• Title/Summary/Keyword: Inclination Angle

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A COMPARATIVE STUDY ON CRANIOFACIAL SKELETON BETWEEN ANGLE'S CLASS III MALOCCLUSION AND NORMAL OCCLUSION (Angle씨 제III급 부정교합의 두개 및 악안면 경조직에 관한 연구)

  • Park, Sei-Jin;Ryu, Young-Kyu
    • The korean journal of orthodontics
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    • v.17 no.1
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    • pp.63-72
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    • 1987
  • This is to investigate the difference between craniofacial correlation of Angle's class III malocclusion and that of normal occlusion. For this investigation, 28 adult males and famales, who have class III malocclusion, and 35 adult males and 46 adult famals., who have normal occlusion were selected to measure actual dimension of cranial base and to investigate ratio of various parts of maxillofacial skeleton against cranial base. Class III malocclusion were, also , classified based on SNA and SNB angle in normal range. Results were as follows. 1. In class III malocclusion, actual dimension of cranial base were appeared to be less than normal occlusion in both sex. 2. In class III malocclusion, values were less than normal occlusion in BN/ptm-A in both sex, but had no significance between two. 3. In class III malocclusion, ramal inclination, mandible inclination, BN/Go-Pog, lower genial angle were appeared to be greater. Thus, characteristic mandibular protrusive appearance of class III malocclusion was due to relative ratio and morphologic characteristic of mandibular body dimension against cranial base. 4. In class III malocclusion, upper incisors were labially tilted and lower incisors were lingually tilted compared to normal occlusion. 5. In typing of class III malocclusion, the most common type was found to be one which maxillas were in normal range, while mandibles were in protrusive tendency.

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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 STUDY ON THE VERTICAL DYSPLASIA IN THE SKELETAL CLASS III MALOCCLUSION (골격형(骨格型) III급(級) 부정교합자(不正咬合者)의 수직부조화(垂直不調和)에 관(關)한 연구(硏究))

  • Shin, Mun-Chang
    • The korean journal of orthodontics
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    • v.20 no.2
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    • pp.333-354
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    • 1990
  • This study was designed to analyse vertical dysplasia such as open bite or deep bite in persons with skeletal Class III malocclusion. The subjects consisted of 60 control patients, 40 Class III open bite patients and 40 Class III deep bite patients. The mean age was 19.8 years in the control group, 17.8 years in the Class III open bite group and 16.5 years in the Class III deep bite group. The results were as follows: 1. In Class III malocclusion patients, the characteristics of the vertical dysplasia are under the palatal plane. 2. In Class III malocclusion patients, the items showing the characteristics of the vertical dysplasia are mandibular plane angle, lower gonial angle, lower facial height, dental height & inclination of the upper first molar, interincisal angle, maxillary & mandibular occlusal plane angle. 3. In Class III malocclusion patients, LPFH/LAFH ratio shows the highest significance among the facial height ratios. 4. In Class III malocclusion patients, open bite group has a upward cant of maxillary occlusal plane & downward cant of mandibular occlusal plane. And deep bite group has a downward cant of maxillary occlusal plane & upward cant of mandibular occlusal plane. 5. In Class III malocclusion patients, the molar teeth of the open bite group are measially inclined and those of the deep bite group are upright.

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A Study of the Slim Design of Overhead Transmission Tower (가공송전철탑 경량화 설계에 관한 연구)

  • Lee, Jung-Won;Lee, Won-Kyo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.23 no.7
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    • pp.560-565
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    • 2010
  • This paper presents the design factor of an overhead transmission tower structure in order to reduce the tower weight. The behaviour of transmission tower structures are affected by the horizontal angle of the tower structure, the equivalent wind pressure group, the slope of the main post of the tower, the separation of the internode and the use of high-strength materials in their construction. Tower weight can be reduced by approximately 30% reduce weight by means of optimal design based on a consideration of all the above factors. In addition, the design of the foundation of the tower with the shear key installation to increase horizontal support together with a modified angle of inclination to the ground can reduce by about 37% the amount of concrete used during construction. The area of ground disturbed by the construction of the tower foundation can thus be reduced by approximately 33%. Therefore it is possible to build an environmently-friendly T/L tower with the mechanical properties of existing towers.

A Study on the Rectangular-Shaped Passive Row Piles in Inclined Sand-Ground by Model Test (경사모래지반의 사각형 수동 열말뚝에 관한 실험적 연구)

  • Bae, Jong-Soon;Kim, Ji-Seong;Kwon, Min-Jae
    • Journal of the Korean Geotechnical Society
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    • v.25 no.11
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    • pp.39-51
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    • 2009
  • This is a study on rectangular-shaped passive row piles in inclined sand-ground by model tests. The experiment controlled the angle of inclination of ground and induced the ground destruction. We also measured the behavior of row piles, by adjusting the shape, position and spacing of piles. As a result, we confirmed the earth pressure, the lateral resistance, and the effect of depressing on the ground variation working on passive pile. The effect of B-type pile of which the front width is wide is bigger than that of H-type pile of which the side width is wide. We can find out the failure angle of slope, the shared force of pile and soil by using the lateral resistance graph based on slope angle.

The Characteristics of Heat Transfer in a Channel with Wire-screen Baffles (와이어 스크린 배플이 설치된 채널에서의 열전달 특성)

  • Kim, W.C.;Ary, B.K.;Ahn, S.W.;Kang, H.K.
    • Journal of Power System Engineering
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    • v.13 no.2
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    • pp.11-17
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    • 2009
  • The heat transfer characteristics of flow through two inclined wire-mesh baffles in a rectangular channel were investigated experimentally with varying the mesh number of wire screens and inclination angle of the baffles. Two different types of wire meshes such as dutch and plain weaves, were used in this experiment. Three kinds of baffle plates with different mesh specifications in the dutch weave and four different kinds in the plain weave were manufactured. Baffles were mounted on bottom wall with varied angles of inclination. Reynolds number was varied from 23,000 to 57,000. It is found that the placement of inclined wire-mesh baffles in the channel affects the heat transfer characteristics by combining both jet impingement and flow disturbance. The wire screen modified the flow structure leading to a change in the heat transfer characteristics. The results show that the baffle plate with the most number of mesh (type SA) has the highest heat transfer rate.

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Development of Recliner Sensor for Car-Seat Using Wire Mechanism (와이어 기구를 이용한 자동차 시트 리크라이너 센서 개발)

  • Lee, Jeong-Wan;Jung, Won-Seok
    • Journal of Industrial Technology
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    • v.28 no.A
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    • pp.71-74
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    • 2008
  • Belt Integrated Seat(BIS) has many advantages compared to the existing seats. Due to the development of materials and manufacturing technology, BIS, which has been used restrictely in the past, has gone through a rapid growth. As a result, its advantages have gained attention and the possibility of replacing the existing seats has grown. The need to develop BIS has risen and presently joint development with associated industries is in progress. For its first goal, the development and research of Recliner sensor has been selected. Recliner sensor is an essential part of the BIS in which the belt is incorporated onto the seat. In seat-belts, there is an inclination sensor which locks the belt according to the angle of a car. Because the inclination sensor can change frequently depending on the back of seat, a device which can enhance the inclination sensor according to the angle of the back of seat. It is the Recliner sensor that play's this role. Studies on Recliner sensor within and outside Korea has not yet made a salient progress, and due to this fact, the joint development has made a start by benchmarking other company's products. Currently, in other to set the course of the development, a research in patents and various other information is being done. In addition, for the purpose of developing a product which will be compatible with the existing products, a prototype will be made and tested before a new product makes its launching on the market.

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The wave stability of the nonparallel natural convection flows adjacent to an inclined isothermal surface submerged in water at $4degC$ ($4degC$ 물에 잠겨있는 경사진 등온 벽주위 비평행 자연대류의 파형 안정성)

  • 황영규;장명륜
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.15 no.2
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    • pp.644-653
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    • 1991
  • A wave instability problem is formulated for natural convection flows adjacent to a inclined isothermal surface in pure water near the density extremum. It accounts for the nonparallelism of the basic flow and temperature fields. Numerical solutions of the hydrodynamic stability equations constitute a two-point boundary value problem which are accurately solved using a computer code COLSYS. Neutral stability results for Prandtl number of 11.6 are obtained for various angles of inclination of a surface in the range from-10 to 30 deg. The neutral stability curves are systematically shifted toward modified Grashof number G=0 as one proceeds from downward-facing inclined plate(.gamma.<0.deg.) to upward-facing inclined plate (.gamma.>0.deg.). Namely, an increase in the positive angle of inclination always cause the flows to be significantly more unstable. The present results are compared with the results for the parallel flow model. The nonparallel flow model has, in general, a higher critical Grashof number than does the parallel flow model. But the neutral stability curves retain their characteristic shapes.

Stress Intensity Factors for the Mixed Mode in Rotating Disks by Boundary Element Method (경계요소법에 의한 회전원판의 혼합 모우드 응력확대계수)

  • Park, S.O.
    • Journal of the Korean Society for Precision Engineering
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    • v.13 no.7
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    • pp.148-157
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    • 1996
  • This paper deals with the applicability of linear elastic fracture mechanics under centrifugal force. Stress intensity factors K are calculated as a function of the inclination crack of length 2a, the position at different angular velocities 1200rpm, 2400rpm and at different values of the inclination crack angle .phi. ( .phi. = 0 .deg. , 15 .deg. , 30 .deg. , 45 .deg. , 60 .deg. , 75 .deg. , 90 .deg. ) and are measured in models of rotation disks using a boundary element method. Especially, stress intensity factors $K_{l}$ and $K_{ll}$ obtained separately from the crack tip of the mixed mode, were used to further investigate the influence of $K_{l}$ and $K_{ll}$ on fracture in rotating disks. With the increase in the speed of rotation, the effect of K/ sub l/became larger where as that of $K_{ll}$ became small. For the increase in the inclination crack angle .phi. , a decrease in $K_{l}$ and an increase in $K_{ll}$ were observed.

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Ability to Maintain Postural Control while Standing on Perturbed Surfaces (바닥면의 교란에 따른 자세균형능력의 변화)

  • Park, Sung-Ha;Lee, Seung-Won
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.31 no.4
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    • pp.146-152
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    • 2008
  • This study was aimed to understand the effects of perturbed floor surface on human postural stability while standing. Ten subjects were asked to stand quietly on the surface with two angles of inclination ($0^{\circ}$ and $5^{\circ}$), two contamination conditions (dry and oil-contaminated), and three commercial floor materials (ceramic tile, coated wood, and vinyl tile). During each trial, a force plate with data acquisition systems was used to collect subject's center of pressure (COP) position. Measured COPs were then converted into the length of postural sway path in both subject's anterior-posterior (AP) and medio-lateral (ML) axis. Results showed that the length of sway path in ML axis was significantly affected by the angle of inclination and the type of floor material. The sway length was increased significantly at the inclination angle of $5^{\circ}$ and on the vinyl tile, respectively. The contamination condition, however, did not significantly affect the postural sway length in both AP and ML axis. The results imply that a proper treatment of floor surface and material is critical to preserving postural balance while standing.