• Journal of Advanced Marine Engineering and Technology
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• 제32권8호
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• pp.1149-1156
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• 2008

The principle of self clamping friction clutch is presented in this paper and the transmitted torque capacity is also calculated. In order to enlarge the friction force, a part of rotating force of driving side is converted to normal force of friction materials by clamping arm. The increased normal force of friction materials assures the large friction force and the transmitted torque capacity of clutch becomes large. The self clamping friction clutch is adopted in the tube type air pressure clutch and the condition of stability is investigated. It is proven that the inclined angle of clamping arm and the friction factor of friction materials are the essential elements in stability and torque capacity of self clamping friction clutch. The transmitted torque capacity of self clamping friction clutch is compared with air pressure clutch. The normal force of friction lining is magnified by 1/(1-k) and the transmitted torque capacity is also magnified with same proportion comparing with air pressure clutch. The larger the friction factor of friction lining, the larger the magnification factor. The longer the clamping arm, the smaller the magnification factor. It must be also noted that the value of k=${\mu}Y/X$ is the criterion of stability. If the value of k=${\mu}Y/X$ is greater than or equal to 1, the self clamping friction clutch is unstable and it can not be used as clutch.

• Journal of Trauma and Injury
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• 제26권3호
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• pp.243-247
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• 2013

Introduction: Surgical treatment of subclavian artery (SA) injury is challenging because approaching the lesion directly and clamping the proximal artery is difficult. This can be overcome by using an endovascular technique. Case 1: A 37-year-old male was drawn into the concrete mixer truck. He had a right SA injury with multiple traumatic injuries: an open fracture of the right leg with posterior tibial artery (PTA) injury, a right hemothorax, and fractures of the clavicle, scapula, ribs, cervical spine and nasal bone. The injury severity score (ISS) was 27. Computed tomography (CT) showed a 30-mm-length thrombotic occlusion in the right SA, which was 15 mm distal to the vertebral artery (VA). A self-expandable stent($8mm{\times}40mm$ in size) was deployed through the right femoral artery while preserving VA flow, and the radial pulse was palpable after deployment. Other operations were performed sequentially. He had a viable right arm during a 13-month follow-up period. Case 2: A 25-year-old male was admitted to our hospital due to a motorcycle accident. The ISS was 34 because of a hemothorax and open fractures of the mandible and the left hand. Intraoperative angiography was done through a right femoral artery puncture. Contrast extravasation of the SA was detected just outside the left rib cage. After balloon catheter had been inflated just proximal to the bleeding site, direct surgical exploration was performed through infraclavicular skin incision. The transected SA was identified, and an interposition graft was performed using a saphenous vein graft. Other operations were performed sequentially. He had a viable left arm during a 15-month follow-up period. Conclusion: The challenge of repairing an SA injury can be overcome by using an endovascular approach.

• Journal of Chest Surgery
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• 제29권3호
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• pp.346-349
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• 1996

This 32 year old female patient underwent left radical mastectomy due to ductal carcinoma on May 1990, and treated with FAM (5-fluorouracil, Adriamycin and Mitomycin C) regimen postoperatively. However, right cervical Iymph node enlargement and facial edema progressively developed since December 199). On April 1994, operation was performed, and findings were as followes; x4$\times$5$\times$7 to 1 : 1 $\times$ 1 cm sized multiple enlarged and hyperemic Iymph nodes were scatterred throughout submandibular area to the junction of superior vents cave and pericardium, and partially invaded both anterior segmental lobe, sternum and both distal tip of clavicles. After radical dissection of the nodes of neck and mediastinal nodes, and wedge resection of both anterior segments of lung, and partial resection of both clavicle tips and total sternum. The both innominate veins and superior vena cava were partially obstructed by invaded cancer SVC reconstruction was done with preclotted 10$\times$ 10$\times$ 18mm Y shap d woven Dacron graft, which was anastomosed to the point of the junction of subclavian vein and jugular vein after cross clamping both veins and 2cm above the pericardial junction with one arm clamp. After maintaining blood drainage to the SVC from the right side, left innominate vein was anastomosed with 4-0 Prolene continuous running suture. Bone cement was used for resected sternal portion and clavicular ends were fixed to postal portion with 18 Gauge wires. The patient was treated with radiation and chemotherapy after discharge, and there were no evidence of regrowing of the mass nor obstruction of the graft inspite of no antithrombotic therapy.

• Journal of Chest Surgery
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• 제33권8호
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• pp.623-629
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• 2000

Background: There has been controversy over the prevalence of recoarctation in infants treated by subclavian flap aortoplasty(SFA) for coarctation of the aorta. To assess the rate of recurrence of coarctation after SFA, we reviewed the surgical results of SFA in infants with coarctation of the aorta. Material and method: Between 1986 and 1998, a total of 25 patients less than 1 year of age(12 neonates and 13 infants) underwent SFA for aortic coarctation. Age at operation was 3.0$\pm$3.0 months(mean $\pm$ standard deviation); mean weight was 5.0$\pm$1.4kg. Classic SFA was performed in 20 patients, reversed SFA in 2 patients, subclavian artery reimplantation in 2 patients and the combined resection-flap aortoplasty in one. Result: The aortic clamping time ranged from 20 to 88 minutes(mean 35.8 minutes). There were one operative death and two late deaths. There was no case of paraplegia or left arm ischemia in complications. Twenty-one(84%) of 24 hospital survivors were followed for 26.0$\pm$24.0 months. The risk of recoarctation in neonates(33.3%) was a little greater than infants(25.0%) without statistical significance. Conclusion: This study revealed that SFA resulted a relatively high incidence of recarctation in infants. It is desirable to select other methods of surgical treatment(combined resection-flap aortoplasty, extended end-to-end repair etc.) for severe isthmic coarctation or hypoplasia of the distal aortic arch in infants, instead of choosing SFA indiscriminately.