• 제목/요약/키워드: Shape Index

검색결과 882건 처리시간 0.028초

특징점들의 적응적 선택에 근거한 B-spline 곡선근사 (B-spline Curve Approximation Based on Adaptive Selection of Dominant Points)

  • 이주행;박형준
    • 한국CDE학회논문집
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    • 제11권1호
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    • pp.1-10
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    • 2006
  • This paper addresses B-spline curve approximation of a set of ordered points to a specified toterance. The important issue in this problem is to reduce the number of control points while keeping the desired accuracy in the resulting B-spline curve. In this paper we propose a new method for error-bounded B-spline curve approximation based on adaptive selection of dominant points. The method first selects from the given points initial dominant points that govern the overall shape of the point set. It then computes a knot vector using the dominant points and performs B-spline curve fitting to all the given points. If the fitted B-spline curve cannot approximate the points within the tolerance, the method selects more points as dominant points and repeats the curve fitting process. The knots are determined in each step by averaging the parameters of the dominant points. The resulting curve is a piecewise B-spline curve of order (degree+1) p with $C^{(p-2)}$ continuity at each knot. The shape index of a point set is introduced to facilitate the dominant point selection during the iterative curve fitting process. Compared with previous methods for error-bounded B-spline curve approximation, the proposed method requires much less control points to approximate the given point set with the desired shape fidelity. Some experimental results demonstrate its usefulness and quality.

한국 재래닭의 난형에 관한 연구

  • 상병돈;최철환;김학규;나재천;김상호;장병귀;서옥석;이상진
    • 한국가금학회:학술대회논문집
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    • 한국가금학회 2004년도 제21차 정기총회 및 학술발표회
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    • pp.99-100
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    • 2004
  • 한국 재래닭의 각 계통별 세대간 계란의 장경, 단경 및 난형지수는 각각 53.0$\pm$0.6~55.6$\pm$0.8 mm, 39.1$\pm$0.8~40.9$\pm$0.2 mm 및 72.7$\pm$1.5~75.9$\pm$0.5이었고 회귀방정식에 의한 회귀계수로 표현된 능력변화 추세를 보면 적갈색, 황갈색, 회갈색, 흑색 및 백색 계통의 계란 장경은 각각 -0.01, 0.20, -0.02, -0.01 및 0.03 mm, 단경은 각각 0.10, 0.48, 0.52, 0.25 및 0.25 mm, 난형지수는 0.19, 0.62, 1.00, 0.32 및 0.33이었다.

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형태안정성 PCM: 잠열저장을 위한 Polypropylene과 n-Eicosane으로 구성된 고화젤의 제조 및 특성 (Shape-Stabilized Phase Change Materials: Preparation and Properties of Frozen Gels from Polypropylene and n-Eicosane for Latent Heat Storage)

  • 손태원;임학상;김태훈;고재왕
    • 폴리머
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    • 제34권3호
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    • pp.261-268
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    • 2010
  • 본 연구에서는 상전이 온도가 36 $^{\circ}C$인 n-eicosnae을 열가소성 폴리올레핀 고분자인 폴리프로필렌과 블렌드하였으며, 또한 최근의 형태안정성 PCM(SSPCM)의 연구검토를 통하여 폴리프로필렌과 n-eicosnae의 특성과 잠열저장체로서의 적용 가능성을 확인하였다. 상전이 온도가 36 $^{\circ}C$인 n-eicosane과 폴리프로필렌을 멜팅방법과 흡수방법을 이용하여 시료를 제조하였다. 제조된 형태안정성 PCM(SSPCM)을 DSC, WAXD, FTIR spectroscopy, ARES로 분석결과 형태안정성, 열용량의 향상을 확인하였다.

Effect of Processing Method on Change of Water Soluble Dietary Fiber of Fagopyrum tataricum

  • Kim, Dong-Eun;Lee, Beom-Goo;Park, Cheol-Ho;Kang, Wie-Soo
    • Agricultural and Biosystems Engineering
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    • 제6권2호
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    • pp.70-76
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    • 2005
  • Seed, stem and sprout of F. tataricum were separately milled using the ultra fine mill under the same condition to investigate the effect of roasting or extruding on the particle size, microstructure and water solubility of dietary fiber. The mean particle size of MR (roasting) is increased in stem and sprout, and that of ME (extruding) is increased in seed, compared to that of control. The microscopic views of seed show that control has the spherical shape but ME the larger and irregular shape, and those of stem and sprout show that control has the needle like shape but ME more rounded shape. Water solubility index of ME is much higher than that of control or MR in seed, stem and sprout. It shows that seed, stem and sprout are damaged more in extruding than in roasting, and the starch and cell wall structure must be destroyed to change the water insoluble dietary fiber into the water soluble dietary fiber.

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경남지역 일부 중학생들의 체형 선호도 조사 (The Perception of Desirable Body Shape in Some Middle School Students of Gyeongnam Area)

  • 김성희
    • 한국식품영양과학회지
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    • 제27권5호
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    • pp.1007-1014
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    • 1998
  • A questionnaire was administered to 850 middle school students in Jinju city and Hamyang province to asses their body shape preferences. Their mean current BMI(body mass index, Kg/㎡) in males(19.23±2.77) was higher than that in females(18.61±2.59). On the other hand, significant differences in BMI were not found between areas. The perceived desired weights for their current height were about+0.22kg(males) and -4.32kg(females) of their actual weights. In spite of the average weight group, many wished to lose weight because of their tendency to perceive themselves as overweight, especially among rural females. Their ideal body shape as perceived by them were 'normal' in males and 'a bit thin' in females, independent of the areas. As for the 'contentment' regarding their current weight and health, the most satisfied group in males were estimated average weight and slightly overweight group, respectively. While, the most satisfied group in females were estimated slightly underweight and overweight group, respectively. Their extreme slim-body preference might have its root in the lack of proper understanding of what the 'standard' body weight was.

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사두증 환자를 위한 맞춤형 헬멧 몰드 디자인 시스템 개발 (Development of a Customized Helmet Design System for Patients with Plagiocephaly)

  • 강영훈;박혜련;김성민
    • 한국의류산업학회지
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    • 제24권4호
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    • pp.443-450
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    • 2022
  • This study developed a three-dimensional helmet mold design software that can design helmets for treating the infant plagiocephaly (flat head syndrome) using three-dimensional head scan data. For this, the three-dimensional head data of sixth SizeKorea body measurement project as well as the data produced by a head modeling software were used to prepare the head shape data of plagiocephaly patients. A total of 14 landmarks and 10 dimensions of heads required for helmet mold shape design and plagiocephaly diagnosis were automatically measured using an anthropometric analysis software. Using the software developed in this study, plagiocephaly can be diagnosed not only visually by three-dimensional head data visualization but also quantitatively by calculating the medically defined indices such as cranial index, which measures the proportions of the head, and the cranial vault asymmetry index, which measures the asymmetry of the head. The basic shape of the helmet mold was automatically generated based on the head scan data. Additionally, it is possible to fine tune the shape of the mold to reflect individual characteristics by using a free form deformation technique. Finally, the designed helmet mold was converted into the data that can be printed on a three-dimensional printer for generating the actual prototype.

정상체중과 과체중 여대생을 대상으로 컵의 형태에 따른 인지량의 차이에 관한 연구 (Difference in Volume Perception according to Cup Shape in Normal Weight and Overweight Female College Students)

  • 이명옥;장은재
    • 대한영양사협회학술지
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    • 제20권1호
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    • pp.63-69
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    • 2014
  • The volume perception of water according to cup shape was examined in female college students divided into a normal weight group (<23 body mass index, n=51) and an overweight group (${\geq}$23 body mass index, n=48). The perceived water volume was recorded by participants after they observed the water volume in cups with different shape (highball and tumbler) and with different base height (high base and low base), which contained the same amount of water (150 ml). The normal weight group perceived a water volume of 238.5 ml (highball) and 201.6 ml (tumbler) for the high base cups. The overweight group perceived a volume of 245.6 ml (highball) and 188.8 ml (tumbler). For the low base cups, the normal weight group perceived a water volume of 207.8 ml (highball) and 104.1 ml (tumbler). The overweight group perceived a volume of 202.2 ml (highball) and 100.4 ml (tumbler). Both the normal weight and overweight groups perceived significantly more liquid in the highball cups compared to the tumbler cups. In addition, both groups perceived significantly more liquid in the high base cups compared to the low base cups. However, there were no significant differences in the estimated variance of perceived volume between the normal weight and overweight groups according to the cup shape and cup base height. In conclusion, cup shape and base height potentially affects volume perception. Therefore, modifying cup shape may be used in a weight control program to help control caloric beverage consumption.

The effects of body mass index and body shape perceptions of South Korean adults on weight control behaviors; Correlation with quality of sleep and residence of place

  • Kang, Nam E;Kim, Seung Ju;Oh, Yoon Sin;Jang, Se-Eun
    • Nutrition Research and Practice
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    • 제14권2호
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    • pp.160-166
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    • 2020
  • BACKGROUND/OBJECTIVES: The obese population is rapidly increasing because of reduced physical activity and a Westernized diet; consequently, various chronic diseases are more prevalent. With the increasing interest in body shape and appearance, research on body shape perceptions and accompanying weight control behaviors are needed for healthy weight management. SUBJECTS/METHODS: A cross-sectional survey was conducted on randomly selected 536 (209 men and 327 women) aged 20 to 65 years. Body mass index (BMI), body-shape perception, weight control behavior, quality of sleep, and place of residence were collected using self-reported questionnaires. Multivariable logistic regression analysis was conducted using complex design in each groups. Collected data were analyzed using the SAS 9.4 statistical package, and the significance level was set at P < 0.05. RESULTS: When these two variables were divided into four groups, they were found to influence dieting attempts. People with abnormal weights who were dissatisfied with their body shapes attempted dieting 5.23 times more than those with healthy weights and satisfaction with their body shapes. Further, those with normal weights but dissatisfaction with their bodies attempted dieting 4.45 times more than those who were satisfied with their shapes. Subjects in their 20s attempted dieting 2.53 times more than those in their 30s and 40s, and female subjects attempted dieting 2.24 times more than male subjects. CONCLUSIONS: A correct perception of one's shape can be an important factor for dietary behavior, as body shape perceptions and dieting attempts are strongly related. Additionally, healthy weight management and nutrition education are important elements to incorporate into a weight control program aimed at preventing excessive weight control behaviors and promoting correct perceptions of body shape.

돔 형상 변화에 따른 복합재 압력용기의 구조 거동 예측 (The Prediction of Structural Behavior for Composite Pressure Vessel with Changed Dome Shape)

  • 황태경;박재범;김형근;도영대
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2008년도 제31회 추계학술대회논문집
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    • pp.288-292
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    • 2008
  • 동일 보스 오프닝에 대해 여러 형상의 돔을 설계할 수 있는 복합재 압력용기용 형상 식이 제시되었고, 이러한 돔 형상 변화에 따른 복합재 압력용기의 성능(파열압력*내부용적/복합재무게) 변화를 유한 요소 응력해석과 시험을 통해 규명하였다. 해석을 통해 예측한 돔 형상 변화에 따른 압력용기의 파열압력이 시험 결과와 좋은 일치를 나타내었다. 전반적으로 돔 형상이 낮아짐에 따라 압력용기 내부 용적이 증가하였으나, 파열 압력은 저하되는 현상을 나타내었다. 보스 오프닝 비(${\rho}_o$)가 0.54 이상인 경우, 돔 형상이 낮아짐에 따라 파열 압력이 저하되어 성능 저하가 나타났다. 그러나 보스 오프닝 비(${\rho}_o$)가 0.34이하 경우 돔 형상 변화에 따른 파열 압력 저하가 크지 않음으로 성능의 큰 변화가 없었다.

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경사 구조물이 침전지내 수리거동 Index에 미치는 영향 (A Study on the Effect of the Inclined Structure on the Hydraulic Behavior Index within Sedimentation basin)

  • 임성호;황준식;박노석;김성수;임경호
    • 상하수도학회지
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    • 제23권5호
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    • pp.517-526
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    • 2009
  • This research has been conducted to investigate the characteristics of hydraulic behavior within the PAC contactor, the rectangular shape sedimentation basin without inclined tube and the other one with inclined tube those are parts of demonstration plants(capacity : $2,000m^3/d$) in Korea Institute of Water and Environment. As results of tracer tests, the flow within PAC contactor was evaluated to divided into plug flow and dead space distinctly, and characteristics of dead space was close to that of CSTR(Complete/continuous Stirred Tank Reactor). Also, considering Reynolds number, Froude number, Morill, Modal, NCSTR Inex and plug flow/mixed flow fraction, in the case of the rectangular shape sedimentation basin without inclined tube, the characteristics of flow pattern was close to CSTR. On the other hand, in the case of the basin with inclined tube, the region of CSTR decreased precisely compared with the case of no-tube. Until now we have recognized that the inclined hydraulic structure just reduces the surface loading rate within a sedimentation basin. Actually besides, the inclined structure have an important effect on the hydraulic behavior within the basin.