• Asian Pacific Journal of Cancer Prevention
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• 제13권9호
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• pp.4281-4284
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• 2012

Background: Osteosarcoma is the most common bone cancer in children, responsible for a high rate of amputation and death. This is the first long-term, population-based, epidemiologic and survival study in Thailand. Objective: To study the incidence and survival rates of pediatric osteosarcoma in Khon Kaen. Method: Childhood osteosarcoma cases (0-19 years) diagnosed between 1985-2010 were reviewed. The data were retrieved from the population-based data set of the Khon Kaen Cancer Registry and medical records from Srinagarind Hospital, Faculty of Medicine, Khon Kaen University. All cases were censored until the end of April 2012. The age-standardized incidence rate (ASR) was calculated using the standard method. Survival experience was analyzed using the standard survival function (STATA 9.0) and presented with a Kaplan-Meier curve. Results: 58 cases were enrolled. The overall ASR was 14.1 per million. Males and females were equally affected. The peak incidence was for 15-19 year-olds in both sexes (ASR=10.4 per million in males and 8.5 in females). The 5-year overall survival rate was 27.6% (95% CI: 15.8-40.8%). The median survival time was 1.6 years (95% CI: 1.2-2.1). In a subgroup analysis, the patients who received only chemotherapy survived longer (5-year survival 45.7%, median survival time 4.1 years, p=0.12). Conclusion: The incidence rate for childhood osteosarcoma was slightly less than those reported for Western countries. The survival rate was also lower than reports from developed countries. Further evaluation of the treatment protocol and risk factor stratification is needed.

• 한국콘텐츠학회논문지
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• 제20권6호
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• pp.406-414
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• 2020

수출은 해외 신규시장 개척을 가능케 하여 내수시장의 의존성을 줄여주는 역할을 한다. 또한 기업의 전략적 수단으로써 수출은 국가의 성장에 기여할 뿐 아니라 기업의 규모의 경제, 범위의 경제, 경험효과를 최대한 이용할 수 있는 기회를 제공한다. 실제로 내수시장의 성장 한계와 해외 시장에 대한 정보기술의 발달로 많은 기업들이 수출을 통해 해외 시장으로의 진출을 촉진시키고 있다. 본 논문은 대구에 위치한 기업들을 대상으로 산업조직론적 관점과 전략관점에 근거하여 각 변수들이 수출에 미치는 영향에 대해서 분석하였다. 산업조직론적 관점에서의 실증분석 결과를 살펴보면, 제도적 협력과 정부지원이 기업의 수출에 유의적으로 긍정적인 영향을 미치는 것으로 나타났으며, 수출성과에는 제도적 협력만이 긍정적인 영향을 미치고 있음을 알 수 있었다. 전략관점에서는 제품차별화, 해외수출망, 해외진출 국가 수가 수출에 긍정적인 영향을 미치는 것으로 나타났으며, 수출성과에는 해외수출망, 해외진출 국가 수가 긍정적인 영향을 미치는 것으로 나타났다.

• 대한기계학회논문집A
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• 제30권11호
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• pp.1494-1501
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• 2006

Mechanical and physical properties of a copper alloy for a liquid rocket engine(LRE) combustion chamber liner application were tested at various temperatures. All test specimens were heat treated with the condition they might experience during actual fabrication process of the LRE combustion chamber. Physical properties measured include thermal conductivity, specific heat and thermal expansion data. Uniaxial tension tests were preformed to get mechanical properties at several temperatures ranging from room temperature to 600$^{\circ}C$. The result demonstrated that yield stress and ultimate tensile stress of the copper alloy decreases considerably and strain hardening increases as the result of the heat treatment. Since the LRE combustion chamber operates at higher temperature over 400$^{\circ}C$, the copper alloy can exhibit time-dependent behavior. Strain rate, creep and stress relaxation tests were performed to check the time-dependent behavior of the copper alloy. Strain rate tests revealed that strain rate effect is negligible up to 400$^{\circ}C$ while stress-strain curve is changed at 500$^{\circ}C$ as the strain rate is changed. Creep tests were conducted at 250$^{\circ}C$ and 500$^{\circ}C$ and the secondary creep rate was found to be very small at both temperatures implying that creep effect is negligible for the combustion chamber liner because its operating time is quite short.

• 한국융합학회논문지
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• 제9권8호
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• pp.117-125
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• 2018

본 연구에서는 각막굴절수술 후 콘택트렌즈 착용 실태, 유통 중인 콘택트렌즈의 베이스커브와 직경을 조사하여, 변형된 각막에 콘택트렌즈를 착용하였을 때 렌즈 움직임과 착용양상을 확인해보고자 하였다. 각막굴절수술 후 16.5%가 콘택트렌즈를 착용한 경험이 있었다. 또한, 콘택트렌즈의 베이스커브는 8.6 mm, 직경은 14.0 mm가 가장 많은 비중을 차지하였다. 각막굴절수술 한 24안의 각막은 편평하였으며, 콘택트렌즈를 착용했을 때 렌즈는 이측과 하측으로 모두 이동하였다. 각막굴절수술 후 콘택트렌즈 착용으로 불편함을 느낄 수 있어 렌즈 착용시 상세한 설명과 한정적인 렌즈의 종류로 정교한 피팅이 필요하며, 콘택트렌즈의 산업과 임상적인 연구에서 융합이 필요할 것이라고 생각된다.

• 한국지반환경공학회 논문집
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• 제9권7호
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• pp.25-35
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• 2008

국내의 경우 일반적인 2차로 도로터널은 시공경험 및 축적된 제반자료가 풍부하여 표준적인 지보패턴이 제시되고 있으나, 2-Arch 도로터널의 경우 아직 시공경험 및 계측자료가 부족하여 특정지형 및 암질에 대해 별도의 발파설계와 해석을 통해 선정한 지보패턴을 표준적으로 적용하고 있다. 따라서 본 연구에서는 2-Arch 도로터널의 설계 및 시공시 적용되고 있는 표준지보패턴에 대하여 하중분담률 및 편토압에 따른 거동을 분석하고 발파진동이 중앙벽체에 미치는 영향을 분석하여 적용된 지보재의 적정성 여부를 검토하였다. 그 결과 표준지보패턴에 적용되는 지보량은 적정한 것으로 나타났으나, 이는 특정지형 및 암질 조건을 고려하여 해석 후 선정된 것으로, 향후 2-Arch 도로터널의 설계 및 시공시 최종적인 표준지보패턴 선정은 대상 터널의 지형조건, 토질조건, 시공조건 등을 종합적으로 고려하여 결정되어야 할 것으로 사료된다.

• 대한기계학회논문집A
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• 제34권6호
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• pp.757-762
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• 2010

탄소섬유강화 복합재료는 금속재료에 비하여 높은 비강성과 비강도 등의 우수한 기계적 성질을 나타내고 있으며, 이러한 이유로 최근 경량화가 요구되는 항공기용 재료와 자동차용 재료 등으로 그 사용이 급격히 증가하여 금속재를 대체하고 있다. 그러나 대부분의 기계구조물에서는 반복하중에 의한 피로 파손이 주로 발생하고 있다. 그러므로 섬유강화 복합재를 사용한 기계구조물의 내구성을 확보하기 위해서는 이에 대한 피로 해석 및 내구성 평가가 필요하다. 따라서 피로 손상 모델을 이용하여 피로 시험으로부터 구한 손상량을 이용하여 피로손상 누적곡선을 획득하고 해석하였다.

• 복식
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• 제57권3호
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• pp.14-22
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• 2007

This study is about the excavated costume representing fundamental "Conservation and Restoration". It's not a report of a specific case, but it is a guideline that contains the costume and textile of museum collection. It is not research based on experiments; however, this paper is basically consists of various reported-documents. Followings are the conclusions of this study 1. These are the factors that we have to know to prevent the causes of fabric's degradation. -Light, -Humidity and temperature, -Microscopic organism, -Insect and rodent animal, -Air pollution, -Ph, -Handling 2. Basic principles of conservation and restoration follows are: -Select the Reversible method, -Represent the easily distinguishable repaired place, -Should be acted by an expert or people with experience, -Before the restoration, accurate and specified records should be completed, -Procedure, treatment method, and materials used should be recorded prior to restoration, -Should be cared minimally, -Be cautious when using the conservation materials, -When caring, make sure nothing is against the principle of aesthetic, historic, and form of preservation 3. The types of restoration are type of straight or curve, type of hole, type of without warp or weft, type of special part damage something like sleeve, collar, type of form that is severely damaged, and type of separated pieces. 4. The method of restoration is sewing, stitching, and the combination of sewing and stitching. 5. The restoration seams are welt seam, plain seam, flat felled seam, french seam etc. And there are kinds of used-sewing, such as, broad stitching, backstitch, half backstitch, basking, hemming, saddle stitching etc.

• 경영정보학연구
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• 제14권2호
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• pp.93-102
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• 2012

네트워크 패러다임의 변화 속에 새로운 제품, 기술, 서비스와 더불어 비즈니스 모델을 제시하는 기업이 새로운 강자로 부상하고 있다. 기업들은 네트워크가 가져온 시공간의 제약 해결 등을 얻기 위해 기존의 비즈니스를 네트워크 공간으로 옮기기 위한 노력을 진행하였으며, 이러한 과정에서 기업들은 전에 없던 새로운 비즈니스 모델을 출현시키고 있다. 본 연구에서는 비즈니스 모델 변화를 위해서는 고객이 아닌 새로운 네트워크 가입자 개념으로 비즈니스 모델에 대한 재해석이 필요함을 강조한다. 비즈니스에 대한 근본적인 변화 없이 네트워크의 특성만을 이용하고자 하는 기업들은 고객의 니즈를 잃어버리는 구조적 관성에 빠질 수 있다. 하지만, 사례 기업은 고객이 원하는 가치가 무엇인가에 주목하였으며, 이를 통해 고객을 새로운 네트워크 가입자의 개념으로 살펴봄으로써 기존 비즈니스 모델을 새롭게 변화시키고 나아가 기업간 관계 형태를 변화시켰다. 본 연구에서는 사례분석을 통해 네트워크 관점에서 비즈니스 모델의 변화과정 및 가치곡선과 고객경험사이클을 적용하여 이에 따른 성과를 설명함으로써 네트워크 관점에서의 비즈니스 모델에 대한 재해석의 필요성을 제시하였다.

• Physical Therapy Rehabilitation Science
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• 제5권1호
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• pp.1-8
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• 2016

Objective: The present study was to investigate the discrimination capacity of the Performance Oriented Mobility Assessment-Gait Scale (POMA-GS), for predicting falls in stroke survivors. Design: Retrospective cohort study. Methods: Data including the characteristics and number of falls of 52 chronic stroke patients from a rehabilitation center were collected. The number of falls each subject had experienced in the previous year were investigated through interviews. The subjects were divided into two groups depending on the number of falls: if falls occurred twice or more on the basis of the time of study after stroke, they were defined as the falls group and if there was no fall experience or one fall, they were defined as the non-falls group. The subjects were examined with the POMA-GS, and physical functions were examined using by the One Leg Stand Test (OLST), Sit to Stand Test (SST), 10-m Walk Test, Lower Extremity in Fugl-Meyer assessment (FM-LE), and Trunk Impairment Scale (TIS). The validity of POMA-GS for falls prediction was analyzed. Results: In the POMA-GS, which predicts falls in stroke survivors, the cut-off value was 8.5 (sensitivity 72%; specificity 65%) and the area under the curve was 0.75 (95% confidence interval: 0.60-0.90, p<0.007). There was a significant difference in the OLST, SST, FM-LE, and TIS between the subjects with POMA-GS >8.5 and the subjects with POMA-GS ${\leq}8.5$. Conclusions: The POMA-GS could be a useful tool in predicting falls in stroke survivors, as its discrimination capacity and predictive validity is proven satisfactory.

• Journal of Korean Neurosurgical Society
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• 제29권12호
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• pp.1577-1583
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• 2000

Objectives : Among the various types of minimally invasive spine surgeries, thoracoscopic surgery is becoming more widely accepted and increasingly utilized. This report delineates our clinical experience using thoracoscopy to resect herniated thoracic discs in 16 patients who suffered from myelopathy or intolerable radiculopathy. Patients and Methods : Between Mar. 1997 and Sep. 1999, 16 consecutive patients underwent thoracoscopic discectomy for treatment of herniated thoracic discs. There were 12 men and 4 women(mean age 43.5 years ; range 18-61 years). Eleven patients presented with myelopathic signs and symptoms from spinal cord compression and 5 patients had incapacitating thoracic radicular pain without myelopathy. The surgical level was varied between T3 and T12. The pathology of specimen were 11 hard discs and 5 soft discs herniations. Thoracoscopic techniques were performed with long narrow spine instruments and high speed drill through 3 or 4 ports under one lung ventilated general anesthesia. During the operation three patients were converted to open thoracotomy due to intolerable one lung ventilation, excessive bleeding and inadequate operation field. The mean operation time was 264min.(range : 100-420min.), and postoperative mean admission period was 11 days. Results : Clinical and neurological outcomes were good in all patients(mean follow-up period 20 months). Among the eleven myelopathic patients, 8 improved neurologically, and 3 stabilized. Among the five radiculopathic patients, 4 recovered completely and no patient had worsened. Postoperative complications were pleural effusion in one case, intercostal neuralgia in one, delayed hemopneumothorax in one, prolonged air leakage in one and pneumonia in one case. Conclusions : Thoracoscopic discectomy needs a steep learning curve to be familiar to anatomical space and handling of endoscopic instruments. However, it is technically feasible and can be effectively performed with acceptable results.