Verification of Accuracy and Calculation Efficiency of Global-Local Iterative Analysis Method for Large-scale Process-based TSPA

Hong Jang,Gil-Eon Jeong,Dong Hyuk Lee,Jung-Woo Kim 한국방사성폐기물학회 2023 한국방사성폐기물학회 학술논문요약집 Vol.21 No.1

The most important thing in development of a process-based TSPA (Total System Performance Assessment) tool for large-scale disposal systems (like APro) is to use efficient numerical analysis methods for the large-scale problems. When analyzing the borehole in which the most diverse physical phenomena occur in connection with each other, the finest mesh in the system is applied to increase the analysis accuracy. Since thousands of such boreholes would be placed in the future disposal system, the numerical analysis for the system becomes significantly slower, or even impossible due to the memory problem in cases. In this study, we propose a tractable approach, so called global-local iterative analysis method, to solve the large-scale process-based TSPA problem numerically. The global-local iterative analysis method goes through the following process: 1) By applying a coarse mesh to the borehole area the size of the problem of global domain (entire disposal system) is reduced and the numerical analysis is performed for the global domain. 2) Solutions in previous step are used as a boundary condition of the problem of local domain (a unit space containing one borehole and little part of rock), the fine mesh is applied to the borehole area, and the numerical analysis is performed for each local domain. 3) Solutions in previous step are used as boundary conditions of boreholes in the problem of global domain and the numerical analysis is performed for the global domain. 4) steps 2) and 3) are repeated. The solution derived by the global-local iterative analysis method is expected to be closer to the solution derived by the numerical analysis of the global problem applying the fine mesh to boreholes. In addition, since local problems become independent problems the parallel computing can be introduced to increase calculation efficiency. This study analyzes the numerical error of the globallocal iterative analysis method and evaluates the number of iterations in which the solution satisfies the convergence criteria. And increasing computational efficiency from the parallel computing using HPC system is also analyzed.

초등지리 교육과정에 반영된 세계시민교육 관련 요소의 구조적 특성에 관한 연구

이동민(Dong-min Lee) 대한지리학회 2014 대한지리학회지 Vol.49 No.6

본 연구의 목적은 현행 2009 개정 초등사회과 지리영역 교육과정에 반영된 세계시민교육 관련 요소의 구조적 특성을 분석하는데 있다. 분석대상으로는 세계에 관한 부분을 다룬 5~6학년군 지리영역 교육과정의 성취기준을 선정하였으며, 한글 텍스트의 내용분석을 위한 소프트웨어인 KrKwic 및 의미연결망 분석도구인 UciNet/NetDraw를 활용하여 관련 개념의 출현빈도 및 의미연결망, 연결중심성을 분석하였다. 분석 결과 2009 개정 초등사회과 지리영역 교육과정은 세계시민성 함양 등 세계시민교육의 이상과 요소를 반영하고는 있지만, 교육과정상의 세계에 대한 단원들은 세계나 세계공동체 등 세계시민교육 관련 요소보다는 주로 국가를 중심으로 구성되는 특성을 보이고 있었다. 세계시민교육 관련 요소는 교육과정 성취기준상에서의 출현빈도가 낮았을 뿐만 아니라, 세계와 관련된 주요 개념들과 밀접한 관계를 맺지 못한채 사실상 고립되다시피한 특성을 나타내었다. 이로 인해 환경 및 지속가능개발, 갈등, 협력 등 세계시민교육적으로 접근할 필요성이 높은 개념들 역시 세계시민교육적인 관점과 연결될 수 있는 가능성이 제한될 수 있다는 문제점도 지적된다. 세계화 시대에는 국가도 중요한 역할을 하지만, 기존의 국가 경계가 투과적인 형태로 변화하고 국경을 넘어선 세계공동체적 관점이 중요시되는만큼 지리교육 역시 이러한 현실을 감안하여 세계시민교육적 요소를 보다 적극적으로 반영할 필요성이 제기된다. 이러한 논의를 향후 교육과정 개정에 반영함으로써, 국가뿐만 아니라 세계공동체 또한 중요시되는 세계화 시대에 보다 높은 적합성을 갖는 교육과정을 구성할 수 있으리라고 기대된다. The purpose of this study is to analyze the share of global citizenship education in the 2009 Revised Social Studies (geography area) School Curriculum of the Republic of Korea. I selected the achievement standards of the geography domain in the fifth and sixth grades as the subjects of analysis. The chosen subjects were examined using content analysis: I used KrKwic, a Korean language content analysis tool, to analyze the content and drew a semantic network of the analysis results using UciNet/NetDraw. I found that the geography domain of the 2009 Revised Primary School Curriculum included the concepts of and factors of global citizenship education. However, global citizenship education did not account for a major portion of the curriculum, and the curriculum achievement standards were noticeably nation-state centered. Global citizenship education factors were not closely associated with to other related factors in fact, they even revealed a isolated pattern. These findings suggest that the inclusion of global citizenship education in primary geography education is limited, because the connections between global citizenship education and related contents, such as the environment, sustainable development, conflict, and cooperation, are probably impeded. Globalization accompanies the transformation of territories, identities, and the relations between nation-states and the world, although nation-states continue to play a significant role in the globalized worlds. Therefore global citizenship education, a educational trend focusing on the global community, is particularly important and is required in the geography curriculum of the global era. I expect that the examination undertaken in this study to contribute to future curriculum revisions regarding globalizatin and global citizenship.

The Methodological Expansion for Global City Analysis: From Principal Component Analysis and k-Means Clustering to Self-Organizing Map

손재선 한국도시지리학회 2019 한국도시지리학회지 Vol.22 No.1

Research for globalization and global cities has increased the variables on the catalog to explain globalization and global cities. This expansion of global city data requires a more efficient method which can simplify the process and understand analysis intuitively. The purpose of this study is to test a new SOM (self-organizing map) as an addition to global cities analytic methods comparing to the traditional method based on principal component analysis and k-means clustering. Most available 15 attributes for 75 global cities are collected for the research purpose. The principal component analysis found 4 factors, and global cities are classified into 5 types by k-means clustering. The self-organizing map analyzed the same data and visualized the clusters on U-matrix (unified distance matrix) and the patterns of the input attributes on component planes. Compared to the traditional process of data reduction, the SOM effectively visualize common attributes on component planes preserving the topological properties so that it is easy to analyze the relationship between attributes and cities. However, the outputs of the case classification are different from the outputs of the traditional methods. Most importantly, the SOM provides data-driven research with fewer decisions made by analysts than the traditional process.

Still a Valid Unit of Analysis? : Globalization and the State in Comparative Political Analysis

Joo-Youn Jung(정주연) 고려대학교 일민국제관계연구원 2012 국제관계연구 Vol.17 No.1

'세계화'로 요약되는 정치·경제적인 제도와 규범의 확산과 국가들 간의 경제적인 상호의존 심화는, 국가를 주요한 분석단위로 삼아 온 비교정치연구에 심각한 도전이 될 수 있다. 이 논문은 세계화가 가속화되는 상황에서 여전히 국가가 유효한 분석단위인가를 방법론적, 경험론적으로 분석한다. 이 논문은 분석단위로서의 국가에 대한 도전은 새로운 것이지도, 치명적인 것이지도 않으며, 오히려 세계화가 국가의 역할과 방법론적인 비교 분석단위로서의 위상을 재조명하게 해 준다고 주장한다. Globalization poses potential challenges to comparative political analysis based on the state as the primary unit of analysis. When the diffusion of universal political and economic institutions, ideas, and norms across borders occurs the basis for comparison might be lost because the units being compared are not separate instances of the phenomenon we wish to study. Nor is it reasonable to make the conventional assumption that a country's political institutions and policy outputs result primarily from the interplay of forces within that country. Under the pressures of neoliberal marketization, the state's policymaking autonomy and command over its territory is asserted to be considerably undermined as well. This paper analyzes the methodological and empirical challenges that globalization has posed on the state as a unit of analysis, and argues that the "challenges" are neither new nor fatal. The challenges have enabled the state to reinforce its capacity and brought the comparative scholarly interest back to the state.

변절점 다면체 유한요소를 이용한 h 및 p 격자세분화 전역국부해석

임재혁,손동우,김성훈 한국항공우주학회 2014 한국항공우주학회 학술발표회 논문집 Vol.2014 No.11

본 논문에서는 변절점 다면체 유한요소를 이용한 h 및 p 격자세분화 전역국부해석기법에 대해 기술한다. 변절점 다면체 유한요소는 임의의 수의 절점과 형상을 가질 수 있는 유한요소로 많은 수의 다른 근사차수를 갖는 유한요소 간의 결합을 벌칙함수나 라그랑지승수의 도움 없이 손쉽고 정확하게 수행해낸다. 이를 전역국부해석에 적용하면, 국부영역에 상세한 구조해석을 위해 사용되는 하중 및 변위경계조건을 전역해석 결과로부터 보간기법의 도움을 받지 않고 구해낼 수 있다. 또한 이 하중 및 변위장을 이용해서 h 및 p 격자세분화 국부해석을 실시하면 정밀한 유한요소해석을 수행하는 것이 가능하다. 제안된 방법의 우수성을 보여주기 위해 다양한 수치예제를 해석하고 검증하였다. In this work, an h- and p-refined global-local analysis using variable-node polyhedral elements is introduced for accurate stress evaluation. The variable-node polyhedral elements can have an arbitrary number of elements on their faces and edges, which provide a simple and accurate connection between two dissimilar meshes with different resolutions or interpolation orders without introducing additional variables or parameters such as Lagrange multiplier and penalty function parameter. In case of global-local analysis, for the detailed local analysis, the interpolation for generating a fine displacement/force field from the solution of global analysis with coarse resolution leads to an error. In the proposed scheme, it eliminates a faulty interpolation procedure with the aid of variable-node polyhedral elements. Furthermore, an h- and p-refined global-local analysis can be conducted in a straightforward manner. To demonstrate the performance of the proposed scheme, several numerical examples have been treated.

Evaluation of sloshing resistance performance for LNG carrier insulation system based on fluid-structure interaction analysis

이치승,조진래,김화수,노병재,김명현,이제명 대한조선학회 2013 International Journal of Naval Architecture and Oc Vol.5 No.1

In the present paper, the sloshing resistance performance of a huge-size LNG carrier’s insulation system is evaluated by the fluid-structure interaction (FSI) analysis. To do this, the global-local analysis which is based on the arbitrary Lagrangian-Eulerian (ALE) method is adopted to accurately calculate the structural behavior induced by internal LNG sloshing of a KC-1 type LNG carrier insulation system. During the global analysis, the sloshing flow and hydrodynamic pressure of internal LNG are analyzed by postulating the flexible insulation system as a rigid body. In addition, during the local analysis, the local hydroelastic response of the LNG carrier insulation system is computed by solving the local hydroelastic model where the entire and flexible insulation system is adopted and the numerical analysis results of the global analysis such as initial and boundary conditions are implemented into the local finite element model. The proposed novel analysis techniques can potentially be used to evaluate the structural integrity of LNG carrier insulation systems.

A retrospective evaluation of the intellectual structure of private agricultural and food standards research in global trade

Lwesya Francis,Mbukwa Justine 경희대학교 글로벌 통상·금융연구원 2023 International Trade, Politics and Development Vol.7 No.2

The aim of this article was to present a retrospective assessment of the intellectual structure of private agricultural and food standards research in global trade. This study was motivated by the increasing role of standards and certifications in governing global agricultural and food trade.The current investigation was carried out with bibliometric methods using VOSviewer software. Techniques such as citation, co-citation, keyword co-occurrence, keyword evolution and co-authorship analyses were performed to tackle the research questions. Articles were extracted from Scopus database for the period 1998–2022 (30th August 2022) with selected keywords (“Private food standard*” OR “food standard*” OR “agri-food standard*” AND “agri*” OR “agro*” OR “farm*” OR “food*” AND “international trade” OR “global trade” OR “international business”) along certain filters (subject – Economics and Business management: language – English: Document – article and review articles and source – journals).The results show that the intellectual structure of private agricultural and food standards research in global trade has evolved around five clusters, namely: (1) the political economy of food standards, (2) food standards and their challenges in global trade, (3) food standards and integration into value chains, (4) food standards and market access and (5) food standards and exports from developing countries. However, the authors found the research gaps in each of the thematic clusters.The main limitation of this study is that the authors focused their attention on certain aspects of bibliometric review, such as the intellectual structure of the field, the citation analysis and the collaboration network. Future research could attempt to explore new field development through bibliographic coupling and deepening of conceptual structure using content analysis by incorporating the research methods used in the respective studies.The emerging research areas in private agricultural and food standards in global trade are related to topics on food quality, sustainable development, genetically modified organisms, World Trade Organization, tariff structure, trade agreements, food industry and European Union. However, there is less research and little collaboration between Africa and developed countries. For example, Africa's total publications were (15), while the US had (46), China (15), Belgium (23), Germany (27), Italy (32) and the UK (24).There are limited studies that have conducted a retrospective evaluation of the intellectual structure of private agricultural and food standards research in the global trade using bibliometric analysis. The present investigation is novel in identifying the thematic research clusters, emerging issues and future research directions. This is more important to developing countries as their agricultural produce face challenges to access markets of the developed world.

세계시민성에 영향을 미치는 학교 특성 분석: 초․중․고 학교급 별 교사의 인식을 중심으로

이성회(Sunghoe Lee),윤지영(Jiyoung Yoon) 학습자중심교과교육학회 2017 학습자중심교과교육연구 Vol.17 No.11

본 연구는 교사들이 인식하는 학생의 세계시민성에 영향을 미치는 학교 특성을 분석하고자 하였다. 이를 위해 학교 특성을 교사 특성, 학교의 일반적 특성, 학교 문화로 나누었으며, 학교에 따른 영향 요인을 다층모형을 사용하여 확인하였다. 그 결과, 교사는 세계시민교육의 필요성을 인식하고, 지도역량을 가지고 있다고 응답할 수록 학생의 세계시민성도 높다고 인식하였다. 학교급에 따라 중학교 교사들은 초등, 고등학교 교사에 비해 학생들의 세계시민성이 떨어진다고 하였으며, 전반적인 학교 문화에 세계시민교육이 반영되어 있거나, 특정 프로그램 또는 학교 행사로 실시하는 학교는 학생들의 세계시민성이 높다고 보고하였다. 학교급 별 영향요인 검증결과, 중·고등학교에 비해 초등학교는 유네스코학교일수록, 고등학교에서는 학교 행사로라도 세계시민교육을 한다면, 학생의 세계시민성이 높다고 인식하였다. 본 연구는 지금까지 선행 연구에서 간과되었던 초등학교와 중등학교의 데이터를 모두 포괄한 실증적 데이터를 제공함과 동시에, 학교급에 따라 학생들의 세계시민성에 영향을 미치는 학교 특성을 확인하였다는 점에서 그 의의가 있다. This study analysed the effect of school characteristics on the teachers perception of students’ global citizenship using multilevel analysis. The school characteristics included teacher characteristics, the general characteristics of schools, and school ethos. The results show that the more teachers perceive the necessity of global citizenship education and the more they have confidence in their ability to teach it, the higher did they perceive students’ level of global citizenship. Regarding school characteristics, comparing to the students in elementary and high schools, those in middle schools showed lower level of global citizenship. Schools with lower percentages of free after-school vouchers (less than 10%) and with membership of UNESCO associated schools project network showed higher level of students’ global citizenship. Furthermore, schools that have school ethos of integrating global citizenship education through whole school activities are likely to have students with higher level of global citizenship. This study is original in that it demonstrates empirical analysis encompassing both primary and secondary schools and the effect of school characteristics on the students’ global citizenship according to school levels, which is a neglected scholarly issue in the existing literature.

Evaluation of sloshing resistance performance for LNG carrier insulation system based on fluid-structure interaction analysis

Lee, Chi-Seung,Cho, Jin-Rae,Kim, Wha-Soo,Noh, Byeong-Jae,Kim, Myung-Hyun,Lee, Jae-Myung The Society of Naval Architects of Korea 2013 International Journal of Naval Architecture and Oc Vol.5 No.1

In the present paper, the sloshing resistance performance of a huge-size LNG carrier's insulation system is evaluated by the fluid-structure interaction (FSI) analysis. To do this, the global-local analysis which is based on the arbitrary Lagrangian-Eulerian (ALE) method is adopted to accurately calculate the structural behavior induced by internal LNG sloshing of a KC-1 type LNG carrier insulation system. During the global analysis, the sloshing flow and hydrodynamic pressure of internal LNG are analyzed by postulating the flexible insulation system as a rigid body. In addition, during the local analysis, the local hydroelastic response of the LNG carrier insulation system is computed by solving the local hydroelastic model where the entire and flexible insulation system is adopted and the numerical analysis results of the global analysis such as initial and boundary conditions are implemented into the local finite element model. The proposed novel analysis techniques can potentially be used to evaluate the structural integrity of LNG carrier insulation systems.

A Study on the Structural Changes of Cashew Nut’s Global Trade Network: Focused on Vietnam

Thi Chinh Vo,Seong-Tae Ji 한국무역연구원 2021 무역연구 Vol.17 No.1

Purpose This paper aims to analyze the structural changes of cashew nut’s global trade network due to changes in the supply and demand of cashew nuts in Vietnam using the degree centrality index and visualizing them. Design/Methodology/Approach This paper analyzes the global cashew nut trade network based on the Degree Centrality;Betweenness Centrality;and Closeness Centrality indexes of Social Network Analysis. The 2000-2009 trade data from the UN Comtrade database was used;and the 2000-2009 and 2010-2019 data were analyzed separately;assuming that Vietnam’s cashew nuts production structure changed around 2010. Findings With Vietnam’s recent decline in cashew nuts production;Vietnam’s index (weighted) was the largest in the in-shell cashews In-degree Centrality and the shelled cashews Out-degree Centrality analysis in 2010-2019. It means that Vietnam’s influence in the global cashew nuts network has been increased compared to that in 2000-2009 due to increased trade volume and partner countries. Moreover;Betweenness Centrality and Closeness Centrality index shows that Vietnam’s ability to control the flow of cashew nuts exports and imports and its ability to adapt and react to changes in the global cashews market has been enhanced compared to the past. Research Implications Vietnam was the world’s largest producer of cashew nuts;processing and exporting its domestic produced cashew nuts. However;with the recent decline in domestic production;in-shell cashew nuts have been imported from African countries such as Côte d’Ivoire. So;a new global food value chain was formed by processing and exporting them. It means a change in Vietnam’s cashew nuts industry structure and a new South-South cooperation model in the agricultural sector. In other words;developing countries can form a global value chain in the agricultural sector and be mutually win-win.