• Journal of Korean Society of Transportation
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• v.27 no.3
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• pp.81-90
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• 2009

The safety management of a road network comprises four basic inter-related components：identification of sites(black spot) requiring safety investigation, diagnosis of safety problems, selection of feasible treatments for potential treatment candidates, and prioritization of treatments given limited budgets(Persaud, 2001). Identification process of selecting black spot is very important for efficient investigation of sites. In this study, the accident prediction model for EB method was developed by using accident data and geometric conditions of black spots selected from four-leg signalized intersections in In-cheon City for three years (2004-2006). In addition, by comparing the rank nomination technique using EB method to that by using accident counts, we managed to show the problems which the existing method have and the necessity for developing rational prediction model. As a result, in terms of total number of accidents, both the counts predicted by existing non-linear regression model and that by EB method have high good of fitness, but EB method, considering both the accident counts by sites and total number of accident, has better good of fitness than non-linear poison model. According to the result of the comparison of ranks nominated for treatment between two methods, the rank for treatment of almost sites does not change but SeoHae intersection and a few other intersections have significant changes in their rank. This shows that, with the technique proposed in the study, the RTM problem caused by using real accident counts can be overcome.

• Korean journal of applied entomology
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• v.24 no.1 s.62
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• pp.1-6
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• 1985

The data on the striped rice, borer populations, collected in the four years from 1973 to 1976, was reanalyzed to study the characteristics in the aggregation pattern of the insect larvae in the paddy fields. The distribution pattern of the larvae was well fitted to the negative binomial model in both the first and the second generation. With reference to the Green's coefficient of dispersion estimated, the aggregation of the larvae was categorized into three phases: initial high aggregation, changing, and dispersed stable phase. Except the changing phase, each phase in each generation could be defined by a common k. The phase-change was initiated by the larval dispersal between hills of the rice plants: the larvae of the third stage and those of the fifth stage, for the first and second generation, respectively. The characteristics of the aggregation pattern were stable in the second generation. In the first genaration, the pattern was more or less variable, indicating that the life system of the insect in the first generation was more susceptible to the variations of the external physical factors than that in the second generation.

• Korean journal of applied entomology
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• v.52 no.3
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• pp.243-248
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• 2013

This study was conducted to understand the settlement process of Ascotis selenaria larvae into citrus orchards with respect to oviposition site and analysis of the spatial distribution pattern of the larvae. A. selenaria eggs were not found on citrus trees in field and green house, but not on citrus trees in the field. A. selenaria larvae showed a significant clump distribution in the greenhouse. In the open citrus field, the index of dispersion was around 1.0 in most cases, with a weak clumping degree. However, the d-statistic was between -1.96 and 1.96, indicating a statistically significant random distribution. In addition, the Green's index (a clumping index) was very low in all cases, even though the clump distribution was accepted. for most samples, the probability distribution of larval frequency in the field satisfied the probability distribution functions of Poisson (random pattern) and the negative binomial (clump pattern) distribution. In addition, the temporal distribution of the larvae in the open field showed a pattern which was formed by colonizers from outside oviposition sites. Further, the difference in larval spatial distribution between field and greenhouse orchards was discussed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.2
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• pp.397-405
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• 2015

In the past, expressways focused on mobility. However, the paradigm of expressways fuction today has been changed from fast expressways to safe expressways as people's quality of living and consciousness level heightened. In 2012, 3,550 traffic accidents occurred on expressways and 371 people died. The fatality rate of traffic accidents on expressways is almost twice that on general national roads. This study developed accident forecast models (safety performance functions) based on the number of traffic accidents and traffic volumes on six major lines on expressways. It is difficult to forecast safety performance functions for each expressway line because the lines and the scales of expressways are different from each other; therefore, integrated safety performance functions of six lines were determined first, and the coefficients, which can correct the traffic accidents on each line, were calculated. It is believed that this study will contribute in the safer management of expressways by being used as basic information in the establishment of traffic safety strategies for each expressway line in prevention of traffic accidents. Moreover, more studies would be required in the future, which would suggest reliable accident forecasts by calculating correction coefficients by line through integrated models by groups dependent on the characteristics of each line.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.11
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• pp.1818-1827
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• 2018

Objective: The objective of this work was to determine the prevalence of the pathologies that caused the condemnation of pig carcasses in an area of intensive pig farming and Mediterranean climatology and to evaluate their influence in a risk-based inspection procedure for slaughterhouses. Methods: A retrospective observational investigation was carried out from 2002 to 2016 into the pathological processes that caused the condemnation of pig carcasses in a slaughterhouse from South-eastern Spain. The seasonal effect on the causes of condemnation carcass was reported. Negative binomial model was used to evaluate the effect of season on the rate of antemortem rejections and post-mortem condemnations. Histopathological examinations were performed to confirm the diagnosis. Results: The risk of antemortem rejections (0.0564%) was significantly greater in summer (risk ratio [RR] = 1.57). Autumn was associated with higher rate (RR = 1.69) of the total postmortem condemnations (0.1046%). Significantly higher rates of pronounced anaemia (0.0111%) were observed in summer (RR = 3.20). The main causes of anaemia were observed gastroesophageal ulcers and haemorrhagic enteropathies. Significantly highest risk of erysipelas (0.0074%) were observed in autumn (RR = 5.485). About other zoonosis, only eight cases (0.0013%) of carcasses were declared unfit due to tuberculosis lesions. Porcine muscular cysticercosis was not detected. Nevertheless, nonspecific causes such as generalized infections and emaciation represented the half of the condemned carcasses (50.90%). Conclusion: The pathologies leading to the condemnation of carcasses in this study can be considered representative of the pathologies that affect the pig population from a region with a high intensive production and Mediterranean climatology because this slaughterhouse receives a lot of animals from many farms of different size in a high intensive pig production zone (Mediterranean region). Increased knowledge of environmental factors that may foment the appearance of the diseases is essential for implementing inspection programs based on risk assessment in pig's slaughterhouses.

• Knowledge Management Research
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• v.21 no.3
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• pp.67-87
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• 2020

Maintaining active users who repeatedly share high-quality knowledge is critical for the success of online Q&A sites. This study suggests two paths that lead to active users' continuous knowledge sharing: 1) elaborated decision process, represented by continuance intention, and 2) automated cognitive process, represented by past behavior. The direct and moderating effects of continuance intention and past behavior were verified by analyzing subjective intention data and objective behavior data of 333 active users of Naver Knowledge-iN. Using Cox proportional hazards regression and negative binomial regression, the influences of continuance intention and past behavior on two types of continuous knowledge sharing were examined. The results showed that only past behavior was significantly influential on knowledge sharing continuance and as to the frequency of knowledge sharing, both continuance intention and past behavior's influences were significant. It was also confirmed that past behavior negatively moderates continuance intention's effect on the frequency of knowledge sharing. In order to maintain active users' continuous knowledge sharing, it is important to habituate knowledge sharing through repetitive knowledge sharing behavior. And in order to increase the frequency of knowledge sharing, in addition to the habituation, appropriate benefits that can increase the continuance intention should be provided.

• Journal of Distribution Science
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• v.13 no.8
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• pp.97-104
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• 2015

Purpose - This study examines the positive impact of the social distance between producers and users of online content, investigating and analyzing the most popular Web content. In addition, it tries to elicit the matching effect that appears when the individuals'cultural background is consistent with social distance. Research design, data, and methodology - We collected and analyzed actual data about 4,981 videos clips on YouTube, looking at six countries in order to verify the content of this study. Based on the results of the data analysis, the study conducted behavioral measurements on popularity, social distance, culture, and user engagement. The unit of analysis was the content and we collected information about the content producers and the content records. We controlled the views, comments, likes, calendar dates, and ages in the empirical models. The data was collected in 2011, with the records coming from South Korea, Japan, China, U.S., German, and France. A total of 4,980 elements were analyzed in the model. The empirical model estimated is the bivariate negative binomial distribution (NBD) model. Results - It turns out that there is a possibility that the matching effect can be diminished by variables that reflect the psychological involvement of user engagement. This study proposes academic and practical implications based on these research results. This research shows the positive effect of social distance between users and producers on the increased performance of the online content. We find the effect of social distance to be a stronger tendency in collectivism. The collectivists follow their sense of friendship and intimacy in their culture and, the social congruence effect can be found there as well. The effect, however, could erode in a social case where users are motivated by strong intrinsic and psychological factors. In addition, user engagement complicates the process of user decision making regarding the information. Conclusions - This study examines how the differential effects of social distance caused by culture could disappear through user commitment as a complicated user motivation. Some potential implications are as follows. First, a firm in the collectivism culture has to communicate based on the social distance. In fact, most online channels do not have a function that indicates the social distance as measured by favorites or subscribers. This function could help increase the performance of the content in online channels, but this increasing effect can only be found in a collectivist culture. Based on this, the firms have to communicate and announce to users the actual social distance between users and producers. Second, firms should develop a system that discovers the social distance and culture and shows these measures to users and producers, since the congruence effect between social distance and culture is found only for low user engagement. The firms can take the advantage of the congruence effect only for the development of the social distance and culture visualized system.

• International Journal of Highway Engineering
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• v.14 no.2
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• pp.145-155
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• 2012

At present, Seoul City is putting the bus exclusive lane system into practice according to mass transit revitalization policy. Starting with the installation of roadside bus exclusive lane in the past, at present, even the road sections for central- lane bus exclusive lane system are on the increase. The purpose of this research is to analyze the factors giving impacts on bus accident on central bus exclusive lane and roadside bus exclusive lane. In case of the central bus exclusive lane, the 6 variables, such as the number of bus routes, number of access & entrance to central lanes patterns, whether the stop line of central lanes retreats or not, separated distance between the stop line of central lanes and crosswalks, traffic volume, and number of bus routes stopping at bus stops on reversible lanes, were found to have a significant influence on bus accidents. In case of roadside bus exclusive lane sections, the four variables such as the number of right-turn bus routes, whether to be chronic illegal parking & stopping, time for the walk signal, and forms of land use, etc. were found to have a significant influence on bus accident.

• International Journal of Highway Engineering
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• v.14 no.2
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• pp.131-143
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• 2012

The past researches on roadway segment safety estimation focused on intersections, which are the primary traffic accident regions. The past researches on roadway segments, However, analyzed the effects of certain factors on the traffic accident occurrence rate by organizing the individual geometric structures of the roads, and there is still a dearth of researches on the development of a traffic accident estimation model for rural roadway segments. Therefore, this research focused on rural two-lane and multilane roadway segments and developed traffic accident estimation models through the application of statistical techniques. This is required to explain such high frequency of zero counts in the traffic accident data. In this research, it was found that the Hurdle model is more suitable than the Poisson or negative binomial-regression model for explaining the excess zeros case. In addition, main variables were chosen to estimate their effects on traffic accident occurrence at rural roadway segments, and the safety at such rural roadway segments was estimated. In this research, it was assumed that there are different factors that affect the safety at two-way lane and multilane roadway segments, and a traffic accident estimation model was developed by dividing the two-way lane and multilane roadway segments.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.2
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• pp.211-219
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• 2015

Objectives: We aimed to examine the association between experience of workplace violence and musculoskeletal pain among wage workers in South Korea. Methods: We analyzed a cross-sectional survey of 29,601 wage workers from the third wave Korean Working Conditions Survey in 2011. Experience of workplace violence was assessed through three questions, "Over the past 12 months, have you ever experienced: (1) physical violence, (2) bullying, or (3) sexual harassment at workplace?" Musculoskeletal pain was measured using the three questions, "Over the past 12 months, have you ever experienced: (1) low back pain, or (2) upper limb pain(i.e. shoulder, neck, and arm), or (3) lower limb pain(i.e. hip, leg, knee, and foot)?" Wage workers could answer 'Yes' or 'No' to each of the three questions. Multivariate negative binomial regression was applied to examine the association between workplace violence and musculoskeletal pain after adjusting for confounders including self-reported physical work factors. All analyses were performed using STATA/SE version 13.0. Results: Physical violence was associated with low back pain(PR: 2.16, 95% CI: 1.77, 2.65), upper(PR: 1.65, 95% CI: 1.45, 1.88) and lower limb pain(PR: 1.81, 95% CI: 1.52, 2.15) among male wage workers whereas it was related to upper(PR: 1.86, 95% CI: 1.53, 2.26) and lower limb pain(PR: 2.95, 95% CI: 2.47, 3.53) among female wage workers. Significant association was observed between sexual harassment and upper(PR: 1.25, 95% CI: 1.01, 1.56) and lower limb pain(PR: 2.41, 95% CI: 1.97, 2.93) among female wage workers whereas the association was only significant in the analysis with lower limb pain(PR: 1.87, 95% CI: 1.17, 2.97) among male wage workers. Bullying was associated only with lower limb pains among both male(PR: 1.77, 95% CI: 1.32, 2.37) and female(PR: 2.10, 95% CI: 1.69, 2.61) wage workers. Conclusions: This study found that experience of workplace violence, particularly physical violence and sexual harassment, was associated with musculoskeletal pain among Korean wage workers.