• Title/Summary/Keyword: spin group

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Assessment of the Location of the Peroneus Longus Tendon in the Cuboid Groove Using 3D Isotropic Fast Spin-Echo MRI

  • Lee, Ji Yoon;Choo, Hye Jung;Lee, Sun Joo;Jung, Joon-Yong;Kim, Dong Wook;Baek, Jin Wook;Heo, Young Jin;Gwak, Heui-Chul
    • Investigative Magnetic Resonance Imaging
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    • v.24 no.1
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    • pp.21-29
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    • 2020
  • Purpose: To investigate normal location of the peroneus longus tendon (PL) in the cuboid groove by evaluating it between ankles with no significant abnormality (asymptomatic group) and those with retromalleolar PL dislocation (dislocation group) using three-dimensional isotropic fast spin-echo (3D-FSE) magnetic resonance imaging (MRI) of the ankle. Materials and Methods: Thirty-six and 32 3D-FSE ankle MRI were assigned to the asymptomatic group and the dislocation group, respectively. Using multiplanar reformatted 3D-FSE, qualitative PL location (i.e., outside, overlying, and inside in relation to the cuboid groove), quantitative PL location (i.e., distance between the proximal margins of PL and cuboid groove), and cuboid groove size were measured in lateral, middle, and medial levels of the cuboid groove. Results: In the asymptomatic group, 64%, 42%, and 11%, respectively, had the outside or overlying-located PL in lateral, middle, and medial levels of the cuboid groove and the quantitative location gradually decreased from lateral to medial level. Qualitative and quantitative PL locations were not significantly different between the asymptomatic group and dislocation group. Cuboid groove size showed significant negative correlation with quantitative PL location in both groups. Conclusion: Outside- or overlying-located PL in lateral and middle levels of the cuboid groove would be a normal finding, regardless of PL status at the retromalleolar level.

QUANTUM MARKOVIAN SEMIGROUPS ON QUANTUM SPIN SYSTEMS: GLAUBER DYNAMICS

  • Choi, Veni;Ko, Chul-Ki;Park, Yong-Moon
    • Journal of the Korean Mathematical Society
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    • v.45 no.4
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    • pp.1075-1087
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    • 2008
  • We study a class of KMS-symmetric quantum Markovian semigroups on a quantum spin system ($\mathcal{A},{\tau},{\omega}$), where $\mathcal{A}$ is a quasi-local algebra, $\tau$ is a strongly continuous one parameter group of *-automorphisms of $\mathcal{A}$ and $\omega$ is a Gibbs state on $\mathcal{A}$. The semigroups can be considered as the extension of semi groups on the nontrivial abelian subalgebra. Let $\mathcal{H}$ be a Hilbert space corresponding to the GNS representation con structed from $\omega$. Using the general construction method of Dirichlet form developed in [8], we construct the symmetric Markovian semigroup $\{T_t\}{_t_\geq_0}$ on $\mathcal{H}$. The semigroup $\{T_t\}{_t_\geq_0}$ acts separately on two subspaces $\mathcal{H}_d$ and $\mathcal{H}_{od}$ of $\mathcal{H}$, where $\mathcal{H}_d$ is the diagonal subspace and $\mathcal{H}_{od}$ is the off-diagonal subspace, $\mathcal{H}=\mathcal{H}_d\;{\bigoplus}\;\mathcal{H}_{od}$. The restriction of the semigroup $\{T_t\}{_t_\geq_0}$ on $\mathcal{H}_d$ is Glauber dynamics, and for any ${\eta}{\in}\mathcal{H}_{od}$, $T_t{\eta}$, decays to zero exponentially fast as t approaches to the infinity.

Investigation of Spin Reorientation in Ga Substituted Y-type Hexaferrite based on Mössbauer Spectroscopy

  • Lim, Jung Tae;Kim, Jeonghun;Kim, Chul Sung
    • Journal of the Korean Physical Society
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    • v.73 no.11
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    • pp.1708-1711
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    • 2018
  • The polycrystalline sample of $Ba_2Co_{1.5}Mg_{0.5}Fe_{11.88}Ga_{0.12}O_{22}$ Y-type hexaferrite, doped with Ga-cation, was prepared by using the solid-state reaction method. The crystalline structure of sample was investigated by x-ray diffractometer (XRD), and the magnetic properties of sample were measured by vibrating sample magnetometer (VSM), and $M{\ddot{o}}ssbauer$ spectrometer. The crystal structure of prepared sample was determined to be rhombohedral with space group R-3m. From the temperature dependence of the magnetization curves under 100 Oe between 4.2 and 740 K, two temperature-dependent magnetic transitions occurred in the $Ba_2Co_{1.5}Mg_{0.5}Fe_{11.88}Ga_{0.12}O_{22}$ sample. $M{\ddot{o}}ssbauer$ spectra of the sample were analyzed at various temperatures ranging from 4.2 to 620 K, and the $Ba_2Co_{1.5}Mg_{0.5}Fe_{11.88}Ga_{0.12}O_{22}$ sample showed abrupt changes in $H_{hf}$ and $E_Q$ at 200 K, indicating the spin transition effect. We have also determined the magnetic transition temperature $T_C$, in addition to the temperature dependent magnetization and ZVC measurements.

A Relativistiv Configuration Interaction Method Using Effective Core Potentials with Spin-Orbit Interactions

  • 김명청;이상연;이윤섭
    • Bulletin of the Korean Chemical Society
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    • v.16 no.6
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    • pp.547-552
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    • 1995
  • As an extension to the Kramers' restricted Hartree-Fock (KRHF) method [J. Comp. Chem., 13, 595 (1992)], we have implemented the Kramers' restricted configuration interaction (KRCI) program in order to calculate excited states as well as the ground state of polyatomic molecules containing heavy atoms. This KRCI is based on determinants composed of the two-component molecular spinors which are generated from KRHF calculations. The Hamiltonian employed in the KRHF and KRCI methods contains most of all the important relativistic effects including spin-orbit terms through the use of relativistic effective core potentials (REP). The present program which is limited to a small configuration space has been tested for a few atoms and molecules. Excitation energies of the group 14 and 16 elements calculated using the present KRCI program are in good accordance with the spectroscopic data. Calculated excitation energies for many Rydberg states of K and Cs indicate that spin-orbit terms in the REP, which are derived for the ground state, are also reliable for the description of highly excited states. The electronic states of the polyatomic molecule CH3I are probed from the molecular region to the dissociation limit. Test calculations demonstrate that the present KRCI is a useful method for the description of potential energy surface of polyatomic molecules containing heavy atoms.

Properties of thermally stimulated current of PAAS thin film using spin coating method (Spin coating한 polyamic acid alkylamine salt(PAAS) 박막의 열자격 전류 특성)

  • Lee, H.S.;Lee, S.Y.;Lee, W.J.;Kim, T.W.;Kang, D.Y.
    • Proceedings of the KIEE Conference
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    • 1996.07c
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    • pp.1719-1721
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    • 1996
  • This paper describes the thermally stimulated current(TSC) of PAAS spin coated film and the electrical properties of pre TSC measurement and after TSC test specimens. The TSC measurement were performed from room temperature to about $280^{\circ}C$ and the temperature was increased by $5^{\circ}C/min$ automatically. It shows that two peaks of TSC are observed at about $50^{\circ}C$ and about $160^{\circ}C$. Result of this measurement indicate that one peak; $50^{\circ}C$ is from alkyl group; other peak at $160^{\circ}C$ is due to alkyl and C-O group of PAAS. Addition to larger peak at about $160^{\circ}C$ is due to dipolemoment of PAAS film. This result is proved by DSC measurement of PAAS film. The electrical properties of pre and after TSC were measured by currant-voltage(l-V) characteristics. The current-voltage characteristics after TSC specimens are increased the conductivity. The electrical properties of pre-after TSC measurement specimen is in the middle of imidization of PAAS. Because of this result a thermal imidization was performed at $300^{\circ}C$ for 1 hour.

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Electron Spin Resonance of an Irradiated Single Crystal of L-alanine (인체 등가물질에 대한 방사선 조사)

  • 한영환;권수일
    • Progress in Medical Physics
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    • v.4 no.1
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    • pp.41-53
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    • 1993
  • The electron spin resonanec of sigle crystals of L-alanine have been observed at T=300K, 100K and analyzed for different orieantations of the crystal in the magnetic field and at microwave frequency X-band. The stable free radical profuced by the irradiation is proved to be of the form CH$_3$CHR, where R is a group which has no nuclei with detectable coupling A notable dependence on temperature of the absorption was observed in the range from 1100K to 2l0K. It was concluded that the reorietation of the methy group of the radical H$_3$CCHR is quenched at low temperature.

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The Effect of Upper Extremity Usage and Length of Training to the Function of Dance Turn (상지 이용 유무와 훈련 기간이 무용 회전 동작의 기능에 미치는 영향)

  • Park, Yang-Sun;Lim, Young-Tae
    • Korean Journal of Applied Biomechanics
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    • v.17 no.1
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    • pp.175-184
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    • 2007
  • The first purpose of this study was to compare kinematic variables during spinning motion with or without upper extremity and identify the most effective spinning method. The second purpose of this study was to compare functional difference between novice and elite dancers with the term of training. Ten experienced female dancers and ten novices were recruited as subjects for this study. Elite group was asked to perform turn motion with three types of upper extremity. Novice group has taken training of spotting technique for five weeks. Four Falcon HiRES cameras were used to analyze kinematic variables including head angular velocity and CG displacement during spinning. These data were sampled before training, after 3-week, and 5-week of training. Eight different events in two consecutive turns were defined for statistical comparison. One-way ANOVA was performed to compare among the kinematics of turning motion with three types of upper extremity. Independent t-test also used to compare kinematics between elite and novice at three different length of training. As results, spinning with both arm increased angular velocity and stability compared to the turning motion with one arm or with arm strapped and found out that the turn with both arm was the most effective way of spin. Also, for novice dancers, three weeks of training were needed to complete spinning motion.

Structural and Electrochemical Properties of Spin Coated LiCoO2 Cathode Thin Film in Lithium Secondary Batteries (스핀코팅법에 의한 리튬 2차전지용 산화물 양전극 LiCoO2 박막의 구조 및 전기화학적 특성에 대한 연구)

  • Gang, Seong-Gu;Yu, Gi-Cheon
    • Journal of the Korean Chemical Society
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    • v.50 no.3
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    • pp.243-246
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    • 2006
  • The LiCoO2 thin films were prepared on the Pt/Ti/SiO2/Si substrate by spin coating using citrate sol. The citrate sol was spin-coated on substrate and dried at 380oC for 15 min. to evaporate the solvents and remove the organic materials. The as-deposited films were annealed at 750oC for 10 min. in air for crystallization. The X-ray diffraction patterns for the film have been indexed hexagonal system with space group R3m. The active area of LiCoO2 films for electrochemical test was about 11cm2. A Li foil and 1M LiClO4 in propylene carbonate(PC) and ethylene carbonate(EC) (1:1)were used as an anode and an electrolyte, respectively. The galvanostatic charge-discharge test was carried out at constant current density ranging from 5 A/cm2 in the voltage window between 4.2 and 3.0 V. The first discharge capacity of the film is 0.35Ah/cm2-m. The cycling behavior of the LiCoO2 film is also reported.

Development and Analysis of Graphene Oxide Thin Film Coating (산화그래핀 박막 코팅기술 개발 및 특성평가)

  • Cheon, Yeong Ah;Nam, Jin-Su;Son, Kyung Soo;Im, Young Tae;Ahn, Won Kee;Chung, Bong Geun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.39 no.5
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    • pp.463-469
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    • 2015
  • In this study, we synthesized graphene oxide and developed novel spin-spray coating technology. The graphene oxide thin film was uniformly coated on amine-functionalized glass surfaces using spin-spray coating technology. We also stacked up to four layers of graphene oxide on glass substrates in a uniform manner. From the results, we infer that this spin-spray coating of graphene oxide thin film could be a powerful tool for various electronic display coating applications.

Implementation and Balancing Control of One-Wheel Robot, GYROBO (외바퀴 구동 GYROBO의 제작 및 밸런싱 제어 구현)

  • Kim, Pil-Kyo;Park, Junehyung;Ha, Min Soo;Jung, Seul
    • Journal of Institute of Control, Robotics and Systems
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    • v.19 no.6
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    • pp.501-507
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    • 2013
  • This paper presents the development and balancing control of GYROBO, a one wheeled mobile robot system. GYROBO is a disc type one wheel mobile robot that has three actuators, a drive motor, a spin motor, and a tilt motor. The dynamics and kinematics of GYROBO are analyzed, and simulation studies conducted. A one-wheeled robot, GYROBO is built and its balancing control is performed. Experimental studies of GYROBO's balancing abilities are conducted to demonstrate the gyroscopic effects generated by the spin and tilt angles of a flywheel.