• 한국산림과학회지
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• 제99권1호
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• pp.144-152
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• 2010

본 연구는 경기도 광릉시험림에 위치한 노령 느티나무 인공림의 생장특성과 지상부 탄소저쟝량을 구명하기 위해 실시하였다(조사지1:IX영급, 조사지2:VIII영급). 임분구조분석을 위해 수형급을 구분하였고, 수형급별 연륜생장과 우세목의 수간석해를 통해 생장특성을 파악하였다. 직경급은 조사지1에서 8~62 cm, 조사지2에서 14~40 cm의 분포범위를 보였고 수고급은 조사지1에서 8~26 m, 조사지2에서 12~26 m의 분포범위를 보였으며, 이에 따른 수형급간 생장특성이 다르게 나타났다. 그 중 조사지1의 우세목은 최근 5년간 평균 연륜생장량(3.3 mm)이 생장기간 전체의 평균 연륜생장량(2.3 mm)보다 높았고, 조사지2의 우세목은 최근 5년간 평균 연륜생장량(2.2 mm)과 생장기간 전체의 평균 연륜생장량(2.2 mm)이 같았다. 또한, 2개 조사지 모두 우세목과 타 수형급간 연륜생장량의 차이가 큰 것으로 나타났다(p<0.01). 우세목의 수간석해 결과, 단재적이 2개 조사지에서 각각 1.106 $m^3$와 1.035 $m^3$으로 나타나 유사하였으며, 2개 조사지 모두 노령임에도 불구하고 최근에도 연간재적생장량이 지속적으로 증가하였다. 한편, 총탄소저장량은 조사지1에서 65.6 Mg C $ha^{-1}$, 조사지2에서 56.1 Mg C $ha^{-1}$로 나타나 조사지1이 더 많았고, 총탄소저장량에 대한 우세목과 준우세목의 비율이 2개 조사지 모두 90% 이상으로 나타났다. 개체목의 탄소저장량은 2개 조사지 모두 우세목이 가장 많았으나, 우세목의 평균흉고직경 차이로 인해 조사지1의 우세목이 0.054 Mg C $tree^{-1}$정도 더 많았다. 이러한 결과들은 느티나무인공림의 시업적 관리를 위한 기초자료로서 의미가 있을 것으로 사료된다.

• 한국환경복원기술학회지
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• 제22권5호
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• pp.1-12
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• 2019

It is important to measure the height of trees as an essential element for assessing the forest health in urban areas. Therefore, an automated method that can measure the height of individual tree as a three-dimensional forest information is needed in an extensive and dense forest. Since airborne LiDAR dataset is easy to analyze the tree height(z-coordinate) of forests, studies on individual tree height measurement could be performed as an assessment forest health. Especially in urban forests, that adversely affected by habitat fragmentation and isolation. So this study was analyzed to measure the height of individual trees for assessing the urban forests health, Furthermore to identify environmental factors that affect forest growth. The survey was conducted in the Mt. Bongseo located in Seobuk-gu. Cheonan-si(Middle Chungcheong Province). We segment the individual trees on coniferous by automatic method using the airborne LiDAR dataset of the two periods (year of 2016 and 2017) and to find out individual tree growth. Segmentation of individual trees was performed by using the watershed algorithm and the local maximum, and the tree growth was determined by the difference of the tree height according to the two periods. After we clarify the relationship between the environmental factors affecting the tree growth. The tree growth of Mt. Bongseo was about 20cm for a year, and it was analyzed to be lower than 23.9cm/year of the growth of the dominant species, Pinus rigida. This may have an adverse effect on the growth of isolated urban forests. It also determined different trees growth according to age, diameter and density class in the stock map, effective soil depth and drainage grade in the soil map. There was a statistically significant positive correlation between the distance to the road and the solar radiation as an environmental factor affecting the tree growth. Since there is less correlation, it is necessary to determine other influencing factors affecting tree growth in urban forests besides anthropogenic influences. This study is the first data for the analysis of segmentation and the growth of the individual tree, and it can be used as a scientific data of the urban forest health assessment and management.

• Journal of Forest and Environmental Science
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• 제20권1호
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• pp.40-50
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• 2004

이 연구는 강원대학교 학술림내 천연활엽수림을 대상으로 적절한 보육 벌채 시업 방안을 마련하기 위하여 임목의 형질을 평가하고, 형질에 따라 불량한 임목들을 제거하는 벌채 시업 방안을 제시함으로서, 임목형질 평가 방법을 이용한 천연활엽수림의 개선별 시업 적용을 예측하기 위하여 실시되었다. 연구대상 임분의 평균 ha당 본수는 717 본이었으며, 평균직경은 21.1cm, 평균수고는 13.6m로 파악되었다. 상층에는 졸참나무, 굴참나무, 신갈나무, 쪽동백나무, 느릅나무 등의 순으로 우점도가 높은 것으로 나타났다. 4가지의 임목 형질별로 등급을 부여하고, 등급별로 보육 별채를 할 경우마다 단위면적당 임목수, 직경, 수고의 변화를 추정하였다. 형질 등급을 높여서 벌채할수록 임목 본수는 감소하나 임목 형질이 향상되는 효과를 보일 것으로 예상되었다.

• 한국환경과학회지
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• 제16권9호
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• pp.1011-1018
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• 2007

This study was conducted to analysis the ecological characteristics of "Wando HolIy"$(llex{\times}wandoensis)$ which is expecting as a possible ornamental tree with its beautiful leaves, flowers and fruits, and to find special breeding material which have particular characteristics and also provide correct environmental information which are required for commercial cultivation. The hill of Galmoon-Ri, Gunoei-Myon, Jeonnam Province, Korea, were reported as a original habitat of native $llex{\times}wandoensis$. The investigation shows that soil pH of native habitat was 6.18, hardness was 2.39, humidity was 38.6%, direction of slope is SSW, and average inclination was $15^{\circ}. The vegetation around $I.{\times}wandoensis$ is occupied by trees like an Quercus variabilis, Q. serrata, Q. acuta and so on. These are mixed forest of deciduous trees. Tree height reached up to about 12m and its coverage is about 30%. Q. salicina, Camellia japonica, I. integra, Cryptomeria japonica account for sub-tree layer. Tree height is around 8m and coverage is about 20%. Shrub layer was taken by Viburnum furcatum, Callicarpa japonica, Styrax japonica, Eurya japonica, Lindera obtusiloba, Ligustrum japonicum, Smilax china, Cornus walteri etc. Tree height reaches around l.2m and coverage is around 20%. Herb layer includes Trachelospermum asiaticum var. intermedium, Cymbidium goeringii, Dryopteris bissetiana, Disporum viridescens, Disporum smilacinum, Sasa borealis var. gracilis etc. Trachelospermum asiaticum var. intermedium, which are observed in southern evergreen zone, are dominant and its coverage is around 20%. The native habitat was in spoiled condition because of artificial thin out.

• Asian Journal of Atmospheric Environment
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• 제10권1호
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• pp.13-21
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• 2016

The vertical distributions of aerosol extinction coefficient were estimated using the scaling height retrieved at Gwangju, Korea ($35.23^{\circ}N$, $126.84^{\circ}E$) during a spring season (March to May) of 2009. The aerosol scaling heights were calculated on a basis of the aerosol optical depth (AOD) and the surface visibilities. During the observation period, the scaling heights varied between 3.55 km and 0.39 km. The retrieved vertical profiles of extinction coefficient from these scaling heights were compared with extinction profile derived from the Light Detection and Ranging (LIDAR) observation. The retrieve vertical profiles of aerosol extinction coefficient were categorized into three classes according to the values of AODs and the surface visibilities: (Case I) the AODs and the surface visibilities are measured as both high, (Case II) the AODs and the surface visibilities are both lower, and (Others) the others. The averaged scaling heights for the three cases were $3.09{\pm}0.46km$, $0.82{\pm}0.27km$, and $1.46{\pm}0.57km$, respectively. For Case I, differences between the vertical profile retrieved from the scaling height and the LIDAR observation was highest. Because aerosols in Case I are considered as dust-dominant, uplifted dust above planetary boundary layer (PBL) was influenced this discrepancy. However, for the Case II and other cases, the modelled vertical aerosol extinction profiles from the scaling heights are in good agreement with the results from the LIDAR observation. Although limitation in the current modelling of vertical structure of aerosols exists for aerosol layers above PBL, the results are promising to assess aerosol profile without high-cost instruments.

• Journal of Forest and Environmental Science
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• 제31권3호
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• pp.192-201
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• 2015

Information on plant diversity and community structure are required to chalk out necessary actions for conservation management. The present study assessed the composition and diversity of tree species in Kamalachari Natural Forest of Chittagong South Forest Division, Bangladesh, during April 2010 to November 2011. A total of 107 tree species belonging to 72 genera and 37 families were recorded, where Moraceae family was represented by maximum (11) species. Density, Basal area and volume of tree species were $418{\pm}20.09stem/ha$, $21.10{\pm}2.62m^2/ha$ and $417.4{\pm}79.8m^3/ha$ respectively. Diameter and height class distribution of tree species revealed an almost reverse J-shaped curve. Both the number of species and percentage of tree individuals were maximum in the lower DBH and height ranges. Anthropogenic disturbances like illegal tree cutting, over extraction, settlement inside forest area etc. were noticed during the study, which are supposed to cause gradual decrease of both tree species and individuals in the higher DBH and height classes. However, Artocarpus chama was found dominant showing maximum IVI followed by Schima wallichii, Aporosa wallichii, and Lithocarpus acuminata. The quantitative structure of the tree species of Kamalachari natural forest is comparable to other tree species rich tropical natural forests. The findings of the study may help in monitoring future plant population changes of the identified species and adopting species specific conservation programs in Kamalachari natural forest.

• 한국연초학회지
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• 제11권2호
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• pp.157-179
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• 1989

This Study was conducted to estimate the degree of dominance and gene frequency of some sueful characters in tobacco. The eight parents and a set of 28 crosses of F'1s was F'2s were used as materials, and planted on oriental's and burley cultivated system as randomized block designs, respectively. The observed characters were six agronomic characters which were plant height, number of leaves per plant, leaf length, leaf width, days to flowering and yield, and the data obtained from the experiment were analyzed from methods by Hayman's and Jinks. The results obtained are summarized as follows: 1. In Vr-Wr graphical analysis, number of leaves per plant, leaf length, days to flowering and yield were found to be inherited in partial dominance, and plant height was over dominance to be similar to complete dominance, but leaf width was inherited with partial dominance close to complete dominance. 2. In the gene frequency, two varieties Xanthi-Basma and KA 102, for days to flowering and yield had larger number of dominant genes as those were situated near the point of origen. 3. Additive effects of genes(D) were greater than dominance effects of Genes(H) for six agronomic characters except plant height, and mean degree of dominance over all loci was lower than 1 for days to flowering yield, leaf length and number of leaves per plant.

• 한국재료학회지
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• 제5권8호
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• pp.1020-1025
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• 1995

Au/Si(100) Schotty diode를 l00k~300k 온도범위에서 current voltage(I-V), capacitance-voltage(C-V)측정을 하였다. 얻어진 Schottky barrier height(SBH)갑은 실온에서 두측정값 모두 (0.79$\pm$0.02)eV 이다. 그러나 온도가 감소할수록 I-V측정에서 SBH는 선형적으로 감소하고 C-V측정에서 SBH는 온도에 따른 변화가 관찰되지 않았다. 이것은 낮은 온도에서 열이온 방출 이론을 따르지 않는다는 것을 나타낸다. 이것으로 재결합 전류를 고려하여 계산해 본 결과 I-V에서도 SBH의 변화가 관찰되지 않으므로 C-V측정과 일치됨을 보았다. 이런 상반된 결과를 가져오는 이유는 전류수송현상이 온도에 따라 변화하므로 생긴 것임을 알 수 있었다.

• Journal of Industrial and Engineering Chemistry
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• 제68권
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• pp.274-281
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• 2018

Experimental studies of the hydrodynamic performance of the draft tube conical spout-fluid bed (DCSF) were conducted using pharmaceutical pellets. The experiments were carried out in a DCSF consisted of two sections: (a) a conical section with the cross section of $120mm{\times}250mm$ and the height of 270 mm, (b) a cylindrical section with the diameter of 250 mm and the height of 600 mm. The flow characteristics of solids were investigated with a high speed camera and a pezoresistive absolute pressure transducer simultaneously. These characteristics revealed different flow regimes in the DCSF: packed bed at low gas velocities, fluidized bed in draft tube at higher gas velocities until minimum spouting, and spouted bed. The stable spouting was identified by the presence of two dominant frequencies of the power spectrum density of pressure fluctuation signature: (i) the frequency band 6-9 Hz and (ii) the frequency band 12-15 Hz. The pressure drops across the draft tube as well as the annulus measured in order to better recognize the flow structure in the DCSF. It was observed that the pressure drop across the draft tube, the pressure drop across the annulus, and the minimum spouting velocity increase with the increase in the height of draft tube and distance of the entrainment zone, but with the decrease in the distributor hole pitch. Finally, this study provided novel insight into the hydrodynamic of DCSF, particularly minimum spouting and stable spouting in the DCSF which contains valuable information for process design and scale-up of spouted bed equipment.

• 한국자원식물학회지
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• 제11권3호
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• pp.345-352
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• 1998

A Korean endemic and evergreen small tree ' Dendropanax morbifera $L_{EV}$.(Araliaceae)' is a component of evergreen forest and mainly idstributein sourthern region and islands in Korea. A local population of D. morbifera which is located between evergreen and deciduous forest within 50m x 50m quadrate was investigated to ascertain the change of population structure, emergence and growth dynamics of seedlings and saplings, and pattern of spatial distribution by the temproal and spatial expansion of population . The result of analysis of population structure by Importnace Value(IV), evergreen forest showed a high species diversity of evergreen tree species such as Cinnamomum japonicum, Machilus japonica, Neolitsea serica, Daphniphyllum macropodum, Ligustrum japonicum, and etc, in middle and under story than in upper story where Camelia japonica and Quercus acuta were dominant. And in conterminous deciduous fores, the major component of evergreen forest in this region, Camellia japonica, Quercus acuta, evergreen tree of Lauraceae and etc. were abundant in only under story. IV of D. morbifera differed from among three story. In comparative analysis of emergence and growth dynamics of D. morbifera seedlings and saplings between evergreen and deciduous forest, emergece and density of seedlings were significantly greater in evergreen than in deciduous forest, and growth of height and basal diameter of seedlings and saplings were slightly larger in evergreen than in deciduous forest. The spatial distribution patterns by Moristia's index mapping of indivuduals using a lattice method of XY axis within this population showed that seedlings(age up to 2 years) and saplings (age>2 years and height<1m) both evergreen and deciduous forest were more or less aggregated apart from mature trees, and thougth intermediate trees(height>1m and dbh<10cm) had a aggregated distribution pattern, mature trees(dbh>10cm were uniform. In conclusion , the expansion of D. morbfera population from evergreen to deciduous forest accompanied with a mumber of evergreen woody species, and also, emergence and recruitment, and growth of seedlings were greatly influenced moisture and canopy by around community structure.