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Electrochemical Properties of Li1.1V0.75W0.075Mo0.075O2/Graphite Composite Anodes for Lithium-ion Batteries

  • Kim, Hyung-Sun;Kim, Sang-Ok;Kim, Yong-Tae;Jung, Ji-Kwon;Na, Byung-Ki;Lee, Joong-Kee
    • Bulletin of the Korean Chemical Society
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    • v.33 no.1
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    • pp.65-68
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    • 2012
  • Novel type $Li_{1.1}V_{0.9-2x}W_xMo_xO_2$ powders were prepared by a solid-state reaction of $Li_2CO_3$, $V_2O_3$, $WO_2$ and $MoO_2$ precursors in a nitrogen atmosphere containing 10 mol % hydrogen gas, and assessed as anode materials in lithium-ion batteries. The specific charge and discharge capacities of the $Li_{1.1}V_{0.9-2x}W_xMo_xO_2$ anodes were higher than those of the bare $Li_{1.1}V_{0.9}O_2$ anode. The cyclic efficiency of these anodes was approximately 73.3% at the first cycle, regardless of the presence of W and Mo doping. The composite anode, which was composed of $Li_{1.1}V_{0.75}W_{0.075}Mo_{0.075}O_2$ (20 wt %) and natural graphite (80 wt %), demonstrated reasonable specific capacity, high cyclic efficiency, and good cycling performance, even at high rates without capacity fading.

Designing an Efficient and Secure Credit Card-based Payment System with Web Services Based on the ANSI X9.59-2006

  • Cheong, Chi Po;Fong, Simon;Lei, Pouwan;Chatwin, Chris;Young, Rupert
    • Journal of Information Processing Systems
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    • v.8 no.3
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    • pp.495-520
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    • 2012
  • A secure Electronic Payment System (EPS) is essential for the booming online shopping market. A successful EPS supports the transfer of electronic money and sensitive information with security, accuracy, and integrity between the seller and buyer over the Internet. SET, CyberCash, Paypal, and iKP are the most popular Credit Card-Based EPSs (CCBEPSs). Some CCBEPSs only use SSL to provide a secure communication channel. Hence, they only prevent "Man in the Middle" fraud but do not protect the sensitive cardholder information such as the credit card number from being passed onto the merchant, who may be unscrupulous. Other CCBEPSs use complex mechanisms such as cryptography, certificate authorities, etc. to fulfill the security schemes. However, factors such as ease of use for the cardholder and the implementation costs for each party are frequently overlooked. In this paper, we propose a Web service based new payment system, based on ANSI X9.59-2006 with extra features added on top of this standard. X9.59 is an Account Based Digital Signature (ABDS) and consumer-oriented payment system. It utilizes the existing financial network and financial messages to complete the payment process. However, there are a number of limitations in this standard. This research provides a solution to solve the limitations of X9.59 by adding a merchant authentication feature during the payment cycle without any addenda records to be added in the existing financial messages. We have conducted performance testing on the proposed system via a comparison with SET and X9.59 using simulation to analyze their levels of performance and security.

CLASSIFICATION OF CLIFFORD ALGEBRAS OF FREE QUADRATIC SPACES OVER FULL RINGS

  • Kim, Jae-Gyeom
    • Bulletin of the Korean Mathematical Society
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    • v.22 no.1
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    • pp.11-15
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    • 1985
  • Manddelberg [9] has shown that a Clifford algebra of a free quadratic space over an arbitrary semi-local ring R in Brawer-Wall group BW(R) is determined by its rank, determinant, and Hasse invariant. In this paper, we prove a corresponding result when R is a full ring.Throughout this paper, unless otherwise specified, we assume that R is a commutative ring having 2 a unit. A quadratic space (V, B, .phi.) over R is a finitely generated projective R-module V with a symmetric bilinear mapping B: V*V.rarw.R which is non-degenerate (i.e., the natural mapping V.rarw.Ho $m_{R}$(V,R) induced by B is an isomorphism), and with a quadratic mapping .phi.: V.rarw.R such that B(x,y)=1/2(.phi.(x+y)-.phi.(x)-.phi.(y)) and .phi.(rx) = $r^{2}$.phi.(x) for all x, y in V and r in R. We denote the group of multiplicative units of R by U9R). If (V, B, .phi.) is a free rank n quadratic space over R with an orthogonal basis { $x_{1}$,.., $x_{n}$}, we will write < $a_{1}$,.., $a_{n}$> for (V, B, .phi.) where the $a_{i}$=.phi.( $x_{i}$) are in U(R), and denote the space by the table [ $a_{ij}$ ] where $a_{ij}$ =B( $x_{i}$, $x_{j}$). In the case n=2 and B( $x_{1}$, $x_{2}$)=1/2 we reserve the notation [a $a_{11}$, $a_{22}$] for the space. A commutative ring R having 2 a unit is called full [10] if for every triple $a_{1}$, $a_{2}$, $a_{3}$ of elements in R with ( $a_{1}$, $a_{2}$, $a_{3}$)=R, there is an element w in R such that $a_{1}$+ $a_{2}$w+ $a_{3}$ $w^{2}$=unit.TEX>=unit.t.t.t.

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Microwave Dielectric Properties of $[(Pb_{1-x}Ba_{x})_{1/2}La_{1/2}](Mg_{1/2}Nb_{1/2})O_{3}$ Ceramics ($[(Pb_{1-x}Ba_{x})_{1/2}La_{1/2}](Mg_{1/2}Nb_{1/2})O_{3}$의 마이크로파 유전 특성)

  • Lee, Sang-Wook;Nam, Hyo-Duk;Park, Jae-Sung;Seo, Jung-Chul;Kim, Jong-Chul
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11b
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    • pp.476-479
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    • 2001
  • The microwave dielectric properties of $[(Pb_{1-x}Ba_{x})_{1/2}La_{1/2}](Mg_{1/2}Nb_{1/2})O_{3}$ ceramics were investigated. When $[(Pb_{0.9}Ba_{0.1})_{1/2}La_{1/2}](Mg_{1/2}Nb_{1/2})O_{3}$ ceramics were sintered at $1250^{\circ}C$ and $1350^{\circ}C$ for 2hr, the microwave dielectric properties were obtained $\varepsilon_{r}=64\sim80$, $Q{\times}f=11,800\sim18,000$. As a result, $[(Pb_{0.9}Ba_{0.1})_{1/2}La_{1/2}](Mg_{1/2}Nb_{1/2})O_{3}$ having $\varepsilon_{r}=80$, $Q{\times}f=11,800$ (at 4 GHz) was developed.

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Microwave Dielectric Properties of [($Pb_{1-x}Ba_{x}$)$_{1/2}La_{1/2}$]($Mg_{1/2}Nb_{1/2}$)$O_3$ Ceramics ([($Pb_{1-x}Ba_{x}$)$_{1/2}La_{1/2}$($Mg_{1/2}Nb_{1/2}$)$O_3$의 마이크로파 유전 특성)

  • 이상욱;남효덕;박재성;서정철;김종철
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11a
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    • pp.476-479
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    • 2001
  • The microwave dielectric properties of [(Pb$_{1-x}$ Ba$_{x}$)$_{1}$2/La$_{1}$2/](Mg$_{1}$2/Nb$_{1}$2/)O$_3$ ceramics were investigated. When [(Pb$_{0.9}$Ba$_{0.1}$)$_{1}$2/La$_{1}$2/](Mg$_{1}$2/Nb$_{1}$2/)O$_3$ ceramics were sintered at 125$0^{\circ}C$ and 135$0^{\circ}C$ for 2hr, the microwave dielectric properties were obtained $\varepsilon$$_{r}$=64~80, Qxf=11,800~18,000. As a result, [(Pb$_{0.9}$Ba$_{0.1}$)$_{1}$2/La$_{1}$2/](Mg$_{1}$2/Nb$_{1}$2/)O$_3$ having $\varepsilon$$_{r}$=80, Qxf=11,800 (at 4 GHz) was developed.ed.eveloped.ed.

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Survey on Online Continuing Education Requirements according to Practical Experience of Nurses at Small and Medium Sized Hospitals (중소병원 간호사의 실무 경험에 따른 온라인 보수교육 요구도 조사)

  • Eun, Young;Kang, Han Sol;Jeon, Mi Yang
    • Journal of muscle and joint health
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    • v.23 no.3
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    • pp.197-205
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    • 2016
  • Purpose: The purpose of this study was to conduct a comparison analysis on requirements of online continuing education requirements according to practical experience of nurses at small and medium-sized hospitals. Methods: Data had been collected with 236 nurses from May to June, 2015. The data were analyzed with the use of SPSS. Results: Among them, 45.8% participated in online continuing education. Nurses in beginning level required musculoskeletal diseases (20.9%), care for injuries and stomas (5.8%), and surgical disease and operation care (4.7%). Competent nurses required musculoskeletal diseases (19.7%), cerebrovascular diseases (9.9%), emergency care and CPR (8.5%), and medical nursing (8.5%). Skillful nurses required cerebrovascular diseases (13.9%), care for internal diseases (8.9%), and rehabilitation care (8.9%). Among the educational contents of diseases, the items that were significantly different according to practical experience were operation management ($x^2$=23.92, p<.001) and drug care ($x^2$=7.85, p=.020). Among continuing education methods, the items that were significantly different were video ($x^2$=16.81, p<.001), webtoon ($x^2$=8.96, p=.011), and test ($x^2$=10.56, p=.005). Among continuing education evaluation methods, the items that were significantly different were multiple-choices ($x^2$=9.43, p=.009) and OX ($x^2$=6.47, p=.039) based quizzes. Conclusion: Based on the study results, it is necessary to develop a differentiated continuing education program according to practical experience of nurses.

Growth of $Cd_{1-x}Zn_xS $ Thin films Using Hot Wall Epitaxy Method and Their Photoconductive Characteristics (HWE에 의한 $Cd_{1-x}Zn_xS $박막의 성장과 광전도 특성)

  • 홍광준;유상하
    • Korean Journal of Crystallography
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    • v.9 no.1
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    • pp.53-63
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    • 1998
  • The Cd1-xZnxS thin films were grown on the Si(100) wafers by a hot wall epitaxy method (HWE). the source and substrate temperature are 600℃ and 440℃, respectively. The crystalline structure of epilayers was investigated by double crystal X-ray diffraction (DCXD). Hall effect on the sample was measured by the van der Pauw method and the carrier density and mobility dependence of Hall characteristics on temperature was also studied. In order to explore the applicability as a photoconductive cell, we measured the sensitivity (γ), the ratio of photocurrent to darkcurrent (pc/dc), maximum allowable power dissipation (MAPD), spectral response and response time. The results indicated that the best photoconductive characteristic were observed in the Cd0.53Zn0.47S samples annealed in Cu vapor comparing with in Cd, Se, air and vacuum vapour. Then we obtained the sensitivity of 0.99, the value of pc/dc of 1.65 × 107, the MAPD of 338mW, and the rise and decay time of 9.7 ms and 9.3 ms, respectively.

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A study on fabrecation and characteristics of short channel SNOSFET EEPROM (Short channel SNOSFET EEPROM의 제작과 특성에 관한 연구)

  • 강창수;김동진;서광열
    • Electrical & Electronic Materials
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    • v.6 no.4
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    • pp.330-338
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    • 1993
  • Channel의 폭과 길이가 15 x 15.mu.m, 15 x 1.5.mu.m, 1.9 x 1.7.mu.m인 비휘발성 SNOSFET EEPROM 기억소자를 CMOS 1 Mbit 설계규칙에 의하여 제작하고 체널크기에 따른 $I_{D}$- $V_{G}$특성 및 스위칭 특성을 조사하여 비교하였다. 게아트에 전압을 인가하여 질화막에 전하를 주입시키거나 소거시킨 후 특성을 측정한 결과, 드레인전류가 적게 흐르는 저전도상태와 전류가 많이 흐르는 고전도상태로 되는 것을 확인하였다. 15 x 15.mu.m의 소자는 전형적인 long channel특성을 나타냈으며 15 x 1.5.mu.m, 1.9 x 1.7.mu.m는 short channel특성을 보였다. $I_{D}$- $V_{G}$ 특성에서 소자들의 임계 문턱전압은 저전도상태에서 $V_{W}$=+34V, $t_{W}$=50sec의 전압에서 나타났으며 메모리 윈도우 폭은 15 x 15.mu.m, 15 x 1.5.mu.m, 1.9 x 1.7.mu.m의 소자에서 각각 6.4V, 7.4V, 3.5V였다. 스위칭 특성조사에서 소자들은 모두 논리스윙에 필요한 3.5V 메모리 윈도우를 얻을 수 있었으며 논리회로설계에 적절한 정논리 전도특성을 가졌다.특성을 가졌다.다.다.

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Quality Score Index as a Criterion for Wheat Quality (품질평점지수(品質評點指數)에 의한 소맥품질(小麥品質)의 평가방법(評價方法))

  • Ryu, In-Soo;Shin, Hyun-Kuk;Bae, Sung-Ho
    • Applied Biological Chemistry
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    • v.21 no.3
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    • pp.193-196
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    • 1978
  • Wheat quality score index was proposed as a new criterion of wheat_quality for evaluation of the laboratory testing value such as milling rate (Xm), flour ash content (Xa), flour protein content (Xp) and sedimentation value (Xs). 1) Wheat quality score index was expressed as follows; Milling score index (MSI) $=2.3X_m-72.4X_a$ Protein score index (PSI) =$5.2X_p+0.9X_{psi}$ Composite quality score index (QSI) =$0.63X_{msi}+0.37X_{psi}$ 2) The samples with the more than 100 of MSI would be the good milliability, and the samples with more than 100 of PSI would be the good bread making properties, while that with less than 100 of PSI be good pastry type properties. Whereas most of the samples with higher value of QSI would be related to the good milliability and good bread making properties. 3) MSI, PSI and QSI were significantly correlated to the each related quality components.

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Light modulation properties of the penferroelectric BLN-PZT ceramics (준강유전 BLZ-PZT 세라믹의 광변조특성)

  • 류기원;정장호;박인길;이영희
    • Electrical & Electronic Materials
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    • v.6 no.5
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    • pp.454-460
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    • 1993
  • 본 연구에서는 준강유전 특성을 갖는 xBa(L $a_{1}$2/N $b_{1}$2/) $O_{3}$- (1-x)Pb(Z $r_{y}$ $Ti_{1-y}$) $O_{3}$ (x=8.5, 9.0[mol.%], y=65, 70[mol.%]) 세라믹을 2단 소성법으로 제작한 후, 조성 및 인가전계에 따른 전기광학 특성 및 광변조 특성을 측정하였다. 인가전계가 증가함에 따라 8.5/65/35 시편을 제외한 전조성에서 유효복굴절이 2차 함수적으로 변화하는 2차 전기광학 특성을 나타내었으며 2차 전기광학계수, 반파장전압 및 ON-OFF ratio는 9.0/65/35 시편에서 각각 6.17x$10^{-16}$[ $m^{2}$/ $v^{2}$], 136[V], 252의 가장 우수한 값을 나타내었다. 9.0/70/30, 9.0/65/35 및 8.5/70/30 시편에 대해 광변조 특성을 측정한 결과, 입사광의 세기를 인가전압에 의해 변조시킬 수 있음을 관찰하였다.다.

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