• Title/Summary/Keyword: impact coefficient

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Retrieval of the Fraction of Photosynthetically Active Radiation (FPAR) using SPOT/VEGETATION over Korea (SPOT/VEGETATION 자료를 이용한 한반도의 광합성유효복사율(FPAR)의 산출)

  • Pi, Kyoung-Jin;Han, Kyung-Soo
    • Korean Journal of Remote Sensing
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    • v.26 no.5
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    • pp.537-547
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    • 2010
  • The importance of vegetation in studies of global climate and biogeochemical cycles is well recognized. Especially. the FPAR (fraction of photosynthetically active radiation) is one of the important parameters in ecosystem productivity and carbon budget models. Therefore, accurate estimates of vegetation parameters are increasingly important in environmental impact assessment studies. In this study, optical FPAR using the Terra MODIS (MODerate resolution Imaging Spectroradiometer), SPOT VEGETATION and ECOCLIMAP data reproduced on the Korean peninsula. We applied the empirical method which is usually estimated as a linear or nonlinear function of vegetation indices. As results, we estimated the accurate expression which is 0.9039 of $R^2$ in cropland and 0.7901 of $R^2$ in forest. Finally, this study could be demonstrated to calibrate that produced FPAR while the overall pattern and random noise through the comparative analysis of FPAR on the reference data. Optimal use of input parameter on the Korean peninsula should be helping the accuracy of output as well as the improved quality of research.

Calibration of APEX-Paddy Model using Experimental Field Data

  • Mohammad, Kamruzzaman;Hwang, Syewoon;Cho, Jaepil;Choi, Soon-Kun;Park, Chanwoo
    • Proceedings of the Korea Water Resources Association Conference
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    • 2019.05a
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    • pp.155-155
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    • 2019
  • The Agricultural Policy/Environmental eXtender (APEX) models have been developed for assessing agricultural management efforts and their effects on soil and water at the field scale as well as more complex multi-subarea landscapes, whole farms, and watersheds. National Academy of Agricultural Sciences, Wanju, Korea, has modified a key component of APEX application, named APEX-Paddy for simulating water quality with considering appropriate paddy management practices, such as puddling and flood irrigation management. Calibration and validation are an anticipated step before any model application. Simple techniques are essential to assess whether or not a parameter should be adjusted for calibration. However, very few study has been done to evaluate the ability of APEX-Paddy to simulate the impact of multiple management scenarios on nutrients loss. In this study, the observation data from experimental fields at Iksan in South Kora was used in calibration and evaluation process during 2013-2015. The APEX auto- calibration tool (APEX-CUTE) was used for model calibration and sensitivity analysis. Four quantitative statistics, the coefficient of determination ($R^2$),Nash-Sutcliffe(NSE),percentbias(PBIAS)androotmeansquareerror(RMSE)were used in model evaluation. In this study, the hydrological process of the modified model, APEX-Paddy, is being calibrated and tested in predicting runoff discharge rate and nutrient yield. Field-scale calibration and validation processes are described with an emphasis on essential calibration parameters and direction regarding logical sequences of calibration steps. This study helps to understand the calibration and validation way is further provided for applications of APEX-Paddy at the field scales.

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Impact of Spirituality on Clinical Practice among Dental Hygiene Students (치위생(학)과 재학생의 영성이 임상실습 스트레스에 미치는 영향)

  • Oh, Na-Rae;Kim, Hae-Kyoung
    • The Journal of the Korea Contents Association
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    • v.19 no.10
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    • pp.463-471
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    • 2019
  • This study examined the spirituality of dental hygiene and students and examined whether it affects the stress that may occur during clinical practice. The research tool consisted, clinical practice stresses, and general characteristics. It was held from March to July 2019 for 280 dental hygienists and students in K area. T-test and ANOVA were conducted for differences in spirituality and clinical practice stress according to general characteristics. The correlation between spirituality and clinical stress was analyzed by Pearson corrlation coefficients. As a result, dental hygiene and clinical practice stress of students were negatively correlated with spirituality, major satisfaction, and academic performance. If the motivation to apply to the department was grade, the clinical practice stress was higher. The limitation of this study is that it is impossible to make a concrete comparison because previous studies on the spirituality of dental hygiene and students are insufficient. Therefore, various studies on spirituality and clinical practice stress for dental hygienists are needed, and strategic search will be needed.

Classification of Wind Sector in Pohang Region Using Similarity of Time-Series Wind Vectors (시계열 풍속벡터의 유사성을 이용한 포항지역 바람권역 분류)

  • Kim, Hyun-Goo;Kim, Jinsol;Kang, Yong-Heack;Park, Hyeong-Dong
    • Journal of the Korean Solar Energy Society
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    • v.36 no.1
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    • pp.11-18
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    • 2016
  • The local wind systems in the Pohang region were categorized into wind sectors. Still, thorough knowledge of wind resource assessment, wind environment analysis, and atmospheric environmental impact assessment was required since the region has outstanding wind resources, it is located on the path of typhoon, and it has large-scale atmospheric pollution sources. To overcome the resolution limitation of meteorological dataset and problems of categorization criteria of the preceding studies, the high-resolution wind resource map of the Korea Institute of Energy Research was used as time-series meteorological data; the 2-step method of determining the clustering coefficient through hierarchical clustering analysis and subsequently categorizing the wind sectors through non-hierarchical K-means clustering analysis was adopted. The similarity of normalized time-series wind vector was proposed as the Euclidean distance. The meteor-statistical characteristics of the mean vector wind distribution and meteorological variables of each wind sector were compared. The comparison confirmed significant differences among wind sectors according to the terrain elevation, mean wind speed, Weibull shape parameter, etc.

Cross-cultural adaptation and validation of the Turkish Yellow Flag Questionnaire in patients with chronic musculoskeletal pain

  • Koc, Meltem;Bazancir, Zilan;Apaydin, Hakan;Talu, Burcu;Bayar, Kilichan
    • The Korean Journal of Pain
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    • v.34 no.4
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    • pp.501-508
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    • 2021
  • Background: Yellow flags are psychosocial factors shown to be indicative of long-term chronicity and disability. The purpose of the study was to evaluate the psychometric properties of the Turkish Yellow Flag Questionnaire (YFQ) in patients with chronic musculoskeletal pain (CMP). Methods: The cross-cultural adaptation was conducted with translation and back-translation of the original version. Reliability (internal consistency and test-retest) was examined for 231 patients with CMP. Construct validity was assessed by correlating the YFQ with the Hospital Anxiety and Depression Scale (HADS), Orebro Musculoskeletal Pain Questionnaire (OMPQ), and Tampa Kinesiophobia Scale (TKS). Factorial validity was examined with both exploratory and confirmatory factorial analysis. Results: The YFQ showed excellent test/retest reliability with an Intraclass correlation coefficient of 0.82. The internal consistency was moderate (Cronbach's alpha of 0.797). As a result of the exploratory factor analysis, there were 7 domains compatible with the original version. As a result of confirmatory factor analysis, the seven-factor structure of YFQ was confirmed. There was a statistically significant correlation between YFQ-total score and OMPQ (r = 0.57, P < 0.001), HADS-anxiety (r = 0.32, P < 0.001), HADS-depression (r = 0.44, P < 0.001), and TKS (r = 0.37, P < 0.001). Conclusions: This study's results provide considerable evidence that the Turkish version of the YFQ has appropriate psychometric properties, including test-retest reliability, internal consistency, construct validity and factorial validity. It can be used for evaluating psychosocial impact in patients with CMP.

On Larger Rate Volume of non-SIC NOMA over SIC NOMA for 3-user Correlated Information Sources (삼중 상관 정보원에서 SIC 대한 non-SIC 비직교 다중 접속의 확장 전송률 용적에 관해)

  • Chung, Kyu-Hyuk
    • The Journal of the Korea institute of electronic communication sciences
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    • v.16 no.3
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    • pp.457-464
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    • 2021
  • This paper investigates the achievable rate volumes for non-successive interference cancellation(SIC) non-orthogonal multiple access(NOMA) schemes, especially for 3-user correlated information sources(CIS). First, the closed-form expressions for the achievable rate volumes of non-SIC 3-user CIS NOMA are derived. Then it is numerically shown that the large correlation coefficients, as the achievable rate volumes of non-SIC 3-user CIS NOMA is larger than that of conventional SIC 3-user independent information sources(IIS) NOMA. We also demonstrate by various comparisons that the impact of the correlation coefficients of weaker channel gain users on achievable rate volume is more significant than those of stronger channel gain users.

Factors Affecting Logistics Capabilities for Logistics Service Providers: A Case Study in Vietnam

  • DANG, Dinh Dao;HA, Dieu Linh;TRAN, Van Bao;NGUYEN, Van Tuan;NGUYEN, Thi Lien Huong;DANG, Thuy Hong;LE, Thi Thai Ha
    • The Journal of Asian Finance, Economics and Business
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    • v.8 no.5
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    • pp.81-89
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    • 2021
  • This study aimed to investigate the factors affecting Logistics capabilities for Logistics Service Providers in Vietnam. Researchers inherited and developed based on previous research to focus on analyzing and evaluating dynamics, measuring Logistics capabilities, and the factors affecting Logistics capabilities for Logistics Service Providers. The logistics capabilities Model is used based on three factors: customer demand management capability, innovation capability, and information management capability. The empirical analysis used data from the survey data of l90 managers of Logistics Service Providers in Hai Phong, Ho Chi Minh City, Da Nang, Hue, Hanoi with reliable tools (SPSS 26.0 software). The data were analyzed by frequencies, percentages, means, Pearson's Linear Correlation Coefficient, exploratory factor analysis, and multi-linear regression model based on the survey data. The research results identified the following factors affecting Logistics capabilities for Logistics Service Providers: innovation capability has the strongest impact on Logistics capabilities; customer demand management capability has the following strong effects on Logistics capabilities; and finally, information management capability that affects Logistics capabilities. There is also a positive relationship between all factors and Logistics capabilities. Several recommendations are further suggested to enhance to improve Logistics capabilities for Logistics Service Providers in Vietnam.

Mediation Effects of Health Self-efficacy and Activity Confidence on the Relationship between Body Image and Health Promoting Behavior in Middle School Girls (여중생의 신체이미지와 건강증진행위와의 관계: 건강자기효능감과 활동역량의 매개효과를 중심으로)

  • Ryu, Jeong Lim;Back, Su-Mi
    • The Journal of Korean Society for School & Community Health Education
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    • v.22 no.4
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    • pp.11-24
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    • 2021
  • Purpose: This study aims to explore the mediating effect of the health self-efficacy and activity confidence in the relationship between body image and health promoting behavior in middle school girls. Methods: A descriptive correlational design was used. Participants were 142 in middle school girls. The questionnaire consisted of measuring tools for body image, health promoting behavior, health self-efficacy and activity confidence. The collected data were analyzed using descriptive statistics, independent t-test, one-way ANOVA, Pearson's correlation coefficient and the PROCESS Macro for SPSS 23.0 to verify the multiple mediated effect with a parallel structure. Results: Body image showed a significant positive correlation with health self-efficacy (r=.28, p=.001), activity confidence (r=.45, p<.001) and health promoting behavior (r=.37, p<.001). Health self-efficacy was also significantly correlated with activity confidence (r=.51, p<.001) and health promoting behavior (r=.63, p<.001). Activity confidence was significantly health promoting behavior (r=.67, p<.001). Furthermore, health self-efficacy (B=.35, p<.001) and activity confidence (B=.38, p<.001) showed a mediation effect on the relationship between body image and health promoting behavior. Conclusion: The impact of body image on health promoting behavior in middle school girls was mediated by health self-efficacy and activity confidence. Result suggest that strategies for improving health self-efficacy and activity confidence in middle school girls should be considered when developing an educational program for enhancing their health promoting behavior.

Cognitive Virtual Network Embedding Algorithm Based on Weighted Relative Entropy

  • Su, Yuze;Meng, Xiangru;Zhao, Zhiyuan;Li, Zhentao
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.4
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    • pp.1845-1865
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    • 2019
  • Current Internet is designed by lots of service providers with different objects and policies which make the direct deployment of radically new architecture and protocols on Internet nearly impossible without reaching a consensus among almost all of them. Network virtualization is proposed to fend off this ossification of Internet architecture and add diversity to the future Internet. As an important part of network virtualization, virtual network embedding (VNE) problem has received more and more attention. In order to solve the problems of large embedding cost, low acceptance ratio (AR) and environmental adaptability in VNE algorithms, cognitive method is introduced to improve the adaptability to the changing environment and a cognitive virtual network embedding algorithm based on weighted relative entropy (WRE-CVNE) is proposed in this paper. At first, the weighted relative entropy (WRE) method is proposed to select the suitable substrate nodes and paths in VNE. In WRE method, the ranking indicators and their weighting coefficients are selected to calculate the node importance and path importance. It is the basic of the WRE-CVNE. In virtual node embedding stage, the WRE method and breadth first search (BFS) algorithm are both used, and the node proximity is introduced into substrate node ranking to achieve the joint topology awareness. Finally, in virtual link embedding stage, the CPU resource balance degree, bandwidth resource balance degree and path hop counts are taken into account. The path importance is calculated based on the WRE method and the suitable substrate path is selected to reduce the resource fragmentation. Simulation results show that the proposed algorithm can significantly improve AR and the long-term average revenue to cost ratio (LTAR/CR) by adjusting the weighting coefficients in VNE stage according to the network environment. We also analyze the impact of weighting coefficient on the performance of the WRE-CVNE. In addition, the adaptability of the WRE-CVNE is researched in three different scenarios and the effectiveness and efficiency of the WRE-CVNE are demonstrated.

The Effects of NCS Education and Education Transition on Practical Results (국가직무능력표준 교육과 교육전이가 실무성과에 미치는 영향)

  • Choi, Soo Ho
    • Journal of Convergence for Information Technology
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    • v.9 no.3
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    • pp.82-89
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    • 2019
  • The reason why NCS education is conducted in college is because students are expected to improve their skills through practical education. In addition, NCS education is expected to have a positive impact on job competence and competitiveness. The purpose of this study is to explain the necessity of NCS education, and to analyze whether the education transition and practical performance are manifested. For this purpose, the research model was composed of "NCS Education ${\Rightarrow}$ Educational Transition ${\Rightarrow}$ Practical Results" and surveyed about 300 college students in the metropolitan area. If NCS education is necessary in practice, colleges and other educational institutions should plan to make NCS education operate efficiently. As a analysis result, it was confirmed that the internal consistency was secured and both the intensive validity & discriminant validity were confirmed in the validity. As a result of using the structural equation model, this research model was found to be suitable. As a result of the hypothesis test, it is analyzed that the standardization coefficient of the research hypothesis is above the appropriate level and the correlation is highly formed.