• Title/Summary/Keyword: Correlation model

Search Result 6,736, Processing Time 0.038 seconds

A Novel Data Prediction Model using Data Weights and Neural Network based on R for Meaning Analysis between Data (데이터간 의미 분석을 위한 R기반의 데이터 가중치 및 신경망기반의 데이터 예측 모형에 관한 연구)

  • Jung, Se Hoon;Kim, Jong Chan;Sim, Chun Bo
    • Journal of Korea Multimedia Society
    • /
    • v.18 no.4
    • /
    • pp.524-532
    • /
    • 2015
  • All data created in BigData times is included potentially meaning and correlation in data. A variety of data during a day in all society sectors has become created and stored. Research areas in analysis and grasp meaning between data is proceeding briskly. Especially, accuracy of meaning prediction and data imbalance problem between data for analysis is part in course of something important in data analysis field. In this paper, we proposed data prediction model based on data weights and neural network using R for meaning analysis between data. Proposed data prediction model is composed of classification model and analysis model. Classification model is working as weights application of normal distribution and optimum independent variable selection of multiple regression analysis. Analysis model role is increased prediction accuracy of output variable through neural network. Performance evaluation result, we were confirmed superiority of prediction model so that performance of result prediction through primitive data was measured 87.475% by proposed data prediction model.

Development and Validation of the Coupled System of Unified Model (UM) and PArameterized FOG (PAFOG) (기상청 현업 모형(UM)과 1차원 난류모형(PAFOG)의 접합시스템 개발 및 검증)

  • Kim, Wonheung;Yum, Seong Soo
    • Atmosphere
    • /
    • v.25 no.1
    • /
    • pp.149-154
    • /
    • 2015
  • As an attempt to improve fog predictability at Incheon International Airport (IIA) we couple the 3D weather forecasting model currently operational in Korea Meteorological Administration (regional Unified Model, UM_RE) with a 1D turbulence model (PAFOG). The coupling is done by extracting the meteorological data from the 3D model and properly inserting them in the PAFOG model as initial conditions and external forcing. The initial conditions include surface temperature, 2 m temperature and dew point temperature, geostrophic wind at 850 hPa and vertical profiles of temperature and dew point temperature. Moisture and temperature advections are included as external forcing and updated every hr. To validate the performance of the coupled system, simulation results of the coupled system are compared to those of the 3D model alone for the 22 sea fog cases observed over the Yellow Sea. Three statistical indices, i.e., Root Mean Square Error (RMSE), linear correlation coefficient (R) and Critical Success Index (CSI), are examined, and they all indicate that the coupled system performs better than the 3D model alone. These are certainly promising results but more improvement is required before the coupled system can actually be used as an operational fog forecasting model. For the RMSE, R, and CSI values for the coupled system are still not good enough for operational fog forecast.

USING TRMM SATELLITE C BAND DATA TO RETRIEVE SOIL MOISTURE ON THE TffiETAN PLATEAU

  • Chang Tzu-Yin;Liou Yuei-An
    • Proceedings of the KSRS Conference
    • /
    • 2005.10a
    • /
    • pp.737-740
    • /
    • 2005
  • Soil moisture, through its dominance in the exchange of energy and moisture between the land and atmosphere, plays a crucial role in influencing atmospheric circulation. To identify the crucial role, it is a common agreement that knowledge of land surface processes and development of remote sensing techniques are of great important scientific issues. This research uses TRMM satellite C band (10.65 GHz) data to retrieve soil moisture on the Tibetan Plateau in Mainland China. Two retrieval schemes that are implemented include the t-(J) model and the R model. The latter one is developed based on a land surface process and radiobrightness (R) model for bare soil and vegetated terrain. Compared with the in situ ground measurements, the soil moisture retrieved from the R model and the t-(J) model with vegetation information obviously appear more accurate than that derived from bare soil model. Retrieved soil moisture contents from the two inversion models, R model and t-(J) model, have a similar trend, but the former appears to be superior in terms of correlation coefficient and bias compared with in situ data. In the future, we will apply the R model with the TRMM 10.65 GHz brightness temperature to monitor long-term soil moisture variation over Tibet Plateau.

  • PDF

Performance Analysis of the NREL Phase IV Wind Turbine by CFD (CFD에 의한 NREL Phase IV 풍력터빈 성능해석)

  • Kim, Bum-Suk;Kim, Mann-Eung;Lee, Young-Ho
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2008.03b
    • /
    • pp.652-655
    • /
    • 2008
  • Despite of the laminar-turbulent transition region co-exist with fully turbulence region around the leading edge of an airfoil, still lots of researchers apply to fully turbulence models to predict aerodynamic characteristics. It is well known that fully turbulent model such as standard k-${\varepsilon}$ model couldn't predict the complex stall and the separation behavior on an airfoil accurately, it usually leads to over prediction of the aerodynamic characteristics such as lift and drag forces. So, we apply correlation based transition model to predict aerodynamic performance of the NREL (National Renewable Energy Laboratory) Phase IV wind turbine. And also, compare the computed results from transition model with experimental measurement and fully turbulence results. Results are presented for a range of wind speed, for a NREL Phase IV wind turbine rotor. Low speed shaft torque, power, root bending moment, aerodynamic coefficients of 2D airfoil and several flow field figures results included in this study. As a result, the low speed shaft torque predicted by transitional turbulence model is very good agree with the experimental measurement in whole operating conditions but fully turbulent model(k-${\varepsilon}$) over predict the shaft torque after 7m/s. Root bending moment is also good agreement between the prediction and experiments for most of the operating conditions, especially with the transition model.

  • PDF

Musculoskeletal model during isokinetic knee motion;Simulation and Experiment (슬관절 등속 운동시 하지근육구동모델;모의실험과 임상실험)

  • Bae, Tae-Soo;Cho, Hyeon-Seok;Kang, Sung-Jae;Choi, Kyong-Joo;Kim, Shin-Ki;Mun, Mu-Seong
    • Proceedings of the KSME Conference
    • /
    • 2003.11a
    • /
    • pp.1554-1559
    • /
    • 2003
  • This study validated the musculoskeletal model of the human lower extremity by comparative study between calculated muscle parameters through simulation using modified hill-type model and measured them through isokinetic exercise. And the relationship between muscle forces and moments participated in motion was quantified from the results of simulation. For simulation of isokinetic motion, a three-dimensional anatomical knee model was constructed using trials of gait analysis and the EMG-force model was used to determine muscle activation level exciting muscles. The modified Hill-type model was used to calculate individual muscle forces and moments in dynmaic analysis and the results were validated by comparing them of experiments on BIODEX. The results showed that there was a high correlation between calculated torques from simulation and measured them from experiments for isokinetic motion(R=0.97). Therefore we concluded that the simulation by using musculoskeletal model was so useful means to predict and convalesce musculoskeletal-related diseases, and analyze unrealizable experiment such as clash condition.

  • PDF

Factors Influencing Health Promoting Behavior of Women College Students (여대생의 건강증진행위에 영향을 미치는 요인)

  • Kim, Joo-Hyun;Kim, Sung-Jae;Park, Yeon-Hwan
    • Korean Journal of Adult Nursing
    • /
    • v.13 no.3
    • /
    • pp.431-440
    • /
    • 2001
  • The purpose of this study was to identify the factors influencing health promoting behavior of college students to develop health promoting interventions of young adults. The subjects of this study were 176 women college students, living in a small city in Korea. The data were collected by interviews and a self-report questionnaire, during the period from September, 1999 to December, 1999. The instruments for this study were the PRQ-II by Weinert(1988), the scale of Locus of Control by Wallstone et al.(1978), the scale of self efficacy by Sherer & Maddux(1982), 10 points visual analogue scale for perceived health status and the importance of health, the health promoting behavior scale by Walker et al.(1987), and the scales developed by the authors for the perceived benefits of health promoting behavior, and perceived barriers to health promoting behavior. Cronbach 's alpha of these scales were .68 ~.89. The data were analyzed using descriptive statistics, Pearson's correlation coefficients, and stepwise multiple regression. The results of this study were as follows: 1. Among cognitive perceptual factors of the Health Promotion Model by Pender(1987), the scores of the importance of health, the perceived internal control of health, self efficacy, the perceived health status, and the perceived benefits had a significantly positive correlation with the scores of the health promoting behavior of college students. In addition, the scores of the perceived barriers had a significantly negative correlation with the scores of the health promoting behavior of college students. 2. Among modifying factors of the Health Promotion Model by Pender(1987), the extent of religious activities of college students and the scores of social support had a significantly positive correlation with the scores of health promoting behavior of college students. 3. Stepwise multiple regression analysis revealed that the most powerful predictor of health promoting behavior was self-efficacy. A combination of self-efficacy, the perceived benefits, the perceived barriers, the perceived health status, and the importance of health accounted for 45.1% of the variance in health promoting behavior in college students From the results of this study, we concluded that the Health Promotion Model by Pender can be used to explain health promoting behavior of college students. In addition, we suggested that the results of this study be considered in developing health promoting programs of young adults.

  • PDF

The Effects of Urban Forest on Summer Air Temperature in Seoul, Korea (도시림의 여름 대기온도 저감효과 - 서울시를 대상으로 -)

  • 조용현;신수영
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.30 no.4
    • /
    • pp.28-36
    • /
    • 2002
  • The main purpose of this study was to estimate a new regression model to explain the relationship between urban forest and air temperature in summer, 2001. This study consists of two parts: correlation coefficient analysis and regression analysis. According to correlation coefficient analysis, thermal infra-red radiations of the major land use categories found significant difference in each category. However there were no significant relationship between the data (thermal infra-red radiation and NDVI) derived from Landsat-7 ETM+ image and air temperature at Automatic Weather Stations(AWSs). After estimating various regression models for summer air temperature, the final models were chosen. The final regression models consisted of two variables such as forest m and traffic facilities area. The regression models explained over 78% of the variability in air temperatures. The regression models with variables of forest area and traffic facilities area showed that the coefficient of the first variable was even more significant than the second one. However, the negative impact of the traffic facilities area was slightly greater than the positive impact of the forest area. Consequently, the effects of forest area and traffic facilities area were apparent to explain summer air temperature in Seoul. Therefore two policies have the most important implications to mitigate the summer air temperature in Seoul: to expand and to conserve the urban forest; and to change the Oafnc facilities'characteristics. The results from this study are expected to be useful not merely in informing the public that urban forest mitigates summer air temperahne, but in urging the necessity of budgets for trees and managing urban forests. It is recommended that field swey of summer air temperature be Performed for the vadidation of the models. The main purpose of this study was to estimate a new regression model to explain the relationship between urban forest and air temperature in summer, 2001. This study consists of two parts: correlation coefficient analysis and regression analysis. According to correlation coefficient analysis, thermal infra-red radiations of the major land use categories found significant difference in each category. However there were no significant relationship between the data (thermal infra-red radiation and NDVI) derived from Landsat-7 ETM+ image and air temperature at Automatic Weather Stations(AWSs). After estimating various regression models for summer air temperature, the final models were chosen. The final regression models consisted of two variables such as forest m and traffic facilities area. The regression models explained over 78% of the variability in air temperatures. The regression models with variables of forest area and traffic facilities area showed that the coefficient of the first variable was even more significant than the second one. However, the negative impact of the traffic facilities area was slightly greater than the positive impact of the forest area. Consequently, the effects of forest area and traffic facilities area were apparent to explain summer air temperature in Seoul. Therefore two policies have the most important implications to mitigate the summer air temperature in Seoul: to expand and to conserve the urban forest; and to change the traffic facilities'characteristics. The results from this study are expected to be useful not merely in informing the public that urban forest mitigates summer air temperature, but in urging the necessity of budgets for trees and managing urban forests. It is recommended that field survey of summer air temperature be Performed for the vadidation of the models.

A New Software for Quantitative Measurement of Strabismus based on Digital Image (디지털 영상 기반 정량적인 사시각 측정을 위한 새로운 소프트웨어)

  • Kim, Tae-Yun;Seo, Sang-Sin;Kim, Young-Jae;Yang, Hee-Kyung;Hwang, Jeong-Min;Kim, Kwang-Gi
    • Journal of Korea Multimedia Society
    • /
    • v.15 no.5
    • /
    • pp.595-605
    • /
    • 2012
  • Various methods for measuring strabismus have been developed and used in clinical diagnosis. However, most of them are based on the visual inspection by clinicians. For this reason, there is a high possibility of subjective evaluation in clinical decisions and they are only useful for cooperative patients. Therefore, the development of a more objective and reproducible method for measuring strabismus is needed. In this paper, we introduce a new software to complement the limitations of previous diagnostic methods. Firstly, we simply obtained facial images of patients and performed several preprocessing steps based on the spherical RGB color model with them. Then, the measurement of strabismus was performed automatically by using our 3D eye model and mathematical algorithm. To evaluate the validity of our software, we performed statistical correlation analysis of the results of the proposed method and the Krimsky test by two clinicians for ten patients. The coefficients of correlation for two clinicians were very high, 0.955 and 0.969, respectively. The coefficient of correlation between two clinicians also showed 0.968. We found a statistically significant correlation between two methods from our results. The newly developed software showed a possibility that it can be used as an alternative or effective assistant tool of previous diagnostic methods for strabismus.

A Study on the Characteristics of Natural Frequency and Impedance of Elastically Restrained Cracked Beam with a Tip Mass (말단질량을 갖는 탄성지지 균열보의 고유주파수와 임피던스 특성 연구)

  • Lee, Jong-Won
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.21 no.11
    • /
    • pp.317-325
    • /
    • 2020
  • The development of a technique that can monitor the cracks, which is one of the typical types of damage, is necessary to secure the structural safety of elastically restrained cantilever-type beams with a tip mass that is used widely in infrastructure. Impedance techniques have been actively researched to detect cracks, and the cracks were estimated mainly by experimentally investigating the relationship between the crack and impedance signal. This study examined the correlation between the change in the impedance signals due to the crack, and the natural frequency obtained analytically. After updating the analysis model for the intact beam, the impedance signal was measured while gradually inflicting cracks in the cantilever-type beam, and the damage index was obtained. The results were compared with the natural frequencies calculated from the updated analysis model to investigate the correlation. A close correlation was observed between the experimentally obtained impedance damage index, and the analytically calculated natural frequency. Using this correlation, the structural characteristics could be evaluated more accurately from the damage estimation results, and the behavior of the structure could be predicted effectively using the analysis model.

Health Behavior of the Obese Adult - Based on the Johnson's Behavioral System Model (비만성인의 건강관련 행위 -Johnson의 행위체계 모형 적용-)

  • Kim, Jeong-Hee;Yun, Soon-Nyoung
    • Research in Community and Public Health Nursing
    • /
    • v.8 no.2
    • /
    • pp.277-288
    • /
    • 1997
  • The purpose of this study is to identify the behavioral subsystems of the obese adult and contribute to the utility of Johnson's Behavioral System Model. The subjects were 167 obese adults in out-patients clinics of 2 hospitals and health clinics for 4 companies. These data were collected by a structured questionnaire with 52 items from July 1 to Sep. 30, 1995. The instrument used for this study was modified from the DBSM -self reporting instrument (1983) and Grubbs(1980)'s. The reliability of this method was cronbach's ${\alpha}$=.8476 and the construct validity of it was accepted by using a factor analysis. These data were analyzed by frequency, percentage, mean, standard deviation, factor analysis, pearson's correlation coefficient, Kruskal-Wallis with an SPSS PC+ Program. The results of this study were as follows: 1. The 9 behavioral subsystems of the obese were indentified : sex-related, attachment-affiliative I(social), dependency, ingestive, eliminative, restorative, aggressive-protective, attachment-affiliative and II (familial), an achievement behavioral subsystem. 2. Out of 9 subsystems, the highest significant positive correlation between dependency and acheivement subsystem was found(r=.5357, p<.01), The next, attachment-affiliative I and attachment-affiliative II subsystem was correlated significantly (r=.4526, p<.01). Significant positive correlations among sex-related, achivement, attachment-affiliative I, II, dependency, restorative, and aggressive-protective subsystems were found. But, ingestive and eliminative subsystems were not correlated with the above seven subsystems significantly, only the positive correlation between the ingestive and eliminative subsystems was found. 3. The explained variance of the 9 subsystems was explained as 56.1% out of a total of one. The sex-related subsystem was the first factor explaining 16.3% of the total variance and then the next 8 factors which resulted in 39.8%. According to the results of this study, the suggestions were as follows: 1. In the nursing practice, nursing assessmentand intervention of the obese should be in cluded not only in ingestive and eliminative subsystems but also in sex-related, attachment-affiliative I, dependency, restorative, aggressive-protective, attachment -affiliative II, and achievement behavioral subsystem. 2. Concerning instruments, some items to measure the eliminative, dependency, and aggressive-protective behavioral subsystems with relatively reliability are needed. 3. Johnson's concept of a dependency subsystem should be clarified. 4. Correlation among the 7 subsystems, and the ingestive and eliminative subsystems should be clarified.

  • PDF