• 한국정보과학회논문지:시스템및이론
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• 제32권5호
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• pp.260-267
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• 2005

길이가 n인 알파벳 $\Sigma$상의 텍스트 T에서 패턴 P를 효율적으로 검색하기 위해 접미사 트리와 접미사 배열이 널리 쓰이고 있다. 접미사 배열이 접미사 트리보다 더 적은 공간을 사용하기 때문에 텍스트의 길이가 긴 경우에는 접미사 배열이 더 선호되고 있다. 최근에는 접미사 배열을 이용한 O(${\mid}P{\mid}{\codt}{\mid}{\Sigma}{\mid}) 시간과 O(${\mid}P{\mid}{\codt}log{\mid}{\Sigma}{\mid}$) 시간 검색 알고리즘들이 개발되었다. 본 논문에서는 접미사 배열을 이용한 시간과 공간 효율적인 알고리즘들을 제시한다. 하나의 알고리즘은 O(${\mid}P{\mid}{\codt}{\mid}{\Sigma}{\mid}$) 비트 공간을 사용하여 O(${\mid}P{\mid}$) 시간에 수행되고, 다른 하나는 O($n{\cdot}log{\mid}{\Sigma}{\mid}+{\mid}{\Sigma}{\mid}{\cdot}$nlog log n/logn)비트 공간을 사용하여 O(${\mid}P{\mid}{\codt}log{\mid}{\Sigma}{\mid}$) 시간에 수행되는데, 두 번째 알고리즘은 보다 효율적인 공간을 사용하면서 여전히 빠른 알고리즘이다. 본 논문이 제시하는 알고리즘들이 시간과 공간에 있어 기존의 알고리즘들보다 더 효율적인 알고리즘들임을 실험을 통해 보여주고 있다.

• Journal of Forest and Environmental Science
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• 제36권2호
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• pp.78-90
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• 2020

We studied forest structure and composition in the vicinity of Srinagar Hydroelectric Power Project in Alaknanda Valley, Garhwal Himalaya, India to provide baseline data for the management of forests. Eight sites were selected in the vicinity of power project based on elevation and species composition. Density varied from 650 to 340 ind ha^-1 for trees and from 4,360 to 6,480 ind ha^-1 for shrubs. TBC ranged from 35.02 to 54.02 ㎡ ha^-1 for trees and from 0.875 to 2.628 ㎡ ha^-1 for shrubs. On the basis of density and IVI, Pinus roxburghii was found dominant tree species in most of the sites, whereas among the shrubs, Carissa opaca was dominant. Dominance of Pinus roxburghii in most of the sites is an indication towards possible threat to associated species in the area. The dominance-diversity curve of trees showed a geometric distribution, whereas the shrubs displayed log-normal curves. The forest has rich and diverse species composition however; habitat degradation caused by the construction of Power Project might lead to reduction of plant species from the area. The information obtained from this study will be helpful in predicting possible changes in the forest ecosystem properties in near future after completion of the power project.

• 한국환경과학회지
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• 제15권7호
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• pp.615-622
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• 2006

The purpose of this study was to analyze the village groves in Pohang city by classifying them into 5 categories: sage plantation, shelter-belt plantation, shore plantation, ornamental plantation and bower plantation. The results of this study can be summarized as follows; The village groves in Pohang city consist of 16 sage plantations ($128,682m^2$), 14 shelter-belt plantations ($807,755 m^2$), 17 shore plantations ($447,616m^2$), 10 ornamental plantations ($141,276m^2$) and 6 bower plantations ($79,075 m^2$). Namely, the ratio of shore plantations is highest (n=17) in terms of number, while that of shelter-belt plantations is highest (50.3%) in terms of area. On the other hand, Pinus Thunbergii account for the absolute majority (n=55,239, 74.1 %) of the trees, followed by pine trees (n=18,017, 24.2%). Both species are combined to account for 98.3% of the entire trees, which means that the plantations are simple in terms of tree species When the village groves were compared in terms of functional age, sage plantations are oldest or aged 143 years, followed by bower plantations (aged 137), ornamental plantations (aged 118), shore plantations (aged 92) and shelter-belt plantations (aged 88).

• 한국산림과학회지
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• 제108권2호
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• pp.139-146
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• 2019

This study was conducted to determine the carbon (C) and nitrogen (N) distribution within tree components (i.e., stem, branches, leaves, and roots) of the Japanese larch (Larix kaempferi Carriere) plantation and natural oriental cork oak (Quercus variabilis Blume) stands. Fifteen Japanese larch and 15 oriental cork oak trees were destructively sampled to compare the C and N stocks in the components of the trees from three different regions-Hadong-gun, Hamyang-gun and Sancheong-gun-in Gyeongnam Province, South Korea. Species-specific allometric equations were developed to estimate the C and N contents in the tree components based on the diameter at breast height (DBH). There were differences in mean C and N concentrations between the Japanese larch and the oriental cork oak. The mean C concentrations of the tree componentswere significantly higher in Japanese larch than in oriental cork oak; whereas, the N concentration in the stems was significantly lower in Japanese larch than in oriental cork oak. The allometric equations developed for C and N content were significant (p < 0.05) with a coefficient of determination ($R^2$) of 0.76 to 0.99. The C and N stocks in the tree components do not appear to be affected by the species such as Japanese larch plantations and oriental cork oak stands. This study emphasizes the importance of C and N concentrations to estimate the C and N distribution according to tree components in different tree species.

• Journal of Forest and Environmental Science
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• 제33권4호
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• pp.270-280
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• 2017

Selection of superior phenotypes of fruit trees and products based on established criteria by local people is a prerequisite for future species domestication and conservation. Thus the study objective was to identify the local people's perceptions and preferences on baobab trees and products. A sample of 142 respondents was randomly selected using structured interviews in Blue Nile and North Kordofan, Sudan in 2013. Descriptive analysis was employed using SPSS and Excel programs. The study results indicated that local people use the morphological characteristics of the tree (leaves, fruits, seeds, kernels and bark) to differentiate individual trees. Based on the perceptions, local people recorded trees with delicious leaves, white pulp color, big fruit size and mature capsule size, and high pulp yield as criteria for differentiating between baobab trees in the study areas. In contrast, the undesirable traits were connected to trees with acidic pulp, slimy pulp, bitter leaves, and low pulp yield. The study concluded that the ethnobotanical knowledge of the baobab tree and its products may play an important role in tree domestication and improvement in Sudan. However, further research on tree genetics is needed to complement the ethnobotanical knowledge for baobab resources domestication and conservation.

• 한국전산응용수학회:학술대회논문집
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• 한국전산응용수학회 2003년도 KSCAM 학술발표회 프로그램 및 초록집
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• pp.16.1-16
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• 2003

A subset S of vertices of a graph G is independent if no two vertices of S are adjacent by an edge in G. Also we say that S is maximal independent if it is contained In no larger independent set in G. A planted plane tree is a tree that is embedded in the plane and rooted at an end-vertex. A (k＋1) -valent tree is a planted plane tree in which each vertex has degree one or (k＋1). We classify maximal independent sets of (k＋1) -valent trees into two groups, namely, type A and type B maximal independent sets and consider specific independent sets of these trees. We study relations among these three types of independent sets. Using the relations, we count the number of all maximal independent sets of (k＋1) -valent trees with n vertices of degree (k＋1).

• 한국토양비료학회지
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• 제32권2호
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• pp.132-139
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• 1999

요소 엽면시비가 온주밀감 잎의 질소함량 수체 및 토양의 질소회수율에 미치는 영향을 구명하고자 1998년 7년생 흥진조생에 질소 기준량 표충시비($124kg\;ha^{-1}yr^{-1}$, 나무당 86 g). 기준량의 50% 엽면시비($62kg\;ha^{-1}yr^{-1}$), 나무당 43 g), 기준량의 25% 엽면시비($31kg\;ha^{-1}yr^{-1}$, 나무당 22 g)처리를 두고 봄 여름, 가을 비료로 56(2반복 $^{15}N$ 표지 요소, 5반복 일반 요소), 11((2반복 $^{15}N$ 표지 요소, 5반복 일반 요소). 33%(7반복 모두 일반 요소) 비율로 분시하여 시험한 결과를 요약하면 다음과 같다. 나무(본)당 과실수량 및 품질은 처리간 유의한 차이가 없었다 당년 봄순의 엽신의 전질소함량은 9월 상순까지는 엽면시비구에서 많았으나 11월 16일(수확기)이후에는 처리간 큰 차이가 없었다. 수체(樹體)에 의한 질소회수율은 어느 수체 부위에서나 25% 엽면시비구에서 가장 높았고, 50% 엽면시비구에서 다음으로 높았다. 수체 전체의 질소회수율은 25, 50% 엽면시비구, 표층시비구에서 각각 29.2, 17.7, 8.0%이었다. 봄과 여름에 시용된 질소의 토심 0~40 cm에서의 잔류율은 25, 50% 엽면시비구 표층시비구에서 각각 50.3, 45.6, 51.8%이었다. 전체(수체, 낙엽, 잡초, 토양) 회수율은 25, 50% 엽면시비구, 표층시비구에서 각각 81.8, 65.1, 60.6%이었다.

• 한국컴퓨터정보학회논문지
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• 제19권2호
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• pp.143-150
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• 2014

본 논문에서는 트리에서의 배달문제를 제안하고, 이를 해결하는 두 개의 알고리즘을 제안한다. 트리상에서의 배달문제는 n개의 서로 다른 이동속도를 갖는 로봇을 이용하여 배달물을 트리의 한 노드에서 다른 노드로 배달하는 시간을 최소화 하는 문제이다. 첫 번째 알고리즘은 핸드오버가 발생하는 장소에 대한 제한을 두어 트리에서의 배달문제를 위한 최적해를 생성한다. 이 알고리즘에서 핸드오버는 주어진 트리의 정점에서만 발생하는 것으로 가정하며, 시작점에서 도착점까지 핸드오버가 발생하는 위치와 핸드오버에 참여하는 로봇의 색인을 순서대로 찾는 방법으로 문제를 해결한다. 두 번째 알고리즘은 첫 번째 알고리즘을 확장하여 핸드오버 장소에 대한 제약을 제거하며, 여전히 최적해를 생성한다. n을 로봇의 수라 하고, m을 트리의 노드 수라 할 때 두 개의 알고리즘은 모두 $O((n+m)^2)$ 시간복잡도를 갖는다.

• 한국유기농업학회지
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• 제18권2호
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• pp.245-255
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• 2010

본 연구는 여러 유기질 비료와 멀칭자재에 따른 MM.106 사과 대목의 생장과 광합성 동화량에 미치는 영향을 구명하기 위해서 수행되었다. 유기질 비료와 멀칭 자재의 무기성분 함량과 탄소/질소 비율(탄질비)은 수체 생육과 광합성에 영향을 주었다. 미생물이 유기태질소를 무기태로 전환하기 용이한 이상적인 탄질 비를 나타냈던, 상업용 유기질 비료, 계분, 식물성 퇴비, 그리고 풀 멀칭구가 줄기생장과 SPAD 및 광합성 함량을 증가시켰다. 처리 5주 후에 SPAD 및 광합성 함량이 처리구에 의해 영향을 받았으며, 처리 6주 후에 줄기생장 또한 처리구 간에 유의성을 나타냈다. 토양 내 무기태 질소 함량이 $10{\sim}15mg{\cdot}kg^{-1}$이었을 때 가장 효율적인 수체 생장과 발달을 나타냈으며, 질소함량은 생장과 발달에 유의적인 상관관계를 나타냈다.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제4권1호
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• pp.28-42
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• 2023

Seed dispersal supports community structure, maintains genetic connectivity across fragmented landscapes, and influences vegetation assemblages. In the Philippines, only two seed dispersal studies have compared different dispersal agents. We examined the seed dispersal patterns of water, wind, birds, and bats in the Caliraya Watershed, Philippines. We aimed to determine the floral species that were dispersed and how the forest characteristics influenced seed dispersal. By running seed rain traps and drift litter collection from March to June 2022, we analyzed 14,090 seeds in a privately owned study site within the watershed. Water did not exclusively disperse any species and acted as a secondary disperser. Seed density (seeds/trap) was significantly higher for bird-dispersed (n=166) and bat-dispersed (n=145) seeds than for wind-dispersed (n=79) seeds (One-way analysis of variance [ANOVA]: F_2,87=16.21, P<0.0001). Species number (species/trap) was significantly higher for bird-dispersed (n=3.7) and bat-dispersed (n=3.9) seeds than for wind-dispersed (n=0.2) seeds (One-way ANOVA: F_2,87 =16.67, P<0.0001). Birds dispersed more species because they are more diverse and access a wider variety of fruits, unlike bats. Birds and bats target different fruits and provide separate seed dispersal services. Generalized linear model analyses revealed that the number and basal area of fleshy fruit trees most strongly influenced the bird seed dispersal patterns. Therefore, we recommend a three-way approach to restoration efforts in the Caliraya Watershed: (1) ensure the presence of fleshy fruit trees in restoration zones, (2) assist the establishment of mid-successional and wind-dispersed trees, and (3) intensify the conservation efforts for both flora and faunal diversity.