• 한국도로학회논문집
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• 제18권4호
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• pp.19-28
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• 2016

PURPOSES : Long-life asphalt pavements are used widely in developed countries. In order to be able to devise an effective maintenance strategy for such pavements, in this study, we evaluated the performance of the long-life asphalt pavements constructed along the national highways in South Korea. Further, an economic evaluation of the long-life asphalt pavements was performed based on a life-cycle cost analysis. We aimed to devise a model for evaluating the performance of long-life asphalt pavements using the national highway pavement management system (PMS) database as well as for analyzing the economic feasibility of such pavements, in order to promote their use in South Korea. METHODS : The maintenance history and pavement performance data were obtained from the national highway PMS database. The pavement performances for a total of 292 sections of 10 lanes (5 northbound lanes and 5 eastbound lanes) of national highways were used in this study. Models to predict the performances of hot mix asphalt (HMA) and long-life asphalt pavements under two distinct traffic conditions were developed using a simple regression method. Further, the economic feasibility of long-life asphalt pavements was evaluated using the Korea Pavement Management System (KoPMS). RESULTS : We developed service-life prediction models based on the traffic volume and the equivalent of single-axle load and found that long-life asphalt pavements have service lives 50% longer than those of HMA pavements. Further, the results of the economic analysis showed that long-life asphalt pavements are superior in terms of various economic indexes, including user cost, delay cost, total cost, and user benefits, even though their maintenance cost is higher than that of HMA pavements. A comparison of the economic feasibilities of the various groups showed that group A is superior to HMA pavements in all aspects except in terms of the maintenance criterion (crack 20% or higher) as per the NPV index. However, the long-life asphalt pavements in group B were superior in terms of the maintenance criterion (crack 25% or higher) regardless of the economic feasibility. CONCLUSIONS : The service life of long-life asphalt pavements was found to be approximately 50% longer than that of HMA pavements, regardless of the traffic volume characteristics. The economic feasibility of long-life asphalt pavements was evaluated based on the KoPMS. The results of the economic analysis were the following: long-life asphalt pavements are exceptional in terms of almost all factors, such as user cost, delay cost, total cost, and user benefit; however, the exception is the maintenance cost. Further, the economic feasibility of the long-life asphalt pavements in group B was found to be better than that of the HMA pavements (crack 25% or higher).

• 한국음향학회지
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• 제39권6호
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• pp.606-614
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• 2020

본 논문에서는 수중 주변소음 생성에 주요한 영향을 끼치는 선박 통행량 및 해양기상정보와 수중 주변소음간 영향성을 분석한다. 주변소음은 수중 소나 시스템의 탐지 성능에 큰 영향을 끼치는 중요한 환경 요소이다. 최근에 많은 연구가 진행 중인 인공지능 기술을 이용한 탐지성능 예측 등 자동화 시스템 구현을 위하여 이와 관련된 주요 데이터 확보 및 분석이 필요하다. 주변소음의 주요 발생원은 다양한 원인이 있는데, 연근해에서 운용되는 소나 시스템의 경우 탐지 성능에 있어서 선박 통행에 의한 소음 및 해양 기상에 의해 발생하는 소음의 영향을 크게 받는다. 따라서 본 논문에서는 대한민국 동해 연안에서 획득한 주변소음 측정 결과와 인근 선박 통행량 및 해양기상정보 공공데이터를 이용하여 각 데이터의 영향성을 분석하였다. 분석 결과 수중 주변 소음은 선박의 통행량의 변화에 따라 높은 연관성을 보였으며, 풍속과 파고, 강우 등 해양환경 요소에 있어서도 특정 주파수 대역에 영향성이 있음을 관찰하였다.

• 대한토목학회논문집
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• 제32권2D호
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• pp.137-145
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• 2012

경찰청 발표 자료에 따르면 2010년 우리나라에서 발생한 교통사고 건수는 226,878건으로 전체 교통사고 중 교차로가 차지하는 비중이 44.8%로 교차로 사고는 교통사고 중 많은 부분을 차지하고 있다. 이 중 신호교차로 교통사고에 대한 연구는 지속적으로 이루어지고 있는 반면에 비신호교차로에 대한 연구는 아직 부족한 실정이다. 본 연구는 환경적 요인으로 퍼지적 성격을 가진 교통량, 차로폭, 시거를 입력변수로 비신호교차로에서의 사고건수예측을 위한 ANFIS(Adaptive Neuro-Fuzzy Inference System) 모형을 구축하였다. 이렇게 구축된 모형의 예측력은 검증자료를 이용한 실측치와 추론치를 비교함으로써 평가되었다. 본 모형의 예측력은 결정계수인 $R^2$와 평균절대오차(MAE), 평균제곱근오차(MSE)를 통하여 적합성을 평가하였으며, 이들은 각각 평가 결과 0.9817, 0.4773, 0.3037로 나타나 모형의 설명력이 우수한 것으로 평가된다. 본 연구의 비신호 교차로 사고예측분석 연구결과는 비신호교차로의 안전 대책 수립 및 교통사고 개선사업을 위한 기초자료를 제공할 것으로 사료된다.

• 한국항해항만학회지
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• 제38권1호
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• pp.65-71
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• 2014

국내 경부고속도로와 남해고속도로는 부산항을 각각 남북방향과 동서방향으로 연계하며 20%이상의 중대형화물트럭 혼재율과 특정시간대 통행량이 집중되는 핵심 간선도로로 시간교통량계수(K-factor)에 대해 연구의 필요성을 깨닫게 되었다. 그리하여 본 연구에서는 경부고속도로와 남해고속도로의 기본구간에서 단기간동안 수집된 차량검지시스템(vehicle detection system, VDS)자료를 이용하여 고속도로의 K-factor와 K-factor추정치(estimate)사이의 상관분석을 통해서 고속도로의 K-factor추정모형 구축을 목적으로 연구하였다. 결과적으로 7일 VDS자료의 K-factor추정치(estimate)와 함께 파워(POW)모형이 K-factor를 추정에 높은 설명력과 신뢰성이 있음을 확인할 수 있었다.

• 한국측량학회지
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• 제19권3호
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• pp.211-217
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• 2001

춘천시는 여러 가지 자연재해 중 홍수로 인한 댐의 붕괴 시 상당한 피해를 입을 것으로 예상되는 지역이다. 그렇다면 피해를 최소로 하는 방법은 무엇이 있겠는가\ulcorner 많은 방법이 있겠지만 댐이 붕괴되기 전 대피하는 것이 가장 좋은 방법이 될 것이다. 그러면 몇 시간 전에 대피를 해야 하고 어떤 도구로 대피해야 인명의 피해를 최소로 할 수 있을 것인가\ulcorner 또한 어떤 방법으로 시간을 산정 할 수 있을 것인가\ulcorner 이 연구에서는 이러한 의문을 ARC/INFO 기반의 GIS 기능인 버퍼링, 중첩, 네트워크를 이용하여 춘천시 외곽으로 대피할 수 있는 6개의 노선을 선정하였고, 각 노선의 교통량을 계산하여 위험 분산을 위한 시간을 예측해 보았다.

• 한국대기환경학회지
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• 제14권6호
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• pp.607-620
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• 1998

The influence of transportation on air quality has been elevating in urban area. Air pollutants from automobiles cause primary and secondary air pollution, and need to be tightly controlled. In this study, the effect of automobile air pollutants on highway vicinity area was evaluated by the comparison of field measurement. and target was for modeling using CALINE3, NO2 was the target for this work. It was found that the concentration predicted by CALINE3 is overestimated at low wind speed and input data of wind speed requires correction. Based on the measured data, the wind speed was modified by effective wind speed equation [Ue=U+0.24·EXP(-pxU)], and there after the accuracy of CALINE3 calculation was improved neighborhood area of highway. It was also observed that weather conditions and traffic volume affect the concentration of air pollution. Finally, the NO2 effect of automobile air pollutants on the vicinity area of highway proved to be up to 400∼600m from the highway.

• 한국도로학회논문집
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• 제17권3호
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• pp.69-76
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• 2015

PURPOSES : Performance evaluation of four types of asphalt concrete overlays for deteriorated national highways. METHODS : Pavement distress surveys for crack rate and rut depth have been conducted annually using an automated pavement survey vehicle since 2007. Linear and non-linear performance prediction models of the asphalt concrete overlays were developed for 43 sections. The service life of the asphalt overlays was defined as the number of years after which a crack rate of 30% or rut depth of 15mm is observed. RESULTS : The service life of the asphalt overlays was estimated as 17.4 years on an average. In 90.7% of the sections, the service life of the overlays was 15 years or more which is 1.5 times the life of conventional asphalt concrete overlays used in national highways. The performance of the overlays was dependent on the type of asphalt mixture, traffic volume levels, and environmental conditions. CONCLUSIONS : The usage of stone mastic asphalt (SMA) and polymer-modified asphalt (PMA) for the overlays provided good resistance to cracking and rutting development. It is recommended that appropriate asphalt concrete overlays must be applied depending on the type of existing pavement distress.

• 한국도로학회논문집
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• 제16권5호
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• pp.99-108
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• 2014

PURPOSES : The travel times of expressway buses have been estimated using the travel time data between entrance tollgates and exit tollgates, which are produced by the Toll Collections System (TCS). However, the travel time data from TCS has a few critical problems. For example, the travel time data include the travel times of trucks as well as those of buses. Therefore, the travel time estimation of expressway buses using TCS data may be implicitly and explicitly incorrect. The goal of this study is to improve the accuracy of the expressway bus travel time estimation using DSRC-based travel time by identifying the appropriate analysis period of input data. METHODS : All expressway buses are equipped with the Hi-Pass transponders so that the travel times of only expressway buses can be extracted now using DSRC. Thus, this study analyzed the operational characteristics as well as travel time patterns of the expressway buses operating between Seoul and Dajeon. And then, this study determined the most appropriate analysis period of input data for the expressway bus travel time estimation model in order to improve the accuracy of the model. RESULTS : As a result of feasibility analysis according to the analysis period, overall MAPE values were found to be similar. However, the MAPE values of the cases using similar volume patterns outperformed other cases. CONCLUSIONS : The best input period was that of the case which uses the travel time pattern of the days whose total expressway traffic volumes are similar to that of one day before the day during which the travel times of expressway buses must be estimated.

• 한국도로학회논문집
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• 제14권6호
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• pp.131-138
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• 2012

PURPOSES : Two-lane highways have one lane in each direction, and lane changing and passing maneuvers take place in the opposing lane depending on the availability of passing sight distance. 2001 Korea Highway Capacity Manual (KHCM) is classified into two classes of two-lane highways (Type I, II), and average travel speed and time-delayed rate are used as measures of effectiveness (MOEs). However, since existing two-lane highways have both uninterrupted and interrupted traffic flow-system elements, a variety of free-flow speeds exhibits in two-lane highways. In addition, it is necessary to check if the linear-relationship between volumes and time-delayed rate is appropriate. Then, this study is to reestablish the relationship between average travel speed, time-delayed rate, and flow. METHODS : TWOPAS model was selected to conduct this study, and the free-flow speeds of passenger cars and the percentage of following vehicles observed in two-lane highways were applied to the model as the input. The revised relationships were developed from the computer simulation. RESULTS : In the revised average travel speed vs. flow relationship, the free-flow speed of 90km/h and 70km/h were added. It shows that the relationship between time delayed-rate and flow appeared to be appropriate with the log-function form and that there was no difference in time-delayed rate between the free flow speeds. In addition to revise the relationships, the speed prediction model and the time-delayed rate prediction model were also developed. CONCLUSIONS : The revised relationships between average travel speed, time-delayed rate, and flow would be useful in estimating the Level of Service(LOS) of a two-lane highway.

• 문화기술의 융합
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• 제8권6호
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• pp.861-866
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• 2022

서울시에서는 공유 자전거 시스템, "따릉이"를 2015년부터 도입, 운영하여, 교통량 감축과 대기오염 해소를 위해 노력하고 있다. 하지만 공유 자전거 시스템, "따릉이"의 운영전략 미훕으로 인해 많은 문제가 발생하고 있어 이를 해결하고자 다양한 연구들이 제시되고 있다. 이들 연구의 대다수는 수요와 공급의 불균형을 해결하고자 하는 전략적 "자전거 배치"에 집중되어 있으며 또한 이들 중 다수가 날씨나 계절과 같은 특징을 그룹화함으로써 수요를 예측하고 있다. 그리고 이전에는 이들 예측방법이 주로 시계열 분석을 기반으로 하고 있었으나 최근에는 딥러닝/머신러닝으로 수요를 예측하는 연구들이 속속 등장하고 있다. 본 논문에서는 기존에 제시된 다양한 특징들을 기반으로 하면서, 새로운 특징을 발견하고 선택된 특징들의 중요도를 비교, 이를 순서화함으로써, 보다 정확한 수요 예측이 가능함을 보인다. 그리하여, 우리는 기존의 딥러닝/머신러닝 및 시계열 분석을 그대로 사용하면서 비교적 정확한 결정계수를 획득하고 이를 이용해 개선된 수요예측이 가능하도록 한다.