• 제목/요약/키워드: Angle deviation

검색결과 512건 처리시간 0.032초

일차 토순 수술후의 코입부위의 심미적 평가 제1보 코의 비대칭성 (NASAL ASYMMETRY AFTER PRIMARY OPERATIONS IN PATIENTS WITH UNILATERAL CLEFT LIP)

  • 민병일
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제16권3호
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    • pp.390-395
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    • 1994
  • The author evaluated the nasal asymmetry after primary operations in the patients with unilateral cleft lip using full face photographs. The results are as follows : 1. Nasal deviation angle is average 2.98+3.01 degree(ranged from 0 to 10 degree), significantly different from control group(p<0.05). 2. Nasal deviation angle is average 5.1% when inter-medial canthal distance is 100%, significantly different from control group(p<0.05). 3. Difference in nostril size between cleft and noncleft side is 2.1% when inter-medial canthal distance is 100%, significantly different from control group(p<0.05). 4. Nasal attractiveness analysis shows higher points in difference in nostril size, nasal deviation, nasal form in that order. 5. Nasal asymmetry after primary operations in the patients with unilateral cleft lip using full face photographs is related with Nasal deviation angle, Nasal deviation distance and Difference in nostril size between cleft and noncleft side.

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Effects of inter-implant distance on the accuracy of intraoral scanner: An in vitro study

  • Thanasrisuebwong, Prakan;Kulchotirat, Tharathip;Anunmana, Chuchai
    • The Journal of Advanced Prosthodontics
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    • 제13권2호
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    • pp.107-116
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    • 2021
  • PURPOSE. Several studies focused on the accuracy of intra-oral scanners in implant dentistry, but the data of inter-implant distances were not widely mentioned. Therefore, this study aimed to evaluate the effect of distance between two implants on the surface distortion of scanned models generated by intra-oral scanners. MATERIALS AND METHODS. Three models with the distances between two fixed scan bodies of 7, 14, and 21 mm were fabricated and scanned with a highly precise D900L dental laboratory scanner as reference models. Fifteen scans were performed with TRIOS3 and CEREC Omnicam intra-oral scanners. Trueness, precision, and angle deviation of the test models were analyzed (α=.05). RESULTS. There was a significant difference among inter-implant distances in both intraoral scanners (P<.001). The error of trueness and precision increased with the increasing inter-implant length, while the angle deviation did not show the same trend. A significant difference in the angle deviation was found among the inter-implant distance. The greatest angle deviation was reported in the 14-mm group of both scanners (P<.05). In contrast, the lowest angle deviation in the 21-mm group of the TR scanner and the 7-mm of the CR scanner was reported (P<.001). CONCLUSION. The inter-implant distance affected the accuracy of intra-oral scanner. The error of trueness and precision increased along with the increasing distance between two implants. However, the distortions were not clinically significant. Regarding angle deviation, the clinically significant angle deviation may be possible when using intra-oral scanners in the partially edentulous arch.

정지 비행에서의 곤충 날개 궤적에 따른 공기역학적 특성 (The effect of aerodynamic characteristics on the insect wing tip trajectory in hovering flight)

  • 조헌기;주원구
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.1441-1445
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    • 2008
  • Insect flight is adapted to cope with each circumstance by controlling a variety of the parameters of wing motion in nature. Many researchers have struggled to solve the fundamental concept of insect flight, but it has not been solved yet clearly. In this study, to find the most effective flapping wing kinematics, we conducted to analyze CFD data on fixing some of the optimal parameters of wing motion such as stoke amplitude, flip duration and wing rotation type and then controlled the deviation angle by fabricating wing tip motion. Although all patterns have the similar value of lift coefficient and drag coefficient, pattern A(pear-shape type) indicates the highest lift coefficient and pattern H(pear-shape type) has the lowest lift coefficient among four wing tip motions and three deviation angles. This result suggest that the lift and drag coefficient depends on the angle of attack and the deviation angle combined, and it could be explained by delayed stall effect.

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산업용 조정 피치형 축류송풍기의 성능예측에 관한 연구 (Study on Performance Prediction of Industrial Axial Flow Fan with Adjustable Pitch Blades)

  • 구재인;김창수;정진택;김광호
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2001년도 유체기계 연구개발 발표회 논문집
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    • pp.30-34
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    • 2001
  • In the present study, we studied the method of predicting the on-design and on-design point performance of axial flow fan with adjustable pitch blades. With the change of stagger angle of axial flow fan with adjustable pitch blade, flow rate and pressure can be changed. Because of this merit adjustable pitch fans are used in many industrial facility. When changing stagger angle or estimating the performance at a wide range of off-design condition, incidence angle changes greatly as the flow rate changes. Therefore, the deviation angle at the blade exit is estimated by the correlation considering the effects of blade design, incidence angle variation. In the loss model, we used known pressure loss model for blade boundary layer and wake, secondary flow, endwall boundary layer and tip leakage flow. The results of modified deviation angle model and experiment were compared for the usefulness of the modified model.

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회전자 자속 이탈각 추정을 이용한 유도전동기의 회전자 시상수 보상 (Rotor Time Constant Compensation of Induction Motor by Estimating Deviation Angle)

  • 차영길;정종진;김흥근
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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    • pp.264-267
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    • 1995
  • In indirect vector control, if the value or the rotor tine constant used in slip calculation is different from the actual rotor time constant because of the temperature rising and flux saturation level, model flux angle and actual flux angle is different so that the transient and steady state response is degraded. In this paper, flux deviation angle is calculated by using actual torque and reference torque, and this flux deviation angle is summed to slip angle, therefore rotor flux angle is always accurate and indirect vector control is satisfied.

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The accuracy of a 3D printing surgical guide determined by CBCT and model analysis

  • Ma, Boyoung;Park, Taeseok;Chun, Inkon;Yun, Kwidug
    • The Journal of Advanced Prosthodontics
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    • 제10권4호
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    • pp.279-285
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    • 2018
  • PURPOSE. The aim of this clinical study was to assess the accuracy of the implants placed using a universal digital surgical guide. MATERIALS AND METHODS. Among 17 patients, 28 posterior implants were included in this study. The digital image of the soft tissue acquired from cast scan and hard tissue from CBCT have been superimposed and planned the location, length, diameter of the implant fixture. Then digital surgical guides were created using 3D printer. Each of angle deviations, coronal, apical, depth deviations of planned and actually placed implants were calculated using CBCT scans and casts. To compare implant positioning errors by CBCT scans and plaster casts, data were analyzed with independent samples t-test. RESULTS. The results of the implant positioning errors calculated by CBCT and casts were as follows. The means for CBCT analyses were: angle deviation: $4.74{\pm}2.06^{\circ}$, coronal deviation: $1.37{\pm}0.80mm$, and apical deviation: $1.77{\pm}0.86mm$. The means for cast analyses were: angle deviation: $2.43{\pm}1.13^{\circ}$, coronal deviation: $0.82{\pm}0.44mm$, apical deviation: $1.19{\pm}0.46mm$, and depth deviation: $0.03{\pm}0.65mm$. There were statistically significant differences between the deviations of CBCT scans and cast. CONCLUSION. The model analysis showed lower deviation value comparing the CBCT analysis. The angle and length deviation value of the universal digital guide stent were accepted clinically.

정지 비행에서의 곤충 날개 궤적에 따른 공기역학적 특성 (The Aerodynamic Characteristics by the Insect Wing Tip Trajectory in Hovering Flight)

  • 조헌기;주원구
    • 대한기계학회논문집B
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    • 제33권7호
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    • pp.506-511
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    • 2009
  • Insect flight is adapted to cope with each circumstance by controlling a variety of the parameters of wing motion in nature. Many researchers have struggled to solve the fundamental concept of insect flight, but it has not been solved yet clearly. In this study, to find the most effective flapping wing dynamics, we conducted to analyze CFD data on fixing some of the optimal parameters of wing motion such as stoke amplitude, flip duration and wing rotation type and then controlled the deviation angle by fabricating wing tip motion. Although all patterns have the similar value of lift coefficient and drag coefficient, pattern A(pear-shape type) indicates the highest lift coefficient and pattern H(pear-shape type) has the lowest lift coefficient among four wing tip motions and three deviation angles. This result suggest that the lift and drag coefficient depends on the angle of attack and the deviation angle combined, and it could be explained by delayed stall and wake capture effect.

축류터빈에서 끝간격 유동에 의한 편향각과 압력손실의 모형 (Modeling of Deviation Angle and Pressure Loss Due to Rotor Tip Leakage Flow Effects in Axial Turbines)

  • 윤의수;박부룡;정명균
    • 대한기계학회논문집B
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    • 제22권11호
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    • pp.1591-1602
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    • 1998
  • Simple spanwise distribution models of deviation angle and pressure loss coefficient due to the tip leakage flow are formulated for use in association with the streamline curvature method as a flow analysis. Combining these new models with the previous deviation and loss models due to secondary flow, a robust streamline curvature method is established for flow analysis of single-stage, subsonic axial turbines with wide ranges of turning angle, aspect ratio and blading type. At the exit from rotor rows, the flow variables are mixed radially according to a spanwise transport equation. The proposed streamline curvature method is tested against a forced vortex type turbine as well as a free vortex type one. The results show that the spanwise variations of flow angle, axial velocity and loss coefficients at rotor exit are predicted with good accuracy, being comparable to a steady three-dimensional Navier-Stokes analysis. This simple and fast flow analysis is found to be very useful for the turbine design at the initial design phase.

굴삭기 상부작업체에서 틈새에 의한 버켓의 거동 편차에 대한 연구 (A Study on the Deviation of Bucket Behavior Considering the Effect of Clearance in the Excavator)

  • 신대영;강태곤
    • 드라이브 ㆍ 컨트롤
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    • 제16권4호
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    • pp.9-15
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    • 2019
  • Bucket trajectory is crucial regarding precision work with an excavator. In general, the bucket trajectory deviation is determined by the machining deviation of the frame, driving deviation of the driving hydraulic cylinder, clearance in the joints, and deformation of the structure. This paper investigated the relationship between the respective clearance in joints and the trajectory deviation of the bucket at the finishing work of the ditching for a 20-ton excavator. As a result, the larger the clearance, the larger deviation is increased at trajectory. However, it was found that the deviation of the rotation angle and displacement of the bucket was limited and the size of clearance does not affect closely on the contact angle of the pin shaft.

갑상선 암 환장서 기관지 편이 정도를 평가하는 방법의 연구 (Evaluation of Tracheal Deviation in Patients with Thyroid Cancer)

  • 유영삼
    • 대한기관식도과학회지
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    • 제16권2호
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    • pp.138-144
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    • 2010
  • Background: Tracheal deviations are encountered frequently in head and neck tumors especially in thyroid cancer. Dyspnea and stridor are symptom calling for surgery. The method of evaluation in tracheal deviation is not well established yet. This paper is aimed to suggest objective tools to evaluate tracheal deviation in relation to cervical vertebra. Material and Method: Ten cases of thyroid cancers were recruited retrospectively. Tracheal inner shadow and shape of cervical vertebra were reconstructed three dimensionally using 3D-doctor to compare position of trachea in relation to vertebral body. Extent of deviation was scored in relation to both lateral borders of vertebral body. Angles between trachea and spinous process were measured in axial CT and compared between study group and control group. Results: Deviation scores were statistically significant between study group (mean=1.1) and control group (mean=0) (p=0.0008). Deviation angles at maximal tumor size in study group (mean=160.3 Degrees) and deviation angles of control group (mean=177.1 Degrees) were statistically significant (p=0.0007). Angles at maximal deviation of three dimensional images ages in study group (mean=162.6 Degrees) and deviation angles of control group (mean=177.1 Degrees) were statistically significant (p=0.0089). Conclusion: Tracheal deviation can be evaluated using scoring of three dimensional images and measuring angle between trachea and vertebral spine.

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