• 대한치과의사협회지
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• 제55권12호
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• pp.850-860
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• 2017

Orthodontic treatment with premolar extraction is usually performed to correct bialveolar protrusion. These methods require the use of stiff rectangular working archwire which requires lengthy alignment and leveling before insertion. In this case report, interproximal reproximation was performed instead of extraction. To establish clearance between the archwire and resin domes fixing the archwire, an archwire was inserted into a water-soluble tube before fabricating resin domes. This tube is solved away by the saliva. During fabrication of resin domes, the archwire was deflected intentionally reflecting the displacement of teeth from their ideal position. This can be called as deflection-based bonding (DBB) technique. DBB is different from conventional method of positioning the brackets on its ideal position and then inserting an archwire to align the brackets. Because the orthodontic force of the archwire comes from its deflection from passive configuration, deflecting an archwire as needed can move the teeth more predictably than just bonding brackets on its ideal position. Also, areas with good alignment before orthodontic treatment can be maintained simply by not deflecting the archwire during bonding in these areas. After initial alignment, interproximal reproximation was performed to create 4.8 mm space in the maxillary arch and 4.2 mm space in the mandibular arch. These spaces were closed using orthodontic mini-implant anchorage thus retracting the maxillary incisors 4 mm posteriorly accompanied with 0.7 mm and 0.3 mm distal movement of right and left molars. By using interproximal reproximation and water-soluble tube with DBB, mild bialveolar protrusion was successfully treated without extraction.

• 대한족부족관절학회지
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• 제22권1호
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• pp.16-20
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• 2018

Purpose: To evaluate the clinical and radiographic results of surgical treatment for patients with sinus tarsi pain due to accessory talar facet impingement. Materials and Methods: Between July 2013 and July 2015, nine patients who underwent surgery for the accessory talar facet impingement were reviewed. The mean follow-up period was 18.6 months (12~36 months), and the mean age was 33.1 years (19~60 years). Previous trauma history, duration of symptom, and types of surgery were analyzed. The clinical results were evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score and visual analogue scale (VAS). Radiographic results were assessed using Meary's angle, calcaneal pitch angle, heel alignment angle, and heel alignment ratio. Results: All patients had evident trauma history prior to the initial symptom. The mean duration of symptoms was 25.6 months (6~120 months). Four patients received only accessory anterolateral talar facet (AALTF) excision, and four patients received medial sliding calcaneal osteotomy (MSCO). One patient underwent both AALTF excision and MSCO. The AOFAS ankle-hindfoot score was significantly improved from 73 (62~77) preoperatively to 93 (67~100) postoperatively. The VAS score was decreased from 6 (5~7) preoperatively to 1 (0~5) postoperatively. The Meary's angle and calcaneal pitch angle showed no significant difference after surgery. The heel alignment angle and ratio increased from $-3.6^{\circ}$ ($-10^{\circ}{\sim}5^{\circ}$) and 0.22 (-0.15~0.6) preoperatively to $2.8^{\circ}$ ($1^{\circ}{\sim}5^{\circ}$) and 0.42 (0.3~0.6) postoperatively, respectively. Conclusion: If there is persistent sinus tarsi pain in patients with hindfoot valgus, accessory talar facet impingement caused by AALTF could be considered as a cause of chronic sinus tarsi pain.

• 대한치과교정학회지
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• 제51권2호
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• pp.86-94
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• 2021

Objective: This study aimed to investigate the effect of micro-osteoperforations (MOPs) on external apical root resorption (EARR) during the initial orthodontic alignment phase of maxillary anterior crowding. Methods: Thirty patients (25 females, 5 males; mean age, 22.66 ± 3.27 years) who presented with moderate crowding of the upper labial segment and underwent extraction-based fixed appliance treatment were recruited. They were randomly allocated to receive adjunctive therapy with MOPs (n = 15) or treatment with fixed appliances only (control group; n = 15). EARR was measured from long-cone periapical radiographs taken at the start and the sixth month of treatment. A correction factor for the enlargement difference was used to calculate EARR. Data were analyzed with descriptive statistics and repeated-measures analysis of variance. Results: The mean root lengths of 168 teeth were measured and showed no statistically significant difference (p > 0.05) after six months of fixed appliance treatment in the MOP (mean difference [MD] = 0.13 mm; 95% confidence interval [CI] = -0.10-0.35) and control group (MD = 0.14 mm; 95% CI = -0.10-0.37). Most of the roots in the MOP and control groups (42.86% and 52.38%, respectively) showed only mild resorption. Less than 8% of the roots in both groups (7.14% in the MOP group and 4.76% in the control group) showed moderate resorption. Conclusions: Acceleration of orthodontic tooth movement with adjunctive MOPs therapy during the alignment phase does not exacerbate EARR in patients with moderate crowding of the upper labial segment in comparison with controls.

• 디지털융복합연구
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• 제19권2호
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• pp.481-488
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• 2021

본 연구의 목적은 농구동호인의 만성발목관절불안정성(CAI)에 따른 한발착지패턴의 변화를 확인하고 비교분석하고자 하였다. 현재 부산광역시에서 레크레이션 농구경기에 참여하고 있는 농구동호인 30명을 대상으로 국제발목협회에서 제공하는 CAI 표준 선정기준에따라 CAI집단 21명과 CON집단 9명으로 분류하였다. 한발착지패턴을 측정하기 위해 초기접촉 시점 및 무릎관절 최대 굽힘 시점에서 하지정렬과 관절 움직임을 측정하고 초기접촉 시점, 발꿈치접촉 시점 및 무릎관절 최대 굽힘 시점에서 앞정강근, 긴종아리근, 안쪽장딴지근 및 중간볼기근의 활성도를 측정하였다. 그 결과, 집단 간 단일 다리 드롭랜딩 시 하지정렬과 하지 근활성도는 유의한 차이를 보이지 않았다. 이런 결과는, CAI에 따라 한발착지패턴과 근활성도에 유의한 차이가 없다는 것을 보여주었다. 추후 연구에서는 CAI를 세부적으로 구분하고 경기포지션을 고려하여 움직임의 특성 및 기능적 요구의 차이를 반영해야 할 것으로 생각된다.

• 한국엔터테인먼트산업학회논문지
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• 제15권8호
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• pp.363-377
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• 2021

본 연구에서는 만성 파킨슨병 환자의 동적탄력튜빙 보행 훈련 (I, II)이 자세정렬, 보행, 삶의 질에 미치는 영향을 조사하였다. 총 3명의 만성 파킨슨병 환자를 모집하여 사례 연구를 시행하였다(Hoehn 및 Yahr 1-3단계 각 1명). 동적탄력튜빙 보행 훈련 (I 및 II)은 파킨슨병 환자에게 하루 30분, 주 5일, 5주 동안 25세션 적용되었다. 본 연구의 효과를 알아보기 위해, 자세정렬검사, 근 활성도검사, 보행분석 및 파킨슨병 환자의 삶의 질을 평가하였다. Dynamic tubing 보행 훈련(I, II) 중재 후 몸통 굽힘은 감소되었다. 또한 초기 접촉기(IC)에서 중간 디딤기(Mst)까지 보행 시 넙다리네갈래근, 뒤넙다리근, 앞정강근(TA)의 근 활성도가 증가하고 장딴지근의 근활성도가 감소하였다. 척추세움근(ES T12, L3)의 근활성도는 H&Y I, III 단계에서 증가하고 H&Y II 단계에서 감소하였다. 압력 중심(COP) 매개변수인 보행선의 길이, 한 발 지지선, 앞/뒤 위치, 좌우대칭 값이 개선되었다. 시공간 보행 매개변수인 보폭, 보폭, 의 속도는 증가하고 분당걸음수는 감소되었다. 나아가 파킨슨 병 환자의 삶의 질도 개선되었다. 이러한 연구 결과를 바탕으로 동적탄력튜빙 보행 훈련 (I 및 II)은 약물 내성이 절반으로 감소된 5년 이상된 만성 파킨슨병 환자의 자세, 보행, 삶의 질을 개선하기 위한 새로운 접근 방식으로 적용될 수 있을 것이다.

• Smart Structures and Systems
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• 제18권4호
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• pp.801-818
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• 2016

To estimate structural displacement, a visually servoed paired structured light system (ViSP) was proposed in previous studies. The ViSP is composed of two sides facing each other, each with one or two laser pointers, a 2-DOF manipulator, a camera, and a screen. By calculating the positions of the laser beams projected onto the screens and rotation angles of the manipulators, relative 6-DOF displacement between two sides can be estimated. Although the performance of the system has been verified through various simulations and experimental tests, it has a limitation that the accuracy of the displacement measurement depends on the alignment of the laser pointers. In deriving the kinematic equation of the ViSP, the laser pointers were assumed to be installed perfectly normal to the same side screen. In reality, however, this is very difficult to achieve due to installation errors. In other words, the pose of laser pointers should be calibrated carefully before measuring the displacement. To calibrate the initial pose of the laser pointers, a specially designed jig device is made and employed. Experimental tests have been performed to validate the performance of the proposed calibration method and the results show that the estimated displacement with the initial pose calibration increases the accuracy of the 6-DOF displacement estimation.

• 한국항행학회논문지
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• 제16권5호
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• pp.738-743
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• 2012

INS/GPS 통합 항법 필터는 주로 칼만 필터를 이용하여 구성되고 있다. 그러나 낮은 성능의 관성 센서를 이용한 INS/GPS 통합 항법 필터의 경우 센서 오차 레벨 등의 문제로 인해 정확한 방위각 정보의 제공이 곤란하며, 이로 인해 통합 필터를 구성하는 칼만 필터의 추정 성능이나 안정성을 보장할 수 없게 된다. 본 논문에서는 칼만 필터와 파티클 필터의 결합된 형태의 국지선형 파티클 필터를 이용하여 초기 방위각 오차를 극복할 수 있는 방법을 제시하였다.

• Bulletin of the Korean Chemical Society
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• 제34권11호
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• pp.3350-3356
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• 2013

Quasi-classical trajectory calculations have been carried out for the reaction H+HS by using the newest triplet 3A" potential energy surface (PES). The effects of the collision energy and reagent initial rotational excitation are studied. The cross sections and thermal rate constants for the title reaction are calculated. The results indicate that the integral cross sections (ICSs) are sensitive to the collision energy and almost independent to the initial rotational states. The ro-vibrational distributions for the product $H_2$ at different collision energies are presented. The investigations on the vector correlations are also performed. It is found that the collision energies play a postive role on the forward scatter of the product molecules. There is a negative influence on both the alignment and orientation of the product angular momentum for low collision energy at low energy region. Whereas the influence of collision energy is not obvious at high energy region.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.188-188
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• 2009

We have studied the optically compensated splay (OCS) mode using reactive mesogen (RM) monomer to reduce critical voltage, setting voltage and phase transition time from initial bend to splay state. Through the polymerization of UV curable RM monomer, the high pretilt angle from vertical alignment was formed at the surfaces. In this way, orientation of the LC with OCS mode can be achieved without setting voltage and improved electric characteristic.

• 한국정밀공학회지
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• 제16권2호통권95호
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• pp.164-175
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• 1999

If the camera plane is nearly parallel to the calibration board on which objects are defined, most of existing calibration approaches such as Tsai's radial-alignment-constraint method cannot be applied. Recently, for such an ill-conditioned case, Zhuang & Wu suggested the linear two-stage calibration algorithm assuming that the exact values of focal length and scale factor are known a priori. In this paper, we developed an iterative two-stage algorithm starts with initial guess fo the two parameters to determine the value of the others using Zhuang & Wu's method. In the second stage, the two parameters are locally optimized. This process is repeated until any improvement cannot be expected any more. The performance comparison between Zhuang & Wu's method and our algorithm shows the superiority of ours. Also included are the computational results for the effects of the distribution and the number of calibration points on the calibration performance.