• Journal of Technology Innovation
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• v.18 no.1
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• pp.75-98
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• 2010

The purpose of this paper is to give policy implications for relevant policy-makers by analyzing factors affecting performance of industrial R&D programs of the Ministry of Knowledge Economy. The independent variables are type of project leader organization(Big Enterprises, SMEs, Ventures Businesses, Public Research Institutions, Universities), cooperative or noncooperative R&D among industry-university-research institution, total number of project participant organization, total R&D investment, and the ratio of private investment to total R&D investment. The dependent variables are domestic or foreign patents granted and domestic or foreign papers accepted. The method of analysis is Poisson Regression analysis operated by STATA. The results of this research are follows ; Universities show higher R&D performance compared to enterprises or public research institutions in terms of patents and papers as well. Venture businesses show higher patent performance compared to SMEs. Inverted U-shaped relationship between total number of project participant organization and R&D performance is not supported. The higher total R&D investment, the higher R&D performance. The higher the ratio of private investment to total R&D investment, the higher R&D performance.

• Journal of Korean Society of Transportation
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• v.30 no.6
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• pp.93-102
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• 2012

The frequency and severity of traffic accidents related to signalized intersections in urban areas have been more serious than those in both arterial segments and crosswalks. Especially, traffic accidents involved with injuries and fatalities have caused by traffic signal violations within intersections. Therefore, many countries including Korea have installed the red light enforcement camera (RLE) to reduce traffic accidents associated with the traffic signal violation. Meanwhile, many methodologies have been studied in terms of safety impacts estimation of red light enforcement, which, however, cannot be easy to conduct. In this study, safety impacts was estimated for intersections of Chicago downtown area using SPF models and EB approach. As a result, for all crash types and target traffic accident types such as "angle", "rear end", "sideswipe in the same and other directions", "turn", and "head on", fatal crashes were reduced by 26% and 38%. However, RLE may increase property-demage-only-crashes by 3.23% and 1.16%, respectively.

• Journal of Korean Society of Transportation
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• v.28 no.2
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• pp.123-133
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• 2010

The national standards for the installation of pedestrian crosswalks prohibits installation of crosswalks within 200 meters of nearby overpasses, underpasses, or crosswalks. In case the exceptional installation is required, the feasibility study is to be thoroughly conducted by the local police agency. However, it is an undeniable fact that the specific installation standards for optimal types and locations of crosswalks are not yet to be established. This paper examines the development of traffic accident prediction model applicable to different types and locations of bus stops(type A and type B) at mid-block intersections. Furthermore, it develops the poisson regression model which sets the "number of traffic accidents" and "traffic accident severity" as dependent variables, while using "traffic volumes", "pedestrian traffic volumes" and "the distance between crosswalks and bus stops" as independent variables. According to the traffic accident prediction model applicable to the type A bus stop location, the traffic accident severity increases relative to the number of traffic volumes, the number of pedestrian traffic volumes, and the distance between crosswalks and bus stops. In case of the type B bus stop model, the further the bus stop is from crosswalks, the number of traffic accidents decreases while it increases when traffic volumes and pedestrian traffic volumes increase. Therefore, it is reasonable to state that the bus stop design which minimizes the traffic accidents is the type C design, which is the one in combination of type A and type B, and the optimal distance is found to be 65 meters. In case of the type A design and the type B design, the optimal distances are found to be within range 60~70meters.

• The Journal of the Korea Contents Association
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• v.17 no.5
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• pp.479-490
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• 2017

The objective of this study is to examine the association of social networks and medical care utilization of elderly living alone depending on self-rated health status, and also to measure the moderating effects of welfare services for elderly. To this purpose, the data which was collected from the 2014 National Survey on Elderly in Korea was analyzed by Chi-square test and Poisson regression. According to the results, social networks and elderly welfare services affected to medical care utilization of elderly living alone, only who aware of their self-rated health status as bad. With this group, the frequency of contact with family and participation in lifelong education had a significant effect on increasing medical care utilization. In contrast, the frequency of contact with neighbors and the participation in elderly employment program were significant to reduce the utilization of medical care. Furthermore, the moderating effects of elderly welfare services were also measured that formal social gathering has an effect of increasing the medical care utilization of elderly living alone by expansion of their social networks. Based on these results, this study consequently has an implication for suggesting expansion of elderly welfare services, which might be an alternative to social networks of elderly living alone, and also for seeking the direction of political intervention that helps health promotion and disease prevention through the research of medical care utilization.

• Journal of Veterinary Clinics
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• v.36 no.1
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• pp.7-14
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• 2019

In South Korea, six large outbreaks of highly pathogenic avian influenza (HPAI) have occurred since the first confirmation in 2003 from chickens. For the past 15 years, HPAI outbreaks have become an annual phenomenon throughout the country and has extended to wider regions, across rural and urban environments. An understanding of the spatial epidemiology of HPAI occurrence is essential in assessing and managing the risk of the infection; however, local spatial variations of relationship between HPAI incidences in Korea and related risk factors have rarely been derived. This study examined whether spatial heterogeneity exists in this relationship, using a geographically weighted Poisson regression (GWPR) model. The outcome variable was the number of HPAI-positive farms at 252 Si-Gun-Gu (administrative boundaries in Korea) level notified to government authority during the period from January 2014 to April 2016. This response variable was regressed to a set of sociodemographic and topographic predictors, including the number of wild birds infected with HPAI virus, the number of wintering birds and their species migrated into Korea, the movement frequency of vehicles carrying animals, the volume of manure treated per day, the number of livestock farms, and mean elevation. Both global and local modeling techniques were employed to fit the model. From 2014 to 2016, a total of 403 HPAI-positive farms were reported with high incidence especially in western coastal regions, ranging from 0 to 74. The results of this study show that local model (adjusted R-square = 0.801, AIC = 954.5) has great advantages over corresponding global model (adjusted R-square = 0.408, AIC = 2323.1) in terms of model fitting and performance. The relationship between HPAI incidence in Korea and seven predictors under consideration were significantly spatially non-stationary, contrary to assumptions in the global model. The comparison between global Poisson and GWPR results indicated that a place-specific spatial analysis not only fit the data better, but also provided insights into understanding the non-stationarity of the associations between the HPAI and associated determinants. We demonstrated that an empirically derived GWPR model has the potential to serve as a useful tool for assessing spatially varying characteristics of HPAI incidences for a given local area and predicting the risk area of HPAI occurrence. Considering the prominent burden of HPAI this study provides more insights into spatial targeting of enhanced surveillance and control strategies in high-risk regions against HPAI outbreaks.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.6
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• pp.124-140
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• 2023

The rapid growth in shared E-scooters worldwide has led to many studies on the topic. The results of these studies are still in the early stages, and the main factors affecting trips are being identified. In particular, the development of trip-generation models is very important for transportation planning, and a new transportation mode for developing the models for shared E-scooters is lacking both domestically and internationally. This study aims to develop a trip generation model for shared E-scooters using significant variables by thoroughly reviewing previous studies. The trip characteristics of major service areas and other areas may differ owing to the trip characteristics of the mode. The trip generation models were developed based on the service trip density by dividing the areas by service level. The factors affecting shared E-scooter trips in major service areas included the presence of universities, closeness centrality, and cultural areas, while factors affecting the trips in minor service areas included the presence of universities, betweenness centrality, and trip distance. The developed models provide basic information that can be used to establish transport policies for introducing shared E-scooters in cities in the future.

• Korean Journal of Psychosomatic Medicine
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• v.28 no.2
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• pp.161-167
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• 2020

Objectives : Although the seasonality of suicide is a well-known phenomenon, little is reported about the seasonality of non-suicidal self-injury. The purpose of this study was to identify the seasonality of wristcutting behavior and to examine its relationship with meteorological factors. Methods : To identify the presence of seasonality, we investigated whether there was a difference in the average number of visits per month to an emergency room (ER) of an urban hospital for 226 patients with wrist-cutting behavior enrolled between December 2014 and May 2019. To ascertain significant meteorological factors, we used the multiple Poisson regression using generalized additive model with time, monthly temperature, monthly sunshine hour, and atmospheric pressure in the prior month as explanatory variables. Results : In males, the average number of monthly visits to the ER for wrist cutting behavior differed by month and was the highest in September (male : p=0.048, female : p=0.21, total : p=0.28). As a result of multiple regression analysis, the average number of patients admitted to the ER for wrist cutting behavior was related to the interaction between atmospheric pressure in the prior month and temperature in males (p=0.010), and showed a positive correlation with sunlight in females [p=0.044, β=4.70×10-3, 95% CI=(1.19×10-4, 9.27×10-3)]. Conclusions : Wrist cutting behavior shows seasonality in male, which is associated with changes in meteorological variables.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.6 no.2
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• pp.120-128
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• 2003

Purpose: Recently, while the authors were experiencing that the epidemic period of rotaviral infection happened more in the early spring, we tried to find out how the outbreaks of rotaviral infection are changing in detail depending on the weather condition since it has something to do with the climate factors and PM10. Methods: Fourteen hundreds seventy nine patients who were proved to be positive to rotavirus were chosen among children less than 5 years old from January 1995 to June 2003. Among various climate factors, monthly average temperature, humidity, rainfall and PM10 were selected. Results: Rotaviral infection was most active in 2002 as 309 (20.9%) patients. It has been the spring that is the most active period of rotaviral infection since 2000. The temperature (RR=0.9423, CI=0.933424~0.951163), rainfall (RR=1.0024, CI=1.001523~1.003228) and PM10 (RR=1.0123, CI=1.009385~1.015248) were significantly associated with the monthly distribution of rotaviral infection. Conclusion: Through this study we determined that the epidemic period of rotaviral infection is changed to spring, which is different from the usual seasonal periods such as late fall or winter as reported in previous articles. As increased PM10 which could give serious influence to the human body, and changing pattern of climate factors such as monthly average temperature and rainfall have something to do with the rotaviral infection, we suppose that further study concerning this result is required in the aspects of epidemiology, biology and atmospheric science.