• Title/Summary/Keyword: different shapes

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Charateristics of Wake Flow in a Flat Plate Blade Having TS and TP Cutting (평판익 후연의 형상에 따른 후류 특성)

  • Jang, Choon-Man;Ahmad, Imteyaz;Kim, Kwang-Yong
    • 유체기계공업학회:학술대회논문집
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    • 2004.12a
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    • pp.452-455
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    • 2004
  • The influence of wake flow on a flat-plate blade having different shapes near the hailing edge has been investigated in this paper. Two different shapes near the trailing edge namely the pressure surface cutting (TP) and the suction surface cutting (TS) have been used. The calculation has been performed for two different angles of attack (a =10 and 15 degree) in both the cases. RANS equations have been solved using SST-model as a turbulence closure. Cp and CL values obtained for TS are higher compared to those obtained for TP. Also, the vorticity distribution obtained in case of TS is stronger as compared to that obtained in the case of TP The Karmann Vortex is observed in both the cases but it is more clear in TS case. It is found that in the case of TS, flow separation does not occur upto the trailing edge on both the suction and the pressure sides of the blade while in the case of TP, the flow separateson the pressure surface near the trailing edge of the flat-plate blade.

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The Role of Modeling in Prosthetics Make-up (보철분장에 있어 모델링의 역할)

  • Lee, Hwa-Jin
    • Journal of the Korean Society of Fashion and Beauty
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    • v.2 no.3 s.3
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    • pp.60-67
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    • 2004
  • Representing all the parts of human body visible to fit into the script, it can be told that real make-up has been done. Based on the point of view. it will be different from others. To become the beautiful, beauty make-up has to be done, however, to be someone described in the script or any other factions after analyzing characters of being represented, special make-up fits into that category. In the special make-up, there are two different pins: one is 2 dimension make-up which is describing images using dots, lines and colors and other is 3 dimension which will include necessary shapes to figure. Even though there seems to be different between modern technologies and handy work, since accurate measures and graphics have to be used to make perfect character describes in the script, more investments and studies than before have to be made. Real attraction of 3 dimension make-up is building up the images and shapes using unseen abstract images having analyzing characters. It will be decided in the working process called modeling. As having distinguished this part from other make-ups as named prosthetics make-up, proposing means and measures of prosthetics make-up will actually help the others who are studying make-up.

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Micelle Studies of Dodecyltrimethylammonium Bromide in Water as Probed by Benzene: Effect on Shapes and Sizes of Micelles

  • Yoon Seob Lee;Kyu Whan Woo
    • Bulletin of the Korean Chemical Society
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    • v.14 no.5
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    • pp.599-602
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    • 1993
  • Micellization process of dodecyltrimethylammonium bromide (DTAB) was studied by using the aromatic probe (benzene) which dissolved in aqueous DTAB solutions. Proton NMR chemical shift measurements of DTAB and DTAB-benzene system showed that benzene molecules solubilized near the micelle-water interface and that the solubilization sites within the micelles are different as the DTAB concentration is passing through 32.0 mM (hereafter we refer this concentration as the second CMC). The change of solubilization sites is also confirmed by abrupt changes of the chemical shifts and relaxation rates of benzene protons in DATB-benzene system at this concentration. It was revealed from the electrical conductivity and viscosity measurements that the solubilization of benzene caused the DTAB micelles to swell out and that the micelles prepared after the second CMC had a greater swelling effect than those prepared before the second CMC. The transition point which reflects the saturation of benzene molecules on the solubilization sites of micelles was observed at one benzene/micellized DTAB mole ratio from the electrical conductivity measurements. Along the different concentration of DTAB solution, this transition point is appeared clearly after the second CMC. From these results it is suggested that the shapes and/or sizes of DTAB micelles of the spherical micelle region prepared after the second CMC are different from those prepared before the second CMC.

Estimation and Comparative Analysis on the Distribution Functions of Air and Water Temperatures in Korean Coastal Seas (우리나라 연안의 기온과 수온 분포함수 추정 및 비교평가)

  • Cho, Hong-Yeon;Jeong, Shin-Taek
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.28 no.3
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    • pp.171-176
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    • 2016
  • The distribution shapes of air and water temperatures are basic and essential information, which determine the frequency patterns of their occurrence. It is also very useful to understand the changes in long-term air and water temperatures with respect to climate change. The typical distribution shapes of air and water temperatures cannot be well fitted using widely used/accepted normal distributions because their shapes show multimodal distributions. In this study, Gaussian mixture distributions and kernel distributions are suggested as the more suitable models to fit their distribution shapes. Based on the results, the tail shape exhibits different patterns. The tail is long in higher temperature regions of water temperature distribution and in lower temperature regions of air temperature distribution. These types of shape comparisons can be useful to identify the patterns of long-term air and water temperature changes and the relationship between air and water temperatures. It is nearly impossible to identify change patterns using only mean-temperatures and normal distributions.

Analysis of Breast Shapes through the Utilization of 3D Scan Data: A Focus on Women in the Early to Late 30s (3차원 데이터를 활용한 유방유형별 형태 분석: 30대 여성을 중심으로)

  • Kim, Ji Min;Kim, Hyo Sook
    • Human Ecology Research
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    • v.52 no.5
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    • pp.509-518
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    • 2014
  • This study strives to analyze the characteristics of and changes in breast shapes of women in their 30s, whose bodies start to age and whose breasts experience changes due to internal and external factors such as pregnancy, childbearing, and breast-feeding. The analysis of the indirect breast measurements for each age group (early, mid, and late 30s) demonstrates that the volume of the breasts increases proportionally with age, the breasts lose their firmness, and the nipples start to point downwards rather than to the sides. The breast shapes experience more significant changes vertically than horizontally as the breasts start to sag downwards. The composition factors of the breasts have been classified into five factors: the level of volume in the breasts and the surrounding area, the degree of sagging in the breasts, the position and vertical width of the breasts, the volume of the breasts, and the degree of width between the breasts. The breasts have been categorized into three different shapes. Breast Shape I (32.56%) appeared most frequently among women in their mid 30s, and this shape falls into the category of Sagging I, which is one of the six breast types that have been classified by the Japanese Wacoal Research Center, in addition to Korean size 80A. Breast Shape II (38.76%) appeared most frequently among women in their mid 30s, and this shape has been categorized as flat with its size being 70A. Breast Shape III (28.68%) appeared most frequently among women in their early 30s with a conical shape and size 75A.

Synthesis of vertically aligned silicon nanowires with tunable irregular shapes using nanosphere lithography

  • Gu, Ja-Hun;Lee, Tae-Yun
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2012.05a
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    • pp.88.1-88.1
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    • 2012
  • Silicon nanowires (SiNWs), due to their unusual quantum-confinement effects that lead to superior electrical and optical properties compared to those of the bulk silicon, have been widely researched as a potential building block in a variety of novel electronic devices. The conventional means for the synthesis of SiNWs has been the vapor-liquid-solid method using chemical vapor deposition; however, this method is time consuming, environmentally unfriendly, and do not support vertical growth. As an alternate, the electroless etching method has been proposed, which uses metal catalysts contained in aqueous hydrofluoric acids (HF) for vertically etching the bulk silicon substrate. This new method can support large-area growth in a short time, and vertically aligned SiNWs with high aspect ratio can be readily synthesized with excellent reproducibility. Nonetheless, there still are rooms for improvement such as the poor surface characteristics that lead to degradation in electrical performance, and non-uniformity of the diameter and shapes of the synthesized SiNWs. Here, we report a facile method of SiNWs synthesis having uniform sizes, diameters, and shapes, which may be other than just cylindrical shapes using a modified nanosphere lithography technique. The diameters of the polystyrene nanospheres can be adjustable through varying the time of O2 plasma treatment, which serve as a mask template for metal deposition on a silicon substrate. After the removal of the nanospheres, SiNWs having the exact same shape as the mask are synthesized using wet etching technique in a solution of HF, hydrogen peroxide, and deionized water. Different electrical and optical characteristics were obtained according to the shapes and sizes of the SiNWs, which implies that they can serve specific purposes according to their types.

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Investigation on deck-stay interaction of cable-stayed bridges with appropriate initial shapes

  • Liu, Ming-Yi;Lin, Li-Chin;Wang, Pao-Hsii
    • Structural Engineering and Mechanics
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    • v.43 no.5
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    • pp.691-709
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    • 2012
  • This paper provides a variety of viewpoints to illustrate the mechanism of the deck-stay interaction with the appropriate initial shapes of cable-stayed bridges. Based on the smooth and convergent bridge shapes obtained by the initial shape analysis, the one-element cable system (OECS) and multi-element cable system (MECS) models of the Kao Ping Hsi Bridge in Taiwan are developed to verify the applicability of the analytical model and numerical formulation from the field observations in the authors' previous work. For this purpose, the modal analysis of the two finite element models are conducted to calculate the natural frequency and normalized mode shape of the individual modes of the bridge. The modal coupling assessment is also performed to obtain the generalized mass ratios among the structural components for each mode of the bridge. The findings indicate that the coupled modes are attributed to the frequency loci veering and mode localization when the "pure" deck-tower frequency and the "pure" stay cable frequency approach one another, implying that the mode shapes of such coupled modes are simply different from those of the deck-tower system or stay cables alone. The distribution of the generalized mass ratios between the deck-tower system and stay cables are useful indices for quantitatively assessing the degree of coupling for each mode. These results are demonstrated to fully understand the mechanism of the deck-stay interaction with the appropriate initial shapes of cable-stayed bridges.

Effects of macroporosity and double porosity on noise control of acoustic cavity

  • Sujatha, C.;Kore, Shantanu S.
    • Advances in aircraft and spacecraft science
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    • v.3 no.3
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    • pp.351-366
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    • 2016
  • Macroperforations improve the sound absorption performance of porous materials in acoustic cavities and in waveguides. In an acoustic cavity, enhanced noise reduction is achieved using porous materials having macroperforations. Double porosity materials are obtained by filling these macroperforations with different poroelastic materials having distinct physical properties. The locations of macroperforations in porous layers can be chosen based on cavity mode shapes. In this paper, the effect of variation of macroporosity and double porosity in porous materials on noise reduction in an acoustic cavity is presented. This analysis is done keeping each perforation size constant. Macroporosity of a porous material is the fraction of area covered by macro holes over the entire porous layer. The number of macroperforations decides macroporosity value. The system under investigation is an acoustic cavity having a layer of poroelastic material rigidly attached on one side and excited by an internal point source. The overall sound pressure level (SPL) inside the cavity coupled with porous layer is calculated using mixed displacement-pressure finite element formulation based on Biot-Allard theory. A 32 node, cubic polynomial brick element is used for discretization of both the cavity and the porous layer. The overall SPL in the cavity lined with porous layer is calculated for various macroporosities ranging from 0.05 to 0.4. The results show that variation in macroporosity of the porous layer affects the overall SPL inside the cavity. This variation in macroporosity is based on the cavity mode shapes. The optimum range of macroporosities in poroelastic layer is determined from this analysis. Next, SPL is calculated considering periodic and nodal line based optimum macroporosity. The corresponding results show that locations of macroperforations based on mode shapes of the acoustic cavity yield better noise reduction compared to those based on nodal lines or periodic macroperforations in poroelastic material layer. Finally, the effectiveness of double porosity materials in terms of overall sound pressure level, compared to equivolume double layer poroelastic materials is investigated; for this the double porosity material is obtained by filling the macroperforations based on mode shapes of the acoustic cavity.

EMG Analysis of Lower Extremity Muscles under different heel types of shoes when performing Tango Backward Walk (탱고 backward walk 동작시 신발 굽 유형에 따른 하지의 근전도 분석)

  • Jeong, Mi-Ra;Seo, Kuk-Woong;Gang, Yeong-Teag;Youm, Chang-Hong
    • Korean Journal of Applied Biomechanics
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    • v.12 no.1
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    • pp.31-46
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    • 2002
  • The purpose of this research is to provide scientific training guides and the basis for preventing injuries in performing tango backward walk by comparing the effects the height and shape of a heel will have on leg muscles and determining the difference between skilled and unskilled dancers through EMG analysis according to different types of shoes Total eight female athletes were selected for this research. Four with six years of professional dancing experience and another four with one year of dance sports experience. Utilizing the EMG system, rectus femoris, biceps femoris, anterior tibialis, gastrocnemius were measured under different heights (0cm, 5cm, 7cm, 9cm) and shapes (flat, fine, wide) of a heel. Experiments were conducted calculating EMG peak value and muscle load ration under different types of shoes in order to analyze the EMG of leg muscles and Erector Spinae when performing tango backward walk. The result was as follows: 1. The EMG peak value of leg muscles showed significant difference under different heights of a heel in anterior tibialis(p<.001) and gastrocnemius(p.<01) in case of skilled dancers, and in biceps femoris(p.<01) in case of unskilled dancers. 2. The EMG peak value of leg muscles showed significant difference under different shapes of a heel in anterior tibialis(p<.001) and gastrocnemius(p<.001) in case of skilled dancers, and showed no significant difference in case of unskilled dancers. 3. The muscle load ration of leg muscles showed different degrees of muscle contribution between skilled and unskilled dancers. The muscle load ration was in the order of anterior tibialis, rectus femoris, biceps femoris, and gastrocnemius in case of skilled dancers and anterior tibialis, gastrocnemius, biceps femoris, and rectus femoris in case of unskilled dancers.

Diversity and origin of bottle gourd, Lagenaria

  • Yuasa, Hiroshi
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2002.11a
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    • pp.96-97
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    • 2002
  • Bottle gourd, Lagenaria siceraria, is one of the oldest cultivated plants. To bigin with, its fruit was used as a complete liquid bottle or container. It was a very widespread cultivated plant in prehistoric times, for example (there) is a report from Peru as early as between 13,000 B.C and 11,000 B.C. The dug-out finds in Japan proved to be about 95,000 years old according to the /sup 14/C analysis. The bottle grourd was the most important plant before the invention of pottery in many areas of Asia, New Guinea, Polynesia, America, and Africa. I would like to suggest that there should be "The Bottle Gourd Age" prior to the Pottery Age. Bottle gourds are also used for various purposes such as food, masks, pipes, musical instruments, medicine, symbols, artistic products and also as penis-sheaths of men's attire. Their purposes number more than 220 including 70 varienties of containers or bottles. I consider that its utilization should be called a culture, as it were, "The gourd culture." The shape and the size of the fruit of bottle gourd have a larger variety than those of any other plant. As for the size, it is reported that they range from those that are shorter than 3cm to those that are ovoid and longer than 60cm in diameter. With regard to the shape of its fruit, the bottle gourd can be classified into 7 groups and even more than 30 races, considering the difference of the size. The seeds are so variable without two horn-like projections, with smooth surface or longitudinalines, white or brown, with smooth corky margin. Generally, it seems that there is no correlation between seem shape and fruit shape. My study shows that the seeds of gourd. My study shows that the seeds of gourd in Asia are so simple in shape and in color except for the size. But the seeds of those in Africa are various and seem to be beyond the confines. Explaining the great diversity of the seeds of those in Africa therefore, they appear to have no correlation among the types of fruit of the bottle gourd with African origin. It might be supposed that another 4 wild Lagenaria spp. distribute only in Africa. The intraspecies hybrid is confirmed between the bottle gourd, Lagenaria siceraria, and wild L. spehaerica. And Fl hybrid is sterile: it has no fertility. However, even though the shapes of the fruit and the seeds are different, they can cross with each other. Moreover, their hybrids grow up to be extremely vigorous and have normal fertility. Fruit shapes of Fl plants are similar to those of their parents, if they have the same character. Whereas, the fruit shape often became different from each other when the cross occurs between those with different fruit shapes. It is shown that dumbbell shapes, HYOTAN in Japanese, is recessive while its bitterness is dominant. Thus the character of F2 hybrids Is segregative. I'll give further particulars of the heredity of the groud in my lecture.

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