• Title/Summary/Keyword: Factor Regression Model

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Assessment of the Contribution of Weather, Vegetation and Land Use Change for Agricultural Reservoir and Stream Watershed using the SLURP model (II) - Calibration, Validation and Application of the Model - (SLURP 모형을 이용한 기후, 식생, 토지이용변화가 농업용 저수지 유역과 하천유역에 미치는 기여도 평가(II) - 모형의 검·보정 및 적용 -)

  • Park, Geun-Ae;Ahn, So-Ra;Park, Min-Ji;Kim, Seong-Joon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.2B
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    • pp.121-135
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    • 2010
  • This study is to assess the effect of potential future climate change on the inflow of agricultural reservoir and its impact to downstream streamflow by reservoir operation for paddy irrigation water supply using the SLURP. Before the future analysis, the SLURP model was calibrated using the 6 years daily streamflow records (1998-200398 and validated using 3 years streamflow data (2004-200698 for a 366.5 $km^2$ watershed including two agricultural reservoirs (Geumgwang8 and Gosam98located in Anseongcheon watershed. The calibration and validation results showed that the model was able to simulate the daily streamflow well considering the reservoir operation for paddy irrigation and flood discharge, with a coefficient of determination and Nash-Sutcliffe efficiency ranging from s 7 to s 9 and 0.5 to s 8 respectively. Then, the future potential climate change impact was assessed using the future wthe fu data was downscaled by nge impFactor method throuih bias-correction, the future land uses wtre predicted by modified CA-Markov technique, and the future ve potentiacovfu information was predicted and considered by the linear regression bpowten mecthly NDVI from NOAA AVHRR ima ps and mecthly mean temperature. The future (2020s, 2050s and 2e 0s) reservoir inflow, the temporal changes of reservoir storaimpand its impact to downstream streamflow watershed wtre analyzed for the A2 and B2 climate change scenarios based on a base year (2005). At an annual temporal scale, the reservoir inflow and storaimpchange oue, anagricultural reservoir wtre projected to big decrease innautumnnunder all possiblmpcombinations of conditions. The future streamflow, soossmoosture and grounwater recharge decreased slightly, whtre as the evapotransporation was projected to increase largely for all possiblmpcombinations of the conditions. At last, this study was analysed contribution of weather, vegetation and land use change to assess which factor biggest impact on agricultural reservoir and stream watershed. As a result, weather change biggest impact on agricultural reservoir inflow, storage, streamflow, evapotranspiration, soil moisture and groundwater recharge.

The Effect of Social Network on Information Sharing in Franchise System (프랜차이즈시스템의 사회연결망 특성이 정보공유에 미치는 영향)

  • Yun, Han-Sung;Bae, Sang-Wook;Noh, Jung-Koo
    • Journal of Distribution Research
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    • v.16 no.2
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    • pp.95-118
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    • 2011
  • The purpose of this study is as follows. First, we investigate empirically the effects of social network properties such as social network density and centrality of a franchisee on its information sharing with various subjects such as the franchisor and other franchisees in the franchise system. Second, we examine exploratively if tie strength between a franchisee and its franchisor plays a moderating role on the relationship between social network properties and information sharing. The study model was established as shown in

    . We gathered 200 data from franchisees in Busan through a questionnaire survey and used 189 data for our purpose. To improve the quality of data, we selected respondents from the franchisees' owners or managers that had contacted often with their franchisor and other franchisees in the franchise system. Our data analysis began with reliability analysis, exploratory and confirmatory factor analysis, on the multi-item measures of social network density, social network centrality, tie strength, information sharing and control variables such as shared goals and ownership to assess the reliability and validity of those measures. The results were shown that the presented values satisfied the general criteria for reliability and validity. We tested our hypotheses using a hierarchical multiple regression analysis in four steps. Model 1 regressed the dependent variable(information sharing) only on control variables(shared goals, ownership). Model 2 added main effect variables(social network density, social network centrality) in Model 1. Model 3 added a moderating variable(tie strength) in Model 2. Finally, Model 4 added interaction terms between the main variables and the moderating variable in Model 3. We used a mean-centering method for the main variables and the moderating variable to minimize the multicollinearity problem due to the interaction terms in Model 4. Two important empirical findings emerge from this study. In other words, the effects of social network properties and tie strength on a franchisee's information sharing depend on subject types such as the franchisor and other franchisees in franchise system. First, social network centrality, tie strength, the interaction between social network density and tie strength and the interaction between social network centrality and tie strength all affect significantly a franchisee's information sharing with its franchisor. By the way, the interaction between social network centrality and tie strength has a negative effect on its information sharing while the interaction of social network density and tie strength has a positive effect on its information sharing. Second, both social network centrality affects significantly and directly a franchisee's information sharing with other franchisees in the franchise system. However, there does not exist the moderating role of tie strength in the second case. Finally, we suggest the implications of our findings and some avenues for future research.

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Level of Service of Signalized Intersections Considering both Delay and Accidents (지체와 사고를 고려한 신호교차로 서비스수준 산정에 관한 연구)

  • Park, Je-Jin;Park, Seong-Yong;Ha, Tae-Jun
    • Journal of Korean Society of Transportation
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    • v.26 no.3
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    • pp.169-178
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    • 2008
  • Level of Service (LOS) is one of ways to evaluate operational conditions. It is very important factor in evaluation especially for the facility of highways. However, some studies proved that ${\upsilon}/c$ ratio and accident rate is appeared like a second function which has a U-form. It means there is a gap between LOS and safety of highway facilities. Therefore, this study presents a method for evaluation of a signalized intersection which is considered both smooth traffic operation (delay) and traffic safety (accident). Firstly, as a result of our research, accident rates and EPDO are decreased when it has a big delay. In that reason, it is necessary to make a new Level of Service included traffic safety. Secondly, this study has developed a negative binominal regression model which is based on the relation between accident patterns and stream. Thirdly, standards of LOS are presented which is originated from calculation between annual delay costs and annual accident cost at each intersection. Lastly, worksheet form is presented as an expression to an estimation step of a signalized intersection with traffic accident prediction model and new LOS.

Influence of the CYP1A1 T3801C Polymorphism on Tobacco and Alcohol-Associated Head and Neck Cancer Susceptibility in Northeast India

  • Singh, Seram Anil;Choudhury, Javed Hussain;Kapfo, Wetetsho;Kundu, Sharbadeb;Dhar, Bishal;Laskar, Shaheen;Das, Raima;Kumar, Manish;Ghosh, Sankar Kumar
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.16
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    • pp.6953-6961
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    • 2015
  • Background: Tobacco and alcohol contain or may generate carcinogenic compounds related to cancers. CYP1A1 enzymes act upon these carcinogens before elimination from the body. The aim of this study was to investigate whether CYP1A1 T3801C polymorphism modulates the relationship between tobacco and alcohol-associated head and neck cancer (HNC) susceptibility among the northeast Indian population. Materials and Methods: One hundred and seventy histologically confirmed HNC cases and 230 controls were included within the study. The CYP1A1 T3801C polymorphism was determined using PCR-RFLP, and the results were confirmed by DNA sequencing. Logistic regression (LR) and multifactor dimensionality reduction (MDR) approaches were applied for statistical analysis. Results: The CYP1A1 CC genotype was significantly associated with HNC risk (P=0.045). A significantly increased risk of HNC (OR=6.09; P<0.0001) was observed in individuals with combined habits of smoking, alcohol drinking and tobacco-betel quid chewing. Further, gene-environment interactions revealed enhanced risks of HNC among smokers, alcohol drinkers and tobacco-betel quid chewers carrying CYP1A1 TC or CC genotypes. The highest risk of HNC was observed among smokers (OR=7.55; P=0.009) and chewers (OR=10.8; P<0.0001) carrying the CYP1A1 CC genotype. In MDR analysis, the best model for HNC risk was the three-factor model combination of smoking, tobacco-betel quid chewing and the CYP1A1 variant genotype (CVC=99/100; TBA=0.605; P<0.0001); whereas interaction entropy graphs showed synergistic interaction between tobacco habits and CYP1A1. Conclusions: Our results confirm that the CYP1A1 T3801C polymorphism modifies the risk of HNC and further demonstrated importance of gene-environment interaction.

A Study on Hypertensive Patients Compliance to Medical Recommendations (고혈압 환자의 치료지시 이행에 관한 연구)

  • 최영희
    • Journal of Korean Academy of Nursing
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    • v.10 no.2
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    • pp.73-85
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    • 1980
  • The purpose of this study was to investigate the compliance behavior of hypertensive patients in light of their health belief model that explains an individual's compliance with health maintenance or getting well. Although there are many effective regimens and treatments for hypertension nowadays. the most important point to be taken to consideration in their behavioral aspect is their compliance with regard to the control of body weight. eating habits as to salt and cholesterol intake. stresses. activity patterns and smoking as related to their life style. The important reasons for the failure in the control of hypertensive patients are the complexity of regimens to be complied to. irregular medication and the life long restrictions in their own life style. The compliance of patients to medical regimens and rocommendations or failure to do so is an essential factor. Accordingly. the degree of the patient's compliance is an important determinant as to the success or failure of hypertension control. The subjects for this study were 187 hypertensive patients selected from admitted and out patients of the medical department at seven University Hospitals in Seoul. Data was collected from Dec. 1, 1979 to Feb. 15, 1980 using the questionaire method and was analysed by the use of means. standard deviations, coefficient of correlations, analysis of variance and multiple regression analysis. The results obtained are as follows A. Of the seven independent variables in light of health belief model. benefit. barrier and severity are closely related to patient's compliance behavior. Therefore these variables could be used as determinants to predict and modify the hypertensive behavior. 1. Benefit is the most important and significant of the variables for explaining the dependent variables. It accounts for the highest variance of patient's compliance. (23.62%) 2. Then taking the former together with barrier. the variance of compliance showed on increase. (26.59%) 3. And with the addition of severity to the first two. the variance of compliance was also increased. (28.l2 %) B. Except for susceptibility all the independent variables such as severity. benefit, knowledge. motivation and barrier are correlated to dependent variable compliance. C. Sex. marital status and religion appeared to have significant influence on the dependent variables. Therefore one could conclude that the more the patients are aware that hypertension is a threat to health. the more they understand the benefit of taking actions to prevent such a threat. and the less they perceive any barrier when taking action. the more compliant they become in following medical regimens and recommendations. Age. marital status and religion played a significant influence to their compliance. Accordingly. the selected structural variables and demographic variables which have influenced sick role behavior of the hypertensive patient must be integrated to teaching and counselling programs for better hypertension control.

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A Study on the Determinant Factors on Return in Internet Clothing Purchase (인터넷 쇼핑에서 의류제품 반품행동 결정요인)

  • Ji, Hye-Kyung
    • Journal of the Korean Society of Clothing and Textiles
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    • v.32 no.12
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    • pp.1891-1902
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    • 2008
  • With concerns for consumers' return behaviors affecting internet shopping malls' profits and product management in the internet clothing market, this study is designed to investigate determinants affecting return and path models for return behaviors. For an empirical study, questionnaires are prepared and respondents in their 20s and 30s with internet clothing purchase experience are selected using the convenience sampling. A total of 517 questionnaires are used for the final analysis. Data are analyzed by using SPSS 12.0 software and descriptive statistics, $x^2$-test, discriminant analysis, regression analysis, and path analysis is conducted. The results are as follows. First, ones who have returned after purchasing clothing items in internet shopping reached 63.4% of the total consumers. Respondents returned items with price at 50 thousand won or less stood at 67.2%, and the most frequent return shopping malls are open markets with their return rate at 51.1%. Second, variables such as risk perception, information search, impulse buying, buying experience, and age have a positive effect on return experience. Impulse buying and buying experience turn out to have a significant effect on the degree of return, but risk perception, information search, age, and gender to have an insignificant effect. Return intention is significantly affected by risk perception, gender, and age. Third, the analysis of path model for return experience shows that perceived risk has a positively effect, and information search has a direct effect as well as an indirect effect through buying experience or impulse buying. The analysis of path model for the degree of return shows that risk perception does not have effect, but information search has indirect effect through buying experience or impulse buying. This study is thought to find consumers' return behavior characteristics in online shopping, and help businesses operating online shopping malls to efficiently manage returns and set up strategies against returns.

A Study on the Effects of Visual Aesthetics and Usability of Web Site Design on their Performance (웹사이트 디자인의 시각적 요소와 유용성이 성과에 미치는 영향에 관한 연구)

  • Kim, Seung-Kyung;Lee, Jae-Kwan
    • Journal of the Korean Operations Research and Management Science Society
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    • v.32 no.2
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    • pp.17-40
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    • 2007
  • Most research on web site design has focused on technological factors, while visual aesthetic factors have been considered less important. In contrast, this study focuses on visual aesthetic factors in web site design. Findings of this study can be summarized as follows : (1) The result of SPSS-factor analysis shows that there are 3 distinct factors, 'classical aesthetics', 'expressive aesthetics', and 'usability' 'Classical aesthetics' and 'expressive aesthetics' can be described by visual aesthetic design, 'Visual aesthetic design' can be distinguished from 'usability'. This conceptual confusion relating to 'usability' and 'visual aesthetic design' can be clarified by these findings. (2) As a result of multiple regression analyses, 'classical aesthetics', 'expressive aesthetics', and 'usability' have a positive influence on 'interactivity' and 'web site evaluation'. This research clarifies the concepts of 'expectations' of Grier [18] and 'engagement' of Rosen and Purinton [33] as the 'interactivity' between users and web sites. Furthermore, this research suggests a valid model with high $R^2$(interactivity, 48% : web site evaluation, 68%). (3) Empirical tests show that the differences among users in 'entry point' are related to the characteristics of web sites and the personal characteristics of users. The differences among users in terms of 'scanning time' are closely related to the attitudes and evaluation tendencies of users with respect to web sites. These findings could contribute to the 'search phase' of the Faraday model [16], enabling it to be more precise and extensible. The managerial implication of this study is that customers' preferences regarding web site designs are differences, as their preferences are based on their individual characteristics. Therefore, marketing managers should consider promotional tools on web sites that are relevant to the target market. An optimal strategy for web design could be a carefully-selected combination of factors that are relevant to the 'interactivity' and 'evaluation' of web sites. Additionally, if marketing managers want to attract more favorable attitudes and more affirmative evaluations from users, web sites should be designed so that they are understood more quickly by users. finally, this study suggests that 'good design' for web sites depends on understanding how to attain the appropriate balance between 'classical aesthetics' and 'expressive aesthetics', based on the target customer.

Sensitivity Analysis of Volcanic Ash Inherent Optical Properties to the Remote Sensed Radiation (화산재입자의 고유 광학특성이 원격탐사 복사량에 미치는 민감도 분석)

  • Lee, Kwon-Ho;Jang, Eun-Suk
    • Korean Journal of Remote Sensing
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    • v.30 no.1
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    • pp.47-59
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    • 2014
  • Volcanic ash (VA) can be estimated by remote sensing sensors through their spectral signatures determined by the inherent optical property (IOP) including complex refractive index and the scattering properties. Until now, a very limited range of VA refractive indices has been reported and the VA from each volcanic eruption has a different composition. To improve the robustness of VA remote sensing, there is a need to understanding of VA - radiation interactions. In this study, we calculated extinction coefficient, scattering phase function, asymmetry factor, and single scattering albedo which show different values between andesite and pumice. Then, IOPs were used to analyze the relationship between theoretical remote sensed radiation calculated by radiative transfer model under various aerosol optical thickness (${\tau}$) and sun-sensor geometries and characteristics of VA. It was found that the mean rate of change of radiance at top of atmosphere versus ${\tau}$ is six times larger than in radiance values at 0.55 ${\mu}m$. At the surface, positive correlation dominates when ${\tau}$ <1, but negative correlation dominates when ${\tau}$ >1. However, radiance differences between andesite and pumice at 11 ${\mu}m$ are very small. These differences between two VA types are expressed as the polynomial regression functions and that increase as VA optical thickness increases. Finally, these results would allow VA to be better characterized by remote sensing sensors.

A study on Chinese Consumer Behavior of Korean Automobiles (중국소비자의 한국자동차 구매의도에 관한 연구)

  • SONG, Yun-Tao;LEE, Jong-Ho
    • The Journal of Industrial Distribution & Business
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    • v.10 no.6
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    • pp.29-37
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    • 2019
  • Purpose - This study intends to analyze Chinese consumers' purchase intention of Korean automobile. The aims of this study investigated to find out how product attributes and brand image affect the consumer's purchase intention of Korean automobiles in China. We consider the product attributes, brand image as evaluation criteria, also recognized as objectives for purchase intention. This study aims to analyze the positive effects on Chinese consumers' purchase intention with the variables by using the research model. Research design, data, and methodology - Based on theory of Purchase Intention, the concept of purchase intention was assessed by two factors: a) product attributes, and b) brand image to test the proposed hypotheses. The survey was conducted for 30 days, from October 17 to November 16 in 2018. With IBM SPSS Statistics 23.0 and IBM SPSS AMOS 23.0, factor analysis and regression, Cronbach's alpha and correlation were tested. 300 samples were used for this analysis. Results - As a main result, product attributes and brand image exerted significant effects on consumer's purchase intention. Thus,

    and

    were supported. The results showed that the product attributes, brand image had positive effects on purchase intention. The findings of this thesis are as follows: Firstly, automobiles' quality factors were divided into two categories like product properties (price, performance, design, economy, and safety), and brand image (awareness, favorability, reliability, and familiarity). Second, it showed that product properties and brand image had positive impacts on purchase intention of consumer. Conclusions - The impact of product attributes and brand image on consumer perceived value of Korean automobiles in China can be seen as a universal psychology of consumers who trust automobile products such as high quality, technology, ets. The results offer some insights into the extended model and have important managerial implications for Korean automobile enterprise. As the findings of this thesis show, all strategic orientations have significant and positive effects on the ability of innovation. At the same time, automobile company must pay attention to quality. As the relationship between the automobiles' performance and brand image were positive and significant, automobile companies should have comprehensive strategic orientations focused on strengthening these factors.

A Study on the Effects of Technology, Marketing, Network Competencies on Rapid Globalization in Korea (한국진출 글로벌 기업의 신속한 글로벌 성과에 관한 영향연구)

  • Han, Sang Seol
    • International Commerce and Information Review
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    • v.16 no.5
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    • pp.319-342
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    • 2014
  • In this paper, we aim to advance our knowledge about factors influencing rapid globalization of firms in Korea. Through analysing empirically, this study focuses on the effect of technology competencies and marketing competencies and network in Korea rapid globalization. The subject of this study was foreign subsidiaries that entered in korea to expand their business overseas. This study are examined by the sample of 186 foreign subsidiaries operating in Korea. The empirical results from structural equation modeling and regression analysis. Our findings show that marketing competencies, technological competencies and network are key drivers of rapid globalization in Korea market. Meanwhile, we also find that marketing competencies related to overseas market development in B2C foreign subsidiaries and technology competencies related to overseas market development in B2B foreign subsidiaries. And it was revealed in the path analysis using AMOS model that the relevancy of the study model was higher for B2C foreign subsidiaries than B2B foreign subsidiaries and the explanatory power(statistic index) revealed to be 31.9% higher for B2C foreign subsidiaries than B2B foreign subsidiaries in the effect relation on the rapid globalization in Korea market. Company type (B2C/B2B) was revealed moderating factor on the rapid globalization. Our study confirmed that marketing, technological competencies and network of firms effects on the rapid globalization in Korea.

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