Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "transport congestion" wg kryterium: Temat


Wyświetlanie 1-4 z 4
Tytuł:
Modelling the public transport capacity constraints’ impact on passenger path choices in transit assignment models
Autorzy:
Drabicki, A.
Kucharski, R.
Szarata, A.
Powiązania:
https://bibliotekanauki.pl/articles/223577.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
public transport
congestion public transport
passenger congestion
public transport capacity
overcrowding
crowding discomfort
path choice
transport publiczny
przeciążenie transportu publicznego
możliwości przewozu pasażerów
Opis:
The objective of this paper is to discuss the replication of passenger congestion (overcrowding) effects on output path choices in public transport assignment models. Based on a comprehensive literature review, the impact of passenger overcrowding effects was summarised in 3 main categories: the inclusion of physical capacity constraints (limits); the feedback effect between transport demand and supply performance; and the feedback effect on travel cost (discomfort penalty). Further on, sample case studies are presented, which prove that the inclusion of capacity constraints might significantly influence the assignment output and overall results in public transport projects’ assessment – yet most state-of-the-practice assignment models would either miss or neglect these overcrowding-induced phenomena. In a classical 4-step demand model, their impact on passengers’ travelling strategies is often limited to path (route) choice stage, while in reality they also have far-reaching implications for modal choices, temporal choices and long-term demand adaptation processes. This notion has been investigated in numerous research works, leading to different assignment approaches to account for impact of public transport capacity constraints – a simplified, implicit approach (implemented in macroscopic-based models, e.g. PTV VISUM), and a more complex, explicit approach (incorporated in mesoscopic-based models, e.g. BusMezzo). In the simulation part of this paper, sample tests performed on a small-scale network aim to provide a general comparison between these two approaches and arising differences in the assignment output. The implicit approach reveals some differences in assignment output once network capacity constraints are accounted for – though in a simplified manner, and producing somewhat ambiguous output (e.g. in higher congestion scenarios). The explicit approach provides a more accurate representation of overcrowding-induced phenomena - especially the evolving demand-supply interactions in the event of arising congestion in the public transport network. Further studies should involve tests on a city-scale, multimodal transport model, as well as empirical model validation, in order to fully assess the effectiveness of these distinct assignment approaches.
Źródło:
Archives of Transport; 2017, 43, 3; 7-28
0866-9546
2300-8830
Pojawia się w:
Archives of Transport
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Forecasting travel time reliability in urban road transport
Autorzy:
Juhasz, M.
Matrai, T.
Koren, C.
Powiązania:
https://bibliotekanauki.pl/articles/223490.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
travel-time reliability
forecasting
urban road transport
appraisal
congestion
niezawodność czasu podróży
prognozowanie
transport drogowy
transport miejski
ocena
kongestia
Opis:
Assessment of travel time reliability as a fundamental factor in travel behaviour has become a very important aspect in both transport modelling and economic appraisal. Improved reliability could provide a significant economic benefit if it is adequately calculated in cost-benefit analyses for which the theoretical background has already been set. However, methods to forecast travel time reliability as well as travel behaviour models including its effects are rather scarce and there is a need for development in this field. Another important aspect could be the influencing factor of reliability in travel demand management and related policy-making. Therefore, this paper intends to further analyse reliability focusing exclusively on urban road transport based on automatic measurements of journey times and traffic volumes from a dataset of the city of Budapest. The main finding and the novelty of the study is a model which can forecast the standard deviation of travel times based on the volume-capacity ratio and the free-flow travel time. The paper also provides a real-life numerical experiment in which the proposed model has been compared with other, existing ones. It proves that besides existing mean-delay-based models, travel time reliability can be forecasted based on the volume-capacity ratio with an adequate accuracy.
Źródło:
Archives of Transport; 2017, 43, 3; 53-67
0866-9546
2300-8830
Pojawia się w:
Archives of Transport
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of the influence of expressway emergencies on transmission speeds and travel delays
Autorzy:
Shi, Xianfu
Liu, Xingliang
Li, Menghui
Liu, Tangzhi
Powiązania:
https://bibliotekanauki.pl/articles/2173933.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
expressway
congestion
propagation
travel time delay
logistic velocity
droga ekspresowa
kongestia transportowa
transport drogowy
prędkość logistyczna
Opis:
Expressway emergencies tend to cause traffic congestion, and understanding the travel time delays of on-road vehicles under different combinations of event scenarios and road traffic conditions is valuable for guiding the accurate emergency dispatch services. Most existing studies used methods that combine the Lighthill-Whitham-Richards (LWR) theory and basic traffic diagrams to solve this problem, but the discrete traffic flow characteristics caused by the presence of heavy vehicles have not been considered, thus affecting the applicability of those results to road traffic characteristics in China. Moreover, there is a lack of systematic research on multiple combinations of unexpected event scenarios and traffic conditions, and the guidance value of the previously obtained results is limited. In order to improve the applicability of the prediction model and accurately predict the severity of emergencies, based on a logistic model that is applicable to emergencies, a velocity–density model is constructed to describe discrete traffic flow characteristics. Based on LWR theory, the internal driving force of expressway traffic state evolution under emergency conditions is explored. Combined with real-time traffic flow data, the parameters of the logistic model are calibrated, and a logistic velocity-density model is constructed using a goodness-of-fit test and a marching method, including the free-flow velocity, turning density and heavy vehicle mixing ratio. Thus, the problem that existing models lack applicability to road traffic characteristics in China is solved. Travel time delay is associated with the impact range of an emergency, and it is an effective index for evaluating the severity of emergency incidents. Thus, the travel time delays under different scenarios, different numbers of blocked lanes and different orthogonal combinations of approximate saturation conditions are explored, and the impacts of lane blockage on emergency incidents and travel time delays are obtained. The conclusions show that the presented logistic velocity-density model constructed based on discrete traffic flow characteristics can properly quantify the impact of the presence of heavy vehicles. Additionally, the results can provide theoretical support for handling emergencies and emergency rescues.
Źródło:
Archives of Transport; 2022, 63, 3; 7--21
0866-9546
2300-8830
Pojawia się w:
Archives of Transport
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comprehensive service quality evaluation of public transit based on extension cloud model
Autorzy:
Hu, Xinghua
Chen, Xinghui
Zhao, Jiahao
Yu, Kun
Long, Bing
Dai, Gao
Powiązania:
https://bibliotekanauki.pl/articles/2173929.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
traffic engineering
public transit
urban traffic congestion
service quality
optimization
sustainable development
inżynieria ruchu
transport publiczny
zatory komunikacyjne
ocena jakości usług
optymalizacja
zrównoważony rozwój
Opis:
Prioritizing the development of public transit and enhancing its attractiveness is an important way to solve the problem of urban traffic congestion and achieve sustainable development. To improve the service quality and overall operational efficiency of urban public transit, an evaluation index system related to the comprehensive experience of passengers, service supply quality of public transit enterprises, and supervision of management departments was introduced from both the demand and the supply of public transit travel services. Based on the data distribution characteristics of the boxplot in statistics, the evaluation level and corresponding value range of each index were determined, and the comprehensive weight of the index was determined using the linear weighting method combining the analytic hierarchy process and the entropy weight method, so as to reduce the influence of single weighting method on the evaluation results of comprehensive service quality of public transit. An evaluation method of public transit comprehensive service quality based on the extension cloud model was established. The evaluation results of the model were obtained by calculating the cloud affiliation and comprehensive certainty, and a reliability factor was used to test the evaluation results, which solved the problem of randomness and fuzziness in the process of comprehensive service quality evaluation of public transportation and made the evaluation results closer to the reality. Finally, the established comprehensive evaluation model was applied to a city for example analysis, and the corresponding evaluation level was obtained as good. The value of the reliability factor in the model was less than 0.01, indicating that the model has good applicability and a certain application value for the comprehensive service quality evaluation of public transit. The evaluation method fully considered a variety of evaluation indicators, specified the evaluation level of comprehensive service quality of public transit, and the evaluation results provide a theoretical basis for public transport enterprise to make targeted improvement measures.
Źródło:
Archives of Transport; 2022, 61, 1; 103--115
0866-9546
2300-8830
Pojawia się w:
Archives of Transport
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-4 z 4

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies