• Journal of Korean Society of Forest Science
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• v.106 no.3
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• pp.310-319
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• 2017

This study categorized the damaged trees by Supervised Classification using time-series-aerial photographs of Bukhan, Cheonggae and Suri mountains because oak wilt disease seemed to be concentrated in the metropolitan regions. In order to analyze the spatial characteristics of the damaged areas, the geographical characteristics such as elevation and slope were statistically analyzed to confirm their strong correlation. Based on the results from the statistical analysis of Moran's I, we have retrieved the following: (i) the value of Moran's I in Bukhan mountain is estimated to be 0.25, 0.32, and 0.24 in 2009, 2010 and 2012, respectively. (ii) the value of Moran's I in Cheonggye mountain estimated to be 0.26, 0.32 and 0.22 in 2010, 2012 and 2014, respectively and (iii) the value of Moran's I in Suri mountain estimated to be 0.42 and 0.42 in 2012 and 2014. respectively. These numbers suggest that the damaged trees are distributed in clusters. In addition, we conducted hotspot analysis to identify how the damaged tree clusters shift over time and we were able to verify that hotspots move in time series. According to our research outcome from the analysis of the entire hotspot areas (z-score>1.65), there were 80 percent probability of oak wilt disease occurring in the broadleaf or mixed-stand forests with elevation of 200~400 m and slope of 20~40 degrees. This result indicates that oak wilt disease hotspots can occur or shift into areas with the above geographical features or forest conditions. Therefore, this research outcome can be used as a basic resource when predicting the oak wilt disease spread-patterns, and it can also prevent disease and insect pest related harms to assist the policy makers to better implement the necessary solutions.

• The Journal of the Acoustical Society of Korea
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• v.24 no.1
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• pp.1-10
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• 2005

This paper presents a wideband LPA (local polynomial approximation) beamforming algorithm that is appropriate for wideband moving sources. The Proposed wideband LPA algorithm adopts STMV (steered minimum variance) method that utilizes a steered covariance matrix obtained from multiple frequency components in one data snapshot, instead of multiple data snapshots in one frequency bin. The wideband LPA cost function is formed using STMV weight vector. The Proposed algorithm searches for the instantaneous DOA and angular velocity that maximize the wideband LPA cost function. resulting in a higher resolution performance than that of a DS LPA beamforming algorithm. Several simulations using artificial data and sea trial data are used to demonstrate the performance of the Proposed algorithm.

• Journal of Life Science
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• v.22 no.3
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• pp.293-297
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• 2012

The movement of vesicles from the neuronal cell body to specific destinations requires molecular motors. The squid giant axon represents a powerful model for studies of the axonal transport mechanism because the axoplasm can readily be separated from the sheath by simple extrusion. In a previous study, vesicular movements in the axoplasm of the squid giant axon were inhibited by the kinesin antibody. In the present study, we cloned and sequenced the cDNAs for squid brain KIFs. Amplification of the conserved nucleotide sequences of the motor domain by polymerase chain reaction (PCR) using first-strand cDNAs of the squid optic lobe identified six new KIF proteins. Motif analysis of the motor domains revealed that the squid KIFs are homologous to the consensus sequences of the mouse KIFs. The phylogenetic tree generated by using the maximum parsimony (MP) method, the neighbor-joining (NJ) method, the minimum evolution (ME) method, and the maximum likelihood (ML) method showed that squid KIFs are closest to mouse KIFs. These data prove the phylogenetic relationships between squid KIFs and mouse ones.

• Journal of the Korean Applied Science and Technology
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• v.33 no.4
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• pp.634-646
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• 2016

In this work, modified epoxy resins which were well melted in mild solvent were synthesized and solubility assessment was carried out for synthesized epoxy resins. Bisphenol-A type, phenol novolac type and ortho-cresol novolac type epoxy resins were used and fatty acid, dodecyl phenol (DP) and toluene diisocyanate (TDI) were added for synthesis of modified epoxy resins containing fatty acid (MEFA). Composition was epoxy resin/fatty acid = 1.0/0.5 and fatty acid/DP = 0.25/0.25 by equivalent weight and twelve MEFAs were synthesized according to epoxy resins. Viscosity and solubility were measured for twelve MEFAs. As a result, solubility of MEFA was excellent for mild solvent according to increasement of contents of benzene ring, glycidyl group and carbon number of alkyl group. And physical properties were measured for each coating of paints after preparing transparent paints of MEFA to melt well in mild solvent among twelve MEFAs. As a result, they showed an optimal performance on conditions of equivalent ratio of bisphenol-A type epoxy resin/fatty acid/DP/TDI; 1.0/0.25/0.25/0.5 and equivalent ratio of phenol novolac type epoxy resin/fatty acid/DP; 1.0/0.25/0.25 for drying time, adhesion, hardness, impact resistance and alkali resistance.

• Korean Journal of Environment and Ecology
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• v.25 no.5
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• pp.639-648
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• 2011

We recorded the movement of wildbirds nine times at Hoam 1st Tunnel, Kkachisan Park, Deungneung pass to compare the movement between eco-corridor and neighboring crossing road from June to September, 2006. Among three areas, birds did not prefer the eco-corridor at pass type such as Kkachisan Park and Deungneung pass, however number of species and individuals were high at the eco-corridor at Hoam 1st Tunnel. Over 90m width and the slope location of eco-corridors can be beneficial for wild birds to enhance the movement along eco-corridors between isolated two patches. Average foliage volume under two meters showed the relation with bush nesters, and that from 7 to 8m had the highest relationship with canopy nesters. In Seoul city, target species should be considered at the construction of eco-corridors according to site characteristics, but Paradoxornis webbianus could be suggested as a main target species at eco-corridors. To enhance the movement of diverse wildbirds, we would implement that eco-corridors could be located at the slope area with the size of 1ha (over 90m width), eco-corridors could be planted and managed with the high foliage volume of shrub layer under twometers and canopy layer over 8 meters.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.292-292
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• 2017

하천에서 주로 부유사의 형태로 이송되는 유사는 크게 점착성 유사와 비점착성 유사로 구분된다. 입자의 크기가 약 $63{\mu}m$이하인 유사는 입자 표면의 전자기적 점착력의 영향이 우세하여 유사입자들은 지속적인 응집현상을 겪는다. 응집 현상을 통해 유사의 가장 단위인 일차입자(Primary Particle)들은 하나의 커다란 덩어리인 플럭(Floc)을 형성한다. 응집현상이 중요한 이유는 형성된 플럭의 크기 및 밀도가 끊임없이 변화하는 데 있다. 크기와 밀도의 지속적인 변화로 인하여 유사의 부유에 직접적으로 관계하는 침강속도가 변화한다. 우리나라의 금강 및 낙동강의 하구는 점착성 유사가 지배적인 환경으로, 하구에서의 유사 이동을 살펴보기 위해서는 흐름 방향 및 연직방향으로의 흐름 특성(Hydrodynamics)변화와 응집 모형을 통한 응집 현상의 고려가 필수적이다. 이에따라, 본 연구에서는 흐름 방향 및 연직방향으로의 2차원 점착성 유사 이동모형에 관한 개념적 틀(Framework)을 제시한다. 2차원 점착성 유사 이동 모형의 개념적 틀은 기존의 1차원 연직 점착성 유사 이동 모형을 근간으로 한다. 모형에서 흐름을 구성하는 지배 방정식은 오일러-오일러 이상방정식(Eulerian-Eulerian Two-Phase Equation)을 통해 얻는다. 유사상(Sediment Phase, Dispersed Phase)와 유체상(Fluid Phase, Continuous Phase)는 혼합물 이론(Mxiture Theory)를 통해 하나의 혼합물 상(Mixture Phase)의 지배방정식으로 대표된다. 난류의 계산은 와점성 모형 중 -${\varepsilon}$모형을 통해 수행되며, 부유사의 농도는 유사의 이송-확산 방정식을 통해 모의된다. 입력된 흐름 조건을 따라 초기 흐름이 모의되면, 유체 내에서 시간에 따른 플럭의 크기가 계산된다. 플럭의 크기가 계산되는 과정에서 밀도와 침강 속도가 계산되며, 그 이후에 유체 내 유사의 농도가 계산된다. 난류 모의가 수행되고 난 이후에, 유속이 재계산 된다. 이러한 과정을 통해 흐름 방향 및 연직 방향으로의 유사 이동 모의가 가능한 2차원 점착성 유사 이동 모형이 개발될 수 있을 것이라고 생각된다.

• Journal of Life Science
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• v.19 no.1
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• pp.34-39
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• 2009

Alginate with a MW of 1,283 kDa was hydrolyzed with 0.4 M organic acids at $100^{\circ}C$ for 3 hr. Molecular weights of alginates hydrolyzed with organic acids ranged from 7.5 to 53.2 kDa. There was no significant difference in the molar ratio of mannuronate to guluronate in alginates hydrolyzed with organic acids. Acetic add was found to be the most effective organic acid for hydrolysis of alginate. The MW of alginate decreased with increasing concentration and reaction time with acetic acid as a hydrolyzing agent. The correlations between the MW of hydrolyzed alginate and concentration of acetic acid as well as reaction time with 0.4 M acetic acid were plotted and the relevant equations obtained in this study. Polymannuronate and polyguluronate were isolated by pH adjustment of alginate hydrolyzed with 0.4 M acetic add. The molar percentages of mannuronate in polymannuronates isolated from alginate hydrolyzed with 0.4 M acetic acid at $100^{\circ}C$ were increasing in proportional to the reaction time such as 75% for 1 hr, 90% for 3 hr, and 98% for 5 hr of reaction time.

• Journal of Korea Soil Environment Society
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• v.5 no.3
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• pp.55-64
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• 2001

Many organochlorine pesticides are persistent in the environment and have a tendency to bioaccumulate significantly through food chains. Aquatic environments are particularly more affected because the pesticides applied to agriculture systems are eventually carried into water bodies, through surface runoff, rivers, and groundwater flow. The objective of this paper is to study the effect of the coexistence of a heavy metal on the solubility enhancement of the two representative organochlorine pesticides, lindane and dieldrin, by humic acids. The solubility enhancement of pesticides by humic acid in a single system was compared with that in a binary system. The extent of solubility enhancement of lindane by humic acids was constant. while that of dieldrin by humic acids increased. Also, the solubility enhancement of dieldrin by humic acid with Pb decreased than that by humic acid without Pb.

• Journal of Conservation Science
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• v.16 s.16
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• pp.21-26
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• 2004

A lot of waterlogged shrouds and mummies have been found in tombs revered with lime of the Chosun Dynasty(1392-1910) of Korea. Shrouds were heavily polluted with greyish white material. Greyish white material, which adhered to shrouds excavated from tombs(16C and 17C), was submitted to FT-IR qualitative analysis and fatty acid analysis for cleaning. The results of the FT-IR qualitative analysis identified the main ingredient of the greyish white material as calcium salt of fatty acid, including a little of the fatty acids, lipids and proteins. Therefore the greyish white material fumed out adipocere which was formed from the degradation of the lipids in a dead body. From the fatty acid analysis, hydroxy fatty acids(10-Hydroxyhexadecanoic acid and 10-Hydroxyoctadecanoic acid), which were found in adipocere, were detected. The distribution of contents of fatty acids was also rimilar to that of adipocere which have a high proportion of palmitic acid of saturated fatty acid and a low proportion of oleic arid of unsaturated fatty acid. In view of the results of analyses, it was revealed that greyish white material adhered to shrouds was adipocere moved from a mummy.

• Analytical Science and Technology
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• v.13 no.2
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• pp.241-249
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• 2000

In this paper, ozonation of humic acid in water was characterized using $UV_{254}$ absorbance, TOC, Ultra Filtration and $^{13}C-NMR$. Also, carbonyl compounds in ozonated water were analyzed by GC/MS using PFBOA method. Ozonation by-products of water containing humic acid were determined as formaldehyde, acetaldehyde, acetone, glyoxal and methylglyoxal. Results of $UV_{254}$ absorbance and TOC with ozonation time at humic acid 20, 100ppm represent that decrease rate of 80% within ozonation time is 20 min and TOC removal rate of 40-50% within ozonation time is 30 min. Results for $^{13}C-NMR$ and Ultra Filtration, humic acid of high molecular weight by ozonation are oxidated and decomposed so that it was conversed low molecular weight such as aldehydes, carboxylic acid.