• The Journal of Korean Society for Radiation Therapy
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• v.32
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• pp.73-83
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• 2020

Purpose: The purpose of this study is to confirm the matching of the electron density between tissue and gas due to variation of abdominal gas volume in MRgART (Magnetic Resonance-guided Adaptive Radiation Therapy) for pancreatic cancer patients, and to confirm the effect on the dose change and treatment time. Materials and Methods: We compared the PTV and OAR doses of the initial plan and the AGC(Abdominal gas correction) plans to one pancreatic cancer patient who treated with MRgART using the ViewRay MRIdian System (Viewray, USA) at this clinic. In the 4fx AGC plans, Beam ON(%) according to the patient's motion error was checked to confirm the effect of abdominal gas volume on treatment time. Results: Comparing the Initial plan with the average value of AGC plan, the dose difference was -7 to 0.1% in OAR and decreased by 0.16% on average, and in PTV, the dose decreased by 4.5% to 5.5% and decreased by 5.1% on average. In Adaptive treatment, as the abdominal gas volume increased, the Beam ON(%) decreased. Conclusion: Abdominal gas volume variation causes dose change due to inaccurate electron density matching between tissue and gas. In addition, if the abdominal gas volume increases, the Beam ON(%) decreases, and the treatment time may increase due to the motion error of the patient. Therefore, in MRgART, it is necessary to check the electron density matching and minimize the variability of the abdominal gas.

• Journal of Fisheries and Marine Sciences Education
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• v.23 no.2
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• pp.302-318
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• 2011

The object of this study is to provide easily-understandable mathematics class to highschool students, who usually take no interest in mathematics, by apply teaching strategy based on storytelling to real lessons. The approaching methods for the mathematics education are emphasizing the mathematical education during making storytelling-studying plans, inducing the interest of the students by applying the mathematical situations in the story. The effects of the storytelling such as induction of the interest, persistency, perception of the practicality, smooth communication between teachers and students coincides with the way national mathematical education orients. This study contains the definition of the storytelling based on education, and applicability to the students, and application to the real lessons, and verification of the effects by focus-group interview with the students and observing teachers. I made the lesson plan based on storytelling for achievements to the object of the highschool mathematical study, and searched the best way to apply the lesson plan to the real lessons. I studied designing lesson strategy based on dissertations and books and reports directly related this study, and did focus-group interview to find advantages and disadvantages of the strategy. And finally I could make the well-applicable lesson plan.

• Journal of the Korean Society for Railway
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• v.9 no.3 s.34
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• pp.319-324
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• 2006

Studied was a strategy of technology development for railway system in terms of railway network. First, The successful launch of the Korean HST system has not only decreased logistics burden but also significantly transformed the Korean trunk-line railway network, revolutionizing the logistics and technology sectors and reinvigorating the Korean railway industry in one century. Korean railway industry sector is now investing to develop many different types of railway system(G7, Post G7, tilting train...) so that these kinds of various railway system development should be integrated with the National Inter-modal Transportation Network Plan. To secure sufficient capacity that is required by the National Railroad Plan, the railway industry needs to establish mid- and long-term train purchase and operation strategies in compliance with railway construction and operation policies. During a railway construction planning, train operators, based on their train operation strategies, should come up with measures to closely cooperate with project operators from the planning stage through to the opening of a railway system. To be more precise, train operators should establish long-term train procurement plans reflecting both long-term national railroad network plans and plans for each railway line in order to suggest appropriate roles and schedules for each line. Also, based on the long-term railway plan, directions should be decided concerning the research and development of trains in advance.

• Hwankyungkyoyuk
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• v.17 no.2
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• pp.10-25
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• 2004

This study aims to standardize and analyze the environmental teacher recruitment examination for secondary school. To achieve the purpose, the environmental teacher recruitment examinations, which were carried out for five times through the school year 2000 to 2004, were compared and analyzed. And then, based on the above analyses, we presented ‘the plan of standardization for the environmental teacher recruitment examination in secondary school.’ In addition, the propriety, reliance, and realistic suitability of the plan were confirmed by professors of environmental education department in universities, environmental education professionals, and environmental teachers in secondary school. By presenting ‘the plan of standardization for the environmental teacher recruitment examination in secondary school’ in this study, we expect that the curriculum design and management of environmental education teacher training universities can be standardized and improved, and that the teacher who have expert qualities in environment education is reasonably selected by the environmental teacher recruitment examination.

• International conference on construction engineering and project management
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• 2005.10a
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• pp.786-790
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• 2005

As the scale of building construction is larger and more complex and the adaptation of new technology is increasing, the tendency of the risk serious accident cases is increasing now. Especially, the accident rate is below 10% at the building construction workers in Korea but among the total industrial accidents it exceeded by 35%. To prevent a construction accident, it is essential that not only to have a through grasp of the characteristic of safety problem but also to establish of efficient safety counter plan are required. According to the type and situation of building construction, the acquirement of necessary information is useful to prevent the hazard of work and establish the counter plan. Among the safety information it is a thing of especial importance that to estimate the hazard of work types for building construction to prepare the counter plan of safety. This study will analyze all of the1600 accidents of the building construction works from the data of KOSHA(Korea Occupational Safety &Health Agency) which were collected during 11 years(1992~2002) data relating to serious accidents of the building construction works, and suggest the counter plan according to the each work type in building construction works.

• Communications for Statistical Applications and Methods
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• v.8 no.2
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• pp.383-394
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• 2001

This paper is a generalization of single and two-level skip-lot sampling plans to n-level. On every skipping inspection of the n-level skip-lot sampling plan, not only the number of consecutive lots to be accepted but also the fraction of lots to be inspected can be freely choosed. The general formulas of the operating characteristic function, average fraction inspected, average sample number and average outgoing quality in n-level skip-lot sampling plan are derived. The operating characteristic curves, average sample number and average outgoing quality of a reference plan, two-level and five-level skip-lot sampling plans are compared.

• Ocean Systems Engineering
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• v.2 no.1
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• pp.69-81
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• 2012

Presented herein is a study on reducing the hydroelastic response of very large floating structures (VLFS) by altering their plan shapes. Two different categories of VLFS geometries are considered. The first category comprises longish VLFSs with different fore/aft end shapes but keeping their aspect ratios constant. The second category comprises various polygonal VLFS plan shapes that are confined within a square boundary or a circle. For the hydroelastic analysis, the water is modeled as an ideal fluid and its motion is assumed to be irrotational so that a velocity potential exists. The VLFS is modeled as a plate by adopting the Mindlin plate theory. The VLFS is assumed to be placed in a channel or river so that only the head sea condition is considered. The results show that the hydroleastic response of the VLFS could be significantly reduced by altering its plan shape.

• Journal of Korean Society for Quality Management
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• v.50 no.4
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• pp.635-646
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• 2022

Purpose: In this study, the detailed implementation plan for product safety evaluation and management suggested by KS A ISO 10377 to reduce the risk of harm to consumers and users is presented so that companies can strategically implement it. Methods: In order to achieve the purpose of this study, the upper elements and detailed execution plans shown in KS A 10377 are classified into hierarchies and set as a decision hierarchy. A pairwise comparison is performed to derive it. Results: Among the top factors, 'design safety (D)' was the most important factor, with 0.314. Therefore, ensuring safety in the design stage that can prevent defects in advance is the most important action plan for companies to supply safe products. Conclusion: The results of this study, it is intended to help companies and related organizations more easily understand and continuously apply KS A ISO 10377.

• Korean Journal of Agricultural Science
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• v.37 no.1
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• pp.105-112
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• 2010

The objective of this study is to develop a standardized model for analyzing water balances in large scaled water basin by considering agricultural water districts, and to evaluate the hydrological feasibility of applying this model to several water districts such as Nonbul, Geumbok, Daejeon 1, Daejeon 2, and Cheonggang in Geum river basin. Ten types of stream network were considered in developed model. Using this model, streamflows were simulated by major stations and water balances were analyzed by water districts. Simulated streamflows and measured streamflows were compared at check stations such as Gapcheon and Bugang stations in which Nash and Schcliffe's model efficiencies were 0.633, 0.902, respectively. This results showed its applicabilities to national water resources plan, rural water development plan, and total maximum daily load plan in Korea.

• International Journal of Computer Science & Network Security
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• v.21 no.2
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• pp.88-92
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• 2021

A method and a mathematical algorithm for finding a quasi-optimal assignment plan with rectangular efficiency matrices are proposed. The developed algorithm can significantly reduce the time and computer memory consumption for its implementation in comparison with optimal methods.