• 제목/요약/키워드: and symmetric group

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이부편위자의 하악골상행지 경사에 관한 정모두부방사선학적 연구 (Posteroanterior cephalometric study of frontal ramal inclination in chin-deviated individuals)

  • 은춘선;황현식
    • 대한치과교정학회지
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    • 제36권5호
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    • pp.380-387
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    • 2006
  • 본 연구는 이부편위자의 정모두부방사선사진에서 하악골상행지 경사도의 좌우 차이를 알아봄으로써 교정환자의 임상검사 시 비대칭 진단에 도움이 되고자 시행되었다. 뚜렷한 이부편위를 보이는 성인 30명을 이부편위군으로, 좌우 대칭적인 외모를 보이는 성인 30명을 대조군으로 선정하여 정모두부방사선사진을 촬영한 후 하악골상행지 경사도를 측정하고 좌우 차이를 산출, 비교 분석한 결과, 대조군의 경우 좌우 차이를 보이지 않은 반면 이부편위자에서는 하악골상행지 경사도의 좌우 차이를 보였다. 이부편위자에서 비편위측의 하악골상행지의 경사도는 편위측에 비해 통계적으로 유의하게 큰 것으로 나타났으며, 하악골상행지 경사도의 좌우차이는 이부편위 정도 및 상악고경의 좌우차이와 통계적으로 유의한 순상관관계를 보였다. 이부편위자에서 하악골상행지 경사도의 좌우차이를 규명한 본 연구 결과는 안면비대칭 환자의 진단 시 하악골상행지 경사도에 대한 분석이 필요함을 시사하였다.

Three-dimensional morphometric analysis of mandibule in coronal plane after bimaxillary rotational surgery

  • Lee, Sung-Tak;Choi, Na-Rae;Song, Jae-Min;Shin, Sang-Hun
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제38권
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    • pp.49.1-49.9
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    • 2016
  • Background: The aim of this report is to present a new reference for aesthetic mandible surgery using three-dimensional cone-beam computed tomography-based treatment planning for orthognathic surgery which can be implemented in surgical planning and perioperative procedure. Methods: To make an objective standard for evaluating aesthetic mandibular outline, we make an aesthetic scoring criteria with consideration of asymmetry, broad mandibular border line, and prominent mandibular angle. Two maxillofacial surgeons and two orthodontists rated their aesthetical evaluation from 1 to 5. Experimental group consisting of 47 female and 38 male patients who had rotational orthognathic two-jaw surgery from 2010 to 2011 were chosen according to aesthetic scoring done by two maxillofacial surgeons and two orthodontists. A high aesthetic score (${\geq}16$) means the facial contour is symmetric, with no broad and narrow aesthetic mandible frontal profiles. Control A group consisted of ten female and ten male patients who had no orthognathic surgery experience and low aesthetic score (${\geq}10$). Control B group consisted of ten female and ten male patients who had no orthognathic surgery experience and had anaesthetic mandibular frontal profile and a high aesthetic score (${\geq}16$). The three-dimensional image of the patient was taken from dental cone-beam CT (DCT) scanning (experimental group and control A group: 6 months DCT after surgery, control B group: 1st visit DCT). Each DCT was reformatted to reorient the 3D image using 3D analyzing program (OnDemand3D, cybermed Inc, CA, USA). After selection of 12 landmarks and the construction of reoriented horizontal, vertical, and coronal reference lines, 15 measurements were taken in 3D analysis of frontal mandibular morphology. Afterwards, horizontal and vertical linear measurements and angular measurements, linear ratio were obtained. Results: Mean $Go^{\prime}_{Rt}-Me^{\prime}-Go^{\prime}_{Lt}$ angular measurement was $100.74{\pm}2.14$ in female patients and $105.37{\pm}3.62$ in male patients. These showed significant difference with control A group in both genders. Ratio of $Go^{\prime}_{Rt}-Go^{\prime}_{Lt}-Me^{\prime}$ length to some linear measurements (ratio of $Me^{\prime}-Cd^{\prime}_{Rt}Cd^{\prime}_{Lt}$ to $Me^{\prime}-Go^{\prime}_{Rt}Go^{\prime}_{Lt}$, ratio of $Me^{\prime}-Go^{\prime}$ to $Me^{\prime}-Go^{\prime}_{Rt}Go^{\prime}_{Lt}$, ratio of $Go^{\prime}_{Rt}-Go^{\prime}_{Lt}$ to $Me^{\prime}-Go^{\prime}_{Rt}Go^{\prime}_{Lt}$) showed significant difference with control A group in both genders. Conclusion: This study was intended to find some standard measurement of mandible frontal view in 3D analysis of aesthetic patient. So, these potential measurement value may be helpful for orthognathic treatment planning to have more aesthetic and perspective outcomes.

PNF 통합패턴 트레이닝이 하키선수들의 균형능력과 기능적 능력에 미치는 영향 (The effects of PNF combined patterns training on balance ability and functional ability of hockey players)

  • 안용덕;박종항
    • 디지털융복합연구
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    • 제11권11호
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    • pp.521-528
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    • 2013
  • 이 연구는 PNF 통합패턴 트레이닝이 하키선수들의 균형능력 및 기능적 능력에 미치는 영향을 알아보기 위해 연구대상자를 28명(대조군 14명과 실험군 14명)을 무선 배정하였으며, 실험군에서 총 12주간 주 3회, 하루 60분 동안 PNF 통합패턴 트레이닝을 실시하였다. 각 군은 사전, 6주 후, 12주 후에 전산화밸런스시스템을 이용하여 균형 능력을 측정하였으며, 기능적 능력은 카리오카, 셔틀런 능력을 측정하였다. 이상의 측정값을 통계학적 검정을 위해 반복측정분산분석으로 분석한 결과 다음과 같은 결론을 얻었다. 균형능력을 비교한 결과, 눈감고 양발로 지지하면서 선 자세에서 실험군의 전-후, 움직임 영역에서 유의한 차이가 나타났다(p<.05). 눈감고 오른발로 지지하면서 선 자세에서 실험군의 전-후, 내-외 및 움직인 영역 모두에서 유의한 차이가 나타났다(p<.05). 또한 동적 균형능력에서 실험군의 전-후, 움직인 거리에서 유의한 차이가 나타났다(p<.05). 운동수행관련 기능적 능력을 비교한 결과, 실험군의 셔틀런 능력에서 유의한 차이가 나타났다(p<.05). 이상의 결론을 통해 하키선수들에게 적용한 PNF 통합패턴의 대칭적인 트레이닝을 통해 하키선수들의 균형능력이 향상되었다는 것을 알 수 있었으며, 이를 통해 운동학적 기능이 향상된 것으로 판단되어 하키선수들의 경기력 향상을 위한 트레이닝 방법으로 적극 권장되어져야 된다고 사료된다.

안면비대칭 환자의 natural head position에 대한 정모두부방사선사진 연구 (Frontal Cephalogram Study on The Natural Head Position of Facial Asymmetry Patients)

  • 김현;황현식
    • 대한치과교정학회지
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    • 제30권5호
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    • pp.535-542
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    • 2000
  • 본 연구는 안면비대칭 환자의 natural head position(NHP)시 정면에서의 두부 또는 경추의 경사 정도를 알아봄으로써 교정환자의 임상검사시 비대칭의 진단에 도움이 되고자 시행되었다. 두드러진 전후방 골격 이상은 없으나 뚜렷한 좌우 안면비대칭을 보이는 성인 20명을 비대칭군으로, 좌우 대칭적인 외모와 비교적 정상교합을 보이는 성인 21명 을 대칭군으로 선정 한 다음 물방울 수평계를 이용하여 NHP 상태의 정모두부방사선사진을 촬영하고 투사도를 작성하였다. Crista galli와 anterior nasal spine을 연결한 선과 crista galli와 menton을 연결한 선이 이루는 각을 menton의 변위 정도로 정하고, 좌우 supra-orbital margin의 최상방점을 지나는 supra-orbital line과, 제1경추와 제4경추의 중심을 연결한 cervical line이 각각 true vertical line과 이루는 각을 계측한 다음 이들간의 상관관계를 비교 분석하여 다음과 같은 결과를 얻었다. 1. Supra-orbital line이 true vortical line과 이루는 각이 직각에서 벗어난 정도가 대칭군에 비하여 비대칭군에서 통계적으로 유의하게 크게 나타났다. 2. Cervical line이 true vertical line과 이루는 각은 통계적 유의차는 없었으나 비대칭군에서 더 큰 경향을 보였다. 3. 비대칭군에서 supra-orbital line이 true vortical line과 이루는 각이 직각에서 벗어난 정도는 menton의 변위 정도와 통계적으로 유의한 순상관관계를 보였다. 이상의 결과로 안면비대칭 환자는 menton의 변위를 보상하려는 방향으로 기울어진 NHP를 가지는 경향이 있음을 알 수 있었다.

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Positional symmetry of porion and external auditory meatus in facial asymmetry

  • Choi, Ji Wook;Jung, Seo Yeon;Kim, Hak-Jin;Lee, Sang-Hwy
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제37권
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    • pp.33.1-33.9
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    • 2015
  • Background: The porion (Po) is used to construct the Frankfort horizontal (FH) plane for cephalometrics, and the external auditory meatus (EAM) is to transfer and mount the dental model with facebow. The classical assumption is that EAM represents Po by the parallel positioning. However, we are sometimes questioning about the possible positional disparity between Po and EAM, when the occlusal cant or facial midline is different from our clinical understandings. The purpose of this study was to evaluate the positional parallelism of Po and EAM in facial asymmetries, and also to investigate their relationship with the maxillary occlusal cant. Methods: The 67 subjects were classified into three groups. Group I had normal subjects with facial symmetry ($1.05{\pm}0.52mm$ of average chin deviation) with minimal occlusal cant (<1.5 mm). Asymmetry group II-A had no maxillary occlusal cant (average $0.60{\pm}0.36$), while asymmetry group II-B had occlusal cant (average $3.72{\pm}1.47$). The distances of bilateral Po, EAM, and mesiobuccal cusp tips of the maxillary first molars (Mx) from the horizontal orbital plane (Orb) and the coronal plane were measured on the three-dimensional computed tomographic images. Their right and left side distance discrepancies were calculated and statistically compared. Results: EAM was located 10.3 mm below and 2.3 mm anterior to Po in group I. The vertical distances from Po to EAM of both sides were significantly different in group II-B (p=0.001), while other groups were not. Interside discrepancy of the vertical distances from EAM to Mx in group II-B also showed the significant differences, as compared with those from Po to Mx and from Orb to Mx. Conclusions: The subjects with facial asymmetry and prominent maxillary occlusal cant tend to have the symmetric position of Po but asymmetric EAM. Some caution or other measures will be helpful for them to be used during the clinical procedures.

청색 발광 가용성 PPV 공중합체의 합성 및 특성 (Synthesis and Characteristics of Blue Light Emitting Soluble PPV Copolymer)

  • 이경민;최병수
    • 한국전기전자재료학회논문지
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    • 제14권2호
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    • pp.145-151
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    • 2001
  • In this study, blue light emiting, soluble PPV copolymers were synthesized by Witting reaction and characterized. ITO/copolymer/Ca and ITO/copolymer/A1 structured light emitting diodes(LED) were fabricated and their I-V characteristics were examined. Copolymers showed $\pi$-$\pi$ transition in UV-Vis./NIR spectra. The PL and abosorption spectrum showed the symmetric vibration modes with mirror images which means that copolymers are highly aligned. By introducing aliphatic hydrocarbon group on polymer main chain, the solubility of copolymers was improved and no significant effects of substituent were observed. The band offset of copolymers are well suited as light emitting material for LED application than monomer or oligomer does. THe band offset of copolymers is ∼3eV in PL spectrum and the threshold voltages of ITO/copolymer/Ca and ITO/copolymer/Al structured LED 3V, 12V respectively. In the case of ITO/copolymer/Ca LED, it is believed that the amount of electrons and holes is well balanced and the recombination of opposite charges occurs easily because the work functions of Ca and Al electrodes are 2.9 and 4.3eV respectively and the difference in barrier height between polymer and electrode was small.

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3가지 형태의 백악질-골성 이형성증에 대한 증례보고 (3 TYPES OF CEMENTO-OSSEOUS DYSPLASIA : CASE REPORTS)

  • 김영란;김여갑;이백수;권용대;최병준
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제35권6호
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    • pp.481-485
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    • 2009
  • Cemento-osseous dysplasias are a group of disorders known to originate from periodontal ligament tissues and involve, essentially, the same pathological process. They are usually classified, depending on their extent and radiographic appearances, into three main groups. Periapical cemental dysplasia predominantly involves the periapical region of the anterior mandible. Florid cemento-osseous dysplasia presents with multifocal lesions in the tooth bearing or edentulous areas of the maxilla and mandible, often occurring bilaterally with symmetric involvement. Focal cemento-osseous dysplasia exhibits a single site of involvement in any tooth bearing or edentulous area of the mandible or maxilla, with the posterior mandible representing the most common site. We report the clinical, radiographic and histological findings of 3 types of cemento-osseous dysplasia with a review of literatures.

Multi-dimensional seismic response control of offshore platform structures with viscoelastic dampers (II-Experimental study)

  • He, Xiao-Yu;Zhao, Tie-Wei;Li, Hong-Nan;Zhang, Jun
    • Structural Monitoring and Maintenance
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    • 제3권2호
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    • pp.175-194
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    • 2016
  • Based on the change of traditional viscoelastic damper structure, a brand-new damper is designed to control simultaneously the translational vibration and the rotational vibration for platforms. Experimental study has been carried out on the mechanical properties of viscoelastic material and on its multi-dimensional seismic response control effect of viscoelastic damper. Three types of viscoelastic dampers with different shapes of viscoelastic material are designed to test the influence of excited frequency, strain amplitude and ambient temperature on the mechanical property parameters such as circular dissipation per unit, equivalent stiffness, loss factor and storage shear modulus. Then, shaking table tests are done on a group of single-storey platform systems containing one symmetric platform and three asymmetric platforms with different eccentric forms. Experimental results show that the simulation precision of the restoring force model is rather good for the shear deformation of viscoelastic damper and is also satisfied for the torsion deformation and combined deformations of viscoelastic damper. The shaking table tests have verified that the new-type viscoelastic damper is capable of mitigating the multi-dimensional seismic response of offshore platform.

INJECTIVE PARTIAL TRANSFORMATIONS WITH INFINITE DEFECTS

  • Singha, Boorapa;Sanwong, Jintana;Sullivan, Robert Patrick
    • 대한수학회보
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    • 제49권1호
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    • pp.109-126
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    • 2012
  • In 2003, Marques-Smith and Sullivan described the join ${\Omega}$ of the 'natural order' $\leq$ and the 'containment order' $\subseteq$ on P(X), the semigroup under composition of all partial transformations of a set X. And, in 2004, Pinto and Sullivan described all automorphisms of PS(q), the partial Baer-Levi semigroup consisting of all injective ${\alpha}{\in}P(X)$ such that ${\mid}X{\backslash}X{\alpha}\mid=q$, where $N_0{\leq}q{\leq}{\mid}X{\mid}$. In this paper, we describe the group of automorphisms of R(q), the largest regular subsemigroup of PS(q). In 2010, we studied some properties of $\leq$ and $\subseteq$ on PS(q). Here, we characterize the meet and join under those orders for elements of R(q) and PS(q). In addition, since $\leq$ does not equal ${\Omega}$ on I(X), the symmetric inverse semigroup on X, we formulate an algebraic version of ${\Omega}$ on arbitrary inverse semigroups and discuss some of its properties in an algebraic setting.

Cyclovoltametric Methods for the Ionization Potential and Electron Affinity of Iridium ppy Derivatives

  • Shin, Dong-Myung;Sohn, Byoung-Chung
    • 한국응용과학기술학회지
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    • 제20권2호
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    • pp.125-129
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    • 2003
  • The effects of molecular structure on the redox properties of the organic electroluminescent materials (Ir$(ppy)_3$ Ir$(m-ppy)_3$ Ir$(p-toly)_3$) were studied using cyclic voltammetry and spectroscopy. These iridium complexes show reversible oxidation and reduction on the electrode, which produce the symmetric cyclic voltammogram. It indicates that these materials are very stable under repetitive oxidation/reduction cycles. The electrochemically determined ionization potentia/electron affinity values are 5.4OeV/3.02eV for Ir$(ppy)_3$, 5.36eV/2.96eV for Ir$(m-ppy)_3$, and 5.35eV/2.97eV for Ir$(p-toly)_3$ from the SCE(Standard Calomel Electrode). The electrically determined band gaps are 2.38eV (521nm), Ir$(ppy)_3$, 2.4OeV (517nm), Ir$(m-ppy)_3$, and 2.38eV (521nm). Ir$(p-toly)_3$, which are similar with the optical band gaps. The position of methyl group on 2-phenylpyridine (ppy) effects do not influence much on the ionization potential, electron affinity, and band gap of Ir$(ppy)_3$ derivatives.