• Transactions of the KSME C: Technology and Education
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• v.5 no.2
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• pp.115-126
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• 2017

This paper proposes an accelerated life evaluation of drive shaft for the power train parts of special purpose vehicle. It is necessary the real load data of usage level driving load condition for life evaluation of power train parts, but we can't get the load spectrum data for evaluation in many case of special purpose vehicle. So, in this paper, the road load spectrum data for evaluation is created by modeling and simulation based on vehicle data and special road condition. The inverse power model is used for accelerated life test. The equivalent torque of load spectrum is achieved using the Miner's Rule. This paper also proposes the calibrated acceleration life test method for drive shaft. The fatigue test is performed through three stress levels. The lifetime at normal stress level is predicted by extrapolation, and is verified through comparison of experimental results and load spectrum data.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.1
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• pp.1072-1076
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• 2005

Importance of XML as a target of Data Mining is growing because XML is used generally as a standard markup language for describing structured data. Especially researches have been done about extracting wanted informations by applying association rules to XML documents. But there are few development about solving the problems of method for efficiently obtaining informations from similar kinds of XML documents. To solve the problem this paper tries to suggest the method by which common XML structure is extracted form the same kinds of XML documents having a various XML schemas. The resulted schema structure is supposed to be important one as a preliminary job because it helps us to acquire the useful informations from various kinds of documents by unifying their structures.

• Journal of Advanced Navigation Technology
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• v.24 no.4
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• pp.305-313
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• 2020

Telemetry system is a system that transmits status information data acquired from the aircraft to the ground station. PCM encoder needs memory to store channel information in order to generate a frame format using the acquired data. Generally, telemetry systems in large aircraft require much larger memory for the increased acquisition channel information due to the increased sensors and subsystems. However, they have difficulty to store all channel information in limited memory. In this paper, we suggests and implements an advanced PCM encoder that can efficiently manage memory by minimizing duplicated channel information. This novel PCM encoder allocates duplicated channel information to memory only once. And, sub commutation channels having different information for each minor frame are allocated to the memory by multiples of sub commutation channels. Finally, the suggested PCM encoder was proved by simulation that composed channels of various measurement cycles.

• Journal of Plant Biotechnology
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• v.42 no.3
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• pp.265-270
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• 2015

The roots of Codonopsis lanceolata (Campanulaceae) contain several kinds of triterpenoid saponin with high medicinal values, which have been used in traditional medicines. This study investigates the impacts of methyl jasmonate (MeJA) - adding time on the saponin synthesis and the hairy root growth of C. lanceolata. A significant decrease in major saponin (lancemaside of three kinds) content of hairy roots was observed with MeJA treatments. Contents of lancemaside A, B and E decreased about 15% more than non-treated hairy roots. In contrast, minor saponin (foetidissimoside A and aster saponin Hb) accumulation was about 15% higher than the non-treated hairy roots. These results suggest that MeJA treatment could be used in the production of teriterpene saponins.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.114-119
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• 2004

Endbeam is an important structural member of freight bogie for the support of service loading. In general, more than 25 years' durability is necessary. However, endbeam occur fatigue fracture in dynamic stress concentration location because comparatively strength and stiffness are low. Therefore, structure analysis is performed to evaluate structural problem of endbeam and local strain range as durability analysis. The number of cycles is extracted concerning the bogie in operation by measurement dynamic stress time history on critical part which is crack initiation in actual fact. At this time rainflow cycle counting is used to consider change of stress for operating condition. Based on the fatigue life curves and the stress analysis, the fatigue life of the endbeam is predicted and compared with the experimentally determined fatigue life, resulting in a fairly good correlation.

• The Journal of the Korea Contents Association
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• v.14 no.9
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• pp.437-449
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• 2014

In order to suggest alternative directions for the regional development of Chungcheongbukdo through social network analysis (SNA) methods, this study highlights networking features of Chungcheongbukdo-based top 300 enterprises. In particular, it has paid attention to network relationships among participating enterprises and their basic structure, all of which play pivotal roles in provincial development. Major networking features among Chungcheongbukdo-based top 300 enterprises are dichotomized between structural and positional dimensions. Firstly, in terms of structural approach, this research confirms that both relational density indices and average connectivity levels among key enterprises have been extremely low. Therefore, the exchange networks seem relatively limited. That is, two enterprises could be interconnected after 1.1 stages in average, implying that the most popular types come from direct relationship among participating enterprises. In addition, this research finds that 7 major networks hinged upon 'distributed centralization types' present active information exchange, taking in charge of brokerage roles, all of which have contributed to broader network formation. Nonetheless, as the weight of minor network outweighs that of major network, more active supporting measures should be designed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.2
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• pp.167-173
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• 1981

Respiration of whole seeds and seed parts isolated from four soybean varieties Essex, Pickett, Wayne and Bonus as measured at $25^{\circ}C$ during germination. The average respiration rates of cotyledons were significantly higher than those of other parts. The values were 35.7, 28.0 and $23.9{\mu}hr^{-1}$ seed$^{-1}$ for cotyledons, embyros, and hila, respectively. Bonus showed a significantly lower respiration rate than the other varieties did. The interaction of variety x seed part was not significant source of variation for respiration. This suggests that seed part and variety independently contribute to soybean seed respiration during early imbibition. The effects of imbibition time and time x variety intereaction on whole seed respiration were significant, but the variety effect was not significant. The correlation coefficient between seed moisture content and respiration after 24 hours of imbibition was significant for Bonus, but not for the other varieties tested. This suggests that Bonus may require more water for respiration during imbibition than the other varieties. There as no significant correlation of whole seed respiration rate after 24 hours imbibition with seed weight or seedling length.

• The Journal of the Korea Contents Association
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• v.13 no.8
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• pp.386-395
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• 2013

This study examined social relation of cyber sports supporter's community and social capital as time passes. This study selected spectator sports supporters of cyber sports community based on number of number and history of cyber sports supporter. This community is a representative supporter's club of spectator sports. This study utilized 1,848 members accumulated during three month. To analyze data, Netminer 4.0 and social network analysis were used. The conclusion is following: First, social relation of cyber sports supporter's community showed up dynamic change. Second, social capital of cyber sports supporter's community shows Sports events and training schedules, player transfer, manager, record, game watching and TV watching, cheering, cheering uniform and tools, players, teams and clubs, game photos and video, etc. This is the poor-get-poorer and the rich-get-richer phenomenon.

• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.2
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• pp.1-9
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• 2005

An end beam is one of the most important structural members supporting uncovered freight under in-service loading. In general, it needs to endure over 25 years. However fatigue fracture has occurred at dynamic stress concentration location of the end beam because user's specifications demanded high speed and vehicle manufacturer made the uncovered freight car with comparatively low strength and stiffness. For durability analysis, finite element analysis is performed to evaluate the problem of uncovered freight structure and local strain. The uncovered freight car was operated on actual problematic railroad line to measure dynamic stress versus time history on the critical part from which a crack is initiated often. Rainflow cycle counting method was used to estimate fatigue damage at dangerous area under operating condition. Therefore, this study shows that analytical fatigue life at the end beam can be predicted on the basis of S-N curve and structure analysis and has a fairly good correlation with experimental fatigue life.

• Journal of the Korea Convergence Society
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• v.10 no.4
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• pp.229-236
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• 2019

The purpose of this paper is to analyze social phenomena and perceptions by collecting and analyzing data on public opinion, views and trends related to special case of military service in the sports community through Big KINDS operated by the Korea Press Promotion Foundation. To this end, the related keywords were derived and visualized by implementing a LDA(latent dirichlet allocation) technique to derive problems found in social phenomena based on big data analysis. The topics derived include "re-lighting special case on military service," " military service corruption controversy," "special case of military service for athletes," "alternative military service system for artists " and "parliamentary inspection of the administration" This could be used as a basic data for identifying accurate information on social controversies related to special case of military service in the sports community and drawing up practical measures that are considered in line with the principle of just and equal burden.