As a significant role for traffic management, city planning, road monitoring, GPS navigation and map updating, the technology of road extraction from a remote sensing (RS) image has been a hot ...research topic in recent years. In this paper, after analyzing different road features and road models, the road extraction methods were classified into the classification-based methods, knowledge-based methods, mathematical morphology, active contour model, and dynamic programming. Firstly, the road features, road model, existing difficulties and interference factors for road extraction were analyzed. Secondly, the principle of road extraction, the advantages and disadvantages of various methods and research achievements were briefly highlighted. Then, the comparisons of the different road extraction algorithms were performed, including road features, test samples and shortcomings. Finally, the research results in recent years were summarized emphatically. It is obvious that only using one kind of road features is hard to get an excellent extraction effect. Hence, in order to get good results, the road extraction should combine multiple methods according to the real applications. In the future, how to realize the complete road extraction from a RS image is still an essential but challenging and important research topic.
► Network fundamental diagram is exploited to improve mobility in saturated traffic conditions. ► Based on a simple but efficient feedback control structure, gating is applied to control urban ...congestion. ► Application of the gating strategy leads to substantial improvements compared to the non-gating case.
Traffic signal control for urban road networks has been an area of intensive research efforts for several decades, and various algorithms and tools have been developed and implemented to increase the network traffic flow efficiency. Despite the continuous advances in the field of traffic control under saturated conditions, novel and promising developments of simple concepts in this area remains a significant objective, because some proposed approaches that are based on various meta-heuristic optimization algorithms can hardly be used in a real-time environment. To address this problem, the recently developed notion of network fundamental diagram for urban networks is exploited to improve mobility in saturated traffic conditions via application of gating measures, based on an appropriate simple feedback control structure. As a case study, the proposed methodology is applied to the urban network of Chania, Greece, using microscopic simulation. The results show that the total delay in the network decreases significantly and the mean speed increases accordingly.
•Incorporates a mixed-traffic bus alternative into a static traffic model with elastic demand.•Analyzes the distribution of welfare changes from an increase in road tolls under different ...assumptions.•A viable mixed-traffic bus alternative lets travelers with low values of time benefit from a toll increase.•Shows via counterexample that correlation of income with value of time does not imply road pricing is necessarily regressive.
Studies of road pricing in which the Value of Time (VOT) varies among travelers suggest that road pricing benefits travelers with high VOT and hurts travelers with low VOT. This happens because, when a toll reduces congestion, only high-VOT travelers value the time saved more than the money cost. This paper uses a static traffic model with elastic demands to examine how the presence of a mixed-traffic (one affected by congestion) bus alternative, which is cheaper but slower than driving, alters that logic. When “agents” (potential travelers) care only about the time and money costs of each alternative, it turns out that Pareto-improving toll increases are possible; and, absent a Pareto improvement, the “Full Cost of Travel” (inclusive of time and money costs) rises only inside an intermediate interval of VOT while falling for sufficiently high and low VOT. But when agents have heterogeneous “tastes” for each mode, the Full Cost of Travel falls for all agents with VOT higher than a certain level, and below that level the direction of change depends on an agent’s taste.
Roadway safety involves the three components of the roadway system: the people, the vehicle, and the roadway. When the design corresponds to what the driver hopes to find, the road is consistent; the ...most widely used methods to evaluate design consistency are based on analysis of the operating speed profile. When the roadway alignment does not violate driver expectations, the possibility of drivers making errors is reduced. The aim of this experimental study is to obtain widely valid formulas during the design phase to predict the speeds that will actually be found on rural roads. Studies have shown that the dominant influences on curve speed are local curvature and the speed environment pertaining to the road section. The environment speed is a driver's preferred speed of travel within a road section with relatively homogeneous alignment. For the purposes of this study, this speed was taken as the 85th percentile speed measured on a tangent or on the curve with the highest radius in a homogeneous road section.
Accurate and efficient extraction of road marking plays an important role in road transportation engineering, automotive vision, and automatic driving. In this article, we proposed a dense feature ...pyramid network (DFPN)-based deep learning model, by considering the particularity and complexity of road marking. The DFPN concatenated its shallow feature channels with deep feature channels so that the shallow feature maps with high resolution and abundant image details can utilize the deep features. Thus, the DFPN can learn hierarchical deep detailed features. The designed deep learning model was trained end to end for road marking instance extraction with mobile laser scanning (MLS) point clouds. Then, we introduced the focal loss function into the optimization of deep learning model in road marking segmentation part, to pay more attention to the hard-classified samples with a large extent of background. In the experiments, our method can achieve better results than state-of-the-art methods on instance segmentation of road markings, which illustrated the advantage of the proposed method.
This paper first presents a fuzzy expert system to identify and classify conventional two‐lane roads based on geometric characteristics. Both fuzzy and neuro‐fuzzy techniques have been used. Fuzzy ...logic has proved suitable to address this problem, since in this case, there is a variability of input information, and classical rules are not suitable to be used due to the uncertainty introduced by some combinations of the variables. Each road's geometric features were measured by sensors in an equipped vehicle, and are subsequently used to classify the roads according to their real condition. The conventional two‐lane roads used for this research are located in the Madrid Region, in Spain. This intelligent system may be used to update the road database regarding the assigned type to each conventional road, according to their present features and state. Also, a risk identification system has been developed to assess whether a vehicle is driving on a two‐lane road with an inappropriate speed, combining variables such as the former identification model, vehicle type, road longitudinal gradient, the angle covered by each horizontal curve, and the existence or not of an additional traffic lane. A fuzzy risk index is proposed for this approach. This fuzzy model may be useful to detect road sections where safety must be enhanced by revising the speed limit, since less safe situations may arise from travelling at unappropriated speeds.
Abstract
Mount Bromo in East Java is one of Indonesia’s priority tourist attractions. Safe, secure, orderly, and smooth traffic access is needed to support tourism. Safe roads can be an essential ...part of realizing this. This study aims to prioritize handling blackspots to discover safe roads. The research was conducted on three access roads to Mount Bromo from Probolinggo: Jalan Raya Sukapura, Jalan Raya Bromo, and Jalan Raya Lumbang. Analysis of the probability value of accidents, the impact value of the severity of accident victims, and the risk value of accidents are used to determine handling priorities. The results of the analysis obtained priority handling for Blackspot 1 by increasing the width of the road shoulder, Blackspot 2 by providing a crossing integrated with APILL, Blackspot 3 by completing street lighting and increasing lane width, Blackspot 4 by completing street lighting, and Blackspot 5 by increasing lane width. Prioritizing the handling of accident-prone locations in the road and environmental aspects can be done by reviewing the risk value of accidents for each road sub-component. A safe road will be realized at the Blackspot location.
Energy-management strategy plays a critical role in high fuel economy that modern hybrid electric vehicles can achieve, yet a lack of information about future driving conditions is one of the ...limitations of fulfilling the maximum fuel economy potential of hybrid vehicles. Today, with wider deployment of vehicle telematic technologies, prediction of future driving conditions, e.g., road grade, is becoming more realistic. This paper evaluates the potential gain in fuel economy if road grade information is integrated into the energy management of hybrid vehicles. Real-world road geometry information is utilized in power-management decisions by using both dynamic programming (DP) and a standard equivalent consumption minimization strategy (ECMS). At the same time, two baseline control strategies with no future information are developed and validated for comparison purposes. Simulation results show that road terrain preview enables fuel savings. The level of improvement depends on the cruising speed, control strategy, road profile, and the size of the battery.
Abstract
Start at present, investment in toll road construction is conventional investment in the form of investment within a certain period of time to obtain profits from the results of capital ...loans/financing obtained from toll revenues during toll road operation during the concession period by the BUJT. This means that BUJT has full authority over the implementation of road maintenance at the location of its concession. Hence toll road concessions have the obligation to maintain toll roads in accordance with minimum service standards using the company’s toll road revenues. Thus, each BUJT has their own maintenance policy. Therefore, the management of toll roads that are managed on a concession basis can lead to differences in road damage management programs in each BUJT concession. This research assesses the road maintenance program planning on BUJT toll road concession holders to see the effectiveness BUJT in carrying out road maintenance regarding of the fulfillment of SPM. The result shows that the majority of BUJT has regularly carried out efforts to improve road functions, however they have the inadequacy in conduct conditions surveys by using equipment according to the standards. with “Undertake routine efforts throughout the year to maintain road conditions” being the highest mean whereas “Perform visual assessment on foot” has the lowest mean value. Moreover, it can be determine that the road damage frequency data found is with the an “Adverse Opinion” audit findings result that is conducted by BPJT with the most frequent damage and receive an “Adverse Opinion” of an audit result was potholes with mean value of 2.100 and 2,200 that is followed by Guardrail damage with mean value of 2,1667 and 2,200. While the least frequent damage in the toll road was Drainage cross section with mean value of 2.533 and 2,700 and Rutting with mean value of 2.400 and 2,633 subsequently for damage frequency and Adverse Opinion frequency.
•Constructing and operating the roads have caused habitat quality reduction.•Road grade, operation duration, and length are the critical influencing factors.•InVEST models would be more appropriate ...to address the fragile ecology issues.•Establishing environmental protection zones may be a viable solution.•The study is helpful in designing environmentally-friendly projects.
Roadways vary in structural, geotechnical, locational, and operational properties, and synergies among these factors may present overwhelming challenges to understanding their full effects on the habitat quality (HQ). To explore the impact of dense roadway networks on an ecologically fragile region in the northwest of China, this study applied the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) to evaluate the HQ spatiotemporal distribution of the study area. Then, Generalised Estimating Equations (GEE) were formulated to examine the cumulative impact due to the operation of an increasing amount of roadways over the past two decades. According to the results, the influence of different road types on the HQ was apparent within the road-effect zone, and road grading reduction, road length and operation duration increase can harm the HQ within the road-effect zone. Overall, this study generates knowledge concerning the design and operation of environmentally-friendly roadways in ecologically fragile areas.
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