• Title/Summary/Keyword: Standard C/T

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Sublimation Pressure and Standard Enthalpy of Bismuth Triiodide by Torsion-Effusion Method (Torsion-Effusion 법에 의한 Bismuth Triiodide의 승화압과 표준 엔탈피)

  • 김준학
    • Journal of the Korean Ceramic Society
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    • v.28 no.2
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    • pp.109-118
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    • 1991
  • Steady-state sublimation vapour pressures of anhydrous bismuth triiodide have been measured by the torsion-effusion method from 488.8 to 570.5 K and equilibrium sublimation pressures were obtained from the steady-state data. The standard sublimation enthalpy changes derived by both second(modified sigma function) and third(average enthalpy method) law methods were 159.316${\pm}$0.055, 137.67${\pm}$1.43 kJ$.$mol-1 respectively. The standard sublmation entropy change derived by modified sigma function was 232.88${\pm}$0.10 J$.$K-1$.$mol-1. The reliable standard sublimation enthalpy change based on a correlation of {{{{ { TRIANGLE }`_{cr } ^{g } }} H{{{{ { 0} atop {m } }}(298.15K) and {{{{ { TRIANGLE }`_{cr } ^{g } }} S{{{{ { 0} atop {m } }}(298.15K), a recommended p(T) equation has been obtained for BiI3(cr) ; lg(p/Pa)=-(C$.$K/T)+5.071lg(T/K)-2.838${\times}$10-3(T/K)-7.758${\times}$103(K/T)2+1.4519 where C={{{{{ { TRIANGLE }`_{cr } ^{g } }} H{{{{ { 0} atop {m } }}(298.15K)/0.019146 kJ$.$mol-1}-456.27.

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ON FRAMES FOR COUNTABLY GENERATED HILBERT MODULES OVER LOCALLY C*-ALGEBRAS

  • Alizadeh, Leila;Hassani, Mahmoud
    • Communications of the Korean Mathematical Society
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    • v.33 no.2
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    • pp.527-533
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    • 2018
  • Let $\mathcal{X}$ be a countably generated Hilbert module over a locally $C^*$-algebra $\mathcal{A}$ in multiplier module M($\mathcal{X}$) of $\mathcal{X}$. We propose the necessary and sufficient condition such that a sequence $\{h_n:n{{\in}}\mathbb{N}\}$ in M($\mathcal{X}$) is a standard frame of multipliers in $\mathcal{X}$. We also show that if T in $b(L_{\mathcal{A}}(\mathcal{X}))$, the space of bounded maps in set of all adjointable maps on $\mathcal{X}$, is surjective and $\{h_n:n{{\in}}\mathbb{N}\}$ is a standard frame of multipliers in $\mathcal{X}$, then $\{T{\circ}h_n:n{\in}\mathbb{N}}$ is a standard frame of multipliers in $\mathcal{X}$, too.

Magnetic $T_c$ Measurements of Composite Superconductors for a Standard Method (복합초전도체의 자기적 임계온도 측정의 표준화연구)

  • Lee K. W;Kim M. S;Kim D. H;Lee S. G
    • Progress in Superconductivity
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    • v.6 no.1
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    • pp.24-31
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    • 2004
  • Magnetic $T_{c}$ of composite superconductors has been studied for providing a standard method. Various magnetization-temperature curves of NbTi, $Nb_3$Sn and Bi-2223 wires were measured using a SQUID magnetometer. Magnetization-temperature curve of zero-field-cooled procedure showed larger values than fie Id-cooled procedure. To obtain higher resolution near the onset temperature, we employed a two-field-direction method which measures a magnetization-temperature curve of a specimen first in positive and then negative fields. Analytical comparison of the magnetic $T_{c}$, with the resistive T$_{c}$ was accomplished for three specimens. The magnetic $T_{c}$/ mettled showed more detailed information on superconducting state of a specimen than the resistive$T_{c}$/ method. We have also studied the field dependence of the magnetic $T_{c}$ from 5 Oe to 120 Oe, however, no significant difference on field strength was found in our three specimensns

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The Sublimation Pressure and Standard Enthalpy of Sublimation of Bismuth Triiodide ($BiI_3$에 대한 승화압과 승화 표준 엔탈피)

  • 김준학
    • Journal of the Korean Ceramic Society
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    • v.27 no.7
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    • pp.943-951
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    • 1990
  • Steady-state sublimation vapour pressures of anhydrous bismuth triiodide have been measured by the continuous gravimetric Kundsen-effusion method from 430.0 to 558.9 K and equilibrium sublimation pressures were obtained from the steady-state data. Condensation coefficients and their temperature dependence have been derived from the effusiion measurement. Condensation coefficients ranged from 0.159 to 0.048(475 to 500K), the activation enthalpy and entropy for condensation have been obtained as -93.38kTmol-1 and -212.70JK-1mol-1. The standard sublimation enthalpy changes derived by both second(modified sigma function) and third(average enthalpy method) law methods were 138.261$\pm$0.023, 138.74$\pm$0.002kJmol-1 respectively. The standard sublimation entropy change derived by modified sigma function was 191.98$\pm$0.047 JK-1mol-1. The reliable standard sublimation enthalpy change based on a correlation of ΔgcrHom(298.15K) and ΔgcrSom(298.15K), a recommended p(T) equation has been obtained for BiI3(cr) ; 1g(p/Pa)=-C/(T/K)+5.0711g(T/K)-2.838$\times$10-3(T/K)-7.758$\times$103(K/T)2+1.4519 where p is in Pa, T in Kelvin, ΔgcrHom(298.15K) in kJmol-1 and C=(ΔgcrHom(298.15K)-8.7358)/1.9146$\times$10-2.

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BOUNDARY-VALUED CONDITIONAL YEH-WIENER INTEGRALS AND A KAC-FEYNMAN WIENER INTEGRAL EQUATION

  • Park, Chull;David Skoug
    • Journal of the Korean Mathematical Society
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    • v.33 no.4
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    • pp.763-775
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    • 1996
  • For $Q = [0,S] \times [0,T]$ let C(Q) denote Yeh-Wiener space, i.e., the space of all real-valued continuous functions x(s,t) on Q such that x(0,t) = x(s,0) = 0 for every (s,t) in Q. Yeh [10] defined a Gaussian measure $m_y$ on C(Q) (later modified in [13]) such that as a stochastic process ${x(s,t), (s,t) \epsilon Q}$ has mean $E[x(s,t)] = \smallint_{C(Q)} x(s,t)m_y(dx) = 0$ and covariance $E[x(s,t)x(u,\upsilon)] = min{s,u} min{t,\upsilon}$. Let $C_\omega \equiv C[0,T]$ denote the standard Wiener space on [0,T] with Wiener measure $m_\omega$. Yeh [12] introduced the concept of the conditional Wiener integral of F given X, E(F$\mid$X), and for case X(x) = x(T) obtained some very useful results including a Kac-Feynman integral equation.

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Noise Performance Test and Evaluation of a Wind Turbing Generator (풍력발전기 소음 성능 실증)

  • Kim, Seock-Hyun;Kim, Tae-Hyung;Park, Moo-Yeol;Chui, C.C.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.05a
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    • pp.241-245
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    • 2005
  • This study introduces the wind turbine (W/T) noise evaluation procedure required in the international standard (IEC 61400-11) and monitoring system for the evaluation. Noise emission characteristics of a 750kW W/T generator is investigated. Test and evaluation are performed on J48 W/T model which is under operation in Daekwanryung Wind Test Site. With the noise signal, meteorological data and W/T operational data are monitored in real time by the integrated monitoring system using LabVIEW. From the measured noise data, acoustic power level and tonality of the W/T are estimated under the wind speeds required by the international standard.

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Technology Trends in Industrial Internet-of-Things Networks (산업용 사물인터넷 네트워크 기술 동향)

  • Kang, H.Y.;Park, M.R.;Lee, S.S.;Shin, C.S.;Park, C.W.
    • Electronics and Telecommunications Trends
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    • v.36 no.5
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    • pp.92-102
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    • 2021
  • Owing to various restrictions in-field application, the low-speed, low-power-based industrial Internet-of-Things (IoT) network built in extremely harsh industrial environment sites requires multi-hop, channel hopping, and low-latency transmission characteristics. In the past, wired networks were used in industrial facilities; however, network technologies based on the Industrial IoT Network standard standardized for industrial applications, such as WirelessIO link, WirelessHART, SmartMesh, and eStar Link satisfy industrial requirements. Recently, the use of industrial IoT networks in industrial facilities has rapidly expanded. This paper covers the developments in industrial IoT network technologies and summarizes the major industrial IoT standard technologies that meets the requirements of industrial sites.

Analysis of Cleavage Fracture Toughness of PCVN Specimens Based on a Scaling Model (PCVN 시편 파괴인성의 균열 깊이 영향에 대한 Scaling 모델 해석)

  • Park, Sang-Yun;Lee, Ho-Jin;Lee, Bong-Sang
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.33 no.4
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    • pp.409-416
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    • 2009
  • Standard procedures for a fracture toughness testing require very severe restrictions for the specimen geometry to eliminate a size effect on the measured properties. Therefore, the used standard fracture toughness data results in the integrity assessment being irrationally conservative. However, a realistic fracture in general structures, such as in nuclear power plants, may develop under the low constraint condition of a large scale yielding with a shallow surface crack. In this paper, cleavage fracture toughness tests have been made on side-grooved PCVN (precracked charpy V-notch) type specimens (10 by 10 by 55 mm) with various crack depths. The constraint effects on the crack depth ratios were evaluated quantitatively by the developed scaling method using the 3-D finite element method. After the fracture toughness correction from scaling model, the statistical size effects were also corrected according to the standard ASTM E 1921 procedure. The results were evaluated through a comparison with the $T_0$ of the standard CT specimen. The corrected $T_0$ for all of the PCVN specimens showed a good agreement to within $5.4^{\circ}C$ regardless of the crack depth, while the averaged PCVN $T_0$ was $13.4^{\circ}C$ higher than the real CT test results.

Cell transformation of bisphenol A in Syrian hamster embryo cells and mouse embryo BalB/c 3T3 cells (Syrian hamster embryo 세포와 mouse embryo BalB/c 3T3 세포에서의 bisphenol A의 세포 형질전환 연구)

  • 김종원;한의식;박미선;엄미옥;전혜승;민수진;김인숙;정해관;심웅섭
    • Environmental Mutagens and Carcinogens
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    • v.21 no.1
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    • pp.44-50
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    • 2001
  • To identify nongenotoxic carcinogen determined as negative by ICH guideline-recommended standard genotoxicity test battery; Ames test, chromosome aberration assay, mouse lymphoma $tk^{+/-}$ assay, in vivo micronucleus assay, we picked bisphenol A as a model compound. In this study, we applied in vitro BalB/c 3T3 cell transformation assay and Syrian hamster embryo (SHE) cell transfarmation assay. Bisphenol A was treated upto $769.2 ug/m{\ell}$ in BalB/c 3T3 cells and upto $125 ug/m{\ell}$ in SHE cells. bisphenol A didn't induced morphological transformation both with one stage treatment protocol and with two stage treatment protocol. But, treated far 48 hr, Bisphenol A induced morphological transformation significantly in SHE cells.

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Construction of Low Magnetic Standard System using a Multi-layer Solenoid with Single-current (단전류-다층 솔레노이드 방법을 사용한 저자장 표준시스템 제작)

  • 박포규;김영균
    • Journal of the Korean Magnetics Society
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    • v.11 no.1
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    • pp.38-44
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    • 2001
  • The magnetic field standard below 1 mT with the resolution of 0.26 nT has been established. Earth magnetic field (EMF) is compensated automatically down to 0.1 nT/10 min. by a closed feedback system with Cs optical pumping magnetometer and 3-axis Helmholtz coils in nonmagnetic facilities. A multi-layer precision solenoid with the optimized single-current method generates the uniform magnetic field better than 1.0$\times$10$\^$-7/ within $\pm$ 1 cm region at its center. The coil constant of solenoid determined from Helium optical pumping magnetometer is 1.231 058 9 mT/A, and temperature coefficient is 0.38 nT/$\^{C}$. This standard system is used for calibration of low field magnetometers and testing relates to low field.

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