• Title/Summary/Keyword: 방사선 경화

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A Comparative Study on Structural Performance of Wind Turbine Composite Blades with Room-Temperature and Radiation Curing (상온 및 방사선 경화 복합재 풍력 블레이드의 구조성능 비교)

  • Jeon, Jae Heung;Kim, Sung Jun;Shin, Eui Sup
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.25 no.3
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    • pp.203-209
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    • 2012
  • In this paper, cross-sectional stiffnesses, static stresses, and dynamic natural frequencies are analyzed to examine the structural performance of wind turbine composite blades. The material properties of composite materials are based on room-temperature and radiation curing processes. The cross-sectional stiffnesses of composite blades are calculated by applying a beam theory with solid-profile cross sections. The wind turbine blades are modeled with a finite element program, and static analyses are carried out to check the maximum displacement and stress of the blades. In addition, dynamic analyses are performed to predict the rotating natural frequencies of the composite blades including the effects of centrifugal force. By comparing these analysis results, mainly owing to the material properties of composite materials, an improvement in the structural performance of the blades according to the curing process is investigated.

Long-term Follow-up of Metaphyseal Sclerotic Lines in Children Treated with Pamidronate (파미드로네이트 치료받은 환자에서 발생한 골간단 경화성 선에 대한 장기간 추적 연구)

  • Choi, Yu-Mi;Suh, Jin-Soon;Cho, Byoung-Soo
    • Childhood Kidney Diseases
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    • v.18 no.2
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    • pp.92-97
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    • 2014
  • Purpose: Bisphosphonates are widely used for the management steroid-induced osteoporosis (SIO) in children. With the increasing use of bisphosphonates, there have been reports of abnormal radiological findings in the growing skeleton. Therefore, their use in pediatric patients remains controversial. The present study was conducted to evaluate the long-term follow-up radiographic features, particularly metaphyseal sclerotic lines, in children who receive pamidronate therapy for nephropathy. Methods: Twenty-four children with nephropathy treated with oral calcium and pamidronate (mean duration, 9 months; dose, 100 mg daily), were evaluated retrospectively. All patients had SIO secondary to chronic glucocorticoid therapy for treating nephropathy. Long bone radiographic imaging was performed before treatment with pamidronate, and at follow-up, several years later. Physeal growth rates were estimated by measuring the distance that the sclerotic lines moved on the radiographs during the corresponding time intervals. Results: The mean follow-up period was 138 months. Long bone radiographs showed well-defined sclerotic lines at the metaphyseal ends, progressively moving from the physeal plate to the diaphysis, in all patients. The mean rate of movement of the sclerotic line was 6.21 mm per year. In 12 patients, the lines disappeared. The mean rate of growth in height was 7.33 cm per year. Conclusions: Results of long-term follow-up suggest that the metaphyseal sclerotic lines associated with pamidronate treatment tend to disappear without affecting overall skeletal growth. Bisphosphonate treatment for SIO in children with nephropathy seems to be safe, although further studies in larger number of patients are needed.

프린팅 월드 1-미국의 UV인쇄

  • Jo, Gap-Jun
    • 프린팅코리아
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    • s.24
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    • pp.152-157
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    • 2004
  • 미국의 매엽 전문 이노새사들이 양질의 품질로 보담하는 UV인쇄에 매료되는 데는 많은 이유가 있다. 먼저, UV인쇄에 사용되는 공식 잉크들은 경화되거나 장기 보존처리를 위해 인쇄물 표면이 UV방사선에 노출되는 결과를 통해 시각적으로는 고광택을 발휘하며 이 외에도 은은한 코팅, 빛나는 색깔, 살아있는 섬세함, 심지어 현재 인기가 오르고 있는 비코팅 매엽 인쇄물까지 잘 표현하고 있다. 물론 여기에는 잉크가 즉시 경화된다는 사실이 전해진다.

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Physical properties of novel composite using Portland cement for retro-filling material (치근단 역충전용 포틀랜드 시멘트 신복합재료의 물리적 성질 고찰)

  • Lee, Sang-Jin;Cho, Ok-In;Yum, Ji-Wan;Park, Jeong-Kil;Hur, Bock;Kim, Hyeon-Cheol
    • Restorative Dentistry and Endodontics
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    • v.35 no.6
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    • pp.445-452
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    • 2010
  • Objectives: The aim of this study was to compare apical sealing ability and physical properties of MTA, MTA - AH-plus mixture (AMTA) and experimental Portland cement - Epoxy resin mixture (EPPC) for a development of a novel retro-filling material. Materials and Methods: Forty-nine extracted roots were instrumented and filled with gutta-percha. Apical root was resected at 3 mm and the retro-filling cavity was prepared for 3 mm depth. Roots were randomly divided into 3 groups of 15 roots each. The retro-filling was done using MTA, AMTA, and EPPC as the groups divided. Four roots were used as control groups. After setting in humid condition for 24 hours, the roots were immersed in 1% methylene blue dye solution for 72 hours to test the apical leakage. After immersion, the roots were vertically sectioned and photos were taken to evaluate microleakage. Setting times were measured with Vicat apparatus and digital radiographs were taken to evaluate aluminum equivalent thickness using aluminum step wedge. The results of microleakage and setting time were compared between groups using one-way ANOVA and Scheffe's post-hoc comparison at the significance level of 95%. Results: AMTA and EPPC showed less microleakage than MTA group (p < 0.05). AMTA showed the highest radio-opacity than other groups and the novel EPPC showed 5 mm aluminum thickness radio-opacity. EPPC showed the shortest initial and final setting times than other groups while the MTA showed the longest (p < 0.05). Conclusions: Under the condition of this study, the novel composite using Portland cement-Epoxy resin mixture may useful for retro-filling with the properties of favorable leakage resistance, radio-opacity and short setting time.

Analyzation of Correlation between Clinical Factors and Carotid Ultrasonography Diagnosis (경동맥 초음파진단과 관련된 임상변수에 대한 분석)

  • Cho, Jin-Young;Ye, Soo-Young
    • Journal of the Korean Society of Radiology
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    • v.14 no.5
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    • pp.705-713
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    • 2020
  • Arteriosclerosis is a disease in which blood circulation is impaired due to loss of elasticity as blood vessels become narrower, and is a potential cause of recently increasing cardiovascular and cerebrovascular diseases. Carotid ultrasound is used as a predictor of cardiovascular and cerebrovascular diseases by evaluating the degree of atherosclerosis. Therefore, this paper attempted to investigate the correlation between the increase in the thickness of the inner media and various clinical variables in carotid ultrasound. Patients with carotid ultrasound findings were classified into three stages: mild intima thickening, sclerosis, and significant stenosis. CAVI (Carotid Ankle Vascular Index: vascular age) data measured in the degree and physical characteristics of the carotid artery(gender, age, body mass index, blood pressure), blood test(total cholesterol, triglycerides, high-density lipoprotein, low-density lipoprotein, creatine phosphokinase, fasting blood sugar), and arteriosclerosis test were collected. It was confirmed that the carotid intima thickness was correlated with variables such as hypertension, hyperlipidemia, and BMI, and also correlated with the risk factors of cardiovascular disease as CAVI increased.

Liposclerosing Myxofibrous Tumor - A case report - (지방경화성 점액섬유종(Liposclerosing myxofibrous tumor) - 1예 보고 -)

  • Yoo, Chang-Young;Jung, Eun-Sun;Park, Gyeong-Sin;Lee, Youn-Soo;Jee, Won-Hee;Kang, Chang-Suk;Lee, Kyo-Young
    • The Journal of the Korean bone and joint tumor society
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    • v.12 no.2
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    • pp.126-130
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    • 2006
  • Liposclerosing myxofibrous tumor (LSMFT) is a fibro-osseous lesion of the bone with a marked predilection for the intertrochanteric region of the proximal femur. It is characterized by a complex mixture of histological elements including fibrous dysplasia-like features, myxofibrous tissue, lipomatous area, ischemic ossification, xanthoma cells and pseudo-Paget's bone. Though some consider LSMFT as a variant of the fibrous dysplasia, intraosseous lipoma, or other benign osseous lesions, recently LSMFT is emerged as a genuine clinicopathologic entity. We experienced a 48-year female patient with typical histologic and radiologic findings of LSMFT. It was located at the intertrochanteric area of the femur. Radiologically, the lesion was radiolucent and ground-glass appearance with sclerotic rim in the plain film and magnetic resonance imaging. Histologically, myxofibrous tissue, lipomatous area and fibrous dysplasia-like features were predominant findings.

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Hypertrophic Osteodystrophy in a Dog (비대섬 골이형성증의 진단 영상)

  • 최지혜;조태현;김현욱;박성민;최민철;윤정희
    • Journal of Veterinary Clinics
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    • v.17 no.2
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    • pp.490-494
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    • 2000
  • 2달령의 수컷 로트와 일러가 4일간 설사와 통증.보행 실조 등의 증상을 보여 (주)해 마루 소동물 임상 의자 연구소에 의뢰되었다 흉부 방사선 검사에서 폐야 전반에 걸친 페포성 침윤과 흉벽의 심란 비후가 관찰되어 흉막폐렴으로 진단하였으며 복강 초음파 검사에서 상 복부에서 소량의 복수가 관찰되었고 전반적인 간 echogenicity가 증가되어 있었다. 치료 후 설사 증상은 사라지고 전신 상태가 다소 호전되어 내원 후 7일째에 흉부 방사선 검사를 재 실시하였다. 흉막과 폐의 병변은 변화가 없었으나 상완골과 요골의 골간단 부분에 이상 소견 이 발견되어 골격계 방사선 검사를 실시한 결과 상완골, 요골, 대퇴골 그리고 경골의 골간단에 경화성 변화와 무정형의 골막 반응이 관찰되었고 요골, 척골과 경골의 골간단 부분에 성 장판 외의 방사선 투과성 선이 관찰되었다. 이상의 특이적인 방사선 소견을 바탕으로 비록 본 질환의 정확한 원인은 밝힐 수 없었으나, 감염성 원인에 의한 비대성 골이형성증으로 진단하였다.

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