• Title/Summary/Keyword: Lateral Rotation

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Ectopic Eruption of transposed mandibular lateral incisors

  • Kim, Ga-Yeong;Kim, Seon-A
    • Journal of the Korean Academy of Esthetic Dentistry
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    • v.12 no.1
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    • pp.39-42
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    • 2003
  • Mandibular permanent lateral incisors showing bilateral transposition and ectopic eruption were seen beside deciduous first molars in a female aged 8yr 8month. Repositioning of the ectopic lateral incisor is difficult not only because of its distal displacement and severe rotation but also because of the potential development of transposition with the erupting canine. This paper is focused on the diagnosis of the ectopic eruption and advocates treatment with active orthodontic management at the early stage of mixed dentition, before the eruption of the permanent cuspid.

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Overturning Resistance of Plain Concrete Piers in OSPG Railroad Bridges

  • Rhee, In-Kyu;Park, Joo-Nam;Choi, Eun-Soo
    • International Journal of Railway
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    • v.3 no.1
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    • pp.1-6
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    • 2010
  • The steel plate-girder bridges with concrete gravity piers have possibilities of overturning by lateral inertial force which can be reproduced by sudden earthquake attack. This paper explores an overturning mechanism of existing concrete gravity pier onto the sandy soil in the event of lateral push-over load by in-situ experimental observation. The in-situ push-over experiment for pier with earth anchors between spread footing and rock beds exhibits a reasonable enhancement of ductility against overturning. In unanchored system, a flexural crack at cold joint of concrete pier is not developed because of the over-turning of the pier. This leads a global instability (rotation) of pier-footing system with relatively low stresses in pier itself. While a lateral load is persistently increased in anchored system, the successive flexural cracking failure at cold joint is observed even after the local shear failure of soil due to redistribution of stress equilibrium between soil and pier structure as long as a tensile action of anchor cable is active.

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Shear behavior of exposed column base connections

  • Cui, Yao
    • Steel and Composite Structures
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    • v.21 no.2
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    • pp.357-371
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    • 2016
  • Column base connections are critical components in steel structures because they transfer axial forces, shear forces and moments to the foundation. Exposed column bases are quite commonly used in low- to medium-rise buildings. To investigate shear transfer in exposed column base plates, four large scale specimens were subjected to a combination of axial load (compression or tension) and lateral shear deformations. The main parameters examined experimentally include the number of anchor rod, arrangement of anchor rod, type of lateral loading, and axial force ratio. It is observed that the shear resisting mechanism of exposed column base changed as the axial force changed. When the axial force is in compression, the resisting mechanism is rotation type, and the shear force will be resisted by friction force between base plate and mortar layer. The specimens could sustain inelastic deformation with minimal strength deterioration up to column rotation angle of 3%. The moment resistance and energy dissipation will be increased as the number of anchor rods increased. Moreover, moment resistance could be further increased if the anchor rods were arranged in details. When the axial force is in tension, the resisting mechanism is slip type, and the shear force will be resisted by the anchor rods. And the shear resistance was reduced significantly when the axial force was changed from compression to tension. The test results indicated that the current design approach could estimate the moment resistance within reasonable acceptance, but overestimate the shear resistance of exposed column base.

The Changes of Range of Motion of Lumbar Region and Muscle Activities of Lumbar Extensor During Trunk Motions Between Subjects With Low Back Pain and Healthy Subjects (만성요통환자와 정상인의 체간 운동시 요추 신전근의 근활성도와 관절운동범위의 변화)

  • Kim, Tae-Ho
    • Physical Therapy Korea
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    • v.13 no.2
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    • pp.61-69
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    • 2006
  • The purpose of this study was to compare the electromyography (EMG) activities of the lumbar extensor muscles during motion of trunk flexion-extension and compare range of motion (ROM) with a 3-dimensional motion analysis system of the lumbar region between subjects with chronic low back pain (CLBP) and healthy subjects during the trunk flexion-extension, trunk rotation and trunk lateral flexion cycle. Thirty CLBP subjects and thirty healthy subjects were included. We measured the root mean square (RMS) value of the lumbar extensor muscles from resting, standing, lumbar flexion and return position. The RMS ratio was normalized from maximal EMG activity of the lumbar extensor muscles during trunk motion. The results of this study showed that the RMS ratio of the lumbar extensor was significantly higher in CLBP subjects than healthy subjects during all of trunk motion (p<.05). The ratio of the highest RMS value during flexion and extension was higher in CLBP subjects than in healthy subjects (p<.05). The ROM of the lumbar region was significantly lower in CLBP subjects than healthy subjects during trunk flexion-extension, trunk rotation and lateral flexion cycle. The relationship between the RMS ratio for full lumbar flexion and the ROM of lumbar flexion was not correlated significantly. CLBP subjects have both decreased ROM of the lumbar region and higher muscle activities of the lumbar extensor muscle than healthy subjects.

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The Effects of Standing Posture Improvement Exercise to the Turning Round Movement in Patients with Parkinson Disease (기립자세 증진 운동이 파킨슨병 환자의 제자리 돌기 동작에 미치는 영향)

  • Kim, Joo-Hyoun;Hwang, Byong-Yong;Yoon, Hui-Jong
    • The Journal of Korean Physical Therapy
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    • v.19 no.5
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    • pp.21-28
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    • 2007
  • Purpose: The aims of this study was to evaluate the effects of shoulder lateral rotation and trunk extension exercises on standing posture improvement exercises using turning round in the patients with Parkinson's disease. Methods: For twenty-one patients with Parkinson's disease, shoulder lateral rotation and trunk extension exercises were performed for a total of three sets, ten times a set, three days a week for twelve weeks. To measure turning round, ink foot-print method was used. The number of steps and time were measured every week for before and after study (twelve weeks). Results: The results are as follows: Changes in steps and time on each week during twelve weeks showed significant differences, compared with before test(p<0.05). Conclusion: Standing posture improvement exercises can help perform turning round in the patients with Parkinson's disease.

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The Effects of Kinesiotaping Applied onto Erector Spinae and Sacroiliac Joint on Lumbar Flexibility

  • Shin, Do-Yun;Heo, Ju-Young
    • The Journal of Korean Physical Therapy
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    • v.29 no.6
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    • pp.307-315
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    • 2017
  • Purpose: The purpose of this study was to investigate the effects of kinesio taping on lumbar flexibility onto erector spinae and sacroiliac joint. Methods: Sixty healthy adults (male=36, female=24) participated in this study and were randomly assigned to the experimental group that received kinesio taping onto erector spinae and sacroiliac joint (n=30) or the control group that received X-letter placebo taping onto them (n=30). Lumbar flexibility (flexion, extension, lateral flexion, and rotation) was measured using back range-of-motion instrument (BROM) II before and after taping. Results: In the change of lumbar flexibility after taping in the experimental group, there were statistically significant difference in flexion, lateral flexion, and rotation (p<0.05), but there was no significant difference in extension. There was no significant difference in the change of lumbar flexibility after taping in the control group. Conclusion: In conclusion, kinesio taping onto erector spinae and sacroiliac joint improved the joint function. Kinesio taping may reduce the muscle tension and facilitate the circulation of tissue fluid. In light of these results, it is thought that the application of kinesio taping had influence on an increase in lumbar flexibility. Therefore, kinesio taping will be able to be used as the method of the prevention of pain and the treatment in the lumbar region.

A Study on the Behavior of Spheroid Configuration Bobbin (회전타원체 보빈 형상의 거동에 관한 연구)

  • Kang, Seung-Hee;Ahn, Sung-Ho;Rim, One-Kwon;Kim, Hye-Ung
    • Journal of the Korea Institute of Military Science and Technology
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    • v.13 no.5
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    • pp.717-724
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    • 2010
  • The initial trajectory of a spheroid configuration bobbin for precision guidance has been investigated by analyzing its aerodynamic load and six-degree-of-freedom motion. The effects of changes in the spheroidal head configuration, flow angle and lateral center-of-gravity offset are numerically studied using the commercial software "FLUENT". A wind tunnel test is also conducted to validate the numerical scheme and to examine effect of the Reynolds number on the flow around the bobbin. It is shown that the size of the separation bubble formed on the surface decreases significantly when the Reynolds number is varied between 110,000 and 140,000. At a zero flow angle, an oblate spheroidal head shows relatively moderate rotation while a prolate spheroidal head shows rapid rotation. The bobbin with a spherical head shape has little effect on the flow direction; however, the oblate bobbin is sensitive to the flow angle. The roll motion of the bobbin is greatly influenced by the lateral center-of-gravity offset and maximum dispersion is observed at half of the radius.

A LASER HOLOGRAPHIC STUDY ON THE INITIAL REACTION OF MAXILLOFACIAL COMPLEX TO MAXILLARY PROTRACTION (상악 전방견인시 악안면골의 초기반응에 관한 Laser Holography연구)

  • Kang, Hung Sok
    • The korean journal of orthodontics
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    • v.18 no.2
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    • pp.367-385
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    • 1988
  • In case of skeletal Class III malocclusion with underdeveloped maxilla, the extraoral orthopedic force for the stimulation of maxillary growth or anterior reposition of the maxilla has been used clinically for the improvement of facial skeletal relationship. The purpose of this investigation was to examine the initial reaction of maxillofacial complex to the maxillary protraction by using extraoral orthopedic force. The dried human skull was used and this investigation was done by means of double exposure holographic interferometry. The protraction forces placed on the canine or the first molar were parallel, $10^{\circ}$ downward, $20^{\circ}$ downward to the occlusal plane. Fringe pattern of each protraction condition was compared and analized. The results were as follows: 1. Each maxillofacial bone displaced saparately. 2. More displacement was shown at the area of the teeth and the alveolar bone. 3. A counterclockwise rotation of the maxilla wa decreased by downward protraction and especially 20 degree downward protraction from the canine showed least rotation. 4. On the zygomatic arch, outward bend was observed and this effect was decreased by downward protraction. 5. On the zygomatic bone, the counter clockwise rotation was increased by the downward protraction. 6. When maxillary expansion was applied at the same time, outward and upward displacement with counterclockwise rotation was observed on the maxilla. 7. The lateral pterygoid plate of sphenoid bone was affected by maxillary protraction.

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A Study on the Flexibility of Semi-Rigid Steel Frames under Lateral Loadings( I ) (횡하중을 받는 반강접 철골 골조의 유연도에 관한 연구( I ) -접합부 해석모형을 중심으로-)

  • KANG, Cheol Kyu;HAN, Young Cheol;LEE, Gag Jo
    • Journal of Korean Society of Steel Construction
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    • v.8 no.3 s.28
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    • pp.127-137
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    • 1996
  • Connections as basic elements and an integrated part of a steel frame has an effect on the frame's performance. Conventional analysis and design techniques are based on either idealized fixed or pinned conditions. In fact, the use of rigid or pinned connection model in steel frame analysis serves the purpose of simplifying the analysis and design processes, but all connections used in current pratice possess stiffness and transfer moment which fall between the extreme cases of fully rigid and ideally pinned. To predict the behavior of the semi-rigid steel frames, it is necessary to predict the moment-rotation behavior of the beam-to-column connections. In this research, prediction equation for moment-rotation behavior of the beam-to-column connection is suggested and the effect of design parameters has investigated. Prediction model, in a nondimensional form shows the moment-rotation characteristic for connections. It is composed of the curve fitting power function using standardization constant K and 4 parameter $KM_o$, ${\theta}_0$, b, n based on the pretest result about moment-rotation behavior of connection.

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SOFT TISSUE CHANGES AFTER DOUBLE JAW ROTATION SURGERY IN SKELETAL CLASS III MALOCCLUSION (골격성 III 급 부정 교합자에서 양악 회전 수술 후 연조직 변화에 대한 연구)

  • Jeong, Mi-Hyang;Choi, Jeong-Ho;Kim, Byuong-Ho;Kim, Seong-Gon;Nahm, Dong-Seok
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.32 no.6
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    • pp.559-565
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    • 2006
  • The aim of this study was to evaluate the amount and interrelationship of the soft and hard tissue changes after simultaneous maxillary clockwise rotation and mandibular setback surgery in skeletal class III malocclusion. The sample comprised of 16 adult patients who had anteroposterior skeletal discrepancy. These patients had received presurgical orthodontic treatment and surgical treatment which consisted of Le fort I Osteotomy and bilateral saggital split ramus osteotomy. The presurgical (T1) and postsurgical (T2) lateral cephalograms were evaluated. The computerized statistical analysis was carried out with SPSS/PC program. The results demonstrated a decrease in the vertical dimension in the soft and hard tissue. The nasolabial angle was increased and the mentolabial angle was decreased. The results showed also many statistically significant correlations(p<0.05). The lower lip closely followed the skeletal movement of the B- point in the horizontal plane. The double jaw rotation surgery can afford a good solution to solve the problems of class III malocclusion cases.