Assessment and modelling of urban bypasses’ influence on transport flows distribution in street network

Disertacijoje nagrinėjama aplinkkelių ir greito eismo gatvių vietos parinkimo mieste problema. Pagrindinis darbo objektas – aplinkkelių ir greito eismo gatvių padėties poveikis transporto srautams gatvių tinkle. Panaudojant transporto srautų modeliavimą sukurta aplinkkelio ir greito eismo gatvės vietos parinkimo metodika, nereikalaujanti sudėtingo, daug laiko ir lėšų atimančio viso miesto transporto srautų modeliavimo. Metodika yra pritaikyta dviem didžiausiams Lietuvos miestams – Vilniui ir Kaunui. Darbo tikslas – sudaryti aplinkkelių ir greito eismo gatvių vietos parinkimo metodiką, panaudojant transporto srautų modeliavimą, ją pritaikyti praktikoje, ir siekti sumažinti miesto gyventojų patiriamas laiko sąnaudas susisiekimui. Disertaciją sudaro įvadas, 3 skyriai, bendrosios išvados, literatūros sąrašas, publikacijų sąrašas ir 11 priedų. Įvade trumpai aptariama tiriamoji problema, darbo aktualumas, aprašomas tyrimo objektas, formuluojamas darbo tikslas ir uždaviniai, aprašoma mokslinis darbo naujumas, ginamieji teiginiai. Įvado pabaigoje pristatomos autoriaus paskelbtos publikacijos disertacijos tema, pranešimai konferencijose ir pateikiama disertacijos struktūra. Pirmame skyriuje pateikiama literatūros apžvalga nagrinėjama tematika. Atliekama mokslinių darbų analizė. Taip pat įvertinami Lietuvos Respublikos bei Europos Sąjungos dokumentai, formuojantys transporto politiką. Antrajame skyriuje pristatomas sukurtas idealizuoto miesto transporto modelis. Darbo metu yra sumodeliuota 90 skirtingų aplinkkelių ir (ar) greito eismo gatvių įrengimo padėties variantų. Apibendrinus gautus modeliavimo rezultatus ir atlikus jų analizę, sudaryta miesto aplinkkelių ir greito eismo gatvių vietos parinkimo metodika. Trečiajame skyriuje aptarti pagrindiniai transporto tyrimų būdai, – išsiskiriantys prieinamumu ir minimalia kaina bei užtikrinantys pakankamą aprėptį ir tikslumą. Išnagrinėtos dviejų didžiausių Lietuvos miestų, – Vilniaus ir Kauno, susisiekimo sistemos, nustatyti jų pagrindiniai parametrai bei pritaikyta aplinkkelių ir greito eismo gatvių vietos parinkimo metodika. Disertacijos tema paskelbtos penkios mokslinės publikacijos, iš kurių keturios referuojamuose duomenų bazės Clarivate Analytics (ISI Web of Science) recenzuojamuose mokslo žurnaluose. Atliktų tyrimų rezultatai paskelbti dvejose Lietuvos ir vienoje užsienio konferencijose.Disertacij

Application of Google-based Data for Travel Time Analysis: Kaunas City Case Study

Recently, new traffic data sources have emerged raising new challenges and opportunities when applying novel methodologies. The purpose of this research is to analyse car travel time data collected from smartphones by Google Company. Geographic information system (GIS) tools and Python programming language were employed in this study to establish the initial framework as well as to automatically extract, analyse, and visualize data. The analysis resulted in the calculation of travel time fluctuation during the day, calculation of travel time variability and estimation of origin-destination (OD) skim matrices. Furthermore, we accomplished the accessibility analysis and provided recommendations for further research.</p

A finite element model in a form of structural dynamic equation for the transient analysis of pressure in pipelines

The finite element model of transient pressure pulse propagation in a pipeline is presented in the form of the standard structural dynamic equation, which combines steady flow analysis for obtaining the initial conditions of the flow in the form of pressures and flow rates and non-linear dynamic analysis by using explicit numerical integration techniques. Three options of simplification of governing equation set have been analyzed. At low values of steady flow speed many non-linear and convection terms could be omitted, while at the flow speeds comparable with the wave propagation speed the full equation system has been analyzed. The full equation system analysis involves the techniques ensuring corrections of the initial conditions and of the nodal flow rate balance. The investigated pipelines may contain large number of branches and loops. Parts of large pipelines are analyzed as separate sub-models by employing non-reflecting boundary conditions at the cut boundaries. Properties of pressure pulse front degradation as it propagates through branching points of the pipeline can be examined

A finite element model in a form of structural dynamic equation for the transient analysis of pressure in pipelines

The finite element model of transient pressure pulse propagation in a pipeline is presented in the form of the standard structural dynamic equation, which combines steady flow analysis for obtaining the initial conditions of the flow in the form of pressures and flow rates and non-linear dynamic analysis by using explicit numerical integration techniques. Three options of simplification of governing equation set have been analyzed. At low values of steady flow speed many non-linear and convection terms could be omitted, while at the flow speeds comparable with the wave propagation speed the full equation system has been analyzed. The full equation system analysis involves the techniques ensuring corrections of the initial conditions and of the nodal flow rate balance. The investigated pipelines may contain large number of branches and loops. Parts of large pipelines are analyzed as separate sub-models by employing non-reflecting boundary conditions at the cut boundaries. Properties of pressure pulse front degradation as it propagates through branching points of the pipeline can be examined

The impact of cost-benefit analysis on decision making concerning the development of the urban transport system: case of Kaunas City

The formulation of scenarios for developing the urban transport infrastructure requires decisions mainly based on the intuition of experts in transport and highly influenced by public interest groups, business entities and political opinions. However, the reached decisions sometimes fail to be the most efficient. Therefore, to avoid errors and ensure the development of a sustainable transport system, the economical appraisal of infrastructure development scenarios is necessary. The economic evaluation of the developed scenarios can be carried out through macro-simulation and cost-benefit analysis. This paper deals with the Kaunas City Master Plan providing solutions to transport infrastructure development. According to the Master Plan, solutions can be classified considering 3 cathegories (priorities), although the detailed sequence of implementation is not given. With the help of macro-simulation, this study arranged Master Plan solutions into scenarios, checked all 20 scenarious and established an implementation order based on the theory of cost benefit analysis. The identified order substantially differs from the priorities set in the Master Plan

Ranking conceptual locations for a park-and-ride parking lot using EDAS method

Prilikom planiranja lokacije za Park&Ride (skraćeno P&R) parkirališta treba istovremeno uzeti u obzir ekonomske, društvene, urbane, okolišne i druge čimbenike. Kako bi se navedena zadaća pojednostavnila, odabrane su tri idejne lokacije za P&R parkirališta u blizini zapadne obilaznice grada Vilniusa (Litva). Cilj je ovog rada odrediti ključne kriterije koji unapređuju uspješno funkcioniranje osobnog i javnog prijevoza te rangirati navedene idejne lokacije primjenom višekriterijske metode odlučivanja EDAS (engl. Evaluation based on Distance from Average Solution).The decision regarding the location of a Park-and-Ride (P&R) parking lot must be taken by simultaneously considering economic, social, urban, environmental, and other factors. This task is simplified by selection of three conceptual locations for P&R parking lots near the Vilnius western bypass. The aim of the paper is to identify key criteria that promote successful functioning of the private and public transport systems, and to rank these conceptual locations using the Evaluation based on Distance from Average Solution (EDAS) multiple-criteria decision-making method

Modelling a passenger car system based on the principles of sustainable mobility in Vilnius City

The growing rate of motorization and the use of passenger cars have a worsening effect on traffic conditions in the streets of Vilnius City. Moreover, adverse urbanisation processes (i.e. migration to suburban areas) make a huge effect on the behaviour of travelling. A deeper analysis of these processes requires large data amounts and techniques for analysing transportation. The study is aimed at preparing and assessing the scenarios of developing passenger car transport through the prism of sustainability indicators. A plan for case study-based hypothetical mobility management explores a series of future scenarios improving transportation diversity and changes in modes for travellers. These scenarios are developed with respect to developments anticipated in the Master Plan of the City of Vilnius and aims at identifying the effect of a new public transport network on the motorized transport system during the morning peak in the hypothetical year 2025. Mobility management through transportation diversity increases travelling options, encourages travellers to choose the most efficient mode and tends to eliminate car dependency that otherwise occurs in urban areas. The development of a public transport route network in Vilnius City creates real preconditions for implementing a sustainable transport system thus giving a priority to the development of a new and fast transport mode. The planned routes of the new transport mode allows significantly reducing the necessity for the use of private motorized transport and influencing the total structure of travels thus making it possible for a large number of people to reach destination by public transport

Analysis of Kaunas city population and workplace density in terms of mobility / Kauno miesto gyventojų ir darbo vietų tankio analizė transportiniu požiūriu

In city population and workplace density distributions directly influences the number of trips, travel means and even leads to changes of energy consumption rate. This paper is aimed to perform Kaunas city workplace density and population density analysis and to evaluate the parameters impact on the mobility of the population. The main focus is on the Kaunas population and workplace distribution. For that population density and workplace density maps are made. Initial data is processed by geographic information system (GIS), allowing to represent them in a very clear way. Conclusions are given based on conducted analysis and other relevant sources of information. Santrauka  Gyventojų bei darbo vietų pasiskirstymas mieste turi tiesioginės įtakos gyventojų atliekamų kelionių skaičiui, kelionių būdui ir lemia transporto sistemos suvartojamą energijos kiekį. Šio darbo tikslas – atlikti Kauno miesto darbo vietų ir gyventojų tankio analizę bei įvertinti šių parametrų įtaką gyventojų mobilumui. Straipsnyje nagrinėjamas Kauno miesto gyventojų ir darbo vietų pasiskirstymas. Tam yra sudaromi gyventojų bei darbo vietų tankio žemėlapiai. Pradiniai duomenys apdorojami, analizuojami ir grafiškai pateikiami schemomis naudojant geografines informacines sistemas (toliau GIS). Remiantis analizės rezultatais ir atliktos apklausos rezultatais formuluojamos apibendrinančios išvados. Raktiniai žodžiai: Kauno miestas, darbo vietų tankis, gyventojų tankis, regresinė analizė

Application of Google-based Data for Travel Time Analysis: Kaunas City Case Study

Recently, new traffic data sources have emerged raising new challenges and opportunities when applying novel methodologies. The purpose of this research is to analyse car travel time data collected from smartphones by Google Company. Geographic information system (GIS) tools and Python programming language were employed in this study to establish the initial framework as well as to automatically extract, analyse, and visualize data. The analysis resulted in the calculation of travel time fluctuation during the day, calculation of travel time variability and estimation of origin-destination (OD) skim matrices. Furthermore, we accomplished the accessibility analysis and provided recommendations for further research

Reducing a possibility of transport congestion on freeways using ramp control management

Merge junctions are the key elements in the freeway system, as they are likely to function as bottlenecks. Investigations into breakdown occurrence at ramp junctions have demonstrated that when the groups of several vehicles following each other enter the freeway from the ramp, they are expected to create ‘turbulence’ resulting from lane changes, decelerations of vehicles on the mainline and inevitably by the cars merging from the on-ramp. This turbulence can lead to breakdown when the level of mainline demand is adequately high. In other words, the impact of a ramp vehicle on capacity is higher than that of a mainline vehicle, which indicates that a part of vehicles will simultaneously occupy two lanes during the process of changing them thus momentarily decreasing the capacity of the link. This feature becomes particularly important near bottlenecks where it might reduce the already limited throughput. The article introduces the main approaches, methodology, principles and stages of transport demand management on freeways that are aimed at improving the operation quality of transport facilities, including road safety. The technique allows evaluating and optimizing a Ramp-Metering (RM) concept from the viewpoint of minimizing the length of queues on ramps and a possibility of transport congestion. The proposed algorithm estimates the probability of starting congestion formation on the ramp using objective information on traffic conditions in each segment of the highway, which is based on the criterion for vehicle density on the lane. The last chapter shows the examples of traffic flow optimization on Western bypass ramps in Vilnius comparing two strategies for access control management using one or several vehicles per lane. Conclusions, trends and work on future investigations are presented at the end of the article