• Journal of Korean Association for Spatial Structures
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• v.8 no.2
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• pp.22-28
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• 2008

• Proceedings of the Korean Geotechical Society Conference
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• 1994.09a
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• pp.235-246
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• 1994

At pre-construction design stage, most of the design data are based on the site investigation results or property estimation which often does not provide satisfactory output for the tunnel analysis. Nonlinear FEM tunnel analysis was cariied out by Hoek-Brown model which is principly semi-empirical design method based on insitu rock descriptions, rock test results as well as field measurement data. The results of the analytical methods from Hoek-Brown model and Mohr-Coulomb model are compared with the sige measurement data from two-NATM tunnel construction sites. It was found that the Hoek-Brown model can be satisfactorily adopted as a feed back analysis technique in order to examin the safety of NATM tunnel at any construction stage.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.05a
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• pp.64.2-64.2
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• 2011

Recently, Silicon Germanium (SiGe) alloys have been received considerable attention for their great potentials in advanced electronic and optoelectronic devices. Especially, microcrystalline SiGe is a good channel material for thin film transistor due to its advantages such as narrow and variable band gap and process compatibility with Si based integrated circuits. In this work, microcrystalline silicon-germanium films (${\mu}c$-SiGe) were deposited by DC/RF magnetron co-sputtering method using Si and Ge target on Corning glass substrates. The film composition was controlled by changing DC and RF powers applied to each target. The substrate temperatures were changed from $100^{\circ}C$ to $450^{\circ}C$. The microstructure of the thin films was analyzed by x-ray diffraction (XRD) and Raman spectroscopy. The analysis results showed that the crystallinity of the films enhances with increasing Ge mole fraction. Also, crystallization temperature was reduced to $300^{\circ}C$ with $H_2$ dilution. Hall measurements indicated that the electrical properties were improved by Ge alloying.

• Proceedings of the KIEE Conference
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• 2002.11c
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• pp.329-332
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• 2002

Recently, most machineries have been small size and mobile type. Then the motors used in this field are developed in micro size such as about 2mm in diameter. The structure of this motor is similar to a general brushless DC motor but because of small sige there is no position sensor such as hall sensor. In this paper, we propose synchronous driving and control method for micro brushless DC motor without position sensor. We design and manufacture this controller and perform experiment to show the effectiveness of the proposed method.

• Journal of Sericultural and Entomological Science
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• v.33 no.1
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• pp.27-31
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• 1991

Microsporidian spores were isolated from yellow-hind winged arctiid, Eilema griseola (Hubner), and cutworm, Agrotis tokionis Butler, and their morphological characteristics and their indectivity to silkworms were investigated. The shape of the microsporidian isolates was oval and the sige of the spore isolated from yellow-hind winged was measured in 2.6$\times$1, 5$\mu$ and that of the isolated from cutworm was measured in 3.7$\times$20.$\mu$. Both the isolated microsporidians showed the infectivity to silkworms, but the isolates did transovarian transmission in silkworms and the silkworm moth infected with the isolate from yellow-hind winged laid eggs irregularly.

• Journal of radiological science and technology
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• v.1 no.1
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• pp.69-73
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• 1978

This study was conducted in order to determine width, length of lung by radiographic method. The measurements carried out on normal chest X-ray film of 1,036 persons who took the radiograph from the April of 1977 to the June of 1978. As a result of this study, the following conclusions were obtained: 1. In the case of male, the average width, and length of both side lung size from new birth to nineteen of age was larger than female with the exception of partly age group. 2. Lung size in average width at adult was from 27.60cm to 29.20cm and female was 25.10cm to 26.22cm. 3. The mean length of left lung at adult was from 26.32cm to 25.27cm in female. 4. The average length of right lung at adult was from 25.8cm to 28.35cm in male and female was from 24.86cm to 25.17cm. 5. It was found that lung sige in width and length was slightly increased until 39 years of age, but was trend to decrease it of lung in the age of 40 years old. 6. In the case of adult, the difference of the average length between right and left lung, the length of right lung was slightly shorter than left that.

• Journal of the Korean Home Economics Association
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• v.27 no.1
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• pp.97-109
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• 1989

The purpose of this study was to find out change of the apartments stouge space in Seoul area from 1971 to 1988. It also attempts to compare the storage space in the apartment with the optimum storage space which is suggested by precedent studies on the storage space. Content analysis methods were used to analyze 961 apartment floor plan from the booklet of 'Apartment Information'. The major findings were as follows : 1) According to the precedent studies, optimum storage spaces are 3.86∼7.72㎡ for 66.07∼115.61㎡ house, and 14.23∼20.31㎡ for 115.62∼165.15㎡ house. 2) It was found out that the storage spaces of the apartments were increased until 1977∼80 and decreased after 1980. 3) Comparing the storge space with the optimum standard, most of the apartments have not enough storage space. It offers only 50% of optimum storage space. 4) The percentage of installation of storage space in bedrooms were quite low in general. Specially, bedrooms in small apartment under 66.6㎡ and most master bedrooms didn't storage spaces. 5) The sige of the apartment storage space were variant according to the builder. Only one builder from 8 offered the spaces close to the optimum standrd, and others didn't seem much care for the storage space.

• Progress in Medical Physics
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• v.3 no.1
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• pp.25-34
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• 1992

For the TBI with medical linear accelerator(6.10MV), we measured basic data for dosage calculation and designed compensation filters to improve dose uniformity. At the distance of 3.4cm from the source, using the specially designed compensation filters reduced with in ${\pm}$5% for mid-depth dose in the phantom seated with flexion of the legs in the field sige up to 120${\times}$120cm$^2$ for the whole body. In repeated measurements for the dose distribution with humanoid phantom contained paraflin compound, measurement error using the TLD chips were less than ${\pm}$5%.

• Analytical Science and Technology
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• v.27 no.6
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• pp.277-283
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• 2014

The effects of concentration, pressure, and molecular sige on removing allergenic substance (phospholipase $A_2$) in bee venom by ultrafiltration were investigated. The membrane pore sizes were selected based on the molecular weight of the main compounds. The conditions of concentration and pressure were selected randomly. As results, we obtained the optimum condition (1 mg/mL, 20 psi, 10,000 dalton) for removing $PLA_2$ at constant concentration of melittin and apamin and confirmed the separation results by HPLC and SDS-PAGE.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.4A
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• pp.415-422
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• 2004

DSRC provides high speed radio link between Road Side Equipment and On-Board Equipment within the narrow communication area. In this paper, a 5.8 GHz down-conversion mixer for DSRC communication system was designed and fabricated using 0.8 ${\mu}{\textrm}{m}$ SiGe HBT process technology and RF/LO matching circuits, RF/LO input balun circuits, and If output balun circuit were all integrated on chip. The chip size of fabricated mixer was 1.9 mm${\times}$1.3 mm and the measured performance was 7.5 ㏈ conversion gain, －2.5 ㏈m input IP3, 46 ㏈ LO to RF isolation, 56 ㏈ LO to IF isolation, current consumption of 21 mA for 3.0 V supply voltage.