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Delay, defined as the additional travel time, is a main indicator of the quality of traffic process at the signalized intersection and important input parameter in the traffic signal settings. Delay value can be determined by using non-experimental (analytical and simulation) and experimental methods. Analytical models provide a fast and simple procedure for their determination. This paper presents the result of comparing the delay values obtained using the relevant analytical models and the real values measured at the field. It was concluded, that none of the analyzed models do not fully estimated the real delay values, and that the minimum deviation is obtained by using HCM 2010. delay model.

Doktorska disertacija prikazuje originalan pristup analizi saobraćajnog procesa na signalisanoj raskrsnici i utvrđivanju osnovnog pokazatelja efikasnosti – vremenskih gubitaka. Aktuelne metode i modeli ne obezbeđuju preciznu procenu vrednosti gubitaka. Kao osnovni nedostaci navode se pojednostavljena teorijska interpretacija procesa u okviru neeksperimentalnih, odnosno indirektnost istraživanja i veličina uzorka u okviru eksperimentalnih metoda. Formiranje objektivnih metoda utvrđivanja gubitaka zahteva potpunu spoznaju procesa u kome dolazi do njihovog nastajanja. U radu je formirana metodologija istraživanja parametara u procesima kretanja vozila u zoni signalisane raskrsnice. Osnovu metodologije predstavlja metod utvrđivanja trajektorija kretanja vozila primenom GPS tehnologije prikupljanja podataka. Primenom metodologije obezbeđuje se formiranje trajektorija vozila visokog nivoa preciznosti i detaljnosti, što predstavlja osnovu za analizu saobraćajnog procesa, utvrđivanje vrednosti osnovnih parametara i njihovog uticaja na vremenske gubitke. Rezultati istraživanja na signalisanim raskrsnicama i formirani zaključci se u određenim segmentima razlikuju od onih koje su utvrdili drugi autori. Na osnovu istraživanja razvijen je analitički model vremenskih gubitaka za nezasićena stanja. U modelu, ukupni vremenski gubici se posmatraju na mikroskopskom nivou, kroz komponente gubitaka koje nastaju u procesima kretanja vozila u različitim tipovima trajektorija. Analitički model predstavlja osnovu formiranog metoda eksperimentalnog utvrđivanja vremenskih gubitaka (MEIS). U okviru metoda gubici se utvrđuju na osnovu direktnog istraživanja vremenske komponente kretanja svakog pojedinačnog vozila koje je ostvarilo vremenski gubitak. Na osnovu rezultata praktične primene na signalisanim raskrsnicama u Beogradu, zaključeno je da je formirani metod validan u postupku utvrđivanja ukupnih vremenskih gubitaka za nezasićena stanja, kao i da se njegovom primenom eliminišu neki od osnovnih nedostataka postojećih metoda utvrđivanja gubitaka... The Doctoral dissertation demonstrates an original approach to the analysis of traffic processes at a signalized intersection and to the determination of a key performance indicator – control delay. Current estimation methods and models do not provide accurate delay assessment. The main disadvantages of existing experimental models are the sample size and indirect research methods. On the other hand, in non-experimental methods, the deficiency is in the need for theoretical simplifications of the actual traffic processes. The determination of objective estimation methods requires comprehensive understanding of the processes where the delays are generated. This dissertation proposes a methodology for the determination of individual vehicle tracking and traffic flow parameters at a signalized intersection. The foundation of this methodology is the determination of traffic parameters using GPS data collection technology. The implementation of this method provides high resolution trajectory determination, which represents a good basis for traffic process analysis and the assessment of basic parameters and their impact on control delay. The obtained results and conclusions differ moderately in certain segments from those obtained and presented by other authors. The analytical delay model for unsaturated conditions is developed based on the realized research in this dissertation. Total delays in the model are recorded at the microscopic level and represented as delay components in various trip patterns. The analytical model represents the basis of the method for experimental delay estimation (MEIS). The control delay is determined directly by researching the time trace of each particular vehicle experiencing delays. The method is implemented and tested at several signalized intersections in Belgrade. The method is proved to be valid for total delay determination in unsaturated conditions. Correspondingly, some of the most important disadvantages of existing delay estimation methods are eliminated by its implementation...

Upravljanje saobraćajem na gradskim arterijama zasniva se na usaglašavanju rada svetlosnih signala na unapred definisanom nizu raskrsnica. Osnovni cilj procesa upravljanja je da plotun vozila formiran na početnoj raskrsnici prođe celokupnu arteriju bez zaustavljanja. Za projektovanje sistema upravljanja na gradskim arterijama neophodno je poznavanje karakteristika kretanja plotuna vozila kako bi se uspostavila funkcionalna veza između parametara rada signala i objekta upravljanja. Uzimajući u obzir nedostatak jedinstvene i precizne definicije plotuna vozila koji predstavlja osnovni objekat upravljanja, u doktorskoj disertaciji je formiran model za definisanje plotuna vozila, koji pripadnost vozila plotunu utvrđuje na osnovu dva parametra, intervala sleđenja i pozicije vozila. Tokom kretanja duž arterije na svako pojedinačno vozilo u plotunu utiču spoljašnji i unutrašnji faktori. Pod uticajem navedenih faktora dolazi do modifikacije plotuna koja se manifestuje kroz fenomen skupljanja ili rasturanja plotuna. Osnovni nedostatak postojećih modela kretanja plotuna odnose se na činjenicu da opisuju isključivo fenomen rasturanja plotuna. Međutim, transformacija urbanog saobraćajnog sistema dovela je do promena u karakteristikama kretanja plotuna vozila, koje za posledicu imaju sve češću pojavu skupljanja plotuna, što je dokazano na osnovu rezultata istraživanja. U više od 52% registrovanih plotuna zabeležen je fenomen skupljanja, čime je dokazano da postojeći modeli (Robertson i HCM) odstupaju od realnih podataka. Istraživanjem je utvrđeno da su najznačajniji unutrašnji faktori koji dovode do modifikacije plotuna, veličina plotuna i brzina kretanja plotuna. U disertaciji je dokazano da veličina plotuna dominantno utiče na karakteristike kretanja plotuna. Na osnovu rezultata istraživanja formiran je model baziran na funkcionalnoj zavisnosti između veličine plotuna i karakteristika kretanja plotuna. Predloženi model, koji predstavlja osnovni cilj disertacije, opisuje oba fenomena i rasturanje i skupljanje plotuna, čime je eliminisan osnovni nedostatak postojećih modela. Primenom modela na deonicama gradskih arterija, dokazano je da je formirani model validan i jednostavan za primenu. Urban arterial street traffic management is based on the defined number of consecutive traffic signals coordination. The main objective of coordination is to ensure that platoon of vehicles, formed at the initial intersection, pass arterial street without stopping. In order to determine a functional relationship between the traffic signal parameters and the control object, i.e. platoon of vehicles, it is necessary to know the platoon movement characteristics. This dissertation proposes the model for platoon definition, considering the lack of a unique and precise platoon definition in the literature. Proposed model for platoon definition is based on two parameters, the time headway and the vehicle position. Platoon movement characteristics depend on external and on internal factors which affect each vehicle in the platoon. The influence of these factors results in the platoon modification, which can be manifested by the dispersion or compression phenomenon. Existing models of platoon movement characteristics can predict only platoon dispersion phenomenon, which is at the same time their main disadvantage. However, the urban transport system transformation has caused changes in the platoon movement characteristics, which, as a result, more often lead to platoon compression phenomenon. Based on the conducted research, the compression phenomenon is recorded in more than 52% of platoons. For this reason, relevant models such as Robertson and HCM model do not provide an accurate prediction of vehicle platoon movement characteristics. This research proves that platoon movement characteristics mostly depends on platoon size and platoon speed, but platoon size has a dominant effect. Proposed model of platoon movement characteristics, as a primary goal of this dissertation, can predict both, platoon dispersion and platoon compression, and overcome the main disadvantages of relevant models. By applying the proposed model at several arterial streets in Belgrade, it is proved that the model is valid and easy to use.

U okviru ove disertacije razmatrani su problemi upravljanja saobraćajnim tokovima na izolovanoj signalisanoj raskrsnici i u zoni raskrsnica u fiksnom režimu rada. Takođe je razmatran i višekriterijumski problem upravljanja izlovanom signalisanom raskrsnicom koji je podrazumevao istovremeno upravljanje tokovima vozila i pešačkim tokovima. Problemi razmatrani u ovoj disertaciji po svojoj prirodi spadaju u probleme kombinatorne optimizacije. U slučaju fiksnog režima rada raskrsnice saobraćajni tokovi se grupišu u određeni broj faza. Svakoj fazi se dodeljuje određeni interval vremena za opsluživanje. Sa porastom broja faza raste i kombinatorna složenost razmatranog problema... This doctoral dissertation studies isolated signalized intersection traffic control problem. The dissertation also studies area-wide urban traffic control in the case of fixed time mode. Within the dissertation, we also discussed the multicriteria isolated signalized intersection traffic control problem, by taking into account driver and pedestrian delays. By their nature, all considered problems fall into area of difficult combinatorial optimization problems. In the case of fixed time control, traffic flows are served by being divided into a number of control phases, where at one time interval serves one phase and the next phase of the second interval, etc. As number of phases grows, complexity of combinatorial problems is more and more high...