• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.1066-1071
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• 2007

This case study refers to turbine-generator with retrofitted turbine rotor. Vibration problem occurring after the retrofit was mainly due to high vibration from exciter side. However, repeated test run and operation during scheduled maintenance caused high vibration from generator bearing, and post-overhaul test run before turbine vibration correction caused oil whip on the bearing. This case study shows how to analyze vibration condition of high turbine generator vibration detected during the post-overhaul test run and vibration condition of offline and online data to reflect it on establishing maintenance schedule and overhaul correction procedure. Vibration data could be acquired during steady load operation or even with varying speed and load. Each data is important for machinery condition evaluation. This case study shows that the vibration data during extreme condition is the key factor in analysis, which helps to find the machinery problem.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.158-158
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• 2008

In general, a wireless communication device has employed a whip antenna or a stubby antenna. Recently, wireless communication device is increasingly employing an embedded antenna, Intenna, for the sake of miniaturization. Further, it may employ both external and embedded antennas. Examples of the embedded antenna include a multi-band monopole antenna, which radiates uniformly in all directions when viewed from above, and a planar inverted F antenna (PIFA), which is a variation of the monopole antenna. However, since the conventional antenna is mounted in a finished state on the mobile communication terminal, there is a limitation of space required for providing the antenna. According to the present study, there is provided an Intenna that is deposited on a front or back case of the mobile communication terminal by a sputtering method. Accordingly, it is possible to overcome a limitation of space required for providing the Intenna and to improve the performance of the Intenna formed on the front or back case of the mobile communication terminal.

• Journal of Environmental Science International
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• v.12 no.2
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• pp.119-124
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• 2003

An effective grafting method for jujube nursery trees was developed to shorten the operation time, improve the percentage of "takes" and shoot emergence, and form the better graft union. Out of 7 grafting methods the splice, modified scion Ono graft and the bark graft showed relatively short operation time during the grafting operation comparing to the modified rootstock Ono graft or the chip budding. Among these methods, the bark graft demonstrated 100% "takes", but the modified scion Ono graft or the standard Ono graft showed 58.3% of "takes". The percentages of the vegetative shoot emergence were 100% fir the bark graft, 70% f3r the modified scion Ono graft and lower emergence percent for the rest grafting methods. The union tissue formation for the modified scion Ono graft, the bark graft, or the whip-and-tongue graft was significantly larger than the standard Ono graft or the splice graft. In a close examination of the cross sectional areas of the graft union formation through the microscope, the bark graft was superior, the standard Ono graft was inferior and rest of the grafting methods were intermediate.ing methods were intermediate.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.3
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• pp.171-175
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• 2000

The ultrastructures of germinal cells of male marsh clam, Corbicujar lena were studied. The mature sperm was primitive type, consisting of head, middle piece and tail. The mature sperm was whip-shaped and its head was divided into two parts; the acrosomal part shaped long hollow cone about $3{\mu}m$ in length and the sperm nuclear part shaped a long stick about $9\;{\mu}m$ in length. The posterior part of the sperm nuclear projected to centriole, The middle piece of the sperm-nuclear had four mitochondria and two centrioles. The sperm tail part had the 9+2 microtubular arrangement known as a typical pattern, During spermiogenesis, chromatin within sperm nuclear became fiberic materials by condensation.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.2
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• pp.238-246
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• 2008

This case study refers to turbine-generator with retrofitted turbine rotor. Vibration problem occurring after the retrofit was mainly due to high vibration from exciter side. However, repeated test run and operation during scheduled maintenance caused high vibration from generator bearing, and post-overhaul test run before turbine vibration correction caused oil whip on the bearing. This case study shows how to analyze vibration condition of high turbine generator vibration detected during the post-overhaul test run and vibration condition of offline and online data to reflect it on establishing maintenance schedule and overhaul correction procedure. Vibration data could be acquired during steady load operation or even with varying speed and load. Each data is important for machinery condition evaluation. This case study shows that the vibration data during extreme condition is the key factor in analysis, which helps to find the machinery problem.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.8B
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• pp.1021-1027
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• 2011

VHF is generally used for data or voice communications between ships and land stations. Although there exist many analytical and empirical channel models for radio waves on land, over-the-sea models are very limited to basic description. In this paper, a VHF channel is measured using vertical and/or horizontal whip antennas on shore and a moving ship for various ranges. The results show that the Doppler shift and changes in power for various ranges are observed. We can also find that the statistical analysis results in that the statistical parameters are rapidly changes, especially for V/H and H/V channels.

• Applied Microscopy
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• v.45 no.3
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• pp.144-149
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• 2015

Nothobranchius guentheri and Nothobranchius patrizii have special life cycle to sustain the dry season. So, we investigated the fertilized eggs morphology, and compared ultrastructures of surface structures and the cross section of fertilized egg envelopes using light and electron microscopes to determine whether these fertilized eggs and egg envelopes show the species specificity or have special structure to sustain the dry season. These fertilized eggs were spherical, yellowish, demersal and adhesive, and had a one-sided large oil droplet. The whip-like structures, adhesive filament were distributed throughout egg envelope in both species. But, that of N. guentheri was covered with fibrous structures, and that of N. patrizii was smooth. The egg envelope consisted of two distinct layers: an outer, electron-dense layer containing adhesive filaments and an inner layer of 16 to 17 horizontal electron-dense lamellae alternating with 15 to 16 interlamellae of lower electron density in both species. The external shapes of fertilized egg and section of fertilized egg envelope were same, but ultrastructure of adhesive filaments on the outer surface was concluded to show species specificity. Our data indicate that the ultrastructural differences of adhesive filament and outer surface of fertilized egg envelope show species specificity although these species belong to same genus.

• Journal of the Korean Society of Clothing and Textiles
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• v.46 no.1
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• pp.147-164
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• 2022

The aim of this study was to reproduce the ordinary attire of Yi Seung-hyu, a civil official and writer of the late Goryeo, which will be used to make a his portrait. The reproduced costume consists of a single-layered pyoui (表衣) and jungdan (中單), lined jeogori and baji, and geon (巾), created with reference to historical documents, materials, and portraits. The pyoui was made with samcheokbe, with an H-shaped neck-shoulder band, an oblique single collar, and rectangular gussets. Two skirts were attached on the inside at the back, similarly to dopo. The jungdan also has an oblique single collar, but has an I-shaped neck-shoulder band and triangular gussets. A flat felled seam stitch, whip stitch, and French seam stitch were used in the hemlines and seams of the pyoui and jungdan. The jeogori and baji were made with toju (土紬), and small ties were attached to stabilize them. The geon is a long, oblique hat, which has folded side lines, and was made with flexible black hangra and using a French seam stitch and backstitch. The results include the elements of "restoration, historical research, and portrait costume", and will be maintained as the cultural heritage of Samcheok City.

• Proceedings of the Korean Society of Computer Information Conference
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• 2023.01a
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• pp.315-316
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• 2023

본 논문에서는 딥러닝을 활용하여 KBO (Korea Baseball Organization)의 다음 시즌 플레이오프 진출 확률을 예측하는 Deep Neural Network (DNN) 시스템을 설계하고 구현하는 방법을 제안한다. 연구 방법으로 KBO 각 시즌별 데이터를 1999년도 데이터부터 수집하여 분석한 결과, 각 시즌 데이터 중 경기당 평균 득점, 타자 OPS, 투수 WHIP 등이 시즌 결과에 유의미한 영향을 끼치는 것을 확인하였다. 모델 설계는 linear, softmax 함수를 사용하는 것보다 relu, tanh, sigmoid 함수를 사용했을 때 더 높은 정확도를 얻을 수 있었다. 실제 2022 시즌 결과를 예측한 결과 88%의 정확도를 도출했다. 폭투의 수, 피홈런 등 가중치가 높은 변수의 값이 우수할 경우 시즌 결과가 좋게 나온다는 것이 증명되었다. 본 논문에서 설계한 이 시스템은 KBO 구단만이 아닌 모든 야구단에서 선수단을 구성하는데 활용 가능하다고 사료된다.

• Journal of Convergence for Information Technology
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• v.10 no.9
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• pp.237-243
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• 2020

This study examines the inequality of female golf leaders in recruitment and promotion and investigates alternatives to overcome them. It consisted of in-depth interviews and observations of the participants of this researcher by 9 female golf instructors who were employed in the driving range and had more than 10 years of teaching experience. Area analysis and classification analysis were used, and expert consultation, triangulation verification, and reconfirmation with participants were performed. The results first, Female golf leaders were unable to compete equally in the network of male golf leaders who advanced first. Second, female golf leaders were faithful to the role theory of women who have been educated in Confucian culture in Korean society. Third, to overcome the gender inequality reality, education was selected and self-esteem was raised through education. Fourth, fair opportunities should be given through job postings and job standardization. Lastly, it was confirmed that the proportion of athletes soon leads to the proportion of leaders, and that the number of leaders becomes a condition for equality.