• Bulletin of the Korean Chemical Society
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• v.13 no.1
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• pp.11-17
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• 1992

Vibration-to-vibration energy transfer probabilities for $HF(v=n)+H_2(v=0){\to}HF(v=n-1)+H_2(v=1)$ and $DF(v=n)+D_2(v=0){\to}DF(v=n-1)+D_2(v=1)$ including both the vibration-to-vibration and translation (V-V, T) and vibration-to-vibration and rotation (V-V, R) energy transfer paths have been calculated semiclassically using a simplified collision model and Morse-type intermolecular interaction potential. The calculated results are in reasonably good agreement with those obtained by experimental studies. They also show that the transition processes for $HF(v=1-3)+H_2(v=0){\to}HF(v=0-2)+H_2(v=1)$ and $DF(v=1,\;4)+D_2(v=0){\to}DF(v=0,\;3)+D_2(v=1)$ are strongly dependent on the V-V, T path at low temperature but occur predominantly via the V-V, R path with rising temperature. The vibration-to-vibration energy transfer for $HF(v=4)+H_2(v=0){\to}HF(v=3)+H_2(v=1)$ and $DF(v=2-3)+D_2(v=0){\to}DF(v=1-2)+D_2(v=1)$ occur predominantly via V-V, R path and V-V, T path through whole temperatures, respectively.

• ETRI Journal
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• v.30 no.4
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• pp.526-534
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• 2008

This paper presents a fully integrated 0.13 ${\mu}m$ CMOS MB-OFDM UWB transmitter chain (mode 1). The proposed transmitter consists of a low-pass filter, a variable gain amplifier, a voltage-to-current converter, an I/Q up-mixer, a differential-to-single-ended converter, a driver amplifier, and a transmit/receive (T/R) switch. The proposed T/R switch shows an insertion loss of less than 1.5 dB and a Tx/Rx port isolation of more than 27 dB over a 3 GHz to 5 GHz frequency range. All RF/analog circuits have been designed to achieve high linearity and wide bandwidth. The proposed transmitter is implemented using IBM 0.13 ${\mu}m$ CMOS technology. The fabricated transmitter shows a -3 dB bandwidth of 550 MHz at each sub-band center frequency with gain flatness less than 1.5 dB. It also shows a power gain of 0.5 dB, a maximum output power level of 0 dBm, and output IP3 of +9.3 dBm. It consumes a total of 54 mA from a 1.5 V supply.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.39 no.4
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• pp.329-335
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• 2013

Three-dimensional quantitative structure-activity relationships (3D-QSARs) models between the substituents with changing groups ($R_1$ & $R_2$) of 4-hydroxybenzyl alcohol (4-HBA) derivatives as substrate molecule and their inhibitory activities against tyrosinase were derived and discussed quantitatively. The optimized CoMSIA FF model showed the best predictability and fitness ($r^2$ = 0.858 & $q^2$ = 0.951). The contour maps of the optimized CoMSIA FF model showed that, the inhibitory activities of the analogues against tyrosinase were expected to increase when hydrophobic (Hy) favor, negative charge (E) favor, steric (S) disfavor and hydrogen bond donor (HD) disfavor groups were substituted at the $R_2$ position. When the hydrogen bond donor (HD) favor groups were substituted at the $R_1$ position, it is predicted that the substituents will be able to increase the inhibitory activity.

• The Pure and Applied Mathematics
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• v.23 no.4
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• pp.347-375
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• 2016

Let R be a 3!-torsion free noncommutative semiprime ring, U a Lie ideal of R, and let $D:R{\rightarrow}R$ be a Jordan derivation. If [D(x), x]D(x) = 0 for all $x{\in}U$, then D(x)[D(x), x]y - yD(x)[D(x), x] = 0 for all $x,y{\in}U$. And also, if D(x)[D(x), x] = 0 for all $x{\in}U$, then [D(x), x]D(x)y - y[D(x), x]D(x) = 0 for all $x,y{\in}U$. And we shall give their applications in Banach algebras.

• Journal of Animal Environmental Science
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• v.12 no.3
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• pp.123-132
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• 2006

This study was conducted to determine the volume of Holstein heifers manure excreted and its characteristics. The average dry matter intake of heifers was 6.7 kg/head/day. The intake rate was lowest in spring among four seasons. The average dry matter intake rate during spring, summer, fall, and winter was 4.6, 8.3, 7.1, and 6.8 kg/head/day, respectively. The average water intake of heifers was $19.3{\ell}/head/day$. The wale. consumption was highest value ($21.8{\ell}/head/day$) in summer and lowest values ($18.3{\ell}/head/day$) in spring and winter. Values were found not to be statiscally different for the four seasons. The average manure production of heifers (average live weight was 363.1 kg) was 20.3 kg/head/day and it was 5.6% of live animal weight. The manure production during spring, summer, fall, and winter was 13.7, 23.5, 25.0, and 20.2 kg/head/day, respectively. Production during spring was lower than the other seasons (p<0.05). A higher correlation between live weight and manure production ($R^2=0.7816$) and between live weight and feed intake ($R^2=0.7296$) was observed for heifers. Correlations between manure production and water intake and between manure production and feed intake were found to be relatively low for heifers. The moisture content of feces was 83.5% and that of urine 94.6%. The pH of feces and urine were in the ranges of 7.4 and 7.5, respectively. The $BOD_5$, COD, SS, T-N, T-P concentrations of the heifer feces were 18,048, 50,114, 119,833, 2,519, and $427mg/{\ell}$, respectively. Heifer urine showed lower levels of $BOD_5(5,434mg/{\ell})$, COD$(6,550mg/{\ell})$, SS$(825mg/{\ell})$, T-N$(3,616mg/{\ell})$, and $T-P(28mg/{\ell})$ than feces. The fertilizer nutrient concentrations of heifer feces was 0.25% N, 0.1% $P_2O_5$ and 0.14% $K_2O$. Urine was found to contain 0.36% N, 0.006% of $P_2O_5$ and 0.31% $K_2O$.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.36 no.2
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• pp.121-128
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• 2010

We investigated the effects of skin hydration and composition analysis of proteoglycan (chia seed polymer) produced from chia (Salvia hispanica) seed. The result showed that proteoglycan of chia seeds is composed of galactose (46.8 %), glucuronic acid (27.1 %), rhamnose (8.7 %), xylose (7.6 %), glucose (4.9 %), fructose (2.3 %), mannose (1.8 %), arabinose (0.9 %) and the amount of proteins contained is 31.3 mg/g with the constituent amino acid compositions (mg/g) of Asp (1.9), Glu (3.6), Ser (0.9), Gly (3.6), Thr (0.8), Arg (1.0), Ala (2.0), Tyr (0.4), Cys (4.8), Val (1.1), Phe (0.5), Ile (0.6), Leu (0.9). The molecular weight of the proteoglycan measured by GPC (Gel Permeation Chromatography) is the range of 100,000~250,000 Da and the average molecular weight is 170,000 Da. The moisturizing effects and trans-epidermal water loss (TEWL) of chia seed polymer in cosmetic products (O/W emulsion) were studied in vivo. Chia seed polymer showed good skin hydration effects when compared with sodium hyaluronate which is a common moisturizer. Taken all together, chia seed polymer should be a very useful cosmetic ingredient as a moisturizer and a protecting agent from various skin irritations.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.9
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• pp.930-935
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• 2009

This paper describes a miniaturezed metamaterial BT chip antenna for mobile devices. The size of the proposed antenna is $3.0\;mm(W){\times}2.0\;mm(L){\times}1.2\;mm(H)$. And it is fabricated by chip type. The zeroth-order resonant properties are analyzed by magnitude and phase distributions of the surface current using surface current scanning system. The antenna offers omni-directional radiation patterns and measured 3D average gain is over - 1.7 dBi.

• Journal of IKEEE
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• v.23 no.2
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• pp.425-430
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• 2019

This work describes the design and characterization of a X-band power amplifier (PA) monolithic microwave integrated circuit (MMIC) using a $0.25{\mu}m$ gate length gallium nitride (GaN) high electron mobility transistor (HEMT) technology. The developed X-band power amplifier MMIC has small signal gain of over 22.7 dB and saturated output power of 43.02 dBm (20.04 W) over the entire band of 9 to 10 GHz. Maximum saturated output power is a 43.84 dBm (24.21 W) at 9.5 GHz. Its power added efficiency (PAE) is 41.0~51.24% and the chip dimensions are $3.7mm{\times}2.3mm$, generating the output power density of $2.84W/mm^2$. The developed GaN power amplifier MMIC is expected to be applied in a variety of X-band radar applications.

• Journal of the Chungcheong Mathematical Society
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• v.31 no.1
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• pp.1-12
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• 2018

Let R be a 3!-torsion free noncommutative semiprime ring, and suppose there exists a Jordan derivation $D:R{\rightarrow}R$ such that $D^2(x)[D(x),x]=0$ or $[D(x),x]D^2(x)=0$ for all $x{\in}R$. In this case we have $f(x)^5=0$ for all $x{\in}R$. Let A be a noncommutative Banach algebra. Suppose there exists a continuous linear Jordan derivation $D:A{\rightarrow}A$ such that $D^2(x)[D(x),x]{\in}rad(A)$ or $[D(x),x]D^2(x){\in}rad(A)$ for all $x{\in}A$. In this case, we show that $D(A){\subseteq}rad(A)$.

• The Journal of Korean Academy of Prosthodontics
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• v.34 no.2
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• pp.320-334
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• 1996

Dental cast and die materials are essential material using in almost dental prsthodontic procedure and it's most important requirement is accuracy for reqorducing the oral anatomical structures. In this study, 5 abutments A, B, C, D, E were fabricated on the metal master model to simulate the arch form and specimens were poured with 4 cast materials. Inter-abutment distances, A-B, A-C, A-D, A-E, B-C, B-D were calculated using the photo-scanning and the deviations from the metal master model were also evaluated. The results were as follows; 1. The distance between A-B, A-C, A-D, A-E, B-C, B-D of the abutments A, B, C, D, E of each cast material was calculated. And after comparing the deviations between the metal master model. $Fujirock^{(R)}$ showed the lowest value with $0.20{\pm}0.22mm$, and the deviation increased in the order of $Suprastone^{(R)}$, Epoxy $Die^{(R)}$, Die $Keen^{(R)}$. There was significant difference between $Fujirock^{(R)}$ and Epoxy $Die^{(R)}$, Die $Keen^{(R)}$. 2. In each calculation area, the difference in measurements between cast material and metal master model showed singificant difference between A-B and Cross arch measure-ments of A-D, B-D, A-E(p<0.05). 3. The difference in measurements between cast material and metal master model in the A-B area showed $Fujirock^{(R)}$ to be the lowest with $0.05{\pm}0.04$mm and increased in the order of Die $Keen^{(R)}$, $Suprastone^{(R)}$, Epoxy $Dies^{(R)}$. There was significant difference between $Fujirock^{(R)}$ and $Suprastone^{(R)}$, Epoxy $Die^{(R)}$ (p<0.05). 4. The difference in measurements between cast material and metal master model in the B-C area showed $Fujirock^{(R)}$ to bo the lowest with $0.17{\pm}0.11$mm and increased in the order of $Suprastone^{(R)}$, Die $Keen^{(R)}$, Epoxy $Dies^{(R)}$. There was significant difference between $Fujirock^{(R)}$ and Die $Keen^{(R)}$, Epoxy $Die^{(R)}$(p<0.05). 5. The difference in measurements between cast material and metal master model in the B-D area showed $Fujirock^{(R)}$ to bo the lowest with $0.13{\pm}0.07$mm, Epoxy $Dies^{(R)}$and increased in the order of $Suprastone^{(R)}$, Die $Keen^{(R)}$. There was significant difference between $Fuji-rock^{(R)}$ and Die Keen(p<0.05). 6. In this experiment, Epoxy $Dies^{(R)}$ showed mean contraction in every calculation area. And when reconstruction cross arch restorations it is thought that distortion should be considered in every cast material.