• Journal of the Korean Society for Precision Engineering
• /
• v.27 no.11
• /
• pp.57-62
• /
• 2010

The transmission case has bearing loads, The case should be designed with more stiffness and lightweight under high external loads, In this study, we performed FEA(Finite Element Analysis) for the transmission case and performed topology optimization base on the results of FEA. We performed topology optimization with the control of the shape size which is the results of topology optimization and suggested the shaped of the transmission case of topology optimization.

• Proceedings of the KIEE Conference
• /
• 1998.11a
• /
• pp.308-310
• /
• 1998

In this paper, cost of FACTS devices and that of conventional 345kV transmission devices that transmit scheduled amount of electricity from one point to other point for thirty years is calculated and compared to each other. In case of long distant transmission, cost of FACTS devices is smaller compared to that of conventional 345kV transmission devices, and in case of short distant transmission cost of FACTS devices is bigger than that of conventional transmission devices.

• Proceedings of the KIEE Conference
• /
• 1999.11b
• /
• pp.83-85
• /
• 1999

Recently, a rapid increase of electricity demands have made Transmission & Substation device large-sized. complicated and diverse. Moreover, a rising level of customer's requirement and high growth of industry increase the reliability of electricity service. Therefore on the basis of the case study on the occurrence of fault, the prevention of defects for each device and the analyzing of the outbreak and prevention of systematic breakdown in Sin-Incheon Power Transmission Branch Office, this paper presents some important matters and suggests the method of improvement in design, construction, maintenance, and repairing the Transmission & Substation device.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2002.05a
• /
• pp.1228-1233
• /
• 2002

This study is aimed to evaluate a tunneling effect in association with the measurement of sound transmission loss. Based on the formulation for sound transmission loss of a finite panel in the presence of tunnel, variations of the sound transmission loss with parameters such as the location of panel and tunnel depth are investigated. It can be seen that differences in the sound transmission loss are quite evident below coincidence frequency and the sound transmission loss greatly depends on panel location in the tunnel. In comparison with the case without a tunnel, maximum difference occurs in the case where the panel is placed on the center of the tunnel and the flushing with the end of the tunnel gives the better estimation of transmission loss.

• Proceedings of the KIEE Conference
• /
• 1997.07c
• /
• pp.1041-1043
• /
• 1997

When a new transmission line is planned to construct, the system voltage and the conductor size of the transmission line should be decided by both economical and technical point of view. This paper presents a methodology to determine the optimal voltage for upgrading the transmission system voltage of existing the extra high voltage grid network by meeting the requirements of the transmission cost minimization as well as technical constraints of thermal limit and stability limit in the transmission line. As a case study, calculated are optimal voltages versus distance and capacity of a practically applicable transmission line with 4 bundles 2 circuits. By this study 400kV was selected as the next higher voltage for the existing 220kV Libyan grid network.

• Journal of Preventive Medicine and Public Health
• /
• v.42 no.1
• /
• pp.1-4
• /
• 2009

Objectives : Isolated cleft lip with or without cleft palate(CL/P) is among the most common human birth defects, with a prevalence of approximately 1 in 700 live births. The B-Cell Leukemia/lymphoma 3(BCL3) gene has been suggested as a candidate gene for CL/P based on association and linkage studies in some populations. This study tests for an association between markers in BCL3 and isolated, non-syndromic CL/P using a case-parent trio design, while considering parent-of-origin effects. Methods : Forty case-parent trios were genotyped for two single nucleotide polymorphisms(SNPs) in the BCL3 gene. We performed a transmission disequilibrium test(TDT) on individual SNPs, and the FAMHAP package was used to estimate haplotype frequencies and to test for excess transmission of multi-SNP haplotypes. Results : The odds ratio for transmission of the minor allele, OR(transmission), was significant for SNP rs8100239(OR=3.50, p=0.004) and rs2965169(OR=2.08, p=0.027) when parent-of-origin was not considered. Parentspecific TDT revealed that SNP rs8100239 showed excess maternal transmission. Analysis of haplotypes of rs2965169 and rs8100239 also suggested excess maternal transmission. Conclusions : BCL3 appears to influence risk of CL/P through a parent-of-origin effect with excess maternal transmission.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2002.11a
• /
• pp.317.2-317
• /
• 2002

Transmission loss of KHST passenger vehicle was calculated using measured acoustic data: In order to verify the transmission loss results for KHST case, similar experiment was carried out in laboratory condition, which result was compared those by geometric acoustic method. The computational results shows good agreement with the transmission loss magnitude from experiments. This paper also mentions items to obtain more accurate transmission loss values, i. e. how to assure reverberant field condition, the selection of source speaker' location.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.53 no.1
• /
• pp.43-55
• /
• 2004

This paper presents a study on evaluating the reliability indices considering a transmission system. Because successful operation of electric power under the deregulated electricity market depends on transmission system reliability management, quantity evaluation of transmission system reliability is very important. This paper introduces features and operation modes of the Transmission Reliability Evaluation for Large-Scale Systems(TRELSS) Version 6.0, a commercial program made in EPRI, and TranRel-I V3.2, a educational program made in GSNU(GyeongSang National University) for assessing reliability indices of composite power system. The packages access not only bulk but also bus indices for reliability evaluation of composite powers system. The practicality, effectiveness and future works of this methodology are illustrated by demonstrations of two case studies of modified IEEE 25 buses reliability test system using TRELSS and TranRel-I and a brief case study for the KEPCO size system using TranRel-II made in GSNU.

• KEPCO Journal on Electric Power and Energy
• /
• v.8 no.2
• /
• pp.55-59
• /
• 2022

This paper introduce Renewable Energy forecasting technology, which is a part of renewable management system. Then, calculation method of dedicated transmission line's meteorological data to forecast renewable energy is suggested. As the case of dedicated transmission line, there is only power output data combined the number of renewable plants' output that acquired from circuit breakers. So it is need to calculate meteorological data for dedicated transmission line that matched combined power output data. this paper suggests two calculation method. First method is select the plant has the largest capacity, and use it's meteorological data as line meteorological data. Second method is average with weight that given according to plants' capacity. In case study, suggested methods are applied to real data. Then use calculated data to Renewable forecasting and analyze the forecasting results.

• KIEE International Transactions on Electrophysics and Applications
• /
• v.5C no.1
• /
• pp.8-13
• /
• 2005

In order to analyze the properties of domestically produced 36,000lb porcelain insulators by change of the alumina addition to raw materials, 36000lb ball socket type suspension insulators that were manufactured in 1989, 1995 and 2001 were removed from transmission lines and an experiment was performed. The results indicated that 8 [wt.%] alumina, which influences the mechanical properties and arc resistance properties in the case of insulators that were manufactured in 1989 was contained, and the relative density and the fracture toughness of insulators appeared by 94.2% and 1.4 [MpaㆍM/sup 1/2/], respectively. However, 12 [wt.%] alumina was contained in the case of insulators that were manufactured in 1995, and the relative density and the fracture toughness of insulators appeared preferably lower by 92% and 1.3 [MpaㆍM/sup 1/2/], respectively. The greatest amount of alumina was contained by 17 [wt.%] in the case of insulators that were manufactured in 2001. It was confirmed that the electrical and mechanical characteristics such as the relative density and the fracture toughness appeared remarkably by 96% and 1.7 [Mpaㆍm/sup 1/2/], respectively.