• Title/Summary/Keyword: X-factor

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The Study on Measurement of Relative Conversion Factor in X-ray Image Intensifier (X선영상증배관의 상대변환계수 측정에 관한 검토)

  • Kim, Sung-Chul;Shin, Sung-Ill;Lee, Sun-Sook;Huh, Joon;Kim, Sung-Soo
    • Journal of radiological science and technology
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    • v.20 no.2
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    • pp.28-33
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    • 1997
  • For the Evaluation of X-ray image intensifier, we measured radiation dose at input of I. I., brightness and fluorescence at output of I. I. by using X-ray exposure meter, optometer and fluorescence meter for the relative conversion factor. Especially, by using fluorescence meter, we could easily get relative conversion factor without having regulated machine by JIS. Since using, the quality of image intensifier is going down. Consequently, it needs continuous quality maintenance.

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Synthesis and characterization of thermoelectric Zn1-xAgxSb compounds (열전재료 Zn1-xAgxSb의 제조와 특성)

  • Kim, In-Ki;Oh, Han-Jun;Jang, Kyung-Wook
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.27 no.4
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    • pp.162-166
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    • 2017
  • Thermoelectric compounds of $Zn_{1-x}Ag_xSb$ with x = 0~0.2 were prepared by vacuum melting and quenching process and their crystal phases and thermoelectric properties were examined. It was found that free metallic Sb phases were formed in the compound with x = 0.05, leading to increasing the electrical conductivities. The power factors were significantly affected by the electrical conductivity rather than Seebeck coefficient. When x > 0.05, the peak intensities of $Ag_3Sb$ phases in XRD patterns were increased and those of free Sb phases were weakened. These changes of second phases resulted in decreasing the electrical conductivities and the power factors and became more obvious in the compound with x = 0.2.

The Methods Calculating the Reduction Efficiency of Nitrogen Oxide for the Facilities Including the Low NOx Burners (저녹스 버너 설치 시설의 질소산화물 저감 효율 산정 방법)

  • Lee, Ki Yong;Talukder, Niladri
    • 한국연소학회:학술대회논문집
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    • 2015.12a
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    • pp.295-296
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    • 2015
  • We presented the methods calculating the reduction efficiency of nitrogen oxide for the low $NO_x$ burner as the pollution prevention facilities. The standard $NO_x$ concentration was used on the emission factor of LNG, $3.7g/m^3$. The $NO_x$ reduction efficiency based on the $NO_x$ concentration was presented and the relationships between the $NO_x$ concentration and the emission factor or the specific heat emission factor were derived. These results could be accurately reflected on calculating the amount of the nitrogen oxide emissions. In addition, according to the arrangement of the low $NO_x$ burners the methods of applying their $NO_x$ reduction efficiency were proposed. The $NO_x$ reduction efficiency for the facilities consisting of the low $NO_x$ burners and the non-low $NO_x$ burners could be estimated with information about the reduction efficiency of each low $NO_x$ burners, the fuel consumption rate, and the heating value of fuel.

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The Dielectric and Piezoelectric Properties of (Pb1-1.5xLax)(Ti1-yMny) System ((Pb1-1.5xLax)(Ti1-yMny)O3계의 유전 및 압전성질)

  • 맹성재;정형진
    • Journal of the Korean Ceramic Society
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    • v.25 no.4
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    • pp.321-328
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    • 1988
  • The sintering phenomena, electrical resistivity, dielectric and piezoelectric properties of lead titanate ceramics modified by the partial substitution of La for Pb and Mn for Ti, (Pb1-1.5xLax)(Ti1-yMny)O3 ceramics, have been investigated. In (Pb1-1.5xLax)(Ti1-yMny)O3 system, with increasing lanthanum content, the realtive bulk density increased, but the Curie point and tetragonality (c/a) decreased. The tetragonal-to-cubic phase transition boundary existed in the range of 0.20

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Factor Rank and Its Preservers of Integer Matrices

  • Song, Seok-Zun;Kang, Kyung-Tae
    • Kyungpook Mathematical Journal
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    • v.46 no.4
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    • pp.581-589
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    • 2006
  • We characterize the linear operators which preserve the factor rank of integer matrices. That is, if $\mathcal{M}$ is the set of all $m{\times}n$ matrices with entries in the integers and min($m,n$) > 1, then a linear operator T on $\mathcal{M}$ preserves the factor rank of all matrices in $\mathcal{M}$ if and only if T has the form either T(X) = UXV for all $X{\in}\mathcal{M}$, or $m=n$ and T(X)=$UX^tV$ for all $X{\in}\mathcal{M}$, where U and V are suitable nonsingular integer matrices. Other characterizations of factor rank-preservers of integer matrices are also given.

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Development of a Highly Active Fluorescence-Based Detector for Yeast G Protein-Coupled Receptor Ste2p

  • Hong, Jin Woo;Ahn, Hee Jun;Baek, Jee Su;Hong, Eun young;Jin, Dong Hoon;Khang, Yong Ho;Hong, Nam Joo
    • Journal of Microbiology and Biotechnology
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    • v.28 no.10
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    • pp.1589-1603
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    • 2018
  • Twenty analogs of $[Orn^6,D-Ala^9]{\alpha}-factor$ were synthesized and assayed for their biological activities: seven analogs of $[Orn^6,X^9]{\alpha}-factor$, seven analogs of $[X^6,D-Ala^9]{\alpha}-factor$, five analogs of $[X^5,X^6,D-Ala^9]{\alpha}-factor$, and native ${\alpha}-factor$ (X = amino acids). Their biological activities (halo, gene induction, and affinity) were measured using S. cerevisiae Y7925 and LM102 and compared with those of native ${\alpha}-factor$ (100%). G protein-coupled receptor was expressed in strain LM102 containing pESC-LEU-STE2 vector. $[Dap^6,D-Ala^9]{\alpha}-factor$ with weak halo activity (10%) showed the highest receptor affinity (> 230%) and the highest gene induction activity (167%). $[Arg^6,D-Ala^9]{\alpha}-factor$ showed the highest halo activity (2,000%). The number of active binding sites per cell (about 20,000 for strain LM102) was determined using a newly-designed fluorescence-based detector, $[Arg^6,D-Ala^9]{\alpha}-factor-Edan$, with high sensitivity (12,500-fold higher than the absorption-based detector $[Orn^6]{\alpha}-factor-[Cys]_3$).

Microwave Dielectric Properties of (1-x)ZnWO4-xTiO2 Ceramics ((1-x)ZnWO4-xTiO2 세라믹스의 마이크로파 유전특성)

  • 윤상옥;김대민;심상흥;강기성
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.5
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    • pp.397-403
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    • 2003
  • Microwave dielectric properties of (1-x)ZnW $O_4$-xTi $O_2$ ceramic systems were investigated with calcination temperatures and Ti $O_2$ contents. The ZnW $O_4$ ceramic could be suitably sintered at 1075$^{\circ}C$ and showed the dielectric constant of 13.6, quality factor(Q$\times$ $f_{O}$value) of 22,000 and temperature coefficient of resonant frequency($\tau$$_{f}$) of -65$\pm$2ppm/$^{\circ}C$. Increasing the amount of Ti $O_2$ in the range of 0.25 to 0.45 mol, the dielectric constant and $\tau$$_{f}$ increased due to the role of Ti $O_2$ but the quality factor decreased due to the increase of phase boundaries. The 0.7ZnW $O_4$-0.3Ti $O_2$ ceramic showed the dielectric constant of 19.8, qualify factor(Q$\times$ $f_{0}$) of 20,000 and $\tau$$_{f}$ of -3$\pm$1ppm/$^{\circ}C$.>.EX>.>.>.

Out-of-Plane Elastic Buckling of X-Bracing System with Fixed Ends (고정 지점을 갖는 X-브레이싱의 탄성 면외 좌굴)

  • Moon, Ji-Ho;Yoon, Ky-Yong;Lee, Hak-Eun
    • 한국방재학회:학술대회논문집
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    • 2007.02a
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    • pp.293-296
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    • 2007
  • This study investigated the out-of-plane elastic buckling load and effective length factor of X-bracing system. The members of X-bracing system which are studied in this paper are rigidly attached to the structure at their end connections, and are pinned or rigidly connected at their point of intersection. The effective length factors are derived for the general case where the tension and compression brace have different material and geometrical properties.

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A Quantitative Interpretation of the Overlapped X-Ray Fluorescence Spectra by Target Transformation Factor Analysis (Target Transformation Factor Analysis에 의한 겹침 X-선 형광 스펙트라의 정량적 해석)

  • Kim Seungwon;Lee, Chul;Choi Sang Won;Kang Hyung Tae
    • Journal of the Korean Chemical Society
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    • v.36 no.5
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    • pp.720-726
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    • 1992
  • Multivariate analysis such as factor analysis was applied to interpret multivariate data, which were obtained from the overlapped X-ray fluorescence spectra. X-ray fluorescence spectra of 11 reference samples were obtained by the wavelength dispersive spectrometer at a specified range of angle such as $33.50∼34.50^{\circ}$. The data matrix was made from the spectra of 8 samples. The results of abstract factor analysis gave three factors. By the target testing with 8 elements contained in the reference samples, the three factors were found to be Pb, As and Cu. The concentration of these elements in the test samples was determined by target transformation factor analysis regardless overlapping individual peaks.

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Microwave Dielectric Properties of the ($Ba_{1-x}Sr_{x}$)O-$Sm_2O_3$-$TiO_2$ Ceramics. (($Ba_{1-x}Sr_{x}$)O-$Sm_2O_3$-$TiO_2$세라믹스의 마이크로파 유전특성)

  • 박인길;류기원;배선기;이영희
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1995.11a
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    • pp.5.2-8
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    • 1995
  • 0.15($Ba_{1-x}Sr_{x}$)O-$0.15Sm_2O_3$-$0.7TiO_2$(x=0∼9[m/o]ceramics were fabricated by mixed-oxide method. Microwave dielectric properties were investigated with sintering conditions aid Sr addictive. In the specimen with x=0[m/o] sintered at 1350∼1470[$^{\circ}C$], dielectric constant, quality factor and temperature coefficient of resonant frequency were 70∼74, 2800∼3300(at 3[GHz]), -1.33∼+l.66[ppm/$^{\circ}C$, respectively. Increasing the Sr additive from 0 to 5[m/o], dielectric constant and temperature coefficient of resonant frequency were increased and quality factor was decreased. In the specimen with x=r[m/o] sintered at 1375[$^{\circ}C$], 6[hr], dielectric constant, quality factor and temperature coefficient resonant frequency were 75.62, 2785(at 3[GHz]), +8.39[ppm/$^{\circ}C$], respectively.