• Journal of Forest and Environmental Science
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• v.20 no.1
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• pp.40-50
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• 2004

This study was conducted to provide appropriate tending operation strategies for the natural deciduous forest, by the method of evaluating the stand quality, suggesting the removal plan for the undesirable trees, and predicting improvement cutting practice by tree quality evaluation. The results showed that average number of trees per ha was 717 stems, average DBH was 21.1cm. and average height was 13.6m. Canopy dominant species were in the order of Quercus serrata, Q. variabilis, Q. mongolica, Styrax obassia, and Ulmus davidiana var. japonica. Based on grades of four tree form factors for all tree in the study plots, we estimate the change of tree numbers. DBH and height with the improvement cutting by different tree grade. When the higher tree grade was applied to tending operation, the number of stem was decreased, but the values of DBH and height were not changed much, predicted to improve the stand quality.

• Korean Journal of Environment and Ecology
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• v.24 no.4
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• pp.493-499
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• 2010

To obtain the basic data for the conservation and cultivation of major native herb species under the trees, distribution of native herb species, and corrrlations between native herb species and site factors were studied on natural broadleaved forest in Mt. Gariwang and Mt. Jungwang, Pyeunchang-gun. 136 native herb species were distributed in studied area, and the importance percentage of Pseudostellaria heterophylla was proved the highest, 10.8%. The other major herb species were the following oders, Meehania urticifolia, Corydalis remota, Pimpinella brachycarpa, Carex siderosticta, Pseudostellaria palibiniana, Erythronium japonicum, Ligularia fischeri, Asarum heterotropoides var. mandshuricum, Hylomecon vernalis and Astilbe rubra var. rubra. Highly positive correlations were proved Hepatica asiatica and Ainsliaea acerifolia, Pimpinella brachycarpa and Aconitum jaluense subsp. jaluense, Aconitum jaluense subsp. jaluense and Smilacina japonica var. japonica, Meehania urticifolia and Pseudostellaria palibiniana. Seven groups of native herb species were divided by cluster analysis. Preferring site factors for each native herb species were determined. Ligularia fischeri, Ainsliaea acerifolia, Parasenecio auriculata var. matsumurana, Erythronium japonicum and Pimpinella brachycarpa were distributed mainly on the higher sites, Ligularia fischeri were ditributed more frequently in deep soil sites. These results might be useful measures in the conservation and cultivation of native edible and medicinal herb species on the forest floor in the natual broadleaved forest, Pyeungchang-gun.

• Journal of Korean Society of Forest Science
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• v.95 no.1
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• pp.131-138
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• 2006

This study was conducted to assess the diameter growth patterns of Quercus mongolica and Quercus variabilis dominant species in natural deciduous forests in Korea. The diameter growth data were collected from 83 destructively sample trees for stem analysis in Gangwon-Do region. The relationship between diameter growth and 14 tree measurements was also analyzed. The average diameter growth rate of dominant trees for both species increased until ages of 15-20 years, and exhibited generally constant trend for subsequent ages. The diameter growth rate of both species ranged from 0.09-0.83 cm/yr across the all ages. Average annual diameter growth for last 5 measurement years was 0.28 cm/yr for Quercus mongolica and 0.27cm/yr for Quercus variabilis. The observed growth rate decreased with decreasing crown class. The difference between diameter growth rates for different crown classes was only statistically significant (p<0.0001) for Quercus mongolica. Pearson correlation coefficient between the diameter growth rate decreased with relative diameter (r=0.64), relative height (r=0.61), exposed crown area (r=0.58) and total crown area (r=0.56) for Quercus mongolica. For Quercus variabilis, Pearson correlation coefficient decreased with dbh (r=0.57), crown width (r=0.55), age (r=0.39), competition index (r=-0.39), and height (r=0.35).

• Journal of Korean Society of Forest Science
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• v.94 no.6
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• pp.488-495
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• 2005

This study was conducted to understand the influences of forest structure on throughfall, stemflow and interception loss. The study plots included the natural old-growth deciduous, Pinus koraiensis and Abies holophylla forests in Gwangneung and the rehabilitated young mixed forest in Yangju, Gyeonggido. The Pinus koraiensis and Abies hotophylla had been planted in 1976. The rehabilitated young mixed forest had been established to control erosion in 1974. Total and net rainfall were monitored from March, 2003 to October, 2004. Tipping bucket rain gauge recorded total rainfall. Throughfall and stemflow were measured by custom-made tipping bucket and CR10X data logger at each $10m{\times}10m$ plots at intervals of 30 minutes. Interception loss in the Pinus koraiensis plot were most as 37.2% of total rainfall and least as 22.6% in the rehabilitated young mixed forest. Stemflow in the rehabilitated young mixed forest was 10.7% of total rainfall and stemflow in the Pinus koraiensis plot was 2.4%. The average throughfall ratio ranged from 66% to 77% depending on the canopy coverage. The relationship of stemflow and total rainfall represented in a linear regression equation though the variation of data was large. The ratio of stemflow-conversion was 2% of total rainfall in the Pinus koraiensis plot and 12% in the rehabilitated young mixed forest, respectively. The stem storage of the natural old-growth deciduous was the largest of 0.21 mm whereas that of the Pinus koraiensis plot was the least of 0.003 mm. A deciduous forest produced stemflow more than a coniferous forest due to a smooth bark and steeply angled branches. Interception loss of all study plots increased linearly as total rainfall increased. The distribution of interception loss data related in total rainfall became wider in a deciduous forest than a coniferous. It resulted from seasonality of leaf area index in a deciduous forest. As considered above results, it was confirmed that there were great differences of throughfall, stemflow and interception loss depending on forest stand structures. The simulation model for predicting interception loss must have parameters such as forest stand characteristics and LAI in order to describe the influence of forest structure on interception loss.

• Journal of Korean Society of Forest Science
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• v.94 no.6
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• pp.387-396
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• 2005

Having employed the transitional probability model based on Markov chain, the study was carried out to examine successional trends for community types in the natural deciduous forest of Mt. Jumbong. The species composition of oncoming generation in overstory was estimated from that of mid-story, and the species composition in mid-story was based upon that of understory. Successional trend for each community was predicted from the reorganized probability matrix of tree replacement by the square of climax index, which was evaluated by the factors of light absorption, reproduction, and wood quality. As the result of analysis, following table shows the oncoming generation of steady state and dominant species in overstory and mid-story by community types. Even though Acer pseudo-sieboldianum and Carpinus cordata could hardly reach the canopy layer due to the intrinsic growth form, these species were predicted to maintain high compositional ratio so as to play an important ecological role in the study forest ecosystem.

• Journal of Forest and Environmental Science
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• v.21 no.1
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• pp.75-82
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• 2005

The experimental study was carried out to evaluate the performance of underplanted Pinus koraiensis 2-2 seedlings in the closed canopy natural deciduous forest. Overstory density effects on seedling survival and growth were assessed 7 years after underplanting. Seedling survival rate was 80%, average height was 0.9m with minimum of 0.3m and maximum of 2.1m, and average diameter at butt end was 1.7cm with minimum of 1.4cm and maximum of 3.5cm. Compared with the growth rate of the pine plantation after clearcutting, the growth performance of underplanted pine seedlings was so poor that the height growth was less than 30% and diameter growth was less than 20%. Even though the Pinus koraiensis seedlings would be shade tolerant, the establishment and performance of underplanted Pinus koraiensis seedlings could be promoted by more than 50% of canopy regulation that provide adequate light at the forest floor and should exhibit a strong positive response following overstory removal by tending operation.

• Journal of agriculture & life science
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• v.46 no.4
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• pp.41-55
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• 2012

On the basis of vegetation data collected by point-centered quarter method in analysis in Baekdudaegan of Gangwon province in the area of Hyangrobong, Odaesan, Seokbyeongsan, Dutasan, Deokhangsan and Hambaeksan, the study was carried out to classify forest communities and to evaluate the successional trends. The classification method of cluster analysis was used to make various disordered forests into several common groups for 1,004 sample points all together. By clustering the forests in the six study areas were classified into 28 forest communities, which were subjected to aggregate 8 representative forest communities on the count of species composition and species diversity. They were Mesophytic mixed forest community, others deciduous forest community, Quercus mongolica (dominant) community, Q. mongolica (pure) community, Pinus densiflora - Q. mongolica community, P. densiflora community, Betula ermanii community and Q. mongolica - Pinus koraiensis community. The ecological outlook from the result indicated that P. densiflora community and P. densiflora - Q. mongolica community, which were located in Seokbyeongsan, Dutasan and Deokhangsan around 1,000m above the sea level showed lower species diversity index. On the contrary Mesophytic mixed forest community, others deciduous forest community which was located in Hyangrobong, Odaesan and Hambaeksan mostly in protected area and national park around 1,500m above the sea level displayed higher species diversity index. As the composition ratio of Q. mongolica within a certain community was decreased, the species diversity was generally increased, assumed that abundance of Q. mongolica might be negatively associated with species diversity in the national deciduous forest.

• Journal of Korean Society of Forest Science
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• v.88 no.2
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• pp.169-178
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• 1999

The natural regeneration pattern was evaluated for 11 useful hardwood species in the natural deciduous forest where three different silvicultural practices (two-storied system, shelterwood system, and selection system) were applied and passed by three growing seasons. The study forest was presently dominated by Quercus mongolica in the upper canopy. However, since the analysis indicated that the number of regenerated seedlings of Acer mono and Fraxinus rhynchophylla was fairly abundant enough, these two species were anticipated to have the possibility to be among dominant species along with Quercus mongolica. The results of seedling occurrence after regenerating cutting showed that the number of seedlings was estimated for 3,145/ha(10 times of overstory) in the two-storied system, 6,885/ha(9 times of overstory) in the shelterwood system, and 2,275/ha(4 times of overstory) in the selection system. The estimation was varied by species, and the number of stump sprout was more abundant. The proportion of seedlings was high in 60~80% of overstory density and 60~70% of understory coverage, and high in the site of less than $25^{\circ}$ of slope and from southwest to northwest of aspect. These results were still varied by species. Stump diameter and height had little influence on the occurrence of sprout.

• Korean Journal of Environment and Ecology
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• v.29 no.4
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• pp.503-507
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• 2015

To examine the interannual variation of seedfall and seed viability rates of Acer pictum subsp. mono (APSM), we investigated the annual seedfall and seed viability of APSM in the natural broadleaved forest in Mt. Jungwang, Gangwon-do, from 2009 to 2014. The amounts of annual seedfalls from 2009 to 2014 were revealed to be 5,700, 4,060, 60,900, 403,450 and 310 ea/ha respectively. 2013 is presumed to be the masting year since large amounts of seedfall were revealed, compared to that of the other years in the study period. Also, the amount of seeds was significantly different among seed viabilities. Most fallen seeds were damaged or decayed, accounting for 47.88% of the total, followed by empty seeds, undeveloped seeds and sound seeds in that order. The percentage of sound seeds ranged from 6.7 to 31.0%, which marks the lowest average with 16.74%. In the masting year, 2013, a significantly larger number of sound seeds fell at 125,070 ea/ha, on the forest floor than in the other years (320~17,840 ea/ha). Meanwhile, the ratio of damaged or decayed seeds was the lowest at 38%, although the number of those seeds was the largest, 153,310 ea/ha, for the same year. These results imply that the surplus seeds are supplied for natural regeneration in the masting year, supporting the seed predator satiation hypothesis. More long-term researches should be conducted on the seed production of broadleaved trees.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.31 no.7
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• pp.53-64
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• 2002

$CO_2$ 20세기 초 천연 냉매 $CO_2$는 광범위하게 사용되었지만 프레온계 냉매의 출현으로 1940년경부터 $CO_2$냉매는 사용이 제한되었다. 그러나 반 세기 동안 사라졌던 $CO_2$냉매는 1980년 후반에 노르웨이 과학 기술대학 (NTNU)과 북구 최대 민간연구소 (SINTEF)의 Lorentzen 교수에 의해 $CO_2$천연 냉매 사용을 재고하게 되었다. 프레온계 냉매의 환경적 논쟁이 쟁점이 되면서 천연 냉매 사용을 재고하게 되었다. 특히 비가연성과 비유독성으로 인한 $CO_2$냉매가 주목을 받고 있다. 초월임계 사이클레서의 고압 제어에 대한 새로운 개념은 Lorentzen 교수와 동료 연구원에 의해서 특허로 제안되었다. 이에 대한 상업적 권리를 Norsk Hydro사는 1990년에 얻었고,1990년대 초반에 NTNU/SINTEF의 공동 연구개발 프로그램을 통해 기술 경쟁력과 실현 가능성이 검증되었다. 현재 연구소에서는 최초로 초월임계 $CO_2$사이클을 이용한 상업용 온수 열펌프 시스템, 2003년 시작할 연료전지 전기 자동차에 대한 연구를 수행하고 있다. NTNU/SINTEF에서 개발된 $CO_2$기술은 Hydro-SINTEF 공동 벤처 기업인 Shecco기술회사를 통해 제조업자에게 허가된다. 본 고에서는 NTNU/SINTEF에서 수행하였거나 수 중인 과제들을 중심으로 유럽의 $CO_2$시스템의 결과와 주요 개발 범위를 정리하였으며, 특히 작동유체로서의 $CO_2$냉매의 특징을 간단히 설명하고, 온 수 열 펌프, 자동차용 공조기 및 열 펌프, 상업 냉동기 등이 기술되었다. 그 외 압축기 위주의 요소기술 개발에 관한 내용도 기술되었고, 차세대 기술 경향과 전망에 대해서도 제시되었다. 제시되었다.성균 350$\times$$10^4$ CFU균, 방선균 434$\times$$10^4$ CFU균, 진균 676$\times$$10^4$ CFU균으로 진균의 개체수가 비교적 높게 나타났으며, 비산불지역에서는 호기성균 328$\times$$10^4$ CFU균, 방선균 319$\times$$10^4$ CFU균, 진균 461$\times$$10^4$ CFU균으로 진균의 개체수가 높게 나타났다. 토양미생물은 호기성균, 방선균, 진균 모두 비산불지역 보다 산불지역에서 많이 나타났다. 본 조사지역에서 호기성균은 활엽수림보다 침엽수림에서 많게 나타났으며, 방선균과 진균은 침엽수림보다 활엽수림에서 많이 나타났다.효과와 이를 이용한 자기냉동의 방법 그리고 최근에 이루어진 새로운 진전에 대해 소개하고 공기조화 및 냉동분야에의 적용 가능성을 전망해 보고자 한다.및 도입 등 선주들에게 다양한 선박건조자금을 제공하여 내수기반 확충에도 노력해야 할 것 이다.있었다., 인삼이 성장될 때 부분적인 영양상태의 불충분이나 기후 등에 따른 영향을 받을 수 있기 때문에 앞으로 이에 대한 많은 연구가 이루어져야할 것으로 판단된다.태에도 불구하고 [-wh]의미의 겹의문사는 병렬적 관계의 합성어가 아니라 내부구조를 지니지 않은 단순한 단어(minimal $X^{0}$ elements)로 가정한다. 즉, [+wh] 의미의 겹의문사는 동일한 구성요 소를 지닌 병렬적 합성어([$[W1]_{XO-}$ $[W1]_{XO}$ ]$_{XO}$)로 그리고 [-wh] 의미의 겹의문사는 중복된 발은을 지닌 한 단어로 ([W]$_{XO}$ )