• Title/Summary/Keyword: Phase Asymmetry

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Functional evaluation of orthopedic and orthodontic treatment in a patient with unilateral posterior crossbite and facial asymmetry

  • Kwak, Yoon-Young;Jang, Insan;Choi, Dong-Soon;Cha, Bong-Kuen
    • The korean journal of orthodontics
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    • v.44 no.3
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    • pp.143-153
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    • 2014
  • An 8-years old boy with facial asymmetry and unilateral posterior crossbite on the left side received orthopedic and orthodontic treatment. During the first phase of treatment, the narrow maxillary arch was expanded using an acrylic plate. Then, the acrylic plate was used as a bite block with occlusal indentations from the construction bite that was obtained with the incisors in a coincident dental midline. After the position of the mandible was stabilized, the second phase of orthodontic treatment was initiated using fixed appliances for detailing of the occlusion. Skeletal symmetry, ideal occlusion, and coincident dental midlines were thus achieved. Functionally, occlusal force balance and masticatory muscle activity were improved, and the chewing patterns were normalized.

Solar North-South Asymmetry and Hilbert Transform Analysis

  • Heon-Young Chang
    • Journal of The Korean Astronomical Society
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    • v.56 no.1
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    • pp.125-135
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    • 2023
  • Here, we investigated the observed sunspot areas with respect to latitudes using the Hilbert transform technique. Conventional study of the cyclic patterns of sunspots is based on the Lomb-Scargle periodogram, which only obtains the amplitude information. In comparison, our approach characterizes the amplitude as well as the phase of solar activity. We demonstrated the solar North-South asymmetry in the instantaneous amplitude by analyzing daily sunspot data set spanning from the solar cycles 11 to 24. Our findings confirm that the northern hemisphere is dominant in the solar cycles 14, 15, 16, 18, and 20. Unlike the amplitude, the North-South asymmetry in the period of solar activity could not be established. We have also found that the standard deviation as a measure of fluctuation in the phase derivative is minimum in the latitude band 10° < l < 20°, and the fluctuations obtained for latitudes above 30° are considerable.

The Nonstationary Vibration of Asymmetry Shaft Carrying two Discs Passing through Critical Speeds

  • Bo Suk Yang
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.16 no.2
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    • pp.77-84
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    • 1980
  • The nonstationary vibration of a rotor carrying two discs with a limited driving torque is studied theoretically by using the method of the perturbation theory. The influence of the asymmetry, torque, damping and phase difference in passing through a critical speed is studied in detail, considering the interaction between the driving source and the vibration system.

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Microstructure and Yield Asymmetry Behavior of Indirect-extruded Mg-Sn-Al-Zn Alloys (Mg-Sn-Al-Zn 마그네슘 합금 간접압출재의 미세조직 및 소성이방성)

  • Park, S.H.;Kim, Y.M.;Kim, H.S.;Yim, C.D.;You, B.S.
    • Transactions of Materials Processing
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    • v.21 no.5
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    • pp.324-329
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    • 2012
  • Mg-(9-x)Sn-xAl-1Zn (x=1, 2, 3 and 4 wt.%) alloys were subjected to indirect extrusion, and the microstructure and mechanical properties of the as-extruded Mg-Sn-Al-Zn (TAZ) alloys were investigated. The TAZ 811 alloy exhibited a finer grain structure than the TAZ 541 alloy due to a larger number of Mg2Sn particles, which pinned the grain boundaries and prevented growth of recrystallized grains. The TAZ alloys showed an unusual yield asymmetry behavior. The tension-compression yield asymmetry increased with decreasing average grain size. The TAZ 811 alloy with a small grain size exhibited a larger yield asymmetry than that of the TAZ 541 alloy having a relatively large grain size, which is mainly attributed to the low Al content and large number of second phase particles in the TAZ 811 alloy.

Theoretical Analysis of Chromatographic Peak Asymmetry and Sharpness by the Moment Method Using Two Peptides

  • Choi Du Young;Row Kyung Ho
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.9 no.6
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    • pp.495-499
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    • 2004
  • The analyses of peak shapes in chromatography are useful in operating chroma­tographic system. The asymmetry and sharpness of a chromatographic peak are estimated by the reversed-phase adsorption of two standard peptides (angiotensin II bradykinin) on $C_{18}$ In this work, the average particle diameters of $C_{18}$ were 5 and 15 $\mu$m, while the pore sizes were 100 and 300 A. The composition of the mobile phase was $50/50\;vol.\;{\%}$ of a binary mixture of acetonitrile and water with $0.1\%$ TFA, and the particles were packed in a stainless column ($4.6{\times}150$ mm). The third and the fourth central movement were calculated from the chromatographic elution curves by moment analysis. The peak asymmetry was determined by two theoretical calculations: the asymmetry factor by elution peak analysis and skewness with moment analysis. The sharpness was estimated by the fourth central moment. In this work, the most acceptable skewness was calculated when the pore size was 300 A. The large excess was observed on small pore size.

A Study On The Performances Of A Single-Phase Motor With Non-Quadrature Stator Windings Using Domestic Magnetic Materials. (국산자기재료를 이용한 비대칭자속분포 단상유도기구)

  • Min Ho Park
    • 전기의세계
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    • v.21 no.3
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    • pp.41-47
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    • 1972
  • The requirements of a successful design for single phase induction motors with a high efficiency have, in recent years, led to the use of non-quadrature stator windings motors in which a high starting torque is a prime requisite. The capacitor motor is one of above machines in which various possible forms of asymmetry can be occur. These forms of asymmetry in the stator phase windings, encountered in machine designs, are 1) an asymmetrical disposition in space of their magnetic axes, 2) a difference in their effective number of turns, 3) a difference in the distribution of their coil groups per pole and 4) amounts of capacitance of an auxiary winding. In order to apply the effective performance prediction of these form to motors, mading of lower quality-domestic magnetic materials, the analysis and the experimental investigations of its sample motors are described in this paper. The utility of such a motor is demonstrated and it is shown that the effects- a good efficiency, good power factor and high starting torque-of the motor mechanism with non-quadrature stator phase windings can development disadvantages by using the lower quality-domestis magnetic materials.

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$^{87}Rb$ NMR Quadrupole Coupling Constants and Asymmetry Parameters in $RbMnCl_3$

  • Woo, Ae-Ja;Park, Young-Sun
    • Journal of the Korean Magnetic Resonance Society
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    • v.3 no.2
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    • pp.84-89
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    • 1999
  • The 87Rb quadrupole coupling constants (e2qQ/h) and the asymmetry parameters (η) in RbMnCl3 were determined from a nonlinear least-squares fit to the 87Rb NMR powder spectra. The spectra were acquired in the temperature range from 260K to 330K. An important feature in this work is the determination of the quadrupole coupling constants and the asymmetry parameters for two physically nonequivalent Rb sites, Rb(I) and Rb(II), as a function of temperature. In addition, a structural phase transition at room temperature was conformed with the changes in the quadrupole coupling constant and the asymmetry parameter of Rb(II) site.

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THE LONG-TERM HEMISPHERIC VARIATION OF POLAR FACULAE

  • Deng, Lin-Hua;Qu, Zhong-Quan;Liu, Ting;Huang, Wen-Juan
    • Journal of The Korean Astronomical Society
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    • v.44 no.6
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    • pp.209-215
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    • 2011
  • In this paper, the long-term hemispheric variation of the polar faculae is investigated. It is found that, (1) both the N-S asymmetry and N-S asynchrony of the polar faculae exhibit a long-term persistence, which suggests that they should not be regarded as a stochastic phenomenon; (2) both the N-S asynchrony and N-S asymmetry of the polar faculae are functions of the latitude, implying that the N-S asynchrony of the polar faculae is related to the N-S asymmetry of the polar faculae; (3) from a long-term view, the dominant hemisphere of the polar faculae seems to have close connection with the phase-leading hemisphere of the polar faculae.

Gait Asymmetry in Children with Down Syndrome (다운증후군 아동들의 보행 비대칭성 연구)

  • Lim, Bee-Oh;Han, Dong-Ki;Seo, Jung-Suk;Eun, Seon-Deok;Kwon, Young-Hoo
    • Korean Journal of Applied Biomechanics
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    • v.16 no.2
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    • pp.145-151
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    • 2006
  • A large interindividual variability and some abnormally kinematic patterns at the lower extremity were the main features of the gait in children with Down syndrome. The purposes of this study were to investigate the gait asymmetry and biomechanical difference between dominant leg and non dominant leg in children with Down syndrome. Seven boys with Down Syndrome(age: $120{\pm}0.9yrs$, weight $34.4{\pm}8.4kg$, leg length: $68.7{\pm}5.0cm$) participated in this study. A 10.0 m ${\times}$ 1.3 m walkway with a firm dark surface was built and used for data collection. Three-dimensional motion analyses were performed to obtain the joint angles and range of motions. The vertical ground reaction forces(%BW) and impulses($%BW{\cdot}s$) were measured by two force plates embedded in the walkway. Asymmetry indices between the legs were computed for all variables. After decision the dominant leg and the non dominant leg with max hip abduction angle, paired samples t-test was employed for selected kinematic and ground reaction force variables to analyze the differences between the dominant leg and the non dominant leg. The max hip abduction angle during the swing phase showed most asymmetry, while the knee flexion angle at initial contact showed most symmetry in walking and running. The dominant leg showed more excessive abduction of hip in the swing phase and more flat-footed contact than the non dominant leg. Vertical peak force in running showed more larger than those of in walking, however, vertical impulse showed more small than walking due to decrease of support time. In conclusion, the foot of dominant leg contact more carefully than those of non dominant leg. And also, there are no significant difference between the dominant leg and the non dominant leg in kinematic variables and ground reaction force due to large interindividual variability.

Three Phase GTO PWM Inverter Using the Energy Recovery Snubber Circuit (에너지 회생 방식 스너버 회로를 각는 3상 GTO PWM 인버터)

  • 신병철;강경호;차재현;차득근;김명현
    • Proceedings of the KIPE Conference
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    • 1998.07a
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    • pp.255-259
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    • 1998
  • This paper is proposed three phase GTO PWM Inverter with energy recovery snubber circuit. The proposed energy recovery snubber circuit effective in reduction of the power loss in the Inverter system than asymmetry GTO snubber circuit.

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