• Journal of the Korean association of regional geographers
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• v.6 no.3
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• pp.153-168
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• 2000

An estuarine marsh is semi -inclosed inlets, located between coastal and terrestrial environment. The sediment transport by river and tide through tidal river and vertical accretion by sediment accumulation are important processes in estuarine marsh. An analysis of the vertical accretion rate at various time scale is important work for understanding and managing coastal environments. The purpose of this study is to determin the spatial characteristics of vertical accretion rate in an estuarine marsh, Sunchon Bay, in the southern coastal region of Korean peninsula. The methods of analysis are sedimentation rate by individual tidal cycle, annual accretion rate, concentration of total suspended load in water column. Spatial characteristics of sedimentation rate by individual tidal cycle was investigated using 30 filter paper traps. Sedimentation rate by individual tidal cycle at levee edge was higher than that at back marsh. The sedimentation rate decreased with distance from estuarine front. Levee effect and proximity to the turbidity maximum zone result in a higher sedimentation rate in the levee edge. There is a weak relation-ships between tidal regime and sedimentation rate by individual tidal cycle. Spatial cahracteristics of annual accretion rate was investigared using 30 artificial marker plots. Annual accretion rate at back marsh($1.5{\sim}3.5cm/yr$) was higher than that at tidal river levee edge($0.8{\sim}3.0cm/yr$). Total suspended load (TSL) concentrations in water column also indicate this spatial characteristics of annual accretion rate. TSL concentration in water column leaving the vegetation part dramatically decreased. There is a very strong relationship between the concentration of suspended load and accretion rate. These results indicate that annual accretion rate is controlled by vegetation cover and proximity to the turbidity maximum zone. This difference of spatial characteristics of vertical accretion rate ar various time-scale was due to the fact that surface sediment of levee edge was eroded by tide and other factors. The major findings are as follows. First, the spatial characteristics of vertical accretion rate are different from various time-scale. Second, the major mechanism for the vertical accretion rate in this region is suspended load trapping by vegetation. Third, this region is primarily a depositional regime over the time-scale of the present data Fourth, this estuarine marsh is accreting at rates beyond other area.

• The Optical Journal
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• s.137
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• pp.19-21
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• 2012

2012년 임진년을 맞이하여 정부가 예상하는 경제 성장률은 3.7%이며 2011년의 3.8%에 이어 계속 낮은 경제 성장을 예측하고 있다. 과거 80, 90년대의 높은 경제 성장률 시대는 이미 지나갔고 앞으로는 고용 없는 낮은 성장을 예상하고 있다. 특히 유럽의 재정위기 때문에 2012년에는 불확실성이 증가하고 이에 따라 경제가 더욱 어려울 것으로 예상하고 있으므로 광학산업도 이에 따른 영향을 받을 것으로 예측할 수 있다. 그러면 각 회사들은 이 위기를 어떻게 헤쳐 나가야 하는가? 아마도 현실에 안주하지 않는 도전정신으로 다가 올 경제 위기를 새로운 발전의 기회로 만들기 위해 각 사업체들은 미래를 대비한 다양한 준비를 R&D를 통하여 진행하고 있을 것으로 보인다.

• The Korean Journal of Financial Management
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• v.24 no.1
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• pp.29-58
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• 2007

We develop a model to estimate the value of growth opportunities, which is based on the seminal papers of M&M(1961, 1963) and Lee(2006). Making use of the estimation model, we estimate a new proxy variable of the growth opportunities, other than the usual proxy variables such as quasi Tobin's Q, MBR, and so on. The new proxy variable of growth opportunities can represent a necessary condition to identify whether the increase in new investments are successful or not. The empirical findings on the growth opportunities during the IMF currency crisis period and the post-IMF period are as follows; First, the overall success rate of new investments is as low as 50%, that means only half of the listed firms were increasing new investments when they had the growth opportunities. Second, during the crisis, one third of the listed firms were experiencing negative growth opportunities. However, during the post-IMF period, the growth opportunities on new investments were turned to be positive due to the turnaround efforts of listed firms. Third, the value of intangible assets, which are resulting from the investment of R&D and human capital, are becoming more important than ever. It seems to be true that larger portions of the value of growth opportunities are coming from the intangible assets, not from the increases in new investments of the physical assets.

• 해운
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• s.95
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• pp.17-25
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• 2012

세계경제 둔화에도 국제유가가 상승세로 전환되었다. 국제유가는 2012년 1/4분기에 이란 사태로 인해 급등했다가 2012년 2/4분기에는 유로존 위기 등으로 급락했던 국제유가가 하반기에 들어 상승세로 전환되었다. 그러나 세계경제의 부진이 지속되면서 실물수요 측면의 유가 상승압력은 낮은 수준을 유지한다. IMF 등 주요 기관은 유로존 위기 등으로 세계경제의 회복세가 약화되자 2012년과 2013년 세계경제의 성장률을 하향 조정했다. 특히, 금융위기 발생 이후 세계경제의 버팀목이 되던 신흥국 경제의 성장 둔화가 본격화 되면서 석유 등 실물 수요도 둔화되었다. 2012년 3/4분기 중국의 성장률은 7.4%로 7분기 연속 하락했으며, IMF와 Global Insight는 2012년 중구그이 경제성장률을 각각 7.8%, 7.4%로 전망했다. 다음은 삼성경제연구소가 발표한 "2013 국제유가의 향방"의 주요 내용을 요약 정리한 것이다.

• The Korean Journal of Financial Management
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• v.16 no.1
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• pp.129-153
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• 1999

본 논문에서는 기업의 성장성변수(기업지분의 시장가치 대 장부가치 비율, MB)가 이익반응 계수에 체계적인 영향은 미치는가를 1991년부터 1994년까지 한국증권시장을 대상으로 재무분석가의 예측치에 의한 사건시점방법을 사용하여 실증적으로 분석하였다. 여러 사건시점을 분석한 결과 기업의 성장성과 이익반응계수가 유의적인 정의 관계가 있다는 것을 발견하였다. 이는 우리나라 증권시장에서 성장성이 높은 기업에서의 이익변화가 성장성이 낮은 기업에 비하여 주식수익률에 더 큰 영향을 미친다는 것을 의미한다, 이에 추가로 Skinner와 Sloan(1998)에서 발견된 고성장기업에서 부의 비기대이익에 대한 큰 폭의 주식수익률 하락이 우리나라 시장에서도 나타나는가를 분석하였다. 이들의 결과와는 달리 우리나라 증권시장에서는 이러한 현상이 발견되지 않았으며, 이는 고성장기업에 대하여서도 이익정보가 주식시장에 적절하게 반영된 다는 것을 나타낸다. 본 논문은 우리나라 증권시장에서 기업이익과 수익률간의 사건시점방법을 통한 연구에 있어서 기업의 성장성변수(기업의 시장가치대 장부가치의 비율)가 통제되어야 하는 변수라는 것을 나타낸다.

• 월간 기계설비
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• s.27
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• pp.41-43
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• 1992

대우, 삼성, 현대경제사회연구소 등 국내 민간연구소들이 발표한 $\ulcorner$`93년 경제전망$\lrcorner$ 보고서에 의하면 내년도 우리 경제는 금년과 비슷한 성장률 6$\%$대의 저성장이 계속되고 설비투자 둔화세도 여전할 것으로 보이나 물가와 경상수지 적자는 다소 축소되고 금리수준도 낮아지는 등 경기안정화 추세가 더욱 뚜렷해질 것으로 나타났다. 또한 GNP성장률은 금년도 6.6$\%$(한국은행 전망치)와 같거나 약간 높은 성장을 보일 것이라고 내다봤다.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.573-580
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• 2017

The oxicity assesment of Phenanthrene (PHE) has been investigated by using the rate (r) of survival and population growth in rotifer Brachionus plicatilis. The survival rate was determined after 24 h of exposure to PHE. The survival rate of PHE had no effect at a maximum of $300mg\;L^{-1}$. The r was determined after 72 h of exposure to PHE. It was observed that r in the controls (absence PHE) was greater than 0.5, but that it suddenly decreased with an increased concentration of PHE. PHE reduced r in a dose-dependent manner and a significant reduction occurred at a concentration of greater than $37.5mg\;L^{-1}$. The $EC_{50}$ value of r in PHE exposure was $63.7mg\;L^{-1}$. The no-observed-effect-concentration (NOEC) of r in PHE exposure was $18.8mg\;L^{-1}$. The lowest-observed-effect-concentration (LOEC) of r in the PHE exposure was $37.5mg\;L^{-1}$. From the results, the concentration of PHE (greater than $37.5mg\;L^{-1}$) has a toxic effect on the r of B. plicatilis in natural ecosystems. These results(including NOEC, LOEC and $EC_{50}$) might be useful for the Polycyclic aromatic hydrocarbons(PAHs) toxicity assessment in marine ecosystems.

• Journal of Aquaculture
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• v.3 no.2
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• pp.127-133
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• 1990

Growth Comparisons of two age groups of coho salmon, Oncorhynchus kisutch, underyearling and age one, were made at Chungmu Experimental Fish Culture Station from December 17, 1988 to April 26, 1989. During the first 66 days of experimental period, the fish of underyearling group grew from 167.0 g to 633.1 g in average weight and the feed coefficient (FC) and daily growth rate (DGR) were 1.1 and $2.0\%$, respectively. In the same period, the fish of age one group grew from 396.0 g to 854.6 g in average weight and the FC and DGR were 1.1 and $2.0\%$, respectively. During the second 63 days, the fish of underyearling and age one group grew up to 1171.9 g and 1239.7 g respectively. FCs of these two groups were 1.5 and 2.6, respectively and DGRs were $1.0\%$ and $0.7\%$, respectively. Underyearling fish consumed more feed and performed better FC and DGR than age one fish. FC and DGR sharply decreased as the fish weight increased. Therefore under-yearling fish of this species seems better as seeds for seawater cage culture. For this purpose it is necessary to increase smolting rate in the underyearling group fish within a single season.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.3
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• pp.15-22
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• 2003

The fatigue crack growth model is derived and the retardation model is proposed. The fatigue crack growth model considers the residual plastic stretch on the crack surface which results from the plastic deformation at the tip of fatigue crack. The fatigue crack growth rate is calculated by using the cumulative fatigue damage and plastic strain energy in the material elements at the crack tip. This model gives the crack growth rate in reasonable agreement with test data for aluminum alloy AL6061-T651 and 17-4PH casting steel. The fatigue crack growth retardation model is based on the residual plastic stretch produced from a tensile overload which reduced the plastic strain range of the following load cycles. A strip-yield model of a crack tip plasticity is used for the calculation of a plastic zone size. The proposed retardation model characterized the observed features and delayed retardation of the fatigue crack growth under tensile overload.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.297.1-297.1
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• 2016

높은 굴절률(n_H) 의 ITO films 위에 homoepitaxial 성장 기술로 낮은 굴절률(n_L) 의 ITO를 이중으로 증착한 반사방지막을 연구하였다. 우리는 기판 상에 vapor flux 입사 각도 및 columnar 성장막과 경사각 사이의 상관 관계에 기초하여 낮은 굴절률의 ITO 박막을 Oblique-angle sputtering을 사용하여 증착하였다. Oblique-angle 증착동안 columns 경사각이 incident flux angle 의 증가에 따라 linear 하게 증가했다. 반대로 incident flux angle 이 증가할때 ITO 박막의 굴절률은 현저하게 감소하였는데, 이는 원자의 shadowing effect와 표면 diffusion으로 인하여 필름내의 porosity를 증가시킨 것으로 보여진다. 이러한 결과로 homoepitaxial으로 성장시킨 ITO 이중층 구조 반사방지막 특성이 향상되었으며, 유리 기판 위에서 weight average reflectance가 n_L=1.72, n_H=1.90 에서 6.57%를 달성하였다.