This paper uses Gaussian interval type-2 fuzzy se theory on historical traffic volume data processing to obtain a 24-hour prediction of traffic volume with high precision. A K-means clustering method is used in this p...This paper uses Gaussian interval type-2 fuzzy se theory on historical traffic volume data processing to obtain a 24-hour prediction of traffic volume with high precision. A K-means clustering method is used in this paper to get 5 minutes traffic volume variation as input data for the Gaussian interval type-2 fuzzy sets which can reflect the distribution of historical traffic volume in one statistical period. Moreover, the cluster with the largest collection of data obtained by K-means clustering method is calculated to get the key parameters of type-2 fuzzy sets, mean and standard deviation of the Gaussian membership function.Using the range of data as the input of Gaussian interval type-2 fuzzy sets leads to the range of traffic volume forecasting output with the ability of describing the possible range of the traffic volume as well as the traffic volume prediction data with high accuracy. The simulation results show that the average relative error is reduced to 8% based on the combined K-means Gaussian interval type-2 fuzzy sets forecasting method. The fluctuation range in terms of an upper and a lower forecasting traffic volume completely envelopes the actual traffic volume and reproduces the fluctuation range of traffic flow.展开更多
Fatigue has gradually become a serious issue for orthotropic steel deck used for long-span bridges. Two fatigue effects, namely number of stress cycles and equivalent stress amplitude, were introduced as investigated ...Fatigue has gradually become a serious issue for orthotropic steel deck used for long-span bridges. Two fatigue effects, namely number of stress cycles and equivalent stress amplitude, were introduced as investigated parameters in this paper. Investigation was focused on their relationships with traffic volume and ambient temperature by using 7-months fatigue monitoring data of an actual bridge. A fatigue analytical model considering temperature-induced changes in material property of asphalt pavement was established for verifying these relationships. The analysis results revealed that the number of stress cycles and equivalent stress amplitude showed a linear correlation with the traffic volume and ambient temperature, respectively, and that the rib-to-deck welded joint was much more sensitive to the traffic volume and ambient temperature than the rib-to-rib welded joint. The applicability of the code-recommended model for fatigue vehicle loading was also discussed, which revealed that the deterministic vehicle loading model requires improvement to account for significant randomness of the actual traffic conditions.展开更多
This article presents a comprehensive framework for determining the location of road weather information system （RWIS） stations over a regional road network. In the proposed methodology, the region is divided into a...This article presents a comprehensive framework for determining the location of road weather information system （RWIS） stations over a regional road network. In the proposed methodology, the region is divided into a grid of equal-sized zones which are considered as the minimum spatial unit for allocating a candidate set of RWIS stations. These zones are ranked according to a set of pre-specified criteria that reflect the needs for, and potential benefits from, real-time RWIS, including road surface temperature variability, precipitation, network traffic, and collision patterns. A case study based on the existing RWIS network in the province of Ontario was conducted to illustrate the major features of the proposed method and evaluate the implications of alternative loca- tion selection criteria. The findings of the study suggest that it is feasible to develop a systematic process for locating RWIS stations using an integrated location criterion to capture multiple factors being considered in prac- tice. The study has also revealed the need to establish quantitative models for estimating the benefit of real-time information from RWIS stations, which is the foundation of a cost-benefit-based RWIS location optimization model.展开更多
基金supported by the National Key Research and Development Program of China(2018YFB1201500)
文摘This paper uses Gaussian interval type-2 fuzzy se theory on historical traffic volume data processing to obtain a 24-hour prediction of traffic volume with high precision. A K-means clustering method is used in this paper to get 5 minutes traffic volume variation as input data for the Gaussian interval type-2 fuzzy sets which can reflect the distribution of historical traffic volume in one statistical period. Moreover, the cluster with the largest collection of data obtained by K-means clustering method is calculated to get the key parameters of type-2 fuzzy sets, mean and standard deviation of the Gaussian membership function.Using the range of data as the input of Gaussian interval type-2 fuzzy sets leads to the range of traffic volume forecasting output with the ability of describing the possible range of the traffic volume as well as the traffic volume prediction data with high accuracy. The simulation results show that the average relative error is reduced to 8% based on the combined K-means Gaussian interval type-2 fuzzy sets forecasting method. The fluctuation range in terms of an upper and a lower forecasting traffic volume completely envelopes the actual traffic volume and reproduces the fluctuation range of traffic flow.
基金supported by the National Natural Science Foundation of China(Grant No.51178100)the Key Program of Ministry of Transport(Grant No.2011318223190)+3 种基金the Project of the Priority Academic Development Program of Jiangsu Higher Education Institutions(Grant No.1105007001)the Teaching and Research Foundation for Excellent Young Teacher of Southeast University(Grant No.3205001205)the Graduate Scientific Innovation Research Foundation of Jiangsu Province(Grant No.CXZZ-0162)the Scientific Research Foundation of Graduate School of Southeast University(Grant No.YBJJ1122)
文摘Fatigue has gradually become a serious issue for orthotropic steel deck used for long-span bridges. Two fatigue effects, namely number of stress cycles and equivalent stress amplitude, were introduced as investigated parameters in this paper. Investigation was focused on their relationships with traffic volume and ambient temperature by using 7-months fatigue monitoring data of an actual bridge. A fatigue analytical model considering temperature-induced changes in material property of asphalt pavement was established for verifying these relationships. The analysis results revealed that the number of stress cycles and equivalent stress amplitude showed a linear correlation with the traffic volume and ambient temperature, respectively, and that the rib-to-deck welded joint was much more sensitive to the traffic volume and ambient temperature than the rib-to-rib welded joint. The applicability of the code-recommended model for fatigue vehicle loading was also discussed, which revealed that the deterministic vehicle loading model requires improvement to account for significant randomness of the actual traffic conditions.
基金funded by the Aurora Programfunded by National Sciences and Engineering Research Council of Canada (NSERC)Ontario Ministry of Transportation (MTO)
文摘This article presents a comprehensive framework for determining the location of road weather information system （RWIS） stations over a regional road network. In the proposed methodology, the region is divided into a grid of equal-sized zones which are considered as the minimum spatial unit for allocating a candidate set of RWIS stations. These zones are ranked according to a set of pre-specified criteria that reflect the needs for, and potential benefits from, real-time RWIS, including road surface temperature variability, precipitation, network traffic, and collision patterns. A case study based on the existing RWIS network in the province of Ontario was conducted to illustrate the major features of the proposed method and evaluate the implications of alternative loca- tion selection criteria. The findings of the study suggest that it is feasible to develop a systematic process for locating RWIS stations using an integrated location criterion to capture multiple factors being considered in prac- tice. The study has also revealed the need to establish quantitative models for estimating the benefit of real-time information from RWIS stations, which is the foundation of a cost-benefit-based RWIS location optimization model.
