• 제목/요약/키워드: proximal

검색결과 2,600건 처리시간 0.026초

A NEW PROJECTION ALGORITHM FOR SOLVING A SYSTEM OF NONLINEAR EQUATIONS WITH CONVEX CONSTRAINTS

  • Zheng, Lian
    • 대한수학회보
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    • 제50권3호
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    • pp.823-832
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    • 2013
  • We present a new algorithm for solving a system of nonlinear equations with convex constraints which combines proximal point and projection methodologies. Compared with the existing projection methods for solving the problem, we use a different system of linear equations to obtain the proximal point; and moreover, at the step of getting next iterate, our projection way and projection region are also different. Based on the Armijo-type line search procedure, a new hyperplane is introduced. Using the separate property of hyperplane, the new algorithm is proved to be globally convergent under much weaker assumptions than monotone or more generally pseudomonotone. We study the convergence rate of the iterative sequence under very mild error bound conditions.

Bilateral Vertebral Artery Dissecting Aneurysms : A Long Term Follow-up Results of Microsurgical Trapping and Proximal Occlusion

  • Kim, Young-June;Lee, Sang-Youl;Rhee, Woo-Tack;Jang, Yeon-Gyu
    • Journal of Korean Neurosurgical Society
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    • 제41권5호
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    • pp.318-322
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    • 2007
  • Regarding the bilateral vertebral artery [VA] dissecting aneurysms, treatment strategy remains controversial because there have not been enough cases to reach a conclusion on the best treatment. We present a patient underwent staged microsurgical trapping and endovascular coiling for each dissecting aneurysm of bilateral VA presenting subarachnoid hemorrhage [SAH]. The ruptured side was managed by VA trapping procedure without any neurological deficit. Postoperative cerebral angiography revealed patent right PICA without filling of previous right dissecting aneurysm and spontaneous occlusion of the left dissecting aneurysm one month after trapping procedure. However, follow-up angiography revealed recanalization and growing of the left VA dissecting aneurysm one year after the operation. The patient underwent endovascular embolization using GDC for the proximal occlusion of the left VA and postoperative course was uneventful.

환자의 손가락 특성을 모사하는 로봇 개발 (Development of Finger Robot for Simulating Fingers with Contracture and Spasticity)

  • 하도경;송민;박형순
    • 재활복지공학회논문지
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    • 제8권4호
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    • pp.233-238
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    • 2014
  • 본 논문에서는 손재활기기를 평가하고 신뢰도 높은 검진을 위해 검진자의 훈련용으로 사용할 수 있는 손가락 모사 로봇을 개발하였다. 먼저 실제 사람의 손가락 크기를 고려하여 손허리가락 관절(Metacarpophalangeal)과 첫마디뼈 관절 (Proximal Interphalangeal)을 구동할 수 있는 메커니즘을 설계하였고 이를 통해 뇌졸중과 같은 신경 손상 환자들에게서 나타나는 경직(spasticity)과 구축(contracture)현상을 모사하는 알고리즘을 구현하여 경직과 구축의 정도를 조절하여 다양한 환자들의 특징을 구현할 수 있도록 하였다.

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가와사키병에 의한 관상동맥류의 관상동맥우회로술 -치험 1례- (CABG in Coronary Aneurysm Due to Kawasaki Disease)

  • 김종욱;이재원;송명근
    • Journal of Chest Surgery
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    • 제28권4호
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    • pp.398-400
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    • 1995
  • Kawasaki s disease is a multisystemic disorder that is an important cause of cardiovascular disease in children. We experienced a case of coronary artery aneurysm secondary to Kawasaki s disease. The patient was 12-year-old female presented as exertional dyspnea & chest pain[NYHA classII . Her coronary angiogram showed saccular aneurysms at proximal right coronary artery and proximal left anterior descending artery. CABG was performed by use of double internal mammary artery.Postoperative E.K.G. showed a normal pattern.She discharged at postoperative 10th day without problem. 4 months after discharge, she had no dyspnea & chest pain in exertion[NYHA class I .

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상행 대동맥과 하행 흉부 대동맥에 동시에 발생한 가성 대동맥류 치험 1례 (Pseudoaneurysm Involving Proximal Ascending Aorta and Proximal Descending Thoracic Aorta)

  • 이호철;류한영
    • Journal of Chest Surgery
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    • 제29권3호
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    • pp.337-341
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    • 1996
  • A 40-year-old male patient who had ascending aortic pseudoaneurysm Involving right coronary artery obstruction and thoracic descending aortic pseudoaneurysm was successfully managed by two-stage operation. Repair of intimal tear of ascending aortic pseudoaneurysm with a patch of woven dacron vascular graft and right coronary artery bypass graft with great saphenous vein were performed in first stage operation. On 28 days postoperatively, Repair of intimal tear of descending aortic pseudoaneurysm with a patch of woven dacron vascular graft was done under the femorofemoral partial cardiopulri!onary bypass in second stage operation. The patient was discharged at postoperative 13th days without any evident.

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유한요소법을 이용한 인공고관절 주대형태의 개선에 대한 연구 (A Study for Improvement of the Femoral Stem Type using the Finite Element Analysis)

  • 윤경렬;원예연;이수훈
    • 한국CDE학회논문집
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    • 제5권2호
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    • pp.122-126
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    • 2000
  • A major mechanical problem with total hip replacement is the loosening of the femoral component. The loss of proximal support, with firm fixation distally, has been thought to be a major caused of fatigue failure of femoral stems. While many causes have been proposed, the most frequently suggested cause of the calcar resorption is the disuse atrophy of the cortex of the calcar due to the stress shielding of the proximal bone by the metal femoral stem. In this research, the new-designed stem(modified collar stem) was considered which made a hole inside stem and had a 3 mm thickness. Using the 3-dimensional finite element methods, the common collar stem and the modified colla stem was modeled and analysed. Also, the two models was compared. The results showed that the modified collar stem decreased the stress-shielding and it made a effective load transfer at the entire femoral region.

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A Schwannoma Originating from Median Nerve at Proximal Forearm Caused Ulnar Nerve Symptom by Compression

  • Yoo, Jeong Hyun;Kim, Joon Yub;Kim, Hyoung Soo;Kim, Joo Hak;Sung, Ki Hyuk;Song, Sang Hun;Kwak, Ho Il
    • Archives of Reconstructive Microsurgery
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    • 제23권2호
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    • pp.86-88
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    • 2014
  • A schwannoma is a benign soft tissue tumor arising from the nerve sheath of a Schwann cell. Clinically, a schwannoma is an asymptomatic mass rarely causing neurologic deficits. However, it can cause discomfort as well as motor and sensory disturbances by compressing the nerve of its origin. The authors encountered a huge schwannoma arising from the median nerve at the proximal forearm, which caused symptoms mainly in the ulnar nerve. The tingling sensation along the ulnar nerve disappeared completely after enucleation of the schwannoma originating from the median nerve.

도구 및 성인과의 상호작용이 유아의 인지수준에 미치는 효과 (The Effects of Interaction with an Object and with an Adult on Young Children's Cognitive Level)

  • 이소은;송지영
    • 아동학회지
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    • 제23권1호
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    • pp.71-85
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    • 2002
  • This study examined the effects of different interaction styles, that is, interaction with an object and interaction with an adult, on young children's cognitive level. Subjects were 150 5-year-old children. The task required children to predict the working of a mathematical balance beam. Seven cognitive levels were identified based on the logic of prediction. Data were analyzed by t-test, F-test, Duncan Test and Wilcoxon Matched-Pairs Test. Results showed that both interaction styles caused improvement in children's cognitive level, but when interaction with an adult was divided into two categories, i.e., interaction with the higher group and interaction with the lower group, the latter experienced decline in cognitive level. Regardless of sex, interactions within the Zone of Proximal Development and with the object were found to be effective methods for children's cognitive improvement.

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A case report of Madelung's disease

  • Jang, Nam;Shin, Hyun Woo;Kim, Junekyu;Yoon, Kun Chul
    • 대한두개안면성형외과학회지
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    • 제21권5호
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    • pp.305-308
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    • 2020
  • Madelung's disease (MD) otherwise known as Launois-Bensaude syndrome, multiple symmetrical lipomatosis, or benign symmetric lipomatosis, is a rare disease characterized by abnormal diffuse lipomatosis in proximal upper limbs and neck. Here, we report a rare case of MD. A 66-year-old man presented with massive growth of soft tissues in the cervico-occipital region of more than 2 years duration. Physical examination showed diffuse enlargement of the anterior neck (Madelung's collar) and three huge humps at the posterior neck. Under a diagnosis of MD, lipectomy via a single anterior transverse incision and liposuction were performed. This rare case report may be helpful for assessing patients with abnormal diffuse lipomatosis in the neck and proximal upper limbs.

Pulmonary Toxicity of Single Walled Carbon Nanotubes

  • Castranova Vincent
    • 한국환경성돌연변이발암원학회:학술대회논문집
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    • 한국환경성돌연변이발암원학회 2005년도 춘계 국제심포지엄 및 학술대회
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    • pp.91-96
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    • 2005
  • A. Nebulized SWCNT dispersed as aggregates and nanotubes B. Aspiration causes transient oxidant stress, damage and inflammation, peaking by 7 days post-exposure C. Histology visualizes aggregates in the tirminal bronchials and proximal alveli with no visible material in distal alve oli D. Size of aggregates doesn't change with time E. Rapid fibrosis - begins in 7 days and progresses through 60 day post-exposure 1) Fibrosis in granulomatous lesions containing aggregates 2) Diffuse interstitial fibrosis in distal alveolar walls with no visible SWCNT F. Used silver enhancement of gold-labeled SWCNT 1) See aggregates in proximal alveoli and terminal bronchials 2) See nanoropes in walls of distal alveoli

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