• Restorative Dentistry and Endodontics
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• 제15권1호
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• pp.120-128
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• 1990

The purpose of this study was to examine the effect of surface treatment on the flexural strength of glass ionomer cement with time elapsed. Glass ionomer cement (Fuji ionomer type II, (GC Co.) was used as experimental materials. Glass ionomer cement was placed in a beam-shaped teflon mold (3mm ${\times}$ 3mm ${\times}$ 25mm) that was rest on a glass plate. Another flat glass was placed on the top of the mold with pressure. After the cement was set, the specimens were divided into three groups and thirty two specimens in each group were surface-treated as follows: No treatment group: Specimens were no surface-treated and stored at $35.6^{\circ}C$ in distilled water. Fuji varnish application (FA) group: Specimens were surface-treated with Fuji varnish (GC Co.) and stored at $35.6^{\circ}C$ in distilled water. Vaseline storage (VS) group: Specimens were no surface-treated and stored at $35.6^{\circ}C$ in vaseline. The flexural strength was measured after I day, 1 week, 2 weeks, 4 weeks from the start of mixing using Instron Universal Testing Instruments. Results were as follows: 1. After 4 weeks, vaseline storage group exhibited the maximum flexural strength (p <0.0005). 2. The flexural strengths in no treatment group were slightly increased with time elapsed, but its difference was not significant, statistically. 3. The flexural strengths in Fuji varnish application group were increased with time elapsed (p <0.05). 4. The flexural strengths in Fuji varnish application group and vaseline storage group were greater than that in no treatment group (p <0.0005).

• Journal of Multimedia Information System
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• 제9권2호
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• pp.113-120
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• 2022

Mongolian folk songs are inspired by Mongolian labor songs and are classified into long and short songs. Mongolian long songs have ancient origins, are rich in legends, and are a great source of folklore. So it was inscribed by UNESCO in 2008. Mongolian written literature is formed under the direct influence of oral literature. Mongolian long song has 3 classes: ayzam, suman, and besreg by their lyrics and structure. In ayzam long song, the world perfectly embodies the philosophical nature of world phenomena and the nature of human life. Suman long song has a wide range of topics such as the common way of life, respect for ancestors, respect for fathers, respect for mountains and water, livestock and animal husbandry, as well as the history of Mongolia. Besreg long songs are dominated by commanded and trained characters. In this paper, we proposed a method to classify their 3 types of long songs using machine learning, based on their lyrics structures without semantic information. We collected lyrics of over 80 long songs and extracted 11 features from every single song. The features are the name of a song, number of the verse, number of lines, number of words, general value, double value, elapsed time of verse, elapsed time of 5 words, and the longest elapsed time of 1 word, full text, and type label. In experimental results, our proposed features show on average 78% recognition rates in function type machine learning methods, to classify the ayzam, suman, and besreg classes.

• 한국응급구조학회지
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• 제17권1호
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• pp.9-19
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• 2013

Purpose : The purpose of this study was to investigate the variation of elapsed time in the cardiopulmonary resuscitation (CPR) quality and the fatigue in continuous CPR by single rescuer. This study will provide basic data about the time for the alternation of the CPR providers. Methods : The volunteer students having healthcare provider certification were recruited from the department of emergency medical service. The students performed 30:2 CPR for 20 minutes, and the data were recorded and analyzed. Metrics were based on the 2010 American Heart Association (AHA) Guidelines, and the CPR continued without any feedback. Results : Among the indicators of CPR, the accuracy and the depth of chest compressions decreased after about 5.3 minutes, and the rate increased approximately after 6.8 minutes. Changes in clinical indicators appeared, and fatigue increased after about 3 minutes. According to the increase in fatigue level, the changes in the CPR indicators and clinical indicators showed up, and these results proved to be statistically significant. However, there were no associations among the time, fatigue, and gender. Conclusion : Even though the times of changes in the indicators appeared differently, the times of changes in fatigue and CPR quality were able to be confirmed.

• 한국해안·해양공학회논문집
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• 제32권3호
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• pp.147-160
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• 2020

추계학적 WP을 이용하여 불확실성을 고려하면서 항만 구조물의 실시간에 따른 피해와 파괴확률 그리고 잔류수명을 해석할 수 있는 모형을 수립하였다. 과거부터 현재까지의 피해상태와 미래에 발생될 피해 진행 과정에 포함되는 불확실성을 고려할 수 있는 추계학적 확률모형이다. 피해경로를 추적할 수 있으며 누적피해의 밀도함수도 산정하여 파괴확률을 추정할 수 있다. 또한 구조물의 잔류수명에 대한 밀도함수도 구할 수 있다. 최소자승법과 최우도법을 이용하여 모형의 파라미터를 추정할 수 있는 방법도 제시하였다. 검증을 위해 시간의 진행에 따른 누적피해와 잔류수명에 대한 밀도함수를 산정하고 해석하였는데 이론적인 결과가 MCS 기법의 수치적인 결과와 매우 잘 일치하였다. 또한 내구수명이나 잔류수명에 대한 밀도함수의 거동과 MTTF와 MRL이 정량적으로 잘 일치하였다. 한편 본 연구에 수립된 모형을 경사제에 적용하기 위하여 피복재 피해에 대한 수리모형 실험자료를 활용하여 모형의 파라미터들을 추정하였다. 시간의 진행에 따른 피복재 누적피해의 밀도함수와 파괴확률을 산정하였는데 MCS의 결과와 이론적인 결과가 매우 잘 일치하였다. 경과시간이 클수록 밀도함수가 우측으로 이동하면서 불확실성이 커지면서 파괴확률이 급격하게 증가하였다. 또한 재령에 따른 잔류수명의 거동특성을 해석하였는데, 잔류수명의 분포함수에서 좌측보다는 우측 꼬리 부분이 길게 형성되어 MRL이 급격하게 감소하는 경향을 보였다. 이는 경사제 피복재의 피해가 완만하게 증가하는 현상을 반영한 것으로 판단된다. 특히 재령과 내구수명 그리고 잔류수명의 관계를 해석하였는데, 재령이 오래될수록 재령과 MRL의 합이 MTTF와 큰 차이를 보이고 있다. 이는 재령이 증가하면 잔류수명의 평균인 MRL이 불확실성에 의하여 급격히 감소하기 때문이다.

• 한국초지조사료학회지
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• 제25권1호
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• pp.43-50
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• 2005

The purpose of this study is to discuss the ways to consistently feed high quality corn silage(CS). This study evaluated the effect of the corn silage, after a certain time has elapsed, on the chemical composition and fermentation characteristics after feedout during the winter feeding period of the CS. Six samples of CS from four dairy farms(E1, E2, E3, and L1 ) were taken in order to feed the milking cows over a winter feeding Period from November of 2002 until February of the following year, 2003(six samples were taken at the fellowing dates in the following order: sample one was taken on the 23rd Nov. 2002, sample two on the 5th of Dec. 2002, 3rd sample on the 23rd of Dec. 2002, 4th sample on the 7th of Jan. 2003, 5th sample on the 22nd of Jan. 2003, and the 6th sampling was carried out on the 6th of Feb. 2003) at the three sampling sites after the opening of the trench silos at intervals of 15 days. In the dry matter contents of CS, there wasn't any specific tendency according to the elapsed time in the range of 21.3~$27.3\%$ at all low dairy farm(E1, E2, E3, and L1). And the average dry matter contents were 24.1, 25.9, 23.6, and $20.4\%$. Considering the Proper amount of the dry matter of CS during the ripen yellow stage, the appropriate moisture content was $33\%$ (NRC, 1989), and these dry matter contents were all low. A consistent tendency was not found in the contents of CS. The average of CP contents were 10.2, 8.0, 8.5, and $9.8\%$ at the E1, E2, E3, and L1 farms, and there were significant differences. The TDN contents of CS were not different among forms according to the time elapsed. The pH, according to the time elapsed after opening of the CS, there were no differences at each of E1, E2, E3, md L1 farms. Average pH were 3.5, 3.9, 3.6, and 4.1, md all of them were in normal range. In the lactic acid contents of CS, a consistent tendency was not found among four farms. But according to the time elapsed. there was a goat difference from 1.13~$7.8\%$ The acetate, propionate, and butyrate contents of CS were very low. In this study, there was no significant difference in the CS's chemical composition and fermentation characteristics according to the elapsed time at all four dairy farms. Considering the proper dry matter contents of CS during the ripen yellow stage, the appropriate dry matter content was $33\%$, and dry matter contents of few farms were all low. To enhance the quality of corn silage should be ensiled com at proper dry matter content range from 28 to $35\%$ Therefore, content of the corn plant should be always be closely monitored prior to beginning harvest.

• The Korean Journal of Physiology
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• 제1권2호
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• pp.157-168
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• 1967

The entry of antipyrine and urea from the peritoneal cavity of rabbit into organ tissue and blood plasma was studied. Two hundred mg of antipyrine plus 300 mg of urea in 10 ml Ringer's solution was injected into the peritoneal cavity of anesthetized rabbit. The injection was made from above of a rabbit kept tying right side down and it enabled part of the abdominal organs (liver, intestine, kidney) was immersed in the injected solution and kept high concentration gradient throughout the experimental period. The remaining part of the organs was revered only by a thin film of the test solution. Subsequently, in this part of the organs the concentration gradient of the diffusible substances during entry was presumed to decrease as time elapsed. Four pieces of the liver tissue were taken namely, the right superficial, right deep, left superficial and left deep portions. Two were taken from the small intestine, one from the portion which was immersed in. the fluid and the other from that above the fluid mass. Both kidneys were separately analyzed. As a remote organ the gastrocnemius muscle was taken from the right leg of the animal. The intervals which were the time periods elapsed after injections were 5,7,10,15 or 30 minutes. At each point 5 animals were sacrificed and the concentrations of the test substances in the tissue water were measured. The results obtained were as follows. 1. In the liver the right portion which was immersed in the fluid showed higher concentration if the test substances than the left portion and the superficial region exceeded the deep region. The concentrations diminished as the time elapsed after infusion, particulary in the case of antipyrine, suggesting circulatory removal of the substances. In urea such decreasing tendency of the concentration was not obvious, and suggested slower removal rate of it as compared with that of antipyrine. 2. In the small intestine there was no regional difference in the concentration of the test substances. Because of the intestinal motility different portions of the intestine were seemed to have bathed in the fluid of the same concentration. In general the concentrations in the intestinal wall exceeded those of the liver, suggesting a slower removal rate than in the latter. 3. In the kidney the accumulation of the endogenous urea was predominant, and the accumulating mechanism in the renal tissue went on during the period of the experiment. Therefore it revealed increasing tendencies as the time elapsed. The penetration of the test substances in this organ from the peritoneal cavity seemed to be slower than in other abdominal organs, namely liver or small intestine. Part of the test substances in the kidney were obviously brought by the blood stream. 4. Rapid exponential decay of the concentration of antipyrine and of the osmolality of the peritoneal fluid was attributed to the extensive removal through the whole dimension of the peritoneal surface, and the remote organ such as the gastrocnemius muscle attained a fairly close value to that of the abdominal organs in less than 30 minutes. The factors which related to the absorption rate were discussed. They were the concentration gradient, permeability and the regional perfusion rate.

• 자원환경지질
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• 제54권4호
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• pp.457-464
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• 2021

본 연구는 강원지역 폐탄광 산림복구지에서 산림복구사업 후 시간경과에 따른 토양 화학적특성을 분석하여 관리방안 도출을 위해 수행하였다. 연구대상지는 강원도 정선군 5개 폐탄광과 영월군 3개 폐탄광 총 8개 폐탄광 산림복구지였으며, 경과시간별로 총 11회에 걸쳐 토양 화학적 특성을 분석하였다. 분석항목은 토양 pH, TOC, 총질소, 탄질률, 유효인산 등 5개 특성이었다. 분석결과 토양 pH와 유효인산 함량은 시간경과에 따라 감소하는 경향을, TOC와 총질소 함량, 탄질률은 증가하는 경향을 보였다. TOC와 총질소는 10년 경과시 폐탄광 산림복구를 위한 복토재의 품질기준을 만족하였으며, 토양 pH는 품질기준보다 낮아졌다. 따라서 산림복구사업후 토양 화학적 특성에 대한 장기모니터링 및 이를 통한 사후관리방안 수립이 필요하다.

• 디지털융복합연구
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• 제19권12호
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• pp.661-673
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• 2021

본 연구는 관상동맥중재술을 받은 남성의 건강행위 이행에 미치는 영향을 경과기간을 중심으로 파악하기 위한 서술적 상관관계 연구이다. 연구 대상자는 일개 대학병원에서 관상동맥중재술을 받은 남성 249명이며, 2017년 9월 1일부터 2018년 4월 30일까지 자료수집이 이루어졌다. 자료는 Stepwise multiple regression을 사용하여 분석하였다. 연구결과 건강행위 이행에 영향을 미치는 요인은 자기조절 중 자율적 동기(β=.35, p<.001), 교육요구도 중 위험요소(β=-.26, p<.001), 질병의 경과기간(β=.19, p<.001), 결혼 여부(β=.15, p=.001), 최종 학력(β=-.12, p=.035)이며, 총 설명력은 29.1%였다. 관상동맥 중재술을 받은 남성 환자의 건강행위 이행을 높이기 위해서는 중증도가 높고 경과시간이 1년 미만인 대상자의 자율적 동기를 강화할 수 있는 프로그램 개발이 필요하다.

• 한국운동역학회지
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• 제25권2호
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• pp.207-218
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• 2015

Objective : The purpose of this study was to investigate the characteristics of Gam-ki (double-arm winding) depending on the emotion being expressed. Gam-ki is one of the basic movements of Korean traditional dance. Method : We selected three Korean traditional dancers who belong to National Dance Company of Korea. They were asked to express four different emotions (anger, joy, sadness, and neutral) while performing Gam-ki. We analyzed elapsed time and time ratio, size of movement, ground reaction forces and ground impulses. Results : During Gam-ki the elapsed time for each phase as well as for one cycle was longest when "sadness" was expressed then followed by "neutral" and then "angry" and "joy." Except for the ankle in/eversion, the ROMs of the lower limb joints seem not to be an emotion-characteristic factor. The ROMs of the upper limb joints were largest when "anger" was expressed. Neck rotation is associated with expressing negative emotions ("angry" and "sadness"). For medial-lateral GRF "angry"> "joy" > "neutral" > "sadness" was in order. Therefore, it can be regarded as a factor indicating the activity of the emotion.

• 한국운동역학회지
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• 제17권2호
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• pp.23-29
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• 2007

The purpose of this study was to examine if there are kinematic variables differences between national representative players (NRP) and non national representative players (NNRP) during 500 m inline skate starting motion. Four NRP and six NNRP were recruited for the study. Each subject executed starting motion five times on a $2{\times}12m$ start way in a gymnasium. Kinematic variables were analyzed by the three-dimensional motion analysis system (60Hz). It was hypothesized that there are difference in elapsed time and center of mass acceleration in starting phase between groups since starting phase has been considered important in sprinting. The results showed that the NRP had significantly shorter starting phase time than that of NNRP. 1) An elapsed time in phase P1 of NRP was shorter than that of NNRP, and excellent players have early started their first stroke. 2) Both NRP and NNRP have started at the same spot, and displacement of the center of gravity in starting posture of NRP group was at the front compared to NNRP group. 3) Average step lengths of NRP were longer than those of NNRP, and a step change of NRP was stabler compared to that of NNRP. 4) In a speed change of the center of gravity NRP showed comparatively high speed from P1 to P4.