• Title/Summary/Keyword: Asymmetric angle

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A convergence study of the effects of asymmetric standing posture on knee joint position and lower extremity muscle activity in subjects with hyper-extended knee (무릎 과다 폄을 가진 대상자에게 비대칭 선 자세가 무릎 관절 위치와 근활성도에 미치는 영향에 대한 융합적 연구)

  • Jung, Sung-hoon;Ha, Sung-min
    • Journal of the Korea Convergence Society
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    • v.10 no.9
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    • pp.63-68
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    • 2019
  • The purpose of this study was to investigate the effect of hyper-extended knee and asymmetric standing posture on knee joint position and lower extremity muscle activity. Thirty-three voluntary participants participated and included sixty legs in the study. The sixty legs were divided into two groups: hyper-extended knee and normal group. The muscle activity and knee extension angle were measured. In the asymmetric standing posture, the knee joint extension angle and the muscle activity of the gastrocnemius were statistically significant between the normal group and the hyper-extended knee group. Based on the results, we confirmed that the asymmetric standing posture increases the hyper-extended knee. Therefore, it will contribute to the establishment of therapeutic guide for the subjects with hyper-extended knee to maintain the symmetrical standing posture, and future studies need to be conducted including the effects of the hip joint and ankle joints.

A Decision Method for the Optimal Insertion Resistance of a Superconducting Fault Current Limiter with Reduction of an Asymmetric Fault Current (비대칭 고장전류 저감 기능을 갖는 초전도 한류기의 최적 저항 결정 방안)

  • Kim, Chang-Hwan;Kim, Kyu-Ho;Rhee, Sang-Bong
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.64 no.1
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    • pp.57-63
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    • 2015
  • Fault currents characteristics contain decaying DC offset. First cycle peak value of fault currents is higher than steady-state fault current value. These characteristics can affect the operation of protective device. To reduce the asymmetric fault current, the method using a series connection of two hybrid-type Superconducting Fault Current Limiter(SFCL) components, an auxiliary SFCL and a main SFCL, has been proposed. The auxiliary SFCL limits the first half cycle fault current, while main SFCL limits the steady state fault currents. This paper proposed a decision method of the optimal insertion resistance of auxiliary and main SFCL components. To verify the effectiveness of proposed scheme, the various simulations are performed by using Electromagnetic Transient Program(EMTP).

Mechanical properties and formability of asymmetrically rolled aluminum alloy sheet (무윤활 압연한 알루미늄 판재의 기계적 특성과 성형성)

  • Akramov, S.;Kim, In-Soo
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2009.05a
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    • pp.429-431
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    • 2009
  • Drawability and other mechanical properties of sheet metals are strongly dependent on their crystallographic orientations. In this paper the formability of the AA 5052 Al alloy sheets was investigated after asymmetric rolling and subsequent heat treatment. In most cases, after asymmetric rolling specimens showed a fine grain size and subsequent heat treated specimens showed that the ND // <111> texture component were observed. The anisotropy of formability is often described by the plastic strain ratios (r-value) as a function of the angle to the rolling direction in sheet metal. For a good formability, a high r-value is required in sheet metals. In the asymmetry rolled and subsequent heat treated Al alloy sheet, the variation of the plastic strain ratios have been investigated in this study, The plastic strain ratios of the asymmetry rolled and subsequent heat treated AA 5052 Al alloy sheets were higher than those of the original Al sheets. These could be related to the formation of ND // <111> texture components through asymmetric rolling in Al sheet.

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Effects of Hot Asymmetric Rolling on Microstructure and Formability of Aluminum Alloys (고온 비대칭압연이 알루미늄 합금의 미세조직과 성형성에 미치는 영향)

  • Jeong, Museob;Lee, Jongbeom;Han, Jun Hyun
    • Korean Journal of Materials Research
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    • v.29 no.10
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    • pp.647-655
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    • 2019
  • In order to analyze the effect of hot asymmetric rolling on the microstructure and texture of aluminum alloy and to investigate the effect of the texture on the formability and plastic anisotropy of aluminum alloy, aluminum 6061 alloy is asymmetrically rolled at room temperature, $200^{\circ}C$, $350^{\circ}C$, and $500^{\circ}C$, and the results are compared with symmetrically rolled results. In the case of asymmetric rolling, the equivalent strain (${\varepsilon}_{eq}$) is greatest in the upper roll part where the rotational speed of the roll is high and increases with increasing rolling temperature. The increase rate of the mean misorientation angle with increasing temperature is larger than that during symmetrical rolling, and dynamic recrystallization occurs the most when asymmetrical rolling is performed at $500^{\circ}C$. In the case of hot symmetric rolling, the {001}<110> rotated cube orientation mainly develops, but in the case of hot asymmetric rolling, the {111}<110> orientation develops along with the {001}<100> cube orientation. The hot asymmetric rolling improves the formability (${\bar{r}}$) of the aluminum 6061 alloy to 0.9 and reduces the plastic anisotropy (${\Delta}r$) to near zero due to the {111}<110> shear orientation that develops by asymmetric rolling.

The Effect of Korean Medical Treatments for Facial asymmetry Patients : Five Cases Report (한의학적 치료로 호전된 안면비대칭 5례)

  • Shin, Jeongmin;Ah, Jin-hyang;Lee, Jin-hyuk
    • The Journal of Korean Medicine
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    • v.40 no.3
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    • pp.198-223
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    • 2019
  • Objectives: The purpose of this study was to investigate the effect of Korean medicine treatment on facial asymmetric treatment in 5 cases of facial asymmetry correction by non - surgical treatment such as acupucture, chuna treatment, FCST (Functional cerebrospinal technique) and cranial osteopathy. Methods: We analyzed the initial charts of 5 patients who had undergone facial asymmetry in a Korean medicine clinic and measured the position and distance using the photograph, lateral cephalograms, and whole body radiograms. The results were as follows. Results: To quantify both soft and hard tissues to confirm the results of Korean medicine treatment of facial asymmetry, soft tissues quantitatively measure the displacement of the face, the slope of the left and right eyes, and the slope of the lip in order to grasp the positional displacement of the mandible. As a result, on the average, the correction effect as measured by the angle difference between A and C is $1.8{\pm}0.57$, the correction effect as measured by the angle difference between B and C is $1.4{\pm}0.89$, and the angle difference between D and the horizontal plane is $1.9{\pm}0.89$, and the angle difference between E and the horizontal plane is $1.9{\pm}0.89$. The result of reduced angle difference between A and C means that the head position shifted from the center of the body to the unilateral side was shifted to the center. The decrease in the angle difference between B and C means the restoration of the maxillary distortion relative to the mandible. In hard tissues, numerical values were measured based on the skull standard. The average distortion of the skull was $1.9{\pm}0.67$, and the distortion of the lower eye was $1.4{\pm}0.41$. Conclusion: General studies on facial asymmetric treatment are limited to treatments such as surgery and orthodontics. However, this study confirmed the possibility that facial asymmetry could be corrected by Korean medical treatment consisting of reversible non-surgical treatment rather than irreversible treatment such as surgery or orthodontic treatment. In particular, Korean medicine treatment is effective for muscular asymmetry, soft asymmetry, functional asymmetry, etc. The facial asymmetric treatment of Korean medicine is not limited to the face-centered correction, but the asymmetry of the whole body may be corrected as well.

Switching Angle Selection for Maximum Torque in Toroidal SRM (Toroidal SRM의 최대토크 스위칭각 선정)

  • 차현록;김현덕;김광헌;임영철;최유영;최강식;전흥기
    • Proceedings of the KIPE Conference
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    • 1999.07a
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    • pp.135-138
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    • 1999
  • This paper analysis magnetic circuit of toroida SRM and simulate optimal switching angle. In this troidal SRM, two of three phase are energized at an arbitrary instance while it is with only one phase in case of typical SRM. It has many advantages in the size of machine and power efficiency. Not only typically Known topologies witched reluctance motors such as asymmetric converter but full bridge converter are safe to employ

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Illuminance Distribution Variation with the Angle of Reflectors (반사갓의 각도에 따른 조도분포 변화)

  • Ma, Tae-Young
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.24 no.9
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    • pp.16-19
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    • 2010
  • In this paper, we fabricated angle-changable two-stage reflectors and measured the illuminance as a function of the angle of reflection plates. The illuminance of center areas could be controlled by changing the angle of upper reflection plates and the illuminated area expanded with reducing the angle of lower reflection plates. The bright spots could be moved using asymmetric structures of reflection plates. It was found that the distribution of illuminance matches well with the Gaussian distribution function. From the results of curve fitting, it was found that without reflectors, a half of the lights emitted from fluorescent lamp do not reach the working place. A simple model was suggested to explain the illuminance variation with the structure of reflector.

Pretilt Angle Generation and EO Performance in MLC with Polarized UV Light Irradiation Polyimide surface (폴리이미드막 표면에 직선 편광된 UV광 조사에 의한 프리틸트각 발생과 전기광학특성)

  • 서대식;이정호;이창훈
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.11 no.10
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    • pp.878-884
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    • 1998
  • We have investigated that the monodomain alignment of nematic liquid crystal (NLC) is obtained with polarized ultraviolet(PUV) light irradiation on polyimide (PI) surface. The LC alignment capability increases with increasing the UV light irradiation time. The polarized UV light irradiation on oblique angle of 60。 irradiated on PI surface rotated by 90。 at 10 min. after being normally irradiated on PI surface at 30 min., the generated pretilt angle of NLC is about 2.5。. The pretilt angle of NLC is attributed to the interaction between the LC molecules and the asymmetric triangular structure of polymer surface due to photo-depolymerization of polymer with the oblique UV light on PI surface. The voltage -transmittance and response time characteristics of photo-aligned twisted nematic (TN)-LCD with UV light irradiation time 60 min. were almost same in comparison with the rubbing-treated TN-LCD.

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Effects of Angles of Attack and Throttling Conditions on Supersonic Inlet Buzz

  • NamKoung, Hyuck-Joon;Hong, Woo-Ram;Kim, Jung-Min;Yi, Jun-Sok;Kim, Chong-Am
    • International Journal of Aeronautical and Space Sciences
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    • v.13 no.3
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    • pp.296-306
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    • 2012
  • A series of numerical simulations are carried out to analyze a supersonic inlet buzz, which is an unsteady pressure oscillation phenomenon around a supersonic inlet. A simple but efficient geometry, experimentally adopted by Nagashima, is chosen for the analysis of unsteady flow physics. Among the two sets of simulations considered in this study, the effects of various throttling conditions are firstly examined. It is seen that the major physical characteristic of the inlet buzz can be obtained by inviscid computations only and the computed flow patterns inside and around the inlet are qualitatively consistent with the experimental observations. The dominant frequency of the inlet buzz increases as throttle area decreases, and the computed frequency is approximately 60Hz or 15% lower than the experimental data, but interestingly, this gap is constant for all the test cases and shock structures are similar. Secondly, inviscid calculations are performed to examine the effect regarding angle of attack. It is found that patterns of pressure oscillation histories and distortion due to asymmetric (or three-dimensional) shock structures are substantially affected by angle of attack. The dominant frequency of the inlet buzz, however, does not change noticeably even in regards to a wide range of angle of attacks.

The Study of Steering Effect in Multilayer Growth (두꺼운 박막 성장시 Steering 효과 연구)

  • Seo J.;Kim J.S.
    • Journal of the Korean Vacuum Society
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    • v.15 no.4
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    • pp.410-420
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    • 2006
  • The dynamic effects, such as the steering and the screening effects during deposition on an epitaxial growth is studied by kinetic Monte Carlo simulation. In the simulation, we incorporates molecular dynamic simulation to rigorously take the interaction of the deposited atom with the substrate atoms into account, We find three characteristic features of the surface morphology developed by grazing angle deposition: (1) enhanced surface roughness, (2) asymmetric mound, and (3) asymmetric slopes of mound sides, Regarding their dependence on both deposition angle and substrate temperature, a reasonable agreement of the simulated results with the previous experimental ones is found. The characteristic growth features by grazing angle deposition are mainly caused by the inhomogeneous deposition flux due to the steering and screening effects, where the steering effects play the major role rather than the screening effects. Newly observed in the present simulation is that the side of mound in each direction is composed of various facets instead of all being in one selected mound angle even if the slope selection is attained, and that the slope selection does not necessarily mean the facet selection.