• Progress in Medical Physics
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• v.13 no.1
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• pp.32-36
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• 2002

For Intensity Modulated Radiation Therapy(IMRT), the spatial resolution of intensity map(IM) is limited by the width of multi-leaf collimator, which would make an effect on the conformity of the target, as well as organs at risk. Several Methods are suggested to increase the spatial resolution, which can be categorized by the hardware-dependent technique and the software-based technique. However the best solution might be to make the width of MLC finer. it has several obstacles in the respects of technical difficulty and cost. This preliminary study is designed to investigate the clinical effectiveness of the virtual-micro IMRT(VMIMRT) technique, one of the software-based technique. A particular intensity map was created, which has 42$\times$54 pixel dimension ,0.5cm pixel size and 15 intensity levels. Using this intensity map, segment fields of IMRT were generated with 1$\times$lcm, 0.5$\times$1cm, 0.5$\times$0.5cm(VMIM) beamlet size, respectively As results, we found that there was no evidence of improvement for VMIMRT, compared with the 0.5$\times$lcm beamlet size which can be delivered by 1cm width MLC. The reason seems to be due to the constraint of VMIMRT. Further study is required to prove the benefit of the VIMRT in clinical case like head and neck cancer, where is expected that higher resolution than 1cm is necessary.

• Journal of Food Hygiene and Safety
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• v.34 no.5
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• pp.489-494
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• 2019

The appropriateness of introducing blockchain technology into food safety management systems was evaluated by conducting a survey of experts on the effectiveness and constraint evaluation indicators, and a portfolio analysis was conducted to set the priorities of blockchain application. The food safety management activities considered in this study were issuing documents on food import/export, food hygiene rating scheme, civil complaint management in the food sector, food- related certification, risk information management, and food traceability systems. The sectors that can be expected to be effective in the introduction of blockchain technology were food- related certification, food hygiene rating scheme, risk information management, and issuing documents on food import/export. In the case of food traceability systems and civil complaint management, the introduction of blockchain technology was not recommended due to ineffectiveness. From the evaluation of the constraints (e.g., technical limits, cost, legal amendment, personal information disclosure, timeliness, and ease of connection) to be overcome when introducing blockchain into food safety management, it was found that there are more than average constraints in all six areas. In particular, the food traceability system was evaluated to have the most constraints. Issuing documents on food import/export is very effective with the introduction of blockchain technology, but due to high cost and legal restrictions, it is necessary to improve the institutional system in order to introduce blockchain. Among the evaluation sectors, food- related certification, food hygiene rating scheme, and risk information management on foods were suitable for preferentially adopting blockchain technology since these areas might experience greatly improved reliability and transparency through the introduction of blockchain, with relatively low constraints.

• Journal of International Area Studies (JIAS)
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• v.22 no.2
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• pp.81-110
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• 2018

In this paper, we examined the regional economic integration, the trade negotiation strategy and bargaining power of the European Union through the logical structure of the three - dimensional game theory. In the three - dimensional game theory, the negotiator emphasized that the negotiation strategy of the triple side existed while simultaneously operating the game standing on the boundary of each side game, constrained from each direction or occasionally using the constraint as an opportunity. The study of three-dimensional game theory is aimed at organizing the process of coordinating opinions and meditating interests at the international level, regional level and member level by the regional union as a subject of negotiation. This study would compare and analyze the recently concluded EU-Japan EPA (Economic Partnership Agreement) negotiation process with the case of the EU FTA, and summarize the logic of the three-dimensional game theory applicable to the FTA of the regional economic partnership. Furthermore, the study would illustrate the strategies of the regional economic cooperatives to respond to negotiations. The area of trade policy at the EU level has already been completed by the exclusive power of the Union on areas where it is difficult to politicize with technical features. Moreover, the fact that the policy process at the Union level has not been revealed as a political issue, and that the public opinion process is a double-step approach. In conclusion, the EU's trade policy process constitutes a complicated and sophisticated process with the allocation of authority by various central organizations. The mechanism of negotiation is paradoxically simplified because of the common policy decision process and the structural characteristics of the trade zone, and the bargaining power at the community level is enhanced. As a result, the European Commission would function as a very strong negotiator in bilateral trade negotiations at the international level.