• Korean Journal of Construction Engineering and Management
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• v.25 no.1
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• pp.42-49
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• 2024

In recent years, the construction industry has diligently focused on improving the quality and safety of buildings through smart technologies. However, there is a growing trend of leakage defects, especially in educational facilities, due to aging. The objective of this study is to analyze the causes of these defects in educational environments using the Fault Tree Analysis (FTA) technique and propose preventive measures based on the findings. The FTA technique is explained through a review of domestic literature, and data from the Educational Support Center from 2019 to 2021 are examined to identify major defects. The construction of the Fault Tree (FT) for leakage defects resulted in the identification of 12 basic events. Subsequently, a comprehensive understanding of the causes of leakage is achieved through FTA analysis, leading to the identification of the primary causes of defects. Leakage defects accounted for 46.8% of all reported issues in educational facilities, with roof (ceiling) leaks being the most common problem. FTA analysis revealed that poor substrate treatment was the main cause of roof (ceiling) leaks, which could be attributed to cracks in the waterproof layer, joint cracks, and microvoids in the waterproof layer. The primary achievement of this research is to provide essential data for preventing leakage defects in educational facilities and developing preventive measures through the FTA technique. These results are expected to significantly enhance the management of educational facilities and the prevention of leakage issues.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.20 no.2
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• pp.112-126
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• 1998

In dentistry, bony defects can be formed by cyst, tumor, inflammation, trauma and surgery in maxilla and mandible. If the overlying soft tissue invades and preoccupies the jaw bony defects, regenerated bony tissue same as adjacent bone can not replace whole space of the defects, thus preventing osteogenesis from occurring. Guided bone regeneration(GBR) is based on the prevention of overlying soft tissue from entering the bony defect during the initial healing periods. E-polytetrafluoroethylene(e-PTFE) is one of an effective and widely used barrier membrane for GBR, but it has the disadvantages such as surgical removal and high price. To overcome such disadvantages of e-PTFE, many investigators have proposed various absorbable barrier membranes. Inexpensive oxidized cellulose($Surgicel^{(R)}$) membrane was shown to have potential for use as an absorbable barrier membrane for regenerative procedure and it would not require surgical removal. The purpose of this study is to investigate the absorption periods of oxidized cellulose at the implant site and usefulness as a mechanical barrier, preventing the ingrowth of the overlying soft tissue into the bony defects. Two bony defects were made in each tibia of a dog using drill and one defect covered with oxidized cellulose and the other covered with periosteum directly as control. The experimental animals were sacrificed at 1st-7th, 10th, 14th, 21th, 28th day postoperatively, Inspection of the specimens was done to evaluate gross changes. Specimens were examined histopathologically by hematoxylin-eosin and Masson's trichrome staining under light microscope. The results were as follows : 1. There was no significant differences of inflammatory reaction between the experimental and the control group. 2. The resorption of oxidized cellulose was almost completed within 14th day. 3. Histologically, bone formation in the experimental group was somewhat more than that of the control group at 10th, 14th, 21th and 28th day postoperatively. The bone forming pattern of the experimental group was more regular than that of the control group. 4. There was no evidence of soft tissue invasion into the bony defect in the experimental group. In conclusion, oxidized cellulose membrane might be used as an alternative absorbable barrier membrane to prevent overlying soft tissue invasion into the bony defects.

• Archives of Plastic Surgery
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• v.37 no.3
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• pp.213-219
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• 2010

Purpose: Iodine has been used for the prevention or management of wound infection as a topical agent. Although iodine was widely used mainly by Betadine$^{(R)}$ and cadexomer iodine, there was no comparative study on the efficacies of dressing methods of iodine. And also it's wound healing effect was not yet clear. The purpose of this study is to compare antibacterial effects and wound healing effects associated with various dressing methods of iodine on infected full thickness skin defect in the mouse. Methods: One full thickness skin defects in the mice (n=60) were developed on the back and left open for twenty-four hours. Sixty mice were divided into four groups : group S (dressing with Betadine$^{(R)}$ soaking, n=15), group T (dressing with Betadine$^{(R)}$ topping, n=15), group I (dressing with Iodosorb$^{(R)}$, n=15), group G (control group, dressing with dry gauze, n=15). The size of the wound defects and the grades of wound healing were evaluated in 4, 7, 10 days, and antibacterial effect was evaluated with restricted zone in Mueller Hinton agar by disk diffusion method. Results: After the wound was left open for twenty-four hours, many Staphylococcus aureus were cultured. The wound defect size was decreased in order of Betadine$^{(R)}$ soaking, Iodosorb$^{(R)}$, Betadine$^{(R)}$ topping and gauze dressing group in all days, but difference among experimental groups was not statistically significant. The grade score of wound healing was increased in order of Betadine$^{(R)}$ soaking, Iodosorb$^{(R)}$, Betadine$^{(R)}$ topping and gauze dressing group, and the difference was statistically significant. Antibacterial effect for S. aureus was increased in order of Iodosorb$^{(R)}$, Betadine$^{(R)}$ soaking, Betadine$^{(R)}$ topping and gauze dressing group, and the difference was statistically significant. Conclusion: Selection of the effective dressing method of iodine for infected wounds remains a controversial decision. According to this study, Iodosorb$^{(R)}$ may be most effective method for antibacterial effect and Betadine$^{(R)}$ soaking may be most effective method for infected wound healing. However, further study is necessary to evaluate the clinical efficacy of dressing methods of iodine and to search for the mechanisms that explain their effects.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.6
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• pp.1274-1279
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• 2011

The purpose of this paper is to present the manufacturing defect and damage pattern of a 3 phase 22.9/3.3kV oil immersed transformer, as well as to present an objective basis for the prevention of a similar accident and to secure data for the settlement of PL related disputes. It was found that in order to prevent the occurrence of accidents to transformers, insulating oil analysis, thermal image measurement, and corona discharge diagnosis, etc., were performed by establishing relevant regulation. The result of analysis performed on the external appearance of a transformer to which an accident occurred, the internal insulation resistance and protection system, etc., showed that most of the analysis items were judged to be acceptable. However, it was found that the insulation characteristics between the primary winding and the enclosure, those between the ground and the secondary winding, and those between the primary and secondary windings were inappropriate due to an insulating oil leak caused by damage to the pressure relief valve. From the analysis of the acidity values measured over the past 5 years, it is thought that an increase in carbon dioxide (CO2) caused an increase in the temperature inside the transformer and the increase in the ethylene gas increased the possibility of ignition. Even though 17 years have passed since the transformer was installed, it was found that the system's design, manufacture, maintenance and management have been performed well and the insulating paper was in good condition, and that there was no trace of public access or vandalism. However, in the case of transformers to which accidents have occurred, a melted area between the upper and the intermediate bobbins of the W-phase secondary winding as well as between its intermediate and lower bobbins. It can be seen that a V-pattern was formed at the carbonized area of the transformer and that the depth of the carbonization is deeper at the upper side than the lower side. In addition, it was found that physical bending and deformation occurred inside the secondary winding due to non-uniform pressure while performing transformer winding work. Therefore, since it is obvious that the accident occurred due to a manufacturing defect (winding work defect), it is thought that the manufacturer of the transformer is responsible for the accident and that it is lawful for the manufacture to investigate and prove the concrete cause of the accident according to the Product Liability Law (PLL).

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.11
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• pp.4535-4538
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• 2014

Objective: To explore the value of porous titanium alloy plates for chest wall reconstruction after resection of chest wall tumors. Materials and Methods: A total of 8 patients with chest wall tumors admitted in our hospital from Jan. 2006 to Jan. 2009 were selected and underwent tumor resection, then chest wall repair and reconstruction with porous titanium alloy plates for massive chest wall defects. Results: All patients completed surgery successfully with tumor resection-induced chest wall defects being $6.5{\times}7cm{\sim}12{\times}15.5$ cm in size. Two weeks after chest wall reconstruction, only 1 patient had subcutaneous fluidify which healed itself after pressure bandaging following fluid drainage. Postoperative pathological reports showed 2 patients with costicartilage tumors, 1 with squamous cell carcinoma of lung, 1 with lung adeno-carcinoma, 1 with malignant lymphoma of chest wall, 2 with chest wall metastasis of breast cancers and 1 with chest wall neurofibrosarcoma. All patients had more than 2~5 years of follow-up, during which time 1 patient with breast cancer had surgical treatment due to local recurrence after 7 months and none had chest wall reconstruction associated complications. The mean survival time of patients with malignant tumors was ($37.3{\pm}5.67$) months. Conclusions: Porous titanium alloy plates are safe and effective in the chest wall reconstruction after resection of chest tumors.

• Journal of the Korea Safety Management & Science
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• v.20 no.2
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• pp.9-20
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• 2018

This study is empirically intended to look into the effects of HVAC management on condensation cause and prevention in indoor swimming pools. The findings are summarized as follows. First, the experience of condensation in indoor swimming pools showed that 132 out of 142 people in total experienced the condensation in indoor swimming pools, which they had a high experience rate of 92.3%. For the location of condensation, the wall joints were 46.8% and the windows were 34.5%, which a total of 72.3% occurred in the wall joints and windows. Second, the effect of construction design, HVAC management and building construction on the cause of condensation in indoor swimming pools showed that building construction had an effect on the cause and location of condensation depending on the seasonal time, partially adopting hypothesis 1. Third, the effect of condensation-causing factors on condensation-preventing factors in indoor swimming pools showed that condensation had a close relationship with air and temperature conditions depending on the time and location of condensation, adopting hypothesis 2. As for the above-stated findings, the HVAC management in indoor swimming pools is an important concern factor that continues to cause condensation despite the development of advanced construction materials. Especially, building construction is a main factor that has a direct effect on condensation in the HVAC management of facilities. This implies that the window management is important in maintaining the wall joints - which can suppress the selective use and defect occurrence of construction materials - or confined spaces for a long time.

• Archives of Plastic Surgery
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• v.35 no.2
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• pp.214-218
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• 2008

Purpose: Reconstruction of microtia using costal cartilage graft is commonly used technique nowadays. The chest wall depression at the donor site after the graft, however, has been noticed in many articles. Prevention or correction technique for the depression at the donor site also has been reported and we also have been concerned about the problem. This article is a case report about a new technique preventing chest wall depression after costal cartilage graft. Methods: We selected total 15 microtia patients who visited our clinic, from December 2005 to July 2007. They were 10 male and 5 female patients and the mean age was 11.9 years. The average follow up period was 9.2 months(2 to 15 months). We used 6, 7, and $8^{th}$ costal cartilage for microtia reconstruction. And then we turned over pivot of cartilage resection margin, after bihalving costal cartilage involving about 5-6 cm of $6^{th}$ and $7^{th}$ rib bone. After microtia reconstruction, chest donor sites were evaluated by physical examination and radiography. Results: Postoperative depression at the donor site was much less when the costal cartilage turnover technique was performed. Postoperative physical examination and three dimensional reconstruction CT showed that the rest part of rib bone was turned over and it supported the soft tissue defect during respiration. Conclusion: We expect that the turnover rib bone will not be absorbed after graft, as well as offering mechanical support, compared to the other reports.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.36 no.4
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• pp.71-81
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• 2020

The purpose of this study is to propose the planning methods for pollution prevention in the initial design stage by identifying the pollution phenomena on the exterior of the building. It is important to catch the problem early on because exterior troubles begin with an initial design defect and causes rapid aging. The scope of this study is seoul public borough offices that should be sustainable for long as landmark located at the center of the district. Field survey was conducted three times in six months. Twenty-six borough offices were diagnosed with three levels of contamination through visual inspection and the contaminated locations, types, materials, and characteristics were checked. Fourteen common contaminated locations were identified in the first and intensively rechecked in the second. Five locations vulnerable to contamination were designated and the contamination and cleanliness situations were checked by location in the third. As a result, main polluted types and locations are sloping wall, upper wall, protruded wall, canopy, and wall under window. The key to avoiding these pollution problems is to minimize the horizontal plane on which dust can be deposited. In other words, it can be considered variously by shape and location, such as the slope of the horizontal plane, the floating of the surface, the installation of the roof surface, and the vertical louvers. And throating plans and material plans suitable for each location are presented. Various methods of the shape and location, material are expected to use as useful basic data for preventing pollutions during the initial design stage.

• The Journal of Korean Medicine
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• v.23 no.3
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• pp.119-133
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• 2002

Objectives : This study was designed to investigate significant differences between the first attack and reattack groups to form fundamental data for decreasing recurrence and secondary prevention of stroke. Methods : I studied 204 patients admitted within 7 days of onset, after the diagnosis of stroke, in the Oriental Medical Hospital of Dongeui University from February to July in 2001.compared the reattack group with the first attack group for risk factors, clinical symptoms and progress, average mark and degree of improvement in Activity Index. Results : 1. Meaningful risk factors associated with the reattack group were male sex, a past history of hypertension and transient ischemic attack, and a family history of stroke. 2. The reattack group had conscious or cognitive disorder in early stage of onset, dysphagia, constipation, urinary incontinence, visual field defect in acute stage, high blood pressure and tachycardia in abnormalvital sign in acute stage, neuropsychosis, shoulder pain and rigidity, and pneumonia in complications more than the first attack group. 3. In Activity Index, the average mark of reattack group was lower than that of the first stroke group and improvement of the reattack group was delayed compared with the first attack group. Conclusions : The reattack group had more severe symptoms and clinical progress than the first attack group.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.1
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• pp.293-299
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• 1997

Wiskott-Aldrich syndrome is a rare, hereditary disease occurring in males and was first described in 1937. It is characterized by cutaneous eczema, thrombocytopenic purpura and an increased susceptibility to infection due to an immunologic defect. Patients with Wiskott-Aldrich syndrome have a poor antibody response to polysaccharide antigens, low levels of IgM and high levels of IgA and IgE in serum. Oral manifestations of Wiskott-Aldrich syndrome was observed a spontaneous gingival bleeding, palatal petechiae, ulcer and gingival hyperplasia. We report on dental treatment of a 5 years old boy with severe spontaneous gingival bleeding and ulcer suffered from Wiskott-Aldrich syndrome. Prophylactic antibiotics to prevent infection and all potential measures including platelet concentrate therapy to prevent postoperative bleeding should be undertaken. Good oral hygiene should be maintained for prevention of infection by oral normal flora.