• Journal of the Korean Society for Precision Engineering
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• v.16 no.12
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• pp.204-213
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• 1999

This paper suggests a numerical method of finding optimal geometric path and minimum-time motion for a manipulator arm. To find the minimum-time motion, the optimal geometric path is searched first, and the minimum-time motion is searched on this optimal path. In the algorithm finding optimal geometric path, the objective function is minimizing the combination of joint velocities, joint-jerks, and actuator forces as well as avoiding several static obstacles, where global search is performed by adjusting the seed points of the obstacle models. In the minimum-time algorithm, the traveling time is expressed by the linear combinations of finite-term quintic B-splines and the coefficients of the splines are obtained by nonlinear programming to minimize the total traveling time subject to the constraints of the velocity-dependent actuator forces. These two search algorithms are basically similar and their convergences are quite stable.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.5
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• pp.317-321
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• 2014

Hydrothermal synthesis technique could be carried out for growth of ZnO nanowires at relatively low process temperature, and it could be freely utilized with various substrates for fabrication process of functional electronic devices. However, it has also a demerit of relatively slow growth characteristics of the resulting ZnO nanowires. In this paper, an external DC bias of positive and negative 0.5 [V] was applied in the hydrothermal synthesis process for 2~8 [h] to prepare ZnO nanowires on a seed layer of AZO with high electrical conductivity. Growth characteristics of the synthesized ZnO nanowires were analyzed by FE-SEM. Material property of the grown ZnO nanowires was examined by PL analysis. The ZnO nanowires grown with positive bias revealed distinctively enhanced growth characteristics, and they showed a typical material property of ZnO.

• Proceedings of the Korean Society of Crop Science Conference
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• 1998.09a
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• pp.22-34
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• 1998

Coarse grain crops including maize, sorghum, buckwheat, fox-tail millet, pearl millet, proso millet and barnyard millet have been used as health food, feed and industrial materials in Korea for a long time. Korean ancestors thought and treated them as the very important good crops for human health and the crops have served as a dish made with all the grains, particularly in January 15 of the lunar month in korea because the grains make the five viscera of heart, liver, spleen, lungs and kidneys and the six entrails of gall bladder, stomach, small and large intestines, the paunch, the bladder, and the bowels strong and build healthy body. Thus, the objectives of the paper were to review and summarize the results obtained from the quality breeding and functional researches worldwide on nutrition, utilization and medical action of the coarse grain crops. Maize grain, fresh ear and green fodder yields have increased since 1960s in Korea. Agronomic traits improvements also occurred for cold tolerance, disease and insect resistance, resistance to barrenness, resistance to loding, pollen production, grain and seed yields, and eating quality. For buckwheat, improved summer buckwheat varieties produced more rutin for vegetable and grain than autumn varieties in Korea

• Journal of Applied Biological Chemistry
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• v.56 no.3
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• pp.187-189
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• 2013

The antimicrobial activities of emodin and its derivatives (anthraquinone, alizarin, and alizarin-3-methyliminodiacetic acid) were evaluated using a paper disc diffusion method against foodborne bacteria (Bacillus cereus, Listeria monocytogenes, Staphylococcus intermedius, Salmonella typhimurium and Shigella sonnei). Emodin isolated from C. tora seeds has an antimicrobial activity against Bacillus cereus, followed by alizarin-3-methyliminodiacetic acid ($13.0{\pm}2.5mm$) and alizarin ($11.5{\pm}1.2mm$). Furthermore, emodin showed the antimicrobial activity against S. sonnei and S. typhimurium. In conclusion, C. tora seed and its active component derivatives are useful for the development of natural products on food supplemental agents and pharmaceuticals.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.11
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• pp.5731-5754
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• 2019

In this paper, we redesign, implement, and evaluate ShareSafe (Based on SecGraph), an open-source secure graph data sharing/publishing platform. Within ShareSafe, we propose De-anonymization Quantification Module and Recommendation Module. Besides, we model the attackers' background knowledge and evaluate the relation between graph data privacy and the structure of the graph. To the best of our knowledge, ShareSafe is the first platform that enables users to perform data perturbation, utility evaluation, De-A evaluation, and Privacy Quantification. Leveraging ShareSafe, we conduct a more comprehensive and advanced utility and privacy evaluation. The results demonstrate that (1) The risk of privacy leakage of anonymized graph increases with the attackers' background knowledge. (2) For a successful de-anonymization attack, the seed mapping, even relatively small, plays a much more important role than the auxiliary graph. (3) The structure of graph has a fundamental and significant effect on the utility and privacy of the graph. (4) There is no optimal anonymization/de-anonymization algorithm. For different environment, the performance of each algorithm varies from each other.

• Bulletin of the Korean Space Science Society
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• 2003.10a
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• pp.36-36
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• 2003

While it is presumed that substorm injection electrons of a few hundred keV are the seeds for relativistic electrons frequently observed during the recovery phase of storms, correlation between the two events has not been well explored with the observed satellite data. We would like to address this problem in the present paper using the data from the geosynchronous GOES and LANL satellites as well as from the polar orbiting NOAA satellites. Our statistical study shows the two channels of LANL SOPA instrument, 105 150 keV and 150 225 keV, best correlates with the increase of the flux levels of GOES relativistic electrons. Especially, the relativistic electron events are not observed when the flux levels of these two channels are maintained low in the substorm injections, regardless of the level of the ULF activities. The conclusion does not change whether the substorm injections occur . during the storm recovery phase or during the non-storm time. As the ULF waves are observed quite frequently over the entire range of L=4 to L=7, the reason why REEs are seen mostly during the storm time seems to be related to the fact that storm-time substorms produce more seed electrons than the substorms that occur during the non-storm time.

• The Journal of Society for e-Business Studies
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• v.10 no.2
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• pp.89-108
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• 2005

The SOAP specifications are not provided a functions of information security, especially authentication function. In case of user authentication, delivery of the username and password elements can be exposed to sniffing/replay attack by malicious attacker. In this paper, we propose a new mechanism to protect authentication attacks for the SOAP messages. The proposed mechanism is compensated for weakness of S/KEY system. Our mechanism has no limitation for time and overhead and also provide a more effective and secure delivery.

• International Commerce and Information Review
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• v.12 no.3
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• pp.267-288
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• 2010

The collapse of housing market bubble in United States had a considerable impact on the world economy. The collapse of housing market bubble in United States generates the global financial crisis at the worldwide level. The housing market bubble question the efficacy of fundamental proposition of orthodox economics based on the rationality of human choice. According to neuroeconomics and neuroscience, emotion and affect play the important role in purchasing the commodity in retails market. On the basis of the neuroeconomics, this study focuses on the role of affect and emotion in the purchase of subprime loan in United States. Robert Schiller suggests that one of the causes of housing market bubble is the contagion effect of human belief in the society. The structure of this paper is as follows. First, this study investigates the mechanism of human brain and role of various neurons to influence the human behavior in the purchase of house in United States, such as Dophamine neuron and mirroring neuron. Second, this study shows the possibility that the mirror neuron might explain the contagion of human belief in housing transaction market. It can be a seed of housing market bubble. Furthermore, this study show the implications of neuroeconomics is suggestive to the negotiation process in commercial policy in United States.

• Current Industrial and Technological Trends in Aerospace
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• v.6 no.2
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• pp.60-68
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• 2008

The characteristic and properties of materials are rapidly degraded when subjected to the synergistic effects of the space environment such as atomic oxygen, radiation, vacuum and thermal cycling. In order to understand the mechanism of material property variation in space environment and to develop new space materials applicable to the future space program, advanced space organizations such as NASA, ESA and JAXA have been continuing many researches on material test specimens used on ISSE(International Space Station Experiment) or LDEF(Long Duration Exposure Facility). In this paper, the selection requirements and verification trend of materials in space applications

• Journal of information and communication convergence engineering
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• v.7 no.4
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• pp.419-430
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• 2009

Reading comprehension (RC) systems are to understand a given text and return answers in response to questions about the text. Many previous studies extract sentences that are the most similar to questions as answers. However, texts for RC tests are generally short and facts about an event or entity are often expressed in multiple sentences. The answers for some questions might be indirectly presented in the sentences having few overlapping words with the questions. This paper proposes a conceptual graph matching method towards RC tests to extract answer strings. The method first represents the text and questions as conceptual graphs, and then extracts subgraphs for every candidate answer concept from the text graph. All candidate answer concepts will be scored and ranked according to the matching similarity between their sub-graphs and question graph. The top one will be returned as answer seed to form a concise answer string. Since the sub-graphs for candidate answer concepts are not restricted to only covering a single sentence, our approach improved the performance of answer extraction on the Remedia test data.