The objective of this study is to identify the influencing factors of crash rates from the perspective of access management techniques in urban areas. The target areas are located in the Las Vegas Metropolitan area, and 19 arterials are selected. In order to address the interdependency between crash rates and travel speeds, and left-censored issue, a tobit model with endogenous variable is presented. The structure of the tobit model addresses the left-censored issue for the segments meanwhile the endogeneity issue between crash rates and travel speeds is explained. The results indicate that there is a strong interdependency between crash rates and travel speeds. The segment length, driveway density, median opening density, posted speed limit and AADT per lane are statistically significant factors that influence crash rates on segments, moreover, crash rates are significantly influenced by two-directional median opening density.
The Travelling Salesman Problem (TSP) is one of the most studied combinatorial optimization problem which is significant in many practical applications in transportation problems. The TSP problem is NP-hard problem and requires large computation power to be solved by the exact algorithms. In the past few years, fast development of general-purpose Graphics Processing Units (GPUs) has brought huge improvement in decreasing the applications’ execution time. In this paper, we implement 2-opt and 3-opt local search operators for solving the TSP on the GPU using CUDA. The novelty presented in this paper is a new parallel iterated local search approach with 2-opt and 3-opt operators for symmetric TSP, optimized for the execution on GPUs. With our implementation large TSP problems (up to 85,900 cities) can be solved using the GPU. We will show that our GPU implementation can be up to 20x faster without losing quality for all TSPlib problems as well as for our CRO TSP problem.
The contribution deals with the customers’ claims on provided services during train delay in personal railway transport. There is comparison between the situation in the Czech Republic (Brno main station) and Austria (Wien Westbahnhof) in the contribution. Development of the compensation policy cannot be based only on customer requirements. If the railway company focuses on providing compensation for delays, it must follow its economic balance. However, as the passengers' opinion survey showed, the negative impact of delays can be reduced by providing adequate information to passengers. Based on the passengers' opinion survey, it is necessary to consider the Regulation 1371/2007/ES as the minimum of the possible and on the basis of this reasoning to compile a compensation policy. The costs associated with compensation for the delay should be divided according to the causes of the delay among the individual culprits, so that railway undertakings bear the responsibility even for delays arising from reasons that are beyond the control of the railway undertaking itself.
The study determines the correlation between the application of advanced models and methods of inventory optimisation in the supply chain in relation to the satisfaction of employees who are responsible for managing the inventory optimisation processes. The previous studies confirm that the optimisation of inventory management in the supply chain insures competitive advantages on the market. There is space for further research of impact of the achieved inventory optimisation in the supply chain on the change of the employees’ satisfaction. The paper establishes the interrelation of the interdependence of the achieved inventory optimisations on the satisfaction of the employees and the related synergy effects of acquiring added value of the companies on the market oriented to the satisfaction of the buyers and service users. The research has defined new knowledge in interdependence of inventory management optimisation on the change of indicators of employees’ satisfaction. Based on the performed research an assumption has been created for the design of an application package (so-called XaaS-based services) for the management of interaction processes of inventory optimization in the supply chain, satisfaction of service users and employees.
The wrong behavior of the road traffic participants is a permanently discussed issue in many countries with advanced road transport. Such behavior doesn’t always result in traffic accident, but only in restriction or danger of the culprit or other participants. For monitoring the behavior problems we can for example use the video-analysis of the conflict situations.
The methodology of the conflict situations monitoring with the video-apparatus application is described in the paper presented. There are also results of the conflict situations analysis on the selected roundabouts in the Czech Republic.
The paper refers to suitability of the conflict situations video-analysis application not only for monitoring the wrong behavior of drivers and other participants of road traffic, but also for monitoring the inappropriately designed building elements (this hypothesis is confirmed by results of research, which are shown this article).
There is need for better understanding of how mobility management interventions work and how they affect the individuals’ modal choice decisions, as well as need for robust evaluation techniques allowing any behavioural changes to be observed. Changing individual’s behaviour is not a one-step process and any evaluation methodology should account for this. A new standardized expert evaluation resource MaxSUMO takes this step-wise process into account. MaxSUMO is based on a new theoretical behavioural change model MaxSEM which measures individuals’ stage positions (their susceptibility to change behaviour) and stage movement (progression towards actual behavioural change). This paper illustrates the use of MaxSUMO by the evaluation of the mobility campaign “I keep moving, even without my car” undertaken by the City of Ghent.
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