• The Korean Journal of Quaternary Research
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• v.15 no.1
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• pp.1-12
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• 2001

The time-spatial distributional changes of fourteen warmth-tolerant plants have reconstructed by the use of the historical records of the Chosun Dynasty on the periods of 1454, 1531, 1660, 1760, 1842∼45, 1864, 1907 and 1931. Nine types of geographical distribution, and four types of temporal distribution are, respectively, recognised from fourteen warmth-tolerant plants. The most widely distributed species which occur at more than 100 counties was the persimmon. Species occurred more than 50 counties include the large bamboo, small bamboo and pomegranate. Tea plant and ramie are also commonly found species at more than 30 counties. Past geographical distribution of warmth-tolerant plants seems to be the result of both natural and anthropogenic environments.

• The Korean Journal of Quaternary Research
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• v.18 no.2 s.23
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• pp.105-106
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• 2004

The NDVI(normalized difference vegetation index) dataset is unique or main tool to assess the global, multi seasonal, multi annual, and multi spectral changes over the World. These features are useful for environmental studies in particular, for the vegetation coverage monitoring of the country as Mongolia, where are large pastureland and pastoral animal husbandry, which dependent on natural conditions. Pasture vegetation cover is changing accordingly with both of global climate change and anthropogenic effect or human impacts. Using past 20 years (1982-2001) NDVI derived from NOAA satellite, its dynamical trend has been decreased in all natural zones differently. Also applied the method named "Two Years Differences" which could calculate the number of years with increased or decreased NDVI values at the same place. From May to September have occurred the 9 years maximum decreases of NDVI over Mongolia, but it obtained differently in spatial and temporal scale. In 24.4 ? 32.7% of all territory occurred one year decrease of NDVI and in 18% occurred more than 3 years frequent decrease of NDVI. According to the linear trend of NDVI and in 18% occurred more than 3 years frequent decrease of NDVI dynamics over 69% of whole territory of Mongolia NDVI values had been decreased due to both natural and human induced impacts to the pasture condition. In this paper also included some results of the integrated analyses of NOAA/NDVI and ground truth data over Monglia separately by natural zones.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.4 no.2 s.7
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• pp.67-72
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• 2005

This work proposes a novel coupled line coupler structure based on the asymmetric cascaded connection of coupled lines. The proposed structure can be designed in smaller size than conventional single section coupled line couplers. Also, the additional design freedom offered by the proposed structure can serve many useful purposes such as the output phase control or the flexible coupler layout for complex circuit routing environments.

• Journal of the Korean Society for information Management
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• v.19 no.4
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• pp.53-76
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• 2002

This study compares and analyzes the classes in the major special areas in the sociology, called “branch sociology,” included in the Korean Decimal Classification 4th edition and Dewey Decimal Classification 21st edition. Especially it analyzes the related classes of specified areas (branch sociology) of sociology including those of arts and sports, sciences, languages, society, region, etc. class by class. In this analysis two systems show many differences in the classes included and in the locations of some classes. This analysis can be useful for the future revision of KDC.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.98-105
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• 1989

The examination to find out how the activity of glutamine synthetase (GSA) develop in each wheat leaves during the growth period was carried out. GSA/g FW/leaf were very low at leaf differentiation stage and increased highly several times by unfolding and development of leaf, and declined deeply with the advance of senescence in each leaves. GSA/g FW/leaf were risen gradually from the every lower leaves to the every upper leaves, in consequence activity level and maximum peak per g fresh weight of 7th-flag leaves were two or three times higher than those at the 1st-4th leaves in all of 12 applied nitrogen treatments, thereupon. the highest activities per g fresh weight showed in the 8th leaves. GSA/g FW/leaf was shown two peaks in the 6th-flag leaves and one peak in 1st-4th leaves, respectively. GSA/g FW/leaf (except for senescence leaves) and GSA/plant were increased gradually to the infloresscence emerging stage and were shown the first maximum peak at 13 days before anthesis, then were declined rapidly. to the milk ripe stage (7 days after anthesis). and were shown the second maximum peak at the early dough ripe stage (22 days after anthesis) .

• Research in Plant Disease
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• v.10 no.4
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• pp.297-303
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• 2004

Bacterial blossom blight of kiwifruit (Actinidia deliciosa) has been mainly controlled by antibiotics. Among 15 candidate chemicals, streptomycin sulfate oxytetracycline WP, streptomycin copper hydroxide WP and oxolinic acid WP were selected as preventive bactericides against bacterial blossom blight of kiwfruit through in vitro and in vivo test. Spray of streptomycin sulfate oxytetracycline WP and streptomycin copper hydroxide WP at flowering period was most effective in controlling bacterial blossom blight of kiwifruit. Among the various combinations of spray times at different spray periods, optimum spray program of the preventive bactericides for the control of bacterial blossom blight of kiwifruit was turned out to be 3 times application with 10 day-interval from early May during the flowering season of kiwifruits.

• Journal of Embryo Transfer
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• v.22 no.1
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• pp.69-74
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• 2007

This study was performed to determine the estrous cycles by macroscopic observation of the ovarian changes using the laparoscopy and to make use of these results for embryo transfer in Korean black goat (Copra hircus aegagrus). Laparoscopic examinations of the ovaries were performed from 2 days after $CIDR^(R)$ removal to 22 days after ovulation. The serial morphological changes of follicles and corpus luteum (CL) were observed. CL was classified corpus hemorrhagicum(CH), corpus luteum (CL) and corpus albicans (CA) by its maturation and regression. On the day before ovulation (Day 0), Graafian follicles (GF) were found on one or both ovaries. On the day (Day 1) and $2^{nd}$day (Day 2) of ovulation, and ovulation depression (OD) and an early stage corpus hemorrhagicum $(CH_1)$ were observed at the site of GF, respectively. On Days 3 to 4, more developed and enlarged corpus hemorrhagicum $(CH_2\;and\;CH_3)$ arised from the ovulation of the GF with well vascularization. On Days 5 to 6, it was identified that mature corpus luteum $(CL_3)$ was grown on the ovary, and fully developed CL with adjacent follicles were occupied most part of the ovary on Days 17 and 18. Then the size of CL was diminished, and completely luteal regression $(CL_1\;or\;CA)$ with new large follicle was identified on Days 20 and 22. From these results, the 4 stages of the estrous cycle in Korean black goats were 1) estrus (Day 0) for 1 day, 2) metestrus $(Day\;1{\sim}4)$ for 4 days (stage of CH development), 3) diestrus $(Day\;5{\sim}16/17)$ for 12 or 13 days (luteal stage), and 4) proestrus $(Day\;17/18{\sim}20/22)$ for 4 or 5 days (stage of luteal regression and follicular growing). Laparoscopy for observation of ovarian changes was invasive than laparotomy. Additionally, it had advantages of reduced adhesion and quick operation time. It was considered that laparoscopic examination of ovarian changes will be useful for embryo transfer in the Korean black goats.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.195.2-195.2
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• 2016

대기압 플라즈마는 공기중에서 방전이 가능하고, 이때 생성되는 활성산소종(ROS)과 활성질소종(RNS)을 적절히 이용하면 살균은 물론 제독이 가능하다. 특히 신경작용제나 수포작용제 등의 화학물질은 박테리아 포자, 세균, 바이러스 등의 생물작용제에 비해 더 많은 에너지와 시간이 요구된다. 현재 군이나 의료 시설에서는 과산화수소를 이용한 제독이나 염소계 표백제 성분으로 구성된 수용성 제독제를 이용하지만, 플라즈마의 경우는 단순히 기체를 방전하여 제독에 이용할 수 있으므로 보다 제독 시스템을 간단하게 구성할 수 있다. 하지만 대기압 방전시 방전전압을 낮추기 위해 헬륨과 알곤등의 기체를 공급하여 사용할 경우 부가적인 시스템의 규모가 커져 활용에 제한이 따른다. 따라서 본 연구에서는 대기중에 존재하는 질소, 산소 등을 이온화시키기 위해 10-25kHz의 주파수에서 4.5kV의 8us 펄스전원을 인가하여 공기 플라즈마를 얻고, 열에 의한 분해효과를 제거하기 위해 플라즈마의 기체온도를 20도로 유지시켰다. 플라즈마의 특성은 방출광 분석법을 이용하여 떨림온도를 계산하였고, 질소와 오존의 농도를 동시에 관찰하였다. 분해된 화학작용제는 기체분석기(Gas Chromatography)를 통해 표준 오염농도대비 잔류한 양을 측정함으로써 제독효율을 계산하였다.

• Journal of the Korean Society of Propulsion Engineers
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• v.17 no.4
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• pp.1-9
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• 2013

An active anti-ship missile decoy system was designed conceptually to analyze propulsion system requirements and feasibility to use a liquid bi-propellant rocket engine. Overall mass, size, and shape were assumed referring to specifications of Nulka which was developed by US and Australia in 1990s. The propulsion system was assumed to be a 1,000 N-class $H_2O_2$/kerosene rocket engine with a pressurized feed system. A three-degree-of-freedom optimal trajectory was calculated based on the assumptions, and mass budget was designed from the calculation results. It was found that the requirements for the propulsion system is that it shall be operated more than 100 sec; it shall be re-ignitable; it shall have a throttle capability of a range from 35% to 100% when the maximum thrust at sea level is 1,000 N.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.245-246
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• 2000

산업의 발달로 인하여 유해폐기물의 양과 종류가 날로 증가하고 있다. 특히 본 연구에서 사용한 $CCl_4$는 염화탄화수소(chlorinated hydrocarbons, CHCs)(Elizabeth 와 Catherine) 계통의 대표적인 유해폐기물이며 플라스틱제조업, 제초제와 살충제를 제조하는 농약제조업, 유기용제 제조업 등에서 다량 배출되며 해마다 발생량이 증가하는 추세이다. 최근까지 대부분의 유해폐기물을 처리가격의 저렴성과 기술적으로 어려움이 적은 매립 및 밀봉등의 방법과 물리화학적 방법으로 처리하였으나 앞으로는 소각에 의한 처리방법이 증가되리라 예상된다. (중략)