• The Journal of Korean Society for Radiation Therapy
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• v.25 no.2
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• pp.175-180
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• 2013

Purpose: Modern radiation therapy technique such as IGRT has become a routine clinical practice on LINAC for decrease patient's set-up error. CBCT can be used to adjust patient set-up error and treat patient more accurately. The Purpose of this study is to evaluate field size of CBCT for improving Image quality and suggest reference date of CBCT field size. Materials and Methods: Image date were acquired using KV CBCT and Catphan phantom (Half fan and full fan mode were scanned from 2 ~16 cm, at intervals of 2 cm). Field size were categorized by Small field size (2 cm, 4 cm), Medium field size (8 cm, 10 cm), Large field size (more than 14 cm) and evaluate. To estimated the CTDi using CTDi phantom and Ion chamber. Results: CT number linearity of Small and Large field size are greater than Medium field size. Spatial resolution are not significantly different without Small field size. But half fan mode is more different than full fan mode. In full fan, except Medium field size, all field size exceed recommendation for HU uniformity. But half pan has stability for all field except Small field size. CTDi makes radical sign function graph in Medium field size. Conclusion: The worst result was given by Small field size for Image quality and practically. Medium field size can be useful to prevent patient from radiation exposure and give better Image quality. So this study recommends that Medium field size (8~10 cm) is more suitable for CBCT.

• Journal of the Korean Institute of Intelligent Systems
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• v.16 no.3
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• pp.297-302
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• 2006

In this paper, a method and system to compensate vertical component of 3-dimensional magnetic field sensor using the earth's field was described. Output of magnetic field sensor have a output offset that is generated setting angle error of magnetic sensor and gain error. Thus, to using the magnetic field sensor, it must be compensated. The compensation of magnetic field sensor is required at shield space. However, using the earth's field, output offset of the sensor can be simply compensated. And, we designed system for compensation of the sensor. The proposed method and system are verified usefulness through experimental.

• The International Journal of Costume Culture
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• v.13 no.2
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• pp.141-153
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• 2010

Fashion needs to be understood as practicality and creative behavior and various movements of paintings act as inspirations of original design for fashion designers. This study seeks to find sources of fashion designs in the works of Mark Rothko who is in the center of color-field abstract. Color-field of Rothko provides infinite inspirations as colors are identically treated as shapes and lighting and textures are all included on top of it. In this study, the purpose is to create color focused artistic fashion design by exploring the possibility of expression with the colors of Rothko as the main motive. The study method is as follows. First, the concept and significance of color-field abstract are researched through documented data. Works of Rothko is divided into three periods according to their characteristics. The background of the formation of color-field abstract of Rothko is understood by analyzing the trends of the works in each period. Second, twenty representative works from 1949 to 1969 are selected and analyzed in formative components of color, shape and textures in order to more accurately understand shape of colors, brilliance, simplicity that appear in the mature color-field abstract of Rothko. Third, preexisting methods of color-field of paintings developed into motives of clothing are studied focusing on the collections from 1997 to 2006. Examples of applications of color-field images in modern fashion designs are analyzed. Fourth, motives are selected based on general characteristics of color-field abstract of Rothko and the results of the formative analysis. Clothing is produced that expresses the colors of the paintings of Rothko more effectively. As the results of the study, restrained shapes and textures and various forms of color combinations shown in color-field abstract of Rothko provided deep inspirations on material composition and color planning for fashion design focused on colors. Additionally, needle-punching technique using wool for the production technique enabled relief texture expressions of materials by colors and effective applications of soft and warm atmosphere of color-field abstract of Rothko on clothing. Especially, the ideology of color-field abstract of Rothko of shaping of colors could be expressed and the direction of the development of motives could be presented at the same time by specifically applying color combination method using horizontal division of atypical color-field from the formative characteristics of color-field abstract of Rothko.

• Journal of Information Display
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• v.2 no.3
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• pp.78-85
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• 2001

The growth of carbon nanotubes(CNTs) in anodic aluminum oxide(AAO) template and their application to a field emitter are described. AAO templates were fabricated by anodizing bulk aluminum and sputtered thin Al film on Nb-coated Si wafers. After Co catalyst had been electrochemically deposited into the bottom of the pores in AAO template, CNTs were grown by pyrolyzing $C_2H_2$. Depending on the reaction conditions, CNTs grew up to or over the top of the pores in AAO template with different structures. The morphology and structure of CNTs were observed with a scanning electron microscope and a transmission electron microscope. The diameter of CNTs strongly depended on the size of the pores in AAO template and the growing conditions. The electron field emission measurement of the samples resulted in the turn-on field of 1.9-2.2 $V/{\mu}m$ and the field enhancement factor of 2450-5200. The observation of high field enhancement factors is explained in terms of low field screening effect.

• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.5
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• pp.43-57
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• 2003

This paper presents the air corridor planning strategy based on simulation with MUKLMO_3 (Micro-scale Urban Climate Model) to investigate the wind field and air corridor caused by the land-use change of the New Town Development Area in Pan-Gyo. In the first part, the most frequently observed wind field in the New Town Development Area was measured and used as an initial value to simulate a more realistic wind field and air corridor. Several experiments with different initial values of wind fields were carried out to investigate the wind field change affected by the New Town Development. The results show the features of the wind field of the neutral stability condition in the urban canopy layer with a high resolution near the ground. The wind speed is weakened at this level due to the New Town Development. It was found that the wind field and air corridor are influenced by the land-use change. After the development of the New Town, the speed of the wind field decreased and the main wind directions and air corridor changed. In this study, this model is found to be a useful tool for evaluating air corridor and change of wind field in speed and direction.

• Journal of the Korean Society of Tobacco Science
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• v.22 no.1
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• pp.61-70
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• 2000

This study was carried out to improve the tobacco field condition and to determine the effect of lime amount and application time on soil pH, yield, and quality of leaf tobacco. Lime was applied to the tobacco field by determined amounts according to different pH level. The changes of soil pH, growth of tobacco, yield, and quality of KF109 and Br21 tobacco were surveyed by time lapse. The target pH value in tobacco field soil can be reached at 6 weeks after lime application, and then the soil pH was lowered slightly after that time. The lime amount needed to reach target pH was decreased 40 % in the same tobacco field after 1 year. Though the initial growth rate of flue-cured tobacco in the field of pH 7.0 was lower than that of conventional tobacco field, the field of pH 7.0 showed the highest yield after the maximum growth stage. The quality of cured leaf tobacco in the field of pH 7.0 applied lime at spring season was slightly lowered compared with that in conventional. This results indicated that the best pH condition in tobacco field for the best tobacco growth was 6.5 and the proper time of lime application was fall season of previous year by application of the whole quantity.

• Structural Monitoring and Maintenance
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• v.7 no.4
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• pp.367-392
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• 2020

The specific characteristics of near-field earthquake records can lead to different dynamic responses of bridges compared to far-field records. However, the effect of near-field strong ground motion has often been neglected in the seismic performance assessment of the bridges. Furthermore, damage to horizontally curved multi-frame RC box-girder bridges in the past earthquakes has intensified the potential of seismic vulnerability of these structures due to their distinctive dynamic behavior. Based on the nonlinear time history analyses in OpenSEES, this article, assesses the effects of near-field versus far-field earthquakes on the seismic performance of horizontally curved multi-frame RC box-girder bridges by accounting the vertical component of the earthquake records. Analytical seismic fragility curves have been derived thru considering uncertainties in the earthquake records, material and geometric properties of bridges. The findings indicate that near-field effects reasonably increase the seismic vulnerability in this bridge sub-class. The results pave the way for future regional risk assessments regarding the importance of either including or excluding near-field effects on the seismic performance of horizontally curved bridges.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.12
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• pp.4891-4895
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• 2010

RF coil is an important component of the Magnetic Resonance Imaging (MRI) system and the performance of RF coil is one of major factors for high SNR images. Sensitivity and RF field uniformity are parameters for evaluating RF coil performance. Since the B1 field is induced by RF coil, MR signal is strongly affected by RF coil structure and arrangement. In receiving MR signal, the RF coil sensitivity to MR Signal is also determined by the induced B1 field of RF coil. Therefore, the spatial distribution of B1 field must be verified. In this work, we performed computer simulation of the basic RF coil structures using Matlab and verified their sensitivity and uniformity through their B1 field distribution. This work will be useful for the advanced multi-channel RF coil design.

• Journal of Applied Biological Chemistry
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• v.57 no.4
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• pp.331-336
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• 2014

Sediment and nutrient loading caused by the forest to conversion of agricultural lands have led to the deterioration in near water ecosystem. This study was carried out to examine the effects of agroforest culture field and open field culture field on water quality and runoff loading of nutrient. The runoff loading of Tot-N and Tot-P in agroforest culture field were similar to open field culture field. The runoff loading of total suspended solids (TSS) in agroforest culture field and open field culture field were $2,721kg{\pm}196/10a$ and $420{\pm}29kg/10a$ in 2011 and $696kg{\pm}59/10a$ and $463{\pm}36kg/10a$ in 2012, respectively. Our investigation showed that the runoff loading of TSS from agroforest culture field decreased when soil cover and soil stabilization increased. Therefore, protect facility of soil erosion for early alteration of agricultural lands are needed to minimize the soil erosion from agroforest culture field.

• Journal of the Korean Society for Library and Information Science
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• v.51 no.2
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• pp.133-156
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• 2017

This study was performed to find out how to improve the usefulness and effectiveness of the field practice program in Library and Information Science by diagnosing the practical instructor's perception of the overall field practice in the Library and Information Science. To achieve this goal, we conducted a research on the current situation and a measurement in perception of the field practice program through a survey of practical instructors at practical training institutions. We, then, analyzed the factors affecting the perception and examined the relationship between the effects. As a result of investigating the factors affecting the perception of field practice, 'operational accountability for the field practice program' was found to be a significant factor among other factors such as the general characteristics of the practical instructors, the characteristics of library related work and the field practice status of the practical training institutions. And factors of 'practice environment' and 'practice instruction method' have been identified to have a significant impact as a result of analyzing how the six factors constituting the perception of field practice effect on the overall perception of field practice of the practical instructors.