PURPOSES : The main purpose of this study is to identify directions for improvement of triangular islands installation warrants through analysis of the characteristics of crashes and severity with and without triangular islands on intersections. METHODS : The data was collected by referring to the literature and analyzed using statistical analysis tools. First, an independence test analyzed whether statistically significant differences existed between crashes depending on the installation of triangular islands. As a result of the analysis, individual prediction models were developed for cases with significant differences. In addition, each crash factor was derived by comparison with each model. RESULTS : Significant differences appeared in the "crash frequency of serious or fatal" and "crash severity" owing to the installation of triangular islands. As a result of comparing crash factors through the individual models, it was derived that the differences were dependent on the installation of the triangular islands. CONCLUSIONS : As a result of reviewing previous studies, it is found that improving the installation warrants of triangular islands is reasonable. Through this study, the need to consider the volume and composition ratio of right-turn vehicles when installing a triangular island was also derived; these results also need to be referred to when improving the triangular island installation warrants.

PURPOSES : In this study, the main factors affecting the severity of traffic accidents among elderly drivers were reviewed, and accident factors with a high accident risk were analyzed. This provided basic data for preparing a traffic safety system for elderly drivers and establishing policies. METHODS : Based on machine learning, the major factors influencing accident severity (from the analysis of traffic accident data for elderly drivers) were analyzed and compared with existing statistical analysis results. The machine learning algorithm used the Scikit-learn library and Python 3.8. A hyperparameter optimization process was performed to improve the safety and accuracy of the model. To establish the optimal state of the model, the hyperparameters were set (K = 5) using K-fold cross-validation. The hyperparameter search applied the most widely utilized grid search method, and the performance evaluation derived the optimal hyperparameter value using neutral squared error indicators. RESULTS : The traffic laws, road sections of traffic accidents, and time zones of accidents were analyzed for accidents involving elderly drivers in Daejeon Metropolitan City, and the importance of the variables was examined. For the analysis, a linear regression model, machine learning-based decision tree, and random forest model were used, and based on the root mean square error, the random forest accuracy performance was found to be the best. Ultimately, 18 variables were analyzed, including traffic violations, accident time zones, and road types. The variables influencing the accident severity were the speed, signal violation, intersection section, late-night driving, and pedestrian protection violation, with the relative importance of the variables in the order of speed (0.3490966), signal violation (0.285967), and late-night driving (0.173108). These can be seen as variables related to the expansion of life damage owing to physical aging and reduced judgment abilities arising from decreases in cognitive function. CONCLUSIONS : Restricting the driving of the elderly on the expressway and at night is reasonable, but specific standards for driving restrictions should be prepared based on individual driving capabilities.

Background: Pronated foot posture (PFP) contributes to excessive dynamic knee valgus (DKV). Although foot orthoses such as medial arch support (MAS) are widely and easily used in clinical practice and sports, few studies have investigated the effect of MAS on the improvement of DKV during stair descent in individuals with a PFP. Moreover, no studies reported the degree of improvement in DKV according to the severity of PFP when MAS was applied. Objects: This study aimed to examine the immediate effect of MAS on DKV during stair descent and determine the correlation between navicular drop distance and changes in DKV when MAS is applied. Methods: Twenty individuals with a PFP (15 males and five females) participated in this study. The navicular drop test was used to measure PFP severity. The frontal plane projection angle (FPPA) was calculated under two conditions, with and without MAS application, using 2-dimensional video analysis. Results: During stair descent, the FPPA with MAS (173.1° ± 4.7°) was significantly greater than that without MAS (164.8° ± 5.8°) (p < 0.05). There was also a significant correlation between the navicular drop distance and improvement in the FPPA when MAS was applied (r = 0.453, p = 0.045). Conclusion: MAS application can affect the decrease in DKV during stair descent. In addition, MAS application should be considered to improve the knee alignment for individuals with greater navicular drop distance.

The severity of acute pancreatitis (AP) is classified into mild, moderately severe, and severe, considering the presence and duration of organ failure and local complications. Since patients with AP show a large difference in mortality and morbidity according to AP severity, evaluation of the severity of patients with AP in the early stage is important for predicting the prognosis and determining treatment plans including transfer to the intensive care unit or advanced facilities. In order to evaluate the initial severity of AP, it is necessary to confirm the presence of organ failure and objective evaluation using imaging or clinical examinations. In this guideline, it is recommended that evaluation using various severity indices such as bedside index for severity in acute pancreatitis (BISAP), systemic inflammatory response syndrome (SIRS), and acute physiology and chronic health evaluation (APACHE)-II scores be considered.

급성 췌장염은 사망에 이를 수 있는 질환으로, 발병 초기 2주 내 기관부전으로 인한 사망과 이후 몇 주 혹은 몇 달 후 기관부전과 국소 합병증의 문제로 사망하는 두 개의 국면을 보인다. 중증 급성 췌장염을 예측하기 위한 다양한 임상 평가 및 다원적 평가 척도, 영상 검사 및 분자 혈청 검사가 있으나, 현재 가장 우월하게 급성 췌장염의 중증도를 예측하는 척도와 검사가 없고, 사망의 시기를 구분하지 않는 경우가 대부분으로 향후 대규모 연구를 통해 사망의 시기 및 예후를 예측하는 평가 척도의 개발이 필요하다.

PURPOSES : For vehicle-alone accidents with a high mortality rate, it is necessary to analyze the factors influencing the severity of roadside fixed-object traffic accidents. METHODS : A total of 313 roadside fixed obstacle traffic accidents, variables related to fixed obstacles, and variables related to road geometry were collected. The estimation model was constructed with data collected using an ordinal probit regression model. RESULTS : Piers, vertical slopes, and distances between roads and objects were the primary causes of increased accident severity. CONCLUSIONS : Countermeasures, such as object removal, relocation, clear zones, frangibles, breakaway poles, etc., are required for accident-prone or dangerous points.

Service failure of high severity can lead to high recovery satisfaction when recovery efforts are seen very fair. Customers satisfied with recovery efforts and displaying high attachment anxiety will continue to repurchase. Attachment avoidance did not have an impact on the behavioural intentions and neither did the brand authenticity perception.

PURPOSES: The purpose of this study is to investigate factors that affect the severity of children’s traffic accidents using the ordered probit model, and to contribute to a safer road environment for children. METHODS: This study used children’s traffic accident data during the last four years in the Incheon Metropolitan area. At this point, to analyze only the direct damage caused to children, the analysis was made of accidents where the victim was under 13 years old. Data from a total of 1,110 accidents was collected. When the model was constructed, as it was judged that there could be a difference in factors affecting accident occurrence depending on the zone characteristics, the model was divided into school and non-school zones. RESULTS: The accident content (severity) is divided into four stages (fatal injury, serious injury, minor injury and injury report) to construct the order-typed probit model. For the analysis, 65 variables of 17 categories were included in the model. The statistical package STATA 13.1 was used to analyze the variables affecting the accident severity with a confidence level of 90% (α·=0.1). Consequently, a total of 15 variables were found to have a statistically significant effect on accident severity in a school zone. In contrast, a total of 22 variables were found to have a statistically significant effect on accident severity in non-school zones. Four variables (daytime, weekday, victim age, intersection) were significant in both models. CONCLUSIONS: Among the significant variables found in school zones, signal violation and type of vehicle (line bus, rent car, bus, business other vehicles) had a relatively greater effect on the accident severity than the other variables. In non-school zones, eight variables comprising daytime, head-on collision, crossing, over-speed, gender of victim (male), victim age, type of vehicle (construction machinery), driver age (50-59) were found to be significant variables. In conclusion, as well as eliminating factors that can lead to accident reductions, it is necessary to consider zone characteristics to reduce the severity of children’s accidents and promote children’s traffic safety.

PURPOSES: This study aims to contribute to a better road environment, which can result in accident reduction from two-wheeled vehicles, by analyzing factors affecting the two-wheeled vehicles’ accident severities in Incheon Metropolitan City. METHODS: In this study, the two-wheeled vehicles’ accident severity was classified into four categories (fatal injury, serious injury, minor injury, and injury report) as a dependent variable, and 97 independent variables out of 14 categories were considered to construct an ordered probit model. To determine the factors affecting accident severity, the statistical package LIMDEP was used. RESULTS: Among the variables used in the analysis, variables related to accident occurrence date (first quarter), region (8-district), accident type (passing the edge of the road of the vehicle for a pedestrian accident, fixed object collision, and overturn of vehicle-only accident), violation type (unobtained safety distance, failure to perform safe driving, violation of intersection driving, and violation of others), the type of road (at the intersection, near the intersection, at the crosswalk, near the crosswalk, etc.), gender of assailant (male), vehicle of victim (pedestrian and motorcycle), and age of victim (under 20) were found to have a statistically significant effect on the severity of the accident. CONCLUSIONS: The variables related to accident type (fixed object collision and overturn of vehicle-only accident), gender of assailant (male), and vehicle of victim (pedestrian and motorcycle) have turned out increasing the accident severity. In addition, accident occurrence for two-wheeled vehicles is more diverse and vulnerable to damage than automobile accidents. Therefore, it is time to recognize the seriousness of two-wheeled vehicle accidents and to improve the environment and systems for safe driving.

Wildfire, which may effect on the spatial distribution of many insects, is one of important disturbances in forests. Because Monochamus beetles are known as vector insects of pine wood nematodes in Korea and burned pine trees can be used as oviposition habitats for Monochamus beetles, we investigated the changes in spatial and temporal distributions of M. alternatus and M. saltuarius across fire severity classes. We also studied other saproxylic beetles, such as cerambycid, scolytid, and bark beetles, which are potential insect pests for pine trees. Study area was classified by fire severity, such as unburned, light (<25% burned), moderate (25~75%), and severe (>75%). Spatial distribution of saproxylic beetles were significantly related to the fire severity.

Wildfire is one of important disturbances in forests, which may effect on insects distribution. In Sangju, about 13 haof pine forests was burned in March, 2017. We investigated the response of insects to fire severity in burned pine forests,Sangju. Study area was classified by fire severity as 5 classes, such as unburned, light, light-moderate, moderate-severe,and severe. We placed 4 multi-funnel traps in each fire severity class. A total of 729 insects belonging to 42 specieswere collected during May 24 to October 12, 2017. Spondylis buprestoides (447 individuals), Sipalinus gigas (50 individuals),and Acanthocinus carinulatus (43 individuals) were dominant species accounted for 74.1% of total. According to fire severity,abundance and species richness were increased with fire severity, especially in high-medium area. Interestingly, two Monochamusspecies, vector insects of pine wood nematodes, were more caught in more severed area than in other classes.

Purpose: The study was to investigate the effect of fatigue severity on dry eye syndrome in adults. Methods: Structured questionnaires were used for 365 adults (97 males, 268 females), participants of sex, age, ocular history including basic population, sociological variables and with the investigation of lifestyles, including, were to write to self-evaluate FSS (Fatigue Severity Scale), OSDI (Ocular Surface Disease Index). Results: The mean fatigue severity of 365 subjects was examined as 4.52 ± 1.37. When divided by 3.22 into the low fatigue group and the high fatigue group as node, the low fatigue group was 19.5% (71 people) and the high fatigue group was 80.5% (294 people). The prevalence of dry eye syndrome was 88.8% (324 people), mild 21.6% (79 people), moderate 15.9% (58 people) and severe 51.3% (18 people). Dry eye syndrome was on the severity of the low fatigue group in severe 29.6% (21 people), moderate 21.1% (15 people), mild 32.4% (23 people), normal 16.9% (12 people), in the high fatigue group severe 56.5% (166 people), moderate 32.5% (23 people), mild 19.1% (56 people), normal 9.9% (29 people). Dry eye syndrome was significantly different according to fatigue severity (F = 70.851, P = 0.000). Conclusions: The results of the analysis of the effect of dry eye syndrome according to fatigue severity showed that the higher the fatigue, the more eye fatigue is considered to be dry.

OBJECTIVES : Fixed roadside objects are a threat to drivers when their vehicles deviate from the road. Therefore, such roadside objects need to be suitably dealt with to decrease accidents. This study determines the factors affecting the severity of accidents because of fixed roadside objects. METHODS : This study analyzed the crash severity impact of fixed roadside objects by using ordered probit regression as the analysis methodology. In this research, data from 896 traffic accidents reported in the last three years were used. These accidents consisted of sole-car accidents, fixed roadside object accidents, and lane-departure accidents on the national highway of Korea. The accident severity was classified as light injury, severe injury, and death. The factors relating to the road and the driver were collected as independent variables. RESULTS: The result of the analysis showed that the variables of the crash severity impact are the collision location (left side), gender of the driver (female), alcohol use, collision facility (roadside trees, traffic signals, telephone poles), and type of road (rural segments). Additionally, the collision location (left side), gender of the driver (female), alcohol use, collision facility (street trees, traffic signals, telephone poles), and type of road (rural segments), in order of influence, were found to be the factors affecting the crash severity in accidents due to fixed roadside objects. CONCLUSIONS: An alternative solution is urgently required to reduce the crash severity in accidents due to fixed roadside objects. Such a solution can consider the appropriate places to install breakaway devices and energy-absorbing systems.

PURPOSES : Low visibility caused by dark surroundings at nighttime affects the likelihood of accidents, and various efforts, such as installing road safety facilities, have been made to reduce accidents at night. Despite these efforts, the nighttime severity index (SI) in Korea was higher than the daytime SI during 2011-2014. This study determined the factors affecting daytime and nighttime accident severity through a discriminant analysis. METHODS: Discriminant analysis. RESULTS: First, drowsiness, lack of attention, and lighting facilities affected both daytime and nighttime accident severity. Accidents were found to be caused by a low ability to recognize the driving conditions and a low obstacle avoidance capability. Second, road conditions and speeding affected only the daytime accident severity. Third, failure to maintain a safe distance significantly affected daytime accident severity and nonsignificantly affected nighttime accident severity. The majority of such accidents were caused by rear-end collisions of vehicles driving in the same direction; given the low relative speed difference in such cases, the shock imparted by the accidents was minimal. CONCLUSIONS: Accidents caused by a failure to maintain a safe distance has lower severity than do accidents caused by other factors.

급성 췌장염은 중증도가 높은 경우 생명을 위협할 수 있는 심각한 질환이다. 2012년 개정된 아틀란타 분류법에 의하면 경증, 중등증, 중증 급성 췌장염으로 분류되며, 중증 급성 췌장염의 임상경과는 초기 및 후기로 구분될 수 있다. 췌장염 으로 인한 사망은 대부분 입원 후 7-14일 이내에 발생하며 급격하게 장기부전을 일으키면서 발생한다. 특히 입원시 높은 APACHE II 점수를 가지는 중증 급성 췌장염 환자에서 초기 에 48시간 이상 장기부전이 지속되는 경우 사망률이 더 높다. 따라서 중증 급성 췌장염으로 진행하거나 위험도가 높은 환자를 선별하는 것은 치료에 중요하다. 이를 위하여 여러 가지 점수 체계를 이용한 예측방법이 개발되었으나 장단점 을 내포하고 있다.

PURPOSES: The objective of this study is to analyze factors affecting traffic accident severity for determining countermeasures on freeway climbing lanes. METHODS : In this study, an ordered probit model, which is a widely used discrete choice model for categorizing crash severity, was employed. RESULTS: Results suggest that factors affecting traffic accident severity on climbing lanes include speed, drowsy driving, grade of uphill 3%, gender (male offender and male victim), and cloud weather. CONCLUSIONS : Several countermeasures are proposed for improving traffic safety on freeway climbing lanes based on the analysis of crash severity. More extensive analysis with a larger data set and various modeling techniques are required for generalizing the results.

PURPOSES: The purpose of this study is to verify traffic accident injury severity factors for elderly drivers and the relative relationship of these factors. METHODS: To verify the complicated relationship among traffic accident injury severity factors, this study employed a structural equation model (SEM). To develop the SEM structure, only the severity of human injuries was considered; moreover, the observed variables were selected through confirmatory factor analysis (CFA). The number of fatalities, serious injuries, moderate injuries, and minor injuries were selected for observed variables of severity. For latent variables, the accident situation, environment, and vehicle and driver factors were respectively defined. Seven observed variables were selected among the latent variables. RESULTS: This study showed that the vehicle and driver factor was the most influential factor for accident severity among the latent factors. For the observed variable, the type of vehicle, type of accident, and status of day or night for each latent variable were the most relative observed variables for the accident severity factor. To verify the validity of the SEM, several model fitting methods, including , GFI, AGFI, CFI, and others, were applied, and the model produced meaningful results. CONCLUSIONS: Based on an analysis of results of traffic accident injury severity for elderly drivers, the vehicle and driver factor was the most influential one for injury severity. Therefore, education tailored to elderly drivers is needed to improve driving behavior of elderly driver.