• Journal of Forest and Environmental Science
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• 제38권3호
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• pp.174-183
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• 2022

The study aims to examine population indices of mature trees in Jebel Elgarrie forest, Blue Nile State, Sudan. We used remote sensing techniques to stratify the forest into vegetation classes depending on tree density. We distributed 97 circular sample plots (0.1 ha) proportionally to the area of the vegetation classes. In each sample plot we identified, counted and recorded all mature trees (DBH ≥10 cm). We calculated frequency, density, abundance, richness, evenness and diversity for each species and we drew abundance rank curve of mature trees. We used One-Way ANOVA to test for differences (α=0.05) in mean density (No./ha) of mature trees between vegetation classes. Results revealed that the forest was conveniently sub-divided into high density (C1), medium density (C2), low density (C3) and bare farm land (C4) classes. We identified fifteen tree species that belong to 10 families and 14 genera. Combretaceae and Fabaceae were the common families while Anogeissus leiocarpa was the most frequently occurring species. While species diversity varied between vegetation classes, diversity of the forest as a whole is low. While mean density of mature trees in C1, C2, C3 and C4 it was 100, 74, 10, and 0, respectively, it was 54 for the whole forest indicating low stocking, Following One-Way ANOVA, multiple comparisons revealed significant differences in mean density of mature trees between C1 & C3 and C2 & C3. The study provided empirical results on population indices of mature tree species, which would be of importance for successful management and conservation of the forest.

• 한국환경과학회지
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• 제19권3호
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• pp.305-312
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• 2010

The purpose of this study is to compare the relative growth of annual ring width of red pine(Pinus densiflora), black pine(Pinus thunbergii) and pitch pine(Pinus rigida) by means of multiple regression method according to Graybill hypothesis. The obtained results are as follows. 1. The changes of rainfall have affected to tree growth during the periods of 1975 through 1978. 2. Among these pine trees, red pine was mostly influenced by environmental factors. 3. The growth of annual ring width was sensitively responded to the changes of rainfall and air temperature. 4. Among the heavy metals analyzed, the concentrations(ppm) of Lead(Pb) and Copper(Cu) were negatively effected on the growth of annual ring width of pine trees. 5. The analytical technique of annual ring width may be useful for estimation of the pollution in forest areas near industrial complexes.

• Communications for Statistical Applications and Methods
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• 제10권3호
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• pp.971-980
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• 2003

The tree method can be extended to multivariate responses, such as repeated measure and longitudinal data, by modifying the split function so as to accommodate multiple responses. Recently, some decision trees for multiple responses have been constructed by Segal (1992) and Zhang (1998). Segal suggested a tree can analyze continuous longitudinal response using Mahalanobis distance for within node homogeneity measures and Zhang suggested a tree can analyze multiple binary responses using generalized entropy criterion which is proportional to maximum likelihood of joint distribution of multiple binary responses. In this paper, we will modify CART procedure and suggest a new tree-based method that can analyze multiple binary responses using similarity measures.

• 환경영향평가
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• 제6권1호
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• pp.67-76
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• 1997

The purpose of this research is to draw out the factors affecting the residents' evaluation on valuable animal and vegetation and the naturality of vegetation seen near regional environment. With this purpose, Questionnaire research and vegetation survey focusing on area of types of vegetation and species of big trees were made in 30 points of midstream of Tama River, Tokyo, Japan. The questionnaire research was based on basin environment units in order to be reflective of regional natural environment. The vegetation was classified into 5 types according to its flora and observed the covering area of each points and types through the aerial photograph. In addition, the species of big trees in habitat were listed by the survey. Results as below came out by analyzing the outcome of the questionnaire research and vegetation survey by multiple regression. First, residents are most likely not to distinguish precisely between the quantitative and qualitative aspects of vegetation. Both of the researches are apt to be influenced by quantitative factors of vegetation. Second, residents are assumed to consider forest of big trees, inhabitant of groups of big trees, highly natural.

• 대한공간정보학회지
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• 제18권4호
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• pp.11-20
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• 2010

도시화에 따른 이산화탄소의 발생이 증대되고 있는 실정에서 이를 해결할 수 있는 대안으로 도시의 녹지화가 추진되고 있다. 도시지역에서 수목은 이산화탄소를 저감시킬 뿐만 아니라 심미적인 효과가 있다. 본 연구에서는 이러한 수목의 공간정보를 효율적으로 추출하기 위하여 라이다 자료를 이용하는 방법론을 제안하였다. 제안한 방법론에서는 수목추출에 따른 작업의 효율성을 향상시키기 위하여 점, 면, 영상기반의 복합적 자료처리를 수행하였다. 기존의 정규화된 수치표면모델은 건물과 수목정보를 모두 포함하고 있어 수목 추출 시 자료처리의 복잡성이 높은 문제점을 안고 있다. 따라서 이러한 문제점을 개선하기 위하여 본 연구에서는 건물추정영역을 제거한 수치표면모델을 이용하였다. 제안한 방법론의 적용성을 평가하기 위하여 도시지역 내의 건물과 수목이 공존하는 3개의 지역을 선정하였으며 수목추출의 정확도는 디지털 카메라에 의해 촬영된 디지털 영상과 비교하였다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 1998년도 추계종합학술대회
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• pp.141-145
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• 1998

This paper CMOS full adder design method based on carry-propagation-free addition trees and a circuit technique, so called multiple-valued current-mode (MVCM) circuits. The carry-paopagation-free addition method uses a redundant digit sets called redundant positive-digit number representations. The carry-propagation-free addition is by three steps, and the adder can be designed directly and efficiently from the algorithm using MVCM circuit. We demonstrate the effectiveness of the proposed method through simulation(SPICE).

• 한국통신학회논문지
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• 제34권12B호
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• pp.1336-1348
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• 2009

본 논문에서는 무선 애드 혹 네트워크에서 비디오 스트리밍 세션을 위한 무선 단말의 에너지를 고려한 다중 트리 멀티캐스트 기법인 MVM-MAODV를 제안한다. 기존의 단일 트리 멀티캐스트 기법인 MAODV를 기반으로 하여 무선 단말의 잔여 에너지와 사용자의 요구에 따라 차등화된 품질의 비디오를 전달하는 다중 멀티캐스트 트리를 구성한다. 데이터 송신자는 MDC (Multiple Description Coding)로 비디오 데이터를 인코딩하여 두 개 이상의 서브 스트림을 생성한다. 각 멤버 단말은 예상되는 스트림별 패킷 수에 근거하여 자신의 잔여 에너지로 수신 할 수 있는 서브 스트림의 개수를 결정한다. 중간 전달자 역할을 담당하는 무선 단말들도 자신의 잔여 에너지를 고려하여 전송을 지원할 수 있는 서브 스트림을 선택한다. 결과적으로 서브 스트림 별로 멀티캐스트 트리가 구성되게 되고, 데이터 송신자는 이 트리들을 사용해서 서브 스트림들을 분리하여 전송한다. 각 멤버 단말은 참여한 트리의 개수에 따라 다른 품질의 비디오를 수신하게 된다. 시뮬레이션을 통한 성능 분석에서, 단일 멀티캐스트 기법인 MAODV, 기존의 다중 멀티캐스트 트리 기법인 MT-MAODV에 비해 보다 우수한 비디오 품질을 제공할 수 있으며 네트워크 내의 무선 단말들의 에너지를 보존할 수 있음을 보였다.

• 한국조경학회지
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• 제33권5호통권112호
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• pp.57-68
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• 2005

This study surveyed planting areas along streets in Gangwon-do to find out how to improve the planting and use of street trees and herbaceous plants. There were 301,491 trees of 41 species on the streets of Gangwon-do in 2004. The predominant species of street trees were Ginkgo biloba ($40\%$), Prunus spp. (Prunus yedoensis and Prunus sargentii) ($25\%$), Platanus occidentalis ($5\%$), followed by Betula platyphylla var. japonica, Zelkova serrata, Prunus armeniaca var. ansu, Acer palmatum, and Pinus thunbergii. Eighty-four herbaceous plant species were found in the Youngseo district (the southern area of Gangwon-do); the ratio of native species to exotic was 51:33. The predominant species were Cosmos bipinnatus, Petunia hybrida, Tagetes spp., Aster koraiensis, and Fagopyrum esculentum. Eighty-nine herbaceous plant species were found in the Youngdong district (the eastern area of Gangwon-do); the ratio of native species to exotic was 55:33. The predominant herbaceous plants were Aster koraiensis, Tagetes spp., Petunia hybrida, Rudbeckia bicolor, Cosmos bipinnatus, Salvia splendens, Brassica oleraceae var. acephala, Aquilegia buergeriana var. oxysepala, Coreopsis drummondii, Viola tricolor, and Dianthus superbus var. longicalycinus. Appropriate pruning adds to the aesthetic value of trees and prolongs their useful life; it also maintains good health and thereby reduces the need to control insects and diseases. Street trees had not been properly pruned due to the presence of power lines and a shortage of pruning information. The pruning was controlled by Korea Electric Power Company, which has no pruning information. Pruning must be maintained by a professional landscape company in order to maintain good shape, such as that which is done for bonsai. In order to improve the planting, use and maintenance of landscape plants in Gangwon-do, the following recommendations are made: street tree species should be diversified, suitable street trees should be selected for each space, native species should generally be used, trees should be appropriately pruned and properly fertilized, pests and diseases should be controlled, plantings should be done in multiple layers, spatial arrangements should be improved, larger trees should be planted, and drainage and underground electric wires should be considered when planting.

• Journal of Ecology and Environment
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• 제43권4호
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• pp.364-375
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• 2019

Background: Ecologists continue to investigate the factors that potentially affect the pattern and magnitude of tree damage during catastrophic windstorms in forests. However, there still is a paucity of research on which trees are more vulnerable to direct damage by winds rather than being knocked down by the fall of another tree. We evaluated this question in a mixed hardwood-softwood forest within the Big Thicket National Preserve (BTNP) of southeast Texas, USA, which was substantially impacted by Hurricane Rita in September 2005. Results: We showed that multiple factors, including tree height, shade-tolerance, height-to-diameter ratio, and neighborhood density (i.e., pre-Rita stem distribution) significantly explained the susceptibility of trees to direct storm damage. We also found that no single factor had pervasive importance over the others and, instead, that all factors were tightly intertwined in a complex way, such that they often complemented each other, and that they contributed simultaneously to the overall susceptibility to and patterns of windstorm damage in the BTNP. Conclusions: Directly damaged trees greatly influence the forest by causing secondary damage to other trees. We propose that directly and indirectly damaged (or susceptible) trees should be considered separately when assessing or predicting the impact of windstorms on a forest ecosystem; to better predict the pathways of community structure reorganization and guide forest management and conservation practices. Forest managers are recommended to adopt a holistic view that considers and combines various components of the forest ecosystem when establishing strategies for mitigating the impact of catastrophic winds.

• Journal of Information Technology Applications and Management
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• 제14권3호
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• pp.137-149
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• 2007

Most of hospitals, especially small-scale hospitals, have tried to get customers through the Internet as what companies have done recently. There are various attempts that increase visits to one's web-site in plastic surgery hospitals. However, in plastic surgery, there have been few studies on which an attribute contributes to increase the number of web-site visit. In order to derive the important attributes on the number of visit, we compared functional attributes of 30 high-visit plastic surgery web-sites with those of 30 low-visit web-sites using statistical and data mining methods. For analysis, three methods have conducted including Multiple Discriminant Analysis (statistical method), Decision Trees (data mining method), and Artificial Neural Network (data mining method). Furthermore, results of each method have been evaluated one another. The result of this study shows that a few attributes like 'Simulating cyber plastic surgery program', 'recommendation of information' explain the number of the visitors between high and low visit web-site. The methodology employed in this study provides an efficient way of improving satisfaction of visitors of plastic surgery website.