• Journal of Mushroom
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• v.22 no.1
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• pp.22-26
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• 2024

Tricholoma matsutake is a traditional favorite food in East Asia, cultivated in fairy rings called "shiro," which are found near Pinus densiflora. For effective artificial cultivation of Tri. matsutake, microorganisms from symbiotic fairy rings are co-cultivated. In this study, one bacterial isolate (Y22_B35) and two fungal isolates (Y22_F64 and Y22_F68) displayed growth-promoting effects on Tri. matsutake mycelium (158.47, 125.00, and 122.26% enhanced growth, respectively). For identification, 16S rRNA or ITS regions from the microorganisms¡¯ genomes were sequenced. Other sequences, including BenA, CaM, and RPB2 were sequenced in the fungal isolates. The bacterial isolate Y22_B35 was identified as Bacillus cereus. Y22_F64 and Y22_F68 were identified as Umbelopsis nana and Aspergillus parvulus, respectively. To identify the effects of the dominant microorganisms on Tri. Matsutake cultivation, metagenomic analyses were performed. Discovery of these Tri. matsutake mycelium growth-promoting microorganisms and metagenomics analyses are expected to contribute to our understanding of Tri. matsutake fruiting body growth and construction of biomimicry.

• Journal of Korea Foresty Energy
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• v.25 no.2
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• pp.9-15
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• 2006

The quality of wood is largely depend on the characteristics of xylem tissue and their variation. They may include tracheid length, microfibril angle, distribution and amount of resin canal, as well as specific gravity as indicator of material properties. In this study, variation of these elements between and within 30 superior families of Pinus densifloa in progeny test forest were examined and the results are as follows; In terms of elongation ratio of tracheid length which is less than 1%, the sample tree showed a transition to matured wood after 13 years particularly in Kangwon 25, 30, 90, 56 and Chungnam 4 families. The average specific gravity were from 0.35 to 0.49, and differences between the families were significant. Number of transverse resin canal per unit area were also found to be significant between the families. The microfibril angles measured at 15th ring number ranged from 0.9 degree to 28.6 degree. More studies are necessary to tell whether these variation is inherited by genetic or individual characteristic. However it would be desirable that these elements be considered as key elements in the early stage of selection process of superior tree to ensure good quality of wood production in future.

• Journal of Korean Society of Forest Science
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• v.99 no.6
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• pp.855-862
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• 2010

The objectives of this study were to analyze vegetation types and stand structures of the red pine (Pinus densiflora) in Kangwon southern region for stable and sustainable forest management. The pine forests in study sites were classified into 4 communities, 2 groups, so total 6 vegetation units. Species with high constance degree were Quercus mongolica, Rhus trichocarpa, Lindera obtusiloba, Lespedeza maximowiczii, Quercus serrata, Spodiopogon sibiricus, Aster scaber and Fraxinus sieboldiana. In the importance value(I.V.) analysis of each layer, P. densiflora showed highly in tree layer while in other layers competitive broad-leaved species such as Quercus spp. were high. P. densiflora also showed large size of DBH, while broad-leaved species distributed middle and small DBH. The annual ring growths of P. densiflora and competitive broadleaved species were variable according to area, site condition, tree year and species, it is considered that appropriate silvicultual practice methods should be employed to remove rival broad-leaved species for maintenance of sustainable red pine forests considering the characteristics of each stand.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.3 no.1
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• pp.5-25
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• 2009

In recent years the popularity of multi-hop wireless networks has been growing. Its flexible topology and abundant routing path enables many types of applications. However, the lack of a centralized controller often makes it difficult to design a reliable service in multi-hop wireless networks. While packet routing has been the center of attention for decades, recent research focuses on data discovery such as file sharing in multi-hop wireless networks. Although there are many peer-to-peer lookup (P2P-lookup) schemes for wired networks, they have inherent limitations for multi-hop wireless networks. First, a wired P2P-lookup builds a search structure on the overlay network and disregards the underlying topology. Second, the performance guarantee often relies on specific topology models such as random graphs, which do not apply to multi-hop wireless networks. Past studies on wireless P2P-lookup either combined existing solutions with known routing algorithms or proposed tree-based routing, which is prone to traffic congestion. In this paper, we present two wireless P2P-lookup schemes that strictly build a topology-dependent structure. We first propose the Ring Interval Graph Search (RIGS) that constructs a DHT only through direct connections between the nodes. We then propose the ValleyWalk, a loosely-structured scheme that requires simple local hints for query routing. Packet-level simulations showed that RIGS can find the target with near-shortest search length and ValleyWalk can find the target with near-shortest search length when there is at least 5% object replication. We also provide an analytic bound on the search length of ValleyWalk.

• Applied Microscopy
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• v.18 no.2
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• pp.153-166
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• 1988

The fine structure of the salivary glands of the pine moth, Dendrolimus spectabilis Butler, at the last larval period is observed using light and electron microscopes. The moths have single paired tubular salivary glands which openings are connected to the oral cavity through the upper jaw. By the external morphology and its functions, the glands are subdivided into three regions which are anterior reabsorptive region, middle storage region and posterior secretory region. Along the inner canal of the salivary gland two columns of the large glandular cells are connected each other and oriented to ring-like forms. By this cellular orientation, the glands have long and large tubular structure. From anterior to posterior region large nuclei of the glands are ramified like twigs of the tree, and in the cytoplasm of the cell numerous mitochondria and vacuoles are seen. Moreover, basal plasma membranes of the gland cells are heavily infolded. The anterior region of the glands keeps several characteristics related to the reabsorption of the material from the inner cavity to the glandular cells whereas, main salivary material is synthesized and secreted through the long and convoluted posterior region. The apical plasma membranes of the cells are the most heavily invaginated at the posterior regoin, but trachea and tracheoles are distributed only at the middle and posterior regions. In the cytoplasm of the middle region Golgi complexes appeared at the vicinity of the vesicles, and at the posterior region of the salivary glands multivesicular bodies are also observed.

• The Korean Journal of Quaternary Research
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• v.14 no.1
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• pp.65-71
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• 2000

The growth of Daphniphyllum macropodum at Mt. Naejang National Park(Naejang temple area) was investigated in connection with the climatic factors by the use of tree-ring analysis. A pair of cores was extracted from each of 18 trees in the D. macropodum community area near Younjabong for the analysis. The period of mater chronology based upon D. macropodum covers from 1915 to 1998. The growth rates of D. macropodum were very poor in the years 1920, 1932, 1934, 1937, 1942, 1946, 1964, 1969 and 1985, respectively. Response function was employed to understand the relationship between the growth of D. macropodum and climatic factors. The response function of the growth rates of D. macropodum indicated significant negative correlation with the precipitation of August and September. Poor growth of D. macropodum during the August and September nay be due to the frequent rain periods during the summer The heavy rain during the summer seems to decrease the solar radiation, which eventually caused the decrease of photosynthesis capacity. In conclusion, we hypothesize that the decrease of the photosynthesis rates during the rainy summer seasons may cause the slower growth of D. macropodum.

• The Korean Journal of Quaternary Research
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• v.14 no.1
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• pp.57-63
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• 2000

A simulation model was used to examine the effects of climate variation on the tree-ring structure of Larix leptolepis trees growing at a plantation plot in Worak National Park in central Korea. The model uses mathematical equations to simulate processes affecting cell(tracheid) size variations for individual rings using daily precipitation and temperature measurements. Limiting conditions are estimated from temperature, day length and a calculated water balance. The results indicate that the seasonal growth is mostly limited by the soil moisture content and precipitation income during April and May. The April-May temperature also inversely influences the growth by increasing water losses from soil. The global climate-change scenario which includes regional warming(increasing temperature in spring-summer periods) appears to decrease the duration of optimal growths. Consequently, the model estimated that Larix leptolepis would lose the total production of xylem by 25%.

• Journal of the Korea Furniture Society
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• v.25 no.4
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• pp.345-352
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• 2014

This study was carried out to develop eco-friendly wood street lamp (EFWSL) by using wood resources stacked in the forests after tree tending operations which were mostly abandoned, but economical as renewable wood resources for developing the wood coated street lamps with the effects of cost reduction and their attractive appearances. This study has led to the development of key compact structures of street-lighting wood poles (shaft) using laminated timber. The core technique in this study is related with producing the more stable wood poles (shaft) with the hole inside than wood poles exposed under the natural environment through applicable process to protect the wood from bursting and splitting. We also comprehensively developed the method to conserve the timber durability of wood shaft and connect the wood shaft with groove, race way to be located in the groove, locking ring, current stabilizer connected to the groove and luminaire support arm, base and hand-hole which was partly used in combination with steel materials and wood. Also we increased the utilization of abandoned and stacked woods after thinning in the forests such as Pinus densiflora, Larix leptolepis, and Pinus koraiensis plantations by maximizing the value of these natural wood resources as main materials of eco-friendly street lightings with the effects of cost reduction and attractive appearances and also the expectation of advertising effects of street lightings developed in this study.

• Journal of Conservation Science
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• v.8 no.1 s.11
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• pp.16-22
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• 1999

Species of 741 charcoal samples, which were excavated from the dwelling sites of the bronze age $(about\;2500\~3100\;B.P)$ at Hyeonwha-ri, Pyungteak, Korea, were identified. Most of samples were deciduous oaks (Quercus spp.; $97.7\%$) and others were alders (Ainus spp.; $1.9\%$) and soft pines (Pinus spp.; $0.4\%$). Tree rings of nine largest samples were also examined. The numbers of annual rings were 8 to 36 and mean ring width was rather narrow $(0.65\~1.82\;mm)$. Most samples possessed pith and tylosis. The results indicate that logs 10 to IS cm diameter had been used for the poles of houses without further processing.

• Journal of Conservation Science
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• v.35 no.6
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• pp.670-680
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• 2019

This study attempts to identify whether there were preferred wood species or any required properties depending on the use of wooden objects by comparing wood species analysis results of wooden objects, which are classified specifically by their uses like comb, wooden tablets, containers, etc., excavated from Haman Seongsansansung mountain fortress, which is the archaeological site of the Three Kingdoms era and those excavated from archaeological sites in Gyeongsang province considered to be the similar era of Haman Seongsansansung mountain fortress site. Wooden tablets and combs show the preferred species clearly and containers preferred wood species with the mid-ranged strength and the resistance against moisture migration.