Korean Waters (한국 연근해 갈치의 자원평가 및 관리방안 연구 2. 한국 연근해 갈치의 자원량 변동)

  • ZHANG Chang Ik;SOHN Myoung Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.4
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    • pp.620-626
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    • 1997
  • Annual biomasses of the hairtail, Trichiurus lepturus, were estimated from the biomass-based cohort analysis (Zhang, 1987), using data of annual catch in weight at age during $1970\~1988$ in Korean waters. Annual biomass of the hairtail was peaked at about 240,000 mt in 1975, and thereafter declined with a slight fluctuation. Adult biomass showed a peak in 1978 with about 55,000 mt. However, it has continuously decreased untill 1980 to the level of 9,000 mt and remained at this level till 1988. Age compositions of the hairtail in the 1980s differed greatly from those in the 1970s. The proportions of older hairtail (>4 years) were very low in the 1980s and even the biomasses of young hairtail $(1\~3\;years)$ were at a low evel in the 1980s compared with the level in 1970s. The 1973 and 1974 year classes appeared to be relatively dominant. The mean value of instantaneous rate of fishing mortality (F) in the 1980s was significantly different from that of the 1910s (P<0.05). Recruitment of the hairtail exhibited a similar trend with stock biomass until 1974, indicating the density-dependent Ricker curve.

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Unmanned Lunar Exploration Failure Case Analysis (해외 무인 달 탐사 실패 사례 분석)

  • Yang, Jeong-Hwan
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.48 no.3
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    • pp.233-242
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    • 2020
  • The history of mankind's lunar exploration began in 1958 with the United States of America "Pioneer 0" mission. In 1950s~1970s, the United States of America and Union of Soviet Socialist Republics carried out missions and experienced numerous failures to explore the moon. Since the 1990s, Japan, Europe, China and other Advanced country in Space technology have started to explore the moon and in 2016, Korea began to develop the lunar orbiter for lunar exploration. This paper analyzed the failure cases and causes of the lunar exploration in the USA and the USSR in the 1950s~1970s according to the mission purpose. Examples of mission delays, cancel, and failures that occurred during lunar exploration in post-1990s were presented. Through the investigation and analysis, this paper is intended to serve as a reference of the lunar exploration mission that Korea is working on or will be performing in the future.

Changing Trends of Climatic Variables of Agro-Climatic Zones of Rice in South Korea (벼 작물 농업기후지대의 연대별 기후요소 변화 특성)

  • Jung, Myung-Pyo;Shim, Kyo-Moon;Kim, Yongseok;Kim, Seok-Cheol;So, Kyu-Ho
    • Journal of Climate Change Research
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    • v.5 no.1
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    • pp.13-19
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    • 2014
  • In the past, Korea agro-climatic zone except Jeju-do was classified into nineteen based on rice culture by using air temperature, precipitation, and sunshine duration etc. during rice growing periods. It has been used for selecting safety zone of rice cultivation and countermeasures to meteorological disasters. In this study, the climatic variables such as air temperature, precipitation, and sunshine duration of twenty agro-climatic zones including Jeju-do were compared decennially (1970's, 1980's, 1990's, and 2000's). The meteorological data were obtained in Meteorological Information Portal Service System-Disaster Prevention, Korea Meteorological Administration. The temperature of 1970s, 1980s, 1990s, and 2000s were $12.0{\pm}0.14^{\circ}C$, $11.9{\pm}0.13^{\circ}C$, $12.2{\pm}0.14^{\circ}C$, and $12.6{\pm}0.13^{\circ}C$, respectively. The precipitation of 1970s, 1980s, 1990s, and 2000s were $1,270.3{\pm}20.05mm$, $1,343.0{\pm}26.01mm$, $1,350.6{\pm}27.13mm$, and $1,416.8{\pm}24.87mm$, respectively. And the sunshine duration of 1970s, 1980s, 1990s, and 2000s were $421.7{\pm}18.37hours$, $2,352.4{\pm}15.01hours$, $2,196.3{\pm}12.32hours$, and $2,146.8{\pm}15.37hours$, respectively. The temperature in Middle-Inland zone ($+1.2^{\circ}C$) and Eastern-Southern zone ($+1.1^{\circ}C$) remarkably increased. The temperature increased most in Taebak highly Cold zone ($+364mm$) and Taebak moderately Cold Zone ($+326mm$). The sunshine duration decreased most in Middle-Inland Zone (-995 hours). The temperature (F=2.708, df=3, p= 0.046) and precipitation (F=5.037, df=3, p=0.002) increased significantly among seasons while the sunshine duration decreased significantly(F=26.181, df=3, p<0.0001) among seasons. In further study, it will need to reclassify agro-climatic zone of rice and it will need to conduct studies on safe cropping season, growth and developing of rice, and cultivation management system etc. based on reclassified agro-climatic zone.

A Changes of Traditional Landscape Architecture Materials in Yangdong Village, Gyeongju - Building Roof Materials in the Village Since the 1970s - (정비 사업을 통해 본 경주 양동마을 전통조경 재료의 변화양상 - 1970년대 이후 마을 내 건축물 지붕 소재를 중심으로 -)

  • Kim, Dong-Hyun;Lee, Jong-Sung;Choi, Jong-Hee
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.36 no.4
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    • pp.50-57
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    • 2018
  • Based on research projects and maintenance plans that have been carried out to observe changes in the appearance of buildings in Yangdong Village, Gyeongju, this study analyzed the process of changes in roof materials since the 1970s and drew the following conclusions. First, as the proportion of houses used in the yanggi and yanggi in the 1970s appears similar to that of Wagawa, it is believed that the village landscape has changed due to the use of modern materials by modernization and urbanization. Second, the initial stage of readjustment was designated as a folk data protection zone in 1977 and important folk data designation in 1984. However, due to the lack of a budget for repair and indiscriminate repair, the effectiveness of the project did not seem to have been high. As a result, the trend of decreasing the initial price of the previous period and increasing the use of materials such as yanggi and slate were continuing. Third, in the 1990s, the Cultural Heritage Administration pushed for restoration to the traditional method through extensive renovation projects, making efforts to restore traditional materials, such as reduction of the yanggi and roof, removal of the Hamseok roof, and an increase in the price of grass. Fourth, in the 2000s and thereafter, various readjustment projects were completed in the previous period, with the ratio of Wagwa and Choga greatly increased and the number of houses on the roof of slate reduced by about half, and the level of maintenance of the village's retirement homes was readjusted after the World Heritage List in 2010.

Utilization of Archives in Research on Modern Korean History : Centered on the 1970s (한국현대사 연구에서 아카이브의 이용 1970년대를 중심으로)

  • Kwak, kun-hong
    • The Korean Journal of Archival Studies
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    • no.55
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    • pp.209-233
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    • 2018
  • This article analyzes the cited archives in the research on modern Korean history in the 1970s. The research contains the condition of the citation and the categorization of cited archives by types and topics. The utilization of the archives was insufficient among the entire records, and the citation method was inconsistent. An analysis of archives utilization related to research on modern history should be systematic. The archives should build a database according to archival appraisal and selection, records collection, and archives recollection. Providing the records for the research on modern Korean history is also necessary.

The Development and Historical Character for Structure System with Non-rigid Member (연성구조시스템의 발달과정과 역사적 특성)

  • Lee, Ju-Na;Park, Sun-Woo;Park, Chan-Soo
    • Journal of Korean Association for Spatial Structures
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    • v.4 no.3 s.13
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    • pp.93-101
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    • 2004
  • Structural systems have a lot of architectural meaning concerning historical context of structural technology. Therefore, surveying constructed examples and their constructed year, the character and development of various formations of structure systems with non-rigid member were investigated. At the result, the early modem structure systems with non-rigid member were made up from the cable structures, then membrane structures have mainly used after 1970's. The early structural systems had intended to make the large scale space, after 1970's, they have been adopted into the smaller scale space structure, and cable net structure, pneumatic structure and dome typed hybrid membrane system tend to compose the larger scale spare structure.

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A Study on the play of Allegory in the 1970s - Focusing on Lee Kang-baek's Early Works - (1970년대 알레고리극 희곡 연구 - 이강백의 초기 작품을 중심으로 -)

  • Lee, Jong-Rak
    • Journal of Korea Entertainment Industry Association
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    • v.13 no.6
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    • pp.113-122
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    • 2019
  • In the 1970s, under the tyrannical regulation and censorship of the Yushin regime, realistic dramatization techniques were forced to reveal their limitations. Choosing the 'allegory' technique, a double-meaning narrative structure, Lee Kang-baek sets up virtual spaces or unrealistic figures, both of which lack 'realism'. Lee Kang-baek has allergic the illusion of detadiscourse, the diaspora character, and the universality of 'Political Unconsciousness'. So it's linked to the perception of history in the 1960s. This creates a semantic network of public and casual perception of history. This was a 'bypass' strategy which more clearly disclose the violent politics. Therefore Lee Kang-baek's play shows the desperate situation of the diaspora character being oppressed by detadiscourse, and the desire of the author who can never give up on freedom of expression, though under that oppression. Furthermore, it was an attempt to acquire a timeless universality and symbolism about human freedom and liberation through the Allegory play technique.

Korean National Income Based on a Chain Index: 1953~2010 (연쇄가중법에 의한 한국의 국민소득: 1953~2010)

  • Park, Chang-gui
    • KDI Journal of Economic Policy
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    • v.34 no.3
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    • pp.187-214
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    • 2012
  • Korea's national income statistics have been compiled by the Bank of Korea since 1953. However, there is a break in the time series. The current time series (1970 onward) is based on the '1993 SNA (System of National Accounts)' suggested by the UN, and the previous time series (1953~1970) was based on the '1953 SNA'. The difference between the previous and current time series is 4.8% in 1970 when the two series overlap. The difference is even greater in terms of comparisons across industries. In addition, it has now become even more difficult to connect the current and the previous time series because, in 2009, the Bank of Korea introduced a chain weighted method for calculating the current time series (1970 onward). Under the chain weighted method, the time series underwent substantial modification; for instance, the economic growth rate during 1970~2005 is 0.9%p higher than the rate under the general method. This paper applies chain weighted values and the '1993 SNA' to the previous time series (1953~1970) by utilizing various national account manuals published by the UN and previous Korean input-output tables in order to calculate a long term time series from 1953 to 2010 based on the same criteria as the current time series (1970 onward). In the revised time series, it appears that 1953 GDP at current basic prices is 3.5% higher and the growth rate for the period of 1953~1970 is 1.5%p higher each year than under the previous time series. Under the revised time series the size of the Korean economy as of 2010 is 50-fold bigger than that of 1953. In terms of industries, manufacturing and SOC show significant expansion whereas the extent of that of the service industry is relatively small.

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Hollow Fiber Membrane Bioreactor (실관 막 생물 반응기)

  • Kim, In Ho
    • Applied Chemistry for Engineering
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    • v.5 no.6
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    • pp.911-916
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    • 1994
  • Hollow fiber membrane has been successfully developed as an artificial kidney device in the 1970's. In the early 1970's animal cells were introduced into a hollow fiber membrane cartridge and well propagated in the cartridge. Since then, hollow fiber membrane was utilized as a bioreactor in order to immobilize enzymes as well as to culture microbial cells and plant cells. In this review, the present status and the prospect of hollow fiber membrane bioreactor are investigated in view of cell density and product productivity.

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