• Restorative Dentistry and Endodontics
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• 제28권5호
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• pp.363-368
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• 2003

The purpose of this study is to evaluate the effect of additional enamel etching with phosphoric acid on the microleakage of the adhesion of self-etching primer system. Class V cavity($4mm{\times}3mm{\times}1.5mm$) preparations with all margins in enamel were prepared on buccal surface of 42 extracted human upper central incisor teeth. Prepared teeth were randomly divided into 3 groups. Group 1：no additional pretreatment with 37% phosphoric acid (NE). Group 2：additional pretreatment with 37% phosphoric acid for 10 seconds (E10s). Group 3：additional pretreatment with 37% phosphoric acid for 20 seconds (E20s). The adhesives(Clearfil SE $Bond^{\circledR}$, Kuraray, Osaka, Japan) and composite resins(Clearfil $AP-X^{\circledR}$, Osaka, Kuraray, Japan) were applied following the manufacturer's instructions. All the specimens were finished with the polishing disc(3M dental product, St Paul, MN, USA), thermocycled for 500 cycles between $5^{\circ}C$ and $55^{\circ}C$ and resected apical 3-mm root. 0.028 stainless steel wire was inserted apically into the pulp chamber of each tooth and sealed into position with sticky wax. Surrounding tooth surface was covered with a nail varnish 2 times except areas 1mm far from all the margins. After drying for one day, soaked the samples in the distilled water. Microleakage was assessed by electrochemical method(System 6514, $Electrometer^{\circledR}$), Keithley, USA) in the distilled water. In this study, the microleakage was the lowest in group 1 (NE) and the highest in group 3(E20s)(NE

• Mycobiology
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• 제36권3호
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• pp.143-147
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• 2008

We have detected the slime mold, Diachea leucopodia (GNU06-10) in a strawberry greenhouse located in Sancheong-gun, Gyeongnam. Typical fruiting bodies had developed gregariously on the strawberry leaves, petioles, and plant debris on ground soil habitat, and also surprisingly on plastic pipes and a vinyl covering. Field samples were examined via stereomicroscopy, light microscopy, and SEM for the determination of morphological characteristics. Dark-brown to black spores formed gregariously within the stipitate cylindrical sporangium, and were covered by an iridescent peridium, which may be intact at maturity, or may have disintegrated. The upper portion of the peridium generally breaks up to expose the spores, whereas the lower portion was usually persistent. The results of energy dispersive X-ray spectrometer (EDS) analysis showed that lime was present in the stalk and columella but absent from the spores, capillitium, and peridium. The above characteristics confirm its taxonomic position in the genus Diachea. However, this genus is intermediate in character between the Physarales and Stemonitales of the Myxogastromycetidae. Hence, this genus had been classified as a member of the Stemonitales until the mid-1970's, on the basis of its iridescent peridium and noncalcareous capillitial system, similar to Comatricha of the Stemonitaceae. By way of contrast, emphasis on morphological characteristics, most notably the calcareous stalk and typical columella, places Diachea within the order Physarales. The presence of a phaneroplasmodium during the trophic stage and lime deposition in its sporophores, as was confirmed in this work, supported the inclusion of Diachea in the Physarales, and the noncalcareous capillitial system verified its identification as a member of the Didymiaceae. Further characteristics of the species D. leucopodia include the following: phaneroplasmodium, spore globose 7.5 ${\mu}m$ in diameter, very minutely roughened; sporangia $500{\mu}m\times1mm$, more or less cylindrical, gregarious, stalked 1.2mm; stalk and columella white.

• 한국콘텐츠학회논문지
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• 제18권12호
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• pp.421-431
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• 2018

본 연구는 우리나라에서 '전통' 용어의 트렌드를 분석하기 위해 과거 신문기사를 수집하여 텍스트 마이닝 기법과 소셜네트워크분석 기법을 수행하였다. 이러한 문헌을 분석하는데 있어서 과거의 해석적 연구 방법을 사용하지 않고 비정형 텍스트 자료에 근거한 정량적 분석을 통해 '전통' 논의들이 신문기사에서는 어떻게 보도되어 왔는지를 분석해봄으로써 우리사회 '전통' 용어의 동향을 파악하였다. 분석 대상은 1920년대부터 2017년까지 미디어에 등장한 '전통' 관련 신문기사 2,481,143건을 수집하였다. 다음으로 시대별 신문기사에 대한 빈도분석을 통해 '전통' 관련 어떤 키워드들이 자주 나타나고 있는지에 대해 파악하였다. 또한 '전통' 관련 키워드들간 연관어 분석을 통해 '전통' 키워드의 연결 맥락을 파악하였다. 마지막으로 소셜네트 워크분석을 통해 키워드들간에 유기적인 관계를 분석하고 군집화하였다. 이러한 텍스트 마이닝 기법을 적용함으로써 객관적이고 가치 중립적인 입장으로 '전통' 관련 사회문화현상에 대한 의미를 포착하고 시대별 '전통'이 담고 있는 사회적 상징성을 파악할 수 있다.

• 한국콘텐츠학회논문지
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• 제22권1호
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• pp.116-125
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• 2022

넷플릭스 오리지널 영화는 극장 개봉 없이 온라인으로만 상영되며 관람자가 개인용 기기를 이용해 영화를 관람한다는 측면에서 기존의 영화와는 차별화된 특성을 가진다. 넷플릭스 플랫폼의 촉각적 특성을 재매개 관점에서 분석함으로써 클릭 또는 터치를 수반하는 넷플릭스 하이퍼매개 촉각성이 비매개 촉각성으로 확장해 나가는 방식과 특성을 살펴보며, 넷플릭스 오리지널 영화 <레베카>(2020)와 필름 영화 <레베카>(1940)의 촉각 표현 방식 차이점을 비교 분석한다. 이를 통해 넷플릭스 매체 특성인 클릭 또는 터치를 필요로 하는 손의 감각과 넷플릭스 오리지널 영화 <레베카>의 손의 촉각 묘사의 연관성을 짚어낸다. 개인용 기기의 개별 인터페이스를 조정해야만 영화 관람이 가능해진 시대로 변모해감에 따라 영화 관람에서 손의 지위가 중요해지면서 영화 관람의 시작과 중간, 끝 모든 과정에서 손은 필수적인 역할을 담당한다. 따라서 넷플릭스 오리지널 영화 <레베카>의 손의 촉각적 특성을 중심으로 살펴본 본 연구는 기존 연구에서 다루지 않았던 OTT 오리지널 영화의 특성을 연구했다는 점과 OTT 관람 방식에 손의 촉각성이 중요하게 작용된다는 점을 밝힌다는 점에서 의의를 가진다

• 한국산학기술학회논문지
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• 제22권5호
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• pp.98-107
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• 2021

차기군수지원함(AOE-II) 풍향풍속계 장비에 대해서 항해시운전평가 결과, 함의 우현에서는 40~90도 부근, 좌현에서는 270~320도 부근에서 풍향풍속 검출기 움직임 오작동 현상이 발생되었다. 위의 현상에 대한 원인을 분석하고 개선하는 것이 본 연구의 목적이었다. 원인 추정으로 풍향풍속 검출기가 마스트 구조물에 가려져서 불어오는 바람의 직접적인 영향을 받지 않게 되고, 마스트 구조물 뒤쪽으로 와류 기류가 형성되어 움직임 오작동 현상을 발생시켰다고 추정하였다. 위의 문제를 해결하기 위해서 신규 설치되는 마스트 야드에 풍향풍속 검출기를 이동 설치하는 방안을 검토하였다. 진동 해석을 실시하여 진동 영향성을 검토 후 신규 마스트 야드에 풍향풍속 검출기를 설치하여 항해시운전평가로 검증하였다. 개선 방안이 일부 유효하여, 신규 마스트 야드에서 풍향풍속 검출기 위치를 마스트와 이격하여 이동 설치 후 항해시운전평가로 다시 검증하였다. 풍향풍속 검출기 움직임 오작동 현상이 더 이상 발생하지 않아서 적절한 개선방안으로 확인되었다.

• Human Ecology Research
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• 제61권3호
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• pp.493-503
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• 2023

Since ISO 20471 regulations(2013) were enacted, high-visibility clothing made of fluorescent fabric and retroreflective materials has been standardized to distinguish the wearers from the surrounding background in a dark place and to protect them. Accordingly, we made high-visibility safety clothing based on the international standards, and examined the positions of the retro-reflective materials on the attached sites to evaluate the suitability of the positions, by 3 types of safety clothing and the body regions when the wearers work or move. Two retro-reflective films of 5cm-horizontal lines were attached to the front/back of the upper-wear, and the lower-wear. Vertical lines were attached from the shoulder to the horizontal waistline. To analyze the motion in 3-dimension, we took pictured infrared-reflective markers on the retro-reflective film covered with yellow-tape on the front-side when 6 subjects wearing experimental garments performed 6 types of motions. According to the metronome tempo, the motions were performed for 30 seconds and repeated 6 motions ①~⑥ by 3 experimental clothing. Among the 6 motions, significant differences in the appearance rate of the markers by body region during the motions were found in 5 types except for motion ③. Significant differences by the post-hoc test were shown in motions ④ and ⑥ as well. Therefore, for high-visibility safety clothing, it is necessary to anticipate the worker's motion and consider the attaching position of the retro-reflective material. It is considered desirable to attach the retro-reflective materials to several places where the clothing is hard to wrinkle.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2017년도 춘계공동학술대회
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• pp.156-156
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• 2017

Most crop damages have been occurred by vermin(e.g., wild birds and herbivores) during the period between seeding and the cotyledon level. In this study, to minimize the damage by vermin and acquire the benefits such as protection against weeds and maintenance of water content in soil, immediately vinyl mulching after seeding was devised. Vinyl mulching has been generally covered with black color vinyl, that crop seeding locations cannot be detected by visible light range. Before punching vinyl, non-contact and non-destructive methods that can continuously determine the locations are necessary. In this study, a crop position detection method was studied that uses infrared thermal image sensor to determine the cotyledon position under vinyl mulch. The moving system for acquiring image arrays has been developed for continuously detecting crop locations under plastic mulching on the field. A sliding mechanical device was developed to move the sensor, which were arranged in the form of a linear array, perpendicular to the array using a micro-controller integrated with a stepping motor. The experiments were conducted while moving 4.00 cm/s speed of the IR sensor by the rotational speed of the stepping motor based on a digital pulse width modulation signal from the micro-controller. The acquired images were calibrated with the spatial image correlation. The collected data were processed using moving averaging on interpolation to determine the frame where the variance was the smallest in resolution units of 1.02 cm. For this study, the spline method was relatively faster than the other polynomial interpolation methods, because it has a lower maximum order of formulation when using a system such as the tridiagonal linear equation system which provided the capability of real-time processing. The temperature distribution corresponding to the distance between the crops was 10 cm, and the more clearly the leaf pattern of the crop was visually confirmed. The frequency difference was decreased, as the number of overlapped pixels was increased. Also the wave pattern of points where the crops were recognized were reduced.

• 한국과학교육학회지
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• 제15권4호
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• pp.379-393
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• 1995

In spite of school science learning, the students' conceptions have not been changed easily. Therefore, to make students overcome their non scientific conceptions has been an important issue in science education. The purpose of this study was to identify the conceptions of students and teachers on the motion of the earth and the moon. The instrument was developed for estimating students' understandings of the concepts related to the motion of the earth and the moon. The validity of the instrument was examined by the specialists in Science Educator and Astronomer. At the same time, the two field trials had been executed, and the items were modified. Also, it consists of 12 items including 9 two-tier multiple choice items and 3 multiple choice items. The population of this study consists of 250 eighth-, 299 tenth-, 292 eleventh-grade students, 134 science teachers in secondary school. SPSS/PC+ was adopted for the statistical analysis. The type of misconceptions possessed students were as follows: 1) At 12:00 noon, the sun is directly overhead. 2) First quarter moon is a half of overall surface of the moon. 3) Air don't rotate with the earth surface because it keeps apart from the earth surface. 4) Summer is warmer than winter, because the earth is nearer from the sun in summer. 5) Whenever season is changed, the direction of rotation axis of the earth is changed. 6) The moon is the brightest at the position of new moon, because the distance between the moon and the sun is the shortest and the moon is received strongest sunlight. 7) The moon is not seen at the position of real full moon, because it is covered with shadow of the earth. 8) When the moon is not seen in the earth, sunlight is not reached at the moon. The major findings were as follows : 1) The middle school students had more misconceptions than those of high school students. And female students had more misconceptions than those of male ones. 2) The rate of correct answer and the type of conception in the tenth grade students were very similar with eleventh grade students. 3) The higher cognitive level, the better development of scientific conception and the less misconception. Also, the correlation coefficient between scientific conception score and GALT score was 0.57. 4) The students in scientific part had higher the rate of correct answer than those of students in human part and the former had less misconception than the latter. 5) The rate of correct answer about model and figure items was lower than descriptive ones, because they did not understand about figures itselves. These types of misconceptions will be used for science instruction and studies of other conceptions need.

• The Korean Journal of Pain
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• 제1권1호
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• pp.47-52
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• 1988

Since 1979 forty-three cancer patients have been given intrathecal block at the pain clinic of Yonsei Medical Center. The male patients numbered 23 and female 20 and most of them were in the 4th and 5th decades of age. In 78.6% of the patients, the diagnosis was rectal cancer in 20 cases, cervix cancer in 7 cases, bladder cancer in 4 cases and colon cancer in 3 cases. Thirty six patients with cancer pain were treated by intrathecal 10% phenol-glycerine block and rest of them had only test block. Fourteen patients whose pain sites were lumbar or lumbar and upper sacral dermatomes were put into the lateral recumbent position on the fluoroscopic table. The spinal puncture was performed as close to the spinal roots to be impregnated as possible. In 22 patients the pain sites were covered by the sacral dermatomes and so the L5-S1 interspace was punctured in the sitting position shifted 15 degree to the affected site. Fifty one blocks were performed and their results are classified into three categories: good, fair antral poor. We achieved good results in 38 patients(77.1%), fair in 6 patients(17.1%) and poor in 2 patient(5.7%). Thus a satisfactory pain relief was achieved in 94.2% of patients. After intrathecal block with phenol glycerine, transient voiding difficulty was noted in 7, defecation difficulty in 1, and transient paresthesia and/or muscle weakness was present in 3 patients. The mean duration of pain relief was 2.5 months and longer than the mean survival time of 2.25 months. When patients are selected carefully and tile block is performed with great caution and good technique, the risk is minimal and a long lasting relief of intractable cancer pain achieves a painless life until death.

• 한국산림과학회지
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• 제89권3호
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• pp.397-404
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• 2000

임도 옆도랑침식에 영향을 미치는 요인의 평가 및 안정도 판별을 위하여 광릉시험림의 임도를 대상으로 조사를 실시한 결과 침식에 미치는 기여순위는 종단물매, 시설위치, 절토사면경사, 절토사면구성물질, 유하거리, 노면형태, 노면재료, 절토사면피복도, 절토사면길이 순으로 나타났다. 임도 옆도랑침식을 유발하는 요인을 평가하면, 종단물매는 8% 이상, 임도시설위치는 산록(山麓)과 중복(中腹), 절토사면경사는 $50^{\circ}$ 이상, 절토사면토성은 견질토사, 자갈섞인 토사, 호박돌섞인 토사, 유하거리는 80m 이상의 지역에서, 그리고 노면재료는 토사도(土砂道)와 자갈부설도에서, 노면형태의 경우에는 철(凸)형과 직선형, 절토사면 피복도(被覆度)는 피복도가 중(中)이상인 곳에서 임도 옆도랑침식이 발생할 가능성이 높은 것으로 예측(豫測)되었다.