• 한국산림과학회지
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• 제102권1호
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• pp.30-37
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• 2013

이 연구는 식생기반재 돌망태의 침식억지효과 및 녹화효과를 분석하는데 있다. 이 연구를 통하여 얻은 결론은 다음과 같다. 조사기간 중 평균침식량을 분석해 본 결과, 침식량이 가장 많은 순으로 보면 곡선부에서의 일반돌망태시공지(5,840 $cm^3$)>대조구(5,833 $cm^3$)>직선부의 일반돌망태 시공지(5,621 $cm^3$)>곡선부의 식생기반재돌망태시공지(4,298 $cm^3$)> 직선부의 식생기반재돌망태시공지(4,117 $cm^3$)의 순으로 나타나 식생기반재 돌망태를 시공한 것이 임도절토비탈면의 침식을 저감하는데 효과적인 것으로 분석되었다. 아울러 임도 곡선부의 식생기반재돌망태 및 일반돌망태시공지의 토양침식억지효과가 직선부보다 낮게 나타나 이러한 구조물은 곡선부보다는 직선부에 설치하는 것이 효과적일 것으로 사료된다. 조사기간 중 평균식생피복률은 곡선부에서 45(28~65)%로 나타나 동일한 기간 직선부 식생기반재돌망태시공지의 평균피복률 56(30~85)% 보다 약 11(2~20)% 낮은 값을 나타내어 직선부에서의 식생피복률이 높게 나타났다. 또한 임도절토비탈면에 시공한 식생기반재돌망태는 안정화된 이후 임도 절토 비탈면의 토양침식을 억지하는 효과로 인해 식생피복률이 증가하는데 기여하는 것으로 분석되었다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제26권4호
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• pp.391-395
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• 2000

Malignant tumors of the maxilla represent about 3-4% of head and neck malignant neoplasm and the origins are maxillary gingiva, hard palate and maxillary sinus. We are to investigate clinical features and results according to various treatment modalities of maxillary malignant tumor to get information for better treatment results. Sixty patients with malignant maxillary tumors treated at Yonsei medical center from 1992 to 1997 were studied retrospectively. They are evaluated according to clinical signs & symptoms, stages at first diagnosis, primary site, histopathologic features, treatment method, recurrence and survival rate with clinical records, biopsy results and CT radiograph. The most common primary site was maxillary sinus and most common histopathology was squamous cell carcinoma. The local recurrence rate was 18% at 5 years, neck failure was 3% and distant metastasis was 18%. Overall survival rate was 78% at 2 years and 69% at 5 years. Failure at primary site is the main problem in the curative treatment. So, to improve survival in these patients efforts should be directed toward improvement of local control.

• 한국인터넷방송통신학회논문지
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• 제17권4호
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• pp.203-208
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• 2017

최근 청년 실업 문제가 심각한 사회적 문제로 대두되면서, 대학 졸업자에 대한 원활한 사회 진출에 도움이 될 수 있도록 대학을 중심으로 졸업자에 대한 현장중심 맞춤형 교육과 산업현장에서 요구하는 경험중심 인재상을 반영한 다양한 산학협력 프로젝트가 기획되어 실시되고 있다. 그러나 이러한 노력들은 현실 취업시장 상황을 제대로 반영하지 못하고 많은 취업 실패와 시행착오를 겪고 있는 것이 현실이다. 본 연구에서는 현재 취업을 앞두고 있는 4학년을 대상으로 BLE분야 중견기업과 긴밀한 산학협력을 통해 학생 경험중심의 현장 맞춤형 소프트웨어 개발 인력양성을 위한 사업모델을 제안하여 산학협력 프로젝트를 수행하였으며, 그 결과 사업모델에 대한 사업성 평가와 약점 및 위협 요인에 대한 대응전략 분석을 통해 문제점과 실패 요인을 찾아내어 개선된 사업모델을 제안하였다.

• 대한간호학회지
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• 제50권4호
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• pp.541-553
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• 2020

Purpose: In spite of the recent application of a general infection control method, central line-associated infections is still relatively high in Korea. Central line bundle with Chlorhexidine gluconate (CHG) tegaderm dressing was reported to be effective in reducing catheter colonization and central line-associated bloodstream infections (CLABSI). Therefore, this study aimed to examine the incidences of catheter colonization occurrence and CLABSI while using Tegaderm vs. CHG Tegaderm dressings. Methods: We used a descriptive design. 400 patients who had central venous catheters were selected from four hospitals in the Korean National Healthcare-associated Infections Surveillance System. Of all subjects, 200 used Tegaderm™ (Tegaderm group), and the remaining 200 used CHG Tegaderm (CHG Tegaderm group) dressing at the catheter insertion site. Data were analyzed using the χ² test or Fisher's exact test, t-test, and logistic regression analysis using SPSS WIN 21.0. Results: In the Tegaderm and CHG Tegaderm groups, CLABSI incidences were 5.89 and 1.79 per 1,000 catheter-days, catheter colonization incidences were 3.93 and 1.43 per 1,000 catheter-days, and central line bundle compliance rates were 26.0% and 49.0%, respectively. Catheter colonization risk factors were 'reinsertion after failure' and 'Tegaderm dressing' at the central line insertion site. CLABSI risk factors were 'incomplete performance of 7 central line bundle items' and 'Tegaderm dressing' at the central line insertion site. Conclusion: A further prospective study is needed to examine the effects of central line bundle with CHG Tegaderm dressing, avoiding central line reinsertion after failure, and improving the bundle compliance in reducing catheter colonization and CLABSI.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제49권1호
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• pp.13-20
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• 2023

Objectives: Ultra-wide implants may be used as a replacement if existing implants fail. This study was conducted to evaluate the factors influencing the prognosis and failure of ultra-wide implants. Patients and Methods: This study evaluated whether sex, age, site, diameter, length, additional surgery, implant stability (primary and secondary), and reason for ultra-wide implant placement affect the 5-year survival and success rates and marginal bone loss (MBL) of ultra-wide implants. Seventy-eight ultra-wide implants that were placed in 71 patients (39 males and 32 females) from 2008 to 2010 were studied. One-way ANOVA analysis was conducted to evaluate the statistical significance of MBL according to the patient's sex, implant site, and diameter. Independent sample t-tests were used to determine the statistical significance of MBL analysis which was used to determine the significance of the 5-year success and survival rates related to the variables. One-way ANOVA was conducted to evaluate the statistical significance of sex, implantation site, diameter, and MBL. Independent sample t-tests were used to evaluate the correlation between implantability and MBL for implantation reasons, while additional surgery, length, and Kaplan-Meier analysis were used to evaluate 5-year survival and success rates. Results: The mean age of patients was 54.2 years with a survival rate of 92.3% and a success rate of 83.3% over a mean 97.8-month period of observation. MBL averaged 0.2 mm after one year of prosthetic function loading and 0.54 mm at the time of final observation. Success rates correlated with primary stability (P=0.045), survival rates correlated with secondary stability (P=0.036), and MBL did not correlate with any variables. Conclusion: Ultra-wide implants can be used to achieve secure initial fixation in the maxillary and mandibular molar regions with poor bone quality or for alternative purposes in cases of previous implant failure.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제12권1호
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• pp.72-81
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• 1990

Because failure of microvascular flap grafting has sometimes been attributed to vascular obstruction in the anastomotic site, this study investigated the healing process after microvascular anastomoses. The healing process of anastomotic sites were observed by the use of the light and the scanning electron microscope after microvascular anastomoses of the right common carotid artery in rats. The experimental animals were sacrificed on the 4th day, 1st, 2nd, 4th and 6th week. Throughout the whole experimental period, arterial patency rate was 78% (11/14). At the early stage, it was possible to recognize histologically disappearance of endothelial cell and rupture of part of the media. Subintimal hyperplasia and the growth of media appeared around the suture line at the 2nd week. Endothelial cell regeneration occurred and the depth of vessel wall was normalized at the 4th week. By the scanning electron microscope, at the early stage, the anastomotic site was covered with many platelets, red blood cells, fibrins and macrophages. At the 4th week, the insertion site of the thread was completely covered with normal endothelial cells which were parallel to longitudinal axis of vessels and complete reendothelialization over the anastomotic site seemed to take about 6th week.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2009년도 춘계 종합학술대회 논문집
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• pp.1200-1204
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• 2009

정보서비스 활동에서 고객과의 관계는 서비스 성패를 좌우하는 중요한 요소 중 하나이다. 최근에는 웹서비스를 통한 고객관계마케팅활동은 고객과의 관계를 강화하는 데 있어서 그 가능성을 한층 높일 수 있다. 그 중 물리적, 지리적 구애를 받지 않은 서비스의 브랜드 혹은 온라인 공동체의식의 활용은 고객관계 구축의 핵심이 된다. 따라서 본 고에서는 KISTI의 과학향기 서비스의 고객그룹을 대상으로 공동체의식을 형성시킬 수 있도록 서포터즈 운영과 매개효과를 통해 고객그룹 운영 방안을 제시하였다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제16권3호
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• pp.397-418
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• 1994

Microvascular surgery has been widely used in the clinical field of replantation and reconstructive surgery. Since the last 20 years, microsurgical techniques and instruments have been rapidly developed and the success rate is remarkably increased. But thrombotic occlusion of vessels remains the major reason for clinical failure. The change of vessel wall is the most important factor in thrombus formation. If we can reduce the traumatic changes in the vessel walls during surgery, the success rate can be markedly increased. For this study, femoral arteries and veins of 36 Sprague-Dawley rats with average weights of 300gm were used. The author observed the histological changes and healing process in the anastomostic site after 1 hour, 24 hours, 1, 2, 3 and 4 weeks under light microscopy and scanning electron microscopy. The results were as follows : 1. The patency rate was 100% in femoral arteries and 85% in femoral vein. 2. At the early stages after microvascular anastomosis, the loss of endothelial cell in the vessel walls was observed in the wide area including anastomotic site. In scanning electron microscopic finding the anastomotic site was covered with much fibrin, many red blood cells and some platelets. 3. At 1st week, new endothelial cells were formed toward anastomotic site and at 3rd week, the anastomotic site was completely covered by new endothelial cells. At 4th week, the complete endothelialization over the threads was observed. 4. The media extended from the anastomotic site toward the end of the specimen. At later stages, the extent of media necrosis was markedly decreased. But the media necrosis of anastomotic site was not regenerated till 4th week. 5. Intimal hyperplasia appeared at 1st week and increased till 4th week. The layer consisted of endothelialization the most luminal layers and smooth muscle in the deeper layers. But in veins, the response was less pronounced than in arteries. 6. Foreign body granuloma remained during 4 weeks and aneurysm was observed at 3rd week in artery. In aneurismal wall, media necrosis, loss of elastic lamina and intimal hyperplasia were seen.

• 산업경영시스템학회지
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• 제44권4호
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• pp.65-75
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• 2021

This study explores multiple variables of an OTT service for discovering hidden relationship between rating and the other variables of each successful and failed content, respectively. In order to extract key variables that are strongly correlated to the rating across the contents, this work analyzes 170 Netflix original dramas and 419 movies. These contents are classified as success and failure by using the rating site IMDb, respectively. The correlation between the contents, which are classified via rating, and variables such as violence, lewdness and running time are analyzed to determine whether a certain variable appears or not in each successful and failure content. This study employs a regression analysis to discover correlations across the variables as a main analysis method. Since the correlation between independent variables should be low, check multicollinearity and select the variable. Cook's distance is used to detect and remove outliers. To improve the accuracy of the model, a variable selection based on AIC(Akaike Information Criterion) is performed. Finally, the basic assumptions of regression analysis are identified by residual diagnosis and Dubin Watson test. According to the whole analysis process, it is concluded that the more director awards exist and the less immatatable tend to be successful in movies. On the contrary, lower fear tend to be failure in movies. In case of dramas, there are close correlations between failure dramas and lower violence, higher fear, higher drugs.

• 한국지반공학회논문집
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• 제25권10호
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• pp.5-15
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• 2009

본 논문에서는 옥천 및 창녕지역에서 총 24회 수행한 암반앵커 현장인발시험의 결과를 나타내었다. 시험앵커의 정착깊이는 1~6m로 서로다른 암반내에 설치하였다. 앵커의 대부분은 고강도 이형철근인 SD40-D51mm를 사용함으로써 다른 파괴가 일어나기 전에 암반파괴가 먼저 일어나도록 유도하여 암반의 인발저항력을 파악하고자 하였으며, 일부에서는 SD40-D32mm앵커를 설치하여 앵커의 파괴도 아울러 살펴보았다. 많은 시험에서 파괴는 항복에 이르는 극한하중까지 관찰할 수 있었으며, 암반파괴형상은 암반이 들어올려지면서 방사상으로 균열이 발달하는 형태를 나타내었다. 또한 시멘트그라우트와 텐던사이의 부착강도를 평가하고자 방식쉬이스가 설치된 앵커에 대해 실내실험을 실시하였다. 실험결과 텐던-그라우트 사이의 부착강도는 그라우트 일축압축강도의 18~25%로 나타났으며, 방식쉬이스에 의한 부착력 감소는 무시할 수 있을 정도로 작게 나타났다.