• The Korean Journal of Zoology
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• v.8 no.2
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• pp.89-127
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• 1965

1. This report is on the outcome of observation made up the breeding process of Narcissus flycatcher, Muscicapa narcissina zanthopygia, using 15 ness-boxes at Seoul and Kwang Nung Experimental forest in 1964, and the relevant feeding habit was studied by the collar method of wrapping the necks of thenestlings for 50-60 minutes or more in some cases from 1963 to 1964. 2. The Narcissus flycatcheris a common summer resident throughout Korea arriving at the end of April. The earliest data of arrival of this species in Seoul, is April 26, 1964. They migrate southward from the later part of September to early part of October. 3. In a week after their arrival , they start to build nest after a brief courtship. Male and female prepare their nest ina nestboxes in 4 or 5 days. Nests are usually found in the moss, which provide definite frame-work. The inner side of the nest is usually composed of roots of Gramineae or leaves of pine, oak or other broad leave tree. 4. The laying period is generally from the later part of April to the middle of June : and the number of eggs laid is from 3 to 8 , therefore 5 in average : eggs are pink with traces of milky yellow blending of light auburn and orange red spots and chicken-egg-like in shape. 5.The incubation takes place for 7-12 days from the middle part of May to the middle of June, in the order of male and female . The hatching rate tends to increase in proportion to clutch size. 6. The feeding period usually lasts 15 days in average from the early part of June to the middle of July and the feeding urge tends to increase in proportion to brood size. 7. The animals invading into their nest-boxes are red ants, chipmunks, bees , barkbeetles and philippine red-tailed shirkes, etc. 8. On the basis of analysis covering 714 birds in 31 nests, the food they consumed during the nesting period of nestlings were mostly of animal matters composing of : insect larvae form-39. 88% insect adult form 36.26%, insect pupae-0.19%, spider-17.75% and other animal matters 5.92% , Besides a small amount of plant pieces were found . As to the insect larvae, Lepidoptera was the largest in the content followed by Hymenoptera , Orthoptera and Coleoptera. As to the insect adult, Diptera was the largest in the content followed by Coleoptera, and Hymenoptera. In view of forest protection, noxious insect was of 69.38%, useful insect 4.39%, and spider 17.75%. 9. The rich assortment of its food, the ability of acquiring various insect (adults as well as larvae), its destruction of great numbers of harmful insects , and its quick assimilation artificial nesting with the nest-boxes of 2.5-3cm entrance hole employed, allow us to conclude that the flycatcher may be successfully employed in the elimination of fores pests. The above results are only that part obtained near Seoul in the middle of Korea, however, if we would extend the scheme to other broad areas using similar techniques, the nest-boxes could not only be well used by the birds, but also it would help to prevent the increase of harmful. insects.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.787-790
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• 2015

Recently, M2M (Machine to Machine) communication is possible the development of MTC (Machine Type Communication) devices becomes active. MCT devices in the form of home appliances have a low power consumption, low cost, short-range wireless communication in wireless home network. For purpose, MTC devices based on IEEE 802.15.4/Zigbee are composed in the form of cluster-tree topology, which consists of one PAN (Personal Area Network), one or other router and end of nodes. It happens that transmission delay, packet drop, and lacking data resulted from collision originated by a competition for allocating channels among MTC devices that greatly increased. At last performance of entire network can be degradated. This paper proposes that the beacon frame-based grouping algorithm using multiple channels in a MTC devices in the presence of wireless home network interference. The proposed algorithm decreases the transmission delay, dropped packet and throughput is more increase, so the proposal algorithm is more efficient than the IEEE 802.15.4/ Zigbee standard.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.39 no.3
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• pp.15-21
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• 2021

This study studied the value of the spatial organization of the temple and the form of the garden located in the Seojang area in the southwestern regions of China. The value of the Lama temple was looked into by examining the relationship between Lamaism and Lama temple through the spatial organiz ation, building arrangement, and garden of temples that served as the center of history, culture, and politics of the time in the process of converging Buddhism introduced through China's central districts and India with folk beliefs in Seojang through the poor environment. To this end, the value of the space and garden of the Lama temple was derived through the representative Lama temples, Potala Temple, Norbulingka Temple, and Dazhao Temple. First, due to the unique environment in which ice caps and green areas coexist, the representative Lama temples in Seojang, Potala Temple, Norbulingka Temple, and Dazhao Temple, are widely distributed in the form of leaning against valleys and mountain ranges based on folk beliefs and Buddhism's Jatabuli(自他不二) and mandala. the target sites are largely divided into upper and lower spaces. Second, the target sites are largely divided into upper and lower spaces. Buildings for worship are located in the upper space, and spaces for practice and garden are located in the lower space. The garden existed in two main forms. Third, the garden existed in two main forms. Located in the center of the practice space, the garden had an ideal structure to plant bo tree to escape from the two false obsession and go to a world of truth that is with the Buddha behind the world through practice like Sakyamuni, and there was a garden around the temple where meditation and exchange took place. Evergreen coniferous forests are mainly planted in the forests.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.40 no.3
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• pp.67-73
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• 2022

This study tracked the changing process of unregistered private house gardens by using the form at the time of the construction of gardens as the prototype of each garden, investigated the spatial value of the garden, and discussed the historical spatial value of unregistered private house gardens in terms of inheritance and change of traditional gardens. To this end, targeting on unregistered private house gardens in Gangwon-do, which are in danger of preserving their gardens due to the recent increase in the number of designated cultural heritage dismantled, the patterns of unregistered private house gardens, their characteristics and values were identified through the spatial change of the garden, and the following results were derived. First, the unregistered private house gardens were able to inherit and maintain the form of a traditional garden, being located in a clan village. The garden space was divided by the influence of Confucian philosophy, and the components of the garden, tree species and planting methods appeared differently. In other words, the use of garden components according to the status hierarchy appeared. Second, space reduction was continuously confirmed at four target sites. The reduced spaces are garden spaces, and part of the garden was attributed to the state due to the building of new road and environmental improvement project. The reduced spaces are garden spaces, and part of the garden was attributed to the state due to the new road and environmental improvement project. Third, eight old big trees over 100 years old were identified in three of the four target sites, and the garden components such as stone water tanks, quickset doors, and ponds were commonly identified in Korea, China, and Japan during the Joseon Dynasty, inheriting the historicity of the traditional garden.

• Journal of Korean Society of Forest Science
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• v.14 no.1
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• pp.39-44
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• 1972

Cytological investigation was done on a tetraploid tree of Robinia pseudoacacia L. selected in the planted forest in Chilbo Mountain. From the results of observation of chromosomes on mitotic metaphase in leaves, it was confirmed that the mutant is tetraploid plant (2n=40). The external form of leaves of the spontaneous tetraploid was gigantic and dark green one in comparison with diploid. There was no difference in the size of guard cell and the number of stomata per unit area between the mutant and the diploid plant, however, length and thickness of wood fiber were increased as compared with that of diploid. The spontaneous gigas tetraploid showed growth performance as much as the colchicine induced gigas tetraploid.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.48 no.2
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• pp.6-13
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• 2011

This paper deals with the interconnection problem in ad-hoc networks or sensor networks, where relay nodes are deployed additionally to form connections between given nodes. This problem can be reduced to a NP-hard problem. The nodes of the networks, by applications or geographic factors, can be deployed densely in some areas while sparsely in others. For such a case one can make an approximation scheme, which gives shorter execution time, for the additional node deployments by ignoring the interconnections inside the dense area of nodes. However, the case is still a NP-hard, so it is proper to establish a polynomial time approximation scheme (PTAS) by implementing a dynamic programming. The analysis can be made possible by an elaboration on making the definition of the objective function. The objective function should be defined to be able to deal with the requirement incurred by the substitution of the dense area with its abstraction.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.6
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• pp.2492-2512
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• 2018

Multicast communication can effectively reduce network resources consumption in contrast with unicast. With the advent of SDN, current researches on multicast traffic are mainly conducted in the SDN scenario, thus to mitigate the problems of IP multicast such as the unavoidable difficulty in traffic engineering and high security risk. However, migration to SDN cannot be achieved in one step, hybrid SDN emerges as a transitional networking form for ISP network. In hybrid SDN, for acquiring similar TE and security performance as in SDN multicast, we redirect every multicast traffic to an appropriate SDN node before reaching the destinations of the multicast group, thus to build up a core-based multicast tree substantially which is first introduced in CBT. Based on the core SDN node, it is possible to realize dynamic control over the routing paths to benefit traffic engineering (TE), while multicast traffic manageability can also be obtained, e.g., access control and middlebox-supported network services. On top of that, multiple core-based multicast trees are constructed for each multicast group by fully taking advantage of the routing flexibility of SDN nodes, in order to further enhance the TE performance. The multicast routing and splitting (MRS) algorithm is proposed whereby we jointly and efficiently determine an appropriate core SDN node for each group, as well as optimizing the traffic splitting fractions for the corresponding multiple core-based trees to minimize the maximum link utilization. We conduct simulations with different SDN deployment rate in real network topologies. The results indicate that, when 40% of the SDN switches are deployed in HSDN as well as calculating 2 trees for each group, HSDN multicast adopting MRS algorithm can obtain a comparable TE performance to SDN multicast.

• Korean Journal of Plant Resources
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• v.21 no.1
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• pp.12-18
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• 2008

Antioxidative activity and inhibitory activity of angiotensin I converting enzyme(ACE), aminopeptidase N(APN) and $\alpha$-amylase were investigated in the methanol extracts from 25 fern plants native to Jeju Island, in order to screen the plant species containing bioactive materials for functional foods or medicines. The antioxidative activity was higher in Cytomium fortunei(41.9%) and Rumohra standishii(34.1%) than in leaves of Thea sinensis(30.9%), a small tree for antioxidative beverage. Inhibitory activities of ACE and APN were relatively high in Cytomium fortunei as 26.7% and 28.2% respectively. $\alpha$-Amylase inhibitory activity was higher than 50% in 10 species. Particularly, Cytomium fortunei(87.4%) and Dryopteris erythrosora(71.6%) showed the inhibitory activities higher than those of other form plants. Of 25 fern plants investigated here, Cytomium fortunei showed not only the highest antioxidative activity but also the highest inhibitory activity of ACE, APN and $\alpha$-amylase. It suggests that Cytomium fortunei could be potentially used as a resource of bioactive materials for fuctional foods or medicines.

• Journal of Korean Elementary Science Education
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• v.26 no.1
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• pp.41-48
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• 2007

The purpose of this study is to examine how many plant names elementary school children how, and what kind of criteria they use for classifying these plants. The sample involved 926 students from the 2nd, the 4th, and the 6th grades dwelling in one urban, three suburban, and six rural areas. Their level of perception on the name of plants increased in correlation to the elevation of the grade level. However, different patterns of increases were shown depending on the local environments in which they live. The most well-known plant names for students were the rose of Sharon, the rose and the pine tree. The students mostly classified the plants using the following criteria such as 'with or without flower' and 'edible or inedible' regardless as to whether they had prior loaming experience of plant classification. 65.3% of the 6th graders correctly grouped 5 kinds of plants into the flowering and the non-flowering plant categories at the 1st level of classification. However, only 17.9% and 7.7% correctly divided the flowering and the non-flowering plants into two subgroups at the 2nd level of classification respectively. Therefore, their abilities in plant classification was shown overall to be poor. The students living in suburban areas appeared to be harmonized with both the natural and urbanized surroundings and classified the plants more scientifically than those from the urban or rural areas were able to. This suggests that the conception of plant classification by children is affected by the environment in which they live. If children have more opportunities to observe plants in surroundings such as their classrooms and school gardens, it will help them to form the relevant scientific concepts as well as to correct any alternative conceptions related to classification.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.2
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• pp.143-149
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• 2000

From the soils of soybean fields in Cotton Branch Station (CBS) and Pine Tree Station (PTS), Arkansas, USA, various single spore isloates of sudden death syndrome (SDS) pathogen were obtained on modified Nash ＆ Snyder's medium (MNSM) with dilution plating technique and transferred to potato dextrose agar (PDA) medium to identify the cultural colony shape. The colony shapes of these isolates resembled F. solani isolate 171 which was white and chalky shaped on MNSM and most of them had unique form of morphology which produced white margin and blue center colony on PDA. Although, some of these isolates had more dark blue or showed slightly different color, all isolates that were selected randomly for green-house inoculation assay produced typical foliar symptoms on leaves of soybean, Hartz 6686. To determine the genetic differences among the isolates, mitochondrial DNA restriction fragment length polymorphism (RFLP) was conducted with fourty isolates from both fields, using mtDNA probes, 2U18 and 4U40, derived from Colletotrichum orbiculare. We obtained distinctive RFLPs in each treatment of restriction enzyme, EcoRI and HaeⅢ. Isolates, 11-2-5 and 14-3-1-1, from CBS and isolates, 104-3-1-2 and 701-1-5-1, from PTS showed different band patterns from 171 in both or in either treatment of restriction enzymes. Even if some of these isolates showed heterogeneous, they were more closer to 171 than PN603. And, also, rest of the thirty-six isolates had exactly same polymorphisms as 171 in each treatment of restriction enzyme. Although, some of the isolates showed the different morphological shape on PDA and slightly different band patterns on RFLPs, all of the isolates selected on MNSM due to their distinctive colony shape from other fungi produced the typical foliar symptoms on soybean leaves in greenhouse inoculation assay. It might be suggested that these isolates were not genetically different from check isolate 171 and they were unique strain of F. solani.