• 한국생태학회:학술대회논문집
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• 한국생태학회 2002년도 VIII 세계생태학대회
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• pp.79-82
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• 2002

Main attackers on pine seeds on the forest floor were investigated in Korea. Damage on pine cones begins in early stage of cone formation, especially by squirrel and Korean squirrel. The above animals left Kayak-like hulls of seed on rocks and fallen tree trunk. Field mice also left the same shape of Kayak-like hulls. But birds including doves and peasants left large shreds with longitudinal cracks or seed cup trace. Most of seeds on the leaf litters as well as under the fallen leaf were consumed by fold mice and birds. Especially fold mice found the seeds under fallen leaves and consumed all of them.

• The Korean Journal of Ecology
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• 제25권4호
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• pp.213-216
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• 2002

Main attackers on pine seeds on the forest floor were investigated in Korea. Damage on pine cones begins in early stage of cone formation, especially by squirrel and Korean squirrel. The above animals left Kayak-like hulls of seed on rocks and fallen tree trunk. Field mice also left the same shape of Kayak-like hulls. But birds including doves and peasants left large shreds with longitudinal cracks or seed cup trace. Most of seeds on the leaf litters as well as under the fallen leaf were consumed by field mice and birds. Especially field mice found the seeds under fallen leaves and consumed all of them.

• 한국토양비료학회지
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• 제38권4호
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• pp.218-221
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• 2005

본 연구는 임산자원과 유실 수자원이 복합적으로 재배되고 있는 방글라데시 Chittagong 지역 경사지 산림토양에서 경제작물인 생강의 재배가능성을 평가하기 위해 수행되었다. 생강의 적정 재식거리를 산정하기위해 총 4개 처리구를 다음과 같이 설치하였다. T1: 100% 채광이 가능한 나대지 (open field), T2: Gamar tree (꾸지나무) 하에서 재식거리 $90{\times}90cm$로 생강재배, T3: Guava tree (구아바 나무) 하에서 재식거리 $180{\times}180cm$로 생강을 재배하였다. 각 처리구는 3반복으로 난괴법에의해 임의배치되었다. 생강의 외관적 생육특성을 비교구 T1과 비교 할 때 Gamar 나무와 Guava 나무하에서 재배된 T2와 T3 처리구에서 양호하였다. 생강뿌리 무게는 수량과 정의 상관관계가 성립하였다. Guava 나무가 재배되고 비교적 재식거리가 크고 ($180{\times}180cm$) 부분적으로 그늘이 형성된 T3 처리구에서 생강수량은 $23.63Mg\;ha^{-1}$로 가장 많았으며, Gamar 나무 하에서 재식거리 $90{\times}90cm$으로 밀식 재배되어 채광이 차단된 조건에서 재배된 T2 처리구의 생강수량은 $15.64Mg\;ha^{-1}$로 가장 낮았다. 결과적으로 생강은 100% 채광조건이나 채광이 완전히 차단된 조건보다는 부분적 차광이 가능한 수종 하에서 재배하는 것이 가장 바람직한 것으로 조사되었다.

• 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.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2008년도 추계종합학술대회 B
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• pp.143-146
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• 2008

RFID 시스템에서 태그의 위치를 추적하기 위해서는 태그의 제적을 모델링하고 색인으로 구성해야 한다. 궤적은 태그가 판독기의 인식영역으로 들어갈 때와 나갈 때 보고되는 두 개의 시공간 위치를 연결한 선분으로 표현될 수 있다. 만약 태그가 판독기의 인식영역에 들어와 나가지 않는 경우에 태그의 궤적은 인식영역에 들어올 때만 보고된 점으로 표현되며, 질의 처리 시 이러한 태그를 찾기 위해 질의영역을 확장해야하는 문제가 발생한다. 이러한 문제를 해결하기 위하여 이 논문에서는 RFID 태그의 제적을 위한 구간 데이터 모델을 정의한다. 또한 구간 데이터 모델에 적합한 R-tree 기반 색인 구조인 IR-tree(Interval R-tree)를 제시하며 효율적인 질의처리를 위해 시간에 종속적인 동적 구간의 특성을 고려한 새로운 삽입 및 분할 알고리즘을 제안한다. 마지막으로 다양한 데이터 집합에서 제안된 색인과 기존 알고리즘을 사용하는 색인과의 성능비교를 통하여 색인의 우수성을 입증한다.

• 농촌계획
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• 제14권1호
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• pp.59-71
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• 2008

The landscape commonly refers to the appearance of the land, including its shape, texture, and colours. Among many factors contributing to the landscape, tree and plants factors playa significant role in rural landscape as a colours. Therefore the rural traditional theme village where had been designated under the rural traditional theme village since 2007 in Naegok-ri, Eohang-myeon, Haman-gun has planned to design the tree plant planning for creating a unique rural landscape. The landscape proposal for the new Rural Village in Naegokri, Yeohang-myeon, Haman-gun suggests three main strategies; 1) The riverside area and reservoir area adjoined forest was required to be prepared to offer organization waterside landscape and forest landscape through landscape planting and selecting trees i.e. able to reflect sense of the season that promote high quality values of landscape area in rural. 2) The area adjoined stable was required to strengthen the screen planting and buffer planting with multiple plant layer structure and trees of branches and leaves closeness, shrubs of beauty flowers in order to improve disamenity landscape and odours. 3) The rural traditional theme village adjoined entrance was required to open space such as multipurpose garden, specialized or themed garden which include Landmark factors and prepared to the space with the various theme and visual diversity in order to take charge of function as landmark characteristic in Naegok-ri, Eohang-myeon, Haman-gun, and so on. In conclusion, this winning principal purpose of this study is applied to basic tree plant model for sustainable rural landscape creation in rural areas by selecting beautiful landscape plants and the tree plant planning.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제6권5호
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• pp.1303-1315
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• 2012

In the draft of the IEEE 802.11s standard, a tree topology is established by the proactive tree-building mode of the Hybrid Wireless Mesh Protocol (HWMP). It is used for cases in which the root station (e.g., gateway) is an end point of the majority of the data connections. In the tree topology, the root or central stations (e.g., parent stations) are connected to the other stations (e.g., leaves) that are one level lower than the central station. Such mesh stations are likely to suffer heavily from contention in bottleneck links when the network has a high traffic load. Moreover, the dependence of the network on such stations is a point of vulnerability. A failure of the central station (e.g., a crash or simply going into sleep mode to save energy) can cripple the whole network in the tree topology. This causes performance degradation for end-to-end transmissions. In a connected mesh topology where the stations having two or more radio links between them are connected in such a way that if a failure subsists in any of the links, the other link could provide the redundancy to the network. We propose a scheme to utilize this characteristic by organizing the network into concentric tiers around the root mesh station. The tier structure facilitates path recovery and congestion control. The resulting mode is referred to as Tier-based Proactive Path Selection Mode (TPPSM). The performance of TPPSM is compared with the proactive tree mode of HWMP. Simulation results show that TPPSM has better performance.

• 공업화학
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• 제22권6호
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• pp.636-641
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• 2011

1990년대 중반부터 지속적으로 산불건수가 증가하고 있으며, 그 규모 또한 대형화 되고 있다. 하지만 이러한 산불의 대형화 추세에도 낙엽, 초본류, 침엽수 및 활엽수에 따른 국 내외에는 수종별 열분해 및 연소 특성에 관한 연구가 미미한 실정이다. 본 논문에서는 국내 산림의 대표적인 침엽수인 적송의 생목과 간벌목을 대상으로 TGA를 이용 열분해 및 연소 특성에 대한 연구를 수행하였다. 적송 생목의 경우 $200^{\circ}C$ 부근에서 발화되고 열분해는 $230^{\circ}C$에서부터 시작되었다. 적송 간벌목의 경우는 발화온도와 열분해 온도가 각각 180와 $205^{\circ}C$부근에서 시작되었다. TGA 분석으로 얻은 실험데이터로부터 열분해반응에서 활성화에너지는 전화율 증가에 따라 증가하였다. 그러나 연소반응에서의 활성화에너지는 감소하는 경향을 나타냈다.

• 정보보호학회논문지
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• 제22권6호
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• pp.1253-1263
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• 2012

그룹응용이 늘어감에 따라 효율적인 인증 그룹 키 합의 프로토콜이 많은 관심을 받고 있다. Lee et al.는 삼진트리 구조와 pairing기반의 암호방식을 가진 트리기반의 그룹 키 합의 프로토콜을 제안했다. 그들의 프로토콜은, 모든 멤버들의 세션랜덤 키를 아는 오직 한 명의 그룹 스폰서가 블라인드 키들을 계산한다. 또, 그 스폰서가 그룹을 떠나면, 트리의 모든 정보가 바뀌어져야 한다. 본 논문에서 제안하는 프로토콜은 여러 명의 스폰서를 두었고, 각 멤버의 비밀정보가 그룹스폰서에게 알려지지 않으므로 그룹스폰서가 떠났을 때, 키 갱신이 Lee et al.의 프로토콜보다 훨씬 효율적이다. 그러므로, 제안된 프로토콜은 동적 피어 그룹에 적합하다.

• Asian-Australasian Journal of Animal Sciences
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• 제16권9호
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• pp.1309-1314
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• 2003

Growth performance, nutrient digestibility and changes in caecal fermentation pattern was studied on four groups of 8 grower rabbits (soviet chinchilla) each, fed on diets containing 17 to 18% CP and $10.4-11.00MJ\;DE\;kg^{-1}$ feed. The complete diets contained mulberry leaves along with other feed ingredients at 0 (LH), 15 (ML15), 30 (ML30) and 45% (ML45) levels. In LH diet ground lucerne hay was added at 15% of the diet as roughage source. The diets were uniform in other nutritional parameters except the higher amount of hemicellulose (18.7 and 16.5%) in LH and ML15 diets. The performance of grower rabbits was better (p<0.05) on LH and ML15 diets in terms of twelve weeks weight (kg), total gain (g), average daily gain (ADG) and feed efficiency (%). Different levels of mulberry leaves in the diet did not influence the dry matter intake. Digestibility of nutrients for DM, OM, CP, NDF and energy was uniform in all the diets but the digestibility of CF, ADF and cellulose was higher (p<0.01) on ML15, ML30 and ML 45 diets. The hemicellulose digestibility was significantly higher (p<0.01) on LH (44.52%) and ML15 (48.00%) compared to ML30 (33.54%) and ML 45 (39.17%) diets. The nitrogen retention (% of intake) was higher (p<0.05) in LH and ML15 diets than ML30 and ML45 diets. The caecum weight as percent of intestine weight consistently increased (p<0.05) with increasing content of mulberry leaves in diets. Total nitrogen and $NH_3$-N was higher on LH and ML15 diets. It is concluded that incorporation of mulberry leaves can replace Lucerne hay in complete rabbit feed (15% in diet). Even at higher level i.e. 30 and 45% of the diet mulberry leaves based complete feed gave promising results.