• Computers and Concrete
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• 제9권2호
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• pp.99-118
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• 2012

Marine Structures are very costly and need a continuous inspection and maintenance routine. The most effective way to control the structural health is the application of an expert system that can evaluate the importance of any distress on the structure and provide a maintenance program. An extensive literature review, interviews with expert supervisors and a national survey are used to build a decision support system for concrete structures in sea environment. Decision trees are the main rules in this system. The system input is inspection information and the system output is the main cause(s) of distress(es) and the best repair method(s). Economic condition, severity of distress, distress situation, and new technologies and the most repeated classical methods are considered to choose the best repair method. A case study demonstrates the application of the developed decision support system for a type of marine structure.

• 한국도로학회논문집
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• 제14권3호
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• pp.59-67
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• 2012

본 연구는 아스팔트 포장 파손을 복구하는 보수재료에 대한 연구이다. 현재 국내에서 사용되고 있는 네가지 종류 재료들에 대하여 실내 및 현장시험을 실시하였다. 실내 시험으로 마샬안정도시험, 간접인장시험, 수침잔류 안정도시험, 휠트랙킹 시험을 실시하였다. 또한 성능시험으로는 기존 아스팔트 콘크리트 혼합물과의 수평전단강도시험을 실시하였다. 현장시험은 아스팔트 포장 도로상에서 차량바퀴가 통과하는 지점에 패칭 슬래브를 제작하여 차량 통과에 따른 공용 결과를 관찰하였다. 실내시험 결과는 현재 적용되고 있는 설계 재료들의 기준은 수침잔류 안정도를 제외하고 만족하였다. Type C가 가장 높은 수평전단강도를 나타냈다. 그러나 시공후 10일 이후부터 소성변형과 탈리와 같은 파손이 발생하였다. 따라서 현재 사용되고 있는 상온보수 재료들을 현장에 적용할 경우에 우수한 성능을 기대할 수 없어서 조기파손을 방지할 수 있는 새로운 시험방법의 개발과 적용이 필요하다.

• Computers and Concrete
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• 제6권4호
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• pp.281-303
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• 2009

The lack of safety of bridge deck structures causes frequent repair and strengthening of such structures. The repair induces great loss of economy, not only due to direct cost by repair, but also due to stopping the public use of such structures during repair. The major reason for this frequent repair is mainly due to the lack of realistic and accurate assessment system for the bridge decks. The purpose of the present research was to develop a realistic expert system, called Bridge Slab-Expert which can evaluate reasonably the condition as well as the service life of concrete bridge decks, based on the deterioration models that are derived from both the structural and environmental effects. The diagnosis assessment of deck slabs due to structural and environmental effects are developed based on the cracking in concrete, surface distress and structural distress. Fuzzy logic is utilized to handle uncertainties and imprecision involved. Finally, Bridge Slab-Expert is developed for prediction of safety and remaining service life based on the chloride ions penetration and fick's second law. Proposed expert system is based on user-friendly GUI environment. The developed expert system will allow the correct diagnosis of concrete decks, realistic prediction of service life, the determination of confidence level, the description of condition and the proposed action for repair.

• Journal of Chest Surgery
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• 제21권3호
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• pp.526-530
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• 1988

Acquired communicated fistula between the esophagus and respiratory system are infrequent and they are caused by carcinoma, trauma, infection and traction. This report reviews the feature of acquired esophagobronchial fistula[that developed spontaneously]. Patient is 34 year old man with excellent result by surgical intervention. The surgical procedures consist of division and repair of the fistula. Clinically and radiologically, the patient is free from coughing after drinking, substernal distress, esophagorespiratory fistula, and esophageal stricture after surgical treatment.

• Journal of Chest Surgery
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• 제32권12호
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• pp.1131-1134
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• 1999

After a penetrating thoracic injury early detection of intracardiac injury and early surgical repair when indicated are essential. A case presenting severe respiratory distress two weeks after a penetrating thoracic injury is reported. Transesophageal echocardiography showed massive pericardial effusion ventricular septal defect and mirtal regurgitation, The infundibular ventricular septal perforation was repaired using a Dacron patch the anterior mitral leaflet by interrupted sutures and the ruptured chordae of the posterior leaflet by a new chordae formation.

• 한국임상수의학회지
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• 제40권5호
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• pp.354-359
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• 2023

This case report describes the clinical presentation and successful surgical repair of a diaphragmatic hernia-related small intestinal strangulation in a neonatal foal. A nine-day-old foal presented with colic signs and respiratory distress. History taking showed that the dam of the foal experienced difficulty during delivery, and the owner assisted in delivery by pulling on the foal. Radiography and ultrasonography confirmed the diaphragmatic rent and the presence of a small intestine within the thoracic cavity. Surgical intervention was required to repair the diaphragmatic defect and address the intestinal strangulation. The diaphragm was reconstructed, and the nonviable incarcerated portion of the small intestine was resected and anastomosed using an end-to-end technique. This unusual case report provides insights into the surgical repair and outcomes of an acquired diaphragmatic hernia in a neonatal foal.

• 한국도로학회논문집
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• 제8권2호
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• pp.49-54
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• 2006

The purpose of this study was to determine the effect of expansion joint spacing (slab size) on the life cycle costs of owning Portland Cement Concrete (PCC) airfield pavements. Previous research has shown that slab size has a statistically significant impact on pavement performance. A probabilistic life cycle cost analysis was performed to determine if the effect of slab size on pavement performance would affect the total cost of ownership of PCC pavements. Data from 48 Pavement Condition Index (PCI) inspections of military and civilian airfields were used to develop probability-of-distress-by-condition curves, which were then used to develop probabilistic cost-of-repair-by-condition curves. A present worth life cycle cost analysis was then performed for various slab sizes, using construction costs, rehabilitation costs, and maintenance costs. Maintenance costs were determined by assuming a condition deterioration rate appropriate for each slab size and applying the cost-by-condition curves. The probabilistic cost-of-repair-by-condition curves indicated that smaller slabs are more expensive to repair on a unit cost basis. Life cycle cost analysis showed that larger slabs have a higher total cost of ownership than smaller slabs due to a faster rate of deterioration.

• 한국도로학회논문집
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• 제18권5호
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• pp.21-29
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• 2016

PURPOSES : The purpose of this study is to suggest a specific investigation guideline to decide priority of repairing old concrete pavements that pile up substantially. METHODS : In this study, a principle of division of homogeneous sections was proposed to reflect the characteristics of the pavement reasonably in the specific investigation results. In addition, a checklist and guideline of field investigation were suggested for the old concrete pavement sections, which require inspection toward their durability and structural performance. Furthermore, the items of laboratory test necessary to the old concrete pavement were suggested based on the existing laboratory test considering characteristics of the old concrete pavement. The present condition of the old concrete pavement could be analyzed by the test results. RESULTS : A method of division of homogeneous sections suitable for the specific investigation of the old concrete pavement was suggested. The proportions of distress severity of pavement sections were compared by distress type to figure out the present state of the old concrete pavement. Scaling, durability cracking (or alkali-silica reaction), and longitudinal spalling were selected as the most severe distress types. The detailed positions of the sections were also suggested. The checklist of the specific investigation was categorized by field survey and laboratory test, and its evaluation criteria were proposed. The three types of the sections of durability cracking (or alkali-silica reaction), bridge connection, and asphalt overlay were selected as the sections of the field survey. The compressive strength, void structure, and chloride penetration depth were suggested as the items of the laboratory test. CONCLUSIONS : A fundamental level of the guideline was suggested in this study to resolve the problem of old concrete pavement. Appropriate guidelines related to the repair of the old concrete pavement should be provided by performing additional research efforts.

• Journal of Chest Surgery
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• 제21권6호
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• pp.996-1002
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• 1988

A clinical analysis was performed on 115 cases of -patent ductus arteriosus treated surgically during the period of 11 years from Aug. 1977 to Jul. 1988. at the Department of Thoracic and Cardiovascular Surgery, Chungnam National University Hospital. Among 115 cases, male was 38 and female was 77 and ages ranged 12 days to 27 years old with the average of 8 7/12 years. The major clinical symptoms on admission were frequent URI attack[77.4%], dyspnea on exertion[32.2%] and palpitation[13%]. On auscultation, continuous machinery murmurs were detected in 97 cases[84.3%] and loud systolic murmurs were detected in 18 cases[15.7%]. Preoperative electrocardiographic findings were as follows: LVH 59[51.3%], RVH 12[10.4%], BVH 16[13.9%] and WNL 28[24.3%]. Radiologically, there were increased pulmonary vascularity in 104[90.4%] and cardiomegaly 62[53.9%]. Cardiac catheterization were performed in 101 cases and mean systolic pulmonary arterial pressure was 49.84*29.7mmHg and mean Qp/Qs was 2.95k1.8. Methods of operation were multiple ligation in 96, division in 11 and transpulmonary arterial repair using cardiopulmonary bypass in 8. Complication were recannalization in 2, temporary hoarseness due to left recurrent laryngeal nerve paralysis in 3 and respiratory distress in 1 and overall mortality rate was 1.7%[2 cases].

• Advances in pediatric surgery
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• 제2권2호
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• pp.148-150
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• 1996

Transmesenteric hernia, a type of internal hernias, is a rare cause of intestinal obstruction. This intraperitoneal hernia has no sac and is formed by protrusion of a loop of bowel through an aperture in the mesentery. Incarceration leads to intestinal obstruction and subsequently, strangulation and gangrene of varing lengths of intestine. This is a case report of 4-year-old girl with transmesenteric herniation of the terminal ileum through a defect in its own mesentery. Strangulation of the affected bowel necessitates resection and primary anastomosis with repair of mesenteric defect. The postoperative course was uneventful. Acute intestinal obstruction in the absence of an external hernia and with no history of a previous surgical procedure suggests the possibility of an internal hernia, especially if the patient has a history of chronic intermittent abdominal distress.