• 제목/요약/키워드: difference of proportions

검색결과 210건 처리시간 0.029초

단위중량 2,000kg/㎥급 고강도 시멘트 복합체 개발을 위한 기초연구 (Preliminary Study on Development of High Strength Cement Composites at 2,000kg/㎥ of Specific Weight)

  • 정연웅;임귀환;강용학;정상화;김주형
    • 한국건설순환자원학회논문집
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    • 제8권4호
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    • pp.562-570
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    • 2020
  • 본 연구에서는 단위중량 2,000kg/㎥ 이하의 고강도 시멘트 복합체 제조기술 및 기초 물성을 탐구한다. 선행연구에서 제시한 초고성능콘크리트의 배합에서 잔골재를 경량 재료인 솔리드 버블과 경량잔골재로 치환하여 경량 고강도 시멘트 복합체를 제조기술을 제안한다. 솔리드 버블을 혼입한 시멘트 복합체는 밀도 2.0g/㎤ 이하에서 재령 28일 강도 116MPa~141MPa의 고강도 발현이 가능한 것으로 나타났다. 경량잔골재를 사용하는 경우 솔리드 버블을 혼입한 시멘트 복합체보다 역학적 성능이 떨어지는 것으로 나타났다. 배합표상에서 계산된 단위용적중량과 경화된 시멘트 복합체의 밀도가 큰 차이를 보이지 않았으며, 이는 배합표상에서 계산된 단위용적중량을 통해 경화된 시멘트 복합체의 밀도를 추정할 수 있는 것을 보여준다.

문헌정보학 분야의 통계기법 사용에 관한 계량적 연구 (A quantitative analysis of the use of statistics in library and information science)

  • 사공철;최정희
    • 한국도서관정보학회지
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    • 제20권
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    • pp.31-60
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    • 1993
  • The purpose of this study is to analyze quantitatively the use of statistics, especially inferential statistics, in library and information science. Thus this study compared the use of statistics in library and information science with it in social work and education. The results of this study are as follows: First, the result is that, when the proportions of articles in each of the three categories of use are compared, library and information science is deficient in the use of inferential statistics and unusually productive of articles in 'No Statistics' category and 'Descriptive Statistics Only' category. Second, ANOVA showed no significant difference in the means for number of articles with no statistics and for articles with descriptive statistics only, but did show a statistically significant difference for the means for number of articles with inferential statistics. That is, the use of inferential statistics in library and information science was very less than the other subject areas. Third, a comparison of the numbers of various inferential statistics for each of the three subject areas indicated that the differences were not significant. This fact means that the quality of inferential statistics used in library and information science was similar to the other subjects.

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허리가 가는 여성의 하반신 체형 분석 (Lower Body Shape Analysis of Women with a Slender Waist)

  • 차수정
    • 한국의류학회지
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    • 제47권5호
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    • pp.853-872
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    • 2023
  • This study analyzed the body shape of adult women aged 20 to 59 with a waist and hip circumference difference of 22.00 cm or more to characterize the lower body shape of women with slender waist. The researchers analyzed the data using SPSS 26.0. Among the lower body measurements of women with slender waists, the waist circumference was 70.79 cm and the hip circumference was 95.25 cm, with a difference of 24.56 cm between the waist and hip circumferences. We categorized the components of a slender waist body type into four factors: lower body horizontal, lower body vertical, lower calf horizontal, and hip and crotch length. We categorized women with slender waists into four body types: slender long crane legs, short thick lamb legs, short thin ladder legs, and thick long pole legs. In their twenties, many people have slender, long-legged lower body, but as they age, they are more likely to have thicker lower bodies and short, thin ankles. Body types with slender waist had larger proportions of abdominal and hip dimensions in the width, circumference, and thickness categories based on waist dimensions than those with average or thick waists.

Biometry of width between labial transitional line angles in anterior teeth: an observational study

  • Wen, Chao;Ye, Hongqiang;Chen, Hu;Zhou, Yongsheng;Huang, Mingming;Sun, Yuchun
    • The Journal of Advanced Prosthodontics
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    • 제14권1호
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    • pp.1-11
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    • 2022
  • PURPOSE. The maximum width between the mesial and distal labial transitional line angles, described as "esthetic width" herein, could significantly influence the visual perception of the teeth and smile. This study aimed to conduct biometric research on esthetic width and to explore whether regular distribution exists in the esthetic width of human teeth. MATERIALS AND METHODS. A total of 4,264 maxillary and mandibular anterior teeth were measured using the Geomagic studio software program. The proportions of maxillary to mandibular homonymous teeth and proportions between the adjacent teeth were calculated. Bilateral symmetry and the correlation between the esthetic and mesiodistal widths were both accounted for during the measurement procedures. RESULTS. The mean esthetic widths were 6.773 ± 0.518 mm and 4.329 ± 0.331 mm for maxillary and mandibular central incisors, respectively, 5.451 ± 0.487 mm and 5.008 ± 0.351 mm for maxillary and mandibular lateral incisors, respectively, and 3.340 ± 0.353 mm and 5.958 ± 0.415 mm for maxillary and mandibular canines, respectively. Except for the mandibular canines, no significant difference in esthetic width was found among homonymous teeth from the same jaw. A high linear correlation was found between the esthetic and mesiodistal widths of the same tooth, except for the maxillary canines. Esthetic width proportions among different tooth categories showed some regular patterns, which were similar to those of the mesiodistal width. CONCLUSION. Esthetic width is regularly distributed among the teeth in the Chinese population. This could provide an important reference for anterior dental restorations and dimension recovery in esthetic reconstruction of anterior teeth.

국내의 지역 및 계절에 따른 콘크리트 배합별 환경영향평가 (Environmental Impact Assessment of Different Concrete Mixture Proportions according to Domestic Region and Season)

  • 서은아;양근혁;정연백
    • 콘크리트학회논문집
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    • 제26권3호
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    • pp.239-245
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    • 2014
  • 지역과 계절이 콘크리트의 전과정 환경영향에 미치는 효과를 정량적으로 평가하기위해 6331개의 레디믹스 콘크리트 배합을 분석하였다. 콘크리트의 환경영향은 국가 생애주기 데이터목록을 기반으로 산출한 환경부하 발생량을 분류화, 특성화, 정규화 및 가중치 단계를 거쳐 6가지 환경영향 범주(지구온난화, 자원고갈, 광화학산화물생성, 산성화, 부영향화, 인간독성)로 나타났다. 단위압축강도에서의 환경영향 지표를 평가하기 위해 콘크리트 압축강도로 무차원한 환경영향 지수로 정의하였다. 국내에서 가장 많이 사용되는 콘크리트의 압축강도($f_{ck}$)는 24 MPa와 27 MPa이다. $f_{ck}$이 24 MPa일때 환경영향 지표가 가장 낮은 지역은 울산이었으며 가장 높은 지역은 광주와 대구였다. 지역에 따른 환경영향의 차이는 지역에 따라 사용되는 혼화재의 종류와 치환율이 다르기 때문이다. 또한 압축강도 24 MPa일때, 콘크리트의 환경영향지수는 동절기가 하절기 및 표준기에 비해 약 5% 높았다. 반면에 콘크리트의 환경영향 지수는 콘크리트 압축강도가 35 MPa을 넘어서면서 계절의 영향은 미미하였다.

소 난관 상피세포의 배양 상층액에서 생쥐 배의 체외발달 (In Vitro Development of Mouse Embryos in Culture Supernatant of Bovine Oviductal Epithelial Cell)

  • 김선구
    • 한국가축번식학회지
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    • 제22권2호
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    • pp.111-117
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    • 1998
  • This study was conducted to examine the effect of culture supernatant of bovine oviductal epithelial cell(BOEC) on in vitro development of mouse embryos. To obtain the culture supernatant, ampullary epithelial cell, ithmic epithelial cell and ciliated eptithelial cell of bovine oviduct were cultured in Ham's F-10 su, pp.emented with 10% FCS. The development rates of mouse embryos to blastocyst stage were significantly(P<0.05) higher in BOEC-culture supernatant(72.3∼82.3%) than in Ham's F-10(50.7%). The proportions of embryonic development into hatched blastocysts were significantly(P<0.05) higher in ampullary cell supernatant(43.2%), ithmic cell supernatant(48.4%) and ciliated cell supernatant (27.7%) than in Ham's F-10(14.4%). On the other hand, the effect of ciliated cell supernatant was lower than those of other cell supernatants(P<0.05). And there was no difference between ampullary cell supernatant and ithmic cell supernatnat.

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패션 트렌드 정보 키워드에 따른 국내 이국적 이미지 상품 분석 - $2001{\sim}2006$년 여성복을 중심으로 - (The Analysis of Exotic Images in Domestic Fashion Brand Items by Fashion Trend Information - Focusing on the Women's Wear from 2001 to 2006 -)

  • 이미연
    • 복식문화연구
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    • 제15권4호
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    • pp.634-646
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    • 2007
  • The aim of his study is to understand the developed aspect and proportions of the exotic images. Thus, this analyzed the exotic images in domestic fashion brand items as an relevance with fashion trend information. The exotic images are in the order of 'ethnic', 'retro', artistic', 'elegance', 'primitive', 'seductive', 'folklore', 'extreme hybrid', 'romantic', 'natural', 'splendid', 'bohemian', 'classical', 'kidult', 'modern', 'traditional', 'vintage' expressed in domestic fashion goods by the categories of its key-words expressed fashion trend information, and suitable for the fashion trend in 21C and fashionable for goods in the domestic fashion market by expressing the racial costume images and retro look, the maximized women's elegance, the difference images with an humor and unfamiliarity.

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Soybean Oil 및 Flaxseed Oil 첨가 배양시 탄수화물 첨가수준에 의한 반추미생물의 Bio-hydrogenation과 CLA 생성에 미치는 효과 (Effect of the Level of Carbohydrates on Bio-hydrogenation and CLA Production by Rumen Bacteria When Incubated with Soybean Oil or Flaxseed Oil In vitro)

  • 최성호;임근우;김광림;송만강
    • Journal of Animal Science and Technology
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    • 제48권4호
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    • pp.521-532
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    • 2006
  • 본 실험은 대두유 또는 아마유를 in vitro 방법으로 배양 할 때, 탄수화물원의 첨가수준이 반추위 박테리아에 의한 bio-hydrogenation과 CLA 생성에 미치는 효과를 조사하였다. 4수준(0%, 0.3%, 0.6% 그리고 0.9%, w/v)의 혼합된 탄수화물원(glucose, cellobiose, soluble starch, 1:1:1, w/w/w)과 두 종류의 oil을 cellulose powder에 흡착시킨 형태로 각각 60mg씩 인공타액(120ml)과 반추위액(30ml)이 혼합된 배양액(150ml)에 넣은 다음 39℃에서 12시간동안 혐기적으로 배양하였다. 배양액의 pH와 암모니아 농도는 두 종류 oil을 첨가한 배양액 모두에서 탄수화물원의 첨가 수준이 높을수록 pH와 암모니아 농도가 낮았다(P<0.05). 탄수화물원의 첨가 수준이 증가할수록 total VFA 생성량 역시 증가되었으나(P<0.01) 첨가한 oil 간의 차이는 없었다. 배양시간이 경과됨에 따라 탄수화물원의 첨가수준이 높을수록 propionate의 조성비율이 증가된 반면(P<0.001) acetate와 butyrate의 조성비율은 감소되었다. 배양 후 3시간이 경과하였을 때 배양액 내 oleic acid의 조성비율은 대두유에 비하여 아마유를 첨가한 배양액에서 낮았으나(P<0.001) linoleic acid의 비율은 높았다(P<0.001). 이와는 달리 탄수화물원의 수준이 증가될수록 stearic acid(P<0.05), CLA(P<0.01) 및 cis-9, trans-11 CLA(P<0.001)의 조성비율은 감소되었으나, linoleic acid의 조성 비율은 증가되었다(P<0.05). Linolenic acid의 조성비율에 있어서는 첨가된 oil의 종류와 첨가된 탄수화물원의 수준간의 상호작용이 있는 것으로 나타났는데(P<0.001), 12시간의 배양종료 후 대두유 첨가구에 비해 아마유 첨가구에서 stearic acid(P<0.01), oleic acid(P<0.001), 그리고 trans-11C18:1(P<0.01)의 조성비율이 감소된 반면, linoleic acid(P<0.001)와 linolenic acid(P<0.01)의 조성비율은 증가되었다. 탄수화물원의 첨가수준이 증가될수록 stearic acid와 총 CLA의 조성비는 감소되었으나(P<0.01), trans-11-C18:1(P<0.05)와 linoleic acid(P<0.01)의 조성비율은 증가되었다. 배양 12시간 후 배양액 내의 oleic acid (P<0.05), linoleic acid(P<0.05) 및 linolenic acid(P<0.01)의 조성비율에 있어서는 첨가한 oil의 종류와 첨가한 탄수화물원의 수준간의 상호작용이 있었는데, 탄수화물원의 첨가수준이 감소됨에 따라 cis-9, trans-11 CLA와 trans-10, cis-12 CLA의 조성비 역시 감소되는 경향이었으나 첨가한 oil의 종류에 대한 영향은 거의 받지 않았다. 본 실험의 결과를 종합해 볼 때, 탄수화물의 첨가수준과 oil의 첨가는 반추미생물의 bio-hydrogenation 작용 및 CLA 생성에 영향할 수 있는 것으로 여겨진다.

Auricle reconstruction with autologous costal cartilage versus polyethylene implants in microtia patients: a meta-analysis

  • Yun Jung Kim;Kyunghyun Min;Kyunghyun Min;Tai Suk Roh;Hyun-Soo Zhang;In Sik Yun
    • 대한두개안면성형외과학회지
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    • 제25권4호
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    • pp.179-186
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    • 2024
  • Background: Auricle reconstruction is among the most challenging procedures in plastic and reconstructive surgery, and the choice of framework material is a critical decision for both surgeons and patients. This meta-analysis compared the outcomes of autologous auricle reconstruction using costal cartilage with those of alloplastic reconstruction using porous polyethylene implants. Methods: A literature review was conducted using the PubMed and Embase databases to retrieve articles published between January 2000 and June 2024. The outcomes analyzed included postoperative complications such as framework exposure, infection, skin necrosis, hematoma, and hypertrophic scars, as well as patient satisfaction. The proportions of reconstructive outcomes from each selected study were statistically analyzed using the "metaprop" function in R software. Results: Fourteen articles met our inclusion criteria. The group undergoing polyethylene implant reconstruction exhibited higher rates of framework exposure, infection, and skin necrosis, whereas the autologous reconstruction group experienced higher rates of hematoma and hypertrophic scars. Of all the complications, framework exposure was the only one to show a statistically significant difference between the two groups (p< 0.0001). In terms of patient satisfaction, those who underwent autologous cartilage reconstruction reported a higher rate of satisfaction, although this difference did not reach statistical significance in the meta-analysis (p= 0.076). Conclusion: There is no statistically significant difference in postoperative complications such as infection, hematoma, skin necrosis, and hypertrophic scars between auricle reconstructions using autologous costal cartilage and those using polyethylene implants. However, reconstructions with polyethylene implants show a significantly higher rate of framework exposure.

Sassouni분석법에 의한 한국 아동의 두개, 안모, 치아의 상호관계 변화에 관한 누년적 연구 (A LONGITUDINAL ROENTGENO-CEPHALOMETRIC STUDY ON THE CEPHALO-FACIO-DENTAL RELATIONSHIPS OF NORMAL KOREAN CHILDREN AGED FROM 6 TO 11 YEARS BY SASSOUNI'S ANALYSIS)

  • 유영규
    • 대한치과교정학회지
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    • 제17권2호
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    • pp.165-183
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    • 1987
  • The purpose of this study is to investigate the cephalo-facio-dental relationships in the craniofacial complex and their changes with age, and to use them for diagnostic and treatment purposes in the orthodontics The author studied on the changes of the cephalo-facio-dental relationships, using serial lateral cephalometric roentgenograms of 46 boys and 47 girls aged from 6 to 11 years of normal Korean children Following results were obtained 1 Means and Standard deviation of Korean children were obtained. 2 In the evaluation of the craniofacial vertical proportions, lower anterior face was larger than the upper, and upper posterior face was larger than the lower at all ages 3 The growth change was more prominent in the anterior craniofacial vertical proportion than in the posterior, and growth increment in the upper anterior facial height dimension was larger than m the lower anterior. 4 In the evaluation of the craniofacial horizontal proportion, ANS, Pog, Go and 6 were all situated posterior to their reference ares, and point B was always situated anterior to the arc passing by point A. 5. Anteroposterior growth change was the most prominent in the mandible, and there was no significant difference between the horizontal growth increment in the cranial base and that in the maxilla 6 Growth increment in the horizontal direction was larger in the mandibular apical base than in the maxillary apical base 7 The upper central incisor and the upper first molar were gradually anterior positioned against their reference ares with age increase 8 The length of mandibular corpus was larger than that of cranial base from the seven years old, and the difference was increased as the age increased 9 With age, there was slight difference in the angular relationships formed by craniofacial reference planes and axial inclinations of upper and lower permanent teeth.

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