• Title/Summary/Keyword: current trace

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Adsorptive Stripping Voltammetry of Indium-Morin Complex (Indium-Morin 착물에 관한 흡착벗김전압전류법적 연구)

  • Se Chul Sohn;Tae Yoon Eom;Yeong Kyeong Ha;Ki-Suk Jung
    • Journal of the Korean Chemical Society
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    • v.35 no.5
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    • pp.506-511
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    • 1991
  • A sensitive adsorptive stripping voltammetric study was investigated on the complex of indium with morin at a hanging mercury drop electrode in 0.1 M acetate buffer (pH 3.20) solution. The adsorption phenomena were observed by differential-pulse voltammetry. The effects of various analytical conditions were discussed on the reduction peak current of the adsorbed complex on the surface of HMDE. Interferences by other trace metals and surfactant were also discussed. Detection limit was 2.6 nM of indium after 90 second deposition time, and the relative standard deviation (n = 7) at 4TEX>${\mu}g$/l indium was 2.0%.

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EFFICIENT USN MIDDLEWARE FOR ASSET TRACKING

  • Kim, Kwang-Soo;Kim, Min-Soo;Jo, Jung-Hee;Pyo, Cheol-Sig;Park, Shin-Young
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.361-364
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    • 2007
  • A small sized device with computing, communicating, sensing capability is changing our life. It will be deployed in the world and acquire a lot of data from the world. It is used for various applications such as military surveillance, environmental monitoring, structure health monitoring, building management, asset tracking, etc. In this paper we focus on USN middleware for asset tracking. A mobile asset is moving here and there within a specific area. The USN middleware tracks the mobile assets in real-time by using sensor nodes and notify their current positions to a user. To achieve the goal, the USN middleware provides some features related to the positions of mobile assets.. They are storing location data by using 3D indexing method, retrieving them by using spatio-temporal query, making trace of an asset, and retrieving the history data of an asset. In the paper, we developed USN middleware to adapt the requirements of asset tracking. It can help users increase the efficiency of their business related to mobile assets and make a valuable decision.

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Effects of Cement Alkalinity on the Time-to-Corrosion of Reinforcing Steel in Concrete under Chloride Exposure

  • Nam, Jingak;Hartt, William H.;Kim, Kijoon
    • Corrosion Science and Technology
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    • v.3 no.6
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    • pp.245-250
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    • 2004
  • A series of classical G109 type concrete specimens was exposed to cyclic wet and dry ponding with 15 w/o NaCl solution for approximately five years. Mix design variables included 1) three cement alkalinities (EqA of 0.97, 0.52, and 0.36) and 2) three water-cement ratios (0.50, 0.41, and 0.37). To determine the corrosion initiation time, corrosion potential and macro-cell current between top and bottom bars were monitored. Subsequent to corrosion initiation, specimens were autopsied and visually inspected. Concrete powder samples were collected from top rebar trace and chloride concentration was measured. Also, time-to-corrosion, $T_i$, for specimens of the individual mix designs was represented using Weibull analysis. Time-to-corrosion was a distributed parameter; and because of this, corrosion initiation of four identical specimens for each mix varied, often over a relatively wide range. Specimens fabricated using the lowest water cement ratio and the highest alkalinity cement exhibited the longest time-to-corrosion initiation and the highest chloride threshold levels. Time-to-corrosion did not increase monotonically with cement alkalinity, however, presumably as a consequence of relatively high $Cl^-$ binding in the lower pore water pH range. The chloride threshold level, $Cl_{th}$, increased with increasing $T_i$ and, consequently, was greatest for the highest cement alkalinity specimens.

Universities in India's National System of Innovation: An Overview

  • Krishna, Venni V.
    • Asian Journal of Innovation and Policy
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    • v.1 no.1
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    • pp.1-30
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    • 2012
  • The status and functioning of Indian universities is explored in the Indian context from an NSI perspective. Whilst NSI is the main guiding post, the very social and economic context of Indian situation reflect the theoretical underpinning of this paper. The First part serves as a background to knowledge institutions and university sector in India. Basically, it identifies the main actors and agencies of India's NSI, namely, public research system comprising national laboratories, main science and technology agencies and councils and the university system. Given the focus of the paper on Indian universities in a macro historical perspective, the Second part is devoted to trace the growth and structure of university sector in terms of three phases, namely, 1940s to 1980; 1980 to 1990; and the era of liberalization after 1991. The Third part of the paper is devoted to knowledge production and knowledge diffusion. There are some important findings coming out of the quantitative data. It is argued that Indian production of doctorates is falling behind countries like China. Further, Indian universities are yet to achieve Humboltian goal. Finally, the paper has a concluding section which concerns with the current and future challenges facing Indian universities and their role in India's NIS.

Design of a Fresnel Lens for a Solar End-pumped Solid-state Laser

  • Ou, Mingyu;Hu, Pian;Lan, Lanling;Liu, Yan;Zhou, Jun;Shi, Xiaotao
    • Current Optics and Photonics
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    • v.4 no.5
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    • pp.441-445
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    • 2020
  • A novel design for a Fresnel lens for a solar end-pumped laser is demonstrated in this paper. The new hybrid Fresnel lens includes two parts, inner and outer. The inner part is a twice-total-internal-reflection and vertical-transmission lens. The outer part is a once-total-reflection and vertical-transmission lens. The radius of the Fresnel lens is 600 mm, and its focal length is 750 mm. The concentrating performance of the Fresnel lens is examined using TracePro. The results show that the concentration efficiency has been greatly improved. The total concentration efficiency of the hybrid Fresnel lens reaches 73.2% when the radius of the laser rod is 3 mm. This design can simplify the concentration system of a solar end-pumped solid-state laser.

Unconstrained e-Book Control Program by Detecting Facial Characteristic Point and Tracking in Real-time (얼굴의 특이점 검출 및 실시간 추적을 이용한 e-Book 제어)

  • Kim, Hyun-Woo;Park, Joo-Yong;Lee, Jeong-Jick;Yoon, Young-Ro
    • Journal of Biomedical Engineering Research
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    • v.35 no.2
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    • pp.14-18
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    • 2014
  • This study is about e-Book program based on human-computer interaction(HCI) system for physically handicapped person. By acquiring background knowledge of HCI, we know that if we use vision-based interface we can replace current computer input devices by extracting any characteristic point and tracing it. We decided betweeneyes as a characteristic point by analyzing facial input image using webcam. But because of three-dimensional structure of glasses, the person who is wearing glasses wasn't suitable for tracing between-eyes. So we changed characteristic point to the bridge of the nose after detecting between-eyes. By using this technique, we could trace rotation of head in real-time regardless of glasses. To test this program's usefulness, we conducted an experiment to analyze the test result on actual application. Consequently, we got 96.5% rate of success for controlling e-Book under proper condition by analyzing the test result of 20 subjects.

EMI Prediction of Slew-Rate Controlled I/O Buffers by Full-Wave and Circuit Co-Simulation

  • Kim, Namkyoung;Hwang, Jisoo;Kim, SoYoung
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.14 no.4
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    • pp.471-477
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    • 2014
  • In this paper, a modeling and co-simulation methodology is proposed to predict the radiated electromagnetic interference (EMI) from on-chip switching I/O buffers. The output waveforms of I/O buffers are simulated including the on-chip I/O buffer circuit and the RC extracted on-chip interconnect netlist, package, and printed circuit board (PCB). In order to accurately estimate the EMI, a full-wave 3D simulation is performed including the measurement environment. The simulation results are compared with near-field electromagnetic scan results and far-field measurements from an anechoic chamber, and the sources of emission peaks were analyzed. For accurate far-field EMI simulation, PCB power trace models considering IC switching current paths and external power cable models must be considered for accurate EMI prediction. With the proposed EMI simulation model and flow, the electromagnetic compatibility can be tested even before the IC is fabricated.

Bismuth Coated Carbon Fiber Microelectrode with Gallic Acid n-Propyl Ester for Trace Copper Analysis (비스무스코팅 탄소섬유전극과 갤릭산 착물을 사용한 구리 이온의 흔적량 분석)

  • Ly, Suw-Young;Lee, Chang-Hyun;Jung, Young-Sam
    • Journal of Environmental Science International
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    • v.16 no.10
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    • pp.1111-1118
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    • 2007
  • A bismuth-coated carbon fiber microelectrode was prepared using cyclic voltammetry (CV). An analytical application was performed for the copper analysis with Square Wave Stripping Voltammetry (SWSV). Gallic acid n-propyl ester (PG) was used for the complex formation with a copper ion, and electrochemical measurements were performed with a pre-amplifier of a low-current module for nano am per detection. The effects of various parameters on the response were optimized. Analytical working ranges of $0.03-25.9\;{\mu}gl^{-1}$ and $0-25\'mgl^{-1}$ Cu(II) were obtained. The relative standard deviation at $13\;mgl^{-1}$ Cu was 0.9% (n = 12) in optimum conditions. The detection limit was found to have been $0.019\;{\mu}gl^{-1}$, with a 30-sec accumulation time. The developed methods were applied to a copper assay in water samples.

Fabrication and Properties of MFISFET Using $LiNbO_3$ Ferroelectric Films ($LiNbO_3$ 강유전체를 이용한 MFISFET의 제작 및 특성)

  • Jung, Soon-Won;Koo, Kyung-Wan
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.57 no.2
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    • pp.135-139
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    • 2008
  • MFISFETs with platinum electrode on the $LiNbO_3$/aluminum nitride/Si(100) structures were successfully fabricated and the properties of the FETs have been discussed. $I_D-V_G$ characteristics of MFISFETs for linear region (that is, 0.1 V of the drain voltage) showed hysteresis loop with a counter-clockwise trace due to the ferroelectric nature of $LiNbO_3$ films. A memory window (i.e., threshold voltage shift) of the fabricated device was about 2[V] for a sweep from -4 to +4[V]. The estimated field-effect electron mobility and transconductance on a linear region were 530[$cm^2/V{\cdot}s$] and 0.16[mS/mm], respectively. The drain current of 27[${\mu}A$] on the "on" state was more than 3 orders of magnitude larger than that of 30[nA] on the "off" state at the same "read" gate voltage of l.5[V], which means the memory operation of the MFISFET.

A Study on the Scribing of FTO using Pulsed Nd:YAG Laser (펄스형 Nd:YAG 레이저를 이용한 FTO 식각에 대한 연구)

  • Kim, Hee-Je;Park, Sung-Joon;Son, Min-Kyu;Lee, Dong-Kil;Lee, Kyoung-Jun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.57 no.8
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    • pp.1407-1411
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    • 2008
  • In material processing, a laser system with optimal laser parameters has been considered to be significant. Especially, the laser scribing technology is thought to be very important for fabricating DSSC(Dye sensitized solar eel!) modules with good quality. Moreover, the $TEM_{00}$ mode laser beam is the most dominant factor to decide the IPCE(Incident photon to current conversion efficiency) characteristics. In order to get the $TEM_{00}$ mode, a pin-hole is inserted within a simple pulsed Nd:YAG laser resonator. And the spatial field distribution is measured by using three size pin-hole diameters of 2.0, 6.0mm respectively. At that moment, each case has the same laser beam energy by adjusting the discharge voltage and pps(pulse per second). From those results, it is known that the pin-hole size of 2.0mm has the perfect $TEM_{00}$ mode. In addition, at the charging voltage of 1000V, 10pps and the feeding speed of 1.11mm/sec, the SEM photo of FTO(Fluorine-doped tin oxide) thin film layers shows the best scribing trace.