• Title/Summary/Keyword: Exposure Device

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모바일 장치에서 OTP 기반의 바이오 인식 보안을 위한 프레임워크 (A Framework for Biometric Security based on OTP in Mobile Devices)

  • 한승진
    • 한국컴퓨터정보학회논문지
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    • 제17권4호
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    • pp.121-127
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    • 2012
  • 바이오 인식 기술은 기존의 PIN이나 패스워드와 달리 분실하거나 도용될 가능성이 적기 때문에 PIN이나 패스워드를 대체할 새로운 수단으로 대두되고 있다. 그러나 바이오 인식은 PIN이나 패스워드와 달리 노출되어 도용이 된다면 수정할 방법이 없다. 따라서, 바이오 인식 정보를 이용한 OTP를 모바일 장치에 적용함으로써 기존의 PIN이나 패스워드 혹은 바이오 인식 정보만을 이용한 인증의 문제점을 해결하고자 한다. 본 논문에서는 모바일 장치에서 바이오 인식 정보를 OTP로 사용하여 바이오 인식 정보를 안전하게 서버(TTP)로 전달하는 프레임워크를 제안하고, 기존의 방법과 보안 및 성능을 비교한다.

Effect of Hydrophilic-Lipophilic Balance of Drugs on Their Release Behavior from Amphiphilic Matrix

  • Yoo, Young-Tai;Shin, Hyun-Woo;Nam, Byung-Guk
    • Macromolecular Research
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    • 제11권4호
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    • pp.283-290
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    • 2003
  • Organic drugs including aspirin, omeprazole, and naproxen with three different levels of octanol/water partition coefficient were examined for their release behavior from the amphiphilic PCL-b-PEO-b-PCL (PCEC) matrix. Scanning electron micrograph (SEM) of PCEC illustrated a well defined two-phase morphology consisted of dispersed poly(ethylene oxide) (PEO) domain and continuous polycaprolactone (PCL) phase. Differential scanning calorimetry (DSC) and X-ray diffractometry (XRD) experiments veri tied that three model drugs are dissolved as a molecular dispersion in PCEC matrix. The release of hydrophilic aspirin closely followed the water absorption profile of the matrix indicating that its major fraction is present in PEO domain. However, substantial amount of aspirin present in less hydrophilic region displayed discontinuous biphasic release pattern. In the case of omeprazole with intermediate hydrophobicity consistent release behavior was observed for a period of 24 hrs after the rapid liberation of ca. 10% of the drug presumably partitioned in PEO phase. It was ascribed to the fact that the progressive hydration of PCEC matrix gradually increased the chance of drug/water exposure to compensate the exhaustion of device. Naproxen with the highest octanol/water distribution coefficient among three model drugs exhibited a limited release of 35% for 24 hrs. Finally, hydroxypropyl methylcellulose phthalate (HPMCP)/PCEC blend matrix demonstrated an accelerated and quantitative release of hydrophobic naproxen by generating high porosity and thereby expanding polymer/water interface.

(Ga,Al)이 도핑된 ZnO를 투명전극으로 가진 Cu(In,Ga)Se2 태양전지에 수분이 미치는 영향 (Effect of Moisture on Cu(In,Ga)Se2 Solar Cell with (Ga,Al) Co-doped ZnO as Window Layer)

  • 양소현;배진아;송유진;전찬욱
    • Current Photovoltaic Research
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    • 제5권4호
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    • pp.135-139
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    • 2017
  • We fabricated two different transparent conducting oxide thin films of ZnO doped with Ga ($Ga_2O_3$ 0.9 wt%) as well as Al ($Al_2O_3$ 2.1 wt%) (GAZO) and ZnO doped only with Al ($Al_2O_3$ 3 wt%) (AZO). It was investigated how it affects the moisture resistance of the transparent electrode. In addition, $Cu(In,Ga)Se_2$ thin film solar cells with two transparent oxides as front electrodes were fabricated, and the correlation between humidity resistance of transparent electrodes and device performance of solar cells was examined. When both transparent electrodes were exposed to high temperature distilled water, they showed a rapid increase in sheet resistance and a decrease in the fill factor of the solar cell. However, AZO showed a drastic decrease in efficiency at the beginning of exposure, while GAZO showed that the deterioration of efficiency occurred over a long period of time and that the long term moisture resistance of GAZO was better.

물질수지를 이용한 실내공기질 개선정도 평가 (Evaluation Method for Improvement of Indoor Air Quality Using Mass Balance)

  • 김영희;김문현;양원호
    • 한국환경과학회지
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    • 제15권10호
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    • pp.913-918
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    • 2006
  • Despite the wide distribution of air pollutants, the concentrations of indoor air pollutants may be the dominant risk factor in personal exposure due to the fact that most people spend an average of 80% of their time in enclosed buildings. Researches for improvement of indoor air quality have been developed such as installation of air cleaning device, ventilation system, titanium dioxide$(TiO_2)$ coating and so on. However, it is difficult to evaluate the magnitude of improvement of indoor air quality in field study because indoor air quality can be affected by source generation, outdoor air level, ventilation, decay by reaction, temperature, humidity, mixing condition and so on. In this study, evaluation of reduction of formaldehyde and nitrogen dioxide emission rate in indoor environments by $TiO_2$ coating material was carried out using mass balance model in indoor environment. we proposed the evaluation method of magnitude of improvement in indoor air quality, considering outdoor level and ventilation. Since simple indoor concentration measurements could not properly evaluate the indoor air quality, outdoor level and ventilation should be considered when evaluate the indoor net quality.

On-Line Electric Vehicle의 EMF 저감을 위한 FCCL 차폐효과 분석 (An Analysis of FCCL Shielding Effect for EMF Attenuation to On-Line Electric Vehicle)

  • 심형욱;김종우;조동호
    • 전기학회논문지
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    • 제63권6호
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    • pp.770-775
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    • 2014
  • According to ICNIRP guidelines for limiting exposure to time-varying electric, magnetic and electromagnetic fields up to 300GHz, magnetic flux density which range from 3Hz to 150kHz are regulated to lower than $6.25{\mu}T$. In order to comply with its standard, OLEV(On-Line Electric Vehicle) have been designed considering EMF(Electro-Magnetic Field) reduction. However, if a current flowing in power line would be bigger for increasing power transfer efficiency, the established shield system no longer acts their role properly. In this paper, therefore, FCCL(Flexible Copper Clad Laminate) is applied to power line and pick-up devices to solve the problems. Though, the FCCL is normally utilized to insulator on circuit board, because of its high heat resistance characteristic, flexibility and thin properties, it makes effectiveness in the shielding device as well. 4 types of FCCL shielding structure are introduced to power line and pick-up devices. From the results, the FCCL which are placed in proposed positions shows maximum EMF reduction compared to the established shielding structure. Henceforth, if OLEV is applied FCCL shielding structure in practice, it will not only be more safe but also step forward to commercialization near future.

PECVD 방법으로 제조된 비정질 Si 박막의 RTP를 이용한 결정화 연구 (Use of a Rapid Thermal Process Technique to study on the crystallization of amorphous Si films fabricated by PECVD)

  • 심찬호;김하나;김성준;김정우;권정열;이헌용
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 C
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    • pp.2052-2054
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    • 2005
  • TFT-LCD requires to use poly silicon for High resolution and High integration. Thin film make of Poly silicon on the excimer laser-induced crystallization of PECVD(plasma-enhanced chemical vapor deposition)-grown amorphous silicon. In the thin film hydrogen affects to a device performance from bad elements like eruption, void and etc. So dehydrogenation prior to laser exposure was necessary. In this study, use RTP(Rapid Thermal Process) at various temperature from $670^{\circ}C$ to $750^{\circ}C$ and fabricate poly-silicon. it propose optimized RTP window to compare grain size to use poly silicon's SEM pictures and crystallization to analyze Raman curved lines.

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광학 필터를 사용한 고해상 고체침지 렌즈 기반 근접장 현미경 적용 가능성에 대한 연구 (Feasibility study on realization of high resolution solid immersion lensbased near-field microscopy by use of an annular aperture)

  • 문형배;윤용중;김태섭;박영필;박노철;박경수
    • 정보저장시스템학회논문집
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    • 제6권2호
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    • pp.79-82
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    • 2010
  • In optical imaging systems, such as microscopes, high resolution exposure systems, and optical storage devices, higher optical resolution is a requirement. One of the promising technologies that is able to satisfy this requirement with relatively simple construction and reliable performance are, solid immersion lens (SIL)-based near-field (NF) optical systems. High NA optical systems using annular apertures have been investigated as one solution to achieve higher resolutions and an extended focal depth. By applying an optimized annular aperture to convention SIL optical head resolution can be increased by approximately 20%. This novel SIL-based near-field optics will be verified through experiments such as measuring focused beam spot profiles and observing the topology of a measurement sample. The studied SIL-based near-field optics can be applicable to not only next generation optical storage device but also high resolution microscopy and pattering technologies.

전파정류방식의 고전압발생장치를 이용한 X선 기기의 특성 평가 (Characteristic Analysis of X-ray Device using the High Voltage Generator on Full-wave Rectification Method)

  • 김영표;김태곤;이호식;박용필;천민우
    • 한국전기전자재료학회논문지
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    • 제22권6호
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    • pp.516-521
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    • 2009
  • X-ray system which is usefully used in diagnosis of the patient, being bombed of radioactivity is a big weak point when irradiates a X-ray to the human body so that ICRP restricted the radiation exposure tolerance of the human body. In order to reduce being bombed, the many research and development is now advanced. A lots of diagnostic X-ray machines have currently used due to the increase of occurrence efficiency of X-ray and precisely the output control by using the inverter which is a high speed switching semiconductors. For getting the confidence of the X-ray machine, the same radiation occurrence, same evaluation, and same irradiation condition are necessary when evaluates X-ray irradiation. It is the most important part for the accuracy of the test result and the patient safety. This research has produced the high voltage occurrence system of full-wave rectification method by using the LC resonance inverter, and evaluated the irradiation reproducibility in order to use it in diagnosis of the patient.

Detection of PspA by Interdigitated Nanogap Devices

  • Park, Jimin;Park, Dae Keun;Lee, Cho Yeon;Kang, Aeyeon;Oh, Jihye;Kim, Gyuhee;Lee, Sangho;Yun, Wan Soo
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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    • pp.268.2-268.2
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    • 2013
  • Nanogap interdigitated electrodes (NIDEs) can serve as an alternative platform for the biomolecular detection [1]. In this work, the NIDEs were adopted in a simple and sensitive detection of Pneumococcal surface protein A (PspA). The NIDEs were fabricated by the combination of photo and chemical lithography. Photolithographically-defined initial gap of about 200 nm was narrowed down to a few tens of nanometers by surface-initiated growth of the initial electrodes (chemical lithography) [2]. Bare silicon oxide surface between the electrodes was chemically modified to immobilize capturing antibodies and, after exposure to the samples, the device was immersed in a solution containing the probe-antibody-conjugated Au nanoparticles (Au NPs). The conductance change accompanied with the Au NP immobilization was interpreted as the existence of PspA. Detection limit of the measurements and further improvement of the detection efficiency were discussed with the results from I-V analysis, scanning electron microscopy, and atomic force microscopy.

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모바일 환경에서 다중 바이오인식 기반의 금융 거래를 위한 사용자 인증 프레임워크 (A Framework of User Authentication for Financial Transaction based Multi-Biometrics in Mobile Environments)

  • 한승진
    • 한국컴퓨터정보학회논문지
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    • 제20권1호
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    • pp.143-151
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    • 2015
  • 바이오인식 기술은 기존의 PIN이나 패스워드와 달리 분실하거나 도용될 가능성이 적기 때문에 새로운 인증 수단으로 대체되고 있다. 그러나 바이오인식 정보는 PIN이나 패스워드 혹은 개인정보와 달리 노출되어 도용이 된다면 수정할 방법이 없다. 따라서, 기존의 단일 모달리티에 단일 바이오인식 정보처럼 노출이 되면 치명적인 방법이 아닌 다중 모달리티와 다중 바이오인식 정보를 사용하여 사용자와 TTP 혹은 금융기관 간 인증하도록 함으로써 본 논문은 보다 신뢰성있는 방법을 제안하고 기존의 방법과 보안 및 성능을 비교한다.