• 제목/요약/키워드: Traction Force

검색결과 231건 처리시간 0.022초

전치부 개교합을 동반한 골관절염 환자에 대한 악간견인장치의 응용 (A Case Report on the Treatment of A TMJ Osteoarthritis Patient with Anterior Open Bite Using An Intermaxillary Traction Device)

  • 류상수;김선희;기우천
    • Journal of Oral Medicine and Pain
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    • 제23권4호
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    • pp.379-385
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    • 1998
  • A patient with TMJ osteoarthritis and anterior open bite was treated with an intermaxillary traction device. Pretreatment examination revelaed a pain in both TMJ during mouth opening, moderate tendernesso f left sternocleidomastoid and right trapezius muscles. Anterior open Bite was aobserved with interincisal distance of 2mm. Tomograms and MRI showed anterior disc displacement withouit reductoin of both temporomandibular joints, and the condyles were flattened and slightly eroded. A pair of full-coverage occlusal appliances was made on both maxillary and mandibular dentition, with pivoting fulcrum on the site of the second moalr. Traction force was gained by the intermaxillary orthodontic elastics which were hooked by orthodontic brackets on the labial surfaces of the upper and lower anterior and premolar teeth. After 8 weeks of traction treatment, the joint pain was subsided completely and the anterior open bite was closed to get an edge to edge relationship of anterior teeth.

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하이브리드 승용차용 전자식 무단변속기의 개발 (Development of Electronically Controlled CVT for Hybrid Passenger Car)

  • 최득환
    • 한국자동차공학회논문집
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    • 제7권9호
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    • pp.75-81
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    • 1999
  • In this paper, the details of electronically controlled CVT is described , which Kia Motor company recently developed in prototype form for hybrid passenger car. This transmission has two input shafts, one for engine and the other for traction motor. The shaft for traction motor is located at rear side which is extended from primary pulley shaft and connected to traction motor through adapter gear box. Adopting two input system, various driving mode is available such as motor alone driving in hybrid vehicle application. As far as electrohydraulic system concerned , this transmission uses two bleed type variable force solenoids for line pressure and ratio control, and one on-off solenoid for clutch control. Another feature for this transmission is that oil pump for transmission is separate from CVT for supplying oil pressure even at vehicle standstill.

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열차추진시스템에서 Switched Reluctance Motor의 속도제어를 위한 제어기 설계 (A Controller Design for Speed Control of the Switched Reluctance Motor in the Train Propulsion System)

  • 김성수;김민석;이종우
    • 전기학회논문지P
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    • 제60권3호
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    • pp.138-143
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    • 2011
  • Electric locomotive is adapted to high speed driving and mass transportation due to obtaining high traction force. The electric locomotive is operated by motor blocks and traction motors. Train speed is controlled by suppling power from motor blocks to traction motors according to reference speed. Speed control of the electric locomotive is efficient by spending energy between motor blocks and traction motors. Currently, switched reluctance motors have been studied because the efficient is higher than induction motors. In this paper, model of the switched reluctance motor is presented and the PID controller is applied to the model for the speed control by using Simulink. Asymmetry converter is used for real-time control and system performance is demonstrated by simulating the speed of switched reluctance motor including PID controller.

Reduction of superior-lateral intact mandibular condyle dislocation with bone traction hook

  • Kim, Bong Chul;Samayoa, Sara Rebeca Kang;Kim, Hyung Jun
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제39권5호
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    • pp.238-241
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    • 2013
  • Lateral and superior-lateral dislocations of the intact condyle are a rare complication, following traumatic insult to the mandible. We report an unusual case of a 54-year-old male patient who experienced both types of dislocations of the intact condyles with symphysis fracture following a road-traffic accident. Under general anesthesia, conventional manipulation was unsuccessful in relocating the condyles into the glenoid fossa. After applying a percutaneous traction force, using a bone traction hook placed at the sigmoid notch, the displaced intact mandibular condyles were repositioned, and the symphyseal fracture was finally reduced and fixed. The mouth opening was within normal limits, and favorable occlusion was confirmed one month postoperatively. To our knowledge, this is the first case of dislocation of both intact condyles--associated with symphysis fracture--being reduced with bone traction hook.

Kopp Ball Variator 무단변속기의 최적설계 (An optimal design of the Kopp Ball Variator continuously variable transmission)

  • 임경호;김두만
    • 오토저널
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    • 제14권1호
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    • pp.38-46
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    • 1992
  • An optimal design technique for minimum power loss in Kopp Ball Variator Continuously Variable Transmission is developed. Kinematic analysis of traction drive contact is performed to find spin for Kopp Ball Variator, and traction force and torque are calculated from mathem atical model of traction drive contact. The objective function for optimal design is total power loss including contact loss and bearing losses. The design contraints are derived from energy balance for input and output power. The formulated optimal design problem is implemented to a non-linear programming algorithm to find minimum power loss. The performance of optimal ly designed Kopp Ball Variator shows that efficiency is increased about 5-10% compare to a commercial unit.

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견인용 IPMSM의 신뢰성 향상을 위한 형상 설계 (Shape Design of IPMSM for the Reliability Improvement of Traction Motors)

  • 이기덕;이주
    • 전기학회논문지
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    • 제64권5호
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    • pp.817-823
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    • 2015
  • IPMSM for traction motor has high power density and wide operating range. But high power density causes internal temperature rise and it makes big armature reaction which causes irreversible demagnetization. And with wide operating range, rotor rotating fast gets stress from centrifugal force. For this reason, traction motor is designed to considerate stress of rotor and irreversible demagnetization for reliability. This paper explains shape design method of 120kW IPMSM accounting improvement of reliability. Finally, the validity of the analysis and the performance evaluation were verified through testing of the final model.

고속전철용 견인유도전동기의 최적화 설계에 관한 연구 (Design Optimization of a Traction Motor for High Speed Trains)

  • 권병일;박승찬;김병택;곽승용;이기호;윤종학;김근웅;이상우
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 1998년도 추계학술대회 논문집
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    • pp.179-186
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    • 1998
  • Three phase squirrel cage induction motor is generally adopted as a traction motor to drive high speed trains because of its robustness for surrounding environment and easy maintenance. In the design of traction molar, reduction of weight is very important in order to reduce kinetic energy to accelerate the vehicle. Therefore, in this paper, design variables of a preliminary designed traction motor to minimize its weight is determined using the optimization technique. Before the optimization process, rotor slot number is determined to reduce vibration and noise by the analysis of magnetic force. As a result, a design example to reduce weight by 12% than that of the preliminary designed motor is presented.

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도시철도 전식방지 조사보고 현황 (Investigation for the Report of DC Traction Stray Current Protection)

  • 이현구;하태현;정호성;한문섭;배정효
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2008년도 추계학술대회 논문집
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    • pp.281-285
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    • 2008
  • Corrosion of metallic structures arises when an electric current flows from the metal into the electrolyte such as soil and water. The potential difference across the metal-electrolyte interface, the driving force for the corrosion current, can emerge due to a variety of temperature, pH, humidity and resistivity etc.. With respect to a given structure, a stray current is to be defined as a current flowing on a structure that is not part of the intended electrical circuit. Stray currents are caused by other cathodic protection installations, grounding systems and welding posts, referred to as steady state stray currents. But most often traction systems like railroads and tramlines are responsible for large dynamic stray currents. This type of stray current is generally results from the leakage of return currents from large DC traction systems that are grounded or have a bad earth-insulated return path. This paper investigates the reports, which is made for protecting the electrical corrosion by the DC traction stray current before the construction period.

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3차원 유한요소법을 이용한 정상상태의 구름접촉해석 (Three-Dimensional Steady-state Rolling Contact Analysis using Finite Element Method)

  • 이동형;서정원;권석진;함영삼
    • 한국정밀공학회지
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    • 제28권5호
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    • pp.565-571
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    • 2011
  • Because most fatigue cracks in wheel and rail take place by rolling contact of wheel and rail in railroad industry, it is critical to understand the rolling contact phenomena, especially for the three-dimensional situation. This paper presents an approach to steady-state rolling contact problem of three-dimensional contact bodies, with or without tangential force, based on the finite element method. The steady-state conditions are controlled by the applied relative slip and tangential force. The three-dimensional distribution of tangential traction and contact stresses on the contact surface are investigated. Results show that the distribution of tangential traction and contact stresses on the contact surface varies rapidly as a result of the variation of stick-slip region. The tangential traction is very close in form to Carter's distribution.

미세아교세포의 진동 거동의 연구 (Oscillatory behavior of microglial cells)

  • 박은영;조영빈;고웅현;박진성;신현정
    • 한국가시화정보학회지
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    • 제19권1호
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    • pp.74-80
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    • 2021
  • Cells regulate their shapes and motility by sensing the cues from the internal and external microenvironment. Under different circumstances, microglia, the brain resident immune cells, undergo dynamic phenotypic changes, one of which is a remarkable periodic oscillatory migration in vitro. However, very little is known about the kinematic and dynamic perspectives of this oscillatory behavior. In this study, we tracked the changes in cell morphology and nuclear displacement, and visualized the forces using traction force microscopy (TFM). By correlation analyses, we confirmed that the lamellipodia formation preceded the nuclear translocation. Moreover, traction, developed following lamellipodia formation, was found to be localized and fluctuated at two ends of the oscillating cells. Taken together, our results imply that oscillatory microglial cells feature a viscoelastic migration, which will contribute to the field of cell mechanics.