• Journal of Powder Materials
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• v.25 no.1
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• pp.12-18
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• 2018

Cost-effective functional phosphor nanoparticles are prepared by introducing low-cost $SiO_2$ spheres to rare-earth phosphor ($YVO_4:Eu^{3+}$, $YVO_4:Er^{3+}$, and $YVO_4:Nd^{3+}$) shells using a sol-gel synthetic method. These functional nanoparticles are characterized by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, and general photoluminescence spectra. The $SiO_2$ sphere occupying the interior of the conventional phosphor is advantageous in significantly reducing the cost of expensive rare-earth phosphor nanoparticles. The sol-gel process facilitates the core-shell structure formation; the rare-earth shell phosphor has strong interactions with chelating agents on the surfaces of $SiO_2$ nanoparticles and thus forms layers of several nanometers in thickness. The photoluminescence wavelength is simply tuned by replacing the active materials of $Eu^{3+}$, $Er^{3+}$, and $Nd^{3+}$. Moreover, the photoluminescent properties of the core-shell nanoparticles can be optimized by manipulating the specific contents of active materials in the phosphors. Our simple approach substitutes low-cost $SiO_2$ for expensive rare-earth-based phosphor materials to realize cost-effective phosphor nanoparticles for various applications.

• Journal of Applied Biological Chemistry
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• v.63 no.3
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• pp.229-234
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• 2020

Beer production with rice or other malt substitutes suffers from a lack of suitable enzymes for saccharification. For this reason, rice nuruk (fermentation starter) was tested as a starch replacement for malt in the saccharification process of beer production. The results of this study show that the enzyme activities of rice nuruk made with brewing fungi were higher than those of malt. Saccharification and glucoamylase activities were high in Aspergillus awamori KCCM 30790 and α-amylase activity was high in Aspergillus oryzae CF1003. Overall, malt beer had significantly higher alcohol, pH, total acid, volatile acids, amino acids, free amino nitrogen, bitterness unit and ΔE than rice nuruk beer. Where as Aspergillus awamori KCCM 30790 beer had significantly higher soluble solids, reducing sugar than malt beer. According to a sensory evaluation, malt beer was better color, flavor and Aspergillus oryzae CF1003 beer was better taste, texture, overall acceptability than other beer. Therefore Aspergillus awamori KCCM 30790 beer was suitable considering enzyme activities (saccharification, glucoalmylase) and physicochemical characteristics (soluble solids, reducing sugar). And then Aspergillus oryzae CF1003 beer was suitable considering sensory evaluation (taste, texture, overall acceptability). Therefore rice nuruk like Aspergillus awamori KCCM 30790 and Aspergillus oryzae CF1003 were suitable as a substitute material that can replace for malt in beer proceccing.

• Journal of Biomedical Engineering Research
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• v.37 no.3
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• pp.105-111
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• 2016

Introduction: Surgical robot is the alternative instrument that substitutes the difficult and precise surgical operation; should have intuitiveness operationally to transfer natural motions. There are limitations of hand motion derived from contacting mechanical handle in the surgical robot master interface such as mechanical singularity, isotropy, coupling problems. In this paper, we will confirm and verify the feasibility of intuitive Non-restraint master interface which tracking the hand motion using infra-red camera and only 3 reflective markers without the hardware handle for the surgical robot master interface. Materials & methods: We configured S/W and H/W system; arranged 6 infra-red cameras and attached 3 reflective markers on hands for measuring 3 dimensional coordinate then we find the 7 motions of grasp, yaw, pitch, roll, px, py, pz. And we connected Virtual-Master to the slave surgical robot(Laparobot) and observed the feasibility. To verify the result of motion, we compare the result of Non-restraint master and that of clinometer (and protractor) through measuring 0~180 degree, 10degree interval, 1000 samples and recorded standard deviation stands for error rate of the value. Results: We confirmed that the average angle values of Non-restraint master interface is accurately corresponds to the result of clinometer (and protractor) and have low error rates during motion. Investigation & Conclusion: In this paper, we confirmed the feasibility and accuracy of 3D Non-restraint master interface that can offer the intuitive motion of non-contact hardware handle. As a result, we can expect the high intuitiveness, dexterousness of surgical robot.

• The Journal of the Korea Contents Association
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• v.16 no.12
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• pp.772-780
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• 2016

This study examined the politics of representation about North Korean female defectors in general programming channels. In that channel's programs, the women are established as soften private people who got a lift in capitalism aggressively and as disparate subject that have value to be consumed by mass audience. They are caricatured with the testimony and internal competition, be emphasized that heterogeneous object. General programming channels use the women as easy and cheap substitutes for foreigners, also objectifies them to complies with the patriarchal authority. General programming channels are continuously producing a story to deal with North Korean female defectors in disparate subject. In this way, they owns the time and qualification to talk to the women as objects to be displayed, to ensure the media power. Ultimately, the female defectors is only a consumption subject that being sensuously staring, so they remain 'other' instead of 'us'.

• The Journal of the Korea Contents Association
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• v.5 no.6
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• pp.343-350
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• 2005

During the design of a successful digital watermarking systems, Pseudo-Noise(PN) sequences are widely used to modulate information bits into watermark signals. In this method, the number of bits that can be hidden within a small image by means of frequency domain watermarking is limited. In this paper, we show the possibility of introducing chaotic sequences into digital watermarking systems as potential substitutes to commonly used PN-sequences. And we propose a method that transforms the text to chaotic sequence. In our current implementation, we show how the sample text is expressed by an implied unit data(watermark) and the implied unit data is regenerated into the original left. Because we use this implied data as watermark for information hiding, we can insert much more watermark compared with previous method.

• Journal of Haehwa Medicine
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• v.4 no.2
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• pp.333-333
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• 1996

Chinese medicine is a precious treasure inherited from ancient ancestors. It is accredited for the prosperous growth of the Chinese nations. However, the descriptions of the herbs in the ancient herbal are not in detail and the great numbers of herbs used which grows in wide geographic areas together with various local folk names, new substitutes and new folk medicines had increased, many Chinese herbs are composed of herbs that are labeled with identical names but actually are of different origins and different grades. Similar situation had occurred in China, japan and Korea In Taiwan, misused Chinese crude drugs are also very common in the past. This phenomenon had caused a lot of confusion and had great influence the clinical efficacy of the treatment. In the past, Professor Hong Yen Hsu, Na Chi, Woei Song Kan and Kung Yin Yen had studied the origins of Chinese crude drugs in Taiwan based on the morphological identification and found that the origins of Ma-Tou-Ling, Pu-Kung-Yin, Tu-Chung, Wang-Pu-Liu-Hsing, Pan-lan-Ken, Niu-Chi, Fang-Chi, Huang-Chi, PienHsiu and Sha Wan-Tzi are different from that of the species used in mainland China. In order to assure the quality and clinical efficacy of the crude drugs, besides the traditional morphological methods, we bad recently combined modem chemical and pharma-cological methods to assess drug quality. Drugs that have been evaluated without effects should be abandoned. The species of those commonly misued crude drugs used in compound formula preparations are also identified Based on the pharmacological results, a suitable species is recommended so as to improve the clinical efficacy of those preparations. In this paper, we like to report our recent studies on Niu Chi(Achyranthis Bidentatae Radix, Cyathulae Radix and Strobilanthis Radix). Fang-Chi(Arstolochiae Fangchi Radix, Stephaniae Tetrandrae Radix and Cocculus Radix) and Huang-Chi(Astragali Radix and Hedysari Radix) using comparative pharmacognosy methods.

• Journal of Periodontal and Implant Science
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• v.40 no.2
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• pp.76-85
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• 2010

Purpose: This study aimed to evaluate the effectiveness of the modified sinus floor elevation technique described hereafter as a "hybrid technique," in 11 patients with severely resorbed posterior maxillae. Methods: Eleven patients who received 22 implants in the maxillary premolar and molar areas by the hybrid technique were enrolled in this study. A slot-shaped osteotomy for access was prepared on the lateral wall along the lower border of the sinus floor. The Schneiderian membrane was fully reflected through the lateral slot. Following drilling with the membrane protected by a periosteal elevator, the bone was grafted. All implants were placed simultaneously with sinus augmentation. The cumulative success rate was calculated and clinical parameters were recorded. Radiographic measurements were performed. Results: All implants were well maintained at last follow up (cumulative success rate=100%). The mean residual bone height, augmented bone height, crown-to-implant ratio, and marginal bone loss were $4.1{\pm}1.64mm$, $8.76{\pm}1.77mm$, $1.21{\pm}0.34mm$, and $0.34{\pm}0.72mm$, respectively. Conclusions: Simultaneous implant placement with sinus augmentation by hybrid technique showed successful clinical results over a 2-year observation period and may be a reliable modality for reconstruction of a severely resorbed posterior maxilla.

• Journal of Periodontal and Implant Science
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• v.39 no.4
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• pp.431-435
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• 2009

Purpose: The purpose of this study is to evaluate the long term clinical and radiographic outcome and stability after transplantation of third molar with complete root formation. Methods: The subjects were 31 teeth (male 17, female 14, aged 22-55, average 39.9 yr old) of 31 patients who visited the department of periodontics and passed more than two years after autotransplantation procedure and still under regular check up. Modified success criteria of Chamberlin and Goerig was applied to determine the success of autotransplantation. Results: Three out of 31 teeth failed and resulted 90.3% of success rate. When compared according to sex, 15 out of 17 teeth had succeeded in male, 13 out of 14 succeeded in female. When compared the success rate according to cause of extraction, tooth loss due to caries and root fracture had all succeeded but 3 out of 24 had failed in tooth loss due to periodontal disease. When compared according to donor teeth, 12 out of 14 maxillary third molars and 16 out of 17 mandibular third molars had succeeded. Conclusions: In long term evaluation over two years, if appropriate surgical procedure and proper case selection is made, autotransplantation of the third molar with complete root formation can be the alternative choice that substitutes prosthetic or implant treatment and it is a functionally acceptable procedure.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.245-248
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• 2008

Recently, much research has been conducted on FRP composite to replace steel. However, the concept of FRP girder filled with concrete has not been fully attempted. This study focuses on the analytical behavior of FRP girders filled with concrete. FRP girders usually have large deflection due to relatively low elastic modulus compared to steel members. However, in the previous experimental investigation on small sized modular beams, it has been verified that the displacement of FRP-girder filled with concrete is reduced and the strength is increased considerably. In this research, analytical investigations have conducted to verify the analytical method by comparing the results with tests. In addition, analyses on large girders assembled with small modules have been carried out to predict the feasibility before tests. The analytical results showed that the assembled FRP girders can be used as substitutes for steel girders.

• Archives of Craniofacial Surgery
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• v.15 no.1
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• pp.14-21
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• 2014

Background: There are several options for replacement of the dermal layer in fullthickness skin defects. In this study, we present the surgical outcomes of reconstruction using acellular dermal substitutes by means of objective and subjective scar assessment tools. Methods: We retrospectively reviewed the medical records of 78 patients who had undergone autologous split-thickness skin graft with or without concomitant acellular dermal matrix (CGDerm or AlloDerm) graft. We examined graft survival rate and evaluated postoperative functional skin values. Individual comparisons were performed between the area of skin graft and the surrounding normal skin. Nine months after surgery, we compared the skin qualities of CGDerm graft group (n=25), AlloDerm graft group (n=8) with skin graft only group (n=23) each other using the objective and subjective measurements. Results: The average of graft survival rate was 93% for CGDerm group, 92% for AlloDerm group and 86% for skin graft only group. Comparing CGDerm grafted skin to the surrounding normal skin, mean elasticity, hydration, and skin barrier values were 87%, 86%, and 82%, respectively. AlloDerm grafted skin values were 84%, 85%, and 84%, respectively. There were no statistical differences between the CGDerm and AlloDerm groups with regard to graft survival rate and skin functional analysis values. However, both groups showed more improvement of skin quality than skin graft only group. Conclusion: The new dermal substitute (CGDerm) demonstrated comparable results with regard to elasticity, humidification, and skin barrier effect when compared with conventional dermal substitute (AlloDerm).