• 제목/요약/키워드: sensitivity enhancement

검색결과 253건 처리시간 0.029초

Electrochemical Investigation of Bovine Hemoglobin at an Acetylene Black Paste Electrode in the Presence of Sodium Dodecyl Sulfate

  • Zhan, Guoqing;Li, Chunya;Luo, Dengbai
    • Bulletin of the Korean Chemical Society
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    • 제28권10호
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    • pp.1720-1724
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    • 2007
  • Electrochemical behaviors of bovine hemoglobin (Hb) at an acetylene black paste electrode based on the enhancement effect of sodium dodecyl sulfate (SDS) were investigated. In the optimal conditions, a very weak reduction peak was observed at an acetylene black paste electrode for hemoglobin in the absence of SDS. However, the reduction peak current increased remarkably after the addition of 4.0 × 10?4 mol L?1 SDS, suggesting that SDS exhibits obvious enhancement effect to the determination of hemoglobin. All the experimental parameters, such as pH value, concentration of SDS, accumulation time and accumulation potential were optimized for hemoglobin analysis. The proposed method possesses high sensitivity (detection limit is 3.0 × 10?9 mol L?1), wide linearity (6.0 × 10?9 to 6.0 × 10?7 mol L?1), rapid response and low cost. Finally, the method was successfully employed to determine hemoglobin in a spiked sample.

Loss Optimization for Voltage Stability Enhancement Incorporating UPFC Using Particle Swarm Optimization

  • Kowsalya, M.;Ray, K.K.;Kothari, D.P.
    • Journal of Electrical Engineering and Technology
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    • 제4권4호
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    • pp.492-498
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    • 2009
  • The placement of the UPFC is the major concern to ensure the full potential of utilization in the transmission network. Voltage stability enhancement with the optimal placement of UPFC using stability index such as modal analysis, Voltage Phasor method is made and the loss minimization including UPFC is formulated as an optimization problem. This paper proposes particle swarm optimization for the exact real power loss minimization including UPFC. The implementation of loss minimization for the optimal location of UPFC was tested with IEEE-14 and IEEE-57 bus system.

인간 시각의 인지 특성을 이용한 local contrast enhancement (Human Perception Adaptive Local Contrast Enhancement)

  • 방성배;김원하
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송∙미디어공학회 2017년도 추계학술대회
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    • pp.101-103
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    • 2017
  • 본 논문은 human visual system(HVS)에 따른 주파수 민감도와 공간에서 다양한 특성들을 구현하기 위한 신호처리 방법을 개발하였다. 인간의 눈은 주파수 성분에 따라 민감도가 다르며 초점에서 멀수록 인지 가능한 해상도가 떨어진다. 주파수 민감도를 구현하기 위해서 본 논문은 영상 신호의 에너지 스펙트럼 모양이 contrast sensitivity function(CSF)의 모양이 되도록 하여 영상 신호의 에너지를 증가시켰으며 신호 방향에 적응적인 multiband energy scaling 방법을 개발하였다. 기존의 시스템에서 능률만을 향상시키는 기존의 분석 모델과 비교하면 개발한 방법은 HVS에 좀 더 적절하고 선호되게 영상 신호를 처리할 수 있다.

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Recent Trends of Light-enhanced Metal Oxide Gas Sensors: Review

  • Cho, Minkyu;Park, Inkyu
    • 센서학회지
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    • 제25권2호
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    • pp.103-109
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    • 2016
  • Recent light-enhanced metal oxide gas sensors are reviewed in this article. The basic mechanisms of a light-enhanced metal oxide gas sensor are discussed. Many literatures reveal that the standalone sensitivity and the response/recovery time enhancements enabled by the exposing light are not as high as the performance enhancement provided by external heating. Therefore, both optimal amount of external heating and exposed light intensity are necessary to increase the performance of these light-enhanced gas sensors. The development of highly light sensitive materials and structures is important to lower the overall power consumptions of the sensors.

색채 응용 시스템의 색향상을 위한 기호색 보정 (Favorite colar correction for color enhancement in color application system)

  • 이응주;하영호
    • 한국통신학회논문지
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    • 제22권7호
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    • pp.1566-1573
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    • 1997
  • In this paper, we propose a favorite color correction algorithm for color enhancement in color application system which represent preferred colors for viewer's demands. The proposed algorithm corrects skin color which is widely used as a reference color for color control of color application system, blue color which is directly related to tri-stimulus values, and green color which has higher visual sensitivity. In the proposed algorithm, the vaiation range of phase detector output voltage was minimized for the favorite color saturation changes, thus the favorite from the burst signal for the phase detector characteristic, thus the favorite color was easilty detected from the other color without overlapping of correctionranges.

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RMA2/RMA4 모형을 이용한 서낙동간 수문연계운영의 수질개선 효과 예측 (Prediction of Water-Quality Enhancement Effects of Gates Operation in the West-Nakdong River Using RMA2/RMA4 Models)

  • 이금찬;윤영삼;이남주
    • 한국환경과학회지
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    • 제18권9호
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    • pp.971-981
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    • 2009
  • An objective of this study is as follows: 1) performing sensitivity analysis and parameter estimation of RMA2 and RMA4 models for the West-Nakdong River, 2) drawing up alternatives of gates-operation for water-quality enhancement, and 3) quantitative evaluation of methodology of 'flow-restoration by gates-operation' among 'Comprehensive Plan Improving Water-Quality in the West-Nakdong River(WNR)' with the target water-quality(BOD at Nakbon-N point: below 4.3 mg/L). The parameters for the RMA2 (depth-averaged two-dimensional flow model) and RMA4 (depth-averaged two-dimensional water-quality model) were determined by sensitivity analysis. Result of parameter estimation for RMA2 and RMA4 models is $1,000\;Pa{\cdot}s$ of the eddy viscosity, 20 of the Peclet number, 0.025 of the Manning coefficient, and $1.0\;m^2/s$ of the diffusion coefficient. We have evaluated the effects of water-quality enhancement of the selected alternatives by numerical simulation technique with the models under the steady-state flow condition and the time-variant transport condition. Because of no-resuspension from river bottom and considering BOD as conservative matter, these simulation results slightly differ from real phenomena. In the case of $50\;m^3/s$ of Daejeo-gate inflow, two-dimensional flow pn results result represents that small velocity occurs in the Pyungkang Stream and no flow in the Maekdo River. In the WNR, there occurs the most rapid flow near timhae-bridge. In the WNR, changes of water-quality for the four selected simulation cases(6, 10, 30, $50\;m^3/s$ of the Daejeo-gate inflow) were predicted. Since the Daejeo-Gate and the Noksan-Gate can be opened up to 7 days, it would be found that sustainable inflow of $30\;m^3/s$ at the Daejeo-gate makes BOD in the WNR to be under the target of water-quality.

시작 차량의 실내 감성 향상에 관한 연구 (A Study on Enhancement of Human Sensitivity for Interior of Prototype Vehicles)

  • 최재원;양화준;이석희
    • 한국정밀공학회지
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    • 제20권5호
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    • pp.124-131
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    • 2003
  • As the new model development lead time becoming shorter and the market requirements becoming more strict, automobile manufacturer begins to utilize 3-dimensional CAD system based techniques such as DMU (Digital Mock-up), Rf (Rapid Prototyping), VE (Virtual Engineering) to meet the market trends. But, no satisfactory utilities have been developed yet, to represent emotional properties such as embossment on the surface of interior parts, touch originated from material characteristics in virtual environment, so it is inevitable to manufacture prototype parts to verify actual feeling which passengers feel in automobile. This paper suggests a methodology to enhance the human sensitivity via embodying embossment on the surface of prototype car interior trim without deterioration of dimensional accuracy using RIM (Reaction Injection Molding) and thermoforming method.

주파수 민감도와 신호의 방향을 이용한 영상 화질 향상 기법 (Frequency Sensitivity and Signal Direction for Image Enhancement)

  • 방성배;김원하
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 2014년도 추계학술대회
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    • pp.245-247
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    • 2014
  • 본 논문은 human visual system(HVS)에 따른 주파수 민감도와 공간에서 다양한 특성들을 구현하기 위한 신호처리 방법을 개발하였다. 인간의 눈은 주파수 성분에 따라 민감도가 다르며 초점에서 멀수록 인지 가능한 해상도가 떨어진다. 주파수 민감도를 구현하기 위해서 본 논문은 영상 신호의 에너지 스펙트럼 모양이 contrast sensitivity function(CSF)의 모양이 되도록하여 영상 신호의 에너지를 증가시켰으며 신호 방향에 적응적인 multiband energy scaling 방법을 개발하였다. 기존의 시스템에서 능률만을 향상시키는 기존의 분석 모델과 비교하면 개발한 방법은 HVS에 좀 더 적절하고 선호되게 영상 신호를 처리할 수 있다.

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Development of Array-based Technology for Detection of HAV Using Gold-DNA Probes

  • Wan, Zhixiang;Wang, Yefu;Li, Shawn Shun-Cheng;Duan, Lianlian;Zhai, Jianxin
    • BMB Reports
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    • 제38권4호
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    • pp.399-406
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    • 2005
  • A sensitive method for detection of Hepatitis A virus (HAV) by utilizing gold-DNA probe on an array was developed. Amino- modified oligodeoxynucleotides at the 5' position were arrayed on an activated glass surface to function as capture probes. Sandwich hybridization occurred among capture probes, the HAV amplicon, and gold nanoparticle-supported oligonucleotide probes. After a silver enhancement step, signals were detected by a standard flatbed scanner or just by naked eyes. As little as 100 fM of HAV amplicon could be detected on the array. Therefore, the array technology is an alternative to be applied in detection of HAV due to its low-cost and high-sensitivity.

Photo-sensing Characteristics of VO2 Nanowires

  • Sohn, Ahrum;Kim, Eunah;Kim, Haeri;Kim, Dong-Wook
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.197.1-197.1
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    • 2014
  • VO2 has intensively investigated for several decades due to its interesting physical properties, including metal-insulator transition (MIT), thermochromic and thermoelectric properties, near the room temperature. And also gas and photo sensing properties of VO2 nanowires have attracted increasing research interest due to the high sensitivity and multi-sensing capability. We studied the light-induced resistance change of VO2 nanowires. In particular, we have investigated plasmonic enhancement of the photo-sensing properties of the VO2 nanowires. To select proper wavelength, we performed finite-difference time-domain simulations of electric field distribution in the VO2 nanowires attached with Ag nanoparticles. Localized surface plasmon resonance (LSPR) is expected at wavelength of 560 nm. The photo-sensitivity was carefully examined as a function of the sample temperature. In the presentation, we will discuss physical origins of the photo-induced resistance change in VO2.

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