• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.1
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• pp.24-31
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• 2004

Recently, as the marine compressor power is increased, vibration problems on the marine vessel with V/W type reciprocating compressor have been occurred. A research on the balancing of marine V/W type reciprocating compressor has hardly been reported though a number of researches on the balancing of rotating machinery have been conducted. As a V/W type compressor has high capacity with long stroke, compact size and high center of gravity, It is easy to have a vibration problem by a little bit unbalanced force and moment. In this study, calculation methods for balance weight of the V/W type reciprocating compressors, which have different piston weight and asymmetry structure, are formulated. And their reliability were verified by comparing calculated balance weight with the experimental results of the real marine V/W type reciprocating compressors.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.54 no.12
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• pp.515-519
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• 2005

We have developed shell type 765kV transformers for generator step-up. Our research and development for shell type 765kV transformers have been continued since 1990. The shell type 765kV transformers of single phase 3MVA for step-up and 500MVA for power transmission were developed in Dec. 1992 and Oct. 1996, respectively. 204MVA 765kV transformer for generator step-up was also developed with the basis of technique and experience to the present. Total 12 phases of 204MVA 765kV transformers will be delivered at Tangjin thermal power plant by 2006. This paper describes electrical and structural features of the shell type 204MVA 765kV transformer.

• Bulletin of the Society of Naval Architects of Korea
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• v.17 no.2
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• pp.33-42
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• 1980

This paper compared the seakeeping quality of U, V type ships in infinite depth by using the finite element method. From the calculated results, it is found that heaving and pitching motions of V type are comparatively better than those of U type ship in the water of infinite depth and the reversed phenomenon occures in the water of finite depth. And the seakeeping quality of U type is better than V type ship in larger ranges than the nondimensional wave number 2.0.

• Journal of Fisheries and Marine Sciences Education
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• v.26 no.1
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• pp.98-107
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• 2014

As part of a series of studies about improving yellow croaker drift gill net fishing gear and the development of a labor-saving fishing system, we installed a labor-saving-type, five-step-drum net hauler, and a triple-V-type net hauler in 108 Daeheung-ho, a fishing boat which operates drift gill nets for yellow croakers mainly in the sea near Chu-ja Island. Net damage with the labor-saving-type, five-step-drum net hauler is lower than for the triple-V-type net hauler. In addition, there was a reduction in the standard operational crew of two people. The lead time for hauling the labor-saving net was approximately 10% and 19.2% less than for hauling the triple-V-type net hauler and for hauling by hand, respectively. It was found that there were fewer slip in fishing gear and less damage to the wing of the drum as well as less damage to the fish when the labor-saving-type, five-step-drum net hauler was used than when the triple-V-type net hauler was used. In the survey, the lead time for hauling the net was approximately 21.6% and 45.2% more effective than hauling with the triple-V-type net hauler and hauling by hand, respectively. The crew was reduced by approximately 18.2% and 25% than when hauling with the triple-V-type net hauler and hauling by hand, respectively. In addition, cessation of operation and damage to the fish were reduced when compared to the triple-V-type net hauler and hauling by hand.

• Journal of Veterinary Clinics
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• v.14 no.2
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• pp.338-348
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• 1997

The electrocardiographic (ECG) parameters on unipolar precordial chest leads in the normal Korean native goat of 343 heads as to CV$_{6}$LU, CV$_{6}$LL CV$_{6}$RU, CV$_{6}$RL and V10 have been measured with a 3-channel Elertrocardiograph and computed, analysed. All wave types as positive, negatives biphasic and flatting in the P and T waves appeared in all leads but any special wave type was not shown more than 60%. Average amplitudes with the highest frequent rate in P wave were 81.4$\pm$32.0 $\mu $V (52.3%), 59.6$\pm $ 27.5 $\mu $V (50.5 %) of Positive type in leads CV$_{6}$LU and CV$_{6}$LL, and -5fl.5$\pm $22.6 $\mu $V (44.0%) of negative type in leads VIO, and 51.3% and 44% of flatting type in leads CV$_{6}$RU and CV$_{6}$RL, but flatting type of clinic form appeared frequent rate between 53% and 77% in all leads. In T wave, average amplitudes with the highest frequent rate were 265.0$\pm $97.1 $\mu $V (54.0%) and 212.2$\pm $90.7 $\mu $V (57.0%) of positive type in leads CV$_{6}$LL and CV$_{6}$RL, and -252.8$\pm $90.7 $\mu $V (56.6%) of negative in lead V10, but amplitudes of T waves that positive and negative type appeared similarity frequent ra蛇 ware 208.7$\pm $99.7 $\mu $V (42.1%), -159.0$\pm $81.6 (43.8%) in lead CV$_{6}$LU and 153.2$\pm $139.0 $\mu $V (47.3%), -130.0$\pm $81.4 (43.2%) in lead CV$_{6}$RU, Amplitudes of QRS complex wave forms showed the highest frequent rate were 218.2$\pm $96.4 $\mu $V (47.8%), 308.3$\pm $135.2 $\mu $V (46.8 %), 232.8$\pm $126.5 $\mu $V (58.5%) and 225.3$\pm $89.6 $\mu $V (54.9%) of R type in the leeds CV$_{6}$LU, CV$_{6}$LL, CV$_{6}$RU and CV$_{6}$RL, and were -92.5$\pm $79.1 $\mu $V,479.0 $\pm $116.6 $\mu $V (33.2%) and 212.1 $\pm $86.7 $\mu $V (32.8%) of QR and 05 type in the lead V10. These results in the V10, CV$_{6}$RU, CV$_{6}$RL, CV$_{6}$LU, CV$_{6}$LL. may be not starve to purpose of unipolar precordial chest leads.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2006.10a
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• pp.198-201
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• 2006

In this paper, we fabricated drag force type and pressure difference type gas flow sensor with dry etching technology which used Deep RIE(reactive ion etching) and etching stop technology which used SOI(silicon-on-insulator). we fabricated four kinds of sensor, which are cantilever, paddle type, diaphragm, and diaphragm with orifice type. Both cantilever and paddle type flow sensors have similar sensitivity as 0.03mV/V kPa. Sensitivity of the fabricated diaphragm and diaphragm with orifice type sensor were relatively high as about 3.5mV/V kPa, 1.5mV/V kPa respectively.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.799-802
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• 2002

Continuously variable transmission(CVT) mechanisms considered here combine the functions of a K-H-V type differential gear unit and a V-belt type continuously variable unit(CVU). As combining the functions of a K-H-V type differential gear unit and a V-belt type CVU, 24 different mechanisms are presented. Some useful theoretical formula related to speed ratio, power flow and efficiency are derived and analyzed. These mechanisms have many advantages which are the decrease of CVT size, the increase of overall efficiency, the extension of speed ratio range, and the generation of geared neutral.

• Journal of Species Research
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• v.2 no.2
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• pp.191-202
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• 2013

The article provides information on type specimens of 150 taxa of vascular plants from Korea, kept in the Herbarium of the Komarov Botanical Institute of the Russian Academy of Sciences. For all specimens, type category is indicated. Lectotypes for the names of Clematis brachyura Maxim., C. spectabilis Palib., Corydalis wilfordii Regel, Poa viridula Palib., Polygonum marretii H. L$\acute{e}$v., P. sagittatum L. var. hallaisanense H. L$\acute{e}$v., P. taquetii H. L$\acute{e}$v. and P. thunbergii Sieb. et Zucc. var. coreana H. L$\acute{e}$v. were designated. Type specimens examined in this article belong to the taxa described by Russian botanists V.L. Komarov, K.J. Maximovicz and I.V. Palibin, French botanist A.A.H. L$\acute{e}$veill$\acute{e}$ (some with co-author E. Vaniot) and others.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.438-439
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• 2011

Substations in Korea are classified into an outdoor steel structure type, an outdoor GIS(Gas Insulated Switchgear) type, an indoor GIS type, an underground GIS type, and a complex GIS type. Before 1970, substations were built in outdoor steel structure types only. In 1980, an 154kV indoor GIS type substation was built for the first time in Pusan. And the first 345kV indoor GIS type substation, the first 765kV full GIS substation were built in 1984 and in 2002 each. In 1998, 154kV indoor type substations were standardized into regular type and urban type which applied steel frames to structures. In 2002, this was re-standardized into five different types in detail. In 2007, hub substations which had high capacity were built in the region of industrial zone and heavy load areas. And 154kV compact substation was developed and standardized by compacting an indoor GIS type substation in 2009. This paper would present a series of substation type transition and application standards for substation types and facility scales.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.436-437
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• 2011

Before 1970s, 154kV substations in Korea were built in outdoor steel structure types only. In early 1970s, Germany developed GIS and the first indoor GIS type substation was built in Korea in 1980. In 1998, 154kV indoor type substations were standardized into regular type and urban type which applied steel frames to structures. In 2002, this was re-standardized into five different types in detail. In 2009, 154kV compact substation design was developed and standardized and saved about 20% of the construction cost with new technology and methods. Compact substations were classified into three types ; urban type, multi-function type, and regular type. The first urban type compact substation, Jang-ki substation, was built in Kimpo in June, 2010. This paper would present the standard model of 154kV compact substation and the way of improving facilities for the first compact substation.