• Title/Summary/Keyword: Shape Index

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Structural Optimization of a Control Arm with Consideration of Durability Criteria (내구기준을 고려한 컨트롤 암의 구조최적설계)

  • Kim, Jong-Kyu;Park, Young-Chul;Kim, Young-Jun;Lee, Kwon-Hee
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.33 no.11
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    • pp.1225-1232
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    • 2009
  • This study suggests a structural design process for the upper control arm installed at a vehicle. Static strength and durability are the most important responses in the structural design of a control arm. This study considers the static strength in the optimization process. The inertia relief method for FE analysis is utilized to simulate the static loading conditions. According to the classification of structural optimization, the structural design of a control arm is included in the category of shape optimization. In this study, the metamodel technique using the kriging method is adopted to obtain the minimum weight satisfying the strength constraint. Then, the final design is suggested by considering the durability criteria. The durability assessment is obtained by the index of fatigue durability called the SWT (Smith-Watson-Topper) index. The final optimum shape has been proposed by trial and error method.

Nonlinear shape resotration based on selective learning SOFM approach (선택적 SOFM 학습법을 사용한 비선형 형상왜곡 영상의 복원)

  • 한동훈;성효경;최흥문
    • Journal of the Korean Institute of Telematics and Electronics C
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    • v.34C no.1
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    • pp.59-64
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    • 1997
  • By using a selective learnable self-organizing feature map(SOFM) a more practical and generalized mehtod is proposed in which the effective nonlinear shape restoration is possible regardless of the existence of the distortion modelss. Nonlinear mapping relation is extracted from the distorted imate by using the proposed selective learning SOFGM which has the special property of effectively creating spatially organized internal representations and nonlinear relations of various input signals. For the exact extraction of the mapping relations between the distorted image and the original one, we define a disparity index as a proximal nmeasure of the present state to the final idealy trained state of the SOFM, and we used this index to adjust the training of the mapping relations form the weights of the SOFM. Simulations are conducted on various kinds of distorted images with or without distortion models, and the results show that the proposed method is very efficeint very efficient and practical in nonlinear shape restorations.

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Lifetime Performance Index for Weibull Distribution: Estimation and Applications (와이블 분포를 따를 때 수명성능지수의 추정과 활용)

  • Seo, Sun-Keun
    • Journal of Applied Reliability
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    • v.13 no.3
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    • pp.191-206
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    • 2013
  • Application areas for Lifetime Performance Index(LPI), a kind of process capability index to be frequently used as a means of measuring process performance are illustrated with examples. Statistical properties for maximum likelihood and unbiased estimators of LPI are evaluated and discussed under Weibull distribution with known shape parameter. Furthermore, guidelines for selecting an estimator of LPI are also presented.

Effect of Varying Levels of Aflatoxin, Ochratoxin and Their Combinations on the Performance and Egg Quality Characteristics in Laying Hens

  • Verma, J.;Johri, T.S.;Swain, B.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.7
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    • pp.1015-1019
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    • 2003
  • A 50 day feeding trial was conducted with White Leghorn (WL) laying hens, 42 weeks old, to determine if feeding of varying levels of aflatoxin (AF), ochratoxin A (OA) or their combinations has any effect on their performance and egg quality parameters. Feeding of $T_4$, $T_7$, $T_8$, $T_9$ and $T_10$ caused significant reduction in feed intake of hens. Hen day egg productions were significantly reduced at all the levels of toxins except 0.5 ppm of AF. Maximum reduction in egg production was noticed at 2 and 4 ppm of AF and OA, respectively. Average body weight and egg weight were not affected by toxin feeding. The feed efficiency in terms of net feed efficiency and feed consumed per dozen egg produced was significantly reduced at higher levels of both the toxins and their combinations. Feed consumption for production of 1 kg egg mass remained uninfluenced due to aflatoxin feeding whereas significant increase in the value of the same was noticed at 4 ppm level of OA and combination of 1 and 2 ppm of AF and 2 and 4 ppm of OA ($T_9$ and $T_10$), respectively. Various levels of OA (1-4 ppm) and all the combination of two toxins ($T_8$, $T_9$ and $T_10$) significantly altered the shape index of eggs in laying hens. The shell thickness was significantly reduced by higher level of AF (2 ppm), OA (2 and 4 ppm) and their combination. Albumen index, Haugh Unit and yolk index remained unchanged due to incorporation of toxins in the diet. It is concluded that AF, OA either singly or in combination at higher levels could depress the performance in terms of egg production and feed efficiency significantly. The egg quality parameters i.e. shape index and shell thickness were also significantly affected.

Comparison in Weight, Height, Degree of Obesity and Body Mass Index Among Different Methods for Body Shape Classification in School-Age Children (학령기아동의 체형분류법에 따른 체중, 키, 비만도 및 체질량지수 비교)

  • Ahn, Young-Mee;Sohn, Min;Choi, Sun-Ha
    • Journal of Korean Academy of Nursing
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    • v.40 no.6
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    • pp.775-784
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    • 2010
  • Purpose: The study was conducted to describe body shapes of school age children using the degree of obesity index (DOI) and body mass index obesity index classified by the Ministry of Education, Science and Technology (M-BOI) and Seoul Metropolitan Office of Education (S-BOI). Methods: In this cross sectional descriptive study health screening data for school children collected in 2007 was used. Results: Data were analyzed for 2,193 4th-6th grade boys (52%) and girls who attended 4 schools in rural areas. DOI determined that only 44.3% of students had average weight. This proportion was much lower than the results of other methods (74.3-77.6%). All three methods defined girls (51.3-61.8%) as skinnier than boys. Skinny and average body shaped children classified by DOI and obese children classified by S-BOI were heavier and taller and presented higher degrees of obesity (DO) and BMI scores than by other methods. M-BOI and S-BOI presented statistically significant positive correlations with weight, height, DO and BMI, while DOI was not correlated with height. Conclusion: BMI based body shape classifications provide a more rigorous classification of body shape which are favorable for school health professionals with limited resources and policy makers for internationally comparable references.

A Study on the Physical Characteristics of Plus-sized Women, by Age (Plus-size 여성의 연령별 신체 특성에 관한 연구)

  • 하희정;김애린
    • The Research Journal of the Costume Culture
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    • v.11 no.1
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    • pp.153-164
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    • 2003
  • For this study, 148 female adults between the ages of 20 and 60 who satisfied the plus-size judgment criteria took part in this study. Criteria were Rohrer index is higher than 1.5, bust girth larger than 90cm, and RBW(relative body weight) index higher than 110. Using anthropometric measurement values, indirect measurement values, and index values, this study analyzed frequencies, Duncan multiple range, and ANOVA to obtain information on characteristics that determine a representative body shape, by age, 1'3r Plus-sized women. The results are as follows: Physical Characteristics of Pius-Sized Women by Their Age: Women in their 20s md 30s had broader shoulders with smaller waists, with large buttocks and thighs. Among women in their 50s and 60s, body fat level increased significantly in regions such as the chest and abdomen, which made their upper body heavier.

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Body mass Index and Food Habits of Female University Students in Seoul (서울 지역 여대생 체격지수와 식습관 -식품영양전공대학생을 중심으로-)

  • 정남용;최순남
    • Korean journal of food and cookery science
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    • v.18 no.5
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    • pp.505-515
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    • 2002
  • The purpose of this study was to investigate the body mass index and food habits of female university students (nutrition majors) in Seoul. The means of height, weight and BMI were 161.22${\pm}$4.63cm, 52.76${\pm}$6.59kg, and 22.20${\pm}$3.98, respectively. Subjects were divided into 3 groups based on BMI. The ratio of underweight, normal, and overweight students was 25.2%, 56.3%, and 18.5%. respectively. There were significant differences in the recognition rate of body shape and the way to maintain health by BMI. And self satisfaction rate of body shape was significantly higher in underweight subjects compared with others. There was no significant difference in the rate of activity and exercise, food behavior, intake frequency of various foods, intake of convenience food and carbonated drink according to BMI. Weight and body fat of subjects had a significant correlation with BMI. and height, frequency of taking food, frequency of meals, food behavior, intake food, health and exercise consciousness rate showed no correlation with BMI.

Numerical Study on the Flow Characteristics with a Vane-type Static Mixer in the Diesel Exhaust Systems (Vane-type Static Mixer에 의한 디젤차량 배기관 내의 유동 특성에 관한 연구)

  • Kang, Kyoung-Nam;Kim, Man-Young
    • Transactions of the Korean Society of Automotive Engineers
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    • v.20 no.5
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    • pp.36-43
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    • 2012
  • In this work the mixing and flow characteristics of a vane-type static mixer were investigated numerically for the reduction of NOx in the SCR-system of the diesel engines. The mixer was located in the 57 times pipe diameter away from the inlet. The analysis were performed by changing such various parameters as vane shape, angles, blockage ratio and location of the vane. The flow structure through the mixer was characterized by uniformity index and pressure drop. The results show that uniformity index and pressure coefficient are substantially influenced by the vane shape, angle, blockage ratio and position of the vane of the mixer.

A Study on Optimal Shape-Size Index Extraction for Classification of High Resolution Satellite Imagery (고해상도 영상의 분류결과 개선을 위한 최적의 Shape-Size Index 추출에 관한 연구)

  • Han, You-Kyung;Kim, Hye-Jin;Choi, Jae-Wan;Kim, Yong-Il
    • Korean Journal of Remote Sensing
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    • v.25 no.2
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    • pp.145-154
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    • 2009
  • High spatial resolution satellite image classification has a limitation when only using the spectral information due to the complex spatial arrangement of features and spectral heterogeneity within each class. Therefore, the extraction of the spatial information is one of the most important steps in high resolution satellite image classification. This study proposes a new spatial feature extraction method, named SSI(Shape-Size Index). SSI uses a simple region-growing based image segmentation and allocates spatial property value in each segment. The extracted feature is integrated with spectral bands to improve overall classification accuracy. The classification is achieved by applying a SVM(Support Vector Machines) classifier. In order to evaluate the proposed feature extraction method, KOMPSAT-2 and QuickBird-2 data are used for experiments. It is demonstrated that proposed SSI algorithm leads to a notable increase in classification accuracy.

The Analysis Method of Landscape Fragmentation using Normalized Difference Vegetation Index (식생지수에 의한 경관파편화의 해석기법)

  • Jeong, Jong-Chul
    • Journal of the Korean Association of Geographic Information Studies
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    • v.2 no.3
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    • pp.16-22
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    • 1999
  • The various spatial structure of biological habitat has tighten relationship with biodiversity. Due to increasing of population, development of agriculture and urban structure, various change of landscape has became these days. These change of landscape has raised the decrease of habitat and landscape fragmentation. This paper summarizes research to analysis vegetation index according to P/A ratio, Shape Index, and Fractal dimension using Landsat Thematic Mapper(TM). The analysis of landscape fragmentation using NDVI(Normalized Difference Vegetation Index) 0.5~1 has the most profitable for detection of vegetation fragmentation. The analysis of vegetation index of Seoul and Kyunggi province has also showed that Fractal dimension has the most fragmentation index. In near future, time series analysis is needed for fragmentation of vegetation on the same area, and for various landuse of fragmentation analysis. These researches were carried out for preservation strategy of vegetation and biodiversity.

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