• Title/Summary/Keyword: Dislocation

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Evaluation of Internal Stress and Dislocation Velocity in Creep with 25Cr-20Ni Stainless Steels (25Cr-20Ni계 스테인리스강의 크리프 변형중 내부응력과 운동전위밀도의 평가)

  • Park, In-Duck;Ahn, Seok-Hwan;Nam, Ki-Woo
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.296-301
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    • 2004
  • By the purpose to investigate the change of internal stress and mobile dislocation density in creep, the stress relaxation test is carried out in the condition of each strain. Mobile dislocation density increased until it reached minimum creep rate and after that, it decreased and internal stress didn't have the change approximately until it reached minimum creep rate and after that, it decreased. The stress relaxation rate is fast and approached zero after 1.5 seconds after the beginning of the stress relaxation. And the larger the applied stress is, the larger the internal stress is. By the evaluation of mobility of dislocation, the dislocations glide viscously in STS31OJlTB but it is the dislocations glide viscously which N passes by cutting Cr atom rather than typical viscosity movement after calculating mobility of dislocation.

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Effect of open-core screw dislocation on axial conductivity in semiconductor crystals

  • Taira, Hisao;Sato, Motohiro
    • Advances in nano research
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    • v.1 no.3
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    • pp.171-182
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    • 2013
  • The alternating current (AC) conductivity in semiconductor crystals with an open-core screw dislocation is studied in the current work. The screw dislocation in crystalline media results in an effective potential field which affects the electronic transport properties of the system. Therefore, from a technological view point, it is interesting to investigate properties of AC conductivity at frequencies of a few terahertz. To quantify the screw-induced potential effect, we calculated the AC conductivity of dislocated crystals using the Kubo formula. The conductivity showed peaks within the terahertz frequency region, where the amplitude of the AC conductivity was large enough to be measured in experiments. The measurable conductivity peaks did not arise in dislocation-free crystals threaded by a magnetic flux tube. These results imply different conductivity mechanisms in crystals with a screw dislocation than those threaded by a magnetic flux tube, despite the apparent similarity in their electronic eigenstates.

Operative Treatment for Bilateral Chronic Recurrent Dislocation of the Peroneal Tendon: A Case Report (양측 족관절에 발생한 만성 재발성 비골건 탈구의 수술적 치료: 증례 보고)

  • Na, Hwa-Yeop;Song, Woo-Suk;Lee, Joo-Young
    • Journal of Korean Foot and Ankle Society
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    • v.24 no.4
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    • pp.161-164
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    • 2020
  • A peroneal dislocation is a rare disease that is often misdiagnosed as a simple sprain and can be treated inadequately in the acute phase. For this reason, it is important to have an appropriate diagnosis in the early stages because it can progress to chronic and recurrent conditions. Surgical treatment is considered mainly when progressing to chronic recurrent dislocation. Recently, patients with an acute peroneal dislocation tend to prefer surgical treatment, so accurate initial diagnosis and management are very important. This paper reports a case of chronic recurrent peroneal tendon dislocation in both ankle joints, which was treated by a superior peroneal retinaculum reconstruction and a groove deepening procedure.

Conservative management of dislocated temporomandibular joints: A case report (턱관절 탈구의 보존적 치료법에 대한 증례보고)

  • Park, Jo-Eun;Kim, Hye-Kyoung;Choi, Hee-Hoon;Kim, Mee-Eun
    • Journal of Oral Medicine and Pain
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    • v.38 no.4
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    • pp.319-324
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    • 2013
  • Dislocation of the temporomandibular joint (TMJ) occurs when the mandibular condylar head is displaced completely out of the glenoid fossa and cannot be reduced by the patient. The occurrence of bilateral anterior dislocation is the most common. Dislocations can be classified into three types in terms of duration and frequency of dislocation, i.e., acute, chronic and recurrent. There are various treatment modalities for dislocation from conservative try to surgical intervention. The selection for the appropriate modality mainly depends on the types of dislocation as previously stated. The authors report three cases of dislocation with different treatment modalities according to the duration of dislocation. In particular, we tried prosthetic approach instead of surgical intervention in the patient with chronic dislocation.

A Novel Treatment of Recurrent Temporomandibular Joint Dislocation with Intermaxillary Fixation Using Microimplant: A Case Report

  • Kee, In-Kyung;Byun, Jin-Seok;Choi, Jae-Kap
    • Journal of Oral Medicine and Pain
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    • v.39 no.4
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    • pp.156-162
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    • 2014
  • Dislocation of temporomandibular joint (TMJ) is troublesome condition which was most commonly shown far anteriorly displaced mandibular condyle to the articular eminence, thereby make it impossible to close one's mouth. It is often referred to as 'open lock' in clinically. Although anatomical modification of the articular eminence through eminectomy has been considered most satisfactory and efffective treatment for managing the recurrent dislocation, it seldom performs clinically due to its invasiveness and patient's reluctance. We thought a shortterm intermaxillary fixation could be of benefit to the patient suffering from recurrent dislocation. A 21-year-old male patient with recurrent TMJ dislocation which had developed after excessive mouth opening, was successfully treated with intermaxillay fixation using microimplant for 2 months. It is more conservative and less complicated method than eminectomy in treating recurrent TMJ dislocation. Transient intermaxillary fixation using microimplant and elastics could be one of treatment options for recurrent TMJ dislocation.

The Effectiveness of Occlusal Splint for the Treatment of Temporomandibular Joint Dislocation

  • Lim, Hyun-Dae;Lee, You-Mee;Kang, Jin-Kyu
    • Journal of Oral Medicine and Pain
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    • v.39 no.4
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    • pp.152-155
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    • 2014
  • Temporomandibular joint (TMJ) dislocation is defined that the disc-condyle complex is positioned anterior to the articular eminence in the open mouth position, and is unable to return to a normal closed mouth position without a manipulative maneuver. TMJ dislocation can recur habitually and result several problems to patients such as discomfort, pain, fear, and anxiety. The only definitive treatment for TMJ dislocation is surgical alteration of the joint itself. In most cases, however, a surgical procedure is far too aggressive for the symptoms experienced by the patient. In addition, the effect of surgical treatment may be insufficient, and the recurrence have been reported. It is also possible to develop several complications after surgical treatment. Therefore much effort should be directed at supportive therapy in an attempt to eliminate the disorder or at least reduce the symptom to tolerable levels. Through this cases the authors present favorable treatment outcome using occlusal splint with the patient of TMJ dislocation. Occlusal splint therapy can be considered as easy, safe, and useful non-invasive modality to treatment of TMJ dislocation.

Manual Reduction of Temporomandibular Joint Long-standing Dislocation under General Anesthesia (전신마취하에 도수정복된 측두하악관절 장기탈구)

  • Son, Jeong-Seog;Oh, Ji-Hyeon;Choi, Byung-Ho;Yoo, Jae-Ha
    • Journal of The Korean Dental Society of Anesthesiology
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    • v.13 no.3
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    • pp.121-126
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    • 2013
  • Temporomandibular joint (TMJ) dislocation is an acute paintful condition that causes severe functional limitation. So, manual reduction is the treatment of choice and should be performed as early as possible. Long-term dislocation of the TMJ that has persisted for more than 1 month is comparatively rare. This may include severe illness, neurological diseases and prolonged intensive care hospitalization with oral intubation and sedation. A joint that remains prolonged dislocated undergoes morphological change which is also true for periarticular tissue, especially in ligaments and muscles. Treatment of long-term TMJ dislocation should be different from acute TMJ dislocation, as simple reduction is difficult to achieve and it's likely to redislocate. The prevention of redislocation after reduction should be considered. This is a case report of about manual reduction of temporomandibular joint long-standing dislocation under general anesthesia.

Total Hip Replacement for Treatment of Chronic Coxofemoral Joint Dislocation in 7 Dogs

  • Yoon, Jang-Won;Heo, Su-Young;Jeong, Seong-Mok;Lee, Hae-Beom
    • Journal of Veterinary Clinics
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    • v.36 no.4
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    • pp.229-232
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    • 2019
  • Total Hip Replacement in a patient with chronic coxofemoral joint dislocation is a challenging problem because chronic coxofemoral joint dislocation causes severe morphological changes. These challenging factors make surgery more difficult and increase the possibility of postoperative complications including cup implant dislocation and prosthetic joint luxation. All patients were diagnosed having at least 2 months of coxofemoral joint dislocation. On physical examination, crepitus was noted in the coxofemoral joint. Radiographs revealed hip joint dislocation with mild to severe degenerative changes. Total hip replacement was planned for all patients. Dorsal acetabular rim deficiency in 3 cases was augmented using a locking plate and polymethylmethacrylate bone cement. All cases have shown difficulty in prosthetic joint reduction. Pectineus and rectus femoris muscle origin were released in all cases. At 12 months follow up, all patients showed satisfactory ambulation. The issues on perioperative prosthetic joint reduction and luxation due to chronic coxofemoral joint luxation with muscle contracture and dorsal acetabular rim deficiency can be resolved by muscle releasing and dorsal acetabular rim augmentation.

Initial and Recurrent Anterior Dislocation in Shoulder (견관절 초기 전방 탈구와 재발성 전방 탈구)

  • Kim Young-Kyu;Lee Jae-Hoon;Kim Hyun-Min;Lee Choong-Hoon
    • Clinics in Shoulder and Elbow
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    • v.8 no.2
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    • pp.148-153
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    • 2005
  • Purpose: To assess the usefulness of early stabilization for initial shoulder dislocation which is indicated in some patients by comparing the arthroscopic findings and the outcomes of Bankart repair in the initial and recurrent dislocation. Materials and Methods: The study was performed on 16 cases of initial dislocation and 44 cases of recurrent dislocation. The follow-up period was 25 months in the initial dislocation group and 28 months in the recurrent group. Bankart lesion and the adjacent tissues were compared, and the results were evaluated by the Rowe rating scale. Results: Detached labrum and capsular ligament of the initial dislocation group were elastic and unretracted. While in the recurrent dislocation those were inelastic, and displaced and adhesive in many cases. The outcomes were mean 95 points in the initial group and 91 points in the recurrent group. In the initial group, apprehension was detected in only 1 case(6%). In the recurrent group, instability was detected in 4 cases(9%). Conclusion: Our data suggest that Bankart lesion in the initial dislocation can be repaired readily by surgery, the recovery is efficient, and the recurrence would be reduced. Thus, in active young sports lovers as well as athletes, early stabilization surgery for initial shoulder dislocation may be more helpful.

Defect Structures in LiNbO3 Single Crystals Grown by Czochralski Method : Dislocation Etch Pits Morphology (Czochralski법으로 성장시킨 LiNbO3 단결정의 결함구조 : Dislocation Etch Pits Morphology)

  • 장동석;오근호
    • Journal of the Korean Ceramic Society
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    • v.26 no.5
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    • pp.661-669
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    • 1989
  • The defect structure in LiNbO3 single crystals grown by Czochralski method from the congruently melting composition were investigated. Chemical etching patterns were studied in x-plane, z-plane, and major cleavage plane, respectively, dislocation density was higher at the periphery of crystals than at the center because the thermal stress due to radial temperature gradient had a main effect on it, as compared with dislocations formed from the solid-liquid interface. Many dislocation lineages were arranged along several directions.

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