Svetlobni opozorilniki hitrosti v cestnem prometu : diplomsko deloBojan Kerin
, 2010, diplomsko delo
Opis: V diplomski nalogi smo se osredotočili na področje povečanja prometne varnosti s pomočjo svetlobnih opozorilnikov hitrosti. Na kratko smo poskušali povzeti trenutno stanje varnosti v cestnem prometu na področju Evropske unije in jo primerjali z nacionalno problematiko. Pod drobnogled smo vzeli problematiko omejevanja hitrosti, ki je ključni faktor prometnih nesreč s hudimi telesnimi poškodbami in s smrtnim izidom, ki puščajo posledice tako na ljudeh kot tudi na samem gospodarstvu. Po študijah, ki smo jih opravili (pri izdelavi diplomskega dela), smo prišli do zaključka, da bi uporaba svetlobnih opozorilnikov hitrosti pripomogla k izboljšanju prometne varnosti, še zlasti na črnih točkah. Z uporabo takšnih naprav se izboljša percepcija prometne signalizacije zaradi osvetlitve iz sekundarnega vira svetlobe. Uporabljamo jih lahko v namene statističnih analiz stanja na cestah. Zaradi omejevanja hitrosti se posledično izboljša tudi kakovost življenja ljudi, ki živijo neposredno ob cesti, hkrati pa se doseže zmanjšanje izpustov strupenih plinov iz vozil. Z modifikacijo bi lahko svetlobne opozorilnike hitrosti uporabljali tudi na nivojskih prehodih čez železnico, ki bi nadomestili drage zapornice. Prednost svetlobnih opozorilnikov hitrosti je možnost njihove nadgradnje in uporabe za prihajajoče inteligentne prometne sisteme.
Ključne besede: svetlobni opozorilniki hitrosti, vizija nič, omejevanje hitrosti, prometna varnost, črne točke, light-based speed warning system, vision zero, speed limitation, traffic safety, black spots
Objavljeno: 03.09.2010; Ogledov: 2330; Prenosov: 125
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Using neural networks in the process of calibrating the microsimulation models in the analysis and design of roundabouts in urban areasIrena Ištoka Otković
, 2011, doktorska disertacija
Opis: The thesis researches the application of neural networks in computer program calibration of traffic micro-simulation models. The calibration process is designed on the basis of the VISSIM micro-simulation model of local urban roundabouts.
From the five analyzed methods of computer program calibration, Methods I, II and V were selected for a more detailed research. The three chosen calibration methods varied the number of outgoing traffic indicators predicted by neural networks and a number of neural networks in the computer program calibration procedure. Within the calibration program, the task of neural networks was to predict the output of VISSIM simulations for selected functional traffic parameters - traveling time between the measurement points and queue parameters (maximum queue and number of stopping at the roundabout entrance). The Databases for neural network training consisted of 1379 combinations of input parameters whereas the number of output indicators of VISSIM simulations was varied. The neural networks (176 of them) were trained and compared for the calibration process according to training and generalization criteria. The best neural network for each calibration method was chosen by using the two-phase validation of neural networks.
The Method I is the calibration method based on calibration of a traffic indicator -traveling time and it enables validation related to the second observed indicator – queue parameters. Methods II and V connect the previously described calibration and validation procedures in one calibration process which calibrates input parameters according to two traffic indicators.
Validation of the analyzed calibration methods was performed on three new sets of measured data - two sets at the same roundabout and one set on another location. The best results in validation of computer program calibration were achieved by the Method I which is the recommended method for computer program calibration.
The modeling results of selected traffic parameters obtained by calibrated VISSIM traffic model were compared with: values obtained by measurements in the field, the existing analysis methods of operational roundabouts characteristics (Lausanne method, Kimber-Hollis, HCM) and modeling by the uncalibrated VISSIM model. The calibrated model shows good correspondence with measured values in real traffic conditions. The efficiency of the calibration process was confirmed by comparing the measured and modeled values of delays, of an independent traffic indicator that was not used in the process of calibration and validation of traffic micro-simulation models.
There is also an example of using the calibrated model in the impact analysis of pedestrian flows on conflicting input and output flows of vehicles in the roundabout. Different traffic scenarios were analyzed in the real and anticipated traffic conditions.
Ključne besede: traffic models, traffic micro-simulation, calibration of the VISSIM model, computer program calibration method, neural networks in the calibration process, micro-simulation of roundabouts, traffic modeling parameters, driving time, queue parameters, delay
Objavljeno: 02.06.2011; Ogledov: 3864; Prenosov: 272
Celotno besedilo (13,21 MB)
The use of micro-simulation in determining the capacity of a roundabout with a multi-channel pedestrian flowTomaž Tollazzi
, Tone Lerher
, Matjaž Šraml
, 2008, izvirni znanstveni članek
Opis: The main purpose of this paper is to analyse the influence of the multi-channel pedestrian flow on the capacity of the one-lane roundabout, using discrete simulation methods. The proposed model is based on the theory of the expected time void between the units of pedestrian traffic flow, which have the priority when crossing the arm of the roundabout. The proposed model represents an upgrade of the previous research in the field of modelling traffic flows in the one-lane roundabout. While the previous model of the pedestrian crossing is handled as the single-channel system in which the pedestrians arrive randomly from one side of the pedestrian crossing only, the proposed model deals with the multi-channel system in which the pedestrians arrive randomly from both sides of the pedestrian crossing. In thi sway the mathematical model can better illustrate the real conditions. The previous model considers only the disturbances of entry traffic flow of motorised vehicles caused by the pedestrian flow crossing the roundabout arm. The proposed model considers the disturbances caused by the circular traffic flow of motorised vehicles as well. A simulation analysis has been conducted on the roundabout at Koroška Street in Maribor, in which the counting of the motorised traffic flow and the pedestrian flow has been performed in the morning peek hour. The results of the analysis have indicated a high reserve of the capacity for pedestrians who arrive from the left and right sides of the roundabout with regard to motorised vehicles in the analysed arm of the roundabout. The real reserve of the capacity would otherwise be smaller in case of enlargement of the motorised vehicle flow in the future. Nevertheless it would be high enough for an undisturbed traffic flow of motorised vehicles through the roundabout to be possible. The presented methodology represents a practicable and adaptable tool for planning the roundabout capacity in practice and for the sensitivity analysis of individual variables on the throughput capacity of the roundabout.
Ključne besede: roundabout, pedestrian flow, traffic flow modeling, simulation models
Objavljeno: 31.05.2012; Ogledov: 1413; Prenosov: 31
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Encyclopedia of complexity and systems science
slovar, enciklopedija, leksikon, priročnik, atlas, zemljevid
Opis: Encyclopedia of Complexity and Systems Science provides an authoritative single source for understanding and applying the concepts of complexity theory together with the tools and measures for analyzing complex systems in all fields of science and engineering. The science and tools of complexity and systems science include theories of self-organization, complex systems, synergetics, dynamical systems, turbulence, catastrophes, instabilities, nonlinearity, stochastic processes, chaos, neural networks, cellular automata, adaptive systems, and genetic algorithms. Examples of near-term problems and major unknowns that can be approached through complexity and systems science include: The structure, history and future of the universe; the biological basis of consciousness; the integration of genomics, proteomics and bioinformatics as systems biology; human longevity limits; the limits of computing; sustainability of life on earth; predictability, dynamics and extent of earthquakes, hurricanes, tsunamis, and other natural disasters; the dynamics of turbulent flows; lasers or fluids in physics, microprocessor design; macromolecular assembly in chemistry and biophysics; brain functions in cognitive neuroscience; climate change; ecosystem management; traffic management; and business cycles. All these seemingly quite different kinds of structure formation have a number of important features and underlying structures in common. These deep structural similarities can be exploited to transfer analytical methods and understanding from one field to another. This unique work will extend the influence of complexity and system science to a much wider audience than has been possible to date.
Ključne besede: cellular automata, complex networks, computational nanoscience, ecological complexity, ergodic theory, fractals, game theory, granular computing, graph theory, intelligent systems, perturbation theory, quantum information science, system dynamics, traffic management, chaos, climate modelling, complex systems, dynamical sistems, fuzzy theory systems, nonlinear systems, soft computing, stochastic processes, synergetics, self-organization, systems biology, systems science
Objavljeno: 01.06.2012; Ogledov: 1643; Prenosov: 85
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Mathematical model of IRIS replication mechanism for the simulation of tactical networksJože Mohorko
, Matjaž Fras
, 2009, izvirni znanstveni članek
Opis: The Multilateral Interoperability Programme (MIP) was established to promote more successful and better harmonized operational functions for international peace-keeping forces. The C2IEDM/JC3IEDM (Command and Control Information Exchange Data Model) ensures the interconnection of Command and Control Information Systems (C2ISs) throughout all levels, from the corps down to the lower ranks. The usability of C2ISs highly correlates with the capacities of data information carriers, and the need is growing for greater capacity and reliability of transmission media and cryptographic message security. Simulation of tactical networks is an important task in planning military missions. Such methodologies assure a higher probability of success during critical tactical operations. This article focuses on a new radio network modeling method for the C2IS, which is verified by the OPNET simulation environment. This modeling method can be used in tactical radio network planning and optimization processes.
Ključne besede: communications, tactical networks, tactical radio networks, traffic modelling, radio network modeling, simulations, C2IS
Objavljeno: 01.06.2012; Ogledov: 1358; Prenosov: 70
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Transport and tourismStephen Page
, 1999, učbenik za višje in visoke šole
Ključne besede: tourism, tourist industry, transport, traffic, travel, multidisciplinary approach, industries, infrastructure, supply, demand, management, services, quality, air traffic, enterprises, directories
Objavljeno: 01.06.2012; Ogledov: 2083; Prenosov: 40
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International economicsRobert J. Carbaugh
, učbenik za višje in visoke šole
Ključne besede: international economic relations, globalization, models, economic theories, economic equilibrium, regulation, international finances, tariffs, international traffic of payments, international banks, international banking, international trade, industrial policy, trade policy, exchange rate, international exchange, world, payments, open economy, macroeconomics, economic policy, developed countries, developing countries, multinational companies, balance of payments, texbooks, cases, case study
Objavljeno: 02.06.2012; Ogledov: 1203; Prenosov: 24
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