• Title/Summary/Keyword: core concept

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Dry storage of spent nuclear fuel and high active waste in Germany-Current situation and technical aspects on inventories integrity for a prolonged storage time

  • Spykman, Gerold
    • Nuclear Engineering and Technology
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    • v.50 no.2
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    • pp.313-317
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    • 2018
  • Licenses for the storage of spent nuclear fuel (SNF) and vitrified highly active waste in casks under dry conditions are limited to 40 years and have to be renewed for prolonged storage periods. If such a license renewal has to be expected since as in accordance with the new site selection procedure a final repository for spent fuel in Germany will not be available before the year 2050. For transport and possible unloading and loading in new casks for final storage, the integrity and the maintenance of the geometry of the cask's inventory is essential because the SNF rod cladding and the cladding of the vitrified highly active waste are stipulated as a barrier in the storage concept. For SNF, the cladding integrity is ensured currently by limiting the hoop stress and hoop strain as well as the maximum temperature to certain values for a 40-year storage period. For a prolonged storage period, other cladding degradation mechanisms such as inner and outer oxide layer formation, hydrogen pick up, irradiation damages in cladding material crystal structure, helium production from alpha decay, and long-term fission gas release may become leading effects driving degradation mechanisms that have to be discussed.

An Analysis of Critical Heat Flux on the External Surface of the Reactor Vessel Lower Head

  • Yang, Soo-Hyung;Baek, Won-Pil;Chang, Soon-Heung
    • Proceedings of the Korean Nuclear Society Conference
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    • 1999.10a
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    • pp.190-190
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    • 1999
  • CHF (Critical heat flux) on the external surface of the reactor vessel lower head is major key in the evaluation on the feasibility of IVR-EVC (In-Vessel Retention through External Vessel Cooling) concept. To identify the CHF on the external surface, considerable works have been performed. Through the review on the previous works related to the CHF on the external surface, liquid subcooling, induced flow along the external surface, ICI (In-Core Instrument) nozzle and minimum gap are identified as major parameters. According to the present analysis, the effects of the ICI nozzle and minimum gap on CHF are pronounced at the upstream of test vessel: on the other hand, the induced flow considerably affects the CHF at downstream of test vessel. In addition, the subcooling effect is shown at all of test vessel, and decreases with the increase in the elevation of test vessel. In the real application of the IVR-EVC concept, vertical position is known as a limiting position, at which thermal margin is the minimum. So, it is very important to precisely predict the CHF at vertical position in a viewpoint of gaining more thermal margins. However, the effects of the liquid subcooling and induced flow do not seem to be adequately included in the CHF correlations suggested by previous works, especially at the downstream positions.

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Fluidic Thrust Vector Control Using Shock Wave Concept (충격파 개념에 기반한 유체 추력벡터제어에 관한 연구)

  • Wu, Kexin;Kim, Heuy Dong
    • Journal of the Korean Society of Propulsion Engineers
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    • v.23 no.4
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    • pp.10-20
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    • 2019
  • Recently, fluidic thrust vector control has become a core technique to control multifarious air vehicles, such as supersonic aircraft and modern rockets. Fluidic thrust vector control using the shock vector concept has many advantages for achieving great vectoring performance, such as fast vectoring response, simple structure, and low weight. In this paper, computational fluid dynamics methods are used to study a three-dimensional rectangular supersonic nozzle with a slot injector. To evaluate the reliability and stability of computational methodology, the numerical results were validated with experimental data. The pressure distributions along the upper and lower nozzle walls in the symmetry plane showed an excellent match with the test results. Several numerical simulations were performed based on the shear stress transport(SST) $k-{\omega}$ turbulence model. The effect of the momentum flux ratio was investigated thoroughly, and the performance variations have been clearly illustrated.

Social Accountability of Medical Schools: Concept and Implementation Strategies (의과대학의 사회적 책무성: 개념과 실천전략)

  • Gil, Yoon Min;Jeon, Woo Taek
    • Korean Medical Education Review
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    • v.21 no.3
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    • pp.127-136
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    • 2019
  • Medical schools have been working to produce competent doctors and improve the quality of care by introducing and implementing new curricula and innovative teaching and learning methods. Despite these efforts, health disparities within and between countries still exist. To close these gaps, medical schools must identify the priorities of the community, region, and/or nation and conduct education, research, and service that reflect them-the core foundation of the social accountability of medical schools. Many medical schools and networks around the world have tried to achieve social accountability, but this needs more attention in Korea. This study will review the literature in aims to improve understanding and promote the implementation of the social accountability of medical schools. Most medical schools that practice the principles of social accountability focus primarily on the medically underserved in their communities or those who have limited access to health services, and have built collaborative partnerships with stakeholders to meet the needs of society. In addition, in order to implement social accountability effectively and efficiently, medical schools have developed strategies and various evaluation frameworks appropriate to the context of each school. To have more socially accountable medical schools, it is necessary to clarify the concept of social accountability and to establish a system that can evaluate the impacts. Medical schools exist to alleviate suffering and promote health, and this can be accomplished through social accountability.

The Concept of Academic Medicine and Its Potential Establishment in Korea (학술의학(Academic Medicine)의 개념과 한국에서의 정착 가능성)

  • Han, Hee Chul
    • Korean Medical Education Review
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    • v.21 no.2
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    • pp.63-72
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    • 2019
  • The purpose of this study was to introduce the concept of academic medicine to the medical societies of Korea and to identify any potential obstacles in the establishment of academic medicine in Korea. The core concepts of academic medicine include medical education, research, and patient care. Academic medicine can be practiced in the unique area of healthcare involving medical schools and teaching hospitals by faculty physicians in the academic medicine field. Through academic medicine, the next generation of healthcare professionals is trained, new discoveries can be made, and patients can find new hope for a cure. The flourishing of academic medicine has resulted in substantial advancements in medicine over the past few centuries, but at the turn of the 21st century, there was concern that academic medicine was on the decline. To address this concern, the International Campaign to Revitalize Academic Medicine was established and announced five scenarios to 2025 to debate the future of academic medicine. Although the system resembles that of Western medical societies, Korean medical societies were not familiar with academic medicine, and poor conditions caused by the distorted healthcare system in Korea have actually interfered with the nurturing of academic medicine. One of the main problems may include less interest in medical education and research relative to clinical practice by medical societies and the government. Collaborative efforts from both medical societies and the government are needed to establish academic medicine successfully in Korea for a better future.

Digital Fabrication Integrated Architectural Design Process based on Lean startup (Lean startup 방법을 적용한 디지털 패브리케이션 통합 건축 설계 프로세스)

  • Jung, Jae-hwan;Kim, Sung-Ah
    • Journal of KIBIM
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    • v.8 no.4
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    • pp.23-33
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    • 2018
  • Recently, the industry actively adopts the cutting-edge technologies of the fourth industrial revolution and uses them to enhance the productivity and service of mass-customization. The manufacturing industry is creating new processes and business models by achieving digital transformations through a lean start-up approach aimed at achieving the highest customer satisfaction with minimal resources. Although attempts are made to manufacture the building by introducing the latest technology in architecture, it is applied sporadically, not as an integrated system, in the entire phase of the architectural project. This paper analyzes the changes in the construction industry through the application of core technologies of the fourth industrial revolution. Design processes are analyzed for the digital transformation of the construction industry by case study of advanced architectural design practice. A novel design concept model 'Architectural lean startup' is proposed by combining the architectural process and the lean start up method. Through the design of the bus stop based on the architectural lean startup concept, it is confirmed that the designer repeats the 'Generate-Test-Analysis' to develop the design and generate the final result.

Safety-II and Resilience Engineering in a Nutshell: An Introductory Guide to Their Concepts and Methods

  • Ham, Dong-Han
    • Safety and Health at Work
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    • v.12 no.1
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    • pp.10-19
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    • 2021
  • Background: Traditional safety concept, which is called Safety-I, and its relevant methods and models have much contributed toward enhancing the safety of industrial systems. However, they have proved insufficient to be applied to complex socio-technical systems. As an alternative, Safety-II and resilience engineering have emerged and gained much attention for the last two decades. However, it seems that safety professionals have still difficulty understanding their fundamental concepts and methods. Accordingly, it is necessary to offer an introductory guide to them that helps safety professionals grasp them correctly in consideration of their current practices. Methods: This article firstly explains the limitations of Safety-I and how Safety-II can resolve them from the four points of view. Next, the core concepts of resilience engineering and Functional Resonance Analysis Method are described. Results: Workers' performance adjustment and performance variability due to it should be the basis for understanding human-related accidents in socio-technical systems. It should be acknowledged that successful and failed work performance have the same causes. However, they are not well considered in the traditional safety concept; in contrast, Safety-II and resilience engineering have conceptual bases and practical approaches to reflect them systematically. Conclusion: It is necessary to move from a find-and-fix and reactive approach to a proactive approach to safety management. Safety-II and resilience engineering give a set of useful concepts and methods for proactive safety management. However, if necessary, Safety-I methods need to be properly used for situations where they can still be useful as well.

Values and Concepts for the Establishment of Korean Vegetarianism: A Focus on the Historical Development of the Vegetarian Movement (베지테리언 음식으로서 한식의 가치와 개념 정립을 위한 제언 - 채식주의 운동의 역사적 전개과정을 중심으로 -)

  • Chae-Lin, Park
    • Journal of the Korean Society of Food Culture
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    • v.37 no.6
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    • pp.467-476
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    • 2022
  • This article defines the characteristics of Korean vegetarianism by tracing the changes in the core motives revealed in the historical development of the vegetarian movement that started in the West. We further explore and compare the limitations of the vegetarian movement conceived in the West with the essential values, 'How can Korean vegetarian culture gain the upper hand?'. Our results indicate that the sequential changes of the motives inherent to the flow of the modern vegetarian movement were <religious-philosophy>, <political-society>, and <healthy-nutrition>. This settled the transition from 'vegetarianism as an ideological form' to 'vegetarianism as a lifestyle', making it a more becoming way of life. However, along with the spread of 'vegetarian lifestyle as a form of life', commercial vegetarianism, which overshadows the essential value of vegetarianism, continued to flourish due to the modern capitalist industrial system. To curb commercialization, the necessity arose to establish a new vegetarian diet with a propensity towards an 'ecological-environmental point of view'. Thus, in order to establish the term and concept of a vegetarian diet for Korean vegetarian characteristics, we propose the formation of a vegetarian term and concept suitable for the Korean vegetarian culture.

A Study of Smart Convergence Strategies for Enhancing a Creative Economy: Lessons from Korea (창조경제 활성화를 위한 스마트융합 전략방안)

  • Kim, Yong-Beom;Kwak, Jeongho
    • Journal of Internet Computing and Services
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    • v.15 no.4
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    • pp.67-79
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    • 2014
  • One of the core policies recently implemented by the Korean government is the introduction of a creative economy, a concept that integrates ICT with the existing economic structure in order to create new growth factors and jobs. In June of 2013, the National Assembly passed a bill for the institutional practice of a creative economy. The concept of a creative economy is to integrate industries centered on ICT in order to form a new-concept industry paradigm that creates new values and services that exceed past industrial categories. In other words, smart convergence, which integrates ICT with various industries, is evaluated as a core factor for boosting the creative economy. Thus, based on the definition of 'smart convergence', this study predicted the economic effects and sociocultural changes that will ensue due to the future era of smart convergence. Also, this study proposes policies for enhancing the creative economy in various ways. More specifically, in-depth interviews with convergence industry experts were carried out and quantitative analyses were performed employing a Solow Model. Furthermore, as a means to revitalize the creative economy, this study underscores the significance of the preemptive institutionalization of legislations and suggests several policy proposals regarding smart convergence rooted in market supply and the demand chain, smart convergence through selective focus, and smart work. This study is differentiated from previous studies that have only focused in establishing theories in that it offers quantitative research with a consideration of the feasibility of proposed policies. The leading experience of Korea regarding smart convergence can provide important lessons to other countries that hope to promote a creative economy as a means to create new growth factors and jobs.

An Analysis and Implications Exploration of Media and Information Literacy (MIL) Curriculum in the Philippines (필리핀의 미디어정보 리터러시 교육과정 분석과 시사점 탐색)

  • Park, Juhyeon
    • Journal of Korean Library and Information Science Society
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    • v.52 no.2
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    • pp.331-355
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    • 2021
  • The purpose of this study is to derive the implications of operating the Media and Information Literacy (MIL) curriculum in Korea through analysis of MIL curriculum and guidance in the Philippines. The Philippine Ministry of Education runs the MIL as a core subject that high school students in grades 2-3 had to complete. MIL in the Philippines is a tool curriculum that integrates information, media, and digital literacy. In the MIL curriculum, a total of 17 units are designed to be operated for a total of 80 hours, 20 weeks in a semester. And it presents two content criteria, two achievement criteria and 58 learning competencies. The implications drawn from the research results are as follows. First, the chapter presented in the MIL curriculum can be composed only of the knowledge of a higher category or core concept of subject content. Second, it is necessary to present the concept of the term used in the MIL curriculum and specific examples according to the concept. Third, it is necessary to specify the contents necessary for practice in the MIL textbook and to strengthen the competence for the function. MIL, proposed by UNESCO and designated and operated as a subject in the Philippines, needs to be designated as a subject in Korea and operated as a curriculum.