• Title/Summary/Keyword: different shapes

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Performance Comparison of Dish Solar Collector With Mirror Arrays & Receiver Shapes (반사경 배치와 흡수기 형상에 따른 접시형 고온 태양열 시스템 성능비교)

  • Ma, Dae-Sung;Kim, Yong;Seo, Tae-Beom
    • Journal of the Korean Solar Energy Society
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    • v.27 no.1
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    • pp.29-38
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    • 2007
  • In order to analyze the performance comparison of dish solar collector with mirror arrays and receiver shapes, the radiative heat flux distribution inside the cavity receiver is numerically investigated. The solar irradiation reflected by dish solar collector is traced using the Monte-Carlo method. Five different dish solar collectors and three different cavity receivers are considered. A parabolic-shaped perfect mirror of which diameter is 1.5 m is considered as a reference dish solar collector and four different arrays of twelve identical parabolic-shaped mirror facets of which diameter are 0.4 m are used. Their reflecting areas, which are $1.5\;m^2$, are the same. Three different cavity receiver shapes are dome, conical, and cylindrical. In addition, the radiative properties of the concentrating surfaces can vary the thermal performance of the cavity receiver so that variation of the surface reflectivity of each mirror is considered. Based on the calculation, the design information of dish solar collector for producing the electric power can be obtained. The results show that the dome type has the best performance in receiver shapes and the 2AND4 INLINE has the best performance in mirror arrays except perfect mirror.

Effect of Hole Shapes, Orientation And Hole Arrangements On Film Cooling Effectiveness

  • Jindal, Prakhar;Roy, A.K.;Sharma, R.P.
    • International Journal of Aeronautical and Space Sciences
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    • v.17 no.3
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    • pp.341-351
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    • 2016
  • In this present work, the effect of hole shapes, orientation and hole arrangements on film cooling effectiveness has been carried out. For this work a flat plate has been considered for the computational model. Computational analysis of film cooling effectiveness using different hole shapes with no streamwise inclination has been carried out. Initially, the model with an inclination of $30^{\circ}$ has been verified with the experimental data. The validation results are well in agreement with the results taken from literature. Five different hole shapes viz. Cylindrical, Elliptic, Triangular, Semi-Cylindrical and Semi-Elliptic have been compared and validated over a wide range of blowing ratios. The blowing ratios ranged from 0.67 to 1.67. Later, orientation of holes have also been varied along with the number of rows and hole arrangements in rows. The performance of film cooling scheme has been given in terms of centerline and laterally averaged adiabatic effectiveness. Semi-elliptic hole utilizes half of the mass flow as in other hole shapes and gives nominal values of effectiveness. The triangular hole geometry shows higher values of effectiveness than other hole geometries. But when compared on the basis of effectiveness and coolant mass consumption, Semi-elliptic hole came out to give best results.

A Study of Lower Body Shapes of Plus-sized Women to Index (지수치를 이용한 Plus-size 여성의 하반신 체형 연구)

  • Ha, Hee-Jung;Sung, Ok-Jin
    • The Research Journal of the Costume Culture
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    • v.13 no.1
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    • pp.6-17
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    • 2005
  • The purpose of this research is to define low body shapes of Plus-sized women at ages between 21 and 69 whose satisfied the Plus-sized judgment criteria took part in this study. This research also classifies different body types, and provides basic data for designing skirt's and slacks' prototypes according to each body type. Based on factor analysis of the measured data, seven key factors are grouped. And four different body types are classified based on the cluster analysis using factor marks. Type 1 refers to those who are tall in stature and balanced. This body type is characterized by trapezoid body shape when looked from the front, and slim the abdomen, bulge the belly and flat the buttocks when looked from the side. Type 2 refers to short and an obese body shapes, with trapezoid front and bulge abdomen and belly and flat the buttocks. Type 3 refers to those who are of medium height and long-legged body shapes, with rectangular front, protruding belly and buttocks. Type 4 refers to obese body shapes, with rectangular front, protruding abdomen and belly, flat the buttocks. 9 items are available to judge Plus-sized women's low body types and the hit ratio is 93.5%.

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3D model for korean-japanese sign language image communication (한-일 수화 영상통신을 위한 3차원 모델)

  • ;;Yoshinao Aoki
    • Proceedings of the IEEK Conference
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    • 1998.06a
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    • pp.929-932
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    • 1998
  • In this paper we propose a method of representing emotional experessions and lip shapes for sign language communication using 3-dimensional model. At first we employ the action units (AU) of facial action coding system(FACS) to display all shapes. Then we define 11 basic lip shapes and sounding times of each components in a syllable in order to synthesize the lip shapes more precisely for korean characters. Experimental results show that the proposed method could be used efficiently for the sign language image communication between different languages.

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Study of classification period between Araliae Continentalis Radix and Osterici Radix

  • Kang, Suk-Hoon;Kang, Ok-Hwa;Kwon, Dong-Yeul
    • Journal of Evidence-Based Herbal Medicine
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    • v.2 no.1
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    • pp.13-18
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    • 2009
  • The aim of this study was to find out the time when the Araliae Continentalis Radix and Osterici Radix were classified into different divisions as the period were not known to oriental medical science in Korea. It could be said that the Araliae Continentalis Radix and Osterici Radix had been recognized the different shapes since Sui-Tang eras and they had been differently used in their shapes and effects as separated medical plants since Song-Yuan eras. This thesis also presented the effects and shapes of Araliae Continentalis Radix and Osterici Radix as well as showed prescriptions and the uses of them in each dynasty of China.

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Characteristics of AE Signals of Matrix Cracks in Composites Due to the Different Specimen Shapes (시편 형상에 따른 복합재료의 모재균열 신호특성)

  • 방형준;박상욱;김천곤;홍창선
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2002.05a
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    • pp.39-43
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    • 2002
  • As the concept of the smart structure, monitoring of acoustic emission (AE) can be applied to inspect the fracture of the entire structure in operating condition using built-in sensors. The objective of this study is to find the characteristics of matrix crack signals in composites due to the different specimen shapes. To detect matrix crack signals, we performed tensile tests by changing the thickness, width and length of the specimen. For the quantitative evaluation, time frequency analysis such as short-time Fourier transform (STFT) was used to characterize the matrix crack signals from PZT sensor. The experimental result shows the distinctive signal features in frequency domain due to the different specimen shapes.

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Energy Absorbing Characteristics of Thin-Walled Members for Vehicles Having Various Section Shapes (차체구조용 박육부재의 단면형상변화에 따른 에너지흡수 특성)

  • 차천석;정진오;이길성;백경윤;양인영
    • Journal of the Korean Society for Precision Engineering
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    • v.20 no.10
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    • pp.177-182
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    • 2003
  • The front-end side members of automobiles absorb most of the energy in a case of front-end collision. The front-end side members are required to have a high stiffness together with easiness to collapse sequentially to absorb more impact energy. The axial static collapse test (5mm/min) was conducted by using UTM for form different types of members which have different cross section shapes; single hat, single cap, double cap, and double hat. The single hat shaped section member has the typical standard section, which the double hat shape section has a symmetry in the center to have more stiffness. As a result of the test, the energy absorbing characteristic was analyzed for different section shapes. It turned out that the change of section shape influence the absorbing energy, the mean collapse load and the maximum collapse load, and the relation between the change of section shape and the collapse mode.

Comparison of Satisfaction with the Size of Ready-made Clothing between Normal and Obese Women in the Busan and Gyeongnam Area (부산.경남지역 표준여성과 비만여성의 기성복 치수 만족도 비교)

  • Oh, Young-Soon;Lee, Jeong-Ran
    • The Korean Journal of Community Living Science
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    • v.19 no.1
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    • pp.21-30
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    • 2008
  • This study conducted a survey to compare the size of ready-made clothes for different body shapes and body sizes, and to discover the differences in satisfaction with the size of ready-made clothes. The subjects were women in their 208 and 308 from Busan and Gyeongnam. The women were classified into groups: normal weight, overweight, and obese, using the Body Mass Index (BMI). The comparison of the body size showed a significant difference among the shapes; the average BMI in overweight women was 24.2 while that of obese women was 27.6. For the clothing size for each body shape, obese women most often wore size 77 and size 88, regardless of the sizes of upper and lower garments. The size consistency of upper and lower garments was the lowest in obese women. However, in most of the shapes, women tended to choose larger-sizes for lower garments than for upper ones. The more obese the subject, the less inclined they were to wear garments for their real body size. Satisfaction with the clothing size was significantly different between body shapes; the more obese, the lower the level of satisfaction with the size. As well, satisfaction with the fit of clothing at certain parts was shown to be low especially in the bust measurement, shoulder width, upper garment length, crotch length, and thigh circumference. When surveyed about the use of alterations for different body shapes, the results were that over 65% of subjects did not alter upper garments regardless of their body shape. Comparatively, 68% or above of all body shapes did do alterations to lower garments for example, the length of pants or skirts.

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Damage detection in steel structures using expanded rotational component of mode shapes via linking MATLAB and OpenSees

  • Toorang, Zahra;Bahar, Omid;Elahi, Fariborz Nateghi
    • Earthquakes and Structures
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    • v.22 no.1
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    • pp.1-13
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    • 2022
  • When a building suffers damages under moderate to severe loading condition, its physical properties such as damping and stiffness parameters will change. There are different practical methods besides various numerical procedures that have successfully detected a range of these changes. Almost all the previous proposed methods used to work with translational components of mode shapes, probably because extracting these components is more common in vibrational tests. This study set out to investigate the influence of using both rotational and translational components of mode shapes, in detecting damages in 3-D steel structures elements. Three different sets of measured components of mode shapes are examined: translational, rotational, and also rotational/translational components in all joints. In order to validate our assumptions two different steel frames with three damage scenarios are considered. An iterative model updating program is developed in the MATLAB software that uses the OpenSees as its finite element analysis engine. Extensive analysis shows that employing rotational components results in more precise prediction of damage location and its intensity. Since measuring rotational components of mode shapes still is not very convenient, modal dynamic expansion technique is applied to generate rotational components from measured translational ones. The findings indicated that the developed model updating program is really efficient in damage detection even with generated data and considering noise effects. Moreover, methods which use rotational components of mode shapes can predict damage's location and its intensity more precisely than the ones which only work with translational data.

Analysis of Shapes of Bending and Draping by the Model Rule (닮음 법칙에 의한 굽힘 및 드레이프 형상의 해석)

  • 서정권;이정욱
    • Journal of the Korean Society of Clothing and Textiles
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    • v.20 no.6
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    • pp.1116-1124
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    • 1996
  • The factors to presume the shapes of bending and draping were examined in this study, by applying the similar phenomenon and theory of analysis. The findings were as followings: 1. The value of deflection angle (f) of deflection curve were almost consistent with those of K number and the shapes of deflection curve were congruent, under the condition of that the values of EI/w are almost similar and the lengths of samples are consistent. 2. The values of drape area, drape coefficient, mean of deflection angle, and $\pi$ number were consistently estimated and the shapes of drape were almost the same, under the condition of that the values of EI/w are similar and the diameter of samples are consistent. 3. In using the samples with different values of EI/w, scale factor, kl, was obtained from the formula, the shapes of bending of the referent samples and compsactive smaples was geometrically similar, which the lengths of samples were 1,1'and were satisfied with the formula, hi: L'11, and their $\pi$ number were also consistent. 4. In applying the samples with different values of Rllw, scale factor (kl) was obtained and then, when semidiameter of samples was adjusted to be satisfied with the formula, k1=L/L, the shapes of draping of referent samples and comparative samples were geometrically similar. Furthermore, their $\pi$ number was also consistent. 5. The shares of bending and draping could be changed in terms of three factors such as the lengths of samples, bending ridigity, and weigths per unit area. $\pi$ number was obtained from theory of similar phenomenon, which was index to presume shapes of bending and the shapes of draping getting from the three factors.

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