• Weed & Turfgrass Science
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• 제2권2호
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• pp.122-130
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• 2013

Annual bluegrass는 종자 생산능력이 뛰어나고 한번 조성이 되었을 때 그 분얼경과 지상부 생육이 뛰어나, 전 세계에 가장 널리 퍼져 서식하는 잔디 초종중의 하나이다. 또한 낮은 예초에 적응하는 능력과 조성이 되었을 때 균일성이 좋은 것으로 알려져 있다. Annual bluegrass의 지상부가 성장하기 가장 좋은 온도 범위가 $16-21^{\circ}C$이며 지하부 성장을 위한 최적의 온도범위는 $13-18^{\circ}C$로 고온과 저온에 취약한 초종이다. Annual bluegrass를 관리하기 위해서는 질소와 인산의 비교적 높은 시비량은 annual bluegrass의 확산을 촉진하며 반대로 낮은 시비량은 방제에 도움이 된다. 질소원으로 ammonium sulfate를 사용했을때 sulfate에 의해서 낮아진 토양 pH는 토양속에 존재하는 인이 용해되는 것을 감소시키고 annual bluegrass에 피해를 주는 aluminum의 양을 증가시켜 방제에 효과적이다. 관수는 light and frequent 보다는 deep and infrequent 관수방법이 방제에 도움이 되며 예초높이는 낮추고 예지물은 회수 하는 것이 annual bluegrass의 방제에 도움이 된다. 우리나라에서는 화학적 방제가 주를 이루고 있는데 발아전 처리제로서 prodiamine, bensulide, dithiopyr등이 있으며 발아후 처리제로는 ethofumesate, bisbyribac-sodium 그리고 최근에 연구가 되고 있는 mesotrione등이 있다. 발아전 혹은 발아후 처리제 이외에 생장조절제가 annual bluegrass 방제에 이용이 되고 있는데 paclobutrazol, flurprimidol 등이 있다. 우리나라에서 많이 사용이 되고 있는 생장조절제인 trinexapac은 오히려 여름철 annual bluegrass에 좋은 효과를 나타내고 있어 방제에 적합하지 않다. Annual bluegrass의 방제 효과를 극대화 하기 위해서는 관리적 방제와 화학적 방제의 두 가지 방법이 동시에 고려되어야 할 것이다.

• Journal of the Korean Wood Science and Technology
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• 제52권3호
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• pp.289-299
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• 2024

The current study aimed to investigate the impact of CO₂ enrichment on the width of annual tree rings, earlywood and latewood, and the area of annual growth of Pinus densiflora Siebold & Zucc. grown in open-top chamber (OTC). To this end, two CO₂ enrichment cases were considered, namely 1.4 × increment (560 ppm in OTC-II) and 1.8 × (720 ppm in OTC-III) were compared with the current atmosphere (400 ppm in OTC-I). The CO₂ enrichment conditions for a period of 12 years (2010-2021) were considered, and all measurements were done through image analysis. The study showed that the increment in CO₂ concentrations positively affected the tree growth. The measurement data from the trees in OTC-III were considerably higher than those from OTC-I, whereas those from OTC-II were slightly higher than those from OTC-I. Decreasing patterns of the measured widths and area in 6-7 years after the beginning of CO₂ enrichment was found for all the OTCs. These patterns were possibly due to changes in the physiological features, such as aging. The findings of the present study can have potential uses as fundamental data for forest management considering CO₂ concentrations.

• 경영과학
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• 제34권1호
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• pp.15-25
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• 2017

We evaluated industry growth and employment effects of every possible pairs of 22 manufacturing sectors and 16 regions (i.e, 352 region-sectors). We used annual data of manufacturing sectors from 2008 to 2014 for the evaluation. The evaluation comprises of two steps; We first find several region-sectors that outperform others with respect to the effects of industry growth and employment, which are measured by location quotient analysis, shift share method, employment to GDP ratio and employment elasticity. In addition, cross-efficiency analysis follows to classify region-sector pairs into two sub-categories : efficient region-sectors that deserve to hold the current level of investments and inefficient region-sectors where we should consider efficiency improvements. To examine the efficiency, R&D investment, employment size, and capital investment were used as input factors and production volume, added value, changes in employment size, changes in annual salary per capita were used as output factors. For region-sector pairs that have outstanding growth and employment effects but are inefficient, we employed a CCR DEA model and analyzed how much to adjust the values of input and output factors to improve the efficiency scores. The analysis results showed that inefficiency is mainly due to several factors such as R&D investment, changes in employment size and changes in annual salary per capita.

• 대한치과교정학회지
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• 제4권1호
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• pp.31-40
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• 1974

The age of maximum growth increments-the adolescent spurt-is not only of developmental interest but is used as a marker for timing other growth events. And the mandibular growth rate follows the general growth curve, it is essential for an orthodontist to take the current and exact information about physical growth of patients. The author measured and studied the body height and weight of 11,694 children living in Seoul, and calculated out the mean, standard deviation, coefficient value, annual increments, percentage increments of each value, and made diagram to compare it with others. 1. The growth curve shows linear increment tendency until 17 years of age in male, 15 years in female. 2. The annual increment curves of body height and weight reveals the most peak value in 14-16 years in male and 11-14 years in female. 3. During 11-14 years of age, female growth exceed the male growth in the body height growth. And in weight growth, female growth exceed the male growth during 6-7 years and 11-12 years to show twice crossing. 4. It seemed that until 11-12 years in male and until 9-10 years in female the height growth show the priority to weight growth. And from 17 years in male and 15 years in female the body growth reveals the balanced growth pattern. 5. The time of changes of standard deviation curves of body height and weight coincided with that of annual increments. 6. The prominent high value of body height and weight in the comparison with other data may be due to the secioeconomical and nutritional, environmental influence. 7. The growth accerlation phenomena was detectable.

• 항공우주산업기술동향
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• 제9권1호
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• pp.3-14
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• 2011

인류의 최초 우주 비행으로부터 50년, 최초의 인공위성 발사로부터 54년이 지난 현재 인류의 우주 활동은 어느 때 보다 활발하다. 2000년대 들어 연평균 66회 발사된 우주발사체는 2010년 74회 발사되었으며, 2010년 지구 궤도에서 운행되고 있는 인공위성은 900개에 이르렀다. 우주자산은 국가의 국방 및 안보에 기여할 뿐만 아니라 사회의 경제, 기술 개발에 없어서는 안 되는 필수요소로 자리잡음에 따라 국가가 투자할 가치가 있는 중요 부분이 되었다. 2010년 세계 각국의 우주개발 예산은 715억 달러로 역사상 최대치에 도달하였다. 2002년 이후 세계 우주개발 예산은 연간 8%의 증가율을 보였으나, 2010년 2%로 낮아져 투자 증가율은 다소 둔화되었다. 반면 우리나라의 2011년 정부의 우주개발 예산은 1,825억원으로 2008년 이후 연평균 16%로 감소하였다. 천리안 위성 및 나로호 개발이 완료됨에 따라 개발주기에 따른 예산감소의 영향으로 분석된다. 본 논문에서는 세계 각국 및 우리나라의 우주분야 투자와 우주시장 현황을 정리하였고, 우리나라 예산정책에 관한 시사점을 제고해보았다.

• The Korean Journal of Ecology
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• 제23권2호
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• pp.117-123
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• 2000

Changing patterns and the possibility of climate change in the area of Cheiudo island, the southernmost Island in Korea, were analyzed using daily temperature and Precipitation data observed at the Cheiu Regional Meteorological Office from May 1923 to December 1998. A hydrologic simulation model "BROOK" was used to simulate and analyze the dynamics of daily soil moisture content and soil moisture deficit by applying the daily weather data. During the period, significantly increasing pattern was observed in temperature data of both annual and monthly basis, while no significantly changing pattern was observed in precipitation data. During the last 76 years. mean annual temperature was observed to have risen about 1.4$^{\circ}C$, which may show the Possibility of the initiation of climate change on the island whose validity should be tested in future studies after long-term studies on temperature. Based on the simulation, due to increased temperature, significant increase was predicted in evapotranspiration. while no significant decrease was detected in simulated soil moisture content during the period. Changing pattern of annual soil moisture content was markedly different from those of precipitation. In some dominant trees, negative effects of the drought of the late season for the previous year were shown to be statistically significant to radial growth of the tree for the current year. As annual variation of radial growth of trees is mainly affected by the soil moisture content. the information on the dynamics of soil moisture deficit possibly provides us with useful information for the interpretation of tree growth decline on the mountain. mountain.

• 한국환경복원기술학회지
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• 제22권3호
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• pp.1-14
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• 2019

With a view to developing a database of death years of Korean firs (Abies koreana) at Yeongsil in Mt. Halla and investigating their abrupt inter-annual growth reduction tree-ring analysis was employed. To this end, 10 living trees (YSL) were selected to establish a master chronology and 20 dead trees were used to date their dead years. To investigate the difference in death years by death types, 10 trees, which remained standing (YSSD) out of the 20 dead trees were selected. The rest 10 dead trees were already fallen (YSFD). Two increment cores per tree at breast height were extracted in contour direction using an increment borer. A 106-year master chronology (1911-2016) was successfully established from the 10 YSLs. Through cross-dating between individual YSSD time series and the master chronology, it was verified that 1 YSSD was dead in summer 1978, 1 YSSD between autumn 1999 and spring 2000, 2 YSSDs in summer 2007, 1 YSSD in summer 2010, 1 YSSD in summer 2012, and 1 YSSD in summer 2013. The youngest tree rings of 2 YSSDs having no bark were in 1977 and 2002. For the YSFDs, it was verified that 1 YSFD was dead between autumn 1997 and spring 1998, 1 YSFD between autumn 2001 and spring 2002, 2 YSFDs between autumn 2009 and spring 2010, 1 YSFD in summer 2010, and 2 YSFDs between autumn 2012 and spring 2013, while the youngest tree rings of 2 YSFDs having no bark were in 1989 and 2004. To note, the death years of two trees, one from each death type (YSSD and YSFD), could not be verified due to poor cross-dating with the master chronology. The inter-annual growth reductions of YSSD and YSFD occurred more frequently and intensively than YSL. Typically, the YSFD showed the most frequent and intensive inter-annual growth reduction. On comparing the inter-annual growth reductions with the corresponding records of typhoons however we could not find any reliable relationship. Finally, from prior reports and results of the current study it can be concluded that the death and abrupt growth reduction of korean fir at Yeongsil in Mt. Halla are not caused by only a certain environmental factor but various factors.

• 전기학회논문지
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• 제65권12호
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• pp.1949-1957
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• 2016

Rapid Expansion of EVs(Electric Vehicles) is inevitable trends, to comply with eco-friendly energy paradigm according to Paris Agreement and to solve the environment problems such as global warming. In this paper, we analyze the limit point of transformer acceptable capacity as the increase of power demand considering EVs supply in the near future. Through the analysis of transformer utilization, we suggest methods to analyze the spare capacity of transformer for the case of optimal efficiency operation and emergency operation respectively. We have the results of 18.4~29% spare capacity for the charging infrastructure to the rated capacity of transformer by analyzing the existing sample apartments. It is analyzed that the acceptable number of EVs is 0.09~0.14 for optimal efficiency operation and 0.06~0.13 for emergency operation. Therefore, it is analyzed the power demand of EV will exceed the existing transformer spare capacity in 7~8 years as the annual growth rate of EVs is prospected 112.5% considering current annual growth rate of EVs and the government EV supply policy.

• 항공우주산업기술동향
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• 제7권1호
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• pp.3-10
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• 2009

본 논문에서는 세계 정부의 우주분야 투자와 우주시장 현황을 정리하였다. 1990년대 세계 정부의 총 우주개발 예산은 300~350억불 대에 머물다가 2001년부터 증가한 세계 정부의 우주개발 예산은 2008년 621억불에 도달하여 우주개발 분야 세계 정부 예산이 사상 최대에 도달하였다. 전년 대비 9% 증가한 2008년 세계 정부의 우주개발 예산은 향후 5년간도 증가할 것으로 예상되나 증가율은 4.5%로 둔화될 것으로 전망된다. 2002~2007년간 연 평균 11.5%의 증가율을 보인 세계 우주산업 시장도 2007년 1,230억불로 최대치에 이르렀다. 본 논문에서는 우리나라 정부의 우주분야 투자와 우주산업 시장의 현황을 정리하여 세계 정부 투자 및 세계 우주시장과 비교하였다.

• 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.