• Title/Summary/Keyword: inclination angle (i)

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Study about the relationship between the amount of posterior impaction and the change of occlusal plane angle and incisor inclination in Le Fort I osteotomy (Le Fort I 골절단술에서 posterior impaction의 양과 occlusal plane angle, incisor inclination의 변화 관계에 관한 연구)

  • Kim, Bok-Joo;Kim, Min-Gu;Kim, Jung-Han;Kim, Chul-Hoon
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.36 no.5
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    • pp.375-379
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    • 2010
  • Introduction: In the management of dentofacial deformities, variable movement of the maxilla can be made possible by a Le Fort I osteotomy. Posterior impaction of the maxilla necessary for rotation of the maxillomandibular complex enhances the functions and esthetic results. In cases of posterior impaction of the maxilla, an increase in the figure of the occlusal plane angle and incisor inclination can occur. This study reports the relationship between the amount of posterior impaction and the change in the occlusal plane angle and incisor inclination in a Le Fort I osteotomy by preoperative and postoperative lateral cephalograms. Materials and Methods: Twenty patients who had undergone orthognathic surgery in Dong-A University Medical Center participated in this study. Lateral cephalometrics, within 3 weeks prior to surgery and 3 days after surgery, were used for analysis. Pre and postoperative measurements of the occlusal plane angle and incisal inclination based on the Frankfort horizontal (FH) plane were performed. X and Y were defined as the amount of vertical change in the upper incisor tip and the amount of vertical change in the upper first molar mesial cup tip through the operation. The amount of final posterior maxillary impaction was determined by subtracting Y from X, which is the difference in vertical height. According to the amount of posterior maxillary impaction, the change in the occlusal plane angle and incisal inclination was measured. Results: The average posterior maxillary impaction was 2.91 mm and the average change in the occlusal plane angle and incisal inclination was $6.54^{\circ}$after surgery. As a result, each mm of posterior maxillary impaction changed the occlusal plane angle and incisal inclination by $2.25^{\circ}$. Statistically, there was high significance. Two cases were observed: one with the same amount of posterior maxillary impaction performed on both the right and left showing $2.20^{\circ}$, and the other with a different amount of posterior maxillary impaction performed showing $2.35^{\circ}$. In this case, there was no significance difference between the two cases. Conclusion: Each mm of posterior maxillary impaction changes the occlusal plane angle and incisal inclination by an average of $2.25^{\circ}$. In posterior maxillary impaction, there was no significant difference in the amount of change in the occlusal plane angle and incisal inclination regardless of whether there was an equal amount of posterior maxillary impaction on both sides. This study is expected to help in the presurgical orthodontic preparation and presurgical treatment planning.

A CEPHALOMETRIC STUDY ON MESIODISTAL AXIAL INCLINATION OF POSTERIOR TEETH IN OPEN BITE AND DEEP BITE (개방교합과 과개교합에서 구치의 근원심 치축경사도에 관한 두부방사선계측학적 연구)

  • Jeon, Sang-Beom;Kim, Jin-Beom;Shon, Woo-Sung
    • The korean journal of orthodontics
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    • v.23 no.3 s.42
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    • pp.391-403
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    • 1993
  • For the purpose of investigating mesiodistal axial inclination of posterior teeth in normal occlusion group, open bite and deep bite group and investigating the correlationship between the axial inclination of posterior teeth and overbite of anterior teeth, a cephalometric study was performed on the subjects consisted of normal occlusion group(40), open bite group(71 : Angle's Class I, Class II, division 1 25, Class III 25) and deep bite group(64 : Angle's Class I 23, Class II, division 1 21, Class III 20). Mesiodistal axial inclination of posterior teeth to occlusal, mandibular and palatal plane were measured. The findings of this study were as follows : 1. Upper and lower posterior teeth were more mesially inclined to occlusal plane in open bite group than in deep bite group. 2. Lower posterior teeth were more mesially inclined in deep bite group than in open bite group in Angle's Class II, division 1 malocclusion but there were no significant differences in Angle's Class I and Class III malocclusion. 3. There was no significant correlationship between the axial inclination of posterior teeth to each plane and overbite of anterior teeth in open bite group. 4. There was a significant correlationship between the axial inclination of upeer and lower second premolar to occlusal plane and overbite of anterior teeth in Angle's Class I, Class II, division 1 and Class III malocclusion.

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Effects of Inclination of Enclosure and Partition on Natural Convective Heat Transfer in a Partitioned Enclosure (격판을 가진 밀폐공간내의 자연대류 열전달에 공간 및 격판의 경사가 미치는 영향)

  • Chung, I.K.;Song, D.J.;Kim, J.S.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.6 no.3
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    • pp.302-314
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    • 1994
  • The effects of the inclination of enclosure and partition on natural convective flow and heat transfer were investigated numerically. The enclosure was composed of the lower hot and the upper cold horizontal walls and the adiabatic vertical walls, and a partition was positioned perpendicularly at the mid-height of one vertical insulated wall. The governing equations are solved by using the finite element method with Galerkin method. The computations were performed with the variations of the partition length and Rayleigh number based on the temperature difference between two horizontal walls and the enclosure height with water(Pr=4.95). The effects of the inclination angle of enclosure and partition on the heat transfer within an enclosure were also studied. As the results, the increase of the inclination angle of enclosure rapidly raised the heat transfer rate, while the inclination angle for the maximum Nusselt number was retarded with the increase of the partition length and the decrease of the heat transfer rate became larger in proportion to the increase of the partition length. The Nusselt number obtained by the inclination of partition was smaller than that of the inclination of enclosure. However, the difference of the heat transfer rates was considerably decreased at the longer partition lengths and the trends for the variation of the average Nusselt number were more similar with that of the inclination of enclosure. The upward oriented partition increases the convective heat transfer distinctly in contrast to that of the inclination of enclosure as the partition length increases.

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Study on development of Solar Collector using Oscillating Capillary Tube Heat Pipe (진동세관형 히트파이프를 이용한 태양열 집열기 개발에 관한 기초연구(I);작동유체의 내부 충진율과 경사각도의 영향)

  • Kim, Tae-Hoon;Kim, Jong-Soo;Ha, Soo-Jung;Im, Yong-Bin
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.1394-1399
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    • 2004
  • Recently solar energy is representative in the technology development and spread of alternative energy. Specially in condition of solar collectors, they have had very various shape. This paper reports experimental study about the application of Oscillating Capillary Tube Heat Pipe to flat-plate solar collector. In conclusion, overall temperature distribution of OCHP was investigated by charging ratio and inclination angle. Respective charging ratio is 15%, 20%, 40% and respective inclination angle is horizontal, $30^{\circ}$, $45^{\circ}$, $60^{\circ}$, perpendicular. As a result of experiment, charging ratio 20% heat pipe has shown the most uniform temperature distribution and also performance of heat transfer has been the best.

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Dynamic response of layered hyperbolic cooling tower considering the effects of support inclinations

  • Asadzadeh, Esmaeil;Alam, Mehtab;Asadzadeh, Sahebali
    • Structural Engineering and Mechanics
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    • v.50 no.6
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    • pp.797-816
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    • 2014
  • Cooling tower is analyzed as an assembly of layered nonlinear shell elements. Geometric representation of the shell is enabled through layered nonlinear shell elements to define the different layers of reinforcements and concrete by considering the material nonlinearity of each layer for the cooling tower shell. Modal analysis using Ritz vector analysis and nonlinear time history analysis by direct integration method have been carried out to study the effects of the inclination of the supporting columns of the cooling tower shell on its dynamic characteristics. The cooling tower is supported by I-type columns and ${\Lambda}$-type columns supports having the different inclination angles. Relevant comparisons of the dynamic response of the structural system at the base level (at the junction of the column and shell), throat level and at the top of the tower have been made. Dynamic response of the cooling tower is found to be significantly sensitive to the change of the inclination of the supporting columns. It is also found that the stiffness of the structure system increases with increase in inclination angle of the supporting columns, resulting in decrease of the period of the structural system. The participation of the stiffness of the tower in structural response of the cooling tower is fund to be dependent of the change in the inclination angle and even in the types of the supporting columns.

Binary Nature Revealed in Circumstellar Spiral-Shell Patterns

  • Kim, Hyosun;Hsieh, I-Ta;Liu, Sheng-Yuan;Taam, Ronald E.
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.56.1-56.1
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    • 2014
  • With the advent of high-resolution high-sensitivity observations, spiral patterns have been revealed around several asymptotic giant branch (AGB) stars. Such patterns can provide possible evidence for the existence of central binary stars embedded in outflowing circumstellar envelopes. It is, however, not generally recognized that the binary induced pattern, vertically extended from the orbital plane, exhibits a ring-like pattern with an inclined viewing angle. I will first review the binary-induced spiral-shell patterns on the AGB circumstellar envelopes with the effect of inclination angle with respect to the orbital plane, of which large inclination cases reveal incomplete ring-like patterns. I will describe a method of extracting such spiral-shell from the gas kinematics of an incomplete ring-like pattern to place constraints on the characteristics of the (unknown) central binary stars. This first success may open the possibility of connecting the ring-like patterns commonly found in the AGB circumstellar envelopes and in the outer parts of (pre-)planetary nebulae and pointing to the conceivable presence of central binary systems, which may give a clue for the onset of asymmetrical planetary nebulae.

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A STUDY ON THE MANDIBULAR MOVEMENT OF ANTERIOR OPENBITE PATIENTS (전치부 개교환자의 하악 운동에 관한 연구)

  • Koak Jai-Young;Kim Kwang-Nam;Chang Ik-Tae
    • The Journal of Korean Academy of Prosthodontics
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    • v.32 no.2
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    • pp.281-295
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    • 1994
  • It is very important for the ideal restorations of anterior openbite patients to record the mandibular movement and to harmonize mandibular movement with other organs in stomatognathic systems. This study was designed to compare the mandibular movement of anterior openbite patients with that of normal bite(Angle Class I) patients, to ascertain which components of mandibular movement have differences between two groups, and to use for occlusal treatment of mandibular movement. Saphon Visi-trainer Model 3(Tokyo Shizaisha Co. Japan) and Denar Pantronic(Denar Corp.,U.S.A.) were used to record mandibular movement. Pantronic survey was peformed by using an arbitrary hinge axis according to manufacturer's direction. Twenty-eight adult who have physiologically normal occlusion(Angle Class I) and are free of TM dysfunction were selected as a control group(Group 1). Fifteen adult who are anterior openbite patient and have not anterior guidance function and have posterior interference at protrusion were selected as a experimental group(Group 2). The results are as follows : 1. There was no statistically significant difference between the average immediate and progressive side shift of anterior openbite patients(0.54mm, $7.57^{\circ}$) and those of normal group(0.49mm, $5.96^{\circ}$). 2. The average protrusive and orbiting condylar inclination of anterior openbite patient$(30.87^{\circ},\;32.27^{\circ})$ were significantly lower than those of normal group$(36.11^{\circ},\;39.04^{\circ})$ (P<0.05). 3. In the results of Visi-trainer recordings, the mean for the maximum protrusion, the maximum laterotrusion, the angle of laterotrusion and the angle of protrusion in the horizontal trajectory between group 1 and 2 did not differ significantly. 4. The mean for the angle of protrusion, the maximum opening in the frontal trajectory, the ICP-RCP(A-P) distance and the angle of protrusion in the sagittal trajectory differ significantly(P<0.05). 5. The significant correlation was found between orbiting condylar inclination and protrusive condylar inclination.

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ROENTGENOCEPHALOMETRIC STUDY ON CRANIOFACIAL MORPHOLOGY OF DEEPBITES (과개교합자의 악안면 형태에 관한 두부 X-선사진 계측학적 연구)

  • Kim, Hee-Jeong;Nahm, Dong-Seok
    • The korean journal of orthodontics
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    • v.23 no.3 s.42
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    • pp.341-358
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    • 1993
  • This study was investigated to evaluate the morphologic characteristics of deepbite tendency as multiple factors. The subjects consisted of 60 control subjects(male 25, female 35) and 137 deephite patients(68 male, 69 female). The deepbite group was composed of 4 subgroups(Class I 44, Class II div. 1 40, Class II div. 2 13, Class III 40). The mean age was 21.57 year for the control group 21 year for deepbite group lateral cephalograph in centric occlusion were taken, traced, and digitized for each subject. The statistically computerized analysis was carried out with SAS program. The results were as follows ; 1. In deepbite group, saddle angle is lesser than that of normal group. 2. The vertical dysplasia is prominent on anterior lower face and is closely related with mandibular form and inclination. 3. Without consideration of sagittal relationship, the dental factors such as curve of Spee, interincisal angle, U1 to upper lip length were prominent in the deepbite group. 4. Although there were individual variances in the perioral soft tissue profile, the lip presented more protruded pattern. 5. There was no significant difference in hyoid bone position and inclination between normal and deepbite group. 6. The multivariate discriminant analysis between normal and Class I deepbite group showed that curve of Spee, AB-MP angle, interincisal angle, articular agnle were critical in the determination of deepbite as multiple factors.

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A Convergent Investigation on Flow Analysis by Type of Turbine Blade of Fluid Clutch (유체클러치 터빈 날개의 유형별 유동해석에 대한 융합연구)

  • Oh, Bum-Suk;Cho, Jae-Ung
    • Journal of the Korea Convergence Society
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    • v.11 no.3
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    • pp.195-200
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    • 2020
  • In this study, the flow analyses were performed on the fluid clutch turbine blade shapes of models 1, 2 and 3, with eight turbine blades tilted at 45 °, 40 °, and 35 ° angles on the propulsion shaft, respectively. The larger the angle of inclination on the propulsion shaft, the higher the flow pressure among the flow models after the back of the turbine blades. On the other hand, the smaller the angle of inclination on the propulsion shaft of the turbine wing, the lower the flow rate. It can be seen that the smaller inclination angle of the turbine blade surface on the propulsion shaft, i.e., the wing shape close to perpendicular to the flow of fluid, is more suitable for efficiently connecting and disconnecting the fluid clutch. By applying the flow analysis by type of turbine blade of fluid clutch,the study result at this paper is considered to be favorable as the convergent research material which can apply the aesthetic design.

A STUDY ON POSITIONAL CHANCE OF THE HYOID BONE BEFORE AND AFTER ACTIVATOR THERAPY IN ANGLE'S CLASS III MALOCCLUSION PATIENTS (Angle씨 III급 부정교합 환자중 Activator사용 전후의 설골의 위치 변화에 관한 연구)

  • Koh, Sang-Duk;Cha, Kyung-Suk
    • The korean journal of orthodontics
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    • v.24 no.4 s.47
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    • pp.827-839
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    • 1994
  • This study was conducted to assess the positional changes of hyoid bone following the use of activator in Angles class III malocclusion patients with functional factors. For this study, 40 Angle's class I patients and 40 Angle's class III patients, totally 80 subjects were used. They are all in Hellman's dental age IIIB-IIIC ranges. In lateral cephalogram to compare Angle's class I group and Angle's class III group, and the positional changes of the hyoid bone before and after the use of activator in Angle's class III malocclusion group. The results were obtained as follows; 1. Comparison of Angle's class I group and Angle's class III group. In comparison to Angle's class I group, hyoid bone is more anteriorly and superiorly positioned in Angle's class III group. The hyoid bone showed reverse inclination to the mandibular plane in Angle's class III malocclusion group. 2. Comparison of the hyoid positional change before and after use of Activator in Angle's class III malocclusion group. The hyoid bone is displaced posteriorly and inferiorly in vertical relationship. The hyoid bone also showed counter-clockwise rotation. 3. No statistical difference was found between after Activator use data of Angle's class m malocclusion group and Angle's class I group. It is concluded that the hyoid bone in Angle's class III malocclusion group changed its position, similar to Angle's class I malocclusion group.

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