• Title/Summary/Keyword: growth modeling

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Geospatial Analysis and Modeling in Korea: A Literature Review (한국의 지리공간분석 및 모델링 연구)

  • Lee, Sang-Il;Kim, Kam-Young
    • Journal of the Korean Geographical Society
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    • v.47 no.4
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    • pp.606-624
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    • 2012
  • The main objective of this paper is to provide an adequate and comprehensive review of what has been done in South Korea in the field of geospatial analysis and modeling. This review focuses on spatial data analysis and spatial statistics, spatial optimization, and geosimulation among various aspects of the field. It is recognized that geospatial analysis and modeling in South Korea got through the initial stage during the 1990s when computer and analytical cartography and GIS were introduced, moved to the growth stage during the first decade of the $21^{st}$ century when there was a surge of relevant researches, and now is heading for its maturity stage. In spatial data analysis and spatial statistics, various topics have been addressed for spatial point pattern data, areal data, geostatistical data, and spatial interaction data. In spatial optimization, modeling and applications related to facility location problems, districting problems, and routing problems have been mostly researched. Finally, in geosimulation, while most of research has focused on cellular automata, studies on agent-based model and simulation are in beginning stage. Among all these works, some have fostered methodological advances beyond simple applications of the standard techniques.

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Mathematical Modeling and Analysis for Water_Tree of Underground Cables (지중 케이블의 수트리에 대한 수학적 모델링 및 분석)

  • Lee, Jung-Woo;Oh, Yong-Taek
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.5
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    • pp.516-522
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    • 2020
  • Water trees can cause considerable damage to the performance of underground cables. Theymay formwithin the dielectric used in buried or water-immersed high voltage cables. They grow in a bush-like or tree-like form, often taking decades before causing damage to a cable's performance. They are usually found on very old underground cables, often in an inaccessible place. It is costly and time-consuming to detect watertrees in underground cables. Tree detection technology, including mathematical modeling,can reduce the maintenance cost and time necessary for detecting these trees.To simulate detection of water trees in this study, a mathematical model ofan XLPE cable and a water tree were developed. The complex water tree structure was simplified, based on two identified patterns of aventedtree. A Matlab simulation was performed to calculate and analyze the capacitance and resistance of a cable insulation layer,based on growth of a watertree. Capacitance size increased about 0.025×10-13[Farads/mm] compared to normal when the tree area of the cable was advanced to 95% of the insulation layer. The resistance value decreased by about 0.5×1016[ohm/m]. These changesand changesshowninaBurkes paper physical modeling simulation are similar.The value of mathematical modeling for detecting water trees and damage to underground cables has been demonstrated.

Topic Modeling-Based Domestic and Foreign Public Data Research Trends Comparative Analysis (토픽 모델링 기반의 국내외 공공데이터 연구 동향 비교 분석)

  • Park, Dae-Yeong;Kim, Deok-Hyeon;Kim, Keun-Wook
    • Journal of Digital Convergence
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    • v.19 no.2
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    • pp.1-12
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    • 2021
  • With the recent 4th Industrial Revolution, the growth and value of big data are continuously increasing, and the government is also actively making efforts to open and utilize public data. However, the situation still does not reach the level of demand for public data use by citizens, At this point, it is necessary to identify research trends in the public data field and seek directions for development. In this study, in order to understand the research trends related to public data, the analysis was performed using topic modeling, which is mainly used in text mining techniques. To this end, we collected papers containing keywords of 'Public data' among domestic and foreign research papers (1,437 domestically, 9,607 overseas) and performed topic modeling based on the LDA algorithm, and compared domestic and foreign public data research trends. After analysis, policy implications were presented. Looking at the time series by topic, research in the fields of 'personal information protection', 'public data management', and 'urban environment' has increased in Korea. Overseas, it was confirmed that research in the fields of 'urban policy', 'cell biology', 'deep learning', and 'cloud·security' is active.

Combined Extended and Superimposed Finite Element Method for Crack Analysis (균열해석을 위한 겹침확장 유한요소법)

  • 이상호;송정훈;허문석
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2004.04a
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    • pp.341-348
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    • 2004
  • This paper presents a modeling technique of cracks by combined extended and superposed finite element method (XSFEM) which is a combination of the extended finite element method (XFEM) and the mesh superposition method (sversion FEM). In the proposed method, the near-tip field is modeled by a superimposed patch consisting of quarter point elements and the rest of the discontinuity is treated by the XFEM. The actual crack opening in this method is measured by the sum of the crack openings of XFEM and SFEM in transition region. This method retains the strong point of the XFEM so it can avoid remeshing in crack evolution and trace the crack growth by translation or rotation of the overlaid mesh and the update of the nodes to be enriched by step functions. Moreover, the quadrature of the Galerkin weak form becomes simpler. Numerical experiments are provided to demonstrate the effectiveness and robustness of the proposed method.

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The Development of Automated Building Equipment Design Process System Using 3D CAD (3차원 CAD정보를 활용한 건축설비설계 프로세스 시스템 개발방향)

  • Lee, Dong-Hyun;Jung, Woo-Shin;Kim, Young-Don;Song, Kyoo-Dong
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2008.04a
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    • pp.269-274
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    • 2008
  • It is attempted that the standardization of the construction, globalization of the engineering construction and an information oriented construction spread by setting a goal of the advanced construction industry and productivity increase of human resources within the country. Hence, it has been brought in the information oriented construction of BIM based technology for the field of construction and equipment of Korea. The current study that examines the possibility of application of 3D ; that is BIM based programs of building equipment, and make better the problems of 3D building equipment system through the Pilot Test, indicates the way of growth development about the construction of building equipment process system.

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Assessment of electricity demand at domestic level in Balochistan, Pakistan

  • Urooj, Rabail;Ahmad, Sheikh Saeed
    • Advances in Energy Research
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    • v.5 no.1
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    • pp.57-64
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    • 2017
  • Electricity is basic need for country development. But at the present time proper planning and policy is require at high pace for power generation network extension due to the increasing population growth rate. Present study aimed to analyze the present and future demand for electricity at household level in Province of Balochistan of Pakistan via simulation modeling. Data of year 2004-2005 was used as baseline data for electricity consumption to predict future demand of electricity at both rural and urban domestic level up to subsequent 30 years, with help of LEAP software. Basically three scenarios were created to run software. One scenario was Business-As-Usual and other two were green scenarios i.e., solar and wind energy scenarios. Results predicted that by using alternative energy sources, demand for electricity will be fulfill and will also reduce burden on non-renewable energy sources due to the greater potential for solar and wind energy present in Balochistan.

Prediction of the Behavior of dynamic Recrystallization in Inconel 718 during Hot Forging using Finite Element Method (유한요소법을 이용한 Inconel 718의 열간단조공정시 동적재결정거동 예측)

  • Choi, Min-Shik;Kang, Beom-Soo;Yum, Jong-Taek;Park, Noh-Kwang
    • Transactions of Materials Processing
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    • v.7 no.3
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    • pp.197-206
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    • 1998
  • This paper presents the prediction of dynamic recrystallization behavior during hot forging of Inconel 718. Another experiment of pancake forging was also carried out to examine the recrystallization ration dynamically recrystallizaed grain size, and grain growth in the forging. In experiments cylindrical billets were forged by two operations with variations of forging temperature, reduction ration of deformation. and preheating process at each forging step. Also the finite element program, developed here for the prediction using the metallurgical models was used for the analysis of to Inconel 718 upsetting and the results were compared with experimental ones.

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Modeling on the Nonlinear Rate Sensitivity of Flow Stress (유동응력의 비선형 속도 민감도에 대한 모델링)

  • Ho, Kwang-Soo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.28 no.6
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    • pp.670-676
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    • 2004
  • Most metallic materials and alloys show rate independence or negative rate sensitivity in some temperature region when dynamic strain aging occurs. It is generally recognized that negative rate sensitivity is an essential feature of dynamic strain aging that can depend on strain and/or strain rate. The unified viscoplasticity theory based on overstress is applied to reproduce a change of rate sensitivity type that depends on strain or strain rate. This is accomplished through the introduction of a single new term in the growth law of the equilibrium stress, which is a tensor valued state variable of the model. It is also shown that the new term can be used to reproduce a dramatic increase of rate sensitivity in dynamic plasticity.

Dynamic Modeling of the Korean Nuclear Euel Cycle

  • Jeong, Chang-Joon;Park, Joo-Hwan;Park, Hangbok
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2004.06a
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    • pp.386-395
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    • 2004
  • The Korean fuel cycle scenario has been modeled by using the dynamic analysis method. For once-through fuel cycle model, the nuclear power plant construction plan was considered, and the nuclear demand growth rate from the year 2016 was assumed to be 1%. After setup the once-thorough fuel cycle model, the DUPIC and fast reactor scenarios were modeled to investigate the environmental effect of each fuel cycle. Through the calculation of the amount of spent fuel, and the amounts of plutonium and minor actinides were estimated and compared to those of the once-through fuel cycle. The results of the once-through fuel cycle shows that the demand grows to 64 GWe and the total amount of the spent fuel would be 100 kt in the year 2100, while the total spent fuel can be reduced by 50% when the DUPIC scenario is implemented

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The Five-year Developmental Trajectories of Perceived Stress and Depression in Korean Youth (초등학생 아동의 스트레스와 우울의 5년에 걸친 발달적 변화)

  • Park, Mi Hyun;Park, Kyung Ja;Kim, Hyoun K.
    • Korean Journal of Child Studies
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    • v.33 no.4
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    • pp.1-17
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    • 2012
  • This study examined the developmental trajectories of perceived level of stress and depression in Korean youth using longitudinal data from the Korean Youth Panel Study (KYPS) of 2,844youth (1,524 boys) across $4^{th}$ grade through $8^{th}$ grade. Latent growth modeling indicated the presence of age-related, significant increases in stress and depression for both boys and girls. Girls experienced greater in stress and depression than did boys. Multiple group analysis indicated that there was no significant sex difference in effects of stress on depression. Overall, increases in stress were associated with increases in depression levels for both boys and girls. Conceptual and clinical implications of the findings were discussed.