• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.6
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• pp.556-565
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• 1991

Using the WDZ decomposition algorithm, a parallel algorithm is presented for solving the linear system Ax=b which has an nxn nonsingular tridiagonal matrix. For implementing this algorithm a CAM systolic arrary is proposed, and each processing element of this array has its own CAM to store the nonzero elements of the tridiagonal matrix. In order to evaluate this array the algorithm presented is compared to theis compared to the LU decomposition algorithm. It is found that the execution time of the algorithm presented is reduced to about 1/4 than that of the LU decomposition algorithm. If each computation process step can be dome in one time unit, the system of eqations is solved in a systolic fashion without central control is obtained in 2n+1 time steps.

• Bulletin of the Korean Chemical Society
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• v.26 no.12
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• pp.1946-1952
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• 2005

New group 15 organometallic compounds, M$(phenanthrenyl)_3$ (M = P (1), Sb (2), Bi (3)) have been prepared from the reactions of 9-phenanthrenyllithium with $MCl_3$. A reaction of 9-(diphenylphosphino)phenanthrene with 2,6-diisopropylphenyl azide led to the formation of (phenanthrenyl)${(Ph)}_2P$=N-(2,6-$^iPr_2C_6H_3$) (4). The crystal structures of 2 and 4 have been determined by single-crystal X-ray diffractions, both of which crystallize with two independent molecules in the asymmetric unit. Compound 2 shows a trigonal pyramidal geometry around the Sb atom with three phenanthrenyl groups being located in a screw-like fashion with an approximately $C_3$ symmetry. A significant amount of CH- -$\pi$ interaction exists between two independent molecules of 4. The phosphorus center possesses a distorted tetrahedral environment with P-N bond lengths of 1.557(3)$\AA$ (P(1) N) and 1.532(3)$\AA$ (P(2)-N), respectively, which are short enough to support a double bond character. One of the most intriguing structural features of 4 is an unusually diminished bond angle of C-N-P, attributable to the hydrogen bonding of N(1)-H(5A) [ca. 2.49$\AA$ between two adjacent molecules in crystal packing. The compounds 1-3 show purple emission both in solution and as films at room temperature with emission maxima ($\lambda_{max}$) at 349, 366, and 386 nm, respectively, attributable to the ligand centered $\pi$ $\rightarrow$ $\pi^\ast$ transition in phenanthrene contributed by the lone pair electrons of the Gp 15 elements. Yet the nature of luminescence observed with 4 differs in that it originates from $\pi$ (diisopropylbenzene)-$\pi^\ast$ (phenanthrene) transitions with the $\rho\pi$contribution from the nitrogen atom. The emission maximum of 4 is red-shifted ranging 350-450 nm due to the internal charge transfer from the phenanthrenyl ring to the N-arylamine group as deduced from the ab initio calculations.

• Journal of the Korean Society of Costume
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• v.18
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• pp.211-223
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• 1992

The results of the researches in the wig and the Boyo are as follows. The wig is to be classified into Bu, Pyun, Chah, Cheh, and kwik, Bu is an ornamental hairpin used by the empress, and it is decorated with Boyo. Pyun is a wig made of braided hair. Chah is made of Bal which is put together by its lenath, and it was also called Picheh or Pisuck. It is made, one by one, of hair of the convicts and the low-class people. 초도 has a meaning of toupee, and it is used to look beautiful with its thick black hair. Kwik is a wig made of hair as if it is weaved out of thread, and it is rounded with a wire. In ancient times, it was also called chah, Pi, or Pi People wore different wigs according to their class and the use, in order of Bu, Pyun, and Chah. There are remains of the Han Dynasty. Boyo, just like the wig, was originally a custom of the northern nomadic tribes which had been introduced to the later Han Dynasty. It is also called Cho Song and has a different meaning from the Boyo attached to a crown before the Han Dynasty. It became much more beautiful in the Which in period. Boyo gained its popularity by the women in Tang Dynasty, which is due to the influence by the customs of the western Ho tribe. The name of hairstyling using wigs in each period, and things such as hair, black thread, lignum, and paper were used as materials. Since the wig had differed according to the disparity in social standing it was prohibited to the general public, but it became in style later on. Wig also becomes popular in central Asia and gained its properity in the Tang Dynasty which is greatly influenced by the western countries. It is said in the records that the kobal Style had been exceedingly in fashion from the Ju to the Chung Dynasty, and the remains of the Han and Song Dynasty were found. times, it was also called chah, Pr, or period, and things such as hair, black thread, lignum, and paper were used as materials. Since the wig had differed according to the disparity in social standing, it was prohibited to the general public, but it became in style later on. Wig also becomes popular in central Asia and gained its prosperity in the Tang Dynasty which is greatly influenced by the western countries. It is said in the records that the kobal Style had been exceedingly in fashion from the Ju to the Chung Dynasty, and the remains of the Han and Song Dynasty were found.