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Comparison of the Methodologies for Calculating Expressway Space Mean Speed Using Vehicular Trajectory Information from a Radar Detector
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Comparison of the Methodologies for Calculating Expressway Space Mean Speed Using Vehicular Trajectory Information from a Radar Detector
Han, Eum; Kim, Sang Beom; Rho, Jeong Hyun; Yun, Ilsoo;
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This study was initiated to evaluate the performance of methodologies to estimate the space mean speed(SMS) using the time mean speed(TMS) which was collected from the vehicle detection system(VDS) in expressways. To this end, the methodologies presented in prior studies were firstly summarized. It is very hard to achieve exact SMSs and TMSs due to mechanical and communication errors in the field. Thus, a microscopic traffic simulation model was utilized to evaluated the performance. As a result, the harmonic mean and volume-distance weighted harmonic mean were close to the SMS in the case in which the TMSs of individual vehicles were used. However, when the 30-second-interval aggregated TMS were used, the volume-distance weighted harmonic mean was outstanding. In this study, a radar detector was installed in the Joongbu expressway to collect the SMS. The trajectory of individual vehicles collected from the detector were used to calculate the SMS, which was compared with the estimates using other methodologies selected in this study. As a result, the volume-distance weighted mean was turned out to be close to the SMS. However, as the congestion becomes severe. the deviation between the two speed becomes bigger.
expressway;time mean speed;space mean speed;radar detector;
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레이더검지기의 차량궤적 정보기반의 고속도로 밀도산출방법에 관한 비교,김상구;한음;이환필;김해;윤일수;

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