Jolanta Żak

Models of traffic flow distribution for various scenarios of the development of proecological transport system

The paper is a result of a research work concerning the development of an environmentally friendly transport system Project EMITRANSYS. The publication contains the issues of shaping the transport system, where important factor due to the aspect of sustainable development is including the external costs in transport activity. This paper presents a mathematical model of the distribution of the traffic flow in the transport network. The paper presents selected aspects of the problem of multi-variant distribution of the traffic stream on the network transport for defined scenarios for the transport system development. Traffic distribution on the network has been made due to the criterion function – external cost connected with air pollution. The paper presents modal split of traffic ecological flow for chosen scenarios of the development domestic transport system.

Vehicle routing in an urban area: environmental and technological determinants

This paper discusses selected environmental and technological issues of routing freight vehicles in urban areas. The conditions of organizing distribution minimizing not only realization time but also the emission of harmful components of exhaust gases are described. Time-dependant traffic conditions characteristic for densely populated urban areas are defined and discussed according to ecological aspects. Theoretical information about CO2 emission in urban conditions are gathered and used to formulate the base of a mathematical model of a Time-Dependant Vehicle Routing Problem with emission criteria function, as a version of the Capacitated Vehicle Routing Problem. The model comprises selected characteristics of urban transport infrastructure such as distances, speed limits, zones, or the effect of rush hours. It allows considering different types of vehicles according to the task requirements and emission characteristics, and changing traffic conditions. The model is implemented onto a representation of a real transport network and solved for given data with two-step heuristics based on a modified A-star algorithm and genetic programming. Appropriate results, future research directions and other potential uses are presented and discussed.

EXHAUST EMISSION MEASUREMENTS IN THE DEVELOPMENT OF SUSTAINABLE ROAD TRANSPORT

Economic development of nations leads to a higher living comfort of the society. Rich societies want to move safely and independently and demand immediate availability of purchased goods or – in the case of Internet shopping – delivery in the shortest possible time. Such an approach facilitates a continuous growth in the number of road vehicles. At the current level of technology advancement, an increasing number of vehicles results in a growth of the consumption of fossil fuels, which entails increased exhaust emissions and that, in turn, has a negative impact on the health of the living organisms. Another negative consequence of an increased number of vehicles (increased road congestion) is the emission of noise. This problem is particularly significant in large agglomerations where people are surrounded by moving vehicles. This paper presents the extent of influence of the automotive industry on the natural environment and the extent of changes in vehicle design and organization of road infrastructure that were instituted to reduce the transport’s environmental burden. The further part of the paper presents a definition of the development of sustainable transport, its advantages and hurdles that we may encounter when modernizing a transport system. Subsequently in the paper, the measurements under actual vehicle operating conditions were described together with the possibilities of analysis of the research results and the advantages resulting from such an approach during the assessment of the impact of the automotive industry on the natural environment.

Some aspects of risk assessment in the logistics chain

The paper presents selected aspects of the evaluation of the effectiveness and risks of the logistics chain that supports the enterprise. It was assumed that the logistics chain includes all activities associated with the flow of materials from the sourcing of raw materials for sale to the ultimate purchaser of the product and the disposal of used products. It was found that the elements of the supply chain are usually unstable which generates difficulties in determining the appropriate level of the risk of the chain. The paper presents a formal record of risk and performance. There is proposed determination of the effectiveness of individual links of the logistics chain. The task of the logistics chain is to provide goods from producers to the final customers, thereby making available these goods in a place and time suited to the needs and expectations of customers. The movement of goods in the logistics chains is determined by the sequence of interrelated actions. In the logistics chains, many entities are involved to different extents. This determines the spatial distribution of different configuration of individual users of the whole logistics chain. In particular, example of a logistics chain of production company, stages of the procedures for quantitative risk analysis, the problems in the logistics chains, assessment of the risk of the task in the logistics chain, the concept of risk, effectiveness and risk in logistics chains are presented in the paper.

Decision making strategies for warehouse operations

The paper presents issues related to design and organization of warehouse processes. Draws attention to problems of modelling logistics facilities and processes occurring in them. Paper also points out the essence of correct operation of warehouses and associated with this risks for supply chain. Warehouse processes have been properly defined and divided into smaller components, like: phases of process, activities, sets of procedures, procedures or working movements. Paper presents various possible configurations of warehouse processes, which were named as warehouse strategies. Warehouse process strategy is a part of warehousing. It determines the sequence of warehouse operations. These operations are related to internal transport, cargo form transformation and cargo buffering. In paper it is noted that the warehouse strategy depends on the several technical and organizational factors and is associated with a certain probability. This probability can be estimated based on data analysis concerning logistics processes in the specified warehouse facility. As shown in case study, appropriate selection of warehouse strategies determines possibility of fulfilling customer order in time and costs that are acceptable for him.

The influence of road transport on emission of toxic substances in Poland against the EU countries

The paper is a result of research work carried out under the project EMITRANSYS for shaping ecological transport system. The paper presents selected aspects of emission and concentration of harmful compounds of exhaust gases generated by road transport. It also presents the share of harmful compounds emitted by road transport in comparison with the emission from other sectors of economy. Transport policy should encourage the usage of energyefficient and less environmentally damaging modes of transport and their efficient use. The paper analyses the emissions of selected pollutants and their estimated contribution to the total emissions of road transport. It also presents selected aspects of the identification of areas with the highest emissions of harmful compounds in Poland against the European Union. This analysis provides a basis to identify the instruments to prevent and reduce pollution arising from transport activities. In particular, variable emission of selected components of fumes according to the velocity of passenger vehicle. the measured values for NO2 concentration in the UE countries in 2011, the measured values for CO concentration in UE countries in 2011, the measured values for PM10 concentration in UE countries in 2011, the measured values for PM2.5 concentration in UE countries in 2011 are presented in the paper.

Simulation Models in Testing Reliability of Transport Process

Abstract The paper touches the problem of applying simulation models to assess the reliability of services in transport networks. Investigation of the transport processes in terms of their reliability is a complex decision-making task. The paper describes a method for assessing the reliability of transport process on the base of the criterion of minimizing the normalized lost time of vehicles. The time is wasted in a result of conflict situations occurring in the transport network during the transport process. The study includes stochastic distributions of system input. It enables studying the quality parameters of the transport network equipment, including service providers working under different workload and all kinds of disturbances. The method uses simulation models. Simulation studies were performed with Java Modelling Tools.

The Influence Of The External Costs Of Modal Split In The Transport Network, With Particular Reference To Rail Transport

Vehicles have an impact on environmental pollution through emissions. Thus, they generate different carbon footprints, or emit different amounts of carbon dioxide into the atmosphere. This article attempts to determine the effects of carbon dioxide on the distribution of the traffic stream in the selected part of the transport network. For the analysis the Warsaw–Krakow route was chosen. The movement between these two cities can be performed with different modes of transport. The distribution of the passenger streams was conducted for three variants of the three sub-criteria: minimum average costs, minimum marginal costs and the costs of environmental pollution. The unitary cost of carbon dioxide emission was determined using a CO₂ Calculator. The selection of the variant of the passenger stream distribution was carried out using a multi-criteria evaluation method called MAJA.

The Role Of Railway Transport In Designing A Proecological Transport System

This paper is prepared as a part of the scientific project “Proecological transport system designing” (EMITRANSYS). It presents the selected aspects and roles of railway transport in realization of the tasks set out by the national transport system. Particular attention is paid to the ecological aspects of railway transport, especially to the emission of pollutants in comparison to road transport. The ecological aspects are crucial for a systemic approach to the designing of transport and are important in developing a sustainable economy. One of the criteria for designing a large scale transport system is the external cost of environmental degradation. Two partial criteria considering external costs related to harmful emissions resulting from cargo and passenger streams distribution onto a network are discussed in the paper. These criteria are implemented into the PTV Visum environment for simulation experiments.

Technical and environmental limitations of pro-ecological transport system designing

Transport is one of the most environmentally destructive branches of economy. It contributes to environmental degradation and influences negatively on human live. It should therefore seek to reduce the negative impact on the environment. The paper presents many aspects of development of the national transport system. In article characterized technical constraints and environmental issues, which are applicable to the designing of pro-ecological transport system. Presented in it also indicators of the proposed design solution quality. In shaping the pro-ecological system the special role plays environmental restrictions, because they mainly determine the quality of solutions in terms of minimizing the negative impact of transport on the environment. Technical factors are equally important, because they allow, among others, reducing the external costs of congestions and allow on the creation of transport tasks on the appropriate level. In particularly, EU requirements for sustainable development of the transport system, the components of the external costs arising from the sphere of transport, indicators and ecological limitations in designing of pro-ecological transport system, ecological limitations, technical limitations, indicators for assessing pro-ecological transport system are presented in the paper.