• 한국조경학회지
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• 제32권4호
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• pp.7-20
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• 2004

This study was executed to find out how to improve the planting and use of landscaping plants in Chuncheon. The number of street trees was 17,877 in 2003. The major species of street trees were Ginkgo biloba(52.7％), Prunus sargentii(15.3％), Zelkova serrata(8.9％), Platanus occidentalis(7.3％). Salix babylonica and Platanus occidentalis were decreased, while Prunus sargentii and Zelkova serrata were increased. Salix babylonica is a good species for a lakeside city, but its seeds cause allergies to some people. Most of the trees have been removed in Chuncheon. The planting of Salix babylonica(♂) resulted in no problems, and it should be propagated to plant. The soil of several areas was analysed to investigate soil conditions. The outskirts of city had good conditions in pH, organic matter and minerals, but the downtown areas had high alkalic, due to alkali from footpath concrete blocks. Appropriate pruning adds to the aesthetic and prolongs the useful life; it also requires less managing of insects and diseases to maintain good healthy of street trees. Street trees were not properly pruned due to electric lines and shortage of pruning information. The pruning was controlled by Korea Electric Power Co, which has no pruning information. Pruning must be maintained by a professional landscape company to maintain good shape such as with Bonsai. The Shrubs planting zone between street trees and other trees, and preservation plates were established for healthy of street trees. They have to be repaired and maintained well to keep better environmental conditions. The number of tree and flower species of 68 schools in Chuncheon were 12 and 16, respectively. The species that showed high preference were Juniperus chinensis, Pinus koraiensis, Pinus densiflora, Rosa centifolia, Forsythia koreana, and Rhododendron schlippenbachii. The high frequency of the protection trees designated by Chuncheon were Pinus densiflora, Ginko biloba, Zelkova serrata, Quercus species. It was thought that the diversification of street tree species, the selection of street trees suitable to each space, the generalization of use of native species, the appropriate pruning and proper fertilization, the control of pests and diseases, and the opinions of citizens concerning landscape plants were needed to improve the planting, use and maintenance of landscaping plants in Chuncheon.

• Journal of applied mathematics & informatics
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• 제5권2호
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• pp.427-432
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• 1998

When an undirected tree T and a vertex ${\gamma}$ in the tree are given the problem to transform T into a rooted tree with ${\gamma}$ as its root is considered. Using Euler tour and prefix sum an optimal algorithm has been developed [2,3]. We will present another parallel algorithm which is optimal also on EREW PRAM. Our approach resuces the given tree step by step by pruning and pointer jumping. That is the tree structure is retained during algorithm processing such that than other tree computations can be carried out in parallel.

• ETRI Journal
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• 제43권6호
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• pp.1024-1037
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• 2021

Mining high utility itemsets (HUIs) from transaction databases considers such factors as the unit profit and quantity of purchased items. Two-phase tree-based algorithms transform a database into compressed tree structures and generate candidate patterns through a recursive pattern-growth procedure. This procedure requires a lot of memory and time to construct conditional pattern trees. To address this issue, this study employs two compressed tree structures, namely, Utility Count Tree and String Utility Tree, to enumerate valid patterns and thus promote fast utility computation. Furthermore, the study presents an algorithm called single-phase utility computation (SPUC) that leverages these two tree structures to mine HUIs in a single phase by incorporating novel pruning strategies. Experiments conducted on both real and synthetic datasets demonstrate the superior performance of SPUC compared with IHUP, UP-Growth, and UP-Growth+algorithms.

• 정보처리학회논문지D
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• 제13D권5호
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• pp.651-660
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• 2006

Apriori 알고리즘에 기반 한 연관 규칙 탐사 알고리즘들은 후보 빈발 항목 집합의 계수 관리를 위한 자료구조로 해시 트리를 사용하고, 많은 시간이 그 해시 트리를 검색하기 위해 소요된다. DHP 연관 규칙 탐사 알고리즘은 해시 트리에 대한 검색 시간을 절약하기 위해 검색 대상인 후보 빈발 항목 집합의 개수를 최대한 줄이고자 노력한다. 이를 위해 사전에 예비 후보 빈발 항목 집합에 대한 간편 계수를 실시한다. 이 때, 예비 계수에 필요한 계산 부담을 줄이기 위해 아주 간단한 직접 해시 테이블 사용을 권고한다. 이 논문에서는 DHP 연관 규칙 탐사 알고리즘의 단계 2에서 사전 전지를 위해 사용되는 직접 해시 테이블 $H_2$와 모든 단계에서 후보 빈발 항목 집합의 계수를 위해 사용되는 해시 트리 $C_k$에 적용될 수 있는 효율적인 해싱 메카니즘을 제안하고 검증한다. 검증 결과 일반적인 단순 제산(mod) 연산 방법을 사용했을 때보다 제안 방법을 적용했을 경우 최대 82.2%, 평균 18.5%의 성능 향상이 얻어지는 것으로 나타났다.

• Spatial Information Research
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• 제19권2호
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• pp.71-76
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• 2011

본 논문에서는 특정 지역의 전력 소비 데이터를 이용하여 safe와 non-safe 전력 부하 라인의 차이를 분석하여 정의하고, 출현패턴을 사용하여 잠재되어 있는 non-safe라인을 식별하기 위하여 제한된 메모리에서 효율적으로 패턴을 찾을 수 있는 TFP-tree 기반의 점진적 출현패턴 마이닝 알고리즘을 제안한다. 특히, 두 개의 다른 최소 지지도 값을 사용하여 전력 소비 데이터와 같은 대용량 데이터에서의 마이닝 문제를 해결한다.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2003년도 춘계학술대회
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• pp.206-213
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• 2003

Application of existing decision tree algorithms for Internet retail customer classification is apt to construct a bushy tree due to imprecise source data. Even excessive analysis may not guarantee the effectiveness of the business although the results are derived from fully detailed segments. Thus, it is necessary to determine the appropriate number of segments with a certain level of abstraction. In this study, we developed a stopping rule that considers the total amount of information gained while generating a rule tree. In addition to forwarding from root to intermediate nodes with a certain level of abstraction, the decision tree is investigated by the backtracking pruning method with misclassification loss information.

• 한국통신학회논문지
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• 제38A권9호
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• pp.782-791
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• 2013

이 논문에서는 적외선 센서를 가진 다수의 감시 로봇에서 획득한 정보를 융합하여 분산되어있는 표적의 위치 좌표를 추정하는 기법을 제안한다. 방위각(azimuth)과 표적을 대응시키는 방법으로 최대-우도(maximum likelihood), 깊이-우선(depth-first), 너비-우선(breadth-first) 트리 탐색(tree search) 기법을 각각 적용하며, 후보선정 및 가지치기(pruning)에 사용하는 정보는 표적의 방위각과 적외선 센서 화면에서 표적의 픽셀 수만을 활용한다. 방위각과 표적이 대응된 후에는 하나의 표적을 가리키는 방위각들에 최소 제곱 오차(least square error) 알고리듬을 적용하여 최적 교점을 구함으로써 표적의 위치 좌표를 추정한다. 제안한 세 가지 탐색 기법 및 위치 추정 기법의 좌표 추정성능, 복잡도, 오차 성능을 모의실험으로 제시하여 성능을 비교한다.

• Molecules and Cells
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• 제22권1호
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• pp.89-96
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• 2006

"Determinate" and "indeterminate" inflorescences in plants are controlled by a single recessive gene, for example, SELF-PRUNING (SP) in Solanum lycopersicum, TERMINAL FLOWER1 in Arabidopsis, CENTRORADIALIS in Antirrhinum, and CENTRORADIALIS-like gene in tobacco. Pepper (Capsicum annuum L.) is an indeterminate species in which shoots grow indefinitely. In this study, we cloned and characterized the pepper SP-like gene (CaSP). RT-PCR revealed that the CaSP transcript accumulates to higher levels in floral buds than in other organs. Comparison of genomic DNA and cDNA sequences from indeterminate and determinate pepper plants revealed the insertion of a single base in the first exon of CaSP in the determinate pepper plants. CaSP is annotated in linkage group 8 (chromosome 6) of the SNU2 pepper genetic map and showed similar synteny to SP in tomato. Transgenic tobacco plants overexpressing CaSP displayed late-flowering phenotypes similar to the phenotypes caused by overexpression of CaSP orthologs in other plants. Collectively, these results suggest that pepper CaSP is an ortholog of SP in tomato.

• Journal of Forest and Environmental Science
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• 제34권2호
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• pp.162-164
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• 2018

This study quantified the carbon storage and uptake by street trees in Seoul and explored suitable planting and management strategies. A systematic sampling model was used to select 50 plots to survey the structures of street trees. The average density and cover of street trees were approximately 5.8 trees/$100m^2$ and 12.1%, respectively. Trees with a dbh of less than 30 cm accounted for about 66.3% of the total number of trees surveyed. The total carbon storage and uptake by the street trees were approximately 103,641 t and 10,992 t/yr, respectively. The total carbon uptake equaled the amount of annual carbon emissions from driving of about 11,000 cars. Street tree planting and management strategies were proposed to enhance carbon uptake. They included multi-layered and multi-aged planting, securing ground and space for plant growth, and avoiding excessive tree pruning.

• 한국경영과학회지
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• 제18권2호
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• pp.183-203
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• 1993

One of the most difficult and time-consuming stages in the development of the knowledge-based system is a knowledge acquisition. A splitting algorithm is developed to infer a rule-tree which can be converted to a rule-typed knowledge. A market segmentation may be performed in order to establish market strategy suitable to each market segment. As the sales data of a product market is probabilistic and noisy, it becomes necessary to prune the rule-tree-at an acceptable level while generating a rule-tree. A splitting algorithm is developed using the pruning measure based on a total amount of information gain and the measure of existing algorithms. A user can easily adjust the size of the resulting rule-tree according to his(her) preferences and problem domains. The algorithm is applied to a market segmentation problem of a medium-large computer market. The algorithm is illustrated step by step with a sales data of a computer market and is analyzed.