• 제목/요약/키워드: Daegu.Gyeongbuk

검색결과 965건 처리시간 0.033초

Parylene-C 코팅된 의료용 SUS304 소재의 결합력 향상을 위한 플라즈마 처리 효과 (The effect of plasma treatment to improve adhesion strength of parylene-C coated medical grade SUS304)

  • 김동국;송태하;정용훈;강관수;윤덕규;김민욱;우영재;서요한;김경아;노지형
    • 한국표면공학회지
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    • 제55권6호
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    • pp.390-397
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    • 2022
  • Parylene-C which was mainly used for industries such as electronics, machinery and semiconductors has recently been in the spotlight in the medical field due to its properties such as corrosion resistance and biocompatibility. In this study we intend to derive a plan to improve the bonding strength of Parylene-C coating with the SUS304 base material for medical use which can be applied to various medical fields such as needles, micro needles and in vitro diagnostic device sensors. Through plasma pretreatment the bonding strength between Parylene-C and metal materials was improved. It was confirmed that the coated surface was hydrophobic by measuring the contact angle and the improvement of the surface roughness of the sample manufactured through CNC machining was confirmed by measuring the surface roughness with SEM. Through the above results, it is thought that it will be effective in increasing usability and reducing pain in patients by minimizing friction when inserting medical devices and in contact with skin. In addition it can be applied to various application fields such as human implantable stents and catheters, and is expected to improve the performance and lifespan of medical parts.

미세가공 기술 기반의 마이크로니들 어레이 개발 및 패럴린 적용 가능성에 관한 연구 (Research on the Development of Microneedle Arrays Based on Micromachining Technology and the Applicability of Parylene-C)

  • 김동국;윤덕규;이용찬;김민욱;노지형;서요한;강관수;정영훈;김경아;송태하
    • 대한의용생체공학회:의공학회지
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    • 제44권6호
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    • pp.404-413
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    • 2023
  • In this research, we studied the development of a SUS304 microneedle array based on microfabrication technology and the applicability of Parylene-C thin film, a medical polymer material. First of all, four materials commonly used in the field of medical engineering (SUS304, Ti, PMMA, and PEEK) were selected and a 5 ㎛ Parylene-C thin film was deposited. The applicability of Parylene-C coating to each material was confirmed through SEM analysis, contact angle measurement, surface roughness(Ra) measurement, and adhesion test according to ASTM standards for each specimen. Parylene-C thin film was deposited based on chemical vapor deposition (CVD), and a 5 ㎛ Parylene-C deposition process was established through trial and error. Through characteristic experiments to confirm the applicability of Parylene-C, SUS304 material, which is the easiest to apply Parylene-C coating without pretreatment was selected to develop a microneedle array based on CNC micromachining technology. The CNC micromachining process was divided into a total of 5 steps, and a microneedle array consisting of 19 needles with an inner diameter of 200 ㎛, an outer diameter of 400 ㎛, and a height of 1.4 mm was designed and manufactured. Finally, a 5 ㎛ Parylene-C coated microneedle array was developed, which presented future research directions in the field of microneedle-based drug delivery systems.

Effects as Plasma Treatments on CdS Buffer Layers in CIGS Thin Film Solar Cells

  • Jo, Hyun-Jun;Sung, Shi-Joon;Hwang, Dae-Kue;Bae, In-Ho;Kim, Dae-Hwan
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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    • pp.171-171
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    • 2012
  • We have studied the effects of plasma treatments on CdS buffer layers in CIGS thin film solar cells. The CdS layers were deposited on CIGS films by chemical bath deposition (CBD) method. The RF plasma treatments of the CdS thin films were performed with Ar, $O_2 and $N_2 gases, respectively. After plasma treatments, the solar cells with Al:ZnO/i-ZnO/CdS/CIGS structures were fabricated. The surface properties of the CdS/CIGS thin films after plasma treatments were investigated with SEM, EDX and AFM measurements. The electrical properties of manufactured solar cell were discussed with the results of current-voltage measurements. The plasma treatments have a strong influence on the open circuit voltage (VOC) and the fill factor of the solar cells. Finally, a correlation between the surface properties of CdS layer and the efficiencies of the CIGS thin film solar cells is discussed.

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무선 센서네트워크에서 이동성을 지원하는 Tree기반의 Self-Routing 기법 (A Tree based Self-Routing Scheme for Mobility Support in Wireless Sensor Networks)

  • 김영덕;양연모;강원석;김진욱;안진웅
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2008년도 학술대회 논문집 정보 및 제어부문
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    • pp.534-535
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    • 2008
  • 최근 유비쿼터스 기술이 급속도로 발전함에 따라 많은 application들이 다양한 환경에서 통신서비스를 요구하고 있다. 이를 지원하기 위하여 많은 무선 센서 네트워킹 기술들이 제안되었지만 제한된 대역쪽과 높은 에러율로 인하여 이동성을 지원하기에는 부족하였다. 특히, 경로를 획득하기 위한 Route Request (RREQ)의 잦은 브로드캐스트 과정은 오히려 혼잡 및 에너지 소모를 야기시키며 네트워크 성능을 저하시키는 문제점이 있다. 본 논문에서는 언제, 어디서나 다양한 토폴로지 환경에서 자가 구성이 가능하며, 이동성을 지원하는 Tree기반의 Self-Routing 기법을 제안한다. 기존의 센서 네트워크내 멀티홉 라우팅 프로토콜과는 달리, 라우터 혹은 싱크노드의 비컨 프레임내 Association 정보만을 이용하여 새로운 라우팅 테이블을 형성함으로써 컨트롤 패킷의 오버 헤드를 크게 줄일 수 있다. 성능 평가를 위하여 실제 모바일 로봇을 이용한 실험과 시뮬레이션을 동시에 하였으며, 기존의 기법보다 향상된 성능을 가짐을 보인다.

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모바일 환경에서 온톨로지 및 시청각 정보를 이용한 셀프케어 시스템 구현 (An Implementation of Ontology, Vision and Voice Using Self-Care System in Mobile Environment)

  • 권형오;박세권;손종욱;조희섭
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2012년도 한국컴퓨터종합학술대회논문집 Vol.39 No.1(D)
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    • pp.55-57
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    • 2012
  • 최근의 정보통신 기술의 발달은 의료의 중심을 기존의 진단 및 치료에서 예방으로 이동하게 하였다. 이에 따라 환자 뿐 아니라 건강에 관심이 많은 일반인들이 병원 밖에서도 스스로 건강 증진을 위해 질병 예방을 수행할 수 있도록 지원하는 셀프케어 시스템들이 개발되어지고 있다. 그러나 현재 개발되어지고 있는 셀프케어 시스템들은 대부분 회원 등록의 과정이 필수적이며, 또한 회원 등록 과정에서 자가진단을 위해 성별과 같은 기본적인 정보를 수동적으로 입력해야 하는 번거로움이 있다. 따라서 본 논문에서는 사용자의 음성과 영상을 이용한 성별 인식을 통해 비 등록 사용자에 대한 기본정보를 자동으로 인식하고 온톨로지를 이용한 자가진단 서비스에 적용함으로써 회원 등록을 원치 않는 비 등록 사용자에 대한 편의성을 고려하였다. 또한 온톨로지를 이용한 자가진단 서비스의 진단 결과로 질환에 대한 정의 및 증상, 치료 방법을 설명하고 증상의 경중에 따라 방문 치료할 진료과에 대한 정보를 제공함으로써 사용자가 스스로 건강을 진단하고 진단결과에 따라 간단한 치료를 할 수 있으며, 증상의 악화를 예방할 수 있도록 도와준다.

Photocatalytic conversion of CO2 into hydrocarbon fuels with standard titania (Degussa P25) using newly installed experimental setup

  • Kim, Hye Rim;Razzaq, Abdul;Heo, Hyo Jung;In, Su-Il
    • Rapid Communication in Photoscience
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    • 제2권2호
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    • pp.64-66
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    • 2013
  • Photoreduction of $CO_2$ into hydrocarbon fuels on the surface of photocatalyst is one of the breakthroughs in the field of photocatalysis. At present various approaches have been investigated with the aim of increasing the $CO_2$ conversion efficiency. The reactor for photoconversion of $CO_2$ plays a vital role in experimental setup. In this work an attempt was made to testify a newly designed the photoreactor for conversion of $CO_2$ into useful products. The photoreactor was specifically designed for simple operation bearing features of temperature and pressure control. The reactor has been tested successively with the standard titania, Degussa P25 yielding methane with moderate production rate of 30.8 $ppm{\cdot}g^{-1}{\cdot}h^{-1}$ under UV lamp with 365 nm wavelength. The methane yield obtained is comparable to the values reported in literature. Thus we anticipate that this experimental setup equipped with newly designed photoreactor can yield competitive amounts of fuels from $CO_2$ photoredcution via 365 nm UV light illumination on various photocatalysts.

비스-카바졸 유기염료를 이용한 염료감응태양전지 (Organic Sensitizers based on Bis-carbazole for Dye-Sensitized Solar Cells)

  • 김효정;변여진;남정은;김대환;강진규
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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    • pp.397-399
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    • 2012
  • Dye-sensitized solar cells (DSSCs) have received considerable attention as the most promising candidates for renewable energy systems in recent years. Among these, organic dyes which have many advantages such as large absorption coefficients, customized molecular design for desired photophysical and photochemical properties, inexpensiveness and environment-friendliness, are suitable as photosensitizers for DSSCs. We have studied on the design and synthesis of two organic dyes (BECZ 1 and BECZ 2) with a 9-ethyl-9H-carbazole core for dye-sensitized solar cells (DSSCs). Two organic dyes comprised of two 9-ethyl-9H-carbazole moiety as electron-donor, two types of cyanoacrylic acid moiety acting as acceptor. In addition, n-ethyl unit introduced for increasing the solubility and the donating power. The obtained organic dyes were comprehensively characterized by NMR, GC-MS, FAB-MS and UV/Vis spectroscopies. DSSCs sensitized by the dyes BECZ1 and BECZ2 produced ${\eta}$ value 3.31% and a ${\eta}$ value 3.21%.

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휠-트랙 하이브리드 모바일 로봇 플랫폼의 지형 적응성 및 사용자 친화성 향상을 위한 원격 조종기 설계와 개발 (Design and Development of Terrain-adaptive and User-friendly Remote Controller for Wheel-Track Hybrid Mobile Robot Platform)

  • 김윤구;안진웅;곽정환;문전일
    • 제어로봇시스템학회논문지
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    • 제17권6호
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    • pp.558-565
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    • 2011
  • Various robot platforms have been designed and developed to perform given tasks in a hazardous environment for surveillance, reconnaissance, search and rescue, etc. We considered a terrain-adaptive and transformable hybrid robot platform that is equipped with rapid navigation capability on flat floors and good performance in overcoming stairs or obstacles. The navigation mode transition is determined and implemented by adaptive driving mode control of the mobile robot. In order to maximize the usability of wheel-track hybrid robot platform, we propose a terrain-adaptive and user-friendly remote controller and verify the efficiency and performance through its navigation performance experiments in real and test-bed environments.

Serious Blood-Brain Barrier Disruption after Coil Embolization of Unruptured Intracranial Aneurysm : Report of Two Cases and Role of Immediate Postembolization CT Scan

  • Lee, Kyung-Kyu;Kang, Dong-Hun;Kim, Yong-Sun;Park, Jae-Chan
    • Journal of Korean Neurosurgical Society
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    • 제50권1호
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    • pp.45-47
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    • 2011
  • Abnormal contrast enhancement on brain computed tomography (CT) scan after diagnostic or interventional angiography is not rare, and has known to be induced by temporary blood-brain barrier (BBB) disruption from contrast media. Furthermore, it has been regarded as clinically subtle, but reported to have no symptom or mild transient symptoms. However, we recently experienced two cases of serious BBB disruption during the acute period after coiling of an unruptured intracranial aneurysm. One patient presented with an unruptured paraclinoid internal carotid artery (ICA) aneurysm on the right and the other with an unruptured right supraclinoid ICA aneurysm. Both patients showed similar findings on immediate postembolization CT scan and clinical courses after coiling. Typical radiological, clinical characteristics of BBB disruption were described. In addition, the role of immediate postembolization CT scan are also discussed.