• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.140-140
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• 2004

마이크로 기술을 대변하는 Micro-Electro-Mechanical-Systems (MEMS)와 반도체, 각종 micro-sensor 및 actuator 등은 실리콘 위에 박막 코팅한 재료를 주로 사용하고 있다. 따라서 1 Um 이하의 박막코팅에 의해 원하는 성능을 얻으려는 시도가 널리 진행되고 있다 Hard Disk Drive (HDD)의 Head-Disk Interface (HDI)와 MEMS 접촉면에서는 발생하는 마찰 및 마멸에 대한 문제 등은 중요한 고려대상이다. 특히 코팅 층의 표면 파손 현상은 코팅 층의 파손 특성과 코팅 층과 기판 사이의 결합상태가 큰 영향을 미친다.(중략)

• Journal of Veterinary Clinics
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• v.13 no.1
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• pp.77-80
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• 1996

인도의 아메다바드 동물원에서 사육중인 1년생의 수컷 우는 사슴(Muntiacus muntjak)에서 피부사상균증이 발생했다. 발병된 사슴의 얼굴, 머리 및 목 부위 피부에는 모양이 불규칙하고 각피성인 여러개의 회백생 병변을 나타내었다. potassium hydroxide기법에 의해 피부병변에서 Trichophyton verrucosum이 검출되었다. 감염된 피부와 털 시료를 곰팡이 배지에 배양하여 같은 병원체가 검출되었다. 이 사슴과 밀접하게 접촉하였던 사육사에게서는 감염증이 확인되지 않았다. 동물원 동물의 피부염을 감별하는데 있어서 피부사상균을 고려해야 한다는 점이 강조되었다. 저자들의 소견으로는 이것이 인도산 우는 사슴에서 발생한 Trichophyton verrucosum 감염증으로써 최초의 확진된 보고이다.

• Journal of Aerospace System Engineering
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• v.17 no.1
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• pp.51-58
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• 2023

Hypergolic propellants, which can ignite themselves without an ignition source, are difficult to handle due to their corrosiveness and toxicity. Therefore, it is necessary to develop green hypergolic propellants with little or no toxicity. In this study, basic research on green hypergolic ignition propellants was conducted. With 95% hydrogen peroxide as an oxidizer and CNU_HGFv1 as a fuel, ignition and combustion characteristics of propellants were evaluated through a drop test, an ignition test, and a combustion test. As a result of the drop test, the ignition delay time was 9.7 ms. It was 27 ms in the ignition test, which was fast enough to be used as a propellant. As a result of the combustion test, a combustion efficiency of 95.4~98.1% was achieved at about 11.7 bar. It was confirmed that fast and stable combustion was possible without hard start or combustion instability.

• Pediatric Infection and Vaccine
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• v.21 no.3
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• pp.191-198
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• 2014

Purpose: The aim of this study was to evaluate the clinical manifestations, contact history, and status of tuberculosis contact investigations in school-age children and adolescents with pulmonary tuberculosis (TB) at two centers. Methods: This study was conducted with 54 patients in the age ranging from 10 to 18 years, who were diagnosed with pulmonary TB at the Pusan National University Hospital and Pusan National University Children's Hospital, January 2008 to December 2012. We retrospectively reviewed the medical records of the patients. Results: The median age of the patients was 16 years old; 11 patients were aged 10 to 14 and 43 patients were aged 15 to 18. Among 54 patients, 19 had history of contact with pulmonary TB, 10 had contact with house members (household), and remaining 9 had contact with classmates (non-household). One out of 10 patients who had household contacts and 6 out of 9 patients who had non-household contacts were evaluated with contact investigation after the exposure to pulmonary TB. Among 7 patients who were evaluated with contact investigation, 3 were diagnosed with active pulmonary TB, 1 had latent tuberculosis infection (LTBI), and 3 had no evidence of TB or LTBI. The median period of diagnosis after the exposure to active pulmonary TB was 2 years in patients with household contacts and 0.23 years in patients with non-household contacts. Conclusion: This study suggested that if the contact investigation conducted properly, it would be helpful for early diagnosis and prevention of pulmonary TB.

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.3
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• pp.214-221
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• 2011

Purpose: To date most of finite element analysis assumed the presence of 100% contact between bone and implant, which is inconsistent with clinical reality. In human retrieval study bone-implant contact (BIC) ratio ranged from 20 to 80%. The objective of this study was to explore the influence of bone-implant contact pattern on bone of the interface using nonlinear 3-dimensional finite element analysis. Materials and methods: A computer tomography-based finite element models with two types of implant (Mark III Br${\aa}$nemark$^{(R)}$, Inplant$^{(R)}$) which placed in the maxillary 2nd premolar area were constructed. Two different degrees of bone-implant contact ratio (40, 70%) each implant design were simulated. 5 finite element models were constructed each bone-implant contact ratio and implant design, and sum of models was 40. The position of bone-implant contact was determined according to random shuffle method. Elements of bone-implant contact in group W (wholly randomized osseointegration) was randomly selected in terms of total implant length including cortical and cancellous bone, while ones in group S (segmentally randomized osseointegration) was randomly selected each 0.75 mm vertically and horizontally. Results: Maximum von Mises strain between group W and group S was not significantly different regardless of bone-implant contact ratio and implant design (P=.939). Peak von Mises strain of 40% BIC was significantly lower than one of 70% BIC (P=.007). There was no significant difference between Mark III Br${\aa}$nemark$^{(R)}$ and Inplant$^{(R)}$ in 40% BIC, while average of peak von Mises strain for Inplant$^{(R)}$ was significantly lower ($4886{\pm}1034\;{\mu}m/m$) compared with MK III Br${\aa}$nemark$^{(R)}$ ($7134{\pm}1232\;{\mu}m/m$) in BIC 70% (P<.0001). Conclusion: Assuming bone-implant contact in finite element method, whether the contact elements in bone were wholly randomly or segmentally randomly selected using random shuffle method, both methods could be effective to be no significant difference regardless of sample size.

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.05a
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• pp.114-114
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• 2002

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.05a
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• pp.113-113
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• 2002

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.977-978
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• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.1461-1462
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• 2010

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.1047-1048
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• 2010