• Journal of The Korean Association of Information Education
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• v.21 no.4
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• pp.451-462
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• 2017

This study selected 3D printing that is highly likely to be adopted in schools. This research was conducted in two stages: 1) proposing the learning activity framework for utilizing 3D printing in education, and 2) exploring the potential of integrating 3D printing in the school field. The '3D printing learning activity framework' proposed in this study includes four phases that are categorized according to the complexity of problem-solving processes and collaborative interaction: Step 1 as production through replication, Phase 2 as means of imaginary expression, Phase 3 as near problem-solving, and Phase 4 as expanded problem-solving. Next, we conducted the field study with 23 students in the 6th grade math class where they learned the various solid shapes and volumes through 3D printing-integrated activities. The lesson was considered as Phase 1, which is the production through replication. Overall, the results showed that the participants had positive perceptions about the efficacy of 3D printing activities, the quality of learning experience, and satisfaction. On the other hand, it was found that the usability of 3D printers and CAD program needs further improvement The contribution of this study can be found in the learning activity framework that can guide 3D printing activity design in school, and in the exploration of enhancing the connection between 3D printing activities and curricular relevance beyond simple interest toward a novel technology.

• Journal of Dental Rehabilitation and Applied Science
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• v.36 no.1
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• pp.41-47
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• 2020

Purpose: The purpose of this study was to evaluate the flexural strength and reliability of highly translucent colored zirconia for all ceramic restoration. Materials and Methods: Bar-shaped specimens (25 × 4 × 2.5 mm) were prepared from highly translucent monolithic zirconia. Three experimental groups were set up according to color (shade A0, A1, and A3). For each group, 20 specimens were prepared. Flexural strength was determined using a 3-point flexural test and results were analyzed with one-way ANOVA test. Weibull statistical analysis provided 2 parameter estimates: Weibull modulus and characteristic strength. X-ray diffraction (XRD) analysis was performed. Results: There was statistically significant difference between uncolored (Shade A0) and colored (shade A1 and A3) (P < 0.05), but there was no difference between colored groups (P > 0.05). The uncolored group had higher reliability compared with colored study groups. On x-ray diffraction analysis of each group, typical peaks of tetragonal phase appeared in all groups. Conclusion: Within the limitations of this in vitro study, coloring highly translucent zirconia had significant effect on flexural strength and reliability. Therefore, clinicians should be careful when using highly translucent colored zirconia to prevent breakage of veneering ceramic and enhance aesthetics.

• Korean Journal of Clinical Pharmacy
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• v.15 no.1
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• pp.41-45
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• 2005

심바스타틴은 cholesterol 생합성 과정에서 속도 조절 효소인 HMG-CoA reductase의 강력한 상경적 길항약으로서 고지혈증 치료에 널리 쓰이는 약물이다. 심바스타틴 제제인 MSD 사의 조코 20 mg정을 대조약으로 하여 시험약인 유영 제약의 엘바스타 20mg정의 생물학적 동등성 평가를 하기 위해 22명의 건강한 지원자를 모집하였다. 지원자를 두 군으로 나누어 2정씩 투여하였고 $2{\times}2$ 교차시험을 실시하였다. 심바스타틴의 혈장 중의 농도를 정량하기 위하여 발리데이션된 LC/MS/MS를 사용하였다. 채혈 시간은 투약 전 및 투약 후 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 10, 12 시간에 걸쳐 총 12시점에 걸쳐 시행하였다. 생물학적 동등성을 판정하기 위한 파라미터로 12시간까지의 혈장 중 농도곡선 하 면적 ($AUC_{12hr}$)과 최고 혈중 농도($C_{max}$)를 사용하였다. 12시간 까지의 혈중 농도 곡선 하 면적의 기하 평균은 $17.30ng{\cdot}ml/hr$(시험약)과 $17.35ng{\cdot}ml/hr$(대조약)으로 나타났다. 최고 혈중 농도의 경우 각 각 5.08 ng/ml(시험약)과 5.20 ng/ml(대조약)으로 관찰 되었다. $AUC_{12hr}$의 경우 로그변환한 평균치 차의 $90{\%}$ 신뢰구간이 log0.8510 - log1.1694이었고, $C_{max}$의 경우 log0.8176 - log1.1649로 계산되어 두 항목 모두 log0.8-log1.25이어야 한다는 식품의약품 안전청과 FDA의 기준을 모두 만족시켰다. 이상의 결과를 종합하면 시험약 엘바스타 정 20mg은 대조약 조코정 20 mg에 대하여 생물학적 동등한 것으로 판정되었다.트리머 전기비저항 탐사를 수행하였다. 이를 통해 하저에 케이블을 설치하는 방식에 비해 매우 신속하고 경제적으로 하저에 분포하는 이상대의 분포범위와 발달방향을 규명할 수 있었다.대에 대해 가장 효과적이다. 모델과 현장 적용 결과들을 통해 GRM SSM 방법을 이용하여 불규칙한 굴절면을 가진 지층들에 대해 좀 더 신뢰할 수 있는 정밀한 탄성파 속도를 산출할 수 있음을 보여주고 있다.별한 주의를 기울여야 한다.EX>$\alpha/\beta$=10인 경우 $62.0\~121.9\;Gy_{10}$ (중앙값: $93.0\;Gy_{10}$)의 분포를, ${\alpha/\beta}=3$인 경우 $93.6\~187.3\;Gy_3$ (중앙값=$137.6\;Gy_3$ )의 분포를 보였다. MD-BED $Gy_3$는 직장합병증 발생과의 관계는 통계적으로 유의하였고, 방광합병증과는 유의하지 않았다. 직장합병증과의 연관성은 MD-BED $Gy_3$보다 개별 환자의 직장전벽 총 선량 BED값인 R-BED $Gy_3$가 훨씬 더 높았다. 요도카테터 풍선의 후방지점이 대변하는 방광의 총 선량 BED값인 V-BED $Gy_3$도 방광합병증과 경향성 테스트에서 통계적 유의성을 보였다. 하지만, 어떠한 방사선선량도 골반제어율과 의미 있는 상관관계를 보이지 않았다. 본 기관에서 주치의의 선호도에 따라 강내근접치료가 외부방사선치료의 중간에 시행되는 형태인 샌드위치기법과 외부방사선치료 후반부에 시행되는 순차적 기법으로 구분하였을 때, 두 방식간 치료성적 및 합병증의 차이는 없었다. 총 치료기간에 대한 분석에서는 치료기간이 길어질수록 재발 위험이 커지는 경향을 보였으나, 나이 및 병기, 종양의 크기, MD-BED $Gy_{10}$

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.11
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• pp.1385-1390
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• 2007

Anticarcinogenic-active compound was isolated and purified from Angelica gigas Nakai. The compound was identified as decursin ($C_{19}H_{20}O_5$; molecular weight 328) by mass, IR spectrophotometry $^1H-NMR$ and $^{13}C-NMR$. The proliferation decreased in a dose dependant fashion in the MCF-7 cells treated with decursin for 24 hours over the concentration of $20{\mu}g/mL$. The $IC_{50}$ value of the decursin treatment for 24 hours were 31.04, 33.60, 27,24, $20.45{\mu}g/mL$ in the SW480, 293, HepG2 and MCF-7 cells, respectively, The growth inhibitory effect was stronger in the MCF-7 cells compared to other cells including 293 of human normal cells. The chromatin condensation, apoptotic body formation and DNA fragmentation were examined in the cells treated with decursin. These results suggest that decursin from Angelica gigas Nakai inhibited the growth through apoptosis in MCF-7 cells.

• Journal of Science Education
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• v.36 no.2
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• pp.279-292
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• 2012

The purpose of this study is to find the concept of life, the categories of living things and the systems of categorizing them contained in Buddhism, a sort of metaphysical philosophy. For this, monks who devotes themselves to Buddhism were interviewed, and the differences of the definition of life, the categorizing of living creatures and categorizing systems between biology and other subject teachers and students who are Buddhist and ones who are not were inquired. The result shows that in Buddhism, they use 'being' and 'sentience being' as the terms for creatures and they believe creatures are not individual ones but one collective existence connected with each other, which is very different from the biological definition of creatures. Buddhist include metaphysical beings in categories of living things rather than plants. Buddhist criteria for categorizing things which have life, that is living beings, are how they are born, whether they have a certain form and, lastly, whether they are conscious or not. Through this research results we could expect to identify the misconceptions about concept of life and the categories of living things.

• Archives of design research
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• v.11 no.2
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• pp.203-213
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• 1998

The forthcoming twenty-first century is at the mercy of information and culture. A quality of humanlife is under the control of a cultural level. A nation's creative culture and a cultural level represent all things about the nation; and a national image, as a whole result of culture, is enormously influential. This new era of culturalism gives us a significant responsibility for getting ready for the late industrial society by practically harmonizing rationality of modem culture with conception of traditional culture. Industrializing culture and culturalizing industry will be the most important strategy for existence in these days of borderless international competitiveness. Cultural products which is containing a nation's own culture can not only enhance the national image, but also become high value-added industry. While general products are developed for the purpose of convenient and practical use, cultural products are created with the intention of informing international society about a nation or a region. In order to confront with a global market system and a change of cultural environment, it is necessary to create a proper design with cultural inheritance for modem likes and senses, to produce the design on a commercial scale, and to strengthen its competitiveness on international markets. In order that a commodity is born, distributed throughout markets, and delivered to a final consumer, it is essential to understand complicated process such as development, distribution and marketing of products and to systematize each part. Although we should not neglect any part, a political and systemical plan or a distributional and marketing idea will be beside the point in this article. This article presents importance of traditional patterns as a Korean cultural image, and it shows the process of designing and developing products in order for traditional patterns to be utilized for products effectively. I expect that concrete activation and systematization for those works can be carried out successively.

• Korean Journal of Plant Tissue Culture
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• v.25 no.1
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• pp.69-74
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• 1998

The somatic embryos of Daucus carota L. cv. Hongshim developed in MS basal medium far 4 weeks had varied number of cotyledons. Palisade and spongy parenchyma of cotyledon were not clearly discriminated in all seedlings developed from the embryos. No independent existence of collateral vascular bundle was observed in all seedlings with various types of cotyledon ; instead, vascular bundles were either interconnected or partially connected with one another. Most of the cotyledonary bases on hypocotyl showed short cylinder structure which encircle plumule. The vascular tissues of cotyledonary bases and nodes of seedlings with jar-shaped or 1 cotyledon were connected in ring forms, showing the pattern of ectophloic shiphonostele, and similar ring form structure was also found in the vascular arrangement of 5 cotyledon seedlings. The vascular bundles of seedlings with 2, 3 and 4 cotyledons in many cases had independently arranged within the cotyledonary bases and nodes, showing the pattern of eustele. In hypocotyl, tetrarch or hexarch xylems prevailed in seedlings with jar-shaped cotyledon or 1 and 5 cotyledon; tetrarch xylems prevailed in 2 cotyledon seedlings; and triarch xylems prevailed in 3 cotyledon seedlings. In most of seedlings, cortex vascular bundles were dispensed in the region from cotyledonary node to hypocotyl, but double vascular bundles were also observed occasionally. In roots, diarch xylems were observed in most of seedlings with 2 cotyledons, triarch xylems in half of seedlings with 3 cotyledons, and diarch xylems in most of the remaining seedlings with the occasional occurrences of tetrarch xylems.

• Korean Journal of Poultry Science
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• v.38 no.3
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• pp.239-245
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• 2011

Pigments in the diet affect yolk colors. Due to variations in both the bioavailability of pigments in chickens and their amounts occurring in the feed ingredients, concern about egg quality arises in terms of yolk color. In this study, the effects of pigments, produced through cell culture in the laboratory, on yolk colors were determined for 4 weeks in laying hens receiving one of the 6 dietary treatments: control diets containing 1) no synthetic pigments (CON); 2) canthaxanthin (4 ppm) purchased from BASF (BASF); 3) cultured cells so that the diet had canthaxanthin at 4 ppm (CX); 4) cultured cells so that the diet had lycopene at 30 ppm (LP); 5) canthaxanthin (4 ppm) that was purified from cultured cells (SPCX); or 6) lycopene (30 ppm) that was purified from cultured cells. Relation between deposition of pigments into yolks and egg production was also tested. Yolk color of eggs from chickens fed dietary CX was significantly enhanced, which was slightly but significantly below that of BASF. Results from other treatments were lower than those of CX. Deposit rates of pigments into yolks were: BASF > CX > SPCX > LP > SPLP. The amounts of pigments, with the exception of SPLP, in feed were not changed during the storage for 4 weeks at $25^{\circ}C$. Egg production rates varied among treatments during the initial phase of the study but became relatively uniform at the later stage, except for CON and LP groups. The results of the present study indicate that the deposition of pigments into yolks is independent of egg production.

• Korean Journal of Poultry Science
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• v.38 no.3
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• pp.181-189
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• 2011

A 5-month (May to November in 2009) monitoring program for five viral pathogens in litter, such as avian influenza virus A (AIV), infectious bronchitis virus (IBV), infectious bursal disease virus (IBDV), fowl adenovirus (FAdV), and chicken infectious anemia virus (CIAV) was conducted in 62 flocks at 31 broiler farms (two flocks in each farm) in Korea in 2009. Viral pathogens were examined twice (before and at the end of the rearing period) at 31 broiler farms, and included fresh litter (n = 16) and recycled litter (n = 15) farms. Thirty-seven viruses (14 IBVs, 2 IBDVs, 9 FAdVs, and 12 CIAVs) were isolated from 75% (12/16) and 73% (11/15) of fresh litter and reused litter farms during the period, respectively, indicating no difference in viral contamination rate between farms using new and reused litter. Of these isolates, three (two CIAVs and one IBDV) were isolated from recycled litter samples collected before the rearing period at three broiler farms, whereas the others (n=34) were isolated from fresh and recycled litter samples collected at the end of the rearing period. When the performances, involving viability, body weight, and feed conversion ratio, were compared, no significant differences were found between farms using fresh and recycled litter during the period.

• Journal of the Korean Arthroscopy Society
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• v.9 no.2
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• pp.186-193
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• 2005

Purpose: To determine whether it is possible to differentiate between ALPSA(anterior labroligamentous periosteal sleeve avulsion) lesion and Bankart lesion using arthroscopic findings and to investigate the clinical significance of ALPSA lesion. Materials and Methods: This study was performed on 66 cases that underwent arthroscopic Bankart repair for the anterior instability of the shoulder. By the readings of MRI, there were 56 cases(85%) of Bankart lesion and ten cases(15%) of ALPSA lesion. Arthroscopic findings of Each cases were classified and their average follow-up period was 22 months. Results: It was observed that ALPSA lesions developed in younger age groups than Bankart lesions. Under the arthroscope, ALPSA lesions showed various forms, especially there were five cases of severe inferomedial displacements. Within Bankart lesion, 21 cases were observed to be severely displaced and from the arthroscopic findings, it was difficult to distinguish the difference of Bankart lesion cases displaced inferomedially from the neck of scapula without severe lateral displacements and ALPSA lesion. Regarding the recurrence, there were no redislocation but apprehension shows in two cases(20%) with severe inferomedial displacement in ALPSA group. In Bankart lesion, there were four recurrent cases(7.1%); one of redislocation; one case of subluxation; two of apprehension. Conclusion: It was difficult to differentiate Bankart lesion and ALPSA lesion with severe inferomedial displacement and severely displaced ALPSA lesion showed high rate of recurrence. Thus, complete detachment of ALPSA lesion should be performed more carefully to reduce the recurrence rate.