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GPS pulse projection onto paths 

GPS pulse projection onto paths 

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Article
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Commercial bus speed is a key factor in the operation of public transport systems because it represents a direct measure of the quality of service provided to users and also considerably affects system costs. By commercial speed, we are referring to the average speed of buses over stretches, including all operational stops. Evaluating system perfor...

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Context 1
... important issue is the projection of the GPS locations onto the path definitions. These points were properly rectified using the methodology described previously (computing the orthogonal projection of the GPS points into the path line that is defined by the segmentation points). In Figure 2, we show the projection process in the following two interesting cases: a straight path and a 90-degree turn. In Figure 2, each pair ! ! denotes the position (in two-dimensional coordinates) that is instantly recorded by a GPS pulse i . The pair ( d ! , t ! ) corresponds to the new description of a GPS pulse i in which the position is translated into a distance measurement relative to the origin of the pulses’ associated route path. The computation of a representative speed for the Transantiago buses is a major challenge, mainly due to the amount of information and the degree of data disaggregation. To obtain reliable speed values, a crucial issue is the proper management, processing and estimation of the required inputs for the calculations (distance and lapses based on interpolations in time and ...
Context 2
... important issue is the projection of the GPS locations onto the path definitions. These points were properly rectified using the methodology described previously (computing the orthogonal projection of the GPS points into the path line that is defined by the segmentation points). In Figure 2, we show the projection process in the following two interesting cases: a straight path and a 90-degree turn. In Figure 2, each pair ! ! denotes the position (in two-dimensional coordinates) that is instantly recorded by a GPS pulse i . The pair ( d ! , t ! ) corresponds to the new description of a GPS pulse i in which the position is translated into a distance measurement relative to the origin of the pulses’ associated route path. The computation of a representative speed for the Transantiago buses is a major challenge, mainly due to the amount of information and the degree of data disaggregation. To obtain reliable speed values, a crucial issue is the proper management, processing and estimation of the required inputs for the calculations (distance and lapses based on interpolations in time and ...
Context 3
... important issue is the projection of the GPS locations onto the path definitions. These points were properly rectified using the methodology described previously (computing the orthogonal projection of the GPS points into the path line that is defined by the segmentation points). In Fig. 2, we show the projection process in the following two interesting cases: a straight path and a 90° turn. In Fig. ...
Context 4
... onto the path definitions. These points were properly rectified using the methodology described previously (computing the orthogonal projection of the GPS points into the path line that is defined by the segmentation points). In Fig. 2, we show the projection process in the following two interesting cases: a straight path and a 90° turn. In Fig. ...

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Citations

... Running speed and commercial speed represent two critical categories of operating speeds for vehicles traversing a route. The distinction between these speeds has been outlined in [44], with [45] contributing a model for calculating the commercial speed of buses along a route. Additionally, ref. [46] has identified the average speed for various transportation modes. ...
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... We propose a modeling framework that aims to provide a versatile MaaS system wherein users' trip requests are represented in terms of mode-agnostic mobility resources. In the proposed MaaS system, the average speed of travel modes is assumed to be known and representative of the commercial speed of each mode, defined as the average speed that incorporates service delays, e.g., waiting time, transfer time, and operational stop time into the average driving speed (Cortés et al., 2011). Commercial speed is a key factor in the operation of public transport systems since it represents a direct measure of the quality of service and also considerably affects system costs. ...
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... In public bus transportation networks, bus speed is considered to be a key performance indicator (KPI) that translates the level of efficacy and attractiveness of a bus network [7][8][9] Consequently, bus networks operators struggle daily to maintain high bus speed and are in need of reliable, complete, and flexible prospective methods to predict the performance (such as speed) of future bus lines. ...
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... A MaaS bundle is defined as a combination of service times across travel modes in the MaaS system. In this MaaS framework, the average speed of the travel modes is assumed to be known and representative of the "commercial speed" of each mode, defined as the average speed that incorporates service delays, e.g., waiting time, transfer time and operational stop time, into the average driving speed ( Cortés, Gibson, Gschwender, Munizaga, & Zúñiga, 2011 ). "Commercial speed" represents a direct measure of the quality of service and considerably affects system costs. ...
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... In general, waiting times can be estimated from the cyclist's speed profile. Different approaches have been taken to calculate the most likely speed profile [12][13][14][15] and to estimate the trend of motion. For example, Strauss and Miranda-Moreno (2017) = approximated the speed profile by averaging over three, four, and seven GPS points before estimating the cyclist's speed and time-delay at intersections, which is different from waiting time. ...
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... The speed of the buses was set to 12 km/h (considered the average speed of a standard bus on Labor Day), according to the Spanish association of managing companies for urban collective transport (Cortés et al., 2011). We are using a constant speed profile for the e Buses, the acceleration is therefore set to 0. As stated in Yu et al. (2016), the passenger mass only influences the bus energy consumption for speeds over 30 km/h. ...
... Moreover, in terms of the energy consumption, we are considering regenerative breaking when circulating downhill (see Eq. 13) with an average speed of 12 km/h (Cortés et al., 2011) and an overnight recharging strategy. ...
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... For example, smartcard systems, on-board bus units (AVLs 1 ), schedule, referential, and real time radio bus monitoring systems are a gold mine to manage the bus network, useful to understand how it works and what to act on to improve it. For example, the average trip travel time, the schedule, the amount of km per year, the average bus stop spacing, etc. can be considered as inputs that, when properly processed, help the creation of service quality indicators for bus networks [23,15,14]. ...
... Commercial speed, that is the speed of the bus felt by the passengers while they travel, is among the major indicators used by operators to evaluate the efficiency of bus lines and assess the state of health and quality / attractiveness of a bus network. This measure is computed using the total travel time over any section on which the indicator has to be computed, including boarding and alighting time at bus stops, traffic perturbation, and any time related factors that impact the travel time, hence the speed of buses as stated by [23,55,32,44,14,15]. Studies have been made on what to act on to both understand and control bus commercial speed fluctuations. ...
... They assessed this impact in the city of Helsinki, Finland. Traffic influence on buses travel time have also be reported to be prominent, as mentioned by Mazloumi [44] and Cortes [14]. However, the gathering of valuable traffic data seems to be a possible challenge. ...
Thesis
The so called data era we have entered in is accompanied by an explosion of data, both in variety and quantity. Public transportation is a data-intensive field, and related information systems are often supported by old technologies that struggle to keep up as the amount of data continually increases. This poses two problems. First, the massive data generated by the transportation network must be qualified and enriched with external data sources in order to be used for decision making. Second, in order to limit the number of tools and the complexity of maintenance, it is desirable to integrate data governance with decision support tools to allow non-expert operators to manipulate this data. Through four contributions leading to the proposal of a technical framework that integrates the past, present and future into a traditional information system containing a priori models, this thesis argues that the integration of various highly qualified datasets from the real world into a single spatio-temporal model provides a qualitative, efficient and low-cost mean of analysis, prediction and strategic decision support for bus networks while depreciating the use of data management systems in a non integrated multi-tool data management systems ?
... With travel speed, we can not only measure congestion but also derive the travel time and delay. The same holds true for the bus transit systems [1,2]. Predicting bus speeds in a timely and accurate manner contributes to maximizing the benefits of an intelligent public transit system [3]. ...
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