• Electrical & Electronic Materials
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• v.6 no.2
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• pp.152-160
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• 1993

MNOS 구조에서 23.angs.의 얇은 산화막을 성장한 후 LPCVD방법으로 S $i_{3}$ $N_{4}$막을 각각 530.angs., 1000.angs. 두께로 달리 증착했을때 비휘발성 기억동작에 미치는 전하주입 및 기억유지 특성을 자동 .DELTA. $V_{FB}$ 측정 시스템을 제작하여 측정하였다. 전하주입 측정은 펄스전압 인가전의 초기 플랫밴드전압 0V.+-.10mV, 펄스폭 100ms 이내로 설정하고 단일 펄스전압을 인가하였다. 기억유지특성은 기억트랩에 전하를 포획시킨 직후 $V_{FB}$ 유지와 0V로 유지한 상태에서 $10^{4}$sec까지 측정하였다. 본 논문에서 유도된 산화막 전계에 대한 터넬확률을 적용한 전하주입 이론식은 실험결과와 잘 일치하였으며 본 해석방법으로 직접기억트랩밀도와 이탈진도수를 동시에 평가할 수 있었다. 기억트랩의 포획전하는 실리콘쪽으로의 역 터넬링으로 인한 조기감쇠가 컸으며 $V_{FB}$ 유지인 상태가 초기 감쇠율이 0V로 유지한 경우 보다 낮았다. 그리고 기억유지특성은 S $i_{3}$ $N_{4}$막의 두께보다 기억트랩밀도의 의존성이 크며 S $i_{3}$ $N_{4}$막두께의 축소로 기록전압을 저전압화시킬 수 있음을 알 수 있었다.

• Animal Systematics, Evolution and Diversity
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• v.13 no.1
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• pp.9-20
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• 1997

한국산 송사리 (Oryzias)속의 송사리 (O. latipes)와 대륙송사리(O. sinensis)의 집단 내 유전적 변이 및 종간 유연관계를 밝히고자 남한의 16개집단과 일본산 송사리(O. latipes) 1개 집단 등 총 17개 집단에 대한 isozyme 분석을 실시하였다. Isozyme 분석 결과 17개의 효소 및 비효소단백질에서 총 32개의 유전자를 검출한 결과, 전체 유전자중 Est-1과 Est-3 는 종 특유의 유전적 표식인자(genetic marker)였다. 송사리집단 중 진도집단의 유전적 변이 가 가장 낮았으며(Ho=0.011, He=0.043), 대륙송사리 서천집단의 유전적 변이가 가장 높았 다.(Ho=0.114, He=0.124). 한국산 송사리 11개 집단의 평균 유전적 변이 정도는 P=12.7%, Ho=0.029, He=0.042, 대륙송사리 5개 집단의 평균 유전적 변이정도는 P=26.3%, Ho=0.082, He=0.097로 각각 나타나 대륙송사리집단의 유전적 변이 정도가 송사리집단에 비해 약 2.5배 정도 높았고 일본산 송사리의 유전적 변이 정도는 P=15.6%, Ho=0.073, He=0.068로 나타났 다. 한국산 송사리와 일본산 송사리와의 유연관계는 S=0.761(D=0.243)로 나타나 유전적으로 뚜렷한 별개의 분류군으로 생각되며, 대륙송사리와 송사리간의 종간 유전적 근연치는 S=0.648(D=0.389)로 일반적인 척추동물의 종간 유전적 분화 수준을 나타냈다.

• Korean Journal of Plant Resources
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• v.1 no.1
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• pp.42-47
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• 1988

The florescence steps of Lycium chinense M. are as follows: Budding-Yellow, leaf-Falling-Flowering. Pruning treatment has a long stem diameter compared withnon-pruning treatment and as a result, the numbers of internode were great and thetotal effective numbers of branch were great, too. In the non-pruning treatment asthe fruit length was short so the fruit was small, and on the contrary in the pruningtreatment as the fruit length was long so large and good fruits were produced.Fresh fruit weight produced per 10a was increased as much as 38-39% in thesurface pruning treatment and in the pruning treatment l0Cm away from surfacecompared with in the non-pruning treatmerlt.

• The Journal of Fisheries Business Administration
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• v.48 no.1
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• pp.73-87
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• 2017

The purpose of this study is to investigate the fishery perception and recreation fishing demand level of coastal waters ranch with the case in Tongyeong city's Bijin-do Yongcho-do, Juk-do. The study conducts a survey of 27 fishermen and 113 recreation fishing tourists from September 26 to November 21, 2016. The major results of this study are as follows. First, the survey of fishery perception level suggests that the increase of fishery resources by Tongyeong-si coastal waters ranch project contributes to the rising income of fishermen, decreased fishing cost, and increased the number of tourists. Second, the survey of recreation fishing tourists's demand level suggests that a beautiful view, fish populations, kindness of residents, fishing point information, charter information, and the convenience of transportation are highly praised and highly regarded. However, links to nearby tourism, lodging facilities, and food information that can increase the income of fishermen is poorly praised. Therefore, this study suggests that a careful marine policy with fishery resource creation should be followed for marine fishing village tourism consumer's benefits in order to increase fishing village's income.

• The Korean Journal of Ecology
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• v.5 no.4
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• pp.164-175
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• 1982

This paper contains the results obtained by the ecological investigation in Bijin island. The investigation was conducted during 3 dyas from Aug. 3 to Aug. 5, 1981. The results are followings. The tracheophyta of this island was recoreded as 64 families, 128 genera, 142 species, 21 varieties and 2 forma. Twenty eight species of ever-green broad-leaved trees comprising Gardenia jasminoides for. grandiflora, Castanopsis cuspidata var. thunbergii, Camellia japonica, etc. wad distributed in the southern area of the island. And there was the wind-break forest mainly consisting of aged Machilus thunbergii, Celtis sinensis and Zelkova serrata in the northern area. The northern area dominated by the second forest of Pinus thunbergii, where the whole residents lead their lives, shows the high population density and pure farming rate, so the natural degree is low. The other hand, there was the well-preserved forest of broad-leaved trees containing Zelkoba serrata. Acer palmatum and Quercus serrata, etc. in southern area having a steep peak, Seonyudai, and no resident. So, the potential vegetation of this island is assumed as the forest of ever-green broad-leaved trees which belongs to the forest of subtropics.

• Applied Chemistry for Engineering
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• v.7 no.5
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• pp.977-984
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• 1996

Liquid-liquid extractions by use of hollow fiber membrane module are fast because of the large surface area per volume. In these membranes, the extractant and feed can be contacted at high speed and two flows are completely independent, so there are no problems with loading and channeling. In this paper, it was investigated the selectivities of extractants for extraction of heavy metals from aqueous solution into organic extractants by using the hollow fiber membrane. To identify the effect of distribution ratio on mass transfer in the membrane, we also compared the distribution ratio with mass transfer coefficient. From these experiments for the system with high distribution ratio, effect of the distribution ratio on mass transfer was weak compare with the low distribution ratio system in the hollow fiber membrane.

• Korea journal of population studies
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• v.29 no.2
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• pp.1-26
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• 2006

This paper examines the interplay among changes in socioeconomic conditions, population policies, and fertility decline during $1960{\sim}2000$ in South Korea. Period-parity-progression-ratios (PPPR) are calculated using 2% samples of Population Census with the implied distribution of completed family size. The total fertility rate based on PPPR declined from 5.21 in 1960 to 2.76 in 1980, and 1.69 in 2000. The family planning programs were successful in meeting the needs of families that wanted to prevent further childbearing after having achieved the desired family size during $1960{\sim}1970$. The 1980s mark two important landmarks: achievement of replacement fertility and emergence of high sex ratio at birth. In the 1990s the "quality and welfare" approach was emphasized. In 2000s, South Korea's fertility is one of the lowest in the world. In response to this, in 2005, the Government adopted a new population policy with the goal of increasing the total fertility level to 1.6 by 2010. The results of this study indicate that proportion of women who would have no children at all throughout their reproductive life span increased substantially from 10% in 1995 to 16% in 2000, with a sharp increase since 1997. Thus, pro-natal programs need to address the problems associated with marriage and having the first child. Towards that, it is important that work and family life become more compatible.

• Korean Journal of Environment and Ecology
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• v.35 no.6
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• pp.621-631
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• 2021

The purpose of this study is to survey and analyze acorn production and characteristics of the Quercus acuta Thunb. according to the need for information on seed supply and seedling cultivation during the restoration of warm broad-leaved forests. For the survey, a total of 30 seed traps with a surface area of 1 m² were set up, 3 in each of 10 quadrats (8 in Wando, 1 in Haenam, and 1 in Jindo). The acorns that fell in the seed trap at the end of each month were collected from August to December each year between 2013 to 2016. The collected acorns were then classified into sound, damaged, decayed, or empty grade, and the number of acorns produced was calculated. In the case of sound acorns, acorn traits, such as length, diameter and weight of acorns without cupule, were measured. Duncan's multiple tests of acorn production and characteristics were conducted for comparative analysis of the annual average values with the values by year, stand, month, and treatment plot. The annual number of acorn dropped into the seed traps in each quadrat from 2013 to 2016 was 5-350 acorns/3 m² in 2013, 17-551 acorns/3 m² in 2014, 5-454 acorns/3 m² in 2015, and 14-705 acorns/3 m² in 2016. There was a large difference in acorn production between the quadrats, presumably attributed to the difference in the amount of light received due to the density of trees in the square. Annual acorn production per area was 335,000 acorns/ha in 2013, 932,000 acorns/ha in 2014, 556,000 acorns/ha in 2015, and 1,037,000 acorns/ha in 2016. That was a sharp variation of acorn production in the two-year cycle. As the fluctuation in the production of Q. acuta showed simultaneity between stands, it is judged that Quercus acuta Thunb. had a clear cycle of fruitfulness and fruitiness between forest objects. September showed the biggest amount of fallen acorns and largest damage from insect pests, indicating that preventing early fall of acorns could increase the fruiting period and enable mass production of sound acorns. There was no significant difference between annual average acorn length in each region. In the case of the acorn diameter and weight, the average values of acorns from Haenam were significantly higher than those from Wando and Jindo. There was no significant difference in the average annual acorn characteristics by month, and the average annual acorn length, diameter, and weight in November were 19.72mm, 12.23mm, and 1.64g, respectively, the highest between August and November.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.4
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• pp.282-290
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• 1992

Based on surplus production models using fishery data for the last 20 years, a stock assessment was conducted for the small yellow croaker in Korean waters. The maximum sustainable yields (MSY) from the Schaefer and Fox models were estimated to be 37,000 metric tons (mt) and 33,450 mt. Zhang's model using time-series biomass with instantaneous coefficients of fishing mortality (F) and using time-series biomass and catch yielded MSY estimates of 45,328 mt and 40,160 mt, respectively. A yield-per-recruit analysis showed that the current yield per recruit of about 20g with F= 1.11 $yr^{-l}$, where the age at first capture $(t_c)$ is 0.604, was much lower than the maximum possible yield per recruit of 43g. Fixing $t_c$ at the current level and reducing fishing intensity (F) from 1.11 $yr^{-l}$ to 0.4 $yr^{-l}$ yielded only a small increase in predicted yield per recruit, from 20 to 25g. However, estimated yield per recruit increased to 43g by increasing $(t_c)$ from the current age (0.604) to age three with F fixed at the current level. This age at first capture corresponded to the optimal length which was obtained from the $F_{0.1}$ method. According to the analysis of stock recovery strategies employing the Zhang model, the optimum equilibrium biomass $(B^*_{MSY})$ which produces the maximum yield could be achieved after approximately five years at the lower fishing intensity (F=0.5).

• KSBB Journal
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• v.18 no.2
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• pp.117-121
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• 2003

The study was carried out to determine the effect of storage property and qualities on soybean sauce and paste by adding different amount of pyroligneous liquor obtained by sujpercritical fluid extraction(SFE). Purified pyroligneous liquor obtained by SFE at 4$0^{\circ}C$/110 bar contained p-cresol, o-cresol and m-cresol food sterilizers, but no toxic substances such as tar, scorched, furfuraland and monophenol. Thus pyroligneous liquor was considered to be suitable as natural food preservative. In case of soybean sauce, pyroligneous liquor was tested to determine the potential of natual food preservative to prevent flim formation on soybean ksauce 15days at 3$0^{\circ}C$. Increasing amounts of purified pyroligneous liquor added to soybean sauce prevented film forming yeasts. In case of paste, pyroligneous liquor was tested to determine the potential of natural food preservative to inhibit browning on paste 60 days at 3$0^{\circ}C$. Purified pyroligneous liquor added to paste inhibited brown pigment. As a result, purified pyroligneous liquor offered a promising way of improving the quality and storage property of soybean sauce and paste.