• Title/Summary/Keyword: 비선형 자기회귀

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Exploring NDVI Gradient Varying Across Landform and Solar Intensity using GWR: a Case Study of Mt. Geumgang in North Korea (GWR을 활용한 NDVI와 지형·태양광도의 상관성 평가 : 금강산 지역을 사례로)

  • Kim, Jun Woo;Um, Jung Sup
    • Journal of Korean Society for Geospatial Information Science
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    • v.21 no.4
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    • pp.73-81
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    • 2013
  • Ordinary least squares (OLS) regression is the primary statistical method in previous studies for vegetation distribution patterns in relation to landform. However, this global regression lacks the ability to uncover some local-specific relationships and spatial autocorrelation in model residuals. This study employed geographically weighted regression (GWR) to examine the spatially varying relationships between NDVI (Normalized Difference Vegetation Index) patterns and changing trends of landform (elevation, slope) and solar intensity (insolation and duration of sunshine) in Mt Geum-gang of North-Korea. Results denoted that GWR was more powerful than OLS in interpreting relationships between NDVI patterns and landform/solar intensity, since GWR was characterized by higher adjusted R2, and reduced spatial autocorrelations in model residuals. Unlike OLS regression, GWR allowed the coefficients of explanatory variables to differ by locality by giving relatively more weight to NDVI patterns which are affected by local landform and solar factors. The strength of the regression relationships in the GWR increased significantly, by showing regression coefficient of higher than 70% (0.744) in the southern ridge of the experimental area. It is anticipated that this research output will serve to increase the scientific and objective vegetation monitoring in relation to landform and solar intensity by overcoming serious constraints suffered from the past non-GWR-based approach.

Who Gets Government SME R&D Subsidy? Application of Gradient Boosting Model (Gradient Boosting 모형을 이용한 중소기업 R&D 지원금 결정요인 분석)

  • Kang, Sung Won;Kang, HeeChan
    • The Journal of Society for e-Business Studies
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    • v.25 no.4
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    • pp.77-109
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    • 2020
  • In this paper, we build a gradient Boosting model to predict government SME R&D subsidy, select features of high importance, and measure the impact of each features to the predicted subsidy using PDP and SHAP value. Unlike previous empirical researches, we focus on the effect of the R&D subsidy distribution pattern to the incentive of the firms participating subsidy competition. We used the firm data constructed by KISTEP linking government R&D subsidy record with financial statements provided by NICE, and applied a Gradient Boosting model to predict R&D subsidy. We found that firms with higher R&D performance and larger R&D investment tend to have higher R&D subsidies, but firms with higher operation profit or total asset turnover rate tend to have lower R&D subsidies. Our results suggest that current government R&D subsidy distribution pattern provides incentive to improve R&D project performance, but not business performance.

The Effect of Adaptation Education on Performance Confidence and Practical Skill of Dental Hygiene Students before Field Practice (현장실습 전 현장적응교육이 치위생과 재학생의 수행자신감과 실무능력에 미치는 효과)

  • Kim, Myung-Eun;Kim, Hee-Kyoung
    • The Journal of the Korea Contents Association
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    • v.22 no.1
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    • pp.620-628
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    • 2022
  • The purpose of this study is to confirm the degree of improvement in performance confidence and executive ability after conducting field adaptation education to dental hygiene students who start their first field practice. Thirty dental hygiene students were evaluated with performance confidence, indirect and direct evaluation of practical skill before and after the field adaptation education was conducted for 15 hours. Also field practice satisfaction was investigated after field practice. A paired t-test was conducted to compare performance confidence, indirect executive ability, and direct practical ability before and after education. Pearson's correlation was performed on the correlation between field adaptation education and field practice satisfaction. Linear regression analysis was performed to identify the influencing factors of field practice satisfaction. As a results, performance confidence, indirect and direct practical skills of after field adaptation program were increased than before that(p<0.05). The correlation between field adaptation education and field practice satisfaction showed that "education satisfaction" among the field adaptation education sub-regions correlated with "education content" and "support of field practice" among the field practice satisfaction sub-regions(p<0.05). Therefore, it is necessary to develop and management various adaptation education in the future as it increases the adaptability of the first field practice and increases the satisfaction of field practice.