• Title/Summary/Keyword: Structured Model

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A Development of the Test of Earth Science Inquiry Abilities Using Structured Items (구조화된 문항을 이용한 지구과학 탐구능력 평가 도구 개발)

  • Cheong, Cheol;Woo, Jong-Ok;Kim, Jeong-Yul
    • Journal of The Korean Association For Science Education
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    • v.17 no.1
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    • pp.93-101
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    • 1997
  • The purpose of this study is to develop a test of earth science inquiry abilities using structured items. To develop a more valid and reliable instrument factual data was used, and most of the previous studies regarding inquiry teaching method and inquiry evaluation were consulted. The model developed in this study is composed of 5 stages; recognizing problems and generating hypotheses, designing inquiry, pursuiting inquiry, interpreting data, and drawing conclusion. Also, in this study 10 science inquiry abilities; recognizing problems, generating hypotheses, controlling variables, designing experiments, performing experiments, transforming data, inferencing, predicting, conclusing, and generalizing were clearly defined. The test developed in the study, Test of Earth Science Inquiry Abilities, includes 25 multiple-choice (five-choice) items and requires testing time of 50 minutes. The content validity of items, objectivity of scoring keys and clarity of items were checked by 7 experienced specialists in science education and earth science. The developed test were investigated and revised through three field tests. According to the results of the third field trial, test reliability (Cronbach $\alpha$) was 0.62, difficulty index was 0.54 and index of discrimination was 0.35. Also, the developed Test of Earth Science Inquiry Abilities showed a correlation coefficient of 0.53 with TIPS. Therefore, the development of Test of Earth Science Inquiry Abilities using structured items satisfied the reliability and validity requirements for general assessment instruments for students' earth science inquiry abilities.

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A Study on the Corona Discharge Simulation Using FEM-FCT Method (FEM-FCT 기법을 이용한 코로나 방전 시뮬레이션에 대한 연구)

  • Min, Ung-Gi;Kim, Hyeong-Seok;Lee, Seok-Hyeon;Han, Song-Yeop
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.48 no.3
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    • pp.200-208
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    • 1999
  • In this paper, the corona discharge is analyzed by Finite Element Method(FEM) combined with Flux-corrected Transport(FCT) algorithm. In the previous papers, Finite Difference Method(FDM) combined with FCT was used. Usually in the FDM, the regionof interest is discretized with structured grids. But to refine local regions with same resolution, much more grids are required for the structured grids than for unstructured grids than for unstructured grids. Therefore, we propose the FEM-FCT method to simulate the corona discharge. The proposed method has good flexibility in model shape and can reduce the computational cost by the local refinement where the physical quantities have steep gradients. Using the proposed method, we study the streamer growth of parallel plate electrodes which is initiated by the low and high perturbation density. We find that the varying the initial density of perturbation has very little effect on the streamer propagation. And the corona discharge of the rod-to-plane electrode is simulated. On the surface of the rod electrode, the high concentration of the electric field gives rise to many number of streamer seeds. The strong axial streamer propagate to the plane electrode. The weaker non-axial streamer repel each other and stop growing more. The results are very similar to those of the papers which used the FDM-FCT method on structured grids. Thus we can conclude that the proposed FEM-FCT method is more efficient than the conventional FDM-FCT method by virtue of the reduction in computational grids number.

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MPIL: Market prediction through image learning of unstructured and structured data (비정형, 정형 데이터의 이미지 학습을 활용한 시장예측)

  • Lee, Yoon Seon;Lee, Ju Hong;Choi, Bum Ghi;Song, Jae Won
    • Smart Media Journal
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    • v.10 no.2
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    • pp.16-21
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    • 2021
  • Financial time series analysis plays a very important role economically and socially in modern society and is an important task affecting global development, but due to difficulties such as a lot of noise and uncertainty, financial time series analysis prediction is a difficult research topic. In this paper, we propose a market prediction method (MPIL) by converting unstructured data and structured data into images. For market prediction, it analyzes SNS and news data, which is unstructured data for n days, and converts the market data, which is structured data, to an image with the GADF algorithm, and predicts an ultra-short market that predicts the price of n+1 days through image learning. MPIL has an average accuracy of 56%, which is higher than the 50% average accuracy of the model that predicts the market with LSTM by using sentiment analysis used for existing market forecasting.

Transformation from IDEF4 models to UML models (IDEF4 모델에서 UML 모델로의 변환)

  • Yoo, Moon-Sung
    • Journal of Korea Society of Industrial Information Systems
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    • v.16 no.5
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    • pp.83-92
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    • 2011
  • IDEF is a widely used methodology for traditional structured software development. As object-oriented softwares are widely used, an object-oriented version of IDEF, IDEF4, is developed. UML is de facto standard for object-oriented software development methods. Whereas IDEF is widely used for CALS/EC, UML is used for general object-oriented software development. Most software developers are not familiar with IDEF4 but familiar with UML. Moreover, UML has many CASE tools. So we can develop software efficiently if we convert IDEF4 model to UML model. In this paper, we transform IDEF4 models to UML models. We explain the rules and methods to convert IDEF4 model to UML model and applied the transform methods and rules to a case study.

A Prediction Model on the Male Nurses' Turnover Intention (남자 간호사의 이직의도 예측모형)

  • Kim, Su Ol;Kang, Younhee
    • Korean Journal of Adult Nursing
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    • v.28 no.5
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    • pp.585-594
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    • 2016
  • Purpose: The purpose of this study was to develop and test a predictive model on the male nurses' turnover intention. Methods: This study utilized the model-testing design based on the Price's causal model of turnover. This study collected data from 306 male nurses on a national scale with structured questionnaires measuring job opportunity, kinship responsibility, positive emotion, work autonomy, role conflict, work satisfaction, organizational commitment, and turnover intention. The data were analyzed using SPSS/WIN 22.0 program and AMOS 20.0 program. Results: As the outcomes satisfied the recommended level, the hypothetical model appeared to fit the data. Twenty-seven of the 38 hypotheses selected for the hypothetical model were statistically significant. 54.2% of turnover intention was explained by job opportunity, kinship responsibility, positive emotion, work autonomy, role conflict, work satisfaction and organizational commitment. Conclusion: The hypothetical model of this study was confirmed to be adequate in explaining and predicting male nurses' turnover intention. Findings from this study can be used to design appropriate strategies to decrease the male nurse's turnover intention.

A SCORM-based e-Learning Process Control Model and Its Modeling System

  • Kim, Hyun-Ah;Lee, Eun-Jung;Chun, Jun-Chul;Kim, Kwang-Hoon Pio
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.11
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    • pp.2121-2142
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    • 2011
  • In this paper, we propose an e-Learning process control model that aims to graphically describe and automatically generate the manifest of sequencing prerequisites in packaging SCORM's content aggregation models. In specifying the e-Learning activity sequencing, SCORM provides the concept of sequencing prerequisites to be manifested on each e-Learning activity of the corresponding tree-structured content organization model. However, the course developer is required to completely understand the SCORM's complicated sequencing prerequisites and other extensions. So, it is necessary to achieve an efficient way of packaging for the e-Learning content organization models. The e-Learning process control model proposed in this paper ought to be an impeccable solution for this problem. Consequently, this paper aims to realize a new concept of process-driven e-Learning content aggregating approach supporting the e-Learning process control model and to implement its e-Learning process modeling system graphically describing and automatically generating the SCORM's sequencing prerequisites. Eventually, the proposed model becomes a theoretical basis for implementing a SCORM-based e-Learning process management system satisfying the SCORM's sequencing prerequisite specifications. We strongly believe that the e-Learning process control model and its modeling system achieve convenient packaging in SCORM's content organization models and in implementing an e-Learning management system as well.

A Structural Equation Model on Mental Health of Korean Immigrants in Canada (캐나다 이민자의 정신건강 구조 모형)

  • Bae, Jeong-Yee;Park, Young-Suk
    • Journal of Korean Academy of Nursing
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    • v.40 no.3
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    • pp.389-399
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    • 2010
  • Purpose: The aim of this study was to construct a structural equation model that would further explain the mental health status of Korean immigrants living in Canada. Methods: Survey using a structured questionnaire was conducted with 386 people in Canada (Vancouver and Toronto). Six instruments were used in this model. The analysis of data was done with both SPSS 14.0 for descriptive statistics and AMOS 5.0 for covariance structure analysis. Results: Based on the constructed model, physical health status, immigrant life stress, self esteem, and quality of life were found to have significant direct effect on mental health. In addition, factors such as physical health status, immigrant life stress, quality of life, English proficiency, family cohesion and social support were found to indirectly affect mental health. The final modified model yielded Chi-square=34.79 (p<.001), df=13, $x^2$/df=2.68, GFI=0.98, AGFI=0.94, NFI=0.95, PNFI=0.44, PGFI=0.35, RMSE=0.07 and exhibited good fit indices. Conclusion: This structural equation model is a comprehensive theoretical model that explains the related factors and their relationship with mental health in Korean immigrants. Findings of this study can contribute to the designing of an appropriate prevention strategy to further improve the mental health of immigrants in Canada.

An XMDR-based Data Model for the Efficient Management of Ontology Schema (온톨로지 스키마의 효율적 관리를 위한 XMDR 기반의 데이터 모델 설계)

  • Lee, Junghun;Woo, Yongtae
    • Journal of Information Technology and Architecture
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    • v.10 no.2
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    • pp.263-271
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    • 2013
  • In this paper, we propose a new XMDR-based data model to efficiently manage ontology schema structured in OWL format. The proposed model would be better equipped to manage the relationship between concepts, which is a problematic area in the existing MDR model. Moreover, we present an algorithm to manage ontology schema in the database. To demonstrate the effectiveness of the proposed algorithm, experiments were conducted to recreate OWL documents for the various expressive types of OWL ontology schema that are stored in the database. These experimental results demonstrated that the proposed model effectively managed the various types of OWL ontology schema.

A Predictive Model on Turnover Intention of Nurses in Korea (간호사의 이직의도 예측모형)

  • Moon, Sook-Ja;Han, Sang-Sook
    • Journal of Korean Academy of Nursing
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    • v.41 no.5
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    • pp.633-641
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    • 2011
  • Purpose: The purpose of this study was to propose and test a predictive model that could explain and predict Korean nurses' turnover intentions. Methods: A survey using a structured questionnaire was conducted with 445 nurses in Korea. Six instruments were used in this model. The data were analyzed using SPSS 15.0 and Amos 7.0 program. Results: Based on the constructed model, organizational commitment, and burnout were found to have a significant direct effect on turnover intention of nurses. In addition, factors such as empowerment, job satisfaction, and organizational commitment were found to indirectly affect turnover intention of nurse. The final modified model yielded ${\chi}^2$=402.30, p<.001), ${\chi}^2$/df=2.94, RMSEA=0.07, RMR=0.03, GFI=0.90, AGF=0.87, NFI=0.88, CFI=0.92 and good fit indices. Conclusion: This structural equational model is a comprehensive theoretical model that explains the related factors and their relationship with turnover intention in Korean nurses. Findings from this study can be used to design appropriate strategies to further decrease the nurses' turnover intention in Korea.

Forecasting biomass and recruits by age-structured spawner-recruit model incorporating environmental variables (환경요인을 결합한 연령구조 재생산모델에 의한 자원량 및 가입량 예측)

  • Lee, Jae Bong;Lee, Dong Woo;Choi, Ilsu;Zhang, Chang Ik
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.48 no.4
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    • pp.445-451
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    • 2012
  • We developed an age-based spawner-recruit model incorporating environmental variables to forecast stock biomass and recruits of pelagic fish in this study. We applied the model to the Tsushima stock of jack mackerel, which is shared by Korea and Japan. The stock biomass of jack mackerel (Trachurus japonicus) around Korean waters ranged from 141 thousand metric tons (mt) and 728 thousand mt and recruits ranged from 27 thousand mt to 283 thousand mt. We hind-casted the stock biomass to evaluate the model performance and robustness for the period of 1987~2009. It was found that the model has been useful to forecast stock biomass and recruits for the period of the lifespan of fish species. The model is also capable of forecasting the long-term period, assuming a certain climatic regime.