• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.23 no.7
• /
• pp.1851-1859
• /
• 1998

We summarize the password-based authetication protocol K1P which was introduced in our easlier papers [1,2] and then propose three more extended protocols. These protocols preserve a design concept of K1P, i.e., security and efficiency, and canbe used for various purposes. They are a One-time key K1P, a Client public key K1P, and an Exponential key exchange K1P.

• Proceedings of the KIEE Conference
• /
• 1988.07a
• /
• pp.311-314
• /
• 1988

This paper describes 256k (256K ${\times}$1) CMOS SRAM utilizing 1.2um double-polysilicon and double-metal CMOS process. A typical access time of 16ns with a 30-pF load has been achieved through the use of a block architecture, a new decoder, an unique bit-line scheme and an optimized process. Operating current is 55mA at 40MHz and 15mA at 10MHz. A high-resistive polysilicon load has been used to achieve a standby current of 3uA.

• Proceedings of the KIEE Conference
• /
• 2002.07d
• /
• pp.2182-2184
• /
• 2002

In this paper we describe a prototype Control Rod Control System(CRCS). The CRCS controls the motion of the full length rod drive mechanisms in response to signals from the Reactor Operator and the Reactor Control System. Each mechanism belongs to either Shutdown Banks or Control Banks. The CRCS also provides information regarding the rod motion, rod position, and the status of the Rod Control System. The prototype CRCS will be used to obtain the requirements for detailed design of a full-scale CRCS.

• Proceedings of the KIEE Conference
• /
• 2001.07a
• /
• pp.452-454
• /
• 2001

This paper described the calculation results of lightning flashover rate on the 345kV and 154kV transmission system of KEPCO. The back-flashover rate and shielding failure rate was calculated by FLASH(lightning flashover rate calculation program from IEEE) and KEPRI's own program which is based on the EGM(Electro Geometrical Model) method. The estimated lightning flashover late of 345kV transmission system of double circuit was 1.0 flash per 100km-year, and the lightning flashover rate of 154kV transmission line was 2.0 flash Per 100km-year approximately.

• Proceedings of the KIEE Conference
• /
• 1998.07f
• /
• pp.2027-2029
• /
• 1998

We have developed a compact high frequency switch mode converter (HFSMC) power supply with DC 50 kV output voltage and 10 kW output power. Since the inverter circuit uses 25 kHz rescharging scheme, the current is flowing with t kHz. For the efficient output voltage transform performed a simple design process using the transformer principle and the commercial specification. For the DC 50 kV output, we employed 7 pa windings of secondary coils for the series stac connection of the output with full-bridge rectifi In this paper the design detail and the test re the high frequency transformer together with HFSMC power supply are presented.

• Proceedings of the KIEE Conference
• /
• 1998.07e
• /
• pp.1647-1649
• /
• 1998

This paper describes the power frequency voltage and its countermeasure when a 765 kV transmission line is directly connected to a 345 kV line and operated at 345 kV voltage. The summary of this result is as follows : The western route of 765 kV transmission line doesn't need any countermeasure to reduce the power frequency voltage at the receiving end. The eastern route of 765 kV transmission needs 100 Mvar(3 phase) capacity of shunt reactor at the receiving end to reduce the power frequency voltage. The use of shunt reactors in the 765 kV transmission lines has unexpected problems, one of which is induction of high voltages on a de-energized circuit of two parallel lines. This paper examined the problem of resonance on two parallel transmission circuits in one routes.

• Proceedings of the KIEE Conference
• /
• 1997.07d
• /
• pp.1399-1401
• /
• 1997

The stability of superconducting wires was studied by considering temperature and magnetic field. We measured critical current density of $Nb_3Sn$ tape at 4.2 K, 12 K, 13 K and 14 K in various field. The critical current density at 4.2 K, 6 T is 16.5 times higher than at 12 K, 6 T. We expressed the critical current density as a function of temperature and magnetic field, expanding on work by Hampshire, et al.

• Archives of Pharmacal Research
• /
• v.25 no.5
• /
• pp.681-684
• /
• 2002

This study was undertaken to investigate the hypocholesterolemic activity of Bifidobacteria (B. breve K-110, B. breve K-111, and B. infantis K-525) isolated from a healthy Korean. The administration of B. breve K-110 and K-111 with a high cholesterol diet significantly protected the increase of serum total cholesterol and LDL cholesterol relative to that of a high cholesterol diet alone. Such a diet supplemented with 0.5％ B. breve K-111 decreased serum total cholesterol and LDL cholesterol to 57 and 55％, respectively. The administration of Bifidobacteria also significantly inhibited the lipid-deposited surface in the aorta. The normalizing activity of serum cholesterol level in cholesterolemic rats was accelerated by Bifidobacteria. The normalizing activity of B. breve K-111 on serum cholesterol level was superior to that of B. breve K-110. These results suggest that Bifidobacteria in the human intestine playa role in the prophylactics of arteriosclerosis.

• Journal of Advanced Marine Engineering and Technology
• /
• v.23 no.5
• /
• pp.711-718
• /
• 1999

Current turbulence models including modified $K-{\varepsilon}-{\tau}$ turbulence model do not predict compression effect on turbulence accurately in an internal combustion engine. The $K-{\varepsilon}-{\tau}$ turbulence model was suggested to improve the predictability of compression effect by We et al. In this paper a numeri-cal study was performed to clarify the applicability of the $K-{\varepsilon}-{\tau}$ turbulenc model to the calculation of the in-cylinder flow of an axisymmetric engine. THe results using $K-{\varepsilon}-{\tau}$ turbulence model are compared to those from the modified $K-{\varepsilon}-{\tau}$ turbulence model and experimental data. The mean veloc-ity and rms velocity profiles using $K-{\varepsilon}-{\tau}$ turbulence model showed a better agreement with an experimental data than those of modifid $K-{\varepsilon}-e$ turbulence model.

• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 2004.05a
• /
• pp.63-63
• /
• 2004