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SIMPLE EXTRINSIC FIBER OPTIC METHOD TO EVALUATE ABSORBANCE IN AQUEOUS NANOPARTICLE

  • Hanh, Nguyen Thi Kieu;Kulkarnib, Atul;Kim, T.
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.1723-1726
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    • 2008
  • In recent years, there has been a remarkable progress in the development of the fiber optic sensors for the detection of various chemicals. Fiber optic sensors have the advantages of very small size, flexibility and low cost. The fiber optic sensors employing different optical or spectroscopic phenomena have been reported such as bulk absorption, optical reflectance, fluoresces and energy transfer. In this study, the effect of nanoparticle concentration in liquid upon light absorption and scattering was studied using extrinsic fiber optic method. For the evaluation, we used Red (650 nm) and Blue (430 nm) light sources which are coupled through the standard cuvette using optical fiber to detector. The experiments are carried out with Polystyrene latex (400 - 800 nm), and Silicon (35 - 110 nm) nanoparticles suspended in Isopropanol. Differences in light absorption and scattering depending on nanoparticle concentration and type are discussed. This method may be useful to study nanoparticles properties for various application and research.

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A Study on the Analysis of Field Condition for Ground Fault Protection Installation among Electrical Installations in the Entertainment Area (공연장의 전기설비중 지락보호설비에 대한 현장실태분석 연구)

  • Bae, S.M.;Kim, H.S.;Gil, H.J.;Lee, G.H.
    • Proceedings of the KIEE Conference
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    • 2002.07c
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    • pp.1721-1723
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    • 2002
  • This paper deals with the analysis of field condition for earth leakage current alarming system in the stage lighting, stage sound stage machinery installation. These analyses of field condition were carried out in accordance with investigating an installation of earth leakage current alarming system with respect to a main line of power source, dimmer, sound equipment, machinery mobile unit equipment and so on. As a result of analyses. The earth leakage current alarming system has been installed only a part of the main line of power source and the probability of places which were installed was less than 50(%). Therefore, it is desirable that the earth leakage current alarming system is installed at places which are suitable, for example, dimmer, each kind machinery etc. in order to prevent electrical hazard.

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WRR Cell Scheduling Algorithm Based on BSW (BSW 기반의 WRR 셀 스케쥴링 알고리즘)

  • 조해성;정경택;전병실
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.11A
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    • pp.1717-1723
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    • 2000
  • WRR 셀 멀티프렉싱 알고리즘은 CBR, VBR 트래픽 뿐만 아니라 ABR, UBR 트래픽을 서비스하도록 설계되었다. WRR의구현에 있어 버퍼 관리를 효율적으로 하기 위한 BSW 기법의 알고리즘이제안되었다. 그러나, BSW 방식은 VC 에 실제로 할당된 가중치보다 더 큰 가중치를 할당하고 어느 한 VC의 큐가 비어있게 되면 셀 서비스를 수행하지 못하므로 각 VC의 가중치와 스케줄러의 처리율에 심각한 성능저하를 유발한다. 본 논문에서는 위에서 언급한 BSW 기법의 문제를 해결하기 위해서 셀 지연과 버퍼 이용을 개선한 BSW 구조의 WRR 스케줄링 알고리즘을 제안하였다. 제안된 알고리즘은 기존은 BSW 스케쥴링 알고리즘의 문제점들을 해결하기 위해서 각 VC에 실제로 할당된 가중치를 유지할 수 있도록 하였고, 각 VC의 큐가 비어 있을 경우 다른 VC 셀을 서비스하게 함으로서 평균 셀 지연과 평균 버퍼의 길이를 감소시키고 전체적으로 셀 서비스 율을 높일 수 있다.

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A study on optimal drive waveform and optimal gas mixing ratio of Plasma Display Panel (AC 플라즈마 디스플레이 패널에서의 최적 구동 파형 및 최적 가스 흔합비에 관한 연구)

  • Choi, Hoon-Young;Park, Hun-Gun;Lee, Seok-Hyun
    • Proceedings of the KIEE Conference
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    • 1997.07e
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    • pp.1721-1723
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    • 1997
  • In AC Plasma Display Panel(PDP), serious problems are low radiation brightness and very high discharge voltage. To solve these problems, it is necessary to obtain optimal frequency of drive waveform and optimal gas mixing ratio. This paper presents firing voltage and sustain voltage as frequency of waveform and gas mixing ratio, and proposes optimal frequency of drive waveform and optimal gas mixing ratio.

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Prenconcentration and Determination of Mercury (II) and Methylmercury in Waters by Immobilized 1,5-Diphenylcarbazone and Cold Vapor Atomic Absorption Spectrometry

  • Dadfarnia, Shayessteh;Salmanzadeh, Ali Mohammed;Haji Shabani, Ali Mohammed
    • Bulletin of the Korean Chemical Society
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    • v.23 no.12
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    • pp.1719-1723
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    • 2002
  • 1,5-diphenylcarbazone was immobilized on sodium dodecyl sulfate coated alumina. The alumina particle was effectively used for collection of mercury(II) and methylmercury cations at sub-ppb level. The adsorbed mercury was eluted with l mol $L^{-1}$ of hydrobromic acid solution. The mercury(II) was then directly measured by cold vapor atomic absorption spectrometry utilizing tin (II) chloride where as the total mercury was determined after the oxidation of methylmercury into the inorganic mercury. The methylmercury concentration was calculated by the difference between the value of total mercury and mercury (II). Mercury (II) and methylmercury cations were completely recovered from water with a preconcentration factor of 100 (for 1 L solution.) Relative standard deviation at Hg L ${\mu}gL^{-1}$ level 1.7%(n=8) and the limit of detection was 0.11 ${\mu}gL^{-1}$. The procedure was applied to spring water, well water and seawater and accuracy was assessed through recovery experiments.

Complex Neural Classifiers for Power Quality Data Mining

  • Vidhya, S.;Kamaraj, V.
    • Journal of Electrical Engineering and Technology
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    • v.13 no.4
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    • pp.1715-1723
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    • 2018
  • This work investigates the performance of fully complex- valued radial basis function network(FC-RBF) and complex extreme learning machine (CELM) based neural approaches for classification of power quality disturbances. This work engages the use of S-Transform to extract the features relating to single and combined power quality disturbances. The performance of the classifiers are compared with their real valued counterparts namely extreme learning machine(ELM) and support vector machine(SVM) in terms of convergence and classification ability. The results signify the suitability of complex valued classifiers for power quality disturbance classification.

Power Density Characteristics Analysis and Design of Magnetic Gear according to Speed for Drive Train of 10MW Offshore Wind Turbine (10MW급 해상풍력발전기 드라이브 트레인을 위한 마그네틱 기어의 속도별 설계 및 출력밀도 특성분석)

  • Kim, Chan-Ho;Kim, Yong-Jae
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.64 no.12
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    • pp.1718-1723
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    • 2015
  • The diameter of the rotor of 2MW wind turbine is being developed by a number of companies with more than 80m, reliability and economic efficiency of the wind power generator has been improved. The need for large-scale wind turbine with excellent economy has been attracting attention because the new orders and the location of the wind turbine market has reached a limit. Technology development for enlargement of wind turbine is possible not only the improvement of energy efficiency but also reduce the construction costs per unit capacity. However, mechanical gearboxes used in wind generators have problems of wear, damage, need for lubrication oil and maintenance. Therefore, we want to configure the gearbox of a large-scale wind turbine using a magnetic gear in order to solve these problems of mechanical gearbox.

A Study of Serial Servo Synchronization for Mobile Robot Using Omni-wheel (옴니휠을 가진 모바일 로봇을 위한 시리얼 서보 동기화에 대한 연구)

  • Kim, Dae-Young;Yi, Keon-Young
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.1722-1723
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    • 2007
  • This paper describes a simple method to reduce rotation angle error of mobile robot using omni-wheel[3](omni-bot). This method can be applied to not only omni-bot, but also other robot with a large number of servo motor. Robot using many servo motor as omni-bot is complicated for hardware and software, each servo motor has difficulty in synchronizing. Three servo motor, three omni-wheel and three serial servo motor controller is used, PC or Micro Processor interface with the serial servo controller through "SSC100" protocol. In order to check the improvement of the proposed serial servo synchronization compared to existing sequential communication method. comparing object is rotation angle error of omni-bot. The results of this make building of omni-bot system easy and decrease rotation angle error.

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A Study on Science and Culture Education tapping into Jeju's Special Characteristics for Adults (제주지역 특성을 활용한 성인 과학문화 프로그램에 대한 고찰)

  • Yun, Minhee;Park, Namje
    • Proceedings of the Korea Information Processing Society Conference
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    • 2012.11a
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    • pp.1720-1723
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    • 2012
  • 과학기술,사회(STS, Science and Technology in Society)란 과학과 기술을 역사적이고 사회학적인 시각으로 바라보자는 관점을 뜻한다. 이는 시민들이 이런 시각을 가져야 과학기술과 관련된 사회 쟁점에 대한 올바른 판단이 가능하다는 의미이다. 이를 위해 국가 교육과정체제 이후의 평생교육으로써 성인을 대상으로 하는 과학문화 소통 프로그램이 필요하다. 본 논문은 국내와 해외의 성인 대상의 과학 문화 프로그램을 분석하여 올바른 과학문화 소통을 위한 프로그램 과정은 어떤 모습으로 설계되어야 하는지를 제안한다. 제주대학교 과학기술사회연구센터(STS연구센터)에서 연구하고 있는 제주 특성을 활용한 과학기술문화교육 프로그램을 소개하고, 향후 정보과학 기반의 연구방향도 소개하고자 한다.

Call for emergency action to limit global temperature increases, restore biodiversity, and protect health Wealthy nations must do much more, much faster

  • Atwoli, Lukoye;Baqui, Abdullah H.;Benfield, Thomas;Bosurgi, Raffaella;Godlee, Fiona;Hancocks, Stephen;Horton, Richard;Laybourn-Langton, Laurie;Monteiro, Carlos Augusto;Norman, Ian;Patrick, Kirsten;Praities, Nigel;Rikkert, Marcel GM Olde;Rubin, Eric J.;Sahni, Peush;Smith, Richard;Talley, Nicholas J.;Turale, Sue;Vazquez, Damian
    • Animal Bioscience
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    • v.34 no.11
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    • pp.1723-1726
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    • 2021