• The Optical Journal
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• s.117
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• pp.23-25
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• 2008

RF embedded 기판의 기술은 Module과 Package라는 응용 제품을 거치면서 최종적으로는 기존의 여러 가지 제품의 Mother Board(특히 휴대폰)에 접목 시키기 위한 노력이 계속 진행되고 있다. 업계 및 Research 기관의 조사 결과에 따르면 PCB 시장의 성장세와 맞물려 Embedded 시장규모는 큰 폭의 상승이 예상된다. 본 고에서는 높은 유전율을 가지는 강유전체 물질의 Embedded capacitor 적용을 위해 레이저 기술을 전자부품 제조현장에 적용하는 연구의 진행상황을 소개하고자 한다.

• KOMUNHWA
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• no.58
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• pp.25-84
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• 2001

This study investigated about the Panchuk Earth Wall that is the Hardened-Heaped Earth Wall, which was surveyed in the South Korea area. The Panchuk Earth Wall was classified into the 2 types depending on the existence and nonexistence of Seok-yeol(石列), t

• Biomedical Science Letters
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• v.3 no.1
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• pp.21-28
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• 1997

Male rats of Albino strain were divided into four groups, control group, X-irradiated group, WR-2721 treatment group and X-irradiated group treated with WR-2721. The radioprotective effect of treatment with S-2 (3-aminopropylamino)ethylphosphorothioic acid (WR-2721) in the dose of 200mg/kg by intraperitonial injection on rats 20min prior to wholebody X-irradiation (8Gy) was studied. Each group determined serum alkaline phosphatase (ALP), aspartate aminotransferase (ASI), alanine aminotransferase (ALT), lactate dehydrogenase (LDH) activities and contents of serum glucose after 1, 3, 7 and 10 days. The ALP and AST activities of X-irradiated group were significantly decreased (p<0.05) compared with that of control group, but X-irradiated group treated with WR-2721 less decreased those enzyme activities compared with the X-irradiated group. X-irradiated group was significantly increased (p＜0.05) ALT and LDH activities compared with that of control group, but X-irradiated group treated with WR-2721 less increased those enzyme activities compared with the X-irradiated group. The concentration of serum glucose of X-irradiated group was significantly increased (p<0.05) compared with that of control group, but X-irradiated group treated with WR-2721 less increased compared with that of X-irradiated group. It may be considered that WR-2721 provided radioprotective effect of organs of body from X-irradiation.

• Korean Journal of Ecology and Environment
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• v.55 no.4
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• pp.368-375
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• 2022

Gut contents analysis is essential to predict the impact of organisms on food source changes due to variations of the habitat environment. Previous studies of gut content analysis have been conducted using traditional methods, such as visual observation. However, these studies are limited in analyzing food sources because of the digestive process in gut organ. DNA metabarcoding analysis is a useful method to analyze food sources by supplementing these limitations. We sampled marine fish of Pennahia argentata, Larimichthys polyactis, Crangon affinis, Loligo beka and Sepia officinalis from Gwangyang Bay and Yeosu fisheries market for analyzing gut contents by applying DNA metabarcoding analysis. 18S rRNA v9 primer was used for analyzing food source by DNA metabarcoding. Network and two-way clustering analyses characterized the relationship between organisms and food sources. As a result of comparing metabarcoding of gut contents for P. argentata between sampled from Gwangyang Bay and the fisheries market, fish and Copepoda were analyzed as common food sources. In addition, Decapoda and Copepoda were analyzed as common food sources for L. polyactis and C. affinis, respectively. Copepoda was analyzed as the primary food source for L. beka and S. officinalis. These study results demonstrated that gut contents analysis using DNA metabarcoding reflects diverse and detailed information of biological food sources in the aquatic environment. In addition, it will be possible to provide biological information in the gut to identify key food sources by applying it to the research on the food web in the ecosystem.

• Radiation Oncology Journal
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• v.16 no.3
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• pp.337-345
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• 1998

Purpose : To obtain the uniform dose at limited depth to entire surface of the body, the dose characteristics of degraded electron beam of the large target-skin distance and the dose distribution of the six-dual electron fields were investigated Materials and Method : The experimental dose distributions included the depth dose curve, spatial dose and attenuated electron beam were determined with 300 cm of target-skin distance (TSD) and full collimator size (35*35 $cm^2$ on TSD 100 cm) in 4 MeV electron beam energy. Actual collimated field size of 105 cm * 105 cm at the distance of 300 cm could include entire hemibody. A patient was standing on step board with hands up and holding the pole to stabilize his/her positions for the six-dual fields technique. As a scatter-degrader, 0.5 cm of acrylic plate was inserted at 20 cm from the body surface on the electron beam path to induce ray scattering and to increase the skin dose. Results : The full width at half maximum(FWHM) of dose profile was 130 cm in large field of 105*105 $cm^2$ The width of $100\pm10\%$ of the resultant dose from two adjacent fields which were separated at 25 cm from field edge for obtaining the dose unifomity was extended to 186 cm. The depth of maximum dose lies at 5 mm and the 80$\%$ depth dose lies between 7 and 8 mm for the degraded electron beam by using the 0.5 cm thickness of acrylic absorber. Total skin electron beam irradiation (TSEBI) was carried out using the six dual fields has been developed at Stanford University. The dose distribution in TSEBI showed relatively uniform around the flat region of skin except the protruding and deeply curvatured portion of the body, which showed excess of dose at the former and less dose at the latter. Conclusion : The percent depth dose, profile curves and superimposed dose distribution were investigated using the degraded electron beam through the beam absorber. The dose distribution obtained by experiments of TSEBI showed within$\pm10\%$ difference except the protruding area of skin which needs a shield and deeply curvatured region of skin which needs boosting dose.

• Spatial Information Research
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• v.3 no.2
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• pp.91-102
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• 1995

The purposes of this paper are to find ways to detect ecotone between two eco'||'&'||'not;systems, measure the width and size of ecotone around the Mt. Pukhansan National Park, and investigate environmental impacts, if any, on the forest ecosystem of the park by human activities. Normalized Difference Vegetation Index(NDVI) derived from TM data and the ana'||'&'||'not;lytical capabilities of GIS are used to investigate characteristics of the ecotone, or the impact zone, of the park. Major findings of the study can be summarized as follows: First, it was found that ecotone of the park could be identified from NDVI -distance curves deri"ed by a series of buffering op'||'&'||'not;erations. Second, NDVIs of all three years of the national park are about 14 percent higher than surrounding areas. Third, width of ecotone were found to be closely related to phenology, adjacent land use, environmental degradation, etc. Third, ecotone of the study area was nearly douvled during 1985-1993 period, which might be caused by heavy trampling of visitors. Thus it can be concluded that further studies are needed to find exact causes of the deterioration of plant communities of the ecotone of the park.

• Korean Journal of Environment and Ecology
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• v.5 no.1
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• pp.91-103
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• 1991

Use impacts on environmental deteriorations of trail and campsite were studied in Chirisan National Park in 1991. The entire width, bare width and maximum depth of trail as the trail condition were significantly greater on the more heavily used trail. Trail conditions, especially altitude, entire width and maximum depth of deteriorated points which were surveyed at the total of 82 were significantly different from those of non-deteriorated points. On the ridge trail, the damaged are more severe than Class 4 reaches about 34,000$m^2$ and use impacts on campsite and deterioration were also accelerated. The dominant trees of the upper layer in trail edge vegetation are changed from Carpinus tschonoskii to Quercus serrata, Carpinus laxiflora and to Quercus mongolica, Carpins laxiflora at Hwaeomsa trail, and from Quercus serrata to Quercus mongolica at Piagol trail. Also Lespedoza maximowiczii, Symplocos chinensis, Deutzia prunifolia, Weigela Subsessilis appear as the dominant lower species at Hwaeomsa trail, L. maximowiczii, S. chinensis, Stephanandra incisa, Rhododendron schlippenbachii for Piagol trail.

• Korean Journal of Plant Taxonomy
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• v.38 no.2
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• pp.93-109
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• 2008

The morphological variation was analysed to examine previous hypotheses on the taxonomy of B. amurensis complex which includes B. amurensis Rupr. var. amurensis, B. amurensis var. quelpaertensis (Nakai) Nakai and B. amurensis var. latifolia Nakai. The results from the univariational and principal components analyses employing 22 putatively diagnostic characters indicate that B. amurensis var. quelpaertensis is distinct from var. amurensis in the length and width of leaves, angle of leaf apex, distance between spinose teeth, length of internode, number of flowers per inflorescence, whereas B. amurensis var. latifolia is different from other varieties in the angle of leaf apex and leaf length/width ratio. In principal component analysis, the characters of the leaf including leaf width and length were the main characteristics to distinguish those three taxa. The evidence both from the principal components analyses and current geographical distribution pattern suggest that retaining the varietal status for the two taxa, B. amurensis var. latifolia and B. amurensis var. quelpaertensis is reasonable.

• Journal of the Korean Magnetics Society
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• v.15 no.6
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• pp.320-324
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• 2005

The core loss of $3\%$ SiFe is strongly dependent on silicon content, impurities, permeability, and domain structure of the SiFe. Domain refining has been proved to be very good method for reduction of core loss in high permeability grain oriented SiFe, and laser scribing is well-blown as an effective and industrially important method of domain refinement. In this work, magnetic domain refinement has been carried out by using a pulsed Nd : YAG laser, and the core losses have been measured and analyzed to and optimal parameters of the laser treatment. The laser hem was focused with a spot size of $100{\mu}m$ and pulse energy of 10${\~}$35mJ and the lines were scribed with a period of ${\~}$5mm. The core loss was improved up to $17\%$ with 30 ns-Nd : YAG laser beam in $3\%$ SiFe.

• Fire Science and Engineering
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• v.19 no.2 s.58
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• pp.8-12
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• 2005

A fire in a clean room may cause a serious loss by spreading smoke particles. The effects of the width of smoke curtains on delay in smoke spread, which is located the work area boundaries, were investigated by using a computational fluid dynamics, for loss prevention by smoke spreading from one fire area to another. The fire scenario was set to a 1 MW methanol fire in a space of $30m\times10m$ floor and 4 m high. Distributions of temperature and smoke particles were compared for the width of the smoke curtains 0 (without smoke curtains), 1, 2, 3m. It was confirmed that a larger width of the smoke curtain delays spread of smoke more, and that making the work areas compartments is necessary to confine the smoke in the fire area.