• Title/Summary/Keyword: ferns

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Habitat Suitability Modeling of Endangered Cyathea spinulosa (Wall. ex Hook.) in Central Nepal

  • Padam Bahadur Budha;Kumod Lekhak;Subin Kalu;Ichchha Thapa
    • Journal of Forest and Environmental Science
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    • v.39 no.2
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    • pp.65-72
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    • 2023
  • The endangered species of Cyathea spinulosa (tree ferns) are among the least concerned ferns of Nepal that bring threats to them and their habitat. A way to reduce such threats is by maintaining a database of species' whereabouts and generating a scientific understanding the habitat preferences. This will eventually help in the formulation of conservation plans for the species. This research aimed to characterize the suitable habitat of C. spinulosa by enumerating the location of species in the Panchase Forests of central Nepal. The statistical index method was applied to relate the occurrence locations of species with various environmental factors for the development of indices. The suitable habitat of C. spinulosa (more and most suitable categories) covered 119 km2 and accounted for 43% of the total area studied. 74.4% of occurrence locations of C. spinulosa were recorded from these habitats. The habitat characteristics suitable for C. spinulosa were: proximity to streams (high moisture), land covered by forested area (shady area), mid-elevations of hills about 1,000 m to 2,000 m (sub-tropical climate), slope gradient of 20° to 40° (steep slopes), and northern to eastern aspects. These habitat characteristics could be considered for in-situ protection of tree ferns and designating the conservation plots.

The Construction of EUROFIX system into the Korean Loran-C Chain(9930) (Loran-C 한국체인(9930)에의 EUROFIX 시스템 구축)

  • 김민정;김경태
    • Journal of the Korean Institute of Navigation
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    • v.25 no.4
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    • pp.335-345
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    • 2001
  • While recognizing that Loran-C is very important as a back-up for satellite systems, the introduction of EUROFIX, that it uses Loran-C system, was proposed and admitted at 9th FERNS(Far East Radio Navigation System) Meeting. But, the FERNS countries should consider whether the cost-effectiveness of the system could be improved by making use of its communication facilities to integrate more closely with satellite systems. And, the members were requested to give this proposal consideration before the l0th session of the Council. or this matter, Korea planned to demonstrate transmitting EUROFIX signals from Pohang Loran-C station (Master of 9930 Chain) during the l0th FERNS Meetings. Therefore, this thesis describes the analysis of EUROFIX datalink and progress of EUROFIX construction work. This thesis is the report with regard to the sequence of this demonstration of EUROFIX in Korea.

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Enumeration of edible and useful ferns (Pteridophytes) in the Bhutan Himalayas

  • Rinchen DORJI;Choki GYELTSHEN;PHUENTSHO PHUENTSHO;Karma Ugyen WANGMO;Kencho DORJI
    • Korean Journal of Plant Taxonomy
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    • v.52 no.4
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    • pp.235-245
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    • 2022
  • Bhutan is endowed with rich biodiversity with several edible and useful fern species. Ferns have been used by local communities for centuries as vegetables, ethnobotanical artifacts, and as medicines. Owing to the limited study of edible and useful pteridophytes in the country, the knowledgebase remains poor. In this study, we attempt to document edible and useful fern species in the country scientifically while also providing an annotated checklist.

The Distribution and Life-form of Ferns in Gwangneung Forest (광릉숲 양치식물의 분포와 생활형)

  • Lee, Kang-Hyup;Yeo, Kyung-Taek;Jung, Seung-Sun
    • Korean Journal of Plant Resources
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    • v.19 no.5
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    • pp.592-597
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    • 2006
  • To understand the status of ferns' distribution of Gwangneung forest, flora survey was done during the period of April 2003 to November 2005. The results obtained from this study were as follows: Ferns identified and surveyed were 46 taxa including 9 families 17 genera 43 species 3 varieties were recorded in Gwangneung Forest. Hemicryrtophyte (H) was the most common dormancy from recorded in surveyed area. Epiphyte (E) and Hydatophyte (HH) were calculated as 4.3%, 2.2%, respectively and they were the lower value compared to those of other dormancy form. Consequently, $H-R_{3}-D_{1}-t$ was recorded as the most common life-form of ferns in Gwangneung Forest. Pteridophyta-Quotient (Ptph.-Q.) was calculated as 1.28 and it was the higher value compared to those of other neighboring mountains.

Design and Implementation of Video Search System robust to Brightness and Rotation Changes Based on Ferns Algorithm (Ferns 알고리즘 기반 밝기 및 회전 변화에 강인한 영상검색 시스템 설계 및 구현)

  • Yoon, Seok-Hwan;Shim, Jae-Sung;Park, Seok-Cheon
    • Journal of Korea Multimedia Society
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    • v.19 no.9
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    • pp.1679-1689
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    • 2016
  • Recently, due to the rapid development of multimedia technologies, as image data has been extensive and large-scaled, the problem of increasing the time needed to retrieve the desired image is gradually critical. Image retrieval system that allows users to quickly and accurately search for the desired image information has been researched for a long time. However, in the case of content-based image retrieval representative Color Histogram, Color Coherence Vectors (CCV), Scale Invariant Feature Transform (SIFT) used in sensitive to changes in brightness, rotation, there is a problem that can occur misrecognized division off the power. In this paper, in order to evaluate the video retrieval system proposed, no change in brightness, respectively 0°, 90°, 180°, 270° rotated brightness up based on the case of changing, when the brightness down the results were compared with the performance evaluation of the system is an average of about 2% to provide the difference in performance due to changes in brightness, color histogram is an average of about 12.5%, CCV is an average of about 12.25%, it appeared in the SIFT is an average of about 8.5%, Thus, the proposed system of the variation width of the smallest in average about 2%, was confirmed to be robust to changes in the brightness and rotation than the existing systems.

Synthetic Seed Development and Production for Industrialization of Eastern Bracken (고사리 산업화를 위한 인공종자 개발 및 생산)

  • Bo Kook Jang;Ju Sung Cho;Cheol Hee Lee
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2021.04a
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    • pp.11-11
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    • 2021
  • Ferns have been consumed as food in many countries for centuries. As rich sources of protein, fiber, minerals, vitamins, essential amino acids, and fatty acids, ferns provide important nutrients to humans. Eastern bracken (Pteridium aquilinum var. latiusculum (Desv.) Underw. ex A. Heller) is the most popular edible fern in South Korea where, additionally, it has long been used as an edible wild leaf vegetable. Recently, the production of eastern brackens in South Korea (2018) has reached 14,032 tons, for an annual revenue of 83.5 billion won, and even more eastern brackens are marketed if imports are taken into account as well. Most of the common ferns can be propagated using spores. However, fern farmers cultivate seedlings through traditional propagation methods, such as root pruning or rhizome division. These propagation methods exhibit limitations in forming roots and growing-points and are labor intensive. Quality seedlings of eastern bracken can be obtained through spore propagation, but the spores are fine and difficult to handle in the field. In addition, it would require appropriate environmental control. The production of synthetic seeds using encapsulation technology is easy to establish and it can be used to achieve high productivity at low cost. Synthetic seeds contain explants embedded into a seed foam, and they overcome the limitations of micropropagation and offer the possibility of using plug seedlings. Synthetic seed matrix, such as sodium alginate, has the advantages of low cost, low toxicity, and gel stability. The present study aimed to develop and produce synthetic seeds for the commercial exploitation of eastern bracken. Furthermore, we verified spore germination and the extent of gametophyte and sporophyte development achieved with our new synthetic seeds, whose production was intended to solve current problems with the handling, storage, and transportation of eastern bracken.

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