• 한국농림기상학회:학술대회논문집
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• 한국농림기상학회 2019년도 하계 학술발표초록집
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• pp.150-150
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• 2019

• Ocean and Polar Research
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• 제23권4호
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• pp.379-388
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• 2001

Ch1 a abundance, Ch1 a-specific productivity and phytoplankton growth rate in each size fraction (pico, $<2{\mu}m$; nano, $2-10{\mu}m$; micro, > $10{\mu}m$) in the waters around the South Shetland Islands (Ant-arctic Peninsula Area) were analysed. Although Ch1 a-specific productivity and growth rate were highest in micro-size fractions, ChI a abundance was highest in pico-size fractions. Selective removal of nano- and micro-size phytoplankton especially by krill and salp grazing, but not limitation of phytoplankton growth, seemed to be the major reason to explain this miss match between productivity and abundance of the phytoplankton community.

• 동아시아경상학회지
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• 제10권4호
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• pp.55-64
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• 2022

Purpose - Corporate reading management requires employees capable of doing their job since employee performance is crucial to the firm's profitability. The objective of this study was to evaluate the positive effects of corporate reading management on employee management. It focuses on factors increasing employee productivity and the impacts corporate management brings about on the overall productivity of any kind of company. Research design, Data, and methodology - The current authors have investigated and conducted the qualitative content analysis (QCA) to obtain the adequate textual dataset in the prior and current literature. One of the primary benefits of doing research using content analysis is that it enables the researcher to employ a combination of qualitative and quantitative research methodologies. Result - Based on the review of the prior literature, the present authors found that there are four corporate reading management solutions to improve employee performance, following those instructions - A. Increased Motivation and Productivity, B. Employee Development, C. Businesses' Objective Alignment, and D. Improved Work Environment. Conclusion - This study addressed and figured out different factors that reading corporate can apply to influence employee performance, thus increasing the company's productivity. Future research should evaluate the adverse effects businesses might face from unfavorable working environments. The research also needed to address how ethics influences employee performance.

• 한국작물학회지
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• 제36권2호
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• pp.112-126
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• 1991

The atmospheric carbon dioxide concentration is ever-increasing and expected to reach about 600 ppmv some time during next century. Such an increase of $CO_2$ may cause a warming of the earth's surface of 1.5 to 4.5$^{\circ}C$, resulting in great changes in natural and agricultural ecosystems. The climatic scenario under doubled $CO_2$ projected by general circulation model of Goddard Institute for Space Studies(GISS) was adopted to evaluate the potential impact of climate change on agroclimatic resources, net primary productivity and rice productivity in Korea. The annual mean temperature was expected to rise by 3.5 to 4.$0^{\circ}C$ and the annual precipitation to vary by -5 to 20% as compared to current normal climate (1951 to 1980), resulting in the increase of possible duration of crop growth(days above 15$^{\circ}C$ in daily mean temperature) by 30 to 50 days and of effective accumulated temperature(EAT=∑Ti, Ti$\geq$1$0^{\circ}C$) by 1200 to 150$0^{\circ}C$. day which roughly corresponds to the shift of its isopleth northward by 300 to 400 km and by 600 to 700 m in altitude. The hydrological condition evaluated by radiative dryness index (RDI =Rn/ $\ell$P) is presumed to change slightly. The net primary productivity under the 2$\times$$CO_2$ climate was estimated to decrease by 3 to 4% when calculated without considering the photosynthesis stimulation due to $CO_2$ enrichment. Empirical crop-weather model was constructed for national rice yield prediction. The rice yields predicted by this model under 2 $\times$ $CO_2$ climatic scenario at the technological level of 1987 were lower by 34-43% than those under current normal climate. The parameters of MACROS, a dynamic simulation model from IRRI, were modified to simulate the growth and development of Korean rice cultivars under current and doubled $CO_2$ climatic condition. When simulated starting seedling emergence of May 10, the rice yield of Hwaseongbyeo(medium maturity) under 2 $\times$ $CO_2$ climate in Suwon showed 37% reduction compared to that under current normal climate. The yield reduction was ascribable mainly to the shortening of vegetative and ripening period due to accelerated development by higher temperature. Any simulated yields when shifted emergence date from April 10 to July 10 with Hwaseongbyeo (medium maturity) and Palgeum (late maturity) under 2 $\times$ $CO_2$ climate did not exceed the yield of Hwaseongbyeo simulated at seedling emergence on May 10 under current climate. The imaginary variety, having the same characteristics as those of Hwaseongbyeo except growth duration of 100 days from seedling emergence to heading, showed 4% increase in yield when simulated at seedling emergence on May 25 producing the highest yield. The simulation revealed that grain yields of rice increase to a greater extent under 2$\times$ $CO_2$-doubled condition than under current atmospheric $CO_2$ concentration as the plant type becomes more erect.

• 한국습지학회지
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• 제9권2호
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• pp.33-43
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• 2007

버드나무속의 분포 현황과 생산성을 조사하여 버드나무속 군집을 보전하고 생태공학적으로 이용하는 데 필요한 기초 자료를 제공하기 위하여 경남 창녕군 우포늪에서 2005년 4월부터 2006년 4월까지 버드나무속의 군집별 분포 면적, 현존식생도, 현존량, 상대생장 및 1차 생산성을 조사하였다. 1. 우포 지역에 분포하는 버들류 7종류 중 선버들이 우점종이고 왕버들이 아우점하였으며, Salix 군락은 선버들, 왕버들, 버드나무, 선버들-왕버들, 왕버들-선버들, 선버들-버드나무 군락 등 총 6종류였다. 2. Salix 군락의 분포 면적은 선버들 군락이 28.46 ha로 가장 넓고, 선버들-왕버들 군락, 왕버들-선버들 군락이 각각 6.12 ha, 선버들-버드나무 군락 2.92 ha, 왕버들 군락 1.86 ha, 버드나무 군락 0.81 ha 등의 순이었다. 3. Salix 군락을 구성하는 선버들은 수령 5~13년, 수고 4.1~7.2 m, DBH 3.0~14.0 cm 등이고, 왕버들은 수령 2~36년, 수고 3.5~10.1 m, DBH 3.2~26 cm 등이었다. 4. 선버들의 현존량은 408 ton 이었으며, 왕버들의 현존량은 336 ton 이었다. 5. 선버들의 연순생산성은 $235g\;m^{-2}yr^{-1}$이고, 이를 우포지역으로 환산한 연순생산량은 $86.4ton\;yr^{-1}$였으며, 왕버들은 $1,006g\;m^{-2}yr^{-1}$ 및 $80.3ton\;yr^{-1}$이었다.

• Asian-Australasian Journal of Animal Sciences
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• 제8권5호
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• pp.505-513
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• 1995

The major factors affecting productivity on daily farms in Queensland, Australia, were determined using the stepwise linear regression approach. The data were obtained from a survey conducted on the total population of daily farms in Queensland in 1987. These data were divided into six major dailying regions. The technique was applied using 12 independent variables believed by a panel of experienced research and extension personnel to exert the most influence on milk production. The regression equations were all significant (p < 0.001) with the percentage coefficients of determination ranging from 62 to 76% for equations developed using' total farm milk: production as the dependent variable. Three of the variables affecting total farm milk: production were found to be common to all six regions. These were; the amount of supplementary energy fed, the area set aside to irrigate winter feed and the size of the area used for dailying. Higher production farms appeared to be more efficient in that they consistently produced milk production levels higher than those estimated from the regression equation for their region. Other methods of analysis including robust regression and non linear regression techniques were unsuccessful in overcoming this problem and allowing development of a model appropriate for farms at all levels of production.

• 생태와환경
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• 제44권4호
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• pp.337-346
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• 2011

We investigated nutrient loading and trophic states in a coastal estuarine system in the Asan estuary by assessing phytoplankton biomass and using the trophic index (TRIX). The monthly and yearly nutrient loading (TN, TP) from freshwater discharge from the Asan and Sapgyo reservoirs into the estuary were estimated and analyzed with related factors. Monitoring data (physio-chemical and biological variables) collected at five estuary stations were used to assess trophic states. Descriptive statistics of total phytoplankton cells, chl a concentrations and primary productivity were also used to assess seasonal trophic status. N loading from freshwater ranged $1.0{\sim}1.3{\times}10^4$ ton yearly. The yearly P loading ranged between 350 and 400 ton during 2004~2006, increasing to 570 ton in 2007. Regression results suggest that DIN and DSi were correlated with freshwater discharge at the upper region. Based on phytoplankton biomass and total cell abundance, the trophic state of the estuary was found to be eutrophic during spring due to phytoplankton bloom. Primary productivity level was remarkably high, especially in summer coinciding with high nutrient loading. Pheopigments increased during warm seasons, i.e. summer and fall. Trophic index results indicate that the trophic state varied between mesotrophic and eutrophic in the estuary water body, especially in the upper region. The results suggest that phytoplankton production was regulated by nutrient loading from freshwater whereas biomass was affected by other properties than nutrient loading in the Asan Estuary ecosystem.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2023년도 학술발표회
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• pp.203-203
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• 2023

총일차생산량(GPP, Gross Primary Productivity)은 생태계의 유기물 생산량을 나타내는 지표로써 생태계 생산성과 안정성을 파악할 수 있는 중요한 지표로 알려져 있다. GPP를 산출하는 대표적인 방법에는 다중 센서를 탑재한 원격 탐사 자료를 활용하는 방법과 플럭스타워를 통해 관측한 에디공분산을 분석하는 방법이 있다. 본 연구에서는 Landsat과 MODIS와 같이 시공간 해상도가 다른 원격 탐사 자료들을 기반으로 초고해상도 GPP 자료를 산출하기 위한 공간자료 융합 연구를 수행하였다. 이를 위해 GAN(Generative Adversarial Networks)과 같은 머신러닝 알고리즘을 활용하였으며 최종적으로 산정된 GPP 정보는 설마천과 청미천 등에 설치된 플럭스타워로부터 획득한 자료와의 비교·검증을 통해 평가되었다. 본 연구의 성과는 향후 증발산 자료, 생태계 호흡량 자료 등과의 조합을 통해 얻을 수 있는 물이용효율(WUE, Water Use Efficiency), 탄소이용효율(CUE, Carbon Uptake Efficiency)과 같은 지표 산정 시 적극 활용될 수 있을 것으로 기대된다.

• 한국패류학회지
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• 제32권2호
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• pp.83-93
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• 2016

For the continuous stable production of oyster, estimation of food availability (F) was carried out in Goseong Bay, south of coast Korea. Primary productivity ranged from 0.07 to $0.44gC/m^2/day$ (average $0.25gC/m^2/day$), lowest in July and highest in January. The distribution of primary productivity at Goseong Bay showed the pattern of "high in the south and low in the north." Food availability (F) was $F{\leq}0$, indicating insufficient food supply, from August to November and F > 0 from January to April. Continuous insufficient food supply was observed at 18 oyster farms in the southern part of the bay and 4 in its northern part. Mortality at the oyster farms was 56% on the average, and around 58% of death occurred during November when food supply was insufficient. The optimal population of cultured oyster per unit flow area was calculated to be $110-115indiv./m^2$ (198-201 indiv./string). When the sea area was divided into 3 regions (A, B, C) according to carrying capacity, the carrying capacity of (A) regions was $52-53indiv./m^2$ (93-95 indiv./string), (B) regions was $142-144indiv./m^2$ (255-259 indiv./string), and (C) regions was $198-202indiv./m^2$ (356-363 indiv./string). In particular, (A) regions showed extremely low productivity. For continuous stable oyster farming at Goseong Bay, it is necessary to control point and non-point source pollution through continuous environmental monitoring and to adjust harvest according to the base carrying capacity during the season of high water temperature.

• The Korean Journal of Ecology
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• 제14권1호
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• pp.63-73
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• 1991

洛東江 河口堰 건설 이후의 干濕地 植生의 변화를 알기 위하여 식생의 분포와 生産性 및 現存量을 조사하여 河口堰 건설 전과 비교한 결과 다음과 같은 결과를 얻었다. 干濕地 I지소의 상부에 草丈이 길고 密度가 높았던 군락(1985.7)이 草丈과 密度가 낮아졌으며, 하부에 개척자 단계의 세모고랭이 군락이 확장되고 密度와 草高 및 現存量이 증가하였다. 干濕地 II지소의 자연제방 부분에 사토가 퇴적되어 확장되고 干濕地面이 높아졌다. 동쪽부분(sandy area)의 세모고랭이 군락은 증가하고 중앙부(muddy area)의 세모고랭이는 쇠퇴되어 現存量이 감소하였다. 서쪽부분의 干濕地(sandy area)는 확장되고, 증가되었다. 河口堰 건설공사 동안 밀도, 초간, 현재량 및 一次純生産量은 심한 변동을 나타내었으며, 공사초기(1984)에 비해 공사 이후 1988년, 1989년의 총현존량(total standing crop)과 괴경의 현존량은 증가하였으나, 1990년에는 1989년보다 약간 감소하였다. 세모고랭이 塊莖의 現存量을 철새들이 도래하기 시작하는 10월을 중심으로 河口堰工事 前(유, 1987)과 河口堰건설 이후를 비교하면 1983년 부터 '84, 85년까지 증가하였으며, 1986년에는 급격히 감소하여 '83년의 81%수준이었다. 완공후의 1988년에는 1983년보다 높은 0.79g DW${\cdot}m^{-2}$으로 83년의 159%로 증가되었으며, '89년에는 폭발적으로 증가하였고 '90년에는 '89년보다 약간 감소하였다.