• Journal of Korean Society of Forest Science
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• v.39 no.1
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• pp.35-46
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• 1978

The morphological characteristics of vascular bundle sheath occurring on the culm wall were investigated by using many species of Bambusa and Sasa in order to test new classification method for endomorphological charateristics of Bamboos. The results obtained were as follows. 1. As for the thickness of the culm wall in the culm, it was shown that the culm wall of the Bambusa becomes thinner in propertion to its nearness to the upper part of the tree, but no distinctive difference appeared in the Sasa. 2. It was shown that many species of Bambusa has a, b types but the Sasa had a' type and had a, b types. 3. It was shown that many species of Bambusa had e', h, and i types but the Sasa had not them and both of species had not f type. 4. It was shown that many species of Bambusa had c, d, e, and g types, but the Sasa had c, d, and e types and had not g type. 5. In the classification of Bambusa and Sasa, The method of the physiological classification was more effective than test of external observation, and it will encourage further study.

• Journal of the Korean Ceramic Society
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• v.49 no.4
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• pp.369-374
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• 2012

Based on the structure feature of a tree, a cylindrical $Ti_2AlC$/graphite layered composite has been fabricated through heat treating a graphite column and six close-matched thin wall $Ti_2AlC$ cylinders bonded with the $Ti_2AlC$ powders at $1300^{\circ}C$ and low oxygen partial pressure. SEM examination reveals that the bond interlayers between cylinders or that between cylinder and column are not fully dense without any crack formation. During the compressive test, the strain of the $Ti_2AlC$/graphite layered composite is about twice higher than that of the monolithic $Ti_2AlC$ ceramic, and the compressive strength of the layered composite is 348 MPa. The layered composite show the noncatastrophic fracture behaviors due to the debonding and shelling off of the layers, which are different from the monolithic $Ti_2AlC$ ceramic. The mechanism of the improved deformation capacity and noncatastrophic failure modes are attributed to the presence of the central soft graphite column and cracks deflection by the bond interlayers.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.11
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• pp.1612-1617
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• 2003

Synchrotron X-ray micro imaging technique was employed to non-invasively monitor the water flow inside xylem vessels in a bamboo leaf. The phase contrast X-ray images clearly visualized plant anatomy and the rise of a water front inside the vessels. Consecutive X-ray images taken for 60 seconds revealed water rise kinetics against gravity in the xylem of a cut dry leaf taken from a bamboo tree. For the first time, traces of water rise, variation of contact angle between water and xylem wall as well as the internal structure of xylem were obtained. In xylem vessels, a repeating flow pattern has a typical flow velocity of 30.7$\mu\textrm{m}$/s and faster flow is established intermittently. It is concluded that the transmission type of X-ray micro imaging can be used as a powerful tool to investigate the ascent of sap in the xylem vessels at a resolution higher than that of MRI.

• Tuberculosis and Respiratory Diseases
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• v.49 no.4
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• pp.508-513
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• 2000

The aspergillus tracheobronchitis is distinctive manifestation of invasive aspergillosis, in which infection is limited completely or predominantly to the tracheobronchial tree. It accounts for about 7 to 10 percent of cases of invasive disease. Grossly, such disease may take the mucosal exudate and obstruct partially the airway lumen or completely the occlusive mucous/fungus plugs. Microscopically, the superficial portion of the airway wall is acutely inflamed and contain fungal hyphae. However, infection is often limited to the mucosa. We report a case of aspergillus tracheobrochitis in a 54 year-old man who presented cough, progressive dyspnea with wheezing, and mucus plug. Bronchoscopy showed mucosal exudate and plug. Bronchoscopic biopsy showed aspergillus hyphae and inflammation in the mucosa. He was successfully treated with itraconazole.

• Journal of the Korean Institute of Landscape Architecture
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• v.28 no.4
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• pp.132-137
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• 2000

In June, the City of Seoul held a design competition for $\ulcorner$Seoul Park$\lrcorner$in Paris to promote friendly relations with its sister city. The purpose of this paper is to articulate the design concept of a scheme submitted by the author. The author interpreted the object of this design competition as follows: if we regards a park not as one of urban planning facilities but as a space for expressing a culture, $\ulcorner$Seoul Park$\lrcorner$in Paris is a space expressing Korean culture, or a culture of the City of Seoul in Paris, France. Three points were emphasized in this scheme: 1. Physical and non-physical aspects of Korean culture, or a culture of the City of Seoul were expressed separately. In physical part, a traditional Korean garden was reappeared to express its authenticity compared to its counterpart, French classical garden - its formal and grand style. In nonphysical part, Seoul's features and its citizen's facial expression were engraved on 'free standing walls' named 'Seoul Expression'. In addition, Korean traditional and modern performing arts will be performed in a square named as 'Seoul madang' surrounded by the free standing walls. 2. A space clearly divided by the fence was necessary to distinguish a traditional Korean garden from the place which looks like an amusement park. Traditional wall, mounding and pine tree groves were included. 3. Bamboo grove with the way taking a walk was introduced. The author expected that Parisian feels oriental mystery, the sound of wind, and the time lag of past and present in this sounding bamboo grove.

• The Journal of Korea Robotics Society
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• v.11 no.3
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• pp.115-126
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• 2016

This paper suggests the method of the spherical signature description of 3D point clouds taken from the laser range scanner on the ground vehicle. Based on the spherical signature description of each point, the extractor of significant environmental features is learned by the Deep Belief Nets for the urban structure classification. Arbitrary point among the 3D point cloud can represents its signature in its sky surface by using several neighborhood points. The unit spherical surface centered on that point can be considered to accumulate the evidence of each angular tessellation. According to a kind of point area such as wall, ground, tree, car, and so on, the results of spherical signature description look so different each other. These data can be applied into the Deep Belief Nets, which is one of the Deep Neural Networks, for learning the environmental feature extractor. With this learned feature extractor, 3D points can be classified due to its urban structures well. Experimental results prove that the proposed method based on the spherical signature description and the Deep Belief Nets is suitable for the mobile robots in terms of the classification accuracy.

• The Plant Pathology Journal
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• v.32 no.6
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• pp.563-569
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• 2016

The spatial patterns for temperature distribution on crape myrtle leaves infested with sooty mold were investigated using a digital infrared thermal imaging camera. The mean temperatures of the control and sooty regions were $26.98^{\circ}C$ and $28.44^{\circ}C$, respectively. In the thermal images, the sooty regions appeared as distinct spots, indicating that the temperatures in these areas were higher than those in the control regions on the same leaves. This suggests that the sooty regions became warmer than their control regions on the adaxial leaf surface. Neither epidermal penetration nor cell wall dissolution by the fungus was observed on the adaxial leaf surface. It is likely that the high temperature of black leaves have an increased cooling load. To our knowledge, this is the first report on elevated temperatures in sooty regions, and the results show spatial heterogeneity in temperature distribution across the leaf surface.

• 한국균학회소식:학술대회논문집
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• 2015.11a
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• pp.14-14
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• 2015

Cellular aspects of sooty mold on walnut leaves were investigated by using light and electron microscopy. A black coating developed on the adaxial leaf surface of a walnut tree. No infestations were found on the abaxial leaf surface with peltate glandular trichomes. Light microscopy showed that fungal complexes from the leaf surface were composed of brown conidia and hyphae. Conidia, with longitudinal and transverse septa, were variable in length ranging from 10 to $30{\mu}m$, and commonly found in clusters, forming microsclerotia. Neither epidermal penetration nor hyphal entrance to host tissues was observed. Based on their morphological characteristics, the fungal complexes were assumed to be Capnodium species. An electron-dense melanized layer was present on the cell wall of multi-celled conidia. Concentric bodies in the fungal cytoplasm had an electron-translucent core surrounded by an electron-dense margin with a fibrillar sheath. Chloroplasts without starch granules in the palisade mesophyll cells of sooty leaves had electron-dense stromata and swollen plastoglobuli. These results suggest that the epiphytic growth of fungal complexes can be attributed to the melanized layer and concentric bodies against a water-deficient environment on the leaf surface. Ultrastructural characteristics of the sooty leaves indicate typical features of dark-adapted and non-photosynthetic shade leaves.

• Journal of the Korean Wood Science and Technology
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• v.24 no.1
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• pp.1-10
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• 1996

The frequency distribution diagrams of Korean diffuse-porous woods, 36 families, 75 genera, 145 species, 215 specimens in relation to habit and phenology were analyzed. As the habit character changes from shrub to tree, such quantitative features as vessel frequency, percentage of solitary vessels, length/diameter(L/D) ratio of vessel element decreased but tangential vessel diameter, fiber length/vessel element length(F/V) ratio increased. Qualitative features such as helical vessel wall thickening, diffuse distribution of longitudinal parenchyma, heterogeneous ray composition decreased, while alternate intervessel pits, libriform wood fiber, simple perforations increase. As the phenology character changes from evergreen to deciduous species, such quantitative features as percentage of solitary vessels, vessel element length and L/D ratio decreased but tangential vessel diameter, F/V ratio increased. Diffuse distribution of longitudinal parenchyma, heterogeneous ray composition, and crystals in qualitative features decreased, while alternate intervessel pits, libriform wood fiber, simple perforation of vessel element, ray width and ray height increased.

• Parasites, Hosts and Diseases
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• v.58 no.6
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• pp.689-694
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• 2020

Strongyloidiasis is caused by Strongyloides stercoralis and is one of the most neglected tropical diseases in tropical and subtropical regions. Although several strongyloidiasis cases have been reported in Korea, genetic analysis of Korean isolates is still incomplete. In this study, a parasite was isolated from a 61-year-old man diagnosed with strongyloidiasis during the treatment of lymphoma on his retroperitoneal lymph node. Diffuse symmetric wall thickening from the ascending to descending colon and a nematode-infected intestine was observed following microscopic examination. Genomic DNA was isolated from a patient tissue block, and S. stercoralis was identified by PCR and sequencing (18S rDNA). In order to determine phylogenetic location of a Korean isolate (named KS1), we analyzed cox1 gene (500-bp) and compared it with that from 47 previous S. stercoralis isolates (28 human isolates and 19 canid isolates) from Asian countries. Our results showed that phylogenetic tree could clearly be divided into 5 different groups according to hosts and regions. KS1 was most closely related with the Chinese isolates in terms of genetic distance.