• Proceedings of the KIEE Conference
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• 2006.11a
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• pp.129-131
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• 2006

KEPCO constructed the first 765kV 2 circuit transmission line in the world with its home grown technologies. Through this 765kV transmission system project, KEPCO accumulated experience and technologies related to the 765 kV power system. Based on the successful completion of the 765kV transmission project, KEPCO is conducting overseas business by using its abundant experience and know-how. In particular, KEPCO developed the training course for power system, called the ATT (Advanced Transmission Technology) training courses for overseas business, especially for developing countries. Therefore, KEPCO developed the "Transmission line design system for overseas projects". This system supports the calculation of wind pressure load, tower design, wire selection, insulation design, etc. by applying the meteorological data of foreign countries and design standards. And this system is applied to the training program so that the trainees can design the optimal transmission line for their own countries.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.452-453
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• 2008

본 논문에서는 송전철탑에 작용하는 설계하중으로서 [송전철탑 설계풍속에 관한 연구]에 근거하여 1987년 6월 제정된 지역별설계 풍하중기준의 개정을 위한 연구결과를 수록하였다. 당시 제정된 송전설계기준은 이전에 전국적으로 통일시켜 적용되던 풍속압($76kg/m^2$)을 지역별 풍속을 구분하여 그 차이에 따라 I, II, III, 지역 및 울릉도로 구분하여 차등 적용하였으며, 본 연구에서는 국내 기상청이 생긴 이래 2005년까지 누적된 기상 DB의 분석을 통하여 최근의 기상 현상을 반영한 보다 현실적인 설계기준 개정과정을 수록하였다. 본 논문에서는 1980년대 후반부터 약 20년간의 기상청의 풍향, 풍속자료를 추가로 확보하여 이를 분석하고 재현기간을 반영한 지역별 설계하중을 재산정하여 최근의 기상자료를 포함하여 보다 정확한 분석을 도모하고, 사회 환경의 급변함에 따라 우려되는 기상이변 등을 고려한 안전성과 경제성이 향상된 설계기준의 산정과정을 고찰하고자 한다.

• Journal of the Korean Professional Engineers Association
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• v.15 no.4
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• pp.12-24
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• 1982

East Parts of Bangladesh have been benifited by low cost energy generated by domestic natural gas but West parts where energy generated by imported fuel. Bangladesh Government authority has very much concerned to transmit the low cost electricity to the West from the East for past several years. To solve such concerns, cross-country 230kv double circuits Power transmission line was proposed, however there was a big obstacle for the realization of this line to cross the Jamuna river which has 12 km long width with a deep muddy river bed. A consultant engineering firm named Merz-Mclellan anyway finalized this plan and a world-wide bid was announced on June 31, 1979. Due to the expected difficulty to construct the towers on sea like area, only three construction groups have participated. including a Korean joint venture organization of Samsung-Korean Developement corporation-Kolon Electric Machinery company. After 3 months bid evaluation, contract was awarded to Korean Consosium and KEM Co was in charge of designing steel towers with anchor bolts and base plates beside to electrical engineering field. Then KEM Co have faced and over-comed many unenpected technical difficulties such as forced eccentricity joint on base plate, distorsion issue of 60mm thick plates welding, threading anchor bolts, tad heat treatment of some anchor bolts, disagreement from Consultant Engineer on multiplying factor of leg stresses for 45$^{\circ}$ wind and on reducing O.L.F for wind loads on cables for such 1220km long spans. After spending two years long period for designing and engineering towers, base plates, and anchor bolts, first shipment of tower was finally realized on Nov. 8, 1981 and on the other hand KDD has proceeded concrete caisson work on schedule at Jamuna river site and expected to complete tower erection and stringing of cables within this year of 1982 which was original completion target.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.719-720
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• 2007

Korea, for the first time in the world, constructed 765 kV double circuits transmission lines, which has 3 phases and 6 bundles with vertical arrangement using steel pipes in 1998. Also in 2002, we developed 765kV outdoor full GIS substation with self-developed technology. KEPCO accumulated a wealth of technologies for 765kV system construction and operation, and are listed 5th in technology field in the world. With this advanced technologies, we are developing oversea business. We started with a projects, 'Development Study on the Power System Network Analysis in Myanmar' in 2001, and continued the project to transmission design, consulting for transmission technology including the education of foreign trainees in south-east and middle east asia. Currently, 12 overseas businesses including 330kV transmission system consulting in Ghana, are in progress. In 2007, beginning with 750 kV transmission consulting in China, we are operating ATT(Advanced Transmission Technology) training program, which educate engineers of government and utilities company from China, Myanmar, Cambodia, Laos and Cambodia. However, for the successful development study on the power system, design of the power system and the training service, it is essential to standardize load design criteria in consideration of temperature, wind speed, air pressure and density, etc. of the other countries. Therefore, in this paper, standardized load design criteria for Cambodia, Laos, Myanmar is explained.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.11
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• pp.78-83
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• 2010

Since a tower crane is too high for a worker to ascend and by the wind in the high altitude, the possibility of a safety accident is very high, a lift assist is used. In this study, the hydraulic fall prevention device using the pressure generation device by Seok, et al. was developed. For this, the effects on the fall prevention performances of factors such as gear clearance, oil viscosity, rotative velocity and so on were evaluated by the analysis of fluid flow using FEM and the prototype was producted and a function test was performed.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.632-634
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• 2005

Korea takes part in overseas business by use of accumulated advanced technology through construction of the worlds first 765kV double circuit transmission system designed with pure local technology. 'Development Study on the Power System Network Analysis in Myanmar' was received in the year 2001 and was completed in the year 2002. The following project,'Feasibility Study and Basic Designs for the 500kV Transmission System in Myanmar' has been in progress since January, 2004. With regards to this project the master plan for the Myanmar long term power system was submitted in January 2005, and now the basic designs for the 500kV transmission system construction are in progress. Technical data for the design of the transmission line is calculated using a very complex numerical formula that is almost impossible to be completed by hand. So the transmission technical calculation system was developed to calculate and support Myanmar technical data for the design of transmission line with respect to factors such as wind prossure load, tower design data conductor design data and insulator design data on the basis of weather conditions for the Myamar transmission line design area of the Myanmar 500kV trans- mission line construction basic design.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.764-767
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• 2010

The high enthalpy plasma research center in Chonbuk national university is under construction for MW class plasma wind tunnel. Four types of plasma equipment will be installed in the research center. The equipments are 1set of 0.4 MW class enhanced Huels type plasma equipment, 1 set of 2.4 MW class enhanced Huels type plasma equipment, 1 set of 60 kW RF plasma equipment and 1 set of 200 kW RF plasma equipment. And electrical, water and gas utilities to assistant plasma equipments are under construction. The research center consists of experiment building, research building, power supply building, air supply building, cooling tower foundation.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.23 no.4
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• pp.153-178
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• 2018

Most operational uses of wind speed data require measurements at, or estimates generated for, the reference height of 10 m above mean sea level (AMSL). On the Ieodo Ocean Research Station (IORS), wind speed is measured by instruments installed on the lighthouse tower of the roof deck at 42.3 m AMSL. This preliminary study indicates how these data can best be converted into synthetic 10 m wind speed data for operational uses via the Korea Hydrographic and Oceanographic Agency (KHOA) website. We tested three well-known conventional empirical neutral wind profile formulas (a power law (PL); a drag coefficient based logarithmic law (DCLL); and a roughness height based logarithmic law (RHLL)), and compared their results to those generated using a well-known, highly tested and validated logarithmic model (LMS) with a stability function (${\psi}_{\nu}$), to assess the potential use of each method for accurately synthesizing reference level wind speeds. From these experiments, we conclude that the reliable LMS technique and the RHLL technique are both useful for generating reference wind speed data from IORS observations, since these methods produced very similar results: comparisons between the RHLL and the LMS results showed relatively small bias values ($-0.001m\;s^{-1}$) and Root Mean Square Deviations (RMSD, $0.122m\;s^{-1}$). We also compared the synthetic wind speed data generated using each of the four neutral wind profile formulas under examination with Advanced SCATterometer (ASCAT) data. Comparisons revealed that the 'LMS without ${\psi}_{\nu}^{\prime}$ produced the best results, with only $0.191m\;s^{-1}$ of bias and $1.111m\;s^{-1}$ of RMSD. As well as comparing these four different approaches, we also explored potential refinements that could be applied within or through each approach. Firstly, we tested the effect of tidal variations in sea level height on wind speed calculations, through comparison of results generated with and without the adjustment of sea level heights for tidal effects. Tidal adjustment of the sea levels used in reference wind speed calculations resulted in remarkably small bias (<$0.0001m\;s^{-1}$) and RMSD (<$0.012m\;s^{-1}$) values when compared to calculations performed without adjustment, indicating that this tidal effect can be ignored for the purposes of IORS reference wind speed estimates. We also estimated surface roughness heights ($z_0$) based on RHLL and LMS calculations in order to explore the best parameterization of this factor, with results leading to our recommendation of a new $z_0$ parameterization derived from observed wind speed data. Lastly, we suggest the necessity of including a suitable, experimentally derived, surface drag coefficient and $z_0$ formulas within conventional wind profile formulas for situations characterized by strong wind (${\geq}33m\;s^{-1}$) conditions, since without this inclusion the wind adjustment approaches used in this study are only optimal for wind speeds ${\leq}25m\;s^{-1}$.

• Journal of Digital Convergence
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• v.19 no.9
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• pp.217-228
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• 2021

The purpose of this study is to analyze drum performance techniques, focusing on the representative artists of funk music, who had a revival starting in the 1970s. The purpose of this study is to analyze the creativity shown in David Garibaldi's playing technique, which had a great influence on drum majors with his funk drum playing technique. As a research method, 'James Brown', 'Earth, Wind & Fire' and 'Tower of Power' with David Garibaldi as drummer were selected as representative bands. For the study period, the drum performance was examined by selecting two representative songs from among the songs released between 1965 and 1975, when the development of the corresponding funk music began. David Garibaldi's creative performance in this study is as follows. First, we tried to create a new rhythm in the form of changing the beat or resting the beat out of the frame of contemporary drum performance. Second, the 'Paradiddle', 'Accent', and 'Swiss Army triplet' rudiment techniques were applied to the entire drum kit, bringing innovation to the rhythm. Third, the samba pattern of Latin rhythm and the form of 'Afro-Cuban' were grafted onto funk music. Fourth, the idea of Unison Rhythm obtained from the structure of Latin music was applied to funk music. Based on this study, it is hoped that research on drum performance techniques of various genres will be conducted.