• Title/Summary/Keyword: center symmetry

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Change of gait pattern by ankle foot orthosis in stroke patients with foot drop (뇌졸중 환자의 단하지 보조기 착용 유무에 따른 보행 양상의 변화)

  • Oh, Jaegun;Park, Kee-eon;Jung, Byongjun;Lee, Ilsuk;Choi, Sanho;Lee, Sangkwan;Sung, Kang-keyng
    • The Journal of the Society of Stroke on Korean Medicine
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    • v.14 no.1
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    • pp.40-48
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    • 2013
  • ■ Objectives This study was designed to investigate the effects of an ankle foot orthosis(AFO) on gait of two hemiparetic stroke patients with foot drop. ■ Methods Gait of two hemiparetic stroke patients were analyzed during walking on the treadmill without or with AFO application. The spatiotemporal and center of pressure(CoP) intersection parameters of gait analysis were measured using a treadmill gait analysis system. ■ Results The AFO had positive effects on hemiparetic gait parameters; increasing cadence, increasing step length, decreasing step time, stride time, and lateral symmetry. ■ Conclusion Hemiparetic gait was improved by ankle foot orthosis.

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Case Study of 4-Bar Linkage KAFO in Person With Poliomyelitis (소아마비에서 4절 연쇄 장하지보조기 사례연구)

  • Kim, Jang-Hwan;Kwon, Oh-Yun;Yi, Chung-Hwi;Cho, Sang-Hyun;Cynn, Heon-Seock;Choi, Heung-Sik
    • Physical Therapy Korea
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    • v.20 no.1
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    • pp.18-27
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    • 2013
  • The purpose of this study was to compare the ring lock type knee-ankle-foot orthosis (KAFO) with newly developed 4-bar linkage KAFO on the gait characteristics of persons with poliomyelitis clinically. This 4-bar linkage is the stance control type KAFO which provide the stability during stance phase and knee flexion during swing phase. Two subjects participated in this study voluntarily. We provided the customized 4-bar linkage KAFO then asked the subjects to walk in level surface and stairs under the two different KAFO conditions. The characteristics of gait in the persons with poliomyelitis were evaluated using a 3D motion analysis system and force plate. Additionally 6 minute walk test for physiological cost index were conducted using pulse oximeter to measure the energy consumption. In the results of this study, the differences of 4-bar linkage KAFO compared with ring lock type KAFO are as follows: (1) Walking speed, stride length, and step length on level increased in subjects, (2) The gait symmetry was improved by generated knee flexion and decreased pelvic external rotation on level and stairs walking, (3) Decreased vertical excursion of center of mass and pelvic elevation during swing phase was decreased on level, (4) Knee extension moment, hip flexion moment, hip and knee internal rotation moment of non-braced limb were decreased on level walking, (5) Walking speed in 6-minute walk test was increased and physiological cost index was decreased. These findings indicate that 4-bar linkage KAFO compared with ring lock type KAFO is effective in enhancing pattern, endurance, and energy consumption in level surface and stairs walking.

Synthesis and Crystal Structure of Yttria-Stabilized Zirconia (이트리아를 첨가한 저코니아의 합성과 결정구조)

  • Kim, Won-Sa;Suh, Il-Hwan;Bak, Ro-Hak;Kim, Moon-Jib;Kim, Huhn-Jun;Lee, Chang-Hee;Kim, Yong-Che;Seong, Baek-Seok;Lee, Jeong-Soo;Shim, Hae-Seop;Kim, Yi-Kyung;Lee, Jin-Ho
    • Journal of the Korean earth science society
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    • v.18 no.6
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    • pp.553-558
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    • 1997
  • Colorless and transparent cubic zirconia($Zr_{0.73}Y_{0.27}O_{1.87}$) crystal has been synthesized by the Bridgman-Stock-bager method(also called Skull melting method). $Y_2O_3$ is used as stabilizer. The crystal shows a vitreous luster with a slight oily appearance. Under a polarizing microscope, it shows isotropic nature with no appreciable anisotropism. Mohs hardness value is measured to be $8{\sim}8\frac{1}{2}$ and specific gravity 5.85. Under ultraviolet light it shows a faint white glow. The crystal structure of yttria stabilized zirconia was determined, using single crystal X-ray diffraction techniques to be a cubic symmetry, space group $Fm\overline{3}m({O^5}_h)$ with $a=5.1552(5){\AA}$, $V=136.99(5){\AA}^3$, Z=4, and R=0.0488 for 29 unique reflections. Each zirconium atom is at the center of eight oxygen atoms situated at the corners of a surrounding cube and each oxygen atom is at the center of a tetrahedron of zirconium atoms. So a coordination of 8:4 holds in the structure.

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Analysis of Shear Stress Type Piezoresistive Characteristics in Silicon Diaphragm Structure (실리콘 다이아프램 구조에서 전단응력형 압전저항의 특성 분석)

  • Choi, Chae-Hyoung;Choi, Deuk-Sung;Ahn, Chang-Hoi
    • Journal of the Microelectronics and Packaging Society
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    • v.25 no.3
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    • pp.55-59
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    • 2018
  • In this paper, we investigated the characteristics of shear stress type piezoresistor on a diaphragm structure formed by MEMS (Microelectromechanical System) technology of silicon-direct-bonding (SDB) wafers with Si/$SiO_2$/Si-sub. The diaphragm structure formed by etching the backside of the wafer using a TMAH aqueous solution can be used for manufacturing various sensors. In this study, the optimum shape condition of the shear stress type piezoresistor formed on the diaphragm is found through ANSYS simulation, and the diaphragm structure is formed by using the semiconductor microfabrication technique and the shear stress formed by boron implantation. The characteristics of the piezoelectric resistance are compared with the simulation results. The sensing diaphragm was made in the shape of an exact square. It has been experimentally found that the maximum shear stress for the same pressure at the center of the edge of the diaphragm is generated when the structure is in the exact square shape. Thus, the sensing part of the sensor has been designed to be placed at the center of the edge of the diaphragm. The prepared shear stress type piezoresistor was in good agreement with the simulation results, and the sensitivity of the piezoresistor formed on the $2200{\mu}m{\times}2200{\mu}m$ diaphragm was $183.7{\mu}V/kPa$ and the linearity of 1.3 %FS at the pressure range of 0~100 kPa and the symmetry of sensitivity was also excellent.

Characterization of GaN epitaxial layer grown on nano-patterned Si(111) substrate using Pt metal-mask (Pt 금속마스크를 이용하여 제작한 나노패턴 Si(111) 기판위에 성장한 GaN 박막 특성)

  • Kim, Jong-Ock;Lim, Kee-Young
    • Journal of the Microelectronics and Packaging Society
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    • v.21 no.3
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    • pp.67-71
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    • 2014
  • An attempt to grow high quality GaN on silicon substrate using metal organic chemical vapor deposition (MOCVD), herein GaN epitaxial layers were grown on various Si(111) substrates. Thin Platinum layer was deposited on Si(111) substrate using sputtering, followed by thermal annealing to form Pt nano-clusters which act as masking layer during dry-etched with inductively coupled plasma-reactive ion etching to generate nano-patterned Si(111) substrate. In addition, micro-patterned Si(111) substrate with circle shape was also fabricated by using conventional photo-lithography technique. GaN epitaxial layers were subsequently grown on micro-, nano-patterned and conventional Si (111) substrate under identical growth conditions for comparison. The GaN layer grown on nano-patterned Si (111) substrate shows the lowest crack density with mirror-like surface morphology. The FWHM values of XRD rocking curve measured from symmetry (002) and asymmetry (102) planes are 576 arcsec and 828 arcsec, respectively. To corroborate an enhancement of the growth quality, the FWHM value achieved from the photoluminescence spectra also shows the lowest value (46.5 meV) as compare to other grown samples.

Graphic system analysis on the Chil Sung Hwa(seven stars picture) (칠성화(七星畵)의 그래픽체계 분석)

  • 나윤화
    • Archives of design research
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    • v.11
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    • pp.22-29
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    • 1995
  • I have to find standpoint of sight moulding of Chi I Sung Hwa(seven stars picture) analysis of graphic systems of a symbol sight native to our nation. And I will comprehend emotion of folkways by simple and graphic lines and colors in mathematical Grid of which ancestor had expressed in gauge moulding consciousness. This papers aim is to make a contribution to lead by on part of communication design. About structural analysis of pictorial graphic side. I) Mathematical thought of the Orient and space constitution are first basically the Orient expressed number notion of mathematics of unlimitedness and notion of zero so called space and empty second can analigize a diagonal expansion method by development of symmetry notion to basic the dual principle of the negative and positive by degrees development expressed space division method by direction notion. 2) About the proportion analysis it based the golden section globularity and in modern layout it takes vision center of position, after appointing the brow of sacred image of Chil Sung Hwa as center point of proportion and applied to the point proportion and so analigized the posibility of established. Rule in union of each elements and rule of forms about picture image. 3) Mathematical structure analysis to search a unified principle at the balanced arrangement and rule of forms it analigized the standard the rule of forms. it analigized the standard the rule of forms to body module of basic movement of protagonist and follower above basic forms of grid that is the basis of design system.

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Synthesis, Characterization and ESR Studies of New Copper(II) Complexes of Vicinal Oxime Ligands (Vicinal Oxime 리간드의 새로운 구리(II) 착물에 대한 합성, 특성 및 ESR 연구)

  • El-Tabl, Abdou S.;Shakdofa, Mohamad M.E.;El-Seidy, Ahmed M.A.
    • Journal of the Korean Chemical Society
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    • v.55 no.4
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    • pp.603-611
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    • 2011
  • Ethoxylacetyl oxime ligands [HL, (1) and $H_2L^1$, (3)] react with copper(II) acetate monohydrate yield octahedral and square planar complexes, respectively. The complexes have been postulated due to elemental analyses, IR, UVVis. spectra, magnetic susceptibility, conductivity and ESR spectra. Molar conductance of the complexes in DMF indicates a non-ionic character. The ESR spectra of [$(L)_2Cu(H_2O)_2$], (2) complex at room temperature and 77K are characteristic of an axial symmetry ($d_{x2-y2}$) with covalent bond character and have a large line width typical of dipolar interactions. However, [$(L^1)Cu$], (4) complex in the solid state showed spectra of marked broadening and loss of hyperfine splitting confirming spinexchange interactions between the copper(II) sites. The spectrum of the doped copper(II) complex at room temperature showed super-hyperfine splitting from coordinated nitrogen atoms and it has an axial type ($d_{x2-y2}$) with covalent bond character and an essentially square-planar arrangement around the copper(II) ion. The spectrum of [$(L^1)Cu$], (4) in frozen methanol at 77K was characteristic of the triplet state of a dimer species and the distance found between the two copper(II) centers was calculated and is equal to 4.8 ${\AA}$.

Kr Atoms and Their Chlustering in Zeolite A

  • Im, U Taek;Jang, Jang Hwan;Jeong, Gi Jin;Heo, Nam Ho
    • Bulletin of the Korean Chemical Society
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    • v.22 no.9
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    • pp.1023-1029
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    • 2001
  • The positions of Kr atoms encapsulated in the molecular-dimensioned cavities of fully dehydrated zeolite A of unit-cell composition Cs3Na8HSi12Al12O48 (Cs3-A) have been determined. Cs3-A was exposed to 1025 atm of krypton gas at 400 $^{\circ}C$ for four days, followed by cooling at pressure to encapsulate Kr atoms. The resulting crystal structure of Cs3-A(6Kr) (a = $12.247(2)\AA$, R1 = 0.078, and R2 = 0.085) has been determined by single-crystal X-ray diffraction techniques in the cubic space group Pm3m at $21(1)^{\circ}C$ and 1 atm. In the crystal structure of Cs3-A(6Kr), six Kr atoms per unit cell are distributed over three crystallographically distinct positions: each unit cell contains one Kr atom at Kr(1) on a threefold axis in the sodalite unit, three at Kr(2) opposite four-rings in the large cavity, and two at Kr(3) on threefold axes in the large cavity. Relatively strong interactions of Kr atoms at Kr(1) and Kr(3) with Na+ ions of six-rings are observed: Na-Kr(1) = 3.6(1) $\AA$ and Na-Kr(3) = $3.08(5)\AA.$ In each sodalite unit, one Kr atom at Kr(1) was displaced $0.74\AA$ from the center of the sodalite unit toward a Na+ ion, where it can be polarized by the electrostatic field of the zeolite, avoiding the center of the sodalite unit which by symmetry has no electrostatic field. In each large cavity, five Kr atoms were found, forming a trigonal-bipyramid arrangement with three Kr(2) atoms at equatorial positions and two Kr(3) atoms at axial positions. With various reasonable distances and angles, the existence of Kr5 cluster was proposed (Kr(2)-Kr(3) = $4.78(6)\AA$ and Kr(2)-Kr(2) = $5.94(7)\AA$, Kr(2)-Kr(3)-Kr(2) = 76.9(3), Kr(3)-Kr(2)-Kr(3) = 88(1), and Kr(2)-Kr(2)-Kr(2) = $60^{\circ}).$ These arrangements of the encapsulated Kr atoms in the large cavity are stabilized by alternating dipoles induced on Kr(2) by four-ring oxygens and Kr(3) by six-ring Na+ ions, respectively.

Study on the Structural and Transporting Property of Sr2Ru1-xCuxO4-y(0.0≤x≤0.5) (Sr2Ru1-xCuxO4-y(0.0≤x≤0.5) 화합물의 구조 및 전달 특성에 대한 연구)

  • Park, Jung-Chul
    • Journal of the Korean Chemical Society
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    • v.47 no.6
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    • pp.614-618
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    • 2003
  • $Sr_2Ru_{1-x}Cu_xO_{4-y}(0.0{\le}x{\le}0.5)$ compounds were prepared using a conventional solid state reaction. Based on the Rietveld refinements of X-ray diffraction results, it is revealed that $Sr_2Ru_{1-x}Cu_xO_{4-y}$ compounds are the single phases with K2NiF4 type tetragonal system in the range of 0=x=0.3, while the mixed phases of$Sr_2RuO_4$ and $Sr_2CuO_3$ in the range of $0.4{\le}x{\le}0.5$. By means of X-ray photoelectron spectroscopy, the valence states of Ru and Cu in $Sr_2Ru_{1-x}Cu_xO_{4-y}$, have been confirmed to 4+ and 2+, respectively. The bond length difference between $Ru-O_1 ({\times}4)\;and\;Ru-O_2 ({\times}2)\;in\;RuO_6$ octahedron is gradually decreased with increasing Cu content in $Sr_2Ru_{1-x}Cu_xO_{4-y}$, which results in the lower c/a ratio. So, it might be assured that the variation of local symmetry of $RuO_6$ octahedron is very closely related to the transporting property of $Sr_2Ru_{1-x}Cu_xO_{4-y}$ compounds. The behavior of resistivity discloses that the metallic property in $Sr_2RuO_4$ changes into the semiconducting one in proportion to the Cu content in $Sr_2Ru_{1-x}Cu_xO_{4-y}$.

Landscape Plants and Planting Characteristics of Three-Treasure Temples (삼보사찰의 조경식물 및 식재특성)

  • You, Ju-Han;Hong, Kwang-Pyo;Lee, Dong-Hun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.38 no.1
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    • pp.119-128
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    • 2010
  • The purpose of this study was to find a basic theory about Korean traditional planting pattern by analyzing a characteristic of planting and planted species in Haein, Tongdo and Songkwang Temples. The results are as follows. The planted species in three-treasure temples were 129 taxa; 57 families, 96 genera, 110 species, 12 varieties and 7 forma. The species related in Buddhism were Viburnum sargentii for. sterile, Hydrangea macrophylla for. otaksa and Musa basjoo. They are related in plant form and Buddhist ceremony. The results of forms were 34.1% in trees, 33.3% in shrubs, 3.9% in vine and 28.7% in herbage. The results of leaf fall were 56 taxa in broad-leaved deciduous trees, 27 taxa in broad-leaved evergreen trees and 14 taxa in needle-leaved evergreen trees. The native species were 32 taxa in Haein Temple, 27 taxa in Tongdo Temple and 44 taxa in Songkwang Temple. And the exotic species were 20 taxa, 28 taxa and 44 taxain the Haein, Tongdo and Songkwang Temples, respectively. In the results of analyzing the characteristics of planting, in the case of Haein Temple, Abies holophylla was linearly planted in Yiljumun, and Magnolia denudata was single planted in plant stairs of Haetalmun. In the case of plant stairs of Jeokmukdang, Cephalotaxus koreana was planted at regular intervals. In the case of Tongdo Temple, Celtis sinensis, Zelkova serrata and so forth were planted in Yiljumun, and Phyllostachys nigra was planted in form of screen planting in Youngsanjeon. The form of Hwanghwagak was a planting of symmetry in the center of a building, and the one of Daekwangmyyeongjeon was a mixed planting. The regular planting pattern was not shown in Yiljumun of Songkwang Temple. In the case of Dosungdang, Corunus officinalis was linearly planted in the west. In the case of Gwaneumjeon, Juniperus chinensis var. globosa and Camellia japonica were planted in symmetry. The old aged trees were planted in front of specimens planted in front of Daewoongbojeon.