• 제어로봇시스템학회논문지
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• 제8권6호
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• pp.524-532
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• 2002

This paper presents a new in-flight alignment method for an SDINS under large initial heading error. To handle large heading error, a new attitude error model is introduced. The attitude errors are divided into heading error and leveling errors using a newly defined horizontal frame. Some navigation error dynamic models are derived from the attitude error model for indirect feedback filtering of the in-flight alignment system. A Kalman filter with Position measurement is designed to estimate navigation errors as the indirect feedback filter Simulation results show that the proposed in-flight alignment method reduces the heading error very quickly from more than 40deg to about 5deg so as to apply a refined navigation filter. The total alignment process including leveling mode and navigation mode in addition to the proposed one allows large initial values not only in heading error but also in leveling errors.

• 한국임상수의학회지
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• 제39권3호
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• pp.100-106
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• 2022

The center of rotation of angulation-based leveling osteotomy (CBLO) has been introduced for the stabilization of cranial cruciate ligament rupture (CCLR) in small-breed dogs. This technique can be applied to the tibia without damaging its tuberosity. Although different designs of CBLO plates are available, tibial plateau leveling osteotomy (TPLO) plates have been still used for stabilization during CBLO. To the best of our knowledge, no studies have reported the effects of TPLO plates on the postoperative limb alignment after CBLO. Therefore, the present study (January 2020 to February 2021) aimed to compare the postoperative outcomes (postoperative tibial plateau angle [TPA] and tibial alignment) in patients receiving CBLO and TPLO plates during CBLO. Paired stifle joints (n = 16) were obtained from eight toy-breed cadaver dogs (mean weight, 4.4 kg) that underwent CBLO. The joints were randomly assigned to receive the CBLO (CBLO group) or TPLO plates (TPLO group). Pre-and postoperative radiographs were obtained, and the dissected tibiae were evaluated. The following postoperative parameters were compared to evaluate the surgical outcome: TPA, osteotomy location, mechanical medial proximal tibia angle, inter-segment gap, and tibial plateau translation. No significant differences were found in the postoperative alignment between the two groups. Therefore, TPLO plates may be considered as a viable alternative in toy-breed dogs undergoing CBLO.

• 대한치과교정학회지
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• 제28권4호
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• pp.591-600
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• 1998

본 연구는 교정치료를 목적으로 발치가 예정된 치아를 대상으로 임상적으로 매우 중요한 치료과정 중의 한 부분인 초기치아배열단계에서 다양한 기간과 크기의 교정력을 가하여 치아배열기간, 교정력의 크기,치아이동방향에 따라 치근표면에 일어나는 흡수와 회복 양상에 대한 정보를 얻기 위하여 시행되었다. 치료받지 않은 13개의 치아를 대조군으로 하고 교정치료계획상 제1소구치를 발거하기로 예정된 37개의 치아를 실험군으로 하여 20-450gm의 초기교정력을 가한 후 주사전자현미경적 관찰을 통하여 다음과 같은 결과를 얻었다. 1. 실험군 37개 중 22개의 치아($59.5\%$)에서 치근흡수가 발견되었다. 치근흡수는 최소실험기간인 3주군부터 나타났으며 흡수부위의 회복은 3개월군부터 나타났다. 2. 교정력의 기간 증가에 따라 치근흡수의 발생빈도가 증가하는 경향을 보였다. 3. 교정력이 클수록 상아질을 포함하는 홉수가 증가하는 경향을 보였다. 4. 치근 흡수의 부위는 하중 받는 부위와 일치하는 경향을 보였다. 5. 치근 흡수 부위의 면적과 가장 상관성이 높은 변수는 교정력의 크기였다.

• 제어로봇시스템학회논문지
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• 제14권6호
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• pp.595-602
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• 2008

In this paper, performance of the initial alignment for INS whose attitude is not leveled is investigated. Observability of the initial alignment filter is analyzed and estimation errors of the estimated state variables are derived. First, the observability is analyzed using the rank test of observability matrix and the normalized error covariance of the Kalman filter based on the 10-state model. In result, it can be seen that the accelerometer biases on horizontal axes are unobservable. Second, the steady-state estimation errors of the state variables are derived using the observability equation. It is verified that the estimates of the state variables have errors due to the unobservable state variables and the non-leveling tilt angles of a vehicle containing the INS. Especially, this paper shows that the larger the tilt angles of the vehicle are, the larger the estimation errors corresponding to the sensor biases are. Finally, it is shown that the performance of the 8-state model excepting the accelerometer biases on horizontal axes is better than that of the 10-state model in the initial alignment by simulation.

• 대한치과교정학회지
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• 제46권2호
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• pp.87-95
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• 2016

Objective: We evaluated the effects of tooth displacement on frictional force when conventional ligating lingual brackets (CL-LBs), CL-LBs with a narrow bracket width, and self-ligating lingual brackets (SL-LBs) were used with initial leveling and alignment wires. Methods: CL-LBs (7th Generation), CL-LBs with a narrow bracket width (STb), and SL-LBs (In-Ovation L) were tested under three tooth displacement conditions: no displacement (control); a 2-mm palatal displacement (PD) of the maxillary right lateral incisor (MXLI); and a 2-mm gingival displacement (GD) of the maxillary right canine (MXC) (nine groups, n = 7 per group). A stereolithographic typodont system and artificial saliva were used. Static and kinetic frictional forces (SFF and KFF, respectively) were measured while drawing a 0.013-inch copper-nickel-titanium archwire through brackets at 0.5 mm/min for 5 minutes at $36.5^{\circ}C$. Results: The In-Ovation L exhibited lower SFF under control conditions and lower KFF under all displacement conditions than the 7th Generation and STb (all p < 0.001). No significant difference in SFF existed between the In-Ovation L and STb for a 2-mm GD of the MXC and 2-mm PD of the MXLI. A 2-mm GD of the MXC produced higher SFF and KFF than a 2-mm PD of the MXLI in all brackets (all p < 0.001). Conclusions: CL-LBs with narrow bracket widths exhibited higher KFF than SL-LBs under tooth displacement conditions. CL-LBs and ligation methods should be developed to produce SFF and KFF as low as those in SL-LBs during the initial and leveling stage.

• 한국광학회지
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• 제4권1호
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• pp.15-21
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• 1993

본 연구에서는 설계제작된 KrF 엑시머 레이저 스텝퍼는 광원인 KrF엑시머 레이저, 조명광학계, 축소트영광학계, 정밀구동 웨이퍼 스테이지, 정렬시스템 및 이들을 제어하기 위한 제어계로 구성되어 있다. 본 실험에서 사용한 KrFdprtlaj 레이저는 밴드폭 3pm, 반복주파수 200Hz, 평균축력 3W이고, 5:1 투영렌즈는 N.A. 0.42, 전체 필드영역 $\varphi$21.2mm, 왜곡수차 최대 60nm 이하이다. 또한 정밀구동 웨이퍼 스테이지의 재현성과 해상도는 각각 $\pm$0.08$\mu\textrm{m}$/200mm(3 sigma), 100mm 반경에서 0.05 $\mu\textrm{m}$이다. 자동 초점 시스템은 $\pm$50$\mu\textrm{m}$범위에서 0.1$\mu\textrm{m}$의 해상도를 나타냈으며, 자동수평시스템은 120 arcsec 범위에서 larcsec의 해상도를 나타냈다. OFF-AXIS 정렬방식에서는 0.2$\mu\textrm{m}$의 해상도를 가지며, 두빔의 간섭을 이용한 새로운 TTL 정렬은 0.1$\mu\textrm{m}$의 해상도를 나타냈다. 스텝퍼 패턴 실험결과 SAL603레지스트를 사용하였을 때 웨이퍼의 노광후 열처리 $105^{\circ}C$, 60초에서 0.3$\mu\textrm{m}$ Lines and Spaces(L/S)까지 해상되었으며, 0.34$\mu\textrm{m}$ L/S에서 1$\mu\textrm{m}$의 초점심도를 얻을 수 있었다. 마스크 패턴과 레지스트 패턴의 선형성은 0.4$\mu\textrm{m}$ L/S가지 유지 되었다. 또한 XP-89131레지스트의 경우 노광후 열처리 $110^{\circ}C$, 60초에서 0.34$\mu\textrm{m}$ L/S까지 해상됨을 알수 있었다.

• 대한치과교정학회지
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• 제48권2호
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• pp.90-97
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• 2018

Objective: The aim of this study was to assess the analgesic effect of a single application of low-level laser therapy (LLLT) on spontaneous pain and pain on chewing after placement of initial archwires. Methods: Forty-two patients (26 women, 16 men) were randomly recruited for this split-mouth randomized clinical trial. Each patient received super-elastic nickel-titanium (NiTi) initial archwires (0.012, 0.014, 0.016, and 0.018-inch [in]) in the maxilla for leveling and alignment for an interval of 4 weeks between archwires. One side of the mouth was randomly designated as experimental, while the other side served as placebo. After insertion of each archwire, the experimental side was irradiated with a diode laser for 3 seconds each on 5 points facially and palatally per tooth, from the central incisor to first molar. On the placebo side, the laser device was held the same way but without laser application. A numerical rating scale was used to assess the intensity of spontaneous and masticatory pain for the following 7 days. The Mann-Whitney U test was used to compare pain scores between sides. Results: Patients in the LLLT group exhibited significantly lower mean scores for spontaneous pain after insertion of the initial two archwires (0.012-in and 0.014-in NiTi; p < 0.05), while there was no significant difference for 0.016-in and 0.018-in wires between the LLLT and placebo groups. LLLT significantly reduced chewing pain scores (p < 0.05) for all archwires. Conclusions: A single dose of LLLT considerably lessened postoperative pain accompanying the placement of super-elastic NiTi wires for initial alignment and leveling.

• 한국표면공학회지
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• 제52권5호
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• pp.239-245
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• 2019

To increase the throughput of tip-based nanolithography (TBN), one approach is to use a large array of such tips working in parallel. It is important to maintain co-planarity between the tip array and the writing surface. A slight misalignment can cause large discrepancies of contact force and feature sizes. We report a capacitive proximity sensor built-in with the TBN array for leveling an arrayed polymer pen array. The device allows alignment between an array of writing tips and the writing substrate without contact and contamination. The angular sensitivity of the sensor is $0.05^{\circ}$ for an array with maximum tip-to-tip separation of 100 mm.

• 한국임상수의학회지
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• 제39권3호
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• pp.93-99
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• 2022

The present study was performed to compare cranial tibial wedge osteotomy (CTWO) and tibial plateau leveling osteotomy (TPLO) through radiographic evaluation. The experiment was conducted with five cadaver dogs [mean (± SD) weight, 32.9 ± 4.1 kg; mean (± SD) age, 6 ± 2 years; three males and two females] euthanized for reasons unrelated to this study. The cadaver dogs consisted of German Shepherd (n = 3), Belgian Malinois (n = 1), and mixed breed (n = 1). CTWO and TPLO were carried out by the standard surgical method. Radiographic evaluation was performed by comparing several factors, including the flexion and extension angles, the anatomical mechanical axis angle (AMA-angle), tibial length, patellar height measurement using the Labelle-Laurin method, mechanical medial proximal tibial angle (mMPTA), mechanical medial distal tibial angle (mMDTA), and frontal plane alignment (FPA). Both the CTWO and the TPLO groups showed significantly increased flexion angles after surgery. Only the CTWO group had significantly increased extension angle. Although both groups showed significant decreases in the AMA-angle, the mechanical axis moved cranially against the anatomical axis only in the CTWO group. The patellar height was significantly lowered in the CTWO group. No significant differences were found in mMPTA, mMDTA, or FPA. In conclusion, radiographic comparison revealed more changes in CTWO group than in TPLO group.

• 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.