• Title/Summary/Keyword: angle

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Analysis of Successful Landing by the Type of the Salto Backward (뒤 공중 돌기 유형에 따른 착지동작의 성공요인 분석)

  • Han, Yoon-soo
    • Korean Journal of Applied Biomechanics
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    • v.14 no.1
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    • pp.1-12
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    • 2004
  • The purpose of this study is to provide training materials for practical use by investigating the kinematical variables of the successful landing by the type of the salto backward such as Tuck, Pike. For this study, the subjects are 4 male national gymnasts using 3-dimensional cinematographic method. Based on the results of this study, the conclusions are drawn as follows. 1. In flight phase, Tuck and Pike show fast extension after completing minimum angle of hip joint passing through the peak. It is very important factor to control body with gaining time before landing while decreasing the velocity of flight rotaion. 2. In Landing phase, the angles of each joint for successful landing are shown as $92deg{\sim}100deg$ for knee angle, $52deg{\sim}57deg$ for hip angle, and $56deg{\sim}70deg$ for shoulder angle. 3. Tuck and Pike dramatically decrease the height of COG, and horizontal/vertical velocity of COG from TD to LD. Also, it is shown that the knee angle, the hip angle and the shoulder angle decrease drastically. On the other hand, the angular velocity of trunk rotation shows negative direction and due to this, the angle of trunk rotation is shown as re-flexion.

Changes in Curve-Angle of Blade during Salting of Chinese Cabbage (배추의 소금절임중 엽신의 휘임도 변화)

  • Kim, Mi-Gyeong;Kim, Il-Du;Kim, Sun-Dong
    • Food Science and Preservation
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    • v.4 no.2
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    • pp.163-171
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    • 1997
  • This study was undertaken to investigate changes m curve angle of Chinese cabbage blade during salting at various concentration(10, 15, 20, 25%) of salt to evaluated salting degree by curve angle during salting at 20$^{\circ}C$. Salt concentration of brine, the amount of water elution, salt penetration of the tissue(salt concentration of Chinese cabbage), weight loss and texture were investigated. Correlation relation between the above factors and curve angle were determined. The curve angles by method of holding the edge of the Chinese cabbage blade was measured. The curve angles of the mesophyll were proportional to salting time and salt concentration, but slope of line equation showed higher than that of mid-rib. The ideal method of salting evaluation by curve angle was MCA-MRC (the measuring curve angle of mid-rib C) at each concentration of salt. The results of curve angle when reached 3% salt of Chinese cabbage tissue calculated by MCA-MRC at 10, 15, 20 and 25% salting were 57$^{\circ}$, 43$^{\circ}$, 36$^{\circ}$, and 33$^{\circ}$, respectively. And salting times calculated by the same conditions were 19, 12.5, 9.1 and 4.4hours, respectively.

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The study of defrosting performance on automobile Windshield through different injection angle (Different injection angle에 따른 자동차 전면 유리 제상성능 연구)

  • Kang, Hyu-Goo;Lee, Kum-Bae;Kader, Md. Faisal;Oh, Gyu-Nam
    • Proceedings of the KSME Conference
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    • 2008.11b
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    • pp.2454-2459
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    • 2008
  • The objective of this paper is to find out the most effective injection angle for the purpose of deicing through SC/Tetra, a commonly used CFD software. Nowadays, vehicles are developed giving priority to an improved interior which emphasizes a pleasant environment and thermal comfort without decreasing the basic performance. Clear visibility is one of the most important phenomenon. The primary factors which affect the efficiency of deicing are 3D geometry of Defrost Nozzle, the inlet velocity and temperature of the flow and the injection angle. However in this paper, all these parameters are optimized by changing the injection angle. A wide range of injection angle from 5 degree to 50 degree have been considered for analysis. A very good defrosting performance has been achieved with 45 degree injection angle which can satisfy the condition of NHTSA.

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An Experimental Study on Selection Pitch Angle on backward flow of an Axial Fan with Adjustable Pitch Angle Blades (피치각 조정형 송풍-역풍 겸용 축류팬에서 배연용 피치각 선정을 위한 실험적 연구)

  • Chang, Taek-Soon;Hur, Jin-Huek;Moon, Seung-Jae;Lee, Jae-Heon;You, Ho-Sun;Im, Yun-Chul
    • Proceedings of the SAREK Conference
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    • 2008.11a
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    • pp.145-150
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    • 2008
  • In this study, the experimental study has carried out to select pitch angle on the backward flow in an axial fan that has adjustable pitch blades. With the change of pitch angle of axial fan with adjustable blade, air flow rate, pressure and air flow direction can be changed. Because of this merit, adjustable axial fan can be used in the backward flow. For the selection of the backward flow pitch angle, fan performance test method is selected by KS B 6311. Dynamic pressure, static pressure, electric current and voltage are measured in each pitch angles of axial fan that are $36^{\circ}C$, $-16^{\circ}C$, $-21^{\circ}C$, $-26^{\circ}C$, $-31^{\circ}C$ and $-36^{\circ}C$. In the result of test, fan performance curves at several pitch angle has been investigated. Finally, pitch angle of $-26^{\circ}C$ has been selected to get largest flow rate at backward flow situation.

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The Effects of Screen Smart Devices on the Neck Flexion Angle

  • Lee, Jun Cheol;Kim, Kyung
    • Journal of International Academy of Physical Therapy Research
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    • v.7 no.2
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    • pp.1051-1055
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    • 2016
  • The purpose of this study was to investigate the effect of the screen size of smart devices on the bending angle of the cervical spine. The subjects of this study were 30 healthy adults(15 men and 15 women) who used smartphones and tablet PC(personal computer). The changes in the bending angle of the upper and lower cervical spine were measured in the subjects after they had used a smartphone and a tablet PC for 300 seconds each. To make sure that all subjects began in the same starting position, an angle-measuring instrument was used to set the angles of the ankle, knee, hip, and arm joints to 90 degree. The subjects were asked to keep the trunk straight. They were asked to hold a smartphone in their hand and to bend their neck so that they could look down at the screen. Once they began using the smartphone in this manner, they were free to change their posture. We used a paired t-test to compare the bending angle of the cervical spine on subjects who used smartphones and tablet PC in the long-term and short-term there production error of cervical and the significance level was cervical. The results showed that, when using a smartphone and a tablet PC for 300 seconds, there was no significant difference in the bending angle of the upper cervical spine(p>.05), although there was a significant difference in the bending angle of the lower cervical spine(p<.05).

A STUDY ON THE ATTRITION OF MAXILLARY CENTRAL INCISORS IN KOREAN (한국인 상악중절치의 교모에 관한 연구)

  • Park, Chong-Wha
    • The Journal of Korean Academy of Prosthodontics
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    • v.16 no.1
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    • pp.32-37
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    • 1978
  • The purpose of this study was to apply the position, the form and the angle of the attrition in the natural maxillary central incisors shown on the labial surface to the artificial teeth in the field of prosthetic dentistry. So we should exactly alter the molds of artificial teeth in individual cases in order to make artificial teeth more natural. 226 extracted teeth of the maxillary central incisors were chosen as materials. I have exactly examined the teeth with a magnifying glass and a circular graduator under concentrated light. The observation brought me the following results: 1) The attrition was most prevailing at the range from the mesial angle to the middle part of cutting edge in the left maxillary central incisor, and distal angle of cutting edge in the right maxillary central incisor. 2) On the attrite form of both angles, the angulated form was more than 4 times as frequent as rounded form in the mesial angle, and almost equal in the distal angle. 3) On the attrite form of cutting edge, mesial attrite form including mesial angle was most frequent in the left maxillary central incisor, and distal attrite form including distal angle in the right maxillary central incisor. 4) The angle made by the labial surface and the attrite surface was about $39^{\circ}$, and more than 70% of the total examined teeth were included at the range from $31^{\circ}\;to\;50^{\circ}$. 5) None attrite form at the cutting edge was about 12% and completely attrite form at the cutting edge was about 27% of examined teeth.

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Precise calibration of the angle of ncidence in spectroscopic ellipsometer (분광 타원해석기 입사각의 정밀 보정)

  • 김현종;김상열;이윤우;조현모;조용재;이인원
    • Korean Journal of Optics and Photonics
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    • v.10 no.3
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    • pp.208-213
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    • 1999
  • We proposed a new technique to precisely calibrate the angle of incidence in spectroscopic ellipsometer. The proposed technique can be useful to the thickness measurement of semiconductor thin films and optical thin films. The usefulness has been confirmed experimentally. We cut a block of optical glass into two pieces and made a prism as well as a slab using each piece. The apex angle and the angle of the minimum deviation of prism were measured. From these angles, the refractive index of glass material was calculated. From the analysis of the spectro-ellipsometric data collected near Brewster's angle, we could not only determine the error in the angle of incidence in the spectroscopic ellipsometer, but also calibrated the angle of incidence to the accuracy of 0.01 degree.

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Scoliosis Progression according to the Growth of Middle School Students (성장에 따른 중학생 척추측만증 이행양상)

  • Kim, Juk-Hyang;Kim, Eun-Ju
    • Research in Community and Public Health Nursing
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    • v.14 no.3
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    • pp.479-487
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    • 2003
  • Purpose: This study was conducted to investigate the progression of Cobb's angle of middle school students according to the Risser grade changes during a one-year follow up period, and to identify the prevalence rate and related factors regarding scoliosis. Method: A total of 2,124 middle school students were preliminarily screened by the Adam's forward bending test. Among them, 21 adolescents diagnosed with scoliosis (above 5Cobb's angle) by X-Raying were the subjects and followed up for checking Cobb's angle and the Risser grade for one year. Results: The overall prevalence of scoliosis in middle school students was 2.13% and the prevalence in girls was higher than in boys. The Cobb's angle was significantly high in seniors and girls. The cases in low angle and low Risser grade demonstrated significant changes in progressive Cobb's angle compared to the cases in high angle and high Risser grade after one-year. But gender and pattern of curvature were not significantly different from the changes scoliosis angle after one-year. Conclusion: Based on these study results, juniors in low Risser grade were inclined to aggravate scoliosis despite the low degree of curvature at the first measurement.

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Electromagnetic interference shielding characteristics for orientation angle and number of plies of carbon fiber reinforced plastic

  • Kim, Hong Gun;Shin, Hee Jae;Kim, Gwang-Cheol;Park, Hyung Joon;Moon, Ho Joon;Kwac, Lee Ku
    • Carbon letters
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    • v.15 no.4
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    • pp.268-276
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    • 2014
  • Recently, methods that usea carbon-based filler, a conductive nanomaterial, have been investigated to develop composite fillers containing dielectric materials. In this study, we added geometric changes to a carbon fiber, a typical carbon-based filler material, by differentiating the orientation angle and the number of plies of the fiber. We also studied the electrical and electromagnetic shield characteristics. Based on the orientation angle of $0^{\circ}$, the orientation angle of the carbon fiber was changed between 0, 15, 30, 45, and $90^{\circ}$, and 2, 4, and 6 plies were stacked for each orientation angle. The maximum effect was found when the orientation angle was $90^{\circ}$, which was perpendicular to the electromagnetic wave flow, as compared to $0^{\circ}$, in which case the electrical resistance was small. Therefore, it is verified that the orientation angle has more of an effect on the electromagnetic interference shield performance than the number of plies.

Multi-granular Angle Description for Plant Leaf Classification and Retrieval Based on Quotient Space

  • Xu, Guoqing;Wu, Ran;Wang, Qi
    • Journal of Information Processing Systems
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    • v.16 no.3
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    • pp.663-676
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    • 2020
  • Plant leaf classification is a significant application of image processing techniques in modern agriculture. In this paper, a multi-granular angle description method is proposed for plant leaf classification and retrieval. The proposed method can describe leaf information from coarse to fine using multi-granular angle features. In the proposed method, each leaf contour is partitioned first with equal arc length under different granularities. And then three kinds of angle features are derived under each granular partition of leaf contour: angle value, angle histogram, and angular ternary pattern. These multi-granular angle features can capture both local and globe information of the leaf contour, and make a comprehensive description. In leaf matching stage, the simple city block metric is used to compute the dissimilarity of each pair of leaf under different granularities. And the matching scores at different granularities are fused based on quotient space theory to obtain the final leaf similarity measurement. Plant leaf classification and retrieval experiments are conducted on two challenging leaf image databases: Swedish leaf database and Flavia leaf database. The experimental results and the comparison with state-of-the-art methods indicate that proposed method has promising classification and retrieval performance.