• Animal Systematics, Evolution and Diversity
• /
• v.19 no.1
• /
• pp.139-147
• /
• 2003

Burckhardt (1987) combined Aphalaridae and Spondyliaspididae into the Psyllidae, as there were no character sets which had clearly defined these three families. During the analysis on the character evolution of the psyllids from the world including Australia, there were a few different results for the taxonomy of the Spondyliaspidinae. 52 species and 28 genera in the Australian native psyllids were dissected to examine the taxonomic position of the subfamily Spondyliaspidinae. All of the dissected psyllids in the subfamily Spondyliaspidinae had one follicle in the male testes, but the subfamilies of the Psyllidae except Spondyliaspidinae were having two or more follicles. By the characteristics with living on the Eucalyptus host plants recently evolved, having just one follicle which clearly defined it from other families and experienced an explosive specific diversification in the Gondwana region, it is reasonable to separate the subfamily Spondyliaspidinae from the family Psyllidae with two or more follicles.

• Proceedings of the Korean Information Science Society Conference
• /
• 2003.10a
• /
• pp.178-180
• /
• 2003

최소 걸침 나무는 널리 알려진 순회 판매원 문제와 같이 전통적인 최적화 문제 중에 하나이다. 특히나 최소 걸침 나무와는 달리 차수 제약 최소 걸침 나무의 경우는 일반적으로 NP-hard 문제로 알려져 있다. 이러한 NP-hard 문제를 해결하기 위한 다양한 접근법들이 소개되었는데 유전 알고리즘은 효율적인 방법 중에 하나로 알려져 있다. 유전 알고리즘과 같이 진화에 기반을 둔 알고리즘을 어떤 문제에 적응하기 위해서 가장 우선적으로 고려되어야 하는 것은 해를 어떻게 표현할 것인가 인데 본 논문에서는 차수 제약 최소 걸침 나무를 해결하기 위한 새로운 트리 표현법을 제안한다.

• Journal of KIISE:Software and Applications
• /
• v.32 no.4
• /
• pp.268-276
• /
• 2005

This paper deals with optimum communication spanning tree(OCST) problem. Generally, OCST problem is known as NP-hard problem and recently, it is reveled as MAX SNP hard by Papadimitriou and Yannakakis. Nevertheless, many researchers have used polynomial approximation algorithm for solving this problem. This paper uses evolutionary algorithm. Especially, when an evolutionary algorithm is applied to tree network problem such as the OCST problem, representation and genetic operator should be considered simultaneously because they affect greatly the performance of algorithm. So, we introduce a new representation method to improve the weakness of previous representation which is proposed for solving the degree constrained minimum spanning tree problem. And we also propose a new decoding method to generate a reliable tree using the proposed representation. And then, for finding a suitable genetic operator which works well on the proposed representation, we tested three kinds of genetic operators using the information of network or the genetic information of parents. Consequently, we could confirm that the proposed method gives better results than the previous methods.

• The Science & Technology
• /
• s.526
• /
• pp.74-75
• /
• 2013

• Proceedings of the Korean Society of Environment and Ecology Conference
• /
• 2011.04a
• /
• pp.31-33
• /
• 2011

화외밀선(EFN)의 형태로 엽연부의 엽맥 끝에 넥타를 분비하는 것은 가막살나무 5 수종에서 모두 관찰되었다. 가막살나무, 산가막살나무에서는 잎 뒷면 선점(pellucid dot)이 분포하는 것이 좋은 방어전략이라 판단된다. 가막살나무의 선점에서 넥타를 먹는 포식응애들이 다수 관찰되었다. 분꽃나무의 잎 뒷면에는 성모 이외에 별모양의 부드러운 털이 있으며, 이를 포식응애가 먹는 것이 관찰되었으며, 이 구조가 가막살나무, 산가막살나무에서의 선점과 같은 역할일 것이라 추정되나 좀더 정밀한 연구가 필요할 것이라 판단된다. 수종별로 독특한 방법으로 초식에 대한 방어전략을 개발하면서 꾸준히 진화하고 있다고 판단된다. 여기에 화학적 방어전략이 추가된다면 식물이 살아남기 위하여 얼마나 열심히 노력하고 있는가를 어느 정도 이해할 수 있을 것이라 기대된다.

• Proceedings of the Korean Information Science Society Conference
• /
• 2003.10b
• /
• pp.823-825
• /
• 2003

시간이 흐름에 따라 생화학 시스템이 변화하는 것을 기록한 데이터로부터 이 시스템의 상태 전이 및 시스템을 구성하는 각 생화학 물질간의 관계를 모델링하기 위한 방법으로 S-tree 구조를 제안한다. 이것은 주로 생화학 시스템의 동적 특성을 모델링 하기 위하여 연구되어 온 S-system을 나무 구조로 표현한 것이다. 본 논문에서는 진화 연산을 통해 주어진 시계열 데이터를 잘 설명하는 S-tree의 구조 및 그 변수들을 동시에 효과적으로 탐색하는 방법을 개발하였다. 이 방법에서는 구조 탐색을 위해 유전 프로그래밍(genetic programming)에서 사용되어 온 나무 구조의 교차 및 돌연변이 연산과 더불어 다양한 형태의 구조 탐색 연산자들을 도입하였고, 또한 동시에 알맞은 변수 값들을 찾기 위하여 확률적 돌연변이 연산을 통한 언덕 오르기(hill-climbing)를 수행한다. 제안된 방법을 효모의 혐기성 발효 데이터에 적용한 결과 주어진 시스템을 성공적으로 모델링할 수 있었다.

• Korean Journal of Plant Taxonomy
• /
• v.44 no.3
• /
• pp.202-207
• /
• 2014

Lonicera insularis Nakai (Caprifoliaceae) is Korean endemic plant that lives along the shore of Ulleungdo and Dokdo. The aim of this study is to construct a phylogenetic relationship within six species (L.maackii, L.chrysantha, L.subsessilis, L. harai, L. morrowii) of genus Lonicera L. and Wigela subsessilis as outgroup and intraspecific variation of L. insularis using chloroplast DNA five regions sequences. Sequence analysis revealed that both L. insularis and L. morrowii showed complete homologies in the intergenic regions of trnL-trnF, trnS-trnG, psbM-trnD and matK coding region. However, sequence in the petN-psbM intergenic region showed a single nucleotide difference between both species, thus we designated them as CP01 and CP02. The plants having CP01 are prevalent in the Ulleungdo and Dokdo, while L. insularis and L. morrowii from Ulleungdo and of Dokdo, and Japan have CP02. This confirmed the existence of two cp DNA lineages with different geographical distributions. We can infer the allopatric speciation by geographical barrier. The result will provide the important basal data to study speciation and specie evolution of ocean islands such as Ulleungdo and Dokdo.

• Journal of Korean Society of Forest Science
• /
• v.67 no.1
• /
• pp.1-9
• /
• 1984

Taxonomical studies of the genus Acer in Korea (8 species, 3 varieties and 1 forma) were studied by the morphological characteristics of stipules. The results obtained were summarized as follows; 1) The stipules of the genus Acer were arranged oppositely with 4 - 10 stipules consisting of simple leaf, compound leaf and unifoliate compound leaf. The venation of stipules were cladodromous, basal reticulate, fibrous and palmately netted vein. The trichoma of stipules were glandula hair, glandular pubescent, sericeous, pilous, vinous, velutinous, tomentose, ciliate and lanate. As the morphological characteristics of stipules in the genus Acer established a strong point in the identification of species. 2) The species in the genus Acer in Korea were classified into six groups; (1) ginnala group (A. ginnala), (2) koreanum group (A. koreanum, A. japonicum, A. pseudosieboldianum var. koreanum), (3) mono group (A. mono, A, palmatum var. sanguineum, A. palamtum var. dissectum, A. palmatum var. dissectum f. aosidare), (4) negundo group (A. negundo), (5) palmatum group (A. palmatum), (6) platanoides group (A. platanoides, A. truncatum) by the morphological characteristics of stipules, 3) The stipules of platanoides group and negundo group were the least evolved types among the species in the genus Acer. 4) The stipules in the genus Acer were made the inner buds that were metamorphosed to the protected functional aspect by the evolution of petiols.

• Journal of Korean Society of Forest Science
• /
• v.82 no.3
• /
• pp.260-270
• /
• 1993

This study was carried out to clarifyed a taxonomical relationships of Rutaceae on the subfamily, genus and species level in Korea using venation pattern and stomata types. The results are summarized as follows : The leaf venation of the Rutaceae has revealed three major venation types. Semicraspedodromous, Brochidodromous and Cladodromous. The leaf ufmations type of the genus Evodia and Phellodendron were similar to Cladodromous type. They showed gradual evolution from brochidodromous type of Aurantioideae to cladodromous type of Toddaloideae. The stomata ypes were reconized Anomocytic and Actinocytic type, and epidermal cells were Ansio. Polygonal and Medium type. In the correlation analysis, there were highly significant correlation between frequency and length (r=-0.822), frequency and width (r=-0.780), and length and width(r=0.909) at 1% level.

• Korean Journal of Environment and Ecology
• /
• v.34 no.5
• /
• pp.358-371
• /
• 2020

As climate change is expected to lead to a severe reduction of biodiversity, studies to investigate the reasons for habitat loss, growth decline, and death of Korean fir (Abies koreana Wilson), endangered alpine/subalpine species in Korea, have been conducted for years but found no clear answer yet. This study reviewed previous studies on Korean fir published in the journals in the past 40 years, 1980 through 2020, into 10-year units, examined the study trend by period, region, and subject with a focus on ecological studies, and analyzed the study results. The ecological studies were categorized into evolutionary ecology, physiological ecology, population ecology, and landscape ecology. Based on the results, we suggested the required research fields in the future. We found a total of 73 papers published in the past 40 years and 48 (65.8%) of them published in the past 10 years. In terms of region, Mt. Halla accounted for the most as 41 papers were on it. In terms of ecological subjects, the physiological ecology accounted for the most with 38, and the evolutionary ecology accounted for the least with 10. The review of the study results showed that many studies identified water stress caused by the water resource imbalance due to temperature increase and spring precipitation reduction following climate change as the main reason for the decline and habitat loss of Korean fir. However, recent studies suggested other factors, such as soil environment, disturbing organisms, and climatic events. The cause of the decline and death of the Korean fir not yet being clearly identified is that most of the studies dealt with the basic content, were carried out intermittently, and were concentrated in some regions. Therefore, we need long-term studies with advanced technology in each study subject at a local scale to find the cause of Korean fir decline and present sustainable management and conservation. Moreover, it is necessary to extend our study subjects to ecosystem ecology and systems ecology to integrate the results from various study subjects for a comprehensive understanding of the reason for Korean fir declines. The results of comprehensive studies could provide clearer answers for Korean fir's declines and the alternatives of conservation management and practices.