• 대한치과교정학회지
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• 제49권2호
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• pp.116-123
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• 2019

As an alternative to the conventional fixed appliance that uses orthodontic brackets, a simple round tube without a bonding base can be bonded to the tooth surface by covering the tube with flowable resin. In this technique, bent wires cannot be inserted into the simple tubes; therefore, repositioning of the simple tubes is often required for adjustments. To reduce repositioning of simple tubes, a dome-shaped resin covering of the simple tube can be designed with a customized in-and-out compensation, using three-dimensional computer-aided design software based on digital simulation of orthodontic tooth movement. In the present case, the use of simple tubes bonded with customized resin coverings in a Class I nonextraction case is described in a 17-year-old male, in whom moderate crowding of the anterior teeth was treated over an 8-month period. This case shows that simple tubes can be used as an alternative to brackets in some Class I nonextraction cases, with the potential benefit of reducing decalcification.

• 대한수학회보
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• 제52권5호
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• pp.1559-1568
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• 2015

The relative class number $H_d(f)$ of a real quadratic field $K=\mathbb{Q}(\sqrt{m})$ of discriminant d is the ratio of class numbers of $O_f$ and $O_K$, where $O_K$ denotes the ring of integers of K and $O_f$ is the order of conductor f given by $\mathbb{Z}+fO_K$. In a recent paper of A. Furness and E. A. Parker the relative class number of $\mathbb{Q}(\sqrt{m})$ has been investigated using continued fraction in the special case when $(\sqrt{m})$ has a diagonal form. Here, we extend their result and show that there exists a conductor f of relative class number 1 when the continued fraction of $(\sqrt{m})$ is non-diagonal of period 4 or 5. We also show that there exist infinitely many real quadratic fields with any power of 2 as relative class number if there are infinitely many Mersenne primes.

• 한국가정과교육학회지
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• 제30권1호
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• pp.115-128
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• 2018

본 연구는 교과역량 함양을 위한 가정과교육이 나아갈 방향을 모색해 보고자 하였다. 이를 위해 역량기반 가정과 수업의 현장 적용 방안을 탐색하고, 수업 사례를 개발하였다. 이 연구의 주요한 연구 결과는 다음과 같다. 첫째, 교과역량 함양을 위해서는 교육과정-수업-평가의 일체화를 통해 학생을 교육과정, 수업, 평가의 중심에 두어 삶의 주체로 성장시킬 수 있도록 해야 한다. 둘째, 교과역량 함양을 위해 교육과정-수업-평가 일체화를 중심으로 의생활 수업 사례를 개발하였다. 본 연구는 실제 가정과 수업에서 교과역량의 함양을 위한 교육과정-평가-수업의 일체화를 활성화 할 수 있을 것으로 기대된다.

• 한국수학교육학회지시리즈E:수학교육논문집
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• 제35권3호
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• pp.341-358
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• 2021

2020년 처음 발생한 코로나는 사회 전반에 많은 변화를 초래했다. 이러한 변화에 있어 교육 역시 예외가 아니었다. 학교에서는 사상 유례없는 온라인 개학을 시행했고 학생들과 교사는 충분한 준비 없이 원격수업에 참여해야 했다. 원격수업과 관련하여 관련 자료 개발, 만족도 조사와 같은 연구들이 수행되었으나 실제 학교 현장을 기반으로 한 연구는 없었다. 따라서 본 연구는 2020년부터 원격수업에 참여한 고등학교 학생들을 대상으로 하여 원격수업의 방식 및 만족도를 조사하고 원격수업 만족도와 수학학습과 관련된 하위요소들과의 관계를 탐색하였다. 연구결과 수학 교과에서는 원격수업이 대체로 실시간 쌍방향 수업의 형태로 이루어졌으며 학생들은 수학학습에 만족을 느꼈다. 하지만 원격수업을 지속해야 하는 것의 문제에 있어서 어느 정도 상반된 의견을 표명하였다. 또한, 통계분석 결과 원격수업에 대한 만족도에 따라 수학학습 의지, 전략, 수학에 대한 가치, 학습의욕 등에서 차이가 나타나는 것으로 드러났다.

• 패션비즈니스
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• 제7권6호
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• pp.85-91
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• 2003

Quick Response based Mass-Customization can be produced and distributed customized goods and services on mass basis in apparel e-business. Because consumers cannot touch and feel the apparel products in e-business, they tend to have the negative buying behavior. The purposes of this study were to analyze factors of texture image, and to investigate the differences of consumer sensibility on texture image of apparel products based on different marketing channels (on-line/off-line). Two types of questionnaires for on-line and off-line were used to assess consumer sensibility on apparel fabric. The 8 swatches were selected based on the previous literatures. 202 returned questionnaires for each type (on-line/off-line) were analyzed by t-test, mean and standard deviation with SPSS 10.0. The result of this study was showed that there were partially significant differences on consumer sensibility on texture image of apparel products between on-line and off-line. In case of corduroy, consumers perceived more high-class image under on-line than off-line. In case of taffeta, consumers perceived more thin and dense image under off-line (traditional marketing channel) than on-line (e-commerce). In case of denim, consumers perceived more thin and natural image under off-line than online. In case of organza, consumers perceived more natural image under on-line than off-line. In case of satin, consumers perceived more natural image under on-line than off-line. In case of chiffon, consumers perceived denser image under on-line than off-line. In case of velvet, consumers perceived thinner image, higher-class image, and more natural image of texture sensibility under on-line than off-line. In case of single jersey, consumers perceived higher-class image, and denser image of texture under on-line than off-line.

• Journal of Periodontal and Implant Science
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• 제23권3호
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• pp.475-492
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• 1993

The effect of synthetic bone materials was assessed in the patients with pure periodontal class II and III furcation defects. The buccal aspects of the maxillary and mandilular first and second molars were surgically exposed, and synthetic bone materials were interposed between the gingival flap and the furcation defects in the experimental group. The control group were treated without the use of synthetic bone materials by same operator. Probing pocket depth, gingival recession, and loss of attachment, were measured by Michigan O-probe and tooth mobility was evaluated by an electronic mobility tester(Periotest(R), Siemens co. Germany) at preoperation and 3-, 6-, and 12-month postoperation. Standardized radiogrphs were taken at preoperation and 6-month and 12-month postoperation. The postoperative change of clinical parameters and the difference between experimental group and control group were statistically analyzed by Student, t-test. The results were as follows: 1. The probing pocket depth at the 3-, 6-, and 12-month postoperative examination was significantly decreased, compared to that at preoperative examination in both experimental group and control group(P<0.005), but there was no significantly difference between experimental group and control group. 2. The amount of gingival recession at the 3-, 6-, and 12-month postoperative examination was increased, compared to that at the preoperative examination in both experimental and control group(P<0.005). In the case of the class III furcation involvement, the amount of gingival recession at the 3-, 6-, and 12-month postoperative examination was more significantly increased in control group than experimental group(P<0.05). 3. The amount of loss of attachment at the 3-, 6-, and 12-month postoperative examination was significantly decreased, compared to that at the preoperative examination in both experimental and control group in the case of class II furcation involvement, and in experimental group only in the case of furcation III involvement(P<0.005). The amount of loss of attachment at, the 3-, 6-, and 12-month postoperative examination was more significantly decreased in experimental group than control group in the case of the class III furcation involvement(P<0.05), but in the case of class II furcation involvement there was no significant difference between experimental group and control group. 4. The tooth mobility at the 3-, 6-, and 12-month postoperative examination was significantly decreased, compared to that at the preoperative examination in both experimental and control group(P<0.005), but there was no significant difference between experimental group and control group. 5. Radiopacity of furcation area was greatly increased in the experiment group, but there was no radiographic change in the control group.

• 한국가정과교육학회지
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• 제31권1호
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• pp.77-88
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• 2019

본 연구에서는 사범대 가정교육과 학생들을 대상으로 가정생활문화 수업에서 학습자중심의 교수학습방법인 플립러닝(flipped learning)을 적용한 역진행 수업(Inverted Class)을 진행하고 그 효과를 살펴보았다. 플립러닝 수업은 3단계(Pre class/In class/After class)로 설계하였으며, 수업 효과를 알아보기 위해 가정교육과 40명의 대학생을 대상으로 플립러닝 수업 만족도 설문조사를 실시하였고, 매주 수업 종료 후 학생들이 작성한 WorkSheet와 성찰일지를 살펴보았다. 학생들은 일방적 강의에서 탈피하여 질문과 토론 등 어울림 수업을 할 수 있어서 좋았으며, 선행학습 또는 개별적으로 학습할 때 병행학습이 가능하여 학습효과가 높아 플립러닝 수업에 대한 만족도가 높은 것으로 나타났다. 특히, Visual Thinking을 활용한 수업은 흥미로웠으며, 학습내용을 이해하고 정리(요약)하는데 유용하여 다른 전공분야 학습에 적용시킬 의지도 높게 나타났다. 이와 같이 플립러닝을 적용한 수업을 가정생활문화 수업에 활용해 보는 것은 학습자 중심의 교수학습 방법으로 긍정적인 학습 효과를 가진 것으로 나타나, 4차 산업혁명 시대의 미래인재양성을 위한 효과적인 학습자 중심의 교수학습 방법으로 앞으로의 중등교육에도 활용될 것으로 기대한다.

• 대한소아치과학회지
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• 제25권3호
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• pp.604-612
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• 1998

The majority of Class III malocclusion have maxillary retrusion. Thus, it becomes obvious that management of most skeletal Class III malocclusion cases should include maxillary protraction as major objective. Additionally, in Class III malocclusion with posterior crossbite, RME "disarticulates" the maxilla and initiates cellular response in the sutures, allowing a more positive reaction to protraction forces. Using facemask with RME helped in correction of skeletal Class III malocclusion by the anterior displacement of maxilla and maxillary dentition, and changing the direction of the growth of mandible. Thus, acceptable improvement in the Class III profile was performed.

• 실천공학교육논문지
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• 제9권2호
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• pp.125-132
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• 2017

본 논문은 효과적인 학습을 제공해주는 교수법으로 알려진 플립러닝을 신호처리 교과목에 적용한 사례에 대한 연구이다. 수업을 위해 사용된 교수학습 모형과 3개년간 시행 사례를 기술하였다. In-class는 비교적 성공적인 수업이라 판단할 수 있으나, Pre-class에서 제공된 동영상 자료의 편성과 학습 여부에 대한 평가는 개선이 필요하였다. 또한, Pre-class와 In-class를 효과적으로 연계하는 방법에 대한 연구가 필요하다고 판단된다.

• 한국환경과학회지
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• 제8권3호
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• pp.281-286
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• 1999

This study was conduced to examine the monthly and seasonal variation of $SO_2$, TSP, $O_3$ concentration in Dongsamdong, Pusan coastal area. And the characteristics of air pollution of this area was compared to Kwangbokdong in Pusan and Taehadong in Ullungdo. Monthly mean concentration of $SO_2$ and TSP showed lower than Kwangbokdong, $O_3$ was higher than Kwangbokdong. In case of $SO_2$, seasonal variation of Dongsamdong was remarkabler thn Kwangbokdong and the concentration difference of early morning and daytime was higher than Kwangbokdong. Taehadong showed very lower concentration as background area. In case of TSP, Dongsamdong was lower concentration and smaller diurnal change than Kwangbokdong, Taehadong showed very lower concentration as backgound area. In case of $O_3$, Dongsamdong was 10ppb higher than Kwangbokdong at daytime maximum concentration, diurnal change of concentration was higher, too. In case of frequency distribution of concentration, $SO_2$, and TSP at Dongsamdong showed higher frequency in low concentration class and $O_3$ showed in high concentration class as compared with Kwangbokdong.