• Journal of applied mathematics & informatics
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• v.7 no.3
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• pp.995-1004
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• 2000

In this paper we shall give a slight generalization of J. Vukman's Theorem. And show from the result that the image of a continuous linear Jordan derivation on a noncommutative Banach algebra A is contained in the radical under the condition [D(x),x]E(x) ${\in}$ rad(A) for all $x{\in}A$ . And we show some properties of the derivations on noncommutative Banach algebras.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.766-771
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• 2000

This study is mainly concerned with friction and wear properties for the piston ring of non-lubricating air compressor which made of PTFE-polyimide composites. At the PTFE and polyimide alone mixture specimens, PTFE80%-polyimide20%, which shows the lowest men friction coefficient and specific wear rate at 0.94m/s sliding speed. At each of carbon, copper and oxide lopper mixed with PTFE80%-polyimide20%. In case of copper10%, at 0.94m/s sliding speed, the mean friction coefficient shows 0.087, which is the lowest value in all specimens. In case of the specific wear rate, copper30% specimen shows the lowest value of $2.537E-5(mm^3/Nm)$ in all specimens.

• Journal of the Korean Mathematical Society
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• v.36 no.4
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• pp.747-756
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• 1999

In ring theory it is well-known that a ring R is (von Neumann) regular if and only if all right R-modules are flat. But the analogous statement for this result does not hold for a monoid S. Hence, in sense of S-acts, Liu (]10]) showed that, as a weak analogue of this result, a monoid S is regular if and only if all left S-acts satisfying condition (E) ([6]) are flat. Moreover, Bulmann-Fleming ([6]) showed that x is a regular element of a monoid S iff the cyclic right S-act S/p(x, x2) is flat. In this paper, we show that the analogue of this result can be held for automata and them characterize regular semigroups by flat automata.

• YAKHAK HOEJI
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• v.45 no.2
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• pp.140-146
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• 2001

The synthesis of new 6-exomethylene penams with triazole ring for $\beta$-lactamase inhibitor was described. The 6,6-dibromopenam 6 was treated with $CH_3$MgBr and carbaldehyde 5 to afford the 6-bromo-6-(1-hydroxy-1-methyl)penicillanate 7, which was reacted with acetic anhydride to give acetoxy compound 8. The deacetoxybromination of 8 with zinc and acetic acid gave 6-exomethylenepenams, Z-isomer 9 and E-isomer 10, which were oxidized to sulfones 11 and 12 by m-CPBA. The p-methoxybenzyl compounds 9~12 were deprotected by AIC1$_3$and neutralized to give the sodium salts 13~16.

• YAKHAK HOEJI
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• v.46 no.5
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• pp.307-312
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• 2002

The synthesis of new 6-exomethylene penams with benzothiazole ring was described. The 6,6-dibromopenam 5 was treated with $CH_3$MgBr and carbaldehyde 4 to afford the 6-bromo-6-(1-hydroxy-1-methyl)penicillanate 6, which was reacted with acetic anhydride to give acetoxy compound 7. The deacetobromination of acetoxy compound 7 with zinc and acetic acid gave 6-exomethylene penams, Z-isomer 8 and E-isomer 9, which was oxidized to sulfones 10 by m-CPBA. The p-methoxybenzyl compounds 6~10 were deprotected by AlCl$_3$ and neutralized to give the sodium salts 11~15.

• Bulletin of the Korean Chemical Society
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• v.29 no.4
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• pp.827-832
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• 2008

A new diarylethene compound with donor and acceptor substituent was synthesized from 2,3-bis(2-methylbenzo[b]thiophene-3-yl)hexafluorocyclopentene (BTF) over 5 steps. The donor-acceptor structured BTF compound (TBTFE) showed spectral change to a longer wavelength through photochromism with a high cyclization quantum yield (0.56). The 3,4-ethylenedioxythiophene (T) and carboethoxy (E) groups directly connected to BTF unit promoted electrical change accompanied with the photoisomerization of the BTF unit. Photo-induced electrical switching was achieved from a photocell containing TBTFE doped polymer film, which showed reversible and stable current change over repeated cycles by the alternative UV/Vis irradiation, as estimated by the I-V plot.

• Proceedings of the IEEK Conference
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• 2003.11c
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• pp.24-27
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• 2003

Radiofrequency ablation (RFA) as one of the microwave hyperthermia is becoming the treatment of choice for small but inoperable tumors of the liver. In this paper, we designed the applicator composed of semi-rigid coaxial cable antenna with a ring slot for RFA. To optimize the maximum output of radiation with omni direction at 2450 ㎒, we simulated the applicator using Electromagnetic simulation program and analyzed the return loss and the electric field E$\_$tot/ at the near-field region between the simulation results and measurement results. As a result, we obtained the return loss of -29.786 dB at 2450 ㎒ when the applicator was placed between two blocks of a pig's liver, and the measurement results agreed with the simulation results well. Therefore, this applicator using semi-rigid coaxial cable antenna with a ring slot can be used very usefully as the applicator for RFA.

• Animal cells and systems
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• v.9 no.4
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• pp.181-190
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• 2005

BIRPs (BIR containing Proteins) which contain one to three BIR domains constitute a highly conserved family from yeast to human. BIR domains mediate the interaction of BIRPs with various other proteins. Some of the members acquire a Ring domain which acts as an E3 ubiquitin ligase. The first member of BIRPs identified in the baculovirus was found as an inhibitor of apoptosis and most of the family members in the other species have been recognized to have the same function which bind to and inhibit caspases, thereby suppresses apoptotic cell death. But an increasing number of evidences indicate that BIRPs are involved in various cellular events such as cell division, control of cell cycle, signal transduction, cell migration, innate immunity as well as regulation of apoptosis. In this review, we summarize the structural and functional features of the BIRPs, especially focus on the various functions of BIRPs unrelated to regulation of apoptosis by the recent findings.

• Electrical & Electronic Materials
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• v.9 no.1
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• pp.59-66
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• 1996

Polyimides containing cyclobutane ring in main chain is known to be thermally stable and able to be developed in organic solvents after photolysis with 254 nm UV light. This type of polyimides can be used as promising positive photoresist in VLSI fabrication process. In the current VLSI process, photoresist films are formed by spin coating. The film thickness is more than several hundred nano meters. It seems that there is room for improvement of film coating process by introducing Langmuir Blodgett technique. Thereby ultra thin film photoresist can be formed, and higher density of integration in VLSI be achieved. In the present work, depositing procedure of LB films of this polyimide was investigated. LB film thickness was measured by ellipsometry to evaluate deposited film status. Chemical imidization procedure was studied to avoid several problems in thermal imidization. The pattern of submicron dimension has successfully formed on LB film of 8nm thick, which found showing good contrast.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.7
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• pp.152-157
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• 2014

Pro-program function of Pro/E has been utilized to expedite the design process of bellows. Design parameters selected for bellows design are manipulated to obtain the shapes user specified. User-oriented function may automate the bellows design process and this function may enable to reduce the design time remarkably. Generated bellows solid model has been applied to study of design sensitivity and optimum design. Among the selected design parameters, thickness of bellows affects system response most. Control-ring installed bellows may reduce the stress and prove to be an effective element for heavy load. The finite element analysis results combined with 3D model generated by pro-program may provide the feasible design directions to the bellows designer.