• 센서학회지
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• 제21권4호
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• pp.256-262
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• 2012

Hyaluronic acid(HA) hydrogels were synthesized by immersing HA microbeads in phosphate buffered saline solutions having different pH levels to assess the effect of pH on the swelling ratio of HA hydrogels for smart drug delivery systems. No beads were formed when the HA solution(below pH 9) was crosslinked with divinyl sulfone(DVS) because DVS is a basic solution. The variation regarding the size of the microbead was not significant, suggesting that the bead size is not a function of pH(10 ~ 14). However, the pore size of the microbeads decreased with increasing pH from 10 to 14, leading to the surface smoothness and dense network as a result of higher crosslinking. The swelling ratio of hydrogels increased when the pH rose from 2(acidic) to 6(neutral). Afterwards, it decreased with further increasing pH(basic). The lower swelling ratio may be due to the lack of ionization of the carboxyl groups. On the other hand, a higher swelling ratio is likely due to the increased electrostatic repulsions between negatively charged carboxyl groups on different chains. Experimental results suggested that pH-responsive HA hydrogels can be applicable to the controlled drug delivery systems.

• Applied Microscopy
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• 제42권4호
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• pp.212-217
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• 2012

This paper reports the effects of post-annealing of ZnO thin films on their microstructure and the device performance of the transistors fabricated from the films. From X-ray diffraction and transmission electron microscopy characterization, we uncovered that the grain size increased with the annealing temperature escalating and that the film stress shifted from compressive to tensile due to the grain size increment. Electrical characterization revealed that the grain size increase damaged the device performance by drastically lifting the off-current level. By annealing the devices in an $O_2$ ambient (instead of air), we were able to suppress the off-current while improving the electron mobility.

• 한국비블리아학회지
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• 제22권4호
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• pp.341-359
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• 2011

어린이자료 출판량의 급격한 증가에 따라 전문서평지가 갖는 선정도구로써의 역할은 더욱 중요해지고 있다. 본 연구의 목적은 외국의 어린이자료와 관련된 전문서평지를 분석함으로써 국내 어린이자료 전문서평지 개발에 기본적인 시사점을 제공하고자 하였다. 연구방법은 사례연구로써 이 분야에서 널리 알려진 국외 어린이자료 전문서평지 4개와 국내의 어린이자료에 대한 서평을 제공하는 도서관기관지 1개를 선정하여 조사 분석하였다. 연구결과에서는 구체적인 전문서평지의 구성요소와 기본틀을 관련 연구자 및 실무자들에게 제공하고자 하였다.

• 대한금속재료학회지
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• 제46권9호
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• pp.604-608
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• 2008

The layered compounds vanadium disulfide($VS_2$) and vanadium dioxide($VO_2$) intercalated with Li are investigated for using the Discrete Variational $(DV)-X{\alpha}$ molecular orbital method. The chemical bonding properties of the atoms were examined by bond overlap population of electronic states. The plot of density of states supports the covalent bonding properties by showing the overlap between the atoms. There is a strong tendency of covalent bonding between V-S and V-O. The intensity of covalent bonding of $VS_2$ is stronger than $VO_2$. The net charge of $LiVO_2$ is higher than that of $LiVS_2$. This results of the calculation of $VO_2$ and $VS_2$ indicate that $(DV)-X{\alpha}$ method can be widely applied in the new practical materials.

• Archives of Metallurgy and Materials
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• 제66권3호
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• pp.729-733
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• 2021

Ferrotitanium can be produced as a method of recycling Ti scraps. The eutectic composition of ferrotitanium, Fe_29.5Ti_70.5, can be obtained as a nanocrystalline phase due to relatively low melting point. Fe_29.5Ti_70.5 in which FeTi and β-Ti form a lamellar structure have high strength but low strain. To improve this, impurities were removed through hydrogen plasma arc melting (HPAM) and annealed. HPAM can remove substitutional/interstitial solid solutions. As a result, from 6733 ppm to 4573 ppm of initial impurities were removed by HPAM process. In addition, the strain was improved by spheroidizing and coarsening the lamellar structure through annealing. The effect of impurities removed through HPAM on the Young's modulus, yield strength, and strain was observed.

• 전기학회논문지P
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• 제58권4호
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• pp.369-373
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• 2009

Recently, the number of applicants for the engineering college is gradually decreased all over the nation. Additionally, the concerns of fall of freshman scholastic ability are raised due to the incomplete high school education. Moreover, the inferior circumstance and supports drive local universities into a corner. Therefore, the local universities endeavor in order to improve the quality of basic engineering education, and study the countermeasure against the crisis. In this paper, we derive several ideas in order to enhance the basic engineering education qualities. And the enhancement plans for the basic engineering education are proposed. Results in this paper will be helpful for engineering college to enhance the basic engineering education as reference materials.

• 복식
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• 제20권
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• pp.49-62
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• 1993

The purpose of this research was to utilize of Pattern Design System(P.D.S) by using AM-300 The conclusion were like these : 1. A coat of basic pattern was selected by design sketch. 2. The basic pattern was input into computer by digitizing. 3. The basic pattern was change into designed shape by using various skills. This system were enabled to draw straight lines, curves, delete lines, sections of lines, extend lines, cut pattern into sections, measure line or section reproduce whole pattern shape of section, rotate and mirror pattern and complete patterns. 4. Automatic grading of finished master pattern have been developed by creation and modification of grading rules of basic pattern. 5. Production pattern added seam allowance, not-ches was generated by P.D.S menu option. 6. Finished pattern design was plotted out 100% and 20% size by AM-300 Plotter. This results will be the basic materials to develop the CAD SYSTEM if some problems were improve. Furthermore, the utilization of P.D.S is expected to be developing in pattern making process.

• Food Science and Biotechnology
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• 제14권4호
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• pp.441-445
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• 2005

Pinitol and chiro-inositol exert insulin-like effect by mediating post-receptor signaling pathway. Total chiro-inositol concentrations, including pinitol, chiro-inositol, and their derivatives, were determined in 115 natural and food materials to identify economical sources for mass production of pinitol. Carob pod, Bougainvillea, soy whey, and soybean oligosaccharides were rich sources of chiro-inositol. Pinitol was isolated from soy whey and carob pod, considered as economically viable sources, by chromatographic separation using activated carbon. Soy and carob pinitols had same chemical structure as that of reference pinitol based on HPLC and NMR results. Oral administration of soy pinitol and carob pinitol (10 mg/kg) significantly decreased blood glucose at 2-6 hr in streptozotocin-induced diabetic rats. These results suggest pinitol isolated from soy whey and carob pod could be beneficial in controlling blood glucose in animal model of diabetes mellitus.

• 한국실내디자인학회논문집
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• 제16권4호
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• pp.47-53
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• 2007

As more serious environmental problems of buildings, many researchers have recognized the importance of preserving the environment where we live as well as a necessity of developing architecture with eco-environmentally. As a result, our country and some advanced countries have tried to solve these problems in that developed green building assessment tools for estimating environmental performance of buildings. Among many kinds of buildings, hospital which have been relation with human beings has been laking in basic raw materials of researching hospital's environment. Especially, there are few materials about indoor environment of hospital. So, the facilities of patients not only have to depend on the quality of natural environment but be also taken into account of patients. The purpose of this study is to prepare the basic data to develop the items of indoor environmental assessment for hospital to improve the quality of hospital's indoor environment. To come to a conclusion, we used a method of comparing domestic green building certification criteria, LEED v.2.2 and GBTool 2005. Then, we analyzed them for the case studies. Consequently, we could grasp basic data to assist in effecting domestic green building certification criteria for hopital. Furthermore, we have made a progressive research about setting grades of it.

• 패션비즈니스
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• 제23권5호
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• pp.19-30
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• 2019

The aim of this study is to analyze the stage of image change in Korean fashion design in regards to the simulacre of Jean Baudrillard. The changing phases of Korean fashion design are as follows: First, the initial stage involved simple imitation, which replicated the original as much as possible, it expressed the basic composition of Hanbok, flat cut and rich silhouette, the color scheme of traditional colors, traditional patterns, materials, and traditional ornaments. In the second stage, the subject matter intervened to distort and transform from the original, the basic composition and structure of the Hanbok were barely maintained, they were either removed or part of the structure modified or expressed using modern materials and patterns. The third stage, were based on reality but differed from reality through subject and imagination, and only left a part of the basic composition of Hanbok, and were expressed through the partial modification of the elements of the Hanbok, for instance the silhouette, skirt waist, collar and breast-tie. The fourth stage of pure simulacre, which refers to a new image with complete independence regardless of the reality. This stage differed from the basic structure and composition of Hanbok, and showcased traditional Korean image of Korea's unique cultural elements, such as hanbok or crafts and artworks, in a modern fashion with a modern sense and practicality.