• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 춘계학술대회 논문집
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• pp.141-144
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• 2014

In urban spaces surrounded by buildings, trees could disperse sound energy, which affect sound level distribution and street canyon reverberation. Therefore, this paper examines the amount of scattered sound energy from a tree in open field by means of a reverberation time (RT). Five trees of different species and crown sizes were considered. The influential factors include crown size and shape, foliage condition, and source-receiver distance. The results show that RT is proportionally increased with the increase of tree crown sizes, which is the most determining factor. The maximum RT measured was 0.34 sec at 4000 Hz for the studied trees in leaf. The presence of leaves increased RT at high frequencies, typically by 0.14 sec at 4000 Hz. With increasing source-receiver distance within 40 m, RT was slightly changed.

• The Plant Pathology Journal
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• 제21권1호
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• pp.27-32
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• 2005

Leaf anthracnose was observed on leaves of Japanese spindle tree in Seoul, Korea from autumn 2003 to spring 2004. The causal fungus was purely isolated from he leaf spot lesions and cultured on PDA. The colony on PDA was cream to orange but blackish in the center n old cultures. Conidia were formed in blackish orange asses and were cylindrical in shape, measured 13-17${\times}$5-7 ${\mu}$m in size. Blackish brown setae were often observed on PDA and ranged up to 100 ${\mu}$m in length. Based on morphological and ITS region sequence analyses, the fungal strain was identified as Colletotrichum boninense. Koch’s postulates were fulfilled by inoculating tree leaves with 1 ${\times}$ $106^6$ conidia per ml in a moist chamber. This is the first study on the pathogenicity, growth and phylogenetic characteristics of C. boninense causing leaf anthracnose on Japanese spindle tree in Korea.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.247-249
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• 2007

Crown parameters are important roles in tree species identification, because the canopy is the aggregate of all the crowns. However, crown measurements with spaceborne image data have remained more difficult than on aerial photographs since trees show more structural detail at higher resolutions. This recognized problem led to the initiation of the research to determine if high resolution satellite image data could be used to identify and classify single tree species. In this paper, shape parameters derived from pixel-based crown area measurements and texture features derived from GLCM parameters in QuickBird image were tested and compared for individual tree species identification. As expected, initial studies have shown that the crown parameters and the canopy texture parameters provided a differentiating method between coniferous trees and broad-leaved trees within the compartment(less than forest stand) for single extraction from spaceborne high resolution image.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2051-2053
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• 1999

In this work, PD patterns and electrical trees are observed by use of the XLPE cable insulation. and the tree initiation voltage related to the contamination are also measured in order to calculate the electric stress necessary for the design of cable insulation. Throughout these works, correlation between the PD pattern and the shape of electrical tree has been observed that there may exist three distinct pattern of PD dependence on the stage of tree propagation, Such correlation could bring a basic information in connection with the partial discharge of cable system. It was also found that the electrical stress necessary for the initiation of electrical tree was measured to the 290kV/mm for the 154kV XLPE cables manufactured in KOREA.

• ETRI Journal
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• 제29권4호
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• pp.507-515
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• 2007

Skeleton transform of which the medial axis transform is the most popular has been proposed as a useful shape abstraction tool for the representation and modeling of human posture. This paper explains this proposition with a description of the areas in which skeletons could serve to enable the representation of shapes. We present algorithms for two-dimensional posture modeling using the developed simplified shock graph (SSG). The efficacy of SSG extracted feature vectors as shape descriptors are also evaluated using three different classifiers, namely, decision tree, multilayer perceptron, and support vector machine. The paper concludes with a discussion of the issues involved in using shock graphs to model and classify human postures.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2008년도 학술대회 1부
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• pp.618-622
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• 2008

본 논문에서는 프랙탈 이론을 이용한 새로운 자동 작곡 알고리즘을 제안한다. 사용자는 L-System에서 시작 상태 및 생성 규칙들을 설정함으로써 다양한 프랙탈 형태를 정의 및 조정할 수 있다. 본 연구에서는 먼저 L-System과 확률을 이용하여 비대칭인 프랙탈 트리를 생성한다. 그리고 생성된 프랙탈 트리의 이미지를 기반으로 음악화 기법을 이용하여 음악을 생성한다. 본 논문에서는 다음 두 가지 방법을 소개한다. 첫째로, 이미지의 x축과 y축을 음의 크기와 음정으로 매핑하여 단선율 음악을 생성한다. 둘째로, 이미지의 x축과 y축을 시간과 음정으로 매핑하여 다성음악을 생성한다. 본 논문에서 제시하는 방법을 이용하여 사용자는 프랙탈의 재귀적인 특징이 반복성으로 나타나는 음악을 생성할 수 있으며, 프랙탈 트리의 모습을 음악적 구조로 갖는 음악을 생성할 수 있다.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 동계 학술대회 논문집
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• pp.601-607
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• 2000

• 정보처리학회논문지A
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• 제9A권4호
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• pp.589-594
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• 2002

컴퓨터 그래픽에서 L-시스템은 주로 나무나 풀, 꽃 등 자연적인 모습을 생성하기 위해 사용된다. 이는 임의로 제시된 최초의 모양에 다중 축소복사 이론을 반복적으로 적용함으로써 가능하다. 본 논문은 일반적인 L-시스템 나무의 모습을 변형하여 더욱 현실적으로 묘사하는데 목적이 있다. 본 논문에서는, L-시스템에서 사용되는 단순한 반복함수를 적용하는 대신에, 반복함수를 적용하는 과정에서 나뭇가지 하나하나를 생명체로 간주하여 생명체의 속성을 부여한다. 가지의 수명, 생장속도, 모양변화, 외부환경에 따른 유인 등 생명체가 지닌 속성은 파티클 시스템을 구성하는 입자들이 지닌 기본 속성이기도 하다. 속성의 적용을 위해서 개별 속성 별로 필요한 매개변수를 바탕으로 한 가설로서의 모델을 제시하고 결과적인 다양한 나무의 모습을 제시하였다.

• 한국양봉학회지
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• 제33권4호
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• pp.227-237
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• 2018

The majority parasitic bee mites of Thailand in genus Tropilaelaps are infesting colonies of native bees (Apis dorsata) and introduced bees (A. mellifera). The investigation aims to study morphological and genetic variation of Tropilaelaps mites infected different hosts. Adult mites were collected from honey bee brood throughout Thailand. Traditional and geometrical morphometrics were measured on photograph by using TPS program. Additional, COI gene variations were examined by PCR-RFLP and nucleotides sequencing. Tree of mites relationships were constructed by NJ and MP assumptions. Morphometric results indicated T. mercedesae were major species infesting on A. dorsata and A. mellifera. Mophological variation represented at anal and epigynial plate, which the shape of the anal plate apex margin has been key character to identify between T. mercedesae (bell to blunt shape) and T. koenigerum (pear shape). However, the discriminant analysis suggested that geometric results were potential to classify Thai Tropilaelaps populations from different hosts better than traditional morphometric. Otherwise, PCR-RFLP clearly detected the site of Dra I and Xba I digestion of Thai Tropilaelaps morphotypes. The COI sequences of T. koenigerum were founded infesting only A. dorsata in Thailand and four sequences that related to the Thai T. mercedesae morphotypes. The NJ and MP tree were clearly classified Thai Tropilaelaps species which were suggested both from morphological and molecular analysis. This information might be basically of taxonomic status, but this should have implication for controlling these mites in Thailand and other countries.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -1
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• pp.462-465
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• 2002

This paper presents a basic theory of information flow from single sending point to multiple receiving points, where new theories of algebraic system called "Hybrid Vector Space" and flow vector space play important roles. Based on the theory, a new algorithm for finding maximum homogenous information flow is proposed, where homogenous information flow means the flow of the same contents of information delivered to multiple clients at a time. Effective multi-routing algorithms fur tree-shape delivery rout search are presented.