• Journal of Korean Society of Transportation
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• v.29 no.5
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• pp.7-17
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• 2011

Traffic problems caused by drunk drivers have been steadily raised from the past. Even though the previous researches have focused on the development of countermeasures for preventing drunk driving, the number of drivers violating the DUI (Driving-Under-Influence) regulation is still increasing. Many studies seek countermeasures for preventing drunk driving by comparing the differences between general and drunk drivers. However, few researches have investigated focusing only on the characteristics of drunk drivers. It is well known that characteristics of general drivers are different from those of drunk drivers, and also habitual drunk drivers have different characteristics from non-habitual drunk drivers. Motivated by this fact, only the drivers who have violated DUI regulation are considered in the analysis. This study primarily aims to provide alternative solutions for reducing habitual drunk drivers who are highly inclined to do drunk driving repeatedly. For the analysis, various types of variables potentially effecting drunk driving behavior were investigated, and then truncated count data models were developed to analyze the effects of the variables selected on drunk driving. The results showed that 1) a truncated negative binomial model is better fitted to the data; and 2) five variables including experiential learning, the lack of self-control, self-reflection, the fear of crackdown, and the level of dependence on vehicles were found to be statistically significant.

• 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.

• Journal of the Korean Data Analysis Society
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• v.20 no.6
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• pp.2941-2951
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• 2018

The purpose of this paper is to analyse the effect of ocean weather factors on shipments of swimming crab. We use the data of data portal and ocean weather factors (mean wind velocity, mean atmospheric pressure, mean relative humidity, mean air temperature, mean water temperature, mean maximum wave height, mean significant wave height, maximum significant wave height, maximum wave height, mean wave period, maximum wave period). We did statistical analysis using Poisson regression analysis and negative binomial regression analysis. As the result of study, important factors influential in the shipments of swimming crab turn out to be mean wind velocity, mean atmospheric pressure, mean relative humidity, mean water temperature, maximum wave height, mean wave period and maximum wave period. the shipments of swimming crab increases as mean wind velocity, mean atmospheric pressure, mean relative humidity, mean water temperature increases or mean wave period increase. However, as maximum wave height, maximum wave period decreases, the shipment of swimming crab increases.

• The Journal of the Acoustical Society of Korea
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• v.17 no.7
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• pp.22-27
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• 1998

본 논문에서는 ETRI에서 개발한 가변 어휘 음성 인식기의 어휘 독립 음향 모델링 방법을 기술하고, 이 모델의 어휘 종속, 어휘 독립 및 어휘적응 성능을 평가하기 위하여 다 양한 고립단어 및 연속음성 DB에 대하여 실험한 결과를 분석하였다. 평가를 위하여 사용한 음성 DB로는 고립단어 음성으로 POW(Phonetically Optimized Words) 3848, PBW(Phonetically Balanced Words) 445, PBW 452, 호텔예약 244 단어, 게임 제어용 단어 등이며, 연속음성으로 일반 문장 음성 및 연속 숫자음을 이용하였다. 성능 분석 결과 40개 음소 모델만으로도 비교적 높은 인식률을 보여 주었지만, 어휘독립의 경우는 어휘종속에 비 하여 성능이 크게 낮았고, 특히 대상 어휘가 숫자음, 알파벳, 연속음 등의 경우에는 POW 데이터나 PBW 데이터만 가지고는 우수한 가변 어휘 음성 인식기를 구현하기에 한계가 있 음을 알 수 있다. 또한, 훈련 데이터의 어휘와 평가데이터의 어휘가 비슷할 경우에는 변이음 모델을 사용하면 음소 모델만을 사용할 경우에 비하여 그 성능이 우수하였지만, 일반적인 어휘독립의 상황에서는 효과가 별로 없음을 알 수 있었다.

• Journal of the Economic Geographical Society of Korea
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• v.19 no.1
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• pp.1-17
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• 2016

This paper attempts to explore the spatial structure of inventor networks and their determinants among 230 shi-gun-gu regions in Korea by investigating the residence of co-inventors engaged in Korean patent applications to the Korean Intellectual Office and exploiting a zero inflated negative binomial model to accommodate an estimation to the count nature of a dependent variable and its excess of zeros. Several variables are found to affect the spatial linkage of inventor networks. Spatial links extend beyond the region if it has more own R&D-related specific assets (private R&D, patent productivity, population, education); if it is physically close to and has technological similarity with the other region. The assets of the other region plays a positive role if, in a similar way, the other region has more R&D-related specific assets.

• The Journal of the Korea Contents Association
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• v.13 no.3
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• pp.152-161
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• 2013

This study attempted to test the causal effect of structural characteristics of metropolitan neighborhoods on crime, based on the ecological model of crime explanation. To this end, a Negative Binomial Regression analysis was performed for Seoul's 424 Dong Districts. Results showed that the incidence of homicide increases as much as the scales of economic disadvantage, family disruption, and commercial land use go worse. It suggested that family integrity is one of the most strong and consistent factors that could deter crime in neighborhood's contexts. Economic disadvantage and commercial land use were also critical targets as crime-generating factors. Reasoning with the results of past studies implied that neighborhood-specific approaches need to be developed for effective crime prevention. Although a few limitations could raise a caveat against such interpretation of the results, the value of this research would not be simply denied as the first attempt to utilize all Dong districts of Seoul. It is expected that this study contributes to activating Dong level research and developing effective crime control policy.

• Journal of Korean Society of Transportation
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• v.25 no.3
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• pp.123-135
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• 2007

The objective of this study is to analyze the relationship between traffic accidents occurring at trumpet interchange ramps according to accident type as well as the relevant factors that led to the traffic accidents, such as geometric design elements and traffic volumes. In the process of analysis of the distribution of traffic accidents, negative binomial distribution was selected as the most appropriate model. Negative binomial regression models were developed for total trumpet interchange ramps, direct ramps, loop ramps and semi-direct ramps based on the negative binomial distribution. Based upon several statistical diagnostics of the difference between observed accidents and predicted accidents with four previously developed models, the fit proved to be reasonable. Understanding of statistically significant variables in the developed model will enable designers to increase efficiency in terms of road operations and the development of traffic accident prevention policies in accordance with road design features.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.5
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• pp.49-59
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• 2017

In this study, We analyzed the characteristics of carsharing use and revealed the environmental factors influencing carsharing use using the records of carsharing had been operated in Incheon during 2016. The records show a higher ratio of male users, a big portion of 20s and 30s, and ascending trends in the use of elderly people and short distances compared to the past. We analyzed the relationship between carsharing use and neighborhood environmental factors using the negative binomial regression model. It was found that carsharing was more active in areas where have many public transportation users and higher portion of residential buildings. Therefore, it was concluded that these areas can be suitable candidates for placing new carsharing rental sites to expect more active carsharing use.

• Journal of Korean Society of Transportation
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• v.33 no.1
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• pp.81-89
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• 2015

Crashes that occur at tollgates have different characteristics compared to those of the mainline on expressways in terms of crash cause, crash type, and vehicle type. Due to this fact, the safety performance function (SPF) focused on the expressway tollgates, apart from the mainline, should be developed. The aim of this study is, therefore, to identify the influential factors and develope a SPF for crashes at tollgates. Firstly, we established independent variables affecting crashes at tollgates through literature review and descriptive statistical analysis. Based on these variables, two negative binomial regression models with different form of independent variables were developed and goodness-of-fits of each model were compared. According to the results, the number of crashes increases i) as AADT, Hi-pass rate, and heavy vehicle rate increase, ii) as average lane width decreases, iii) on the mainline tollgate type. The safety performance function developed in this study could be applied to select hot-spots for expressway tollgates.

• International Journal of Highway Engineering
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• v.12 no.2
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• pp.43-49
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• 2010

This study deals with the traffic accident of the Cheongju arterial link sections. The purpose of the study is to develop the traffic accident model. In pursuing the above, this study gives particular attentions to developing the ZAM(zero-altered model) model using the accident data of arterial roads devided by 322 small link sections. The main results analyzed by ZIP(zero inflated Poisson model) and ZINB(zero inflated negative binomial model) which are the methods of ZAM, are as follows. First, the evaluation of various developed models by the Vuong statistic and t statistic for overdispersion parameter ${\alpha}$ shows that ZINB is analyzed to be optimal among Poisson, NB, ZIP(zero-inflated Poisson) and ZINB regression models. Second, ZINB is evaluated to be statistically significant in view of t, ${\rho}$ and ${\rho}^2$ (0.63) values compared to other models. Finally, the accident factors of ZINB models are developed to be the traffic volume(ADT), number of entry/exit and length of median. The traffic volume(ADT) and the number of entry/exit are evaluated to be the '+' factors and the length of median to be '-' factor of the accident.