• Journal of Electrical Engineering and Technology
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• v.12 no.4
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• pp.1548-1555
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• 2017

This paper attempts to employ and investigate neural based approaches as interpolation tools for modeling of Switched Reluctance Motor (SRM) drive. Precise modeling of SRM is essential to analyse the performance of control strategies for variable speed drive application. In this work the suitability of Generalized Regression Neural Network (GRNN) and Extreme Learning Machine (ELM) in addition to conventional neural network are explored for improving the modeling accuracy of SRM. The neural structures are trained with the data obtained by modeling of SRM using Finite Element Analysis (FEA) and the trained neural network is incorporated in the model of SRM drive. The results signify the modeling accuracy with GRNN model. The closed loop drive simulation is performed in MATLAB/Simulink environment and the closeness of the results in comparison with the experimental prototype validates the modeling approach.

• Korean Chemical Engineering Research
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• v.44 no.6
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• pp.579-587
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• 2006

Recently, each country has been trying to promote Eco-Industrial Park (EIP) development for industrial sustainability. Technological modeling is required to realize EIP practically even though the project contains the political concerns for many companies, government, and self-governing bodies. The four main technologies of the EIP developments include energy exchange, material flow analysis, water pinch, and life cycle assessment. Material flow analysis (MFA) methodology can be utilized in EIP modeling in view of the fact that the analysis of material flows and the optimized modeling are major purposes for the technological modeling of EIP. Through MFA methodology in POHANG EIP project, how to apply MFA modeling to EIP modeling and how to utilize software for MFA modeling are shown in this research.

• International Journal of Naval Architecture and Ocean Engineering
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• v.2 no.4
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• pp.177-184
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• 2010

In this study, geometric modeling techniques and their application to ship modeling and design are presented. Traditionally the hull shape is defined by using curves called the lines and various necessary computations are performed based on the discrete points obtained from the lines. However, some applications find difficulty in using the lines such as seakeeping analysis, which requires the computation of wetted part that is changing dynamically over time. To overcome such a problem and increase accuracy and efficiency in computation, two essential geometric modeling techniques, surface modeling and surface-to-surface intersection, are introduced and their application to ship modeling and analysis including hydrostatic computation, slamming and seakeeping analyses is presented.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.57 no.2
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• pp.96-101
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• 2008

The field of load modeling has attracted the attention since it plays an important role for improving the accuracy of stability analysis and power flow estimation. Also, load modeling is an essential factor in the simulation and evaluation of power system performance. However, conventional load modeling techniques have some limitations with respect to accuracy for nonlinear and composite loads. Thus, precision load modeling technique and reasonable application method is needed for more accurate power system analysis. In this paper, we develop an intelligent load modeling method based. on neural network and application techniques for power system. The proposed method makes it possible to effectively estimate the load model for nonlinear models as well as linear models. Reasonable application method is also proposed for stability analysis. To demonstrate the validity of the proposed method, various experiments are performed and their results are presented.

• Journal of Korean society of Dental Hygiene
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• v.22 no.6
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• pp.495-502
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• 2022

Objectives: The purpose of this study was to analyze research trends in dental hygiene using topic modeling and semantic network analysis. Methods: A total of 261 published studies were collected 686 key words from the Research Information Sharing Service (RISS) by 2019-2021. Topic modeling and semantic network analysis were performed using Textom. Results: The most frequently and frequency-inverse document frequently key words were 'dental hygienist', 'oral health', 'elderly', 'periodontal disease', 'dental hygiene'. N-gram of key words show that 'dental hygienist-emotional labor', 'dental hygienist-elderly', 'dental hygienist-job performance', 'oral health-quality of life', 'oral health-periodontal disease' etc. were frequently. Key words with high degree centrality were 'dental hygienist (0.317)', 'oral health (0.239)', 'elderly (0.127)', 'job satisfaction (0.057)', 'dental care (0.049)'. Extracted topics were 5 by topic modeling. Conclusions: Results from the current study could be available to know research trends in dental hygiene and it is necessary to improve more detailed and qualitative analysis in follow-up study.

• Journal of Digital Contents Society
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• v.19 no.5
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• pp.981-993
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• 2018

Smart healthcare is convergence of ICT and healthcare services, and interdisciplinary research has been actively conducted in various fields. The objective of this study is to investigate trends of smart healthcare research using topic modeling and ego network analysis. Text analysis, frequency analysis, topic modeling, word cloud, and ego network analysis were conducted for the abstracts of 2,690 articles in Scopus from 2001 to April 2018. Topic Modeling analysis resulted in eight topics, Topics included "AI in healthcare", "Smart hospital", "Healthcare platform", "Blockchain in healthcare", "Smart health data", "Mobile healthcare", " Wellness care", "Cognitive healthcare". In order to examine the topic modeling results core deeply, we analyzed word cloud and ego network analysis for eight topics. This study aims to identify trends in smart healthcare research and suggest implications for establishing future research direction.

• Journal of Information Technology Applications and Management
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• v.25 no.1
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• pp.33-45
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• 2018

This study was initiated to investigate the essential skill factors for system designers in order to build the right information systems. The predicted variables are mathematical modeling skill, verbal modeling skill, general IT knowledge, and general business knowledge. The test was administrated to 43 students majoring in Management Information Systems (MIS) at Hannam University, South Korea. In this study, we used Pearson Correlation Analysis to test the relationships among variables. Overall, our study suggested that there is a strong positive relationship between mathematical and verbal skills and IS modeling ability. A marginal positive relationship between the general IT knowledge and IS modeling ability was also found. Unexpectedly, there was no significant relationship between general business knowledge and IS modeling ability.

• Research in Mathematical Education
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• v.26 no.3
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• pp.253-270
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• 2023

This study aims to investigate the extent to which Korean high school textbooks incorporate opportunities for students to engage in the mathematical modeling process through tasks related to exponential and logarithmic functions. The tasks in three textbooks were analyzed based on the actions required for each stage in the mathematical modeling process, which includes identifying essential variables, formulating models, performing operations, interpreting results, and validating the outcomes. The study identified 324 units across the three textbooks, and the reliability coefficient was 0.869, indicating a high level of agreement in the coding process. The analysis revealed that the distribution of tasks requiring engagement in each of the five stages was similar in all three textbooks, reflecting the 2015 revised curriculum and national curriculum system. Among the 324 analyzed tasks, the highest proportion of the units required performing operations found in the mathematical modeling process. The findings suggest a need to include high-quality tasks that allow students to experience the entire process of mathematical modeling and to acknowledge the limitations of textbooks in providing appropriate opportunities for mathematical modeling with a heavy emphasis on performing operations. These results provide implications for the development of mathematical modeling activities and the reconstruction of textbook tasks in school mathematics, emphasizing the need to enhance opportunities for students to engage in mathematical modeling tasks and for teachers to provide support for students in the tasks.

• Spatial Information Research
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• v.10 no.4
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• pp.551-565
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• 2002

To carry out systematic groundwater assessment, exploration and management and to use these for protection of optimal groundwater yield, a data analysis and management system is required. Thus, the object of this research was to develop and apply software that integrates GIS and groundwater modeling: GISGAM (GIS for groundwater analysis and management system). The GIS program ArcView and the groundwater-modeling program MODFLOW were used for the GISGAM. The program components consist of a pre-processor, a processor, and a post-processor for groundwater modeling. In addition, GIS functions such as input, manipulation, analysis and output of data were embedded into the program. In applying the program to pilot area, topography, geology, soil, land use and well databases, and a groundwater flow model were constructed for the study area. This case study revealed the advantage and convenience of groundwater modeling using GIS capabilities. By integrating GIS and the groundwater model, the impact of changing values of hydrogeological constants on model results could be more easily evaluated.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.25 no.4
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• pp.61-68
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• 2002

This paper provides a method of consciousness structure analysis for research and development project evaluation using fuzzy structure modeling(FSM). Fuzzy structure modeling, which is a modeling method for consciousness structure, has a large number of pairwise comparison by human subjective judgement and is difficult to check the consistency index of denoting the precision for human judgement. Thus, in this paper, we analyzed the structure of consciousness by fuzzy structural modeling method, introducing the concept of pairwise comparison matrix in Analytic Hierarchy Process.