• Title/Summary/Keyword: disc

Search Result 3,912, Processing Time 0.038 seconds

CHANGE OF JOINT SPACE ACCORDING TO SIDEWAYS DISC DISPLACEMENT OF TMJ (악관절원판의 측방변위에 따른 관절간극의 변화)

  • Kim, Joon-Bae;Lee, Doo-Hee;Kim, Hyung-Soo;Oh, Soon-Ho
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • v.27 no.4
    • /
    • pp.337-343
    • /
    • 2001
  • Objective. Disc displacement may affect the joint space narrowing between condyle head and glenoid fossa. This study was designed to evaluate the correlation between the joint space change and the directions of disc displacement. Study Design. Two hundreds temporomandibular joints MR images of TMD patients (170 joints) and asymptomatic volunteers (30 joints) were evaluated for this purpose. Anterior disc displacement was divided into 3 stages (normal, little to mild, and moderate to severe displacement) based on sagittal images. And sideways displacement was classified as 3 categories (center, medial and lateral displacement) based on coronal images, then joint spaces were measured at medial, central and lateral parts of condyle head on coronal MR images, respectively. The joint spaces of 7 groups divided according to the severity and the direction of disc displacement were compared. Results. The reduction of the joint space was affected by sideways disc displacement at the opposite side of the condyle head, except the cases accompanied with severe anteriorly and laterally displaced disc. Conclusion. The sideways disc displacement affected on the opposite side temporomandibular joint space width.

  • PDF

A Study on the Torque Characteristics of Butterfly Valve Disc in Fire Protection (소화용 버터플라이 밸브 디스크의 토크특성에 관한 연구)

  • 이동명;박승옥
    • Fire Science and Engineering
    • /
    • v.16 no.2
    • /
    • pp.33-37
    • /
    • 2002
  • This study has investigated hydrodynamic of torque characteristics for disc of butterfly valve that is used in control for fire-protection water, The free-streamline theory is applied to predict hydrodynamic of torque characteristics. The torque characteristics of disc are corrected for the angles of attack of valve disc and surrounding velocity of flow by theoretical torque equation, and correction equation is added. The torque characteristics of disc are investigated for the ratio of hub thickness to the valve diameter. The result of prediction are shown to be successful as that show typical torque characteristics of butterfly valve. Since the velocity distribution around the disc is confirmed in a visualization, it is confirmed that the free-streamline theory can be used to predict the torque characteristics of disc.

Clinical Observation of Improvement Made by Bee Venom Therapy at Cervical Hyeopcheokhyeol on Case of Upper Limb Disability Caused by Cervical Disc Herniations (경추 협척혈 봉약침 치료에 호전을 보인 상지 활동장애를 호소하는 경추 추간판 탈출증 환자 1례)

  • Shin, Hwa-Young;Kim, Jae-Su;Lee, Kyung-Min
    • Korean Journal of Oriental Medicine
    • /
    • v.16 no.2
    • /
    • pp.119-124
    • /
    • 2010
  • Cervical disc herniations can press on the spinal cord and cause a problem called cervical myelopathy. The most common symptom of cervical disc herniation is neck pain that spreads down to the upper limb in various locations. There can also be associated with weakness and movement disorders of upper limb. In Oriental medicine, cervical disc herniation is treated with herb-med, physical therapy, acupuncture, Chuna, etc, but the Bee Venom therapy is the most common and effective. In this case, we used the Bee Venom therapy at cervical hyeopcheokhyeol for about 2 months to a patient who was diagnosed with disc herniation at Cervical 5-6, 6-7 and appealed weakness, limited elevation and abduction of the left upper limb. As a result, left upper limb disability was improved. Using the Bee Venom therapy at cervical hyeopcheokhyeol that are effective on movement disorders and neurological diseases of upper limb is an effective treatment to upper limb disability diagnosed with cervical disc herniation, and suggests the direction of the treatment to upper limb weakness and movement disorders diagnosed with cervical disc herniation.

A Study on Braking Performance of Break Disc (브레이크 디스크의 제동 성능에 관한 연구)

  • Ryu, Mi-Ra;Bae, Hui-Eun;Kim, Hyun-Su;Lee, Dae-Hee;Lee, Seong-Beom;Park, Jeong-Ho
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.12 no.3
    • /
    • pp.13-20
    • /
    • 2013
  • The present research aims to develop the aluminum disc brake replacing the existing cast iron disc brake. Material such as aluminum using FEM numerical analysis in order to improve the characteristics of each element, we analyze the performance characteristics and braking time you try to change. We try to lay the foundation for the development of an aluminum disc by investigating performance characteristics of the existing cast iron disc brake and comparing them with those of the aluminum disc. This involves FEM dynamics analysis for disc materials and experimental tests using the brake dynamometer. From this study, the results of 7075 aluminum braking performance can be seen that the best.

A Study on the Cross-drilling Effects of Brake Disc Rotor (브레이크 디스크 로터 표면 수직 구멍의 영향에 관한 연구)

  • Seo, Young-Jin;Oh, Je-Ha;Lee, Jun-Sang;Kang, Kyoung-Soo;Jung, Geun-Sung
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.16 no.1
    • /
    • pp.100-105
    • /
    • 2008
  • Cross-drilling on the brake disc is generally known as a way of improving cooling efficiency. In other theories, cross-drilled holes act like a path of gas or water and are also known that they can reduce fading and wetting of brake rotors. However, in disc rotors with cross-drilling, thermal crack phenomena have been reported more frequently and more manufacturing cost should be paid than non cross-drilled disc rotors. In this study, to examine various effects of cross-drilling on the brake disc, two kinds of brake disc rotors, cross-drilled and non cross-drilled, were used in computational fluid dynamic analyses and dynamometer tests.

Ultrasound-Guided Posterolateral Approach for Midline Calcified Thoracic Disc Herniation

  • Tan, Lee A.;Lopes, Demetrius K.;Fontes, Ricardo B.V.
    • Journal of Korean Neurosurgical Society
    • /
    • v.55 no.6
    • /
    • pp.383-386
    • /
    • 2014
  • Objective : Symptomatic thoracic disc herniation often requires prompt surgical treatment to prevent neurological deterioration and permanent deficits. Anterior approaches offer direct visualization and access to the herniated disc and anterior dura but require access surgeons and are often associated with considerable postoperative pain and pulmonary complications. A disadvantage with using posterior approaches in the setting of central calcified thoracic disc herniation however, has been the limited visualization of anterior dura and difficulty to accurately assess the extent of decompression. Methods : We report our experience with intraoperative ultrasound (US) guidance during a modified posterior transpedicular approach for removal of a central calcified thoracic disc herniation with a review of pertinent literature. Results : The herniated thoracic disc was successfully removed with posterior approach with the aid of intraoperative US. The patient had significant neurological improvement at three months follow-up. Conclusion : Intraoperative ultrasound is a simple yet valuable tool for real-time imaging during transpedicular thoracic discectomy. Visualization provided by intraoperative US increases the safety profile of posterior approaches and may make thoracotomy unnecessary in a selected group of patients, especially when a patient has existing pulmonary disease or is otherwise not medically fit for the transthoracic approach.

A Study on Temperature Field and Contact Pressure in Ventilated Disc-Pad Brake by 3D Thermo-mechanical Coupling Model (3차원 열-기계 커플링 모델에 의한 벤틸레이티드 디스크-패드 브레이크의 온도 분포와 접촉 압력에 관한 연구)

  • Hwang, Pyung;Seo, Hee-Chang;Wu, Xuan
    • Tribology and Lubricants
    • /
    • v.25 no.6
    • /
    • pp.421-426
    • /
    • 2009
  • The brake system is important part of automobile safety system. The disc brake system is divided two parts: the rotating axisymmetrical disc and the stationary pads. During braking, the kinetic energy and potential energy of moving vehicle were converted into the thermal energy through frictional heat between the brake disc and the pads. The frictional heat, which is generated on the interface of the disc and pads, can cause high temperature during the braking process. The object of present work is to determine temperature and thermal stress, to compare to simulation results and experimental results in the disc by partial 3D model of ventilated disc brake with appropriate boundary conditions. In the simulation process, the mechanical loads were applied to the thermo-mechanical coupling analysis in order to simulate the process of heat produced by friction.

CHANCE OF JOINT SPACE ACCORDING TO ANTERIOR DISC DISPLACEMENT OF TMJ (악관절원판의 전방변위에 따른 관절간극의 변화)

  • Bae Jung-Soo;Kim Joon-Bae;Kim Hyung-Soon
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.39 no.4
    • /
    • pp.410-416
    • /
    • 2001
  • Objective: Disc displacement may affect the joint space narrowing between condylar head and glenoid fossa. This study was designed to evaluate the correlation between the joint space change and the severity of anterior disc displacement. Materials and Methods: Two hundreds temporomandibular joints MR images of TMD patients(170 joints) and asymptomatic volunteers(30 joints) were evaluated for this purpose. Anterior disc displacement was divided into 3 stages(normal, little to mild, and moderate to severe displacement) based on sagittal images, then joint spaces were measured at medial, central and lateral parts of condyle head on coronal MR images, respectively The joint spaces of 3 groups divided according to the severity of anterior disc displacement were compared. Results: The reduction of joint space was related to the severity of the anterior disc displacement at lateral, medial side and especially at center Conclusion: The temporomandibular joint space was affected by the severity of the anterior disc displacement.

  • PDF

Intradural Lumbar Disc Rupture - Case Report - (경막내 요추 추간반 탈출증 - 증례보고 -)

  • Jeong, Ju-Ho;Lee, Sang-Gu;Yoo, Chan-Jong;Han, Ki-Soo;Kim, Woo-Kyung;Kim, Young-Bo;Park, Cheol-Wan;Lee, Uhn
    • Journal of Korean Neurosurgical Society
    • /
    • v.30 no.10
    • /
    • pp.1233-1236
    • /
    • 2001
  • The intradural lumbar disc herniation which was first described by Dandy in 1942 is unusual. The pathogenesis is obscure and preoperative diagnosis is not easy. The patient usually have more severe neurologic deficits than those found in the much more common extradural disc herniations. We experienced two cases of the intradural lumbar disc herniation who had previous disc operations and the symptoms and neurologic signs were improved after removal of the intradural sequestration of disc fragments.

  • PDF

A Study of Estimation of Lumbar Intervertebral Disc Size by Colombini's Method (Colombini 방법에 의한 요추부 추간판 크기 추정에 관한 연구)

  • Kim, Jong-Soon
    • The Journal of Korean Physical Therapy
    • /
    • v.19 no.1
    • /
    • pp.23-31
    • /
    • 2007
  • Purpose: As a preliminary study, the purpose of this study was to examine the indirect estimation of the lumbar intervertebral disc size by two anthropometric methods, in order to compare these indirect methods with the direct analysis by radiological imaging. Methods: The wrist, elbow, knee, and ankle joint (both right and left) diameters were measured in 52 volunteers, and then intervertebral disc size was calculated using two anthropometric methods (Colombini and modified Colombini). The data were analysed with independent t-test to assess clinical usefulness. Results: When using right and left joint diameter, there was no significant difference in the estimation value of the L4-5 and L5-S1 intervetebral disc sizes. However, the study has shown that male subjects have significantly larger L4-5 and L5-S1 intervertebral disc sizes, compared with those of female subjects. In addition, disc sizes calculated by Colombini's formula were significantly larger than modified Colombini's formula. Conclusion: The indirect estimation of the intervertebral disc size by anthropometric method can be considered as a clinically useful method. However, further study should be conducted to compare anthropometric values with other radiological imaging.

  • PDF