• Korean Journal of Soil Science and Fertilizer
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• v.48 no.2
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• pp.132-137
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• 2015

Effects of chitin and chitosan treatments on soil microorganisms and the mesofauna were investigated in a microcosm and a fumigated field experiment. Responses of microorganisms were determined using microbial phospholipid fatty acid (PLFA) analysis, whereas responses of the mesofauna were measured in terms of the abundances of nematodes and microarthropods. Soil nitrate concentration increased on the application of chitin. Overall, chitin promoted bacterial and fungal abundance, leading to an increase in abundance of free-living soil nematodes that feed on decomposers. The ratio of saturated to unsaturated fatty acids was highest in the chitin-treated soil. Chitosan had a minimal effect on the abundance of microorganisms; however, it reduced the abundance of collembolans in the microcosm experiment. These results indicate that the application of chitin has beneficial effects on the supply of nutrients and promotion of the abundance of soil organisms.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.22 no.3
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• pp.24-32
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• 2014

Due to the rapid growth of domestic and overseas airline markets, the demand for airline pilots has also been growing fast. Meeting such a market needs, central government, Ministry of Land and Transportation has set up civil airline pilot training center at Ulgin airport to train and provide the market with commercial airline pilots. Not only central government but universities in Korea also have tried to train pilots by operating flight training academies. Even though there are more than a dozen of flight training centers including colleges and private academies, there have been less efforts to measure and evaluate the effectiveness of the flight training school's curriculums compared to other scholar majors in a university. Therefore this paper tried to evaluate the educational effectiveness of the curriculums using the Kirk-Patrick measurement model, which has been regarded as one of the most popular and accurate measurement tool for an empirical research in social science. According to the empirical research, it was found out the inter-personal relationship between an instructor pilot and flight trainee was perceived as the most important factor to have an impact on learning abilities and student's behaviors.

• Korean Journal of Environmental Agriculture
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• v.24 no.3
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• pp.289-294
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• 2005

The toxic effects of 12 commercially available insecticides on the earthworm, Eisenia fetida (Savigny), were evaluated using artificial soil, surface sprayed soil, immersion, and contact filter tests. The risk to earthworm was assessed by the TER (toxic exposure ratio) value, which was calculated by the formula, TER=NOEC/PEC (predicted environmental concentration). TER was 3 for methomyl SL, 20 for carbaryl WP, 20 for phosphamidon SL, 30 for imidacloprid WP, and 60 for dichlorvos EC the in artificial soil test. At recommended, the earthworm mortality to methomyl SL reached 50% in the surface sprayed soil test, 72% in the immersion test, 30% in the contact filter paper test, whereas that to imidacloprid WP reached 56, 32, and 100 respectively. As a result of the four methods, methomyl SL and imidacloprid WP would be toxic insecticides to earthworm.

• Journal of Digital Contents Society
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• v.6 no.2
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• pp.131-135
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• 2005

Nowadays, the demand for the wireless technology has gradually increased to support the services of high speed wired internet and also the interest of a mobile terminal convergence has increased. In the next generation, the mobile terminal could merge with the celluar phone, wireless LAN, portable internet, digital multimedia brodcasting, mobile game and sensor(smart-tag and biometrics) through the unified single user interface. Moreover, the system is supported to multi-mode at difference networks, which have variable functions and high performance for available service. Inthis paper, we investigate the minimum requirements and the core technologies of the next generation mobile terminals.

• Journal of Digital Contents Society
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• v.5 no.4
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• pp.283-288
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• 2004

This paper presents research in intelligent massenger technique for Cyber University to support accessing university database. Proposed techniques enables better communication between students and professons by using intelligent messenger. Intranet based massenger support simple message transfer and multimedia chatting service within homogeneous network or members in same group. Using niversity database it provide personalize information for each different user demand needs and through managing technique user could effectively organize members of group. To embody intelligent massenger, JMF(Java Media Frame Work), RMI(Remote Method Invocation), XML techniques were proposed and in result constructing effective community.

• Journal of Digital Contents Society
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• v.7 no.3
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• pp.211-217
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• 2006

The digital contents industry has now become the most important industry in the 21st century. Among the various digital contents industries, the animation industry has emerged as a higher value-added culture contents business with a strong possibility of growth from the field of image and character to the copyright area. Yet, the overall market structure has not been consolidated except for a few successful projects because of the sharp decline in domestic animation and the upward trend in global animation business. Due to reduced investment in producing TV animations, OSMU is an essential alternative for the animation industry. In this research, we aim to analyze the development of the domestic animation industries by studying the actual condition of OSMU for broadcasting contents.

• Journal of Digital Contents Society
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• v.8 no.1
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• pp.9-15
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• 2007

Smoothing is a transmission plan where variable rate video data is converted to a constant bit rate stream. Among them are CBA, MCBA, MVBA, e-PCRTT and others. e-PCRTT algorithm, which was improved from PCRTT, restricts the number of rate changes with fixed-size run. This causes unnecessary rate changes when run size is small and buffer size is large. In this paper, to overcome a shortcoming of e-PCRTT algorithm, a smoothing algorithm is proposed, which is improved from e-PCRTT, where a transmission rate transmits more intervalsl as possible. Experiments demonstrated that the proposed algorithm outperformed e-PCRTT algorithm. In order to show the performance, various evaluation factors were used such as the number of transmission rate changes, peak rate, transmission rate variability and so on.

• Journal of Digital Contents Society
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• v.5 no.3
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• pp.205-212
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• 2004

This paper presents a design and implementation example of intelligent society member management system that is constructed to induce various research activity. Based on members data and society activity record, the system executed data mining. In the process of data mining useful society activity rules was produced and in result members could effectively interact with the system. Decision Tree Algorithm was used in the process, which is one of the methods of data mining. We presemts a plan for personalization website to provide user oriented administration policy and dynamic interface by using analyzed information of society activity rules produced.

• Convergence Security Journal
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• v.13 no.1
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• pp.51-57
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• 2013

RSA is the most widely used public key algorithms. Payment via the SSL communications, and user authentication using RSA secure shopping mall that can protect the user's valuable information in the process of building. SSL-based electronic signature technology and encryption protocols for this technology are electronic documents are delivered to the other party through a separate encryption process, the information sender to enter information on a web browser (user) and the recipient (the Web server of the site Manager), except you will not be able to decrypt the contents. Therefore, the information is encrypted during the transfer of electronic documents even if hackers trying to Sniffing because its contents can never understand. Of internet shopping mall in the user authentication 'and' Communications' SSL secure shopping mall built with the goal of the methodology are presented.

• Journal of Digital Contents Society
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• v.6 no.4
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• pp.267-272
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• 2005

The ubiquitous computing environment is a new paradigm that represents the future life and is expected to bring about great changes in IT and in the lives of individuals. However, since a good deal of information can be easily obtained and shared in the ubiquitous computing environment, problems such as a security threat and infringement of privacy are getting serious. The present study is intended to explore some ways to minimize such problems by introducing RFID technology in the ubiquitous computing environment. This study also examines the causes of violation of security and privacy that might occur in the RFID system and requirement for security. In addition it seeks possible technical solutions to those causes.