• Korean Journal of Environment and Ecology
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• v.14 no.1
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• pp.38-45
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• 2000

This research has been done to investigate influence of soil physical and chemical properties on forest environmental change by fired pine forest in Koseong, Kangwondo. The sample sites were divided by not-fired sites(NF), not-cutting site after fired(FNC), cutting and planting sites after fired(FCP) and cutting and not-planting sites after fired(FC). Soil texture of whole sites was sandy clay loam. Sand content of NF top soil were lower than those of sub soil and clay content were higher, while FNC, FCP and FC sand content of top soil were higher than those of sub soil. Total porosity didn't differ between the sites. Coarse porosity and permeability had the increasing order as NF> FNC> FCP> FC, but fine porosity and bulk density had the opposite trends. Because forest fire removed the vegetation and then soil erosion was accelerated, forest environmental changes by forest fire greatly degraded soil porosity and permeability which were indices for forest water retention, so that soil physical properties were deteriorated. Both top and sub soil pHs of NF and FNC were higher than those of FCP and FC. Organic matter content and total nitrogen content of top and sub soils were high in order as NF> FNC> FCP> FC. Cation exchange capacities and exchangeable cation(K+, Na+, $Ca^2$+, $Mg^2$+) content in top soils were higher than those in sub soils, and in order as NF> FNC> FCP> FC, to be compared by the sites. Those mean that forest fire result from the erosion of top soil layers.

• Journal of Korean Society of Forest Science
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• v.4 no.1
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• pp.9-13
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• 1965

Powdery mildew of Ailanthus altissima Sw. was first reported by J.S. Park in Korea, 1961. According to his report, this disease was found on the leaves of this tree species collected in Jeongup, 1957, and in Taejon, 1958. He described morphological characters of this pathogen and described also that the causal fungus may be closely related with Phyllactinia corylea. This disease which appears dusty grayish yellow molds under surface of leaves was collected again by the author in Kwangju, 1962. The present works were undertaken to make clear the species of causal fungus by means of the morphology and pathogenecity. According to the following results, the pathogen was identified as Phyllactinia corylea (Pers.) Karst. Morphological characters of the fungus Mycelia persistent or more or less evanescent; matured conidia solitary, aseptate, short-clavate to clavate to clavate, hyaline or yellowish, granulate, $44.6-89.2{\times}9.3-24.2{\mu}$, average $64.8-17.8{\mu}$ in size; conidiophores elongate clavate or columnar, hyaline, 2-3 septate, $122.8-346.0{\times}3.7-7.4{\mu}$, average $208.8{\times}6.3{\mu}$; per-thecia usually scattered, rarely gregarious, dark brown to black, depressed globose to globose, $223.2-297.6{\mu}$, average $267.8{\mu}$ in diameter; appendages 12-19, usually 15 in number, hyaline, straight, needle-shaped, sharply pointed at the apex and bulbous at the base, aseptate, $93.0-310.0{\times}5.0-8.0{\mu}$, average $173.3{\times}6.4{\mu}$ in size; asci elongate ellipsoidal to broadly clavate, hyaline, more or less stalked, 8-13 in number, $68.5-76.6{\times}26.1-34.2{\mu}$, average $71.4{\times}29.0{\mu}$ in size; ascospores 2-4, usually 2 in number, hyaline or yellowish, aseptate, ellipsoidal or ovate, $27.7-34.2{\times}14.7-17.9{\mu}$, average $25.5{\times}13.9{\mu}$ in size. Pathogenicity of the fungi In order to make clear the species of the fungus and the pathogenic differences of Phyllactinia fungi which are collected around the contaminated area and seemed to be related to Ailanthus powdery mildew, some inoculation experiments were performed. 1. Cross inoculation to several tree species with their pathogen: Tested materials; Phyllactinia in question on Ailanthus altissima Sw. Ph. fraxini (DC.) Homma. On Alnus firma S. et Z. Ph. moricola (P. Henn.) Homma on morus alba L. According to the results of the experiments, the reactions were all negative with the exception of the original hosts of tested fungi. 2. Inoculation to Picrasma ailanthoides Planch. : The appearance of symptom on the leaves of P. ailanthoides is not distinct, but more or less mycelial growth. Therefore, under the optimal condition in glass chamber, it may be possible to success artificially.

• Journal of the Korean Society for Library and Information Science
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• v.24
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• pp.139-169
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• 1993

The major purpose of this study is to scrutinize and analyze various factors in numerous aspects of two different library systems for the visually handicapped, namely braille library and a special section for the visually handicapped in the public library system. The analyses may provide theoretical and conceptual framework on which strategies to enhance services for the visually handicapped is to be developed. More specifically, this study seeks (1) to examine a linkage between the degree of maintenance of staffs, collections, and equipment and the level of satisfactions of librarians and (2) to come up with more effective mechanisms of welfare services for the visually handicapped in each library system. This research is qualitative-descriptive and uses interview method. Fourteen libraries throughout the nation (4 public libraries with a reading room for the visually handicapped and 8 braille libraries) which had been in operation more than one year were selected as subjects for the research. Findings and results of the analyses are summarized as follows : 1. There seems to be general consensus that each of public and braille library has significant but, to a certain extent, different roles to play in order to enhance library services for the visually handicapped. Recruitment of qualified librarians, increase of the volume of collection, and enlargement of reading room space are noted as immediate concerns for the former. For the latter, it was suggested that increase of the number of staff for publishing, securing more equipments for pulication in braille, and wider scope as well as more variety of publications are the pressing problems at hand. 2. Both public and braille library employ one librarian for the visually handicapped who is required to have educational background in library science and special education. In addition, one must have competence in reading braille types. 3. Majority of reading rooms in those libraries is so small in physical aspect that size and number of seats are 66m2 and 15 seats respectively because circulation services are mainly in use due to the problem of inaccessibility which is commonly suffered by the visually handicapped. 4. Library services for the visually handicapped are heavily concentrated upon the large urban area. In fact, most of braille libraries are located in Seoul whereas a reading room for the visually handicapped in the public library system are exclusively placed in the large cities such as Inchon, Taejon, and Taegu. 5. All of the public library is neither equipped with necessary facilities to publish in braille nor secured supporting instruments which may facilitate library use for the visually handicapped. On the contrary, most of braille libraries are equipped with arrangements to publish in braille despite supporting devices are gererally lacking. 6. Consequently, provision of services In the public library is largely confined to reading and circulation of materials purchased from braille libraries while major task of braille libraries centers around publication and distributions of the reading materials in braille.

• The Journal of Natural Sciences
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• v.8 no.2
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• pp.181-189
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• 1996

We investigated the relationship between the attitudes and brand preference on the expression techniques of advertisement of underwears and actual buying. A total of 233 females living in Seoul and Taejon were surveyed to compare these points of five major underwear brands (Vivien, Ravora, Wacoal, Calvin Klein, Let'xes).The survey showed that the responders reacted more positively to the revolutionary advertising techniques of the Calvin Klein, and Let'xes than to the more conservative techniques of the Vivien, Ravora, and Wocoal.The most positive response was obtained from the Calvin klein's revolutionary techniques while the most negative response from the Ravora. The most preferred brand was the vivien, followed by the Calvin Klein, Wacoal, Ravora, and Let'xes. The degree of preference varied according to the demographic variables like age, schooling, income, occupation, and residential area. As for the motive of preference, the Calvin Klein ranked best in respect to shape, quality, advertisement, and comfortability. The price factor was best for the Ravora. The Let'xes ranked worst in all aspects. However, there was discrepancy between the attitudes on advertisement and the actual buying, this implying that the attitudes on advertisement did not seem to directly affect actual purchasing behavior.

• Journal of the Korea Concrete Institute
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• v.17 no.4 s.88
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• pp.581-586
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• 2005

High-performance concrete (HPC), which is particularly sensitive to self-desiccation, is required to be durable even in severe environmental conditions, i.e. costal area, cold district, etc. However, in recent years, some attention was particularly given to cracking sensitivity of high performance concrete at early age. It has been argued and demonstrated experimentally that such concrete undergoes autogenous shrinkage due to self-desiccation at early age under restrained condition, nd, as a result, internal tensile stress may develop, leading to micro cracking and macro cracking. This shrinkage-introduced crack produces a major serviceability problem for concrete structures. One possible method to reduce cracking due to autogenous shrinkage is the addition of expansive additive. Tests conducted by many researches have shown the beneficial effects of addition of expansive additive for reducing the risk of autogenous shrinkage-introduced cracking. However, the research on hydration model of expansion additive has been hardly researched up to now. This paper presents a study of the hydration model of Ettringite-Gypsum type expansive additive. As a result of comparing forecast values with experiment value, proposed model is shown to expressible of hydration of expansive additive.

• Journal of Korean Society of Forest Science
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• v.81 no.2
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• pp.164-176
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• 1992

This study was conducted to determine the toxic effects of air pollutants on landscaping trees, Pinus densiflora, Pinus koraierasis, Ginkgo biloba, Liriodeytdron tulipifera, Platanus occidentalis and their resistance to the pollutant toxicity in urban and industrial regions of Seoul and Taejon, Korea. Total sulfur content and superoxide dismutase activity were analysed in tree foliage of Pinus densiflora, Pinzes koraiensis, Ginkgo biloba, Liriodendron tulipifera, Platanus occidentalis. In addition, SOD activity was analyzed in the foliage of tree seedlings, i.e. Pinus densijlora, Pinus koraiensis, Ginkgo biloba, Liriodendron tulipifera, with the lurnigation of $SO_2$ in gas chamber 4 hours a day for six days. In all species total sulfur content and SOD activity had a positive correlation. Air pollutants accumulated in tree tissues were supposed to enhance the enzyme activity like SOD providing with the resistance mechanisms. Trees under the air pollution stress increased enzyme activity to develop internal self-resistance against pollutants, but after a critical point enzyme-activity decreased gradually and resulting in injury after all, Deciduous trees had greater filtration capacity than conifers and coniferous trees showed greater resistance against air pollutants than deciduous species. Foliage SOD activity was higher in polluted area than in unpolluted area for most species. Coniferous species and mature trees had higher SOD activity than deciduous seedlings. Especially Pinus koraiensis, Ginkgo biloba and Plcatanus occidentalis had higher SOD activity than other species. The tree species with the high SOD activity showed strong resistance against air pollutants. In 2nd-year needles of Pinus densiflora seedlings and current and 2nd-year needles of Pinus koraiensis seedlings containing high native SOD activity, SOD activity increased with the increase of $SO_2$ level. But in seedlings containing low native SOD activity, SOD activity increased at 0.5ppm $SO_2$ level while it decreased at 1.5 and 2.5ppm $SO_2$. Changes of SOD activity was different between species and in most species SOD seemed to participate in resistance mechanism.

• Progress in Medical Physics
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• v.9 no.3
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• pp.155-162
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• 1998

Ho-l66 was produced by neutron reaction in a reactor at the Korea Atomic Energy Institute (Taejon, Korea). Ho-l66 emits a high energy beta particles with a maximum energy of 1.85 MeV and small proportion of gamma rays (80 keV). Therefore, the radiation absorbed dose estimation could be based on the in-vivo quantification of the activity in tumors from the gamma camera images. Approximately 1 mCi of Ho-l66 in solution was mixed into the flood phantom and planar scintigraphic images were acquired with and without patient interposed between the phantom and scintillation camera. Transmission factor over an area of interest was calculated from the ratio of counts in selected regions of the two images described above. A dual-head gamma camera(Multispect2, Siemens, Hoffman Estates, IL, USA) equipped with medium energy collimators was utilized for imaging(80 keV${\pm}$10%). Fifty-nine year old female patient with hepatoma was enrolled into the therapeutic protocol after the informed consent obtained. Thirty millicuries(110MBq) of Ho-166-CHICO was injected into the right hepatic arterial branch supplying hepatoma. When the injection was completed, anterior and posterior scintigraphic views of the chest and pelvic regions were obtained for 3 successive days. Regions of interest (ROIs) were drawn over the organs in both the anterior and posterior views. The activity in those ROIs was estimated from geometric mean, calibration factor and transmission factors. Absorbed dose was calculated using the Marinelli formula and Medical Internal Radiation Dose (MIRD) schema. Tumor dose of the patient treated with 1110 MBq(30 mCi) Ho-l66 was calculated to be 179.7 Gy. Dose distribution to normal liver, spleen, lung and bone was 9.1, 10.3, 3.9, 5.0 % of the tumor dose respectively. In conclusion, tumor dose and absorbed dose to surrounding structures were calculated by daily external imaging after the Ho-l66 therapy for hepatoma. In order to limit the thresholding dose to each surrounding organ, absorbed dose calculation provides useful information.