• 제목/요약/키워드: HAL

검색결과 266건 처리시간 0.035초

Electrochemical Properties of $LiM_xFe_{1_x}PO_4$ Cathode Materials By Solid-state Reaction

  • Wang, Wan-Lin;Park, Kyung-Hee;Gil, Hal-Bon;Park, Bok-Kee
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
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    • pp.212-212
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    • 2010
  • Recently, lithium transition metal phosphates with an ordered olivine-type structure, $LiMPO_4$ (M=Fe, Mn, Ni, and Co), have attracted extensive attention due to a high theoretical specific capacity (170 mAh/g). The $LiMPO_4$ is the most attractive because of its high stability, low cost, high compatibility with environment. However, it is difficult to attain its full capacity because its electronic conductivity is very low, and diffusion of Li-ion in the olivine structure is slow and the supervalue cation doping was used. In this research, we are used the supervalue cation doping methode such as Cu, Ti, and Mg were partially replace the Fe. The cycling performance resulted of the used $LiM_xFe_{1_x}PO_4$ cathode materials for lithium batteries exhibit excellent high capacity than $LiFePO_4$/Li cells.

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$TiO_2$ 광전극의 광산란 특성을 이용한 염료감응형 태양전지 (Light Scattering Effect Based Silica in Dye-sensitized $TiO_2$ Photovoltaic Cells)

  • ;;;박경희;구할본;박복기
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
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    • pp.213-213
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    • 2010
  • In this thesis, we studied to increased to solar conversion efficiency of DSSC (dye-sensitized solar cell) using nanocrystalline $TiO_2$ semiconductor. We are preparation of $TiO_2$ photoelectrode, assembly the DSSC and put a focus in analyses electrochemical properties of DSSC and using Silica powder in $TiO_2$ photoelectrode for increase light scattering effect and improved conversion efficiency. It attempt to investigate the morphology of the photoelectrode and photovoltaic effects using field emission scanning electron microscopy (FE-SEM) and photovoltaic properties under illumination with AM 1.5 simulated sunlight. We got 146 % enhanced power conversion efficiency when the optimal content of quartz glass powder was 5 wt.% than that another content.

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염료감응형 태양전지용 $TiO_2$ 광전극의 전기화학적 특성 ($TiO_2$ Photoanode on Dye-Sensitized and Electrochemical Properties of Solar Cells)

  • 김은미;박경희;구할본;박복기
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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    • pp.253-254
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    • 2008
  • The $TiO_2$ Pastes was prepared with the starting materials of $TiO_2$ (P-25), ethyl cellulose, a-terpineol and bis(2-ethylhexyl) phthalate, and this $TiO_2$ paste application for dye-sensitized solar cells (DSSCs) were investigated. In order to improved transparency of $TiO_2$ photoanode films, $TiO_2$ paste was changed ethyl cellulose and a-terpineol contents. The morphology of prepared $TiO_2$ films were investigated by field emission scanning electron microscopy (FE-SEM). The electrochemical properties of the thin films and the performance of DSSCs were measured by photovoltaic-current density and AC impedance. Energy conversion efficiency was obtained about 5.7% at ethyl cellulose and a-terpineol on best mixed ratio under illumination with AM 1.5 ($100mWcm^{-2}$)simulated sunlight.

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RTOS기반 LinuxCNC에서 EtherCAT 통신이 적용된 3축 CNC 제어 시스템 개발 (Development of RTOS Based LinuxCNC 3-axis Control System with EhterCAT Communication)

  • 강유수;유경석;태병희;최인휴;이정완;서영호;김병희
    • 산업기술연구
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    • 제40권1호
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    • pp.19-23
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    • 2020
  • In this paper, we proposed a PC-based CNC control system using EtherCAT-based servo drive and I/O device. The default communication of LinuxCNC is a parallel port, and data processing with high bandwidth is impossible. However, it is possible to apply various bandwidth devices through the application of EtherCAT, one of the industrial Ethernet communications with high bandwidth. Therefore, the hardware control method of LinuxCNC was applied through EtherCAT communication from the existing parallel port. Finally, through HAL configuration, I/O device operation check and 3-axis motion control proved the LinuxCNC system with EtherCAT.

졸겔법에 의한 DSSC 광전극의 전기화학적 특성 (Electrochemical Characteristics of TiO2 Photoelectrode for DSSC Prepared by Sol-gel Method)

  • 박아름;;구할본
    • 한국전기전자재료학회논문지
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    • 제25권4호
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    • pp.315-320
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    • 2012
  • In general, a photoelectrode in DSSC(dye sensitized solar cell) are fabricated by using the $TiO_2$ (Titanium dioxide) to realize high efficiency and the efficiency of DSSC is affected by the size, the shape and the property of $TiO_2$. We synthesized the crystalline $TiO_2$ by sol-gel method. In spite of many merits, only weakness for the sol-gel method is taking many process times. To solve this problem, we reduced the fabricating processes. The reduced process is the making process that is $TiO_2$ sol to $TiO_2$ powder with including of two heat treatment and two mixing. We could simplify the process by preparing $TiO_2$ sol to $TiO_2$ paste directly. As a result, DSSC fabrication process is simplified and we have obtained the efficiency best result 3.88% with $V_{OC}$=0.71 V, $J_{SC}=8.70\;mA/cm^{-2}$, and FF=62.37%, respectively.

수열합성한 TiO2 분말을 이용한 염료감응형 태양전지의 전기화학적 특성 (Electrochemical Properties of Dye-sensitized Solar Cells Using the TiO2 Prepared by Hydrothermal Reaction)

  • 나병희;;구할본
    • 한국전기전자재료학회논문지
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    • 제27권1호
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    • pp.33-38
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    • 2014
  • In this work, according to temperature and time of hydrothermal synthesis, the electrochemical properties of $TiO_2$ particle using TTIP based on changing temperature and time in the hydrothermal synthesis were analyzed and optimized temperature and time were derived. When hydrothermal synthesis temperature and time were $200^{\circ}C$ and 1 h, respectively. The fabricated DSSC delivered the best electrochemical properties. In that case, $TiO_2$ particle size was 13.08 nm, electron transport time was $2.34{\times}10^{-3}s$ and recombination time was $4.01{\times}10^{-2}s$. The lowest impedance of $13.52{\Omega}$ and Voc, Jsc, FF is 0.70 V, $1.50mAcm^{-2}$, 65.62%, respectively and corresponding efficiency of 5.34% was considered as the optimal.

Human Papillomavirus Vaccination Acceptability among Female University Students in South Africa

  • Hoque, Muhammad Ehsanul;Ghuman, Shanaz;Van Hal, Guido
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권8호
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    • pp.4865-4869
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    • 2013
  • Background: The objectives of this present study were to assess the awareness of cervical cancer and its risk factors among female undergraduates in South Africa, and to determine the their level of acceptability of Human Papillomavirus (HPV) vaccination. Materials and Methods: This cross-sectional study was conducted in March 2013 among 440 full time undergraduate female students. Results: Of those students who never had sex (n=163), 96 (58.9%) had ever heard of cervical cancer and only 12 students (12.5%) knew that HPV causes cervical cancer. More than a third (35.4%) of the students correctly said that sexual intercourse before age of 18 years is a risk factor for cervical cancer and 55.2% of the students knew about the Pap smear test which is used for screening cervical cancer. The majority (77.3%) were willing to accept HPV vaccination. Results revealed that students who knew about the Pap smear test, and were aware that having multiple sex partners, sexual intercourse before the age of 18 years, smoking and having contracted any STDs are risk factors for cervical cancer were more likely to accept HPV vaccination compared to other groups. Conclusions: The general knowledge of South African female university students about cervical cancer is not sufficient but they have positive attitudes toward getting vaccinated with the HPV vaccine.

열영상 광학계용 비구면 렌즈 제작 (Manufacture of Aspheric Lens Using Thermal Image Optics)

  • 김대중;구할본;김상석;김정호
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.1
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    • pp.191-194
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    • 2003
  • Through using aspheric lens can result in advantages such as an improved optical transfer function, a reduced distortion path or the realization of special image field curvatures. Using the diamond turning method for generating aspherics, the company claim to be able to generate surfaces with a form error of less than $0.33\;{\mu}\;m$ and a surface roughness of less than $0.025\;{\mu}\;m$. In this paper, we are manufacturing thermal image aspheric lens. Thermal image system is electro-optical imaging device which can make visible the difference of infrared energy naturally emitted by objected. In the result of aspherical surface, the form accuracy of about $0.24\;{\mu}\;m$ P-V was obtained and the surface roughness Ra $0.004\;{\mu}\;m$. Also, a brief review of Ultra-precision system Korea photonics technology institute(KOPTI) is present in this paper.

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$Li_{2}O-P_{2}O_{5}-Bi_{2}O_{3}-V_{2}O_{5}$ 유리의 결정화와 전기화학적 특성 변화 (Electrochemical properties and crystallization of $Li_{2}O-P_{2}O_{5}-Bi_{2}O_{3}-V_{2}O_{5}$ Glass)

  • 손명모;이헌수;구할본;김윤선
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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    • pp.550-553
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    • 2001
  • $Li_{2}O-P_{2}O_{5}-Bi_{2}O_{3}-V_{2}O_{5}$ glass containing glass former, $P_{2}O_{5}$ and $Bi_{2}O_{3}$ was prepard by melting the glass batch in pt. erucible followed by guenching on the copper plate. We found that $Li_{2}O-P_{2}O_{5}-Bi_{2}O_{3}-V_{2}O_{5}$ glass-ceramics obtained from the crystallization of glass showed signifieantly higher capacity and longer cycle life tham $LiV_{3}O_{8}$ made from powder synthesis. In this paper, we described crystallization process and $LiV_{3}O_{8}$ crystal growth in glass matrix by increasing temperature. The electrochemical properties were strongly affected by $LiV_{3}O_{8}$ crystal growth in matrix

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리튬 폴리머 전지용 $LiMnO_2$의 합성조건에 따른 충방전 특성 (Charge/discharge Properties As a Function of Synthetic Conditions of $LiMnO_2$ for Lithium Polymer Batteries)

  • 조영재;김종욱;박계춘;위성동;구할본
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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    • pp.541-544
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    • 2001
  • Orthorhombic $LiMnO_2$ was synthesized by solid-state reaction using $LiOH{\cdot}H_{2}O$ and $Mn_{2}O_{3}$ as starting material. Its electrochemical properties as cathode in lithium batteries were examined. X-ray diiffraction revealed that the $LiMnO_2$ compound showed a well-defined orthorhombic phase of a space group with Pmnm. The capacity of $LiMnO_2$ agreed well with its specific surface area and grinding treatment was effective in improving cycling performance. For lithium polymer battery applications. the $LiMnO_2$ cell was characterized electrochemically by charge-discharge experiments. And the relationship between the characteristics of powder and electrochemical properties was studied in this research. A maximum discharge capacity of $160-170mAhg^{-1}$ for $LiMnO_2/Li$ cell was achieved.

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