• 한국과학교육학회지
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• 제25권1호
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• pp.16-25
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• 2005

Minute papers are brief papers written at the end of a lecture in response to one or two questions posed by the instructor. The answers are discussed briefly at the beginning of the next lecture. We used minute papers to follow students' understanding and response to lecture demonstrations in an introductory general chemistry course. An analysis of these minute papers suggest that the following characteristics are important, when using demonstrations as teaching aids. 1) The purpose of a demonstration should be stated as explicitly as possible. 2) Instructors should be explicit about what is happening and what students should be looking for. 3) Demonstrations should be kept as simple as possible, perhaps illustrating one concept. Finally, we note that students believe that the visual component of demonstrations enhances their comprehension of chemistry concepts.

• 한국임상수의학회지
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• 제22권3호
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• pp.259-263
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• 2005

To compare cardiopulmonary effects and recovery between total intravenous anesthesia (TIVA) with propofol (PRO group, n=5) and volatile induction/maintenance anesthesia (VIMA) with isoflurane (ISO group, n=5), we investigated changes of heart rate, $SpO_2$, arterial pressure, rectal temperature and respiratory rate during 60 minute anesthesia and 40 minute recovery period in beagle dogs, and investigated recovery (extubation, head lift, sternal position and righting) after 60 minute anesthesia. Rectal temperature was significantly low in ISO group (p<0.05) from 10 to 100 minute. Heart rate was significantly low in ISO group (p<0.05) at 40, 50, 60 minute. Respiratory rate was significantly low in PRO group (p<0.05) at induction and 70 minute. $SpO_2$ tendency was similar. Systolic arterial pressure (SAP) was significantly low in ISO group (p<0.05) at induction and during anesthesia. Recovery was similar in two groups. We concluded that TIVA with propofol is useful in stabilizing rectal temperature and arterial pressure during anesthesia and provide fast and stable recovery.

• 한국임상수의학회지
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• 제14권2호
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• pp.208-214
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• 1997

The objective of this study was (a) to examine the change of bloodchemistry and (b) to investigate the secretion trend of endocrinological substance in a dog model after laser-beam radiation at different level of frequency (250 Hz, 2,000 Hz, 5,000 Hz and 8,000 Hz). The experimental groups were divided into four groups were divided into four groups on the basis of the level of frequency radiated and stimulated for five minutes. Before stimulation and after a lapse of time (10-minute, 30-minute and 60-minute) all dogs were checked the following parameters; cortisol, ACTH, RBC, hemoglobin, hematocrit, WBC, Ca, P, ALT, AST and creatinine. The results were as follow: ten minutes after stimulation, cortisol level of 250 Hz group, 2,000 Hz group, 5,000 Hz group and 8,000 Hz group was increased 18.8%, 20.5%, 23.2% and 309%, respectively. Ten minutes after stimulation, ACTH level of 250 Hz group, 2,000 Hz group, 5,000 Hz group and 8,000 Hz group was increased 26.7%, 26.6%, 30.5% and 29.5%, respectively. It began to decrease and at 30-minute after stimulation resturned to pre-stimulation level at 60-minute after stimulation. In blood examination RBC, hemaoglobin, hematocrit and WBC level showed slight increase and decrease and returned to pre-stimulation level at 60-minute after radiation. In bloodchemical examination serum calcium, inorganic phosphorus, ALT, AST and creatinine level were within normal physiological ranges.

• 대한방사선기술학회지:방사선기술과학
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• 제38권2호
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• pp.115-120
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• 2015

Gadoxetic acid (GA) 조영증강 자기공명(MR) 영상에서 일반적으로 많이 이용되는 숙임각(flip angle, FA) $11^{\circ}$와 비교하여 FA $30^{\circ}$를 이용한 3분, 10분 및 15분 영상에서 국소성 간 병변 검출 차이를 알아보고자 하였다. 대상 및 방법 : 3.0T MR 기기로 GA 조영증강지연기 MR영상을 시행 받은 69명의 환자를 대상으로 하였다. 대상 환자는 간세포암 23명과 전이암 12명으로 총 35명(남성 23, 여성12, 평균연령 60.4세)이었다. GA 주입 후 3분, 10분, 15분의 영상에서 각각 FA $11^{\circ}$와 $30^{\circ}$ 영상을 획득하였다. 각각의 영상에서 정량적평가와 정성적평가를 한 뒤 독립표본 T검정을 이용하여 통계적 분석을 하였다. 정량적 평가와 정성적 평가 모두 조영제 주입 후 3분과 10분 영상에서 FA $30^{\circ}$ 영상이 FA $11^{\circ}$ 영상보다 약간 우수하였으나 통계적 유의성은 없었다. 그러나 15분 영상에서는 FA $30^{\circ}$ 영상이 FA $11^{\circ}$ 영상보다 통계적으로 유의하게 우수하였다(p<0.05). GA 조영증강 후 15분 MR영상에서 FA $30^{\circ}$ 영상은 기존의 FA $11^{\circ}$ 영상보다 간 병변을 민감하게 검출해낼 수 있다.

• 한국도서관정보학회지
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• 제48권3호
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• pp.45-61
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• 2017

본 연구의 목적은 DDC가 당시 도서관 장서의 급속한 증가 문제를 해결하기 위해 도서관 최초로 상관식 배가법을 도입하고 세분화된 분류체계를 적용한 것이 도서관계에 어떤 영향을 미쳤는지 분석하는데 있다. 이를 위해 DDC가 상관식 배가법을 도입하고, 분류체계를 세분화하여, 도서관과 타 분류법에 미친 영향 등을 비교 분석하였다. 분석 결과 첫째, DDC는 이전에는 존재하지 않았던 상관식 배가법이라는 혁신적인 방법을 적용하여, 세분화된 분류체계를 도입하면서 당시 도서관이 처해있던 급속한 장서 증가 문제를 해결하였다. 둘째, 세부적인 분류를 위해 형식 구분을 분류기준으로 적용하여 실질적으로 도서관의 도서 분류에 도움을 주었다. 셋째, 분류체계에 십진법을 도입함으로써 분류체계의 무한정 세분화가 가능하여, 경제성과 실용성을 획득하였다. 넷째, 전개분류법이나 주제분류법을 비롯한 현대 도서관 분류법 발전에 큰 영향을 미쳤다. 이처럼 상관식 배가법을 적용하고 세분화된 분류체계를 가진 DDC는 시대적 요구에 적합한 분류법이었고, 개별 도서관에서 실용적으로 사용할 수 있는 분류법이었다.

• Clinical and Experimental Reproductive Medicine
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• 제26권2호
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• pp.219-223
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• 1999

Ovarian development of the vitrified neonatal ovaries after orthotopical transplantation into the ovariectomized adult recipient mouse were observed. Ovaries were collected from the neonatal females on day of birth and grouped for fresh, vitrification for 1-minute, and 3-minute. Vitrified and thawed neonatal ovaries were orthotopically transplanted into ovarian bursa of the adult mice from which endogenous ovaries have removed just prior to the transplantation (1 minute: n=25; 3 minutes n=23). Fresh ovarian tissue transplanted (n=25) mice were included as control groups. Returning of the estrus cycles and the survival and development of the transplanted ovaries were evaluated. Intact ovaries from neonatal, and four weeks old mice were used for comparison of the ovarian development as in vivo-developed control. From 2 weeks after transplantation, 64%, 36%, and 75% of the transplanted mice showed return of the estrus cycles in fresh, 1-minute, and 3-minute groups, respectively. Four weeks after transplantation, all mice were sacrificed and ovarian tissues were recovered for histological analysis. 57.1%, 33.3%, and 64.7% mice in fresh, 1-minute, and 3-minute groups, respectively, had survived ovaries with follicles at various stages of growth from primordial to preovulatory follicles. Corpus lutea were also observed. Results of the present study suggest that 1) normal folliculogenesis has initiated in vivo after vitrification, and 2) the vitrification may be used as a preservation method for ovarian tissues for establishment of ovarian tissue bank.

• Journal of Periodontal and Implant Science
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• 제30권4호
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• pp.821-836
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• 2000

The Peri-implantitis causes inflammation of periodontal tissue and bone loss. It contaminates surface of implants. Therefore, guided bone regeneration has been used for the treatment of this disease. For the reosseointegration of the exposed surface, various mechanical and chemical methods have been used for cleaning and detoxication of implant surface. Among these methods, air-powder abrasive and oversaturated citrate are known to be most effective. However, these treatments may deform implant surface. In this research, changes of surface roughness they were examined. 10 experimental machined titanium cylinder models were fabricated to be used for control groups. Each of them was air powder abraded for 1 minute and they were named group 1. And then, group 1 were burnished with cotton pellets soaked with citrate for 30 seconds(Group 2), 1 minute(Group 3), 3 minutes(Group 4), and 5 minutes(Group 5) burnishing were applied for grouping respectively. Each group were examined with SPM, and their surface roughness were measured and analyzed. 1. Surface roughness of titanium decreased when it was air-powder abraded for 1 minute. It was statistically significant. 2. When Air-powder abraded titanium were treated with citrate for 3 minutes, Their surface roughness was the lowest. Titanium treated for 1 minute was the second lowest and 30 seconds was the third and titanium burnished for 5 minutes was the highest. 3. Surface roughness of titanium which was treated with citrate was decreased till 3 minutes, which was statistically significant. There was no statistical significance from 30 seconds to 1 minute and from 1 minute to 3 minutes, and there was statistical significance from 30 seconds to 3 minutes. 4. Oxide layer was formed when titanium is exposed to air, and it was removed when air-powder abraded. It was made when treated with citrate. It is thought that citrate treatment is necessary after the air-powder abrasion, and 1 minute is clinically and qualitatively adequate for burnishing time of citrate.

• Journal of Ceramic Processing Research
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• 제20권6호
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• pp.589-596
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• 2019

Pigments with minute particle sizes, such as carbon black (CB) and pigment red 48:2 (P.R.48:2), are the most important types of pigment and have been widely used in many industrial applications. However, minute particles have large surface areas, high oil absorption and low surface energy. They therefore tend to be repellent to the vehicle and lose stability, resulting in significant increases in viscosity or reaggregation in the vehicle. Therefore, finding the best way to improve the dispersion properties of minute particle size pigments presents a major technical challenge. In this study, minute particle types of CB and P.R.48:2 were treated with nitrogen gas plasma generated via radio frequency-plasma enhanced chemical vapor deposition (RF-PECVD) to increase the dispersion properties of minute particles in deionized (DI) water. The morphologies and particle sizes of untreated and plasma treated particles were evaluated using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The average distributions of particle size were measured using a laser particle sizer. Fourier transform infrared spectroscopy was carried out on the samples to identify changes in molecular interactions during plasma processing. The results of our analysis indicate that N2 plasma treatment is an effective method for improving the dispersibility of minute particles of pigment in DI water.

• International Journal of Internet, Broadcasting and Communication
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• 제14권4호
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• pp.163-172
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• 2022

The purpose of this study is to investigate the changes in the number of repetitions and the repetition rate according to the exercise mode when performing 65%1RM resistance exercise at the 1-minute rest interval and the 3-minute rest interval. Sixteen healthy male subjects were treated with Bench press and Biceps curl of 65%1RM intensity at 1 and 3 minute rest intervals. The number of repetitions for each set of 1 minute rest interval showed a significant decrease from 1set to 5set in bench press. biceps curl showed a significant decrease from 1set to 4set. The repetition rate according to the exercise mode with a 1-minute rest interval showed a significant difference from 2sets to 4sets. In the repetition rate for each set, bench press showed a significant decrease from 1set to 5set. biceps curl showed a significant decrease from set 1 to set 4. The number of repetitions according to the exercise mode with a 3-minute rest interval showed a significant difference from 2sets to 5sets. In the number of repetitions for each set, bench press showed a significant decrease from 1set to 5set. biceps curl showed a significant decrease from 1set to 4set. The repetition rate according to the exercise mode with a 3-minute rest interval showed a significant difference from 2sets to 5sets. In the repetition rate for each set, bench press showed a significant decrease from 1 set to 5 sets. biceps curl showed a significant decrease from 1set to 4set. In summary, the decrease in the number of repetitions according to the set progression in the resistance exercise of the endurance depends on the exercise mode, and the increase of the rest interval or the decrease of the weight-intensity should be considered when aiming for more exercise.

• 안전기술
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• 44호
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• pp.43-43
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• 2001