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1

Estimation of route speed parameters designed for electric buses

Czapla Zbigniew

Journal of civil engineering and transport

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2023

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Vol. 5, No. 3

9--20

EN

The paper presents a method for the estimation of speed parameters on urban bus routes designed for the use of electric buses. The considered bus route is divided into stopping and running sections. The bus stops are the stopping sections. The running sections connect two neighbouring bus stops. A bus equipped with the GPS receiver moves along the urban bus route at a variable speed. The GPS receiver records at a constant frequency location data that include current bus position and the measurement time. The location data enable the estimation of the time of varying speeds for the running sections and the stop time for the stopping sections. The speed parameters for the sections involve the specification of time periods assigned to the defined speed ranges. Measurement data were recorded on the selected bus route in off-pick and pick hours. The results obtained allow estimation of speed parameters for individual sections and by aggregation for the entire bus route considered. The speed parameters of the bus route correspond to the energy consumption of electric buses and can be applied to determine the properties of the urban bus routes on which electric buses are introduced.

PL

W artykule przedstawiono metodę określania parametrów szybkościowych na miejskich liniach autobusowych, na których wykorzystywane są autobusy elektryczne. Rozpatrywana linia autobusowa jest podzielona na odcinki postoju i jazdy. Przystanki autobusowe są odcinkami postoju. Odcinki jazdy łączą dwa sąsiednie przystanki autobusowe. Autobus wyposażony w odbiornik GPS przemieszcza się po linii autobusowej ze zmienną szybkością. Odbiornik GPS rejestruje ze stałą częstotliwością dane lokalizacyjne zawierające bieżącą pozycję i czas pomiaru. Dane lokalizacyjne umożliwiają określenie parametrów szybkościowych na odcinkach jazdy i czas postoju na odcinkach postoju. Parametry szybkościowe odcinków obejmują specyfikację okresów czasu przyporządkowanych do zdefiniowanych przedziałów szybkości. Dane pomiarowe zostały zarejestrowane na wybranej linii autobusowej poza godzinami szczytu i w godzinach szczytu. Otrzymane wyniki pozwalają na określenie parametrów szybkościowych dla pojedynczych odcinków oraz, przez agregację, dla całej rozpatrywanej linii autobusowej. Parametry szybkościowe linii autobusowej związane są ze zużyciem energii przez autobusy elektryczne i mogą być stosowane do wyznaczania właściwości miejskich linii autobusowych, na których wprowadzane są autobusy elektryczne.

2

Bicycle free-flow speed estimation based on GPS data – comparison of bike sharing system and Strava data

Pazdan Sylwia, Kiec Mariusz

Archives of Transport

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2023

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Vol. 68, iss. 4

77--90

EN

The increasing number of cyclists in cities around the world results in a greater focus on bicycle traffic. Next to traffic volume, the main characteristic of traffic used in road safety analysis, infrastructure planning, design, etc. is its speed. Bicycle speed is strongly affected by the type of bicycle facility, motor vehicle traffic parameters (volume, speed, share of heavy vehicles), trip motivation, weather conditions, etc., and therefore it is difficult to estimate. Traditionally, bicycle speed is determined directly using speed radar or indirectly, as a quotient of measurement base length and travel time calculated using a stopwatch or video technique. There are also researches where bicycle speed was esti mated based on GPS sources, mainly mobile apps. However, depending on the GPS source and the group of cyclists, bicycle speed gained from GPS data can be different from the speed of regular cyclists (due to different levels of experience or types of bicycle). In the paper, the relationships between bicycle speed obtained from empirical measurements and two different GPS sources, which were bike sharing system (Wavelo) and Strava app, were analysed. In total 18 research sites were selected different in terms of bicycle facility (bicycle path, shared pedestrian/bicycle path, contra flow lane) and element of road network (road segment, bicycle crossing with or without traffic signals). Two tailed test for two means was conducted to analyses the statistical significance of differences in bicycle speed estimated based on GPS data and empirical measurements using video technique. It showed that Wavelo and Strava speeds are by 17.4% lower are by 23.1% higher than the speeds of regular cyclists respectively. Two linear regression models describing relationships between bicycle speeds from empirical measurements and GPS data were developed. The results show that the variance of bicycle speed is almost 80% described by the variance of Wavelo speed and 60% described by the variance of Strava speed, which suggests that bicycle free-flow speed can be estimated based on GPS data either from bike share system or dedicated app.

3

Szacowanie natężenia ruchu rowerowego na podstawie danych z systemu rowerów miejskich

Pogodzińska S.

Transport Miejski i Regionalny

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2018

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nr 1

5--11

PL

W artykule przedstawiono metodę szacowania natężenia ruchu rowerowego na podstawie danych GPS z systemu rowerów miejskich. Badania wykonano na przykładzie miasta Krakowa, wykorzystując dane o dobowym natężeniu ruchu rowerowego z 5 pętli pomiaru automatycznego oraz dane GPS z systemu rowerów miejskich Wavelo. Na podstawie dwuczynnikowej analizy wariancji (ANOVA) oraz testu post-hoc Tukey’a określono wpływ czynników „lokalizacja” i „dzień tygodnia” na udział rowerów systemu miejskiego w całym potoku rowerzystów. Wykazano, że badany udział zmienia się statystycznie istotnie pomiędzy analizowanymi lokalizacjami. W przypadku udziału szacowanego w poszczególnych dniach tygodnia zmiana jest nieistotna. Wyznaczona zależność pomiędzy ogólnym natężeniem ruchu rowerowego i natężeniem ruchu rowerów systemu Wavelo charakteryzuje się wysokimi współczynnikami determinacji R2 (przekraczającymi wartość 0,90) oraz średnim błędem oszacowania nie większym od 11,5%. Wyniki przeprowadzonych badań wskazują na możliwość szacowania natężenia całości ruchu rowerowego na podstawie danych GPS z systemu rowerów miejskich. Praktyczne wdrożenie takiego sposobu szacowania natężenia ruchu rowerowego wymaga jednak przeprowadzenia pomiarów kontrolnych weryfikujących opracowane zależności wraz z określeniem wpływu lokalizacji przekroju pomiarowego.

EN

The article presents a method of estimation of bicycle traffic flow based on the GPS data from bike share system. Analyses have been made for the city of Krakow, using daily traffic data from 5 automatic counter loops and the GPS data from bike share system called Wavelo. Based on the two-factor analysis of variance (ANOVA) and the Tukey post-hoc test, the influence of „localization” and „day of the week” factors on the share of Wavelo bicycles in the entire bicycle flow was estimated. It has been proved that examined share is not significantly different between individual days of the week, but changes significantly between analyzed locations. Developed models are characterized by the high R2 coefficients (exceeding 0.90) and average error of estimation up to 11.5%. The results of the studies show that bicycle traffic flow can be estimated based on the GPS data provided by bike share system. However, it is necessary to carry out control measurements to verify developed models and their possibilities of application in bicycle traffic flow estimation in other locations.

4

Work-package 5 of the CERGOP-2/Environment: GPS data analysis and the definition of reference frames

Hefty J.

Reports on Geodesy

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2006

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z. 3/78

51-84

5

Final report presented by partner UNIPD for the period 01 April2003 - 31 July 2006

Caporali A., Facchinetti C., Bonafede L.

Reports on Geodesy

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2006

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z. 3/78

85-155

EN

Within the Project our group has been responsible of WP6, which addresses the stability of time series of coordinates of GPS stations used in the project. In addition we have supported WP1, WP4, WP7 and WP10.1, as scheduled. The time series we have analysed result from WP1 and WP5. We have combined normal equations from the EUREF network, and selected those stations which are relevant to the CERGOP 2 project. Likewise for Italian and Austrian stations we have stacked normal equations pertaining the national networks, and obtained time series which are useful to the science part of the Project. Finally we have addressed the normai equations of the CEGRN campaigns, up to the CEGRN 03 campaign, constructed time series and checked for their continuity. An in depth analysis of the time series was done for those sites which have been active with continuity for at least three years. We did this analysis for all the stations which met this requisite, including time series of a number of stations computed by the Austrian partner OLG. The analysis consisted in the identification, in the time and frequency domains of specific signatures, typically annual and semi annual, affecting the time series and can be of various origin, such as seasonal water flow or thermal dilatation of the antenna mount. After removal of the periodic signals, the power spectral density has been computed and the white and coloured components in the noise could be characterized. We report in most cases flicker phase noise at low frequencies and white noise at higher frequencies (>2 cycles/year), with a few exceptions in which the noise is white at all frequencies. A few stability problems are reported. In particular our own ASIA station was affected by mount instability in connection to a heavy snow storm in February 2006. This event was promptly noticed from the analysis and the mount problem could be solved. We have checked for local instabilities by looking at deviations of the estimated velocities from the expected pattern. We have verified that the stations contributing to the project have velocities agreeing with theoretical predictions. When this does not happen, then the station in most cases has a marginal tracking his tory, and we suspect that the discrepancies are attributable to a weak data set, more than true instability. The contribution to the Project includes, besides the data analysis part, two new permanent stations which were installed in Asiago and Rovigo as part of the Project, and regularly operated. Two doctoral stipendia have been awarded, and a Web page dedicated to our WP6 has been constructed, regularly maintained and linked to the Project's web page.

6

Crustal motion in Bulgaria based on geological and GPS data

Nakov R., Kotzev V., Burchfiel B. C., King R. W.

Reports on Geodesy

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2006

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z. 5/80

205--211