rss_2.0Transport and Telecommunication Journal FeedSciendo RSS Feed for Transport and Telecommunication Journal and Telecommunication Journal 's Cover Digital or Sustainable Small and Medium-Sized Port? Sustainable Port Blueprint in the Baltic Sea Region Based on Port Benchmarking<abstract> <title style='display:none'>Abstract</title> <p>Small and medium-sized ports (SMSPs) in the Baltic Sea Region (BSR) are caught in a dilemma of less financial support by the European funding programmes due to their peripheral position in the TEN-T Core Network. Most of the BSR ports belong to the TEN-T Comprehensive Network, which is rationally less important in the topical financial, infrastructural and policy discourses. Despite this, BSR ports are of a colossal importance for the regional economic development serving as gateways for the individual regions and drivers of socio-economic and environmental transition. In addition, ports are essential in pursuing new innovation avenues. The environmental targets published by the European Commission for maritime sector in 2030 and 2050 are applicable for SMSPs as well, creating further obstacles and future challenges on the one hand, but opening new horizons to grow and innovate on the other one. A successful environmental and digital transformation going hand in hand in SMSPs enable sustainable boost of sustainable development. Thus, as a first step, the assessment of sustainable readiness in SMSPs is incumbent in order to implement tailor-made solutions on individual basis, by ensuring efficient usage of available resources and capabilities. In line with the Connect2SmallPorts project, part-financed by the INTERREG South Baltic Programme, 38 SMSPs in the BSR were approached to mapping their digital readiness according to the methodology of the Digital Readiness Index for Ports (DRIP), published within the project in 2020. Building upon this, this paper introduces the idea of digital and environmental twinning to conclude on sustainable development potentials in SMSPs with an adaptation of the DRIP score. Hence, the research contributes to the sustainable port concept and illustrates the positioning of SMSPs in the progress of sustainable development.</p> </abstract>ARTICLE2021-06-22T00:00:00.000+00:00Analysis and Prediction of Vehicles Speed in Free-Flow Traffic<abstract> <title style='display:none'>Abstract</title> <p>Speed is a crucial factor in the frequency and severity of road accidents. Light and heavy vehicles speed in free-flow traffic at six locations on Poland’s national road network was analyzed. The results were used to formulate two models predicting the mean speed in free-flow traffic for both light and heavy vehicles. The first one is a multiple linear regression model, the second is based on an artificial neural network with a radial type of neuron function. A set of the following input parameters is used: average hourly traffic, the percentage of vehicles in free-flow traffic, geometric parameters of the road section (lane and hard shoulder width), type of day and time (hour). The ANN model was found to be more effective for predicting the mean free-flow speed of vehicles. Assuming a 5% acceptable error of indication, the ANN model predicted the mean free-flow speed correctly in 84% of cases for light and 89% for heavy vehicles.</p> </abstract>ARTICLE2021-06-22T00:00:00.000+00:00Travel Demand Estimation in Urban Road Networks as Inverse Traffic Assignment Problem<abstract> <title style='display:none'>Abstract</title> <p>Nowadays, traffic engineers employ a variety of intelligent tools for decision support in the field of transportation planning and management. However, not a one available tool is useful without precise travel demand information which is actually the key input data in simulation models used for traffic prediction in urban road areas. Thus, it is no wonder that the problem of estimation of travel demand values between intersections in a road network is a challenge of high urgency. The present paper is devoted to this urgent problem and investigates its properties from computational and mathematical perspectives. We rigorously define the travel demand estimation problem as directly inverse to traffic assignment in a form of a bi-level optimization program avoiding usage of any pre-given (a priori) information on trips. The computational study of the obtained optimization program demonstrates that generally it has no clear descent direction, while the mathematical study advances our understanding on rigor existence and uniqueness conditions of its solution. We prove that once a traffic engineer recognizes the travel demand locations, then their values in the road network can be found uniquely. On the contrary, we discover a non-continuous dependence between the travel demand locations and absolute difference of observed and modeled traffic values. Therefore, the results of the present paper reveal that the actual problem to be solved when dealing with travel demand estimation is the problem of recognition of travel demand locations. The obtained findings contribute in the theory of travel demand estimation and give fresh managerial insights for traffic engineers.</p> </abstract>ARTICLE2021-06-22T00:00:00.000+00:00Time and Space Discretization in the Digital Twin of the Airport Transport Network<abstract> <title style='display:none'>Abstract</title> <p>The paper describes the concept of a Digital Twin (DT) creation, which could be used as part of a centralized ground traffic control system in the airport’s apron area. The work is focused on the automatic control systems expected in the future, which will completely replace the ground traffic controllers that solve the centralized control’s tasks in our days. It is assumed that the developed DT can be used both at the stage of training the control system and at the stage of its use. A special feature of the proposed DT concept is the clearly formulated principles of the observed process’ time discretization and the space in which the movement of ground vehicles and aircraft occurs. The experimental verification of the developed concept was carried out using a special simulation model designed to generate data streams on the airport’s transport network’s traffic participants’ location.</p> </abstract>ARTICLE2021-06-22T00:00:00.000+00:00Data Sources Analysis for Sustainable Trip Planner Development for Riga City<abstract> <title style='display:none'>Abstract</title> <p>In today’s daily traveller world, not only the time and money became important, but climate change and pandemic raised the importance of safety and sustainability of future trip plans. In order to provide such a wide coverage for a variety of important information, a sustainable trip planner needs to receive a lot of data from a variety of differentiated data sources. Provided review of related works shows that a lot of started activities in this aspects gives all of us promises and hope that available Big Data sources will be wisely used in order to bring added value not only to individual travellers, but also society, the transportation services will become better structured and information will be easily available for smart and safe decision making, that gradually will increase life quality.</p> <p>The study’s main goal is analysis of open data sources for the trip planner development. Authors analysed availability of data for Riga transport system and data usage for sustainable trip planner.</p> </abstract>ARTICLE2021-06-22T00:00:00.000+00:00Trajectory Planning of Autonomous Vehicle in Freeway Driving<abstract> <title style='display:none'>Abstract</title> <p>This paper describes trajectory planning for an Autonomous Vehicle (AV) in the freeway path. Three types of driving modes are analyzed. First was free flow, this constitutes that moving at the desired speed is determined at the beginning of the movement. Second case was car following, when overtaking or lane-change was impossible, distance or speed adaptation is executed using the variable acceleration/deceleration strategy. Third case was lane change or overtaking. For lane change or overtaking paths, the 5th degree polynomial is used to create a curvilinear path to changes its path to the left lane and then returns to its default lane. The velocity and relative distances of cars are main factors for decision making. All proper driving decisions algorithm is introduced. According to autonomous car desired velocity, in the two driving cases (fast and slow desired velocity for AV) are studied by simulation and their results analyzed and compared with together.</p> </abstract>ARTICLE2021-06-22T00:00:00.000+00:00Mathematical Model of a Tonal Rail Chain without Insulating Joints with Current Receiver in Shunt Mode<abstract> <title style='display:none'>Abstract</title> <p>One of the drawbacks of the currently used tonal rail chains without insulating joints is that when the train approaches the controlled section, the train begins to shunt this section at some distance before entry on him. In connection with the traffic light moves on this distance. But being that this distance depends on many variables, it constantly changes these variables. For eliminate this drawback, instead of the traditional potential receiver it is proposed to use electric current track receiver, which has a clear boundary fixation entry of train on the controlled section. By now developed and used methods for determining the main analytical expressions for analysis and synthesis tonal rail circuits with potential receivers in various operating modes, and the theoretical issues of tonal rail chains with current receivers were practically not considered, in this connection, the article considers the development of mathematical models for determining the absolute shunt sensitivity of tonal rail chains without isolating joints with current receivers and methods for calculating determination of the critical location of the minimum shunt sensitivity.</p> <p>The obtained expressions differ significantly from the known equations of absolute shunt sensitivity and the critical location of the minimum value of the shunt sensitivity and will allow to spend analyzing, synthesis and design of tonal rail chains without isolating joints with current receivers, that will allow to increase the safety of train traffic.</p> </abstract>ARTICLE2021-06-22T00:00:00.000+00:00Modern Sediment Model of Traffic Flow<abstract> <title style='display:none'>Abstract</title> <p>The work deals with the mathematical modeling of traffic phenomena. The submitted model is based on a prospective analogy of some described phenomena with particle sedimentation. Both the qualitative analysis of the model and the numerical experiment is carried out. Qualitative results of the research have been compared with the known data of supervision of the traffic on city highways. As a result, the main control parameters which can use for optimal traffic management are highlighted and justified.</p> </abstract>ARTICLE2021-06-22T00:00:00.000+00:00The Method of Determining the Optimal Transmission Resources Distribution of ICT Networks Modelled by Graphs<abstract> <title style='display:none'>Abstract</title> <p>The paper discusses the method of improvement of transmission properties of ICT networks by setting the correct distribution of transmission resources in order that it is possible to increase the resulting global probability of supporting the calls generated in the nodes included in the network. The method uses some parts of the graph theory. A minimum length path searching algorithm was used which made it possible to calculate the volume of movement transferred by individual edges of the graph describing the network. The coefficient of the distribution of transmission resources was determined and used to calculate the value of the resources in reference to a particular link, both in the case of equal and diverse movement generated in individual network nodes. A piece of software was developed which uses the results of applying the above-mentioned algorithm to prepare the files describing the analyzed structures in order to carry out simulation tests. The views and analyses are illustrated by examples, and the resulting effects of the influence of the introduction of the method of dividing network resources into transmission properties of a network modelled by graphs are shown in the charts included.</p> </abstract>ARTICLE2021-06-22T00:00:00.000+00:00Genetic Algorithm for the Pick-up and Delivery Problem with Time Window by Multi-Compartment Vehicles<abstract> <title style='display:none'>Abstract</title> <p>In this article we focus on multi-compartment vehicles that have to pick-up goods from suppliers and deliver them to various customers. Usually these goods cannot be transported by single-compartment vehicles due to the fact that some products are harmful to others: incompatibility between products. It is therefore a question of satisfying a set of customers while respecting the constraints linked to the capacity of each vehicle compartment, each type of product and ensuring that each supplier is visited before his customer. Our work consists firstly of mathematically modelling the problem described and secondly of solving it using methods due to its complexity. In this case we use the genetic algorithm to solve the pick-up and delivery problem of goods with a time window provided by multi-compartment vehicles. Our model allows to find a minimum distance and a minimum cost in the tour carried out by a reasonable number of vehicles.</p> </abstract>ARTICLE2021-06-22T00:00:00.000+00:00Constructing Reference Plans of Two-Criteria Multimodal Transport Problem<abstract> <title style='display:none'>Abstract</title> <p>The object of this study is a multicriteria transport problem, being stated for availability of several means of cargo delivery, meaning a multimodal transport problem. The optimization criteria of the multimodal transport problem described above are two objective functions of minimizing total transportation costs and level of transport risks. Three types of transport were selected for research: automobile, rail and river (inland waterway). The results of the study lay the foundation for development of a new valid algorithm for solving multimodal transport problems like multi-criteria optimization ones. The main advantage of such an algorithm lies in its higher potential convergence rate compared to classical numerical optimization methods, which now are predominantly used to solve the problems of this type. This advantage may not be decisive, but it appears to be at least quite an important argument when choosing the method of realization for two-criteria multimodal transport problems earlier considered, especially, in case of a large dimension. Moreover, the algorithm described in the work can be applied to similar problems with any number of types of transport and optimization criteria.</p> </abstract>ARTICLE2021-04-23T00:00:00.000+00:00Intelligent Traffic Management: A Review of Challenges, Solutions, and Future Perspectives<abstract> <title style='display:none'>Abstract</title> <p>Recent years have witnessed a colossal increase of vehicles on the roads; unfortunately, the infrastructure of roads and traffic systems has not kept pace with this growth, resulting in inefficient traffic management. Owing to this imbalance, traffic jams on roads, congestions, and pollution have shown a marked increase. The management of growing traffic is a major issue across the world. Intelligent Transportation Systems (ITS) have a great potential in offering solutions to such issues by using novel technologies. In this review, the ITS-based solutions for traffic management and control have been categorized as traffic data collection solutions, traffic management solutions, congestion avoidance solutions, and travel time prediction solutions. The solutions have been presented along with their underlying technologies, advantages, and drawbacks. First, important solutions for collecting traffic-related data and road conditions are discussed. Next, ITS solutions for the effective management of traffic are presented. Third, key strategies based on machine learning and computational intelligence for avoiding congestion are outlined. <bold>Fourth, important solutions for accurately predicting travel time are presented.</bold> Finally, avenues for future work in these areas are discussed.</p> </abstract>ARTICLE2021-04-23T00:00:00.000+00:00A Reliability-Exploitation Analysis of a Static Converter Taking Into Account Electromagnetic Interference<abstract> <title style='display:none'>Abstract</title> <p>The paper presents issues associated with the impact of electromagnetic interference on static converters, which exploitation in a railway transport environment. The measurements of an electromagnetic field emitted by a static converter were shown. Designs of this kind are exploitation in railway facilities, therefore, they should not disturb the functioning of other equipment, the rail traffic control systems, in particular. As a result of the EMC tests, it was concluded that the permissible values of conducted interference emissions were exceeded. An analysis of the obtained results enabled developing a research model, and a further reliability and exploitation analysis, taking into account electromagnetic interference. This, in turn, enabled determining a relationship allowing to determine the probability of a static converter staying in a state of full ability. The presented discussions regarding a static converter, taking into account electromagnetic interference, allow for the numerical assessment of different types of solutions (technical and organizational), which can be implemented in order to mitigate the impact of electromagnetic interference on a system’s functioning.</p> </abstract>ARTICLE2021-04-23T00:00:00.000+00:00Ultra-Wideband Pulse Radar with Discrete Stroboscopic Receiver for Detection of Small Targets Behind Dielectric Obstacles<abstract> <title style='display:none'>Abstract</title> <p>Increasing requirements in the field of security, in particular in the transport sector, the rescue work, the inviolability of private property and others urged to research work in the field of radar monitoring people, vehicles or other objects in the environment that not allow make so using the most popular and available technology for production and analysis of video images. These conditions of poor visibility, or even lack thereof, are darkness, bad weather, smoke, dust, wall (roof) buildings and the vehicle body. Existing instruments and special equipment occupy a certain niche in this area, mainly for counter-terrorism operations. However, such equipment is not readily available and extremely high price. In the paper presented research is development of the group’s existing radar technology in the field of location through opaque obstacles.</p> </abstract>ARTICLE2021-04-23T00:00:00.000+00:00How Does Pedestrian-Driver Behavior Influence in the Number of Crashes? A Michigan’s Case Study<abstract> <title style='display:none'>Abstract</title> <p>This study provides with a safety assessment of the pedestrian’s crash data in one of the largest cities of the state of Michigan, Grand Rapids. Crash data reviewed included a 9-year period between years 2010 and 2018. Crash clusters with largest number of accidents were selected to perform analysis based on the normalization of crash with population (using Census Bureau information). Geographic Information System (GIS) software was used to gather this data using a 250-feet buffer around the clusters. Also, GIS was used to identify the infrastructure design and locations nearby the studied area (e.g. schools and hospitals) to understand the crash environments. Observation of the associated factors with pedestrian crashes were studied at the location of interest. An analysis of all safety efforts was completed and a list of recommendations and possible implementation strategies (e.g. pedestrian countermeasures). Finally, it was found that four types of pedestrian crashes were most representative that crashes involved left-turning vehicle, crashes involved right-turn vehicle, crashed involved pedestrian in crosswalk and through traffic, and pedestrian were not cross at designated cross location</p> </abstract>ARTICLE2021-04-23T00:00:00.000+00:00Road Design Criteria and Capacity Estimation Based on Autonomous Vehicles Performances. First Results from the European C-Roads Platform and A22 Motorway<abstract> <title style='display:none'>Abstract</title> <p>Several European road operators and authorities joined the <italic>C-Roads Platform</italic> with the aim of harmonising the deployment activities of cooperative intelligent transport systems (C-ITS). C-ITS research is preliminary to future automated-driving vehicles. The current conventional highways were designed on traditional criteria and models specifically developed for traffic flows of manually guided vehicles. Thus, this article describes some new criteria for designing and monitoring road infrastructures on the basis of performance features of autonomous (or <italic>self-driving)</italic> vehicles.</p> <p>The new criteria have been adopted to perform an accurate conformity control of the <italic>A22 Brenner motorway</italic>, included in the <italic>C-Roads Platform,</italic> and also to ascertain whether in future it may be travelled by automated vehicles in safety conditions. Always in accordance with the technical and scientific insights required by the C-Roads Platform, a traffic model has been implemented to estimate how the A22 capacity increases compared to current values, by taking various percentages of automated or manual vehicles into consideration. The results given by theoretical models indicate that the highway will be able to be travelled by automated vehicles in safety conditions. On the other hand, the lane capacity is due to increase up to 2.5 times more than the current capacities, experimentally determined through traffic data collected from 4 highway sections by means of Drake’s flow model.</p> </abstract>ARTICLE2021-04-23T00:00:00.000+00:00Impact of Regional Climate Change on the Infrastructure and Operability of Railway Transport<abstract> <title style='display:none'>Abstract</title> <p>This article considers various aspects of the impact of climate change on the railway infrastructure and operations. A brief international overview and the importance of this issue for Russia are given. Temperature effects, permafrost thawing, strong winds, floods and sea level rise, long-term effects, and adaptation measures are discussed. In conclusion, the authors give several recommendations on further research in this area, and highlight that special attention should be given to the areas in the Russian Federation which already face or might soon experience damage from storm events or flooding and sea level rise, namely Kaliningrad Region on the Baltic Sea, the area between Tuapse and Adler in Krasnodar Region on the Black Sea, and on Sakhalin Island from the side of the Sea of Japan.</p> </abstract>ARTICLE2021-04-23T00:00:00.000+00:00Digital Technologies for Improving Logistics Performance of Countries<abstract> <title style='display:none'>Abstract</title> <p>The logistics performance has a crucial role in the industrial and economic development of countries. This study aims to underline implications for policy makers in improving the logistics performance of countries in terms of Industry 4.0. For this purpose, the effect of digitalisation on logistics performance is analysed by using correlation and multiple regression analysis. The empirical study builds upon dimensions and indicators of the Digital Economy and Society Index (DESI) and Logistics Performance Index (LPI) of the World Bank. The results indicate that governmental policies should target to deliver sound framework conditions for the generation of human capital (here: ICT specialists), sustainable usage of internet services (e.g. professional social networks, online sales, etc.), integration of digital technologies (e.g. Big Data, Cloud computing, etc.), as well as digital connectivity (here: fixed broadband and 4G coverage) in order facilitate improvement of logistics performance.</p> </abstract>ARTICLE2021-04-23T00:00:00.000+00:00System Architecture for Scenario-In-The-Loop Automotive Testing<abstract> <title style='display:none'>Abstract</title> <p>The paper describes a mixed reality environment for testing highly automated vehicle functions. The proposed Scenario-inthe-Loop test system connects real-time computer simulation with real elements being applicable at automotive proving ground. The paper outlines necessary hardware and software requirements and proposes basic system architecture. The limitation and bottleneck of the system are also identified: latency of the wireless communication constraints the accuracy of the test system. However, the presented framework can contribute to efficient development, testing and validation of automated cars. The Scenario-In-The-Loop architecture has also been justified by real-world demonstration using an experimental 5G New Radio network technology.</p> </abstract>ARTICLE2021-04-23T00:00:00.000+00:00Complex Mathematical Models for Analysis, Evaluation and Prediction of Aqueous and Atmospheric Environment of Latvia<abstract xml:lang="en"><title style='display:none'>Complex Mathematical Models for Analysis, Evaluation and Prediction of Aqueous and Atmospheric Environment of Latvia</title><p>In present paper the authors consider the complete statements of initial-boundary problems for the modelling of various aspects of aqueous (3 models) and atmospheric systems (2 models) in Latvia. All the proposed models are described in terms of differential equations theory (using both ordinary differential equations and partial differential equations) and are regarded to be the evolutional models. Two of the three aqueous system models being studied are intended to describe the natural aquatic media ecosystems while the other models are aimed at studying environmental pollution processes.</p></abstract>ARTICLE2012-03-20T00:00:00.000+00:00en-us-1