• 제어로봇시스템학회:학술대회논문집
• /
• 1996.10a
• /
• pp.133-136
• /
• 1996

The nozzle dam task is essentially needed to maintain and repair nuclear power plants. For this task, an 8-dof redundant robot is studied with a local path-planning method[l] which is effective to find the optimal joint path in the constrained environment. In this paper, the method[l] is improved practically with the weight matrix and efficient algorithm to find working set. The effectiveness of the proposed method is demonstrated by simulation and animation.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.25 no.1
• /
• pp.115-126
• /
• 2001

In this paper, through a series of comparative experiments, effects of two different cure processing methods, cocure and precure, on the mechanical properties of honeycomb core materials for aircraft applications are considered. Mass of moisture accumulated into the closed cells of the sandwich panel specimen from the measured mass of moisture diffused to the full saturation state into the elements(skin, adhesive layer, Nomex honeycomb), consisting the honeycomb sandwich specimen has been calculated. Water reservoir of 70$\^{C}$ was used to have specimens absorb moisture to see the influence of moisture absorbed into sandwich panel on its mechanical properties. For the repair condition holding for 2 hours at 177$\^{C}$(350℉) temperature, a pressure due to the vapor expansion in each cell of the sandwich panel, which may result in the local separation of the interface between laminated skin and the surface of the honeycomb, has been estimated by vapor pressure-temperature relation from the thermodynamic steam table and compared to the pressure from the ideal gas state equation. The bonding strengths of the laminated skins on the flat surface of the Nomex honeycomb have been compared by the flatwise tension test and climbing drum peel test performed at room temperature for dry, wet and wet-repair specimens, respectively.

• Journal of Chest Surgery
• /
• v.17 no.3
• /
• pp.356-361
• /
• 1984

During the period from January 1982 to June 1984 we implanted permanent pacemakers in 18 patients who received open heart surgery at Yonsei University Hospital. 1.In 11 patients, open heart surgery was performed at Yonsei University Hospital and new surgical induced heart blocks were developed and implantations of permanent pacemaker were done. 2.Total 1035 open heart surgeries were done and implantations of pacemaker were performed in 11 cases. [1.06%]. After total correction of TOF [215 cases] implantations of pacemaker were done in 3 cases. [1.4%] Implantations of pacemaker were 0.37% after VSD repair, 0.78% after ASD repair, 5.9% after ECD repair, 0.48% after MVR and 2.0% after AVR. 3.Causes were complete A-V block, sick sinus syndrome and A-V dissociation. 4.Heart blocks were developed immediately after bypass stop in 8 patients. 5.Implantations of pacemaker were done at more than 2 weeks after open heart surgery. 6.Local anesthesia was done in adult and general anesthesia in infants. Locations of pulse generator were subxiphoid, subcostal & subclavian. Position of pulse generator was between subcutaneous fat layer and muscle layer. 7.Types of pulse generator were VVI, VDD and AAI. 8.The postoperative complications included infection, pacing failure, sensing failure and lead dislodgment.

• The Journal of Economics, Marketing and Management
• /
• v.10 no.5
• /
• pp.7-14
• /
• 2022

Purpose: This study discusses efficient operation plans in terms of public rental housing maintenance in terms of LH, a major supplier. Research design, data, and methodology: After reviewing problems related to the maintenance and management of public rental housing discussed in several previous studies, problems in technology setting for repair maintenance costs for public rental housing, lack of public assistance for maintenance and management of public rental housing, management of housing funds, and lack of role of local governments in the supply and repair of public rental housing were derived. Based on this, the researcher conducted using literature research methods to present relevant improvement measures based on reasonable arguments. Results: this study presented four operational plans related to (1) realization of repair costs for public rental housing, (2) a public subsidy system for covering the maintenance costs for public rental housing, (3) efficient operation of the Housing City Fund, and (4) establishment of the public rental housing. This study aims to provide a foundation for the qualitative growth of the domestic public rental housing system. Conclusions: With this study, it is expected that social interest in maintenance of public rental housing centered on LH will be amplified to improve the quality of maintenance problems of public rental housing.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2022.04a
• /
• pp.87-88
• /
• 2022

For an earthquake-safe urban environment, the Republic of Korea conducts seismic performance evaluation in accordance with laws and guidelines to assign safety ratings and implement necessary management measures such as repairs and reinforcements. In the seismic performance evaluation result, structures lacking in preparation for earthquakes are prioritized and classified into measures such as repair, reinforcement, or careful observation to respond to physical risks such as earthquakes. Such repair and reinforcement work is not a one-time thing, but it is necessary to further enhance the effect through continuous follow-up observation. In this study, the location of the vertical and horizontal displacement measuring part of the construction part is displayed so that the post-construction status of the reinforcement construction part can be visually checked by identifying the problems in the process of post-monitoring in 2022 for the maintenance and reinforcement work of local governments' public facilities carried out in 2021. We propose a plan to institutionalize the installation of, inspection tools, and crack gauges at certain locations in the construction department, and to have facility managers periodically inspect and manage them with a smartphone program or the 'Facility Autonomous Safety Inspection' app.

• Journal of the Architectural Institute of Korea Planning & Design
• /
• v.34 no.1
• /
• pp.33-40
• /
• 2018

The society for conservation of local historical properties in Korea originated in Japan. It was transplanted by Joseon Governor-General to represent their positions in the field of the conservations of the cultural properties. Also the society for conservation of local historic properties represented the positions of the provincial government office because the representatives of that societies were the chief of local government offices. At that time, the fundamental concept of the historical property conservations was not settled, so they accomplished the conservation activities as the necessary way for themselves.They often made a proposal about repairs for conservation of historical building and suggested a application for the national budget. And they contributed to carry out the repair works of the historical properties in the early Japanese colonial period. But they was usually used to invigorate the tourism and to publicize the regional characteristics through the historical properties. Although the societies were privately-managed as a matter of form, they were governmentally-managed as a matter of fact. It was the limits of the societies for conservation of local historical properties at that time.

• Journal of Chest Surgery
• /
• v.27 no.10
• /
• pp.888-892
• /
• 1994

Acquired, traumatic tracheoesophageal fistula [TEF] is rare and difficult problem to manage. This 55 years old man met with a roller accident of a tractor. During accident, he received a penetrating injury on the left upper sternal border. At local clinic, he received closed thoracotomy drainage [CTD]for relief of pneumothorax[left]. Three days after CTD, he complained abdominal pain and hematemesis. The endoscopy revealed large ulcer at the stomach, so he received subtotal gastrectomy. On 10th day post subtotal gastrectomy, he developed aspiration and coughing from a TEF. The esophagogram showed large TEF at the mid-trachea level. So he transfered to our hospital for operation. This patient was operated on for late TEF three weeks after injury. We have used absorble 4-0 Vicryl sutures to repair trachea. We repair all esophageal injuries with two layers of nonabsorbable silk suture. Where suture line on the esophagus, the strap muscle was interposed for reinforcement. And for feeding, the feeding jejunostomy was performed. Postoperatively the osteomyelitis of the manubrium site was developed, so on the 30th postoperative day, an ostectomy of manubrium, both clavicle and fight 1st, 2nd ribs, and the pectoralis major musculo-cutaneous flap coverage were performed.

• Transactions of the Korean Society of Pressure Vessels and Piping
• /
• v.11 no.2
• /
• pp.51-60
• /
• 2015

Local wall thinning and integrity degradation caused by several mechanisms, such as flow accelerated corrosion, cavitation, flashing and/or liquid droplet impingement, is a main concern in secondary steam cycle piping system of nuclear power plants in terms of safety and operability. Thinned pipe management program (TPMP) has being developed and optimized to reduce the possibility of unplanned shutdown and/or power reduction due to pipe failure caused by wall thinning. In this paper, newest technologies, standards and regulations related to the integrity assessment, repair and replacement of thinned pipe component are reviewed. And technical improvement items in TPMP to secure the reliability and effectiveness are also presented.

• Journal of Korean Neurosurgical Society
• /
• v.58 no.6
• /
• pp.504-507
• /
• 2015

Objective : Our aim was to evaluate the histopathological effects of tissue adhesives on peripheral nerve regeneration after experimental sciatic nerve transection in rats and to search whether these tissue adhesives may possess a therapeutic potential in peripheral nerve injuries. Methods : This experimental study was performed using 42 female Wistar-Albino rats distributed in 6 groups subsequent to transection of right sciatic nerves. Group I underwent external circumferential neurolysis; Group II received suture repair; Group III had local polymeric hydrogel based tissue adhesive administration; Group IV received suture repair and polymeric hydrogel based tissue adhesive application together; Group V had gelatin based tissue adhesive application and Group VI had suture repair and gelatin based tissue adhesive together. After a 6-week follow-up period, biopsies were obtained from site of neural injury and groups were compared with respect to histopathological scoring based on inflammatory, degenerative, necrotic and fibrotic changes. Results : There were remarkable differences between control group and study groups with respect to inflammation (p=0.001), degeneration (p=0.002), necrosis (p=0.007), fibrosis (p<0.001) and vascularity (p=0.001). Histopathological scores were similar between study groups and the only noteworthy difference was that Group V displayed a lower score for necrosis and higher score in terms of vascularization. Conclusion : Our results imply that tissue adhesives can be useful in repair of peripheral nerve injuries by decreasing the surgical trauma and shortening the duration of intervention. Results with gelatin based tissue adhesive are especially promising since more intense vascularity was observed in tissue after application. However, trials on larger series with longer durations of follow-up are essential for reaching more reliable conclusions.

• Journal of Korean Foot and Ankle Society
• /
• v.10 no.2
• /
• pp.173-178
• /
• 2006

Purpose: The purpose of this study is to assess the clinical and radiological results of the early primary repair for acute ankle sprains. Materials and Methods: From October 2002 to September 2005, nine patients with acute ankle sprain were analyzed. Among them, eight patients took the inversion stress X-ray at local clinics, and the mean talar tilting angle was 28 degrees. We observed avulsion fragment near lateral malleolus in the other. The average age at the time of operation was 24 years and average follow-up period was 29 months. We evaluated postoperative symptoms by Hasegawa's clinical rating system, postoperative complications, and compared the talar tilting angle and anterior draw distance between both ankles at the final follow-up X-rays. Results: Anterior talofibular ligament was ruptured at fibula in 4, at midsubstance in 3, at talus in 1 and at fibula and midsubstance simultaneously in 1. Calcaneofibular ligament was ruptured at fibula in 3 including a case of avulsion fracture, at midsubstance in 2, and at calcaneus in 4. And posterior talofibular ligament was ruptured at midsubstance in 2. Clinical results were rated as excellent in all. We did not find major postoperative complications except for one sural nerve irritation. Both (injured ankle/uninjured ankle) talar tilting angle averaged 6.8/8.2 degrees and anterior draw distance averaged 2.9/3.7 mm at final follow-up X-rays. Conclusion: Early primary repair is recommended for treating acute severe ankle sprains and in case found avulsion fracture in X-ray taken after ankle sprain.