• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.364-367
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• 2017

The basic design concept of the DACS(Divert and Attitude Control System) propellant is presented and the geometry optimization of the DACS propellant with limited outer diameter and maximum burning rate of the propellant is performed. Two-side burning surface conditions burned at the core and the one side of the propellant are applied to the propellant. And the optimized values for the radius of core, length of propellant, angle of end-side surface are obtained by the PSO algorithm. The direction for DACS propellant design is suggested by analyzing optimized design points for various burning rate.

• Hwankyungkyoyuk
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• v.8 no.1
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• pp.151-165
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• 1995

1. This paper suggests one educational model of National Parks. The model includes main themes such as (1) concepts, (2) waste types, and (3) conservation policies of National Parks for the application at the school environmental education classes. 2. The study describes the origin of the national park system and concepts or policies for the conservation of the parks with cases of Japan, Taiwan, Canada, Australia, Swiss, Russia, and International Union for the Conservation of Nature and Natural Resources(IUCN). The main focuses of their concepts or policies are on the (1) public land, (2) conserved, (3) legally protected land, and (4) land for the education of the loving their country. 3. This research classifies wastes of parks as point, linear, areal, and cubic types, and explains wasting actions on each types, focused mainly on the mountainous national parks. 4. The suggested policies for the conserving national parks, in this paper, are (1) core-zoning policy, and (2) management policy within the core zone. 5. Some principles are suggested for the more effective realization of the policies: (1) enforcement, (2) abandonment,(3) restoration, (4) enlargement, (5) limitation, (6) incorporation, (7) monitoring, and (8) education. 6. Finally, the educational values of this model may be derived from concepts of (1) loving national land, (2) conservation of nature, (3) public responsibility for protection, and (4) education materials. Those concepts form the foundation of models for (1) civic education, (2) education of country, and (3) inquiry training.

• Nuclear Engineering and Technology
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• v.40 no.2
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• pp.127-132
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• 2008

An experimental loop operating with water at supercritical conditions(25MPa, $600^{\circ}C$ in the test section) is designed for operation in the research reactor LVR-15 in UJV Rez, Czech Republic. The loop should serve as an experimental facility for corrosion tests of materials for in-core as well as out-of-core structures, for testing and optimization of suitable water chemistry for a future HPLWR and for studies of radiolysis of water at supercritical conditions, which remains the domain where very few experimental data are available. At present, final necessary calculations(thermalhydraulic, neutronic, strength) are being performed on the irradiation channel, which is the most challenging part of the loop. The concept of the primary and auxiliary circuits has been completed. The design of the loop shall be finished in the course of the year 2007 to start the construction, out-of-pile testing to verify proper functioning of all systems and as such to be ready for in-pile tests by the end of the HPLWR Phase 2 European project by the end of 2009.

• Perspectives in Nursing Science
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• v.17 no.1
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• pp.28-39
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• 2020

Purpose: To understand the core elements and the effects of interventions on the improvement of parenting capabilities of unmarried mothers living in residential facilities, this study reviewed the literatures related to this concept. Methods: Five electronic databases (KISS, KMbase, KoreaMed, NDSL, and RISS) were searched, and eight studies were ultimately selected for the integrative review. Results: The interventions were categorized into two types: psychological intervention and sociocultural intervention. The core elements of the psychological interventions included cognitive, emotional, behavioral, and relational contents. Sociocultural aspects included raising personal skills for finding social support resources. Various studies showed the effects of intervention on efficacy, attachment, or parenting behavior. Conclusion: Based on the results of this study, health promotion programs to improve maternal parenting competency for unmarried mothers living in residential facilities need to be developed and applied.

• Journal of Science and Technology Studies
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• v.3 no.2 s.6
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• pp.61-82
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• 2003

In a new paradigm of competition, firms face a multiple industry in a generation and compete with existing capabilities and resources in a new industry. Firms need to increase dynamic capabilities to adjust to a radical change in terms of technologies for survival and sustainable growth in a new industry. But we lack a clear conceptual model explaining evolutionary process of firms facing a emerging industry with different experiences in a prior industry and where heterogeneity in firms' technological portfolios come from. How we explaining firms' heterogeneity arising in a new industiy? In this article, I suggest hypothesis explaining firms' heterogeneity in a new industry with the concept of existent industry's technological trajectories, available assets, core processes and show the possibility of model to explain the heterogeneity of firms.

• Korea Journal of Hospital Management
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• v.24 no.3
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• pp.38-47
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• 2019

Purposes: Rapid aging and increase of high chronic diseases of the elderly are increasing the needs for expanding elderly care beyond the concept of treatment in medical institutions. This study is to discuss the core values, functions, and roles of municipal hospitals and suggest a suitable community care model. Methodology: The survey was collected twice derived from the domestic expert groups. This study analyzed experts' responses using Delphi method and Analytic Hierarchy Process, using Microsoft Excel 2016. Findings: Among the core values of the municipal hospitals, it was shown that community linkage had the highest priority. The publicity had the highest priority among the functions and roles of the municipal hospitals. In the community care models presented in this study, the model focused on 'Community Care Integration Center' showed highest relevance, suitability and applicability. Practical Implications: This study suggested three different community care models and derived the most suitable model for community care, which is focused on the municipal hospitals. It suggested effective application of the community care model to promote community care in each community.

• Nuclear Engineering and Technology
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• v.53 no.6
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• pp.1736-1746
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• 2021

The results of full-scale numerical experiments of a hybrid thorium-containing fuel cell facility operating in a close-to-critical state due to a controlled source of fusion neutrons are discussed in this work. The facility under study was a complex consisting of two blocks. The first block was based on the concept of a high-temperature gas-cooled thorium reactor core. The second block was an axially symmetrical extended plasma generator of additional neutrons that was placed in the near-axial zone of the facility blanket. The calculated models of the blanket and the plasma generator of D-T neutrons created within the work allowed for research of the neutronic parameters of the facility in stationary and pulse-periodic operation modes. This research will make it possible to construct a safe facility and investigate the properties of thorium fuel, which can be continuously used in the epithermal spectrum of the considered hybrid fusion-fission reactor.

• Nuclear Engineering and Technology
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• v.54 no.3
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• pp.877-887
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• 2022

A new reactor concept is described that directly couples a supercritical CO₂ (sCO₂) power cycle with a CO₂-cooled, heavy water moderated pressure tube core. This configuration attains the simplification and economic potential of past direct-cycle sCO₂ concepts, while also providing safety and power density benefits by using the moderator as a heat sink for decay heat removal. A 200 MWe design is described that heavily leverages existing commercial nuclear technologies, including reactor and moderator systems from Canadian CANDU reactors and fuels and materials from UK Advanced Gas-cooled Reactors (AGRs). Descriptions are provided of the power cycle, nuclear island systems, reactor core, and safety systems, and the results of safety analyses are shown illustrating the ability of the design to withstand large-break loss of coolant accidents. The resulting design attains high efficiency while employing considerably fewer systems than current light water reactors and advanced reactor technologies, illustrating its economic promise. Prospects for the design are discussed, including the ability to demonstrate its technologies in a small (~20 MWe) initial system, and avenues for further improvement of the design using advanced technologies.

• Nuclear Engineering and Technology
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• v.54 no.9
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• pp.3324-3335
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• 2022

Several countries show interest in the Generation-IV power reactor innovative small module (PRISM), including: Canada, Japan, Korea, Saudi Arabia and the United Kingdom. Generation IV International Forum (GIF) has recommended the utilizing of probabilistic safety assessment (PSA) in evaluating the safety of Generation-IV reactors. This paper reviews the PSA performed for PRISM using SAPHIRE 7.27 code. This work shows that the core damage frequency (CDF) of PRISM for a single module is estimated by 8.5E-8/year which is lower than the Generation-IV target that is 1E-6 core damage per year. The social risk of PRISM (likelihood of latent cancer fatality) with evacuation is estimated by 9.0E-12/year which is much lower than the basic safety objective (BSO) that is 1E-7/year. The social risk without evacuation is estimated by 1.2E- 11/year which is also much lower than the BSO. For the individual risk (likelihood of prompt fatality), it is concluded that it can be considered negligible with evacuation (1.0E-13/year). Assuming no evacuation, the individual risk is 2.7E-10/year which is again much lower than the BSO. In comparison with other PSAs performed for similar sodium fast reactors (SFRs), it shows that PRISM concept has the lowest CDF.

• International Journal of Advanced Culture Technology
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• v.11 no.2
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• pp.238-248
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• 2023

This study aims to examine the symbolism of the emblems of World Expositions by using Victor Turner's symbolic theory as a research method, and to reveal the symbolic types behind them by classifying the emblem designs of different periods and themes. The research object is 12 comprehensive World's Fair emblems from the 1939 New York World's Fair in the United States to the 2025 Osaka World's Fair in Japan, as identified by Bureau International des Expositions. The research method mainly adopts documentary research to collect historical information and theoretical frameworks related to the design of World's Fair emblems. In the analysis process, Victor Turner's symbolic sign theory is used as the main analytical framework to link the design elements of emblems to their relevance to specific societies and cultures in order to reveal the themes, values and ideas represented by the emblem symbolism. The results of the study show that the design of the Expo emblem uses different symbols, including material symbols, behavioral symbols, sensory symbols, natural symbols, social symbols and virtual symbols, to convey the core concepts, themes and values of the Expo. Through different types of symbols, the Expo emblem shows a wide range of concerns about technology and the future, mankind and the world, nature and ecology, and society and innovation. The symbolic design of the emblem plays an important role in conveying the core concept and theme of the Expo.