• Proceedings of the KWS Conference
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• 2003.05a
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• pp.117-119
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• 2003

Power plant efficiency and availability depend greatly on condenser performance. However, during commissioning of Yeonggwang #1/2 steam condenser sodium leakage occurred, because of tube to tubesheet only roll expanding. Therefore this report is explaining that pre-test for the shake of improvement reliable repair processes & selected sampling tube re-expansion in-situ applications.

• Journal of the Society of Naval Architects of Korea
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• v.61 no.5
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• pp.297-311
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• 2024

In this study, a combined seakeeping performance evaluation method has been developed for the design purpose of the light aircraft carrier CVX of Korean Navy. A frequency domain analysis method was developed for evaluation of safe operating envelope up to sea state 6, while a time domain analysis method was developed for survival condition of sea state 7 and higher. The frequency-domain solver AdFLOW-Navy was developed by adding empirical formula of roll damping and fin-stabilizer to the existing AdFLOW by KRISO, which was based on the three-dimensional higher order boundary element method (HOBEM). For the estimation of the roll damping coefficient, a two-dimensional cross-section was automatically extracted from the three-dimensional panel, and the roll damping coefficient was analyzed for the two-dimensional cross-section. As for the time domain analysis method, KIMAPS-Navy was developed by improving and expanding the KIMAPS series developed by KRISO which is based on the impulse response function by utilizing the hydrodynamic coefficients obtained from the AdFLOW-Navy. In addition, a weakly nonlinear analysis approach was applied to analyze highly nonlinear motion under heavy sea states. Finally numeraical analysis results were compared with model tests, which showed practical usefulness of the present combined seakeeping analysis approach.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.6_2
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• pp.1029-1036
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• 2022

The traditional outdoor advertising market has been stagnant recently, but the digital advertising market has been steadily increasing, and the digital signage market has been expanding despite the recent corona pandemic. However, in terms of hardware, new displays are required due to excessive power consumption, lack of visibility in sunlight, and continuous operating expenses. Since the e-paper display does not require a light emitting device therein, it is advantageous to solve above problems. In addition, it has the advantage of consuming power only when converting an image due to bistability, so it is suitable as hardware that implements images rather than moving pictures. Currently, one of the most successful examples of commercializing e-paper displays is ESL devices. According to a recent market study, the market for large-sized panels larger than 10 inches has grown at an annual rate of 21.6%, and the market is expected to exceed 30% by 2026. It is judged that it will be relatively easy to apply the roll-to-roll technology, which is currently developing the technology applied to OLED, to the e-paper display. Therefore, mass production technology and market expansion for ESL panel enlargement are expected, and a new market is also expected to be formed at the same time. New markets will be traffic signs, public displays, billboards, façades, kiosks, digital signage, and so on.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.6
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• pp.98-104
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• 1999

As the accuracy of manufactured goods needed high accuracy processing has made the efficiency of NC and measurement technology development, the innovation of machine tools has influence the development of the semi-conductor and optical technology. The movement errors can be expressed in terms of yaw, roll an pitch etc. In the case of expanding the error range, static, dynamic and servo gain errors can be included. Machining center might have twenty-one movement errs including three types of joint errors. Those errors have been measured on the condition of just loading of standard table. Regarding these measuring methods, the mechanical compliance of the structure has not been considered. In this paper, therefor, the influences of the additional load on the positioning accuracy are investigated. The results and the techniques proposed in this study can be considered very effective and useful to compensate more correctly the positioning motion.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.219-222
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• 2007

Today, use of high resolution satellite image with at least 1m resolution is expanding into many more areas including forest, river way, city, seashore and so forth for disaster prevention. Interest in this medium is increasing among the general public due to the roll-out to the private sector as Google earth, Virtual Earth and so forth. However, pre-processing process that revises the geometrical distortion that result at the time of photographing is required in order to use high resolution satellite image. The purpose of this research is to search the most accurate GCP(Ground Control Point) information acquisition method that is used for the revision of high resolution satellite image's geometrical distortion through automated processing. Through this, it is possible to contribute to increasing the level of accuracy at the time of high resolution satellite image revision and to secure promptness.

• Journal of the Korean GEO-environmental Society
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• v.23 no.1
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• pp.31-37
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• 2022

This study is focused on developing a technology to prevent high-strength wire net from expanding damage due to insufficient performance of the existing PVC coating net. For the test method, reference was made to ISO 17746, an international standard. In addition, as a result of referring to the test criteria, a wire net was fabricated with a width of 1,000 mm or more a size of 1 m² sample. load-displacement curve of the test results was compared to analyze how much performance was improved compared to the existing PVC coating net.

• KSCI Review
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• v.11 no.1
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• pp.9-17
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• 2003

Along with trends of other countries, the Ministry of Information and Communication in Korea decided to operate an Information System Audit Institution for raising qualify of computer network facilitated in state organ and public institution, and to construct effective construction of information system. The aim of the audit institution is applying it to public information business, establishing an information system audit qualification system, and upbringing Private audit organs. The Ministry of Information and Communication realized that although the demand of information system area audit is explosively expanding, the National Computerization Agency cannot satisfies the demand and realize to have audit control for the information of national business as well. The Ministry of Information and Communication plan to enforce the audit on public information business by correlate with information business. The ministry enforce that the supervisory company has major roll to audit and national import business decided by the Information Promotion Committee is subject to have audit control. Therefore, in this paper, the contents of internal audit among internal/external audit will be presented.

• Korean journal of applied entomology
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• v.16 no.3 s.32
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• pp.163-170
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• 1977

Potato diseases, especially mosaics and leaf roll, appear to reduce potato yield in Korea more than any other factor. A seed potato certification program was established at the Alpine Experiment Station (AES) in 1961 to produce high quality seed potatoes for distribution to Korean farmers. The present program for production of certified seed of Namjak (Irish Cobbler), the only variety recommended for spring plantings, is outlined. In 1976, approximately 10,000 MT of certified grade Namjak seed was produced by members of two Seed Producers Cooperatives in the Daekwanryeong area for distribution by the Office of Seed Production and Distribution (OSPD). The seed was inspected and certified by officers of the National Agricultural Products Inspection Office (NAPIO). Although the quality of the certified seed is far superior to that used by many farmers, the supply planted less than 1/5 of the 1977 potato crop. Certified seed of Shimabara, the variety recommended for autumn plantings, is not produced in Korea. The yield response of virus infected seed to improved cultural practices is poor. Therefore, an increase in potato acreage and yields appears to be possible only if more good quality seed is used by Korean farmers. A two or three fold increase in seed supply would be desirable. The volume of seed could be increased by expanding the production area and by improving yield in seed fields. More land is available in the alpine area and good seed potatoes could be grown in other parts of Korea. Planting better quality seeds and using better cultural pracitces would improve seed yields. Several techniques could be used to improve the quality of elite seed produced at AES. Changes in seed potato certification program should be made so that healthy seed stocks of new varieties can be released rapidly.