• 대한기계학회논문집A
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• 제22권2호
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• pp.311-320
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• 1998

The cryogenic fracture behaviors of austenitic stainless steel HN2 developed for nuclear fusion reactor were evaluated quantitatively by using the small punch(SP) test. The electrochemical polarization test was applied to study thermal aging degradation of HN2 steel. The X-ray diffraction(XRD) analysis was conducted to detect carbides and nitrides precipitated on the grain boundary of the heat treated HN2 steel. The mechanical properties of the HN2 steel significantly decreased with increasing time and temperature of heat treatment or with decreasing testing temperature. The integrated charge(Q) obtained from electrochemical polarization test showed a good correlation with the SP energy(ESP) obtained by means of SP tests. From the results observed in the x-ray diffraction and anodic polarization curve, it was known that the material the grain boundary. Combining SP test and electrochemical polarization test, it could be useful tools to non-destructively evaluate the cryogenic fracture behaviors and the aging degradation for cryogenic structural material.

• International Journal of Aeronautical and Space Sciences
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• 제12권2호
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• pp.93-114
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• 2011

The current status of Canadian research on rotor-based actively controlled technologies for helicopters is reviewed in this paper. First, worldwide research in this field is overviewed to put Canadian research into context. Then, the unique hybrid control concept of Carleton University is described, along with its key element, the "stiffness control" concept. Next, the smart hybrid active rotor control system (SHARCS) projected's history and organization is presented, which aims to demonstrate the hybrid control concept in a wind tunnel test campaign. To support the activities of SHARCS, unique computational tools, novel experimental facilities and new know-how had to be developed in Canada, among them the state-of-the-art Carleton Whirl Tower facility or the ability to design and manufacture aeroelastically scaled helicopter rotors for wind tunnel testing. In the second half of the paper, details are provided on the current status of development on the three subsystems of SHARCS, i.e. that of the actively controlled tip, the actively controlled flap and the unique stiffness-control device, the active pitch link.

• 한국지하수토양환경학회지:지하수토양환경
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• 제19권5호
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• pp.18-25
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• 2014

Traditional investigation procedures of soil and groundwater contamination are followed by soil gas sampling, soil sampling, groundwater sampling, establishment of monitoring wells, and groundwater monitoring. It often takes several weeks to obtain the analysis reports, and sometimes, it needs supplemental sampling and analysis to delineate the polluted area. Laser induced fluorescence (LIF) system is designed for the detection of free-phase petroleum pollutants, and it is suitable for on-site real-time site investigation when coupling with a direct push testing tool. Petroleum products always contain polycyclic aromatic hydrocarbon (PAH) compounds possessing fluorescence characteristics that make them detectable through LIF detection. In this study, LIF spectroscopy of 5 major fuel products was conducted to establish the databank of LIF fluorescence characteristic spectra, including gasoline, diesel, jet fuel, marine fuel and low-sulfur fuel. Multivariate statistical tools were also applied to distinguish LIF fluorescence characteristic spectra among the mixtures of selected fuel products. This study successfully demonstrated the feasibility of identifying fuel species based on LIF characteristic fluorescence spectra, also LIF seemed to be uncovered its powerful ability of tracing underground petroleum leakages.

• 정보처리학회논문지C
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• 제14C권4호
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• pp.313-320
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• 2007

본 논문에서는 MS 워드프로세서의 입력 파일에 대한 유효성을 검사하여 MS 워드프로세서의 보안 취약성을 분석하는 방법을 제안하였다. 즉, 워드프로세서에 적용되는 입력 파일의 헤더 정보를 분석함으로써, 그 입력 파일에 존재하는 취약성을 검출하였다. 본 논문에서 수행한 입력 파일 유효성 테스팅은 기존 결함 주입 도구인 Holodeck 및 CANVAS 등으로는 테스트할 수 없다. 제안한 방법은 헤더를 가진 데이터 파일을 입력으로 사용하는 한글, MS 엑셀 등의 입력 파일에 대한 취약성 검출에도 적용될 수 있다. 또한, 대상 소프트웨어들의 결함 허용성 평가 및 신뢰성 평가에도 사용될 수 있다.

• Interdisciplinary Bio Central
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• 제2권2호
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• pp.1.1-1.8
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• 2010

Microdevices have been used as effective experimental tools for the rapid and multiplexed analysis of individual cells in single-cell assays. Technological advances for miniaturizing such systems and the optimization of delicate controls in micron-sized space homing cells have motivated many researchers from diverse fields (e.g., cancer research, stem cell research, therapeutic agent development, etc.) to employ microtools in their scientific research. Microtools allow high-throughput, multiplexed analysis of single cells, and they are not limited by the lack of large samples. These characteristics may significantly benefit the study of immune cells, where the number of cells available for testing is usually limited. In this review, I present an overview of several microtools that are currently available for single-cell analyses in two popular formats: microarrays and microfluidic microdevices. Then, I discuss the potential to study human immunology on the single-cell level, and I highlight several recent examples of immunoassays performed with single-cell microdevice assays. Finally, I discuss the outlook for the development of optimized assay platforms to study human immune cells. The development and application of microdevices for studies on single immune cells presents novel opportunities for the qualitative and quantitative characterization of immune cells and may lead to a comprehensive understanding of fundamental aspects of human immunology.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.2021_2022
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• 2009

Partial discharges(PD) is a important factor to evaluate the insulation state in high voltage electric machinery. However, measuring PD under the circumstances of power plant is occasionally impossible due to the relatively high magnitude of noise which is emanated from the operating machinery. In some case, the instrument measuring PD can not even perform a calibration that initializes tools and enhance the accuracy. This paper presents that we devised a noise reduction method and demonstrated the usefulness in acquiring reliable PD signals. We attached a series of filter and transformer at the input of power source of the instruments which refrains high noise signals from incoming to the instruments. We experimented the efficiency of noise reduction applying the device into the Dangjin Power Plant and Factory. As a result of testing with the filter and transformer, we can easily calibrate the PD signal compared to the case without the device. Additionally, we can detect the small PD signal which was unperceived with a normal device.

• Annals of Clinical Neurophysiology
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• 제10권1호
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• pp.29-32
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• 2008

Although various criteria on the diagnosis of diabetic neuropathy are applied from trial to trial, being tailored in concert with its purpose, the utmost evidences of the diagnosis are subjective symptoms and objective signs of neurologic deficit. The application and interpretation of auxiliary electrophysiological test including nerve conduction study (NCS) should be made on the context of clinical pictures. The evaluation of the functions of small, thinly myelinated or unmyelinated nerve fibers has been increasingly stressed recently with the advent of newer techniques, e.g., measurement of intraepidermal fiber density, quantitative sensory testing, and autonomic function test. And the studies with those techniques have shed light to the nature of the evolution of diabetic neuropathy. The practical application of these techniques to the diagnosis of diabetic neuropathy in the individual patients, however, should be made cautiously due to several shortcomings: limited accessibility, wide overlapping zone between norm and abnormality with resultant unsatisfactory sensitivity and specificity, difficulty in performing subsequent tests, unproven quantitative correlation with clinical deficit, and invasiveness of some technique. NCS, as an extension of clinical examination, is still the most reliable electrophysiological test in evaluating neuropathy and gives the invaluable information about the nature of neuropathy, whereas the newer techniques need more refinement of the procedure and interpretation, and the accumulation of large scaled data of application to be considered as established diagnostic tools of peripheral neuropathy.

• 분석과학
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• 제27권4호
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• pp.196-200
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• 2014

국가 공정서 중 하나인 대한민국약전외의약품 기준에는 디페메린염산염의 정량법으로 유해시약인 아세트산수은을 사용하는 비수적정법이 수재되어 있다. 본 연구에서는 디페메린염산염의 환경 친화적인 대체 시험법으로 보다 안전하고 효율적인 친환경용매인 에탄올을 사용하는 중화적정법을 개발하고, 분석법을 검증하였다. 디페메린염산염의 직선성은 상관계수(r)가 0.999 이상을 나타내었고, 정확도는 99.10~99.71%, 정밀도는 0.64% 이하로 나타났다. 개발된 시험법은 대한민국약전외의약품 기준의 개정에 기여가 될 것이다.

• 한국정보통신학회논문지
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• 제19권3호
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• pp.683-688
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• 2015

최근 소프트웨어의 결함을 탐지할 수 있는 다양한 종류의 동적분석 도구가 점점 더 많이 활용되고 있다. 하지만 업계에서 실제로 발생하는 결함에 대한 조사는 지금까지 거의 없었다. 본 논문에서는 C/C++, 자바 프로그램에서 결함을 찾아내는 툴인 CodeSonar가 찾아낸 결과를 분석하고자 한다. 분석결과 동남권 지역에서 가장 많이 발생하는 결함들을 다양한 방법으로 제시한다.

• 수산해양교육연구
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• 제22권3호
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• pp.402-419
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• 2010

The purposes of this study were to be free from the fixed instruction and help students have confidence in computer education and improve finding a solution voluntarily. The researcher designed the project instruction of UCC to enhance the community spirit through understanding the problems and solving those. The results of this study are as follows. First, learner changed their consideration in social education. They changed positively the thought about computer education: Form It is tedious and a memoriter subject.' to 'It's fun and good to do by ourselves. Second, students interested in UCC and doing it more actively. Especially, they enhanced the skill of using informations in both on and off-line and community spirit through helping each team members. This shows possibility and availability in not only social studying but also various adaption in other subjects. The researcher provides it would be better if this developed model should be practiced in school and examined the effectiveness in other aspects. lastly in other to examine its validity of enhancing problem-solving and effectiveness of interaction in community, the standard questionnaire and testing tools will be developed in the future.