• Asian Journal for Public Opinion Research
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• v.11 no.2
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• pp.75-76
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• 2023

• Clinical and Experimental Vaccine Research
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• v.11 no.2
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• pp.233-234
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• 2022

• Bulletin of the Korean Chemical Society
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• v.11 no.6
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• pp.531-534
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• 1990

The reaction of $Os_3(CO)_{10}(NCMe)_2$ with a tungsten alkylidyne $Cp(CO)_2W{\equiv}CTol(Cp={\eta}^5-C_5H_5,\;Tol=p-C_6H_4Me)$ produces the compound, $CpWOs_3(CO)_{11}({\mu}_3-CTol)$(1). The structure of compound 1 can be viewed as one in which the metalla-alkyne, $Cp(CO)_2W{\equiv}CTol$, is ${\mu}_3-{\eta}^2-{\bot}$ (perpendicular) bound to an $Os_3(CO)_9$ fragment. Variable-temperature $^{13}C$ NMR spectra of 1 show no evidence for the analogous rotation of the metalla-alkyne molecule as shown alkyne rotation in $Os_3(CO)_9(C_2Tol_2)$ compound. This lack of the metalla-alkyne fluxionality supports the apparent saturated nature of compound 1.

• Korean Architects
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• s.663
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• pp.114-115
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• 2024

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.11B
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• pp.965-971
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• 2003

This paper suggests a low-complexity frame timing synchronization system for IEEE802.11a wireless LAN systems. The proposed timing synchronization scheme has been implemented by correlating the received OFDM preamble with quantized coefficients composed of ｛0, ${\pm}$2$^{0}$ , ${\pm}$2$^1$‥‥‥ ${\pm}$2$^{i}$ ), where i is an integer number. The 2$^{i}$ -valued coefficients enable the multipliers in the correlation system to be simplified to i-bit shifters. So we can design the correlation system using shifters instead of multipliers. We estimate the performance of the proposed scheme in comparison with conventional systems under the AWGN and Rayleigh fading channels. In this paper we show that the complexity can be reduced by 90% while still maintaining a performance comparable to that of the conventional system.

• Journal of Korean Academy of Nursing
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• v.3 no.3
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• pp.73-77
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• 1973

A study on the nutritional status for school-children has been carried out 1,700 school- children of Song-do primary school located in Song-do beach, Busan, Korea, from November to-December, 1972. The evaluation of the nutritional status has been carried out through skin-fold thickness and hemoglobin. The summarized results were as follows. : 1. Skinfolds thickness 1) Subcellular skinfolds thickness . Among boys, that was 3.5mm in the age 6 and 5.4mm in the age 11 Among girls, that was 4.2mm in the age 6 and 7.6mm in the age 11. Girls were thicker than toys in the all age. 2) Upper-arm skinfolds thickness Among boys, that was 5.0mm in the age 6 and 6.8mm in the age 11. Among girls, that was 6.2mm in the age 6 and 8.7mm in the age 11. Girls were thicker than toys in the all age. 3)Abdominal skinfolds thickness. Among boys, that was 4.0mm in the age 6, and 6.4mm in the age 11. Among girls that was 4.0mm in the age 0, and 8.4mm in the age 11. Girls were thicker than boys in the all age. 2. Hemoglobin Proportional range of hemoglobin were observed as 12.2-12.8 gm/㎗.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.2 no.2
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• pp.137-142
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• 2016

We have successfully synthesized of 4-cyano-1-(2,4-dichlorophenyl)-5-(4-[$^{11}C$]methoxyphenyl)-N-(piperidin-1-yl)-1H-pyrazole-3-carboxzmide ([$^{11}C$]OMAR), which has been shown a progressing candidate to human brain PET study, from fully automated loop method using ethanol as the only solvent for the entire manufacturing process. The radiochemical yield of [$^{11}C$]OMAR was observed in $4.1{\pm}0.2%$ with $4990{\pm}384Ci/mmol$ of the specific activity and total synthesis time was about 45 minutes after HPLC purification (n = 3, decay corrected) from ethanolic loop system, which was exhibited to better results compared with conventional methods. Ethanolic loop chemistry is favorable and efficient method by simplifies manufacturing procedures as well as satisfied suitable for human administration.

• Bulletin of the Korean Chemical Society
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• v.8 no.3
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• pp.147-149
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• 1987

The out-of-plane bending, vibrational-rotational FT-IR spectra of dichloroborane molecule were analyzed. The band centers are 785.992, 785.723, 647.217, and 646.997 $cm^{-1}$ and centrifugal distortion constants are $2.2{\times}10^{-6},\;5.5{\times}10^{-6},\;0.2{\times}10^{-6}$, and $0.7{\times}10^{-6}cm^{-1}$ for $H^{11}B^{35}Cl_2$, $H^{11}B^{35}Cl^{37}Cl$, $D^{11}B^{35}Cl_2$, and $D^{11}B^{35}Cl^{37}Cl$, respectively. The theoretical spectrum of $D^{11}B^{36}Cl_2$ was plotted to conform the molecular constants and the rotational constants for the first excited vibrational state of this molecule were A' = 1.165932, B' = 0.106166, and C' = 0.097229 $cm^{-1}$. The calculated spectra were in good agreement with the observed spectra.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.8
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• pp.667-674
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• 2000

The stability of ZnO-Pr$_{6}$/O$_{11}$-CoO-Er$_{2}$/O$_3$based varistors was investigated with Er$_{2}$/O$_3$additive content of the range 0.0 to 2.0 mol%. All varistors sintered at 130$0^{\circ}C$ exhibited the thermal runaway within short times even under weak d.c. stress. As a result these varistors were completely degraded. On the contrary the stability of varistors sintered at 135$0^{\circ}C$ was far better than that of 130$0^{\circ}C$. In particular the varistors added with 0.5mol% Er$_{2}$/O$_3$ which the nonlinear exponent is 34.83 and the leakage current is 7.38 $mutextrm{A}$ showed a excellent stability which the variation rate of the varistors voltage the nonlinear coefficient and the leakage current is below 1%, 2%, and 3.5% respectively even under more severe d.c. stress such as (0.80 V$_{1mA}$9$0^{\circ}C$/12h)+(0.85 V$_{1mA}$115$^{\circ}C$/12h)+(0.90 V$_{1mA}$12$0^{\circ}C$12h) Consequently it is estimated that the ZnO-0.5 mol% Pr$_{6}$/O sub 11/-1.0 mol% CoO-0.5 mol% Er$_{2}$/O sub 3/ based varistors will be used to develop the advanced Pr$_{6}$/O$_{11}$-1.0 mol% CoO-0.5 mol% Er$_{2}$/O$_{3}$ based varistors will be used to develop the advanced Pr$_{6}$/O$_{11}$-based ZnO varistors having the high performance and stability in future. future.ure. future.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.422-425
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• 2001

The electrical properties of ZnO-Pr$_{6}$O$_{11}$-CoO-Cr$_2$O$_3$-La$_2$O$_3$ based varistors were investigated with sintering temperature in the range of 1240~130$0^{\circ}C$. The varistors sintered at 1240~126$0^{\circ}C$ exhibited high density, which was 5.50~5.70 g/㎤ corresponding to 95.2~98.6% of theoretical density The varistor voltage was decreased in range of 718.47~108.00 V/mm with increasing sintering temperature. The varistors sintered at 1240~126$0^{\circ}C$ exhibited good electrical properties, in which the nonlinear exponent is in the range of 79.25~49.22 and leakage current is in the range of 0.26~1.00 $\mu$A. In particular, the varistor sintered at 1240\`c showed very excellent electrical properties, in which the nonlinear exponent is 79.25 and leakage current is 0.26 $\mu$A.A.A.