• Proceedings of the Korea Concrete Institute Conference
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• 1993.04a
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• pp.176-181
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• 1993

Recent increasing traffic volumes have made many bridges on highway be widened. Depending on the construction method of bridge widening, several undesirable problems have been arisen with the additional stresses resulting from de-staging of new bridge and the difference of the amount of creep and shrinkage between new and existing bridge. The main focus of this paper is given to investigate the variation of the adhesive strength of steel bar and construction joints of new and old concrete slab. The result shows that repeated vibration loadings was caused some bad effects on the construction joints between new and existing bridges.

• Proceedings of the Korea Concrete Institute Conference
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• 1994.04a
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• pp.13-18
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• 1994

Most widened bridges have been constructed by the joining-construction method that makes new and existing bridge structurally single structure. However, joing-construction method has several problems in design and construction viewpoint. Therefore, this study is conducted in order to investigate structural behavior of widened RC slab and traffic-induced vibration of existing bridge during placing and curing of new concrete by the prototype flexural fatigue test. From the results of this study, it is shown that stress-concentration and slip occur between concrete and reinforcing rod at joint section but the reduction of load carrying capacity and of fatigue strength is negligible according to the traffic-induced vibration as well as the difference of construction method. A reasonable construction method for the bridge widening which takes into account the effects of the traffic-induced vibration and S-N curve for the widened bridge are also proposed.

• Journal of Korean Foot and Ankle Society
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• v.4 no.2
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• pp.61-66
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• 2000

Purpose: To evaluate the clinical validity of percutaneous screw fixation in Maisonneuve fracture. Material and Methods: Out of 5 Maisonneuve fracture patients hospitalized in the department of orthopedic surgery of Seigang hospital from February 1995 to May 1998, 4 patients were treated with percutaneous screw fixation and 1 patient was treated with percutaneous screw fixation and repair of deltoid ligament altogether. The results were evaluated on the clinical and radiological finding. Results: In all cases, the range of motion of ankle joint was normal, the complication such as postoperative pain and post-traumatic arthritis were not found. Widening of medial clear space or talar shift were not found in the follow up X-ray and tibiofibular distance, compared with normal ankle joint was same on follow up CT. Conclusion: Percutaneous screw fixation is simple, less invasive and more effective method in the treatment of Maisonneuve fracture.

• Journal of Korean Foot and Ankle Society
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• v.16 no.2
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• pp.79-86
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• 2012

Calcaneal fractures account for 2% of all fractures and approximately 60 to 70% of tarsal fractures. These fractures typically are the result of high-energy injury, such as a motor vehicle accident or a fall from a height. The potential for disabling malunion following intrarticular displaced calcaneal fracture is high, regardless of treatment. Fracture displacement typically results in loss of hindfoot height, varus and widening of the hindfoot, with possible subfibular impingement and irritation of the peroneal tendon and/or sural nerve. Frequently, subtalar joint develops posttraumatic arthritis. In symptomatic patients with calcaneal malunion, systemic evaluation is required to determine the source of pain. Nonsurgical treatment, such as activity and shoe modification, bracing, orthoses, and injection, is effective in many patients. Surgical treatment may involve simple ostectomy, subtalar arthrodesis with or without distraction, or corrective calcaneal osteotomy. A high rate of successful arthrodesis and of patient satisfaction has been reported with surgical manamgent.

• Current Industrial and Technological Trends in Aerospace
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• v.8 no.2
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• pp.136-144
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• 2010

The utilization of UAV and the activities of diverse widening, now the challenge was how to operate and integrate UAV safely in the NAS. The purpose of this study is to look around the trend for interoperability of UAV in the NAS and to provide its implications and the future direction of integrated operating airspace focusing on U.S. where R&D and demand of UAV are the most in the world.

• Journal of Environmental Health Sciences
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• v.24 no.3
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• pp.35-40
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• 1998

This study was conducted to examine the pathological changes of rat peripheral nervous system during exposure to tellurium known to be a demyelinating agent by using teasing nerve fiber method and quantitative light microscopic analysis by image analyzer. The pellet containing 1.2% of tellurium were fed for 3, 5, 7, 9, 13 days to male wistar rats (21 days old) and then neurologic symptom and the feature of nerve fiber myelination were studied. From this study, following results were obtained. In 3 days treated group, it showed various neurologic symptom and teased nerve fiber showed slight irregularity of the myeline sheath. In 5 days and 7 days treated groups, it showed the segmental demyetination in larger size fiber and widening of nodes of ranvier. In 9 days and 13 days treated groups, the remyelinated fibers were observed and it was generally small in size. We consequently suggest that teasing nerve fiber method and quantitative analysis of nerve fiber were useful pathologic screening method of neurotoxicity of the peripheral nervous system.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.04a
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• pp.265-268
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• 2005

A new method for measurement of the pore size in a nanohoneycomb structure using atomic force microscopy (AFM) was proposed. Porous type anodic aluminum oxide (AAO) was fabricated as a nanohoneycomb structure to measure the pore size. For measuring pore sizes from AFM images, a criterion was set in porous type AAO. The pore sizes from AFM images were compared with those from SEM images, and the results showed good agreement. The relationship between the pore size and widening time was found to be linear in the range of this study. It was understood as the synchronized effects of the impurity gradient in outer oxide of AAO, mechanical packing and mass transfer increase.

• Journal of Environmental Impact Assessment
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• v.9 no.4
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• pp.315-322
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• 2000

Environmental Impact Assessment(EIA) was first formally established in the Korea in 1981. Subsequently there has been a rapid growth in EIA activity, and over one hundred fifty environmental impact statements are now published in Korea each year. Although EIA now has almost 20 years of history in the Korea, elsewhere the development of roles and practice is more recent. Development is moving apace in many countries, including the Japan and the EU Member States. Such progress has not been without its problems, and a number of the current issues in EIA-scope of the assessment, the relative roles, the quality of assessment and monitoring and auditing after decision, and so on- are highlighted. So the purpose of this article is to reform the EIA roles and process, in extending the scope of activity, and assessing effectiveness. This article suggested improving the effectiveness of project assessment, widening the scope: stretegic environmental assessment, and extending EIA to project design process, environmental monitoring and feedback system.

• Journal of Chest Surgery
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• v.10 no.2
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• pp.349-354
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• 1977

Mediastinoscopy is a surgical endoscopic technique used mainly for examination and biopsy of lesions of the superior and posterior middle mediastinum. It is particularly concerned with diseases that primarily or secondary involve the paratracheal and parabronchial lymphatics. A total of 18 cases of mediastinoscopy are presented with a detailed analysis of indications and results. Of these mediastinoscopy was positive in i0 [56%] and negative in 8 [44%]. The 10 positive mediastinoscopies were diagnostic in 4 patients with malignant lymphoma, 5 patients with carcinoma of the lung, one patient with active pulmonary tuberculosis. Of 8 negative mediastinoscopies, one was inoperable due to recurrent laryngeal nerve involvement, 7 patients were subjected to radical resection. Complications of mediastinoscopy were developed in 2 cases, one was minimal degree of subcutaneous emphysema on anterior chest wall, and the other was widening of right mediastinal border due to hematoma. Two complications were completely absorbed after 7 days.

• Journal of Chest Surgery
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• v.24 no.5
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• pp.522-528
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• 1991

A successful repair of aortic dissection of descending thoracic aorta was performed in a 48 year old man. The patient was visited ER because of abruptly onset chest pain. On admission, Chest film showed mediastinal widening and undertaken chest CT, echocardiogram and angiogram There was evidence of dilation on descending aorta with internal separation of intimal calcification. Aneurysmal sac with dissection was noted from just below left subclavian artery to 2cm above of diaphragm. He underwent thoracotomy and the impending ruptured aneurysm of the aorta was replaced with a Woven Dacron graft[20Yo Albumin preclotted] using LA-femoral bypass. Postoperative course was uneventful.