• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.11
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• pp.2285-2291
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• 2011

In this paper, H.264 high profile intra frame encoder, which integrates intra prediction, context-based adaptive variable length coding(CAVLC), and DDR2 memory control module, is proposed. The designed encoder can be operated in 440 cycle for one-macroblock. In order to verify the encoder function, we developed the reference C from JM 13.2 and verified the developed hardware using test vector generated by reference C. The designed encoder is verified in the FPGA (field programmable gate array) with operating frequency of 200 MHz for DMA (direct memory access), operating frequency of 50 MHz of Encoder module, and 25 MHz for VIM(video input module). The number of LUT is 43099, which is about 20 % of Virtex 5 XC5VLX330.

• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.663-669
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• 2012

The nucleophilic substitution reactions of dibutyl chlorophosphate (3) with substituted anilines ($XC_6H_4NH_2$) and deuterated anilines ($XC_6H_4ND_2$) are investigated kinetically in acetonitrile at $55.0^{\circ}C$. The obtained deuterium kinetic isotope effects (DKIEs; kH/kD) are secondary inverse ($k_H/k_D$ = 0.86-0.97) with the strongly basic anilines while primary normal ($k_H/k_D$ = 1.04-1.10) with the weakly basic anilines. The DKIEs, steric effects of the two ligands, activation parameters, cross-interaction constants, variation trends of the kH/kD values with X, and mechanism are discussed for the anilinolyses of the nine ($R_1O$)($R_2O$)P(=O)Cl-type chlorophosphates. A concerted mechanism is proposed with a backside nucleophilic attack transition state for the strongly basic anilines and with a frontside attack involving a hydrogen-bonded four-center-type transition state for the weakly basic anilines on the basis of the magnitudes, secondary inverse and primary normal, and variation trends of the $k_H/k_D$ values with X.

• Bulletin of the Korean Chemical Society
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• v.25 no.4
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• pp.557-559
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• 2004

The aminolyses of anilinothioethers $(C_6H_5N(CH_3)CH_2SC_6H_4Z)$ in acetonitrile with benzylamines $(XC_6H_4CH_2NH_2)$ have been investigated. The rates are much lower in acetonitrile than in methanol (with aniline). The Bronsted ${\beta}_X$ values are similar but ${\beta}_Z$ values are smaller compared to those for the reactions in MeOH with anilines. The large negative ${\rho}_{XZ}({\cong}-0.8$, after correction for fall-off) value is interpreted to indicate a frontside attack $S_N2$ mechanism, in which the two oppositely changed reaction centers in the TS, $-N^{{\delta}+}{\cdots}S^{{\delta}-}-$, are in close vicinity increasing the interaction between nucleophile and leaving group. The inverse secondary kinetic isotope effects ($k_H/k_D$ < 1.0) are observed with deuterated benzylamines $(XC_6H_4CH_2ND_2)$.

• Bulletin of the Korean Chemical Society
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• v.33 no.3
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• pp.1037-1041
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• 2012

The nucleophilic substitution reactions of (2R,4R,5S)-(+)-2-chloro-3,4-dimethyl-5-phenyl-1,3,2-oxazaphospholidine 2-sulfide (3) with substituted anilines ($XC_6H_4NH_2$) and deuterated anilines ($XC_6H_4ND_2$) are investigated kinetically in acetonitrile at $5.0^{\circ}C$. The anilinolysis rate of 3 involving a cyclic five-membered ring is considerably fast because of small negative value of the entropy of activation (${\Delta}S^\neq=-2cal\;mol^{-1}\;K^{-1}$) over considerably unfavorable enthalpy of activation (${\Delta}H^\neq=18.0\;kcal\;mol^{-1}$). Great enthalpy and small negative entropy of activation are ascribed to sterically congested transition state (TS) and bulk solvent structure breaking in the TS. A concerted $S_N2$ mechanism with a backside nucleophilic attack is proposed on the basis of the secondary inverse deuterium kinetic isotope effects, $k_H/k_D$ < 1.

• Bulletin of the Korean Chemical Society
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• v.23 no.2
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• pp.221-224
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• 2002

Nucleophilic addition reactions of benzylamines (BA; $XC_6H_4CH_2NH_2$) to ethyl-${\alpha}$-cyanocinnamates (ECC;$YC_6H_4CH$=C(CN)COOEt) have been investigated in acetonitrile at $30.0^{\circ}C$. The rate is first order with respect to BA and ECC. The rate is slower than that expected from the additive effect of ${\sigma}^-$ or $R^-$ for the activating groups (CN and COOEt). Natural. bond orbital ${\pi}^{\ast}_{c=c}$ calculations show that the contribution of COOEt group may not be fully effective despite the coplanar molecular structure. The selectivity parameters including the cross-interaction constant (${\rho}_{xy}$ = -0.22) indicate that the addition occurs in a single step. The kinetic isotope effects ($k_H/k_D$=2.5-2.8) involving deuterated BA ($XC_6H_4CH_2ND_2$) nucleophiles and activation parameters (${\Delta}H^{\neq}=4{\sim}6\;kcal\;mol^{-1};{\Delta}S^{\neq}=-45{\sim}-52\;e.u.$) suggest a cyclic transition state in which N-$C_{\alpha}$ and H-$C_{\beta}$ bonds are formed concurrently.

• Transactions of the Korean hydrogen and new energy society
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• v.2 no.1
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• pp.57-67
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• 1990

This study is proposed to investigate the effect of electrode preparation method for Alkaline Fuel Cell using NaOH as an electrolyte on the Fuel Cell performance. The materials used for the preparation of electrode are Pt and Ag on Vulcan XC-72. Surface area of Vulcan XC-72 have different values according to the pretreatment conditions and the dispersion of Pt is dependent on the impregnation Particle size of Pt impregnated on unpretreated carbon was observed to be $20{\sim}40{\AA}$ and that on pretreated carbon in $N_2$ stream at $950^{\circ}C$ was found to be finely dispersed less then $15{\AA}$. The electrode performance was affected by the particle size of metals and operating temperature. It was revealed from this study that the optimum particle size about $30{\AA}$ and optimum temperature range is between $90{\sim}100^{\circ}C$.

• Bulletin of the Korean Chemical Society
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• v.32 no.6
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• pp.1997-2002
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• 2011

The nucleophilic substitution reactions of dicyclohexyl phosphinic chloride [3; $cHex_2$P(=O)Cl] with substituted anilines ($XC_6H_4NH_2$) and deuterated anilines ($XC_6H_4ND_2$) are investigated kinetically in acetonitrile at 60.0 $^{\circ}C$. The anilinolysis rate is too slow to be rationalized by the stereoelectronic effects. The rate is contrary to expectations for the electronic influence of the two ligands and exhibits exceptionally great negative deviation from the Taft's eq. The deuterium kinetic isotope effects (DKIEs) involving deuterated anilines invariably change from primary normal ($k_H/k_D$ > 1; max $k_H/k_D$ = 1.10 with X = 4-MeO) with the strongly basic anilines (X = 4-MeO, 4-Me, 3-Me) to secondary inverse ($k_H/k_D$ < 1; min $k_H/k_D$ = 0.673 with X = 3-Cl) with the weakly basic anilines (X = H, 4-F, 4-Cl, 3-Cl). A concerted $S_N2$ mechanism is proposed on the basis of both secondary inverse and primary normal DKIEs. The obtained DKIEs imply that the fraction of a frontside attack increases as the aniline becomes more basic. A hydrogen-bonded, four-center-type transition state is suggested for a frontside attack, while the trigonal bipyramidal pentacoordinate transition state is suggested for a backside attack.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.3C
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• pp.306-313
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• 2007

In this paper, we efficiently implemented turbo code algorithm in FPGA H/W(hardware) resource. The used turbo code algorithm has the characteristics; the size of constraint is 3, encoder type is 1/3, the size of random interleaver is 2048. The proposed H/W consists of MAP block for calculating alpha and delta using delta value, storing buffer for each value, multiplier for calculating lamda, and lamda buffer. The proposed algorithm and H/W architecture was verified by C++ language and was designed by VHDL. Finally the designed H/W was programmed into FPGA and tested in wireless communication environment for field availability. The target FPGA of the implemented H/W is VERTEX4 XC4VFX12-12-SF363 and it is stably operated in 131.533MHz clock frequency (7.603ns).

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3355-3360
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• 2011

The nucleophilic substitution reactions of 1,2-phenylene phosphorochloridate (1) with substituted anilines ($XC_6H_4NH_2$) and deuterated anilines ($XC_6H_4ND_2$) are investigated kinetically in acetonitrile at $-15.0^{\circ}C$. The studied substrate of 1,2-phenylene phosphorochloridate is cyclic five-membered ring of phosphorus ester, and the anilinolysis rate of 1 is much faster than its acyclic analogue (4: ethyl phenyl chlorophosphate) because of extremely small magnitude of the entropy of activation of 1 compared to 4. The Hammett and Bronsted plots exhibit biphasic concave upwards for substituent X variations in the nucleophiles with a break point at X = 3-Me. The values of deuterium kinetic isotope effects (DKIEs; $k_H/k_D$) change from secondary inverse ($k_H/k_D$ < 1) with the strongly basic anilines to primary normal ($k_H/k_D$ > 1) with the weakly basic anilines. The secondary inverse with the strongly basic anilines and primary normal DKIEs with the weakly basic anilines are rationalized by the transition state (TS) variation from a predominant backside attack to a predominant frontside attack, in which the reaction mechanism is a concerted $S_N2$ pathway. The primary normal DKIEs are substantiated by a hydrogen bonded, four-center-type TS.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.05a
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• pp.404-406
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• 2015

This paper describes a small-area hardware implementation of the block cipher algorithm CLEFIA-128 which supports for 128-bit master key. A compact structure using single data processing block is adopted, which shares hardware resources for round transformation and the generation of intermediate values for round key scheduling. In addition, data processing and key scheduling blocks are simplified by utilizing a modified GFN(generalized Feistel network) and key scheduling scheme. The CLEFIA-128 crypto-processor is verified by FPGA implementation. It consumes 823 slices of Virtex5 XC5VSX50T device and the estimated throughput is about 105 Mbps with 145 MHz clock frequency.