Dissertations / Theses: 'Study of traffic flow'

1

Västlund, Filip. "Video Flow Classification : A Runtime Performance Study." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-56621.

Full text

Abstract:

Due to it being increasingly common that users' data is encrypted, the Internet service providers today find it difficult to adapt their service for the users' needs. Previously popular methods of classifying users data does not work as well today and new alternatives is therefore desired to give the users an optimal experience.This study focuses specifically on classifying data flows into video and non-video flows with the use of machine learning algorithms and with a focus on runtime performance. In this study the tested algorithms are created in Python and then exported into a C code implementation, more specifically the random forest and the gradient boosting trees algorithm.The goal is to find the algorithm with the fastest classification time relative to its accuracy, making the classification as fast as possible and the classification model to require as little space as possible.The results show that random forest was significantly faster at classification than gradient boosting trees, with initial tests showing it to be roughly 7 times faster after compiler optimization. After optimizing the C code random forest could classify more than 250,000 data flows each second with decent accuracy. Neither of the two algorithms required a lot of space (<3 megabyte).
HITS, 4707

APA, Harvard, Vancouver, ISO, and other styles

2

Lehman, Mark. "A study of traffic flow using GPS data." Connect to this title online, 2005. http://hdl.handle.net/1811/557.

Full text

Abstract:

Thesis (Honors)--Ohio State University, 2005
Title from first page of PDF file. Document formattted into pages: contains, 25.; also includes graphics. Includes bibliographical references (p. 25) Available online via Ohio State University's Knowledge Bank.

APA, Harvard, Vancouver, ISO, and other styles

3

Gopalan, Ganesh. "Improvement of traffic flow conditions using access management techniques : a netsim study /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p1426063.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Arezki, Y. "Algorithms for the traffic assignment problem with a fixed demand." Thesis, University of Leeds, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379651.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

CHEN, YIDI. "A Numerical Study of Multi-class Traffic Flow Models." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu158714737847054.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Fong, Pui San. "Assessment of roundabout in urban road network :a case study of Macau." Thesis, University of Macau, 2017. http://umaclib3.umac.mo/record=b3691706.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Sultan, Beshr. "The study of motorway operation using a microscopic simulation model." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.322018.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Toth, Christopher Stephen. "Empirical study of the effect of offramp queues on freeway mainline traffic flow." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53098.

Full text

Abstract:

The dissertation examines the relationship between the number of lane changes, the speed of the ramp lane, and the location upstream of the ramp split. Analyses indicate the number of lane changes exhibits a parabolic relationship with respect to the ramp lane speed, and the number of lane changes exhibits gamma-distributed relationship with respect to the distance upstream of the ramp. The macroscopic lane changing model presented is best characterized as the development of generalized lane-changing relationships, and provides a starting point from which more complex corridor-level models can be developed. This study also identifies an unusual car-following behavior exhibited by certain lane-changing drivers. When the target lane is moving slowly, some lane-changing drivers will slow down, causing a disruption in their initial lane. Regression analysis is used to estimate the speed upstream of the initial lane to indicate the disruption is responsible for the lateral propagation of congestion. The lane choice of exiting vehicles is also studied. Lane choice appears to be a function of origin/destination, and freeway speed. As speeds in the general purpose lanes decrease, exiting vehicles are more likely to wait longer to move into the exit ramp lanes, resulting in an increased lane changing density. Results from this study are expected to have the greatest impact on microscopic lane-change model validation. Additionally, results have implications for design and safety issues associated with freeway ramps. As data collection technologies improve and data becomes increasingly available, this research provides the basis for the further development of more elaborate lane-changing models.

APA, Harvard, Vancouver, ISO, and other styles

9

Queiroz, Isabela Nascimento Fernandes De. "Study on methodology for analysis of traffic flow based on video image data." 京都大学 (Kyoto University), 2005. http://hdl.handle.net/2433/145385.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Lazim, Mohamad Alias. "Econometric forecasting models and model evaluation : a case study of air passenger traffic flow." Thesis, Lancaster University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.296880.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

Shinouda, Michael Magdy Rizk. "Study of contraflow operations for hurricane evacuation." Birmingham, Ala. : University of Alabama at Birmingham, 2009. https://www.mhsl.uab.edu/dt/2010r/shinouda.pdf.

Full text

APA, Harvard, Vancouver, ISO, and other styles

12

Hsieh, Long-Bing Benson. "A study of the accuracy and reliability of traffic recording devices." Ohio : Ohio University, 1996. http://www.ohiolink.edu/etd/view.cgi?ohiou1174611257.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Lagervall, Malin, and Sandra Samuelsson. "Microscopic Simulation of Pedestrian Traffic in a Station Environment: A Study of Actual and Desired Walking Speeds." Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-112100.

Full text

Abstract:

In order to attract pedestrians to travel with public transport instead of private cars, the layout of interchange stations is important and should be designed in an effective way. Microscopic simulation of pedestrians can be used to evaluate different layout scenarios or a future increase in flow. The simulation software Viswalk was investigated, where the movements of pedestrians are based on a social force model,. The purpose of this thesis was to investigate simulated walking speeds for different flow levels and to investigate the effects of dividing pedestrians into types with different desired speeds. The aim was to find a desired speed distribution that can be used for different flow levels. Field studies have been performed to collect pedestrian traffic data with a video camera at Stockholm Central Station. Two disjoint flow levels were identified and used to investigate if the same desired speed distribution could be used for different flow levels. The average observed walking speed was 1.33 metres per second at the low flow level and 1.25 metres per second at the high flow level. The error was 4.5 percent between the average observed walking speed and the average simulated walking speed when the optimal desired speed distribution at the low flow level was used at the high flow level. Effects of using different desired speed distributions for different pedestrian types have also been investigated. The error between the average of the observed and the simulated walking speeds varies between 2.3 and 4.1 percent when dividing pedestrians into different types when the optimal desired speed distributions at the low flow level are used at the high flow level. A sensitivity analysis of some parameters of the social force model in Viswalk has also been performed. Several adjustments of the parameters show that some parameters had great impact of the simulated walking speeds. The final conclusion is that the parameter configuration and how the pedestrians are divided into different types affect the average simulated walking speed.

APA, Harvard, Vancouver, ISO, and other styles

14

Johansson, Sofia, and Sri Vasireddy. "Analysis of Mobility and Traffic Safety with Respect to Changes in Volumes; Case Study: Stockholm, Sweden." Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-177780.

Full text

Abstract:

The growing population and motorization generate more movements. In many cities, the increase of population and motorization is much greater than the development of the capacity of the transportation network. For unprotected road users, the risk of getting in a traffic accident increases and the risk of being more severely injured in an accident. In March 2020, a pandemic was declared because of a Coronavirus. More people started to work/study from home to prevent the virus from spreading by avoiding unnecessary trips, gatherings, and crowded areas. Therefore, travel behaviours have shifted during the pandemic compared to previous years. This project aims to get knowledge of how mobility and traffic accidents are affected by significant shifts of travel flow, predict the effect of traffic accidents based on mobility, and evaluate the risk of travelling on a particular road segment.

Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet

APA, Harvard, Vancouver, ISO, and other styles

15

Deshpande, Vinit Vinod. "Evaluating the Impacts of Transit Signal Priority Strategies on Traffic Flow Characteristics:Case Study along U.S.1, Fairfax County, Virginia." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/31319.

Full text

Abstract:

Transportation engineers and planners worldwide are faced with the challenge of improving transit services in urban areas using low cost means. Transit signal priority is considered to be an effective way to improve transit service reliability and efficiency. In light of the interest in testing and deploying transit signal priority on a major arterial in Northern Virginia, this research focuses on the impacts of transit signal priority in the U.S.1 corridor in Fairfax County in terms of benefits to transit and impacts on other traffic. Using a simulation tool, VISSIM, these impacts were assessed considering a ten second green extension priority strategy. The results of the simulation analysis indicated that the Fairfax Connector buses benefit from the green extension strategy with little to no impact on the other non-transit traffic. Overall, improvements of 3.61% were found for bus service reliability and 2.64% for bus efficiency, while negative impacts were found in the form of increases in queue lengths on side streets by a maximum value of approximately one vehicle. Because this research has provided a foundation for the evaluation of transit signal priority for VDOT and Fairfax County engineers and planners, future research can build upon this effort. Areas identified for future research include the provision of priority for the entire bus route; combination of emergency preemption and transit priority strategies; evaluation of other priority strategies using system- wide priority concepts; and the impacts of priority strategies in monetary terms.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

16

Boucher, Christina Anne. "A study into the efficiency of traffic : flows induced by selfish agents." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=83967.

Full text

Abstract:

We examine the following traffic model. There is a network of users who wish to route traffic to their destinations as quickly as possible. Each edge in the network has a load-dependent function specifying the delay experienced by traffic using that network link. In an optimal routing scheme the total latency incurred by all the network users is minimized. However, when users are free to route traffic according to their own interests the network traffic converges to a selfishly defined traffic assignment which can be more costly than the optimal solution. The following question then arises; how much deterioration in network performance can be caused by this lack of coordination? First, we explore this question by quantifying the efficiency losses inherent in the selfishly defined solution. Second, we focus on designing selfish routing instances that produce optimal network flows. We present, an assortment of results on these topics and suggest some promising new areas of research.

APA, Harvard, Vancouver, ISO, and other styles

17

Павловський, Владислав Олександрович. "Система керування дорожнім рухом у місті." Master's thesis, КПІ ім. Ігоря Сікорського, 2019. https://ela.kpi.ua/handle/123456789/32305.

Full text

Abstract:

Інтенсивне збільшення кількості транспортних засобів у містах України за останні роки призвело до значного перевантаження транспортної мережі, утворення транспортних заторів. Хоча виникнення заторів обумовлено багатьма факторами, значна їх кількість сконцентрована на регульованих перехрестях. Метою даної роботи є підвищення ефективності керування дорожнім рухом у місті. Особлива увага приділяється керуванню світлофорними об’єктами з використанням сучасного апарата нечіткої логіки. Розроблено структуру побудови системи керування дорожнім рухом в місті. Виділено підсистеми реєстрації дорожнього руху, світлофорного регулювання, керування зовнішнім освітленням. В такому випадку система легко модернізується і масштабується. Проведено дослідження транспортного потоку. Побудовано математичну модель нечіткого логічного виведення для гнучкого регулювання тривалості фаз двохфазного світлофорного об’єкта.
In recent years, the intensive increase of vehicles in the cities of Ukraine has led to significant overload of the transport network and formation of traffic jams. Although congestion is caused by many factors, many of them are concentrated at controlled intersections. The purpose of this work is to improve the efficiency of road traffic control in the city. Special attention is paid to the management of traffic light objects using modern apparatus of indistinct logic. The structure of construction of traffic management system in the city has been developed. The subsystems of traffic registration, traffic lights, outdoor lighting control have been highlighted. In this case, the system is easily upgraded and scalable. The study of traffic flow was conducted. The mathematical model of fuzzy inference system for flexible phase duration control of two-phase traffic light object was constructed.

APA, Harvard, Vancouver, ISO, and other styles

18

Mosslemi, Marjan. "Using Metering Signals at Roundabouts with Unbalanced Flows to Improve the Traffic Condition : The Case Study of Kannik Area in Stavanger." Thesis, Linköping University, Department of Science and Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-16429.

Full text

Abstract:

In some roundabouts, just relying on the "right of way" regulations results in long queues forming along the approaches. This usually happens when a roundabout suffers from unbalanced flow patterns (one or two of the approaches convey much heavier traffic compared to the others). There is an idea that signalization of roundabouts can be useful as a countermeasure for such a problem, especially during peak hours. In that case, signal operation can come in many forms, including full-time control, part-time control, or metering. One problem that seems to be facing engineers when signalizing roundabouts is lacking a general set of patterns or guidelines to choose an appropriate form of signalization and apply it efficiently in different situations. There is also a need for a comprehensive review over the available literature concerning signalization of roundabouts. In this thesis, a review of literature regarding signalization of roundabouts is carried out. Moreover, a roundabout in Stavanger with unbalanced traffic flows is studied in order to find an appropriate signalization scenario which can improve the traffic situation. The network is modeled and simulated in AIMSUN.

APA, Harvard, Vancouver, ISO, and other styles

19

Cappiello, Alessandra 1972. "Modeling traffic flow emissions." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/84328.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Godvik, Marte. "On a Traffic Flow Model." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for matematiske fag, 2008. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-2296.

Full text

Abstract:

Paper 1 Electronic version of an article published asJournal of Hyperbolic Differential Equations (JHDE) Year: 2008 Vol: 5 Issue: 1 (March 2008) Page: 45 - 63, DOI:10.1142/S0219891608001428 © [copyright World Scientific Publishing Company] http://ejournals.ebsco.com/Direct.asp?AccessToken=8PUU3U4V0W9F3OY0909K09P3FOXYVWNOW&Show=Object&msid=943592237

APA, Harvard, Vancouver, ISO, and other styles

21

Gebresilassie, Mesele Atsbeha. "Spatio-temporal Traffic Flow Prediction." Thesis, KTH, Geoinformatik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-212323.

Full text

Abstract:

The advancement in computational intelligence and computational power and the explosionof traffic data continues to drive the development and use of Intelligent TransportSystem and smart mobility applications. As one of the fundamental components of IntelligentTransport Systems, traffic flow prediction research has been advancing from theclassical statistical and time-series based techniques to data–driven methods mainly employingdata mining and machine learning algorithms. However, significant number oftraffic flow prediction studies have overlooked the impact of road network topology ontraffic flow. Thus, the main objective of this research is to show that traffic flow predictionproblems are not only affected by temporal trends of flow history, but also by roadnetwork topology by developing prediction methods in the spatio-temporal.In this study, time–series operators and data mining techniques are used by definingfive partially overlapping relative temporal offsets to capture temporal trends in sequencesof non-overlapping history windows defined on stream of historical record of traffic flowdata. To develop prediction models, two sets of modeling approaches based on LinearRegression and Support Vector Machine for Regression are proposed. In the modelingprocess, an orthogonal linear transformation of input data using Principal ComponentAnalysis is employed to avoid any potential problem of multicollinearity and dimensionalitycurse. Moreover, to incorporate the impact of road network topology in thetraffic flow of individual road segments, shortest path network–distance based distancedecay function is used to compute weights of neighboring road segment based on theprinciple of First Law of Geography. Accordingly, (a) Linear Regression on IndividualSensors (LR-IS), (b) Joint Linear Regression on Set of Sensors (JLR), (c) Joint LinearRegression on Set of Sensors with PCA (JLR-PCA) and (d) Spatially Weighted Regressionon Set of Sensors (SWR) models are proposed. To achieve robust non-linear learning,Support Vector Machine for Regression (SVMR) based models are also proposed.Thus, (a) SVMR for Individual Sensors (SVMR-IS), (b) Joint SVMR for Set of Sensors(JSVMR), (c) Joint SVMR for Set of Sensors with PCA (JSVMR-PCA) and (d) SpatiallyWeighted SVMR (SWSVMR) models are proposed. All the models are evaluatedusing the data sets from 2010 IEEE ICDM international contest acquired from TrafficSimulation Framework (TSF) developed based on the NagelSchreckenberg model.Taking the competition’s best solutions as a benchmark, even though different setsof validation data might have been used, based on k–fold cross validation method, withthe exception of SVMR-IS, all the proposed models in this study provide higher predictionaccuracy in terms of RMSE. The models that incorporated all neighboring sensorsdata into the learning process indicate the existence of potential interdependence amonginterconnected roads segments. The spatially weighted model in SVMR (SWSVMR) revealedthat road network topology has clear impact on traffic flow shown by the varyingand improved prediction accuracy of road segments that have more neighbors in a closeproximity. However, the linear regression based models have shown slightly low coefficientof determination indicating to the use of non-linear learning methods. The resultsof this study also imply that the approaches adopted for feature construction in this studyare effective, and the spatial weighting scheme designed is realistic. Hence, road networktopology is an intrinsic characteristic of traffic flow so that prediction models should takeit into consideration.

APA, Harvard, Vancouver, ISO, and other styles

22

Golden, Gaylynn. "Effects of driver characteristics and traffic composition on traffic flow." Master's thesis, This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-10242009-020010/.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Kim, Youngho. "Online traffic flow model applying dynamic flow density relations." [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=964751909.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Yan, Li. "On the traffic flow control system." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B39431174.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Yan, Li, and 顏理. "On the traffic flow control system." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B39431174.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Heller, Mark D. "Behavioral analysis of network flow traffic." Thesis, Monterey, California. Naval Postgraduate School, 2010. http://hdl.handle.net/10945/5108.

Full text

Abstract:

Approved for public release, distribution unlimited
Network Behavior Analysis (NBA) is a technique to enhance network security by passively monitoring aggregate traffic patterns and noting unusual action or departures from normal operations. The analysis is typically performed offline, due to the huge volume of input data, in contrast to conventional intrusion prevention solutions based on deep packet inspection, signature detection, and real-time blocking. After establishing a benchmark for normal traffic, an NBA program monitors network activity and flags unknown, new, or unusual patterns that might indicate the presence of a potential threat. NBA also monitors and records trends in bandwidth and protocol use. Computer users in the Department of Defense (DoD) operational networks may use Hypertext Transport Protocol (HTTP) to stream video from multimedia sites like youtube.com, myspace.com, mtv.com, and blackplanet.com. Such streaming may hog bandwidth, a grave concern, given that increasing amounts of operational data are exchanged over the Global Information Grid, and introduce malicious viruses inadvertently. This thesis develops an NBA solution to identify and estimate the bandwidth usage of HTTP streaming video traffic entirely from flow records such as Cisco's NetFlow data.

APA, Harvard, Vancouver, ISO, and other styles

27

Yu, Tungsheng. "Traffic flow modeling in highway networks." Master's thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-12232009-020154/.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Sestak, Mark R. Carleton University Dissertation Computer Science. "Traffic flow monitoring in PBX networks." Ottawa, 1990.

Find full text

APA, Harvard, Vancouver, ISO, and other styles

29

Långström, Stina, and Emilia Fridsäll. "Optimizing traffic flow on congested roads." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254936.

Full text

Abstract:

Traffic congestion is a common problem in larger cities. Time consuming queues affects both the humans and the environment. This report investigate show to improve the traffic flow in a future scenario where only autonomous vehicles are present. The methodology was to construct traffic networks on routes where congestion is a problem. This was done with three different Stockholm routes. The networks were transformed into graphs and then the maximal flow was calculated by Edmond Karp’s flow algorithm. The result proves that this type of route planning is a concept that can be used in future studies to decrease congestion. This is due to the fact that the flow increase was much larger than both the increase in travelled distance and time.
Trafikstockning är ett vanligt förekommande problem i större städer. Tidskrävande köer påverkar både människan och miljön. I denna rapport studeras hur man kan förbättra trafikflödet i ett framtida scenario där endast automatiserade fordon är tillgängliga. Metoden var att konstruera ett nätverk utav vägar där trängsel är ett problem. Detta gjordes för tre olika rutter i Stockholm. Nätverken transformerades sedan till grafer och det maximala flödet beräknades med hjälp av Edmond Karps flödesalgoritm. Resultatet visar på att denna typ av ruttoptimering skulle kunna användas i framtida studier för att minska trafikstockning i och med att flödesökningen var betydligt större än både ökningen i avstånd och tid.

APA, Harvard, Vancouver, ISO, and other styles

30

Wall, Zach R. "Traffic management and control utilizing a microscopic model of traffic dynamics /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/5922.

Full text

APA, Harvard, Vancouver, ISO, and other styles

31

Reed, Brandon B. "Continuum Traffic Flow at a Highway Interchange." University of Akron / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=akron1196711036.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Wang, Roy J. "Simulation based evaluation on the effects of jaywalking." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 77 p, 2009. http://proquest.umi.com/pqdweb?did=1885755931&sid=1&Fmt=2&clientId=8331&RQT=309&VName=PQD.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Markowski, Michael J. "Modeling behavior in vehicular and pedestrian traffic flow." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 162 p, 2008. http://proquest.umi.com/pqdweb?did=1654493641&sid=2&Fmt=2&clientId=8331&RQT=309&VName=PQD.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Jost, Dominic. "Breakdown and recovery in traffic flow models." Zürich : ETH, Eidgenössische Technische Hochschule Zürich, Dept. of Computer Science, 2002. http://e-collection.ethbib.ethz.ch/show?type=dipl&nr=98.

Full text

APA, Harvard, Vancouver, ISO, and other styles

35

Hung, Yu-Kuan, and 洪郁冠. "A Study on Traffic Safety Parameters under Mixed Traffic Flow." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/29103976758337719089.

Full text

Abstract:

碩士
國立臺灣大學
土木工程學研究所
103
Mixed traffic flow is the most common traffic situation in urban areas in Taiwan. The motorcycles are usually thought to be the source of chaos. The reasons are that the size of motorcycles is small, and they do not have their own lanes, weaving among the hurtling cars and heavy vehicles like a seamstress in search of a seam. The action makes traffic unsafety and without regular rules. In this study, it picks up some traffic safety related parameters, ”Direct”, “Dummy Lane”, “Acceleration Noise” ,and does some adjustment on them in order to make these be calculated by a computer. Also, it discovered that the “Direct” and “Acceleration Noise” can reflect the difference of the amount of motorcycle related accident density of different road designs, the exclusive motorcycle lane. However, comparing the values of these parameters which were output from several different scenarios of the VISSIM simulation experiments. It found that only the “Direct” parameter fit the result mentioned above. The “Dummy Lane” and “Acceleration Noise” can only reflect the traffic flow conditions of different road designs in simulation environment. Above all, the design of the exclusive motorcycle lane make some good influences to the traffic. It exactly prevent the motorcycles from conflict with other vehicles, and reduce the amount of motorcycle related accident density.

APA, Harvard, Vancouver, ISO, and other styles

36

Hsu, Yi-hung, and 許義宏. "A Study on Macroscopic Mixed Traffic Flow Model." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/52193493026151914039.

Full text

Abstract:

碩士
國立成功大學
交通管理學系碩博士班
95
Macroscopic traffic flow models are intended to describe vehicular flows as the movement of fluid, and to establish relationships of traffic flow parameters, such as flow, density, and speed. Traditional traffic flow models view a vehicle as a particle, and assume that vehicles are in a single lane without lane-changing behavior. Most of the studies focused on passenger car, but the components of traffic were not the uniform vehicle, including passenger cars, heavy vehicles, motorcycles, bicycles, etc. The traffic heterogenous characteristics are difficult to be captured in analytical forms. However, macroscopic models are easier to be applied in traffic analysis than microscopic models. The vehicular flows in Taiwan are mixed with heavy vehicles, passenger cars and motorcycles, for example motorcycles ratio is higher than 60% in the cities. The physical size of motorcycle is smaller than car, and it can easily pass through passenger cars. For these reasons, traditional traffic flow models cannot reasonably explain the phenomenon of mixed traffic flow with passing. This study aims at analyzing traffic by vehicle’s occupied area, and uses car-following model to establish macroscopic model. The developed macroscopic models are examined and verified through field data. In this study, the results show that the car-following phenomena between cars is more significant than motorcycles, and space headway can be used to establish one-dimension traffic models. Since car and motorcycle are restricted by road capacity, this study considers characteristics of cars and motorcycles and uses vehicles’ occupied areas to establish the macroscopic vehicular flow model. Through field data, the statistical results show that the area-based concept can be applied to describe mixed vehicular flow behavior. The study mainly establishes speed-density relationship for under-saturation flow conditions, due to insufficient data for congested traffic conditions.

APA, Harvard, Vancouver, ISO, and other styles

37

Sung, Wei-Ting, and 宋威廷. "A study of multilane highway traffic flow models." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/93239070670241699422.

Full text

Abstract:

碩士
國立交通大學
運輸科技與管理學系
100
This study presents a set of traffic flow models that account of operating effects among vehicles on multilane highways. It is known that the driver’s behavior and traffic characteristics on single-lane highways are fairly different from those on multilane ones. Many of the past studies have applied various wave equations to describe such traffic phenomena. This study explores the curve tendency, and their characteristics and associated parameters of each the traffic model that is proposed and calibrated from some freeway segments with different number of travel lanes. The actual traffic data are collected from a number of lane-based VDs along the National Taiwan Freeway. For two freeway segments with different lanes, the data analysis has shown that the rate of change in total capacity is not proportional to that in the number of lanes. When in congestion, however, the rate of increasing in congested flow is larger than that in the number of lanes. Plus, the free flow speed for a specific lane may be affected due to the side friction of traffic streams on the adjacent lanes. This study has modified the free-flow-speed term of the model proposed by Drake, Schofer, and May and developed a new speed-density relationship for multilane highways. The index of Mean Absolutely Percentage Error (MAPE) is used as the measure to check the fitness of each model to the associated actual data. Based on the scale suggested by Lewis in 1982, the MAPE value for each model with varied lanes is less than 10%. Hence, it is truly believed that the proposed traffic flow models can work with high accuracy.

APA, Harvard, Vancouver, ISO, and other styles

38

Ho, Chia Chuan, and 何佳娟. "The study on microscopic mixed traffic flow model." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/95912571958176489451.

Full text

Abstract:

碩士
國立交通大學
運輸科技與管理學系
91
The major goal of traffic simulation is the prediction of traffic flow, which is the basic of traffic management. However, it is not easy to collect real-time traffic flow data. Thus, we adopt microscopic simulation approach for analyzing the traffic maneuvers. We consider the effect of the front vehicles in our model to simulate the inter-lane and intra-lane traffic maneuvers. In addition, we take the turning factor and the effect of front vehicle’s speed in lane changing decision-making rules into consideration. A logic red light traffic simulator is also accomplished for the cases of traffic light stops. This proposed simulation model is implemented in C programming language. This simulation model is calibrated and tested with video-based traffic flow data. Testing results indicate that this simulation model is able to adequately simulate microscopic traffic flow. It concludes that the proposed simulation model and relevant rules are essential for the development of advanced traffic flow detection and management systems and related techniques.

APA, Harvard, Vancouver, ISO, and other styles

39

WANG, CHI-KUN, and 王麒琨. "Traffic Lights Analysis Based on Traffic Flow: A Case Study of Taipei City." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/6shmq8.

Full text

Abstract:

碩士
朝陽科技大學
資訊與通訊系
106
Intelligent transport system is one of the indispensable systems in smart cities. Intelligent transport system is the key to a smooth operation of the city. Many countries have invested a lot of resources in developing intelligent transportation systems. However, Taiwan’s intelligent transport system is still in the preliminary stage. There is no set of feasible mechanisms for how to apply the information returned by the device. This paper proposes a systematic approach to traffic assessment that can be analyzed and judged based on the data collection by the vehicle detector. Base on traffic flow, the relationship between road junctions can be analyzed. Utilizing these analysis results, it is possible to find the better cycle of traffic lights. This paper uses cluster analysis as method of data preprocessing. Cluster analysis can effectively group data based on the relationship between data that can improve the quality of data, and effectively reduce the time consuming of analysis. This paper will divide the city of Taipei into multiple small areas according to the collected data, and analyze the traffic flow patterns of these areas. The result of the analysis will as a consideration for the configuration of traffic lights. The experiment result shows that after more comprehensive considerations, it is possible to reduce the vehicle delay rate at the intersection and reduce the degree of traffic congestion. In addition, through deep learning as a classification model, it is possible to effectively classify intersection congestion levels with simple data without the need for tedious operations.

APA, Harvard, Vancouver, ISO, and other styles

40

Hsu, Yu-Ting, and 許聿廷. "Study on Real-Time Traffic Data Acquisitions and Algorithms for Parameters of Traffic Flow." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/20111557358751113247.

Full text

Abstract:

碩士
國立臺灣大學
土木工程學研究所
92
In order to establish an advanced traffic management system (ATMS), this study proposes a real-time traffic data acquisition system. The framework of system has its basis of taxi fleets as probe vehicles, and combines roadside detectors to collect traffic data from urban network extensively. According to the physical architecture, the study builds the mathematic models of “travel time prediction for road section” and “dynamic OD estimation”. The algorithms are based on generalized least squares (GLS) and extended Kalman filter (EKF) respectively. Through the prediction model, the traffic flows at various conditions are predicted to support decision-making of traffic control and management. To verify the models, for travel time prediction, this study analyzes the prediction results of grid network simulation from the Paramics, which is a traffic simulation package, and evaluates prediction capability by indices of precision, robustness and stability. The model proves a good prediction resulting in data calibration and processing. For the dynamic OD estimation, the study estimates traffic volume from predicted OD flows, which generates the mean error is within 10%. Accordingly, it concludes that the model is reasonable. Also, considering the representation of probe vehicles in the traffic flow, the model has good prediction capability, when the proportion of probe vehicles is above 5% of all vehicles.

APA, Harvard, Vancouver, ISO, and other styles

41

CHEN, ZHI-WEI, and 陳志偉. "A simulation study of mixed traffic flow at roundabout." Thesis, 1987. http://ndltd.ncl.edu.tw/handle/27787505765513499160.

Full text

APA, Harvard, Vancouver, ISO, and other styles

42

Tseng, Hsiang-Hsin, and 曾祥信. "A Study of Applicability of Flow-based Internet Traffic Classification." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/98504842472728821970.

Full text

Abstract:

碩士
臺灣大學
資訊工程學研究所
98
The classification of IP flows according to the applications that generated them is at the basis of any modern network management platform. It has become a challenge in the last decade since many applications use tricky ways to avoid being easily recognized. Classical techniques such as port-based detection are rapidly becoming ineffective. Many reputable research groups have published several interesting papers on traffic classification, proposing mechanisms of different nature. However, it is our opinion that some factors in real-world network environments would affect the effectiveness of these classification mechanisms. In this paper we implement a flow-based Internet traffic classifier and conduct an experiment to measure its performance dealing with real-world data traces. Even though the classification method is based on the work in the past, our contribution is to provide insights into flow-based traffic classification technique and to analyze the applicability of it. Our results expose several real-world issues while applying flow-based classification; some can be resolved by the mechanisms we propose, and some still need to be researched in further work. We also present the impact of flow sampling to the technique. Our results show that the effectiveness of flow-based traffic classification is limited in a certain range of sampling intervals.

APA, Harvard, Vancouver, ISO, and other styles

43

Jou, Tyh-Jong, and 周志忠. "The Study of Numerical Methods for Traffic Flow Continuum Models." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/37890263968939741914.

Full text

Abstract:

碩士
國立交通大學
交通運輸研究所
85
Macroscopic traffic flow continuum models are composed of single or systems of partial difference equations (PDEs) with suitable initial and boundary conditions which describe various traffic phenomena and road geometry. These models have provided a useful tool with which to test and assess road and traffic control plans. Since the analytical solutions of traffic flow continuum models are difficult to be solved. How to find an approximate and efficient numerical solution becomes an important course. This study takes aim at the numerical finite difference methods of traffic flow continuum models. At first, there are seven methods of explicit finite difference schemes and two methods of implicit schemes used to solve the first order linear continuum models, and compare the errors between exact solution and numerical solutions of these methods. In these results, there are three better algorithms, including Lax-F、Lax-W and Leapfrog schemes, used to simulate the quasilinear continuum models, and the Lax-F scheme can get a more reasonable solution. In the process of numerical computation, we found that every explicit finite difference methods must satisfy the CFL condition to ensure the stability and convergence. This condition requires the ratio of the mesh in space and the mesh in time must satisfy some constrains, and this makes the computation lack of efficiency. Therefore, this study based on the CFL condition develops an adaptive finite difference scheme to solve the LWR model more efficiently. This adaptive scheme can determine automatically the nest suitable time mesh size from the characteristic curve of every grid points in this time, and it can converge to a stable solution. In the numerical test, the Lax method and adaptive Lax method are used to solve the LWR model with different initial and boundary conditions. The simulation results show us that the adaptive Lax method is more efficiency than the Lax method.

APA, Harvard, Vancouver, ISO, and other styles

44

林永輝. "Study of the traffic flow detection through video image processing." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/72602413029946348470.

Full text

Abstract:

碩士
國立彰化師範大學
機電工程學系
96
As the number of sources of traffic increases and there are more and more cars on the roads, traffic safety and traffic congestion have become important issues. Using video frame grabbing techniques at intersections the information of traffic volumes will help us to determine traffic signal changes length. It offers solutions to relieve traffic jams and prevents traffic accidents.This paper deals with the traffic signal control. WebCam cameras are set at intersections to acquire vehicle image data, by performing image processing,such as background building, image subtraction algorithm, noise removing,image shadow processing, binary, chain code calculation, and tag counting.According to the above car recognition skills, the overview of car flow and the road conditions could be detected, which enable the traffic control system to determine the traffic signal changes.

APA, Harvard, Vancouver, ISO, and other styles

45

Chang, Ting-Yu, and 張庭瑜. "A Study of Traffic Flow Models on Freeway Work Zones." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/48398563564061079929.

Full text

Abstract:

碩士
淡江大學
運輸管理學系
88
The purpose of this study is to compare traditional high-order traffic flow models applied on freeway work zones and build a modified methodology. A good traffic flow model is contributive to control traffic states, especially in the work zones. When the lane dropped, a proper control could not only minimize the total delay, but also diminish the effectiveness of work zones. For this reason, this study focusing on freeway work zones used high-order continuum models of Payne and Michalopoulos as base and furthered to consider the characteristic of work zones including the geometry condition and the drivers’ choice behavior. According to the investigated data that was using for calibrating the models we found the more the distance the drivers approached to the work zone, the more the speed decreased. Then, we used the two-stage method to identify the parameters. The First stage was to calibrate the basic characters of the traffic flow parameters and the second stage was to search the better parameter sets by minimizing the differences between the real data and model outputs. Finally, we compared the modified models before and after using the results of statistic validation, it suggested that the modified models were more accurate.

APA, Harvard, Vancouver, ISO, and other styles

46

Song, Chong Chul. "Simulation study of traffic flow at a three way intersection." Thesis, 1988. http://hdl.handle.net/10945/23117.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Chen, Che-An, and 陳哲安. "A Study of Traffic Flow Prediction Using LSTM and GRU." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/9f3tp7.

Full text

Abstract:

碩士
國立政治大學
資訊科學系
107
In recent years, with the promotion of smart cities in each county, the issue of how to resolve the problem of traffic chaos has drawn much attention. If we can accurately predict the traffic flow, then we can alleviate the traffic congestion more effectively. ARIMA (Autoregressive Integrated Moving Average model) were used to predict traffic flow. As the deep learning method has a breakthrough in many other fields, more and more studies propose to use deep learning models to solve real-world problems, and the results approve that both LSTM (Long Short-Term Memory) and GRU (Gated Recurrent Units) models have excellent performance in traffic flow prediction. The proposed method is going to use both "normal traffic flow data" and "predictable sporadic activity data." As to the "normal traffic flow data," we use the "Vehicle Detector (VD) Data" given by the Taipei City Government Information Open Platform. On the other side, the traffic is also vulnerable to predictable sporadic activities, such as citywide carnival and festival, large-scale concerts, weather, etc. At this part, we code web crawler for websites of the ticket office, tourist information, news information, Central Weather Bureau, etc. These training data is fed into the LSTM and GRU deep learning models. We then use Adam Optimizer to optimize the models. The implementations of both LSTM and GRU models are based on TensorFlow of Google. Finally, we use MAE (Mean Absolute Error) and MAPE (Mean Absolute Percentage Error) to evaluate the urban traffic flow prediction accuracy of both LSTM and GRU models.

APA, Harvard, Vancouver, ISO, and other styles

48

Hsu, Cheng-Sung, and 許晟松. "A Study of Roundabout Metering Controlled Methodunder Mixed Traffic Flow." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/qr469q.

Full text

Abstract:

碩士
國立臺灣大學
土木工程學研究所
107
Roundabout has been popular in European countries because it provides more safety and efficient functions at low and medium flow rates. In recent years, the US has begun to promote road diet concept and build more roundabout; Japan also started to install this intersection type in suburban area. It can be seen that roundabout has become one of the recent trends in traffic design in the global. However, it’s harder to develop roundabout in Taiwan due to the serious mixed traffic flow situation and high percent mode share to private vehicle. In this study, the implement of roundabout metering strategy is set up for solving the intersection with higher peak hour factor and is hoped to increase the overall capacity. Also, it reduces vehicle delay and becomes much safer than signalized junction in off-peak conditions. This implement helps expand the applicability for roundabout. This research uses VisVAP to explore roundabout metering method by occupancy strategy. The goal is to creates larger gaps for downstream entrant vehicles to decrease the overall vehicle delay and queue length with limited negative impact on the main roads. This study also discusses the minimum blank time and minimum metering time to appropriate balance the impact between main road and the downstream entrant. The simulation model is proved to have credibility and reliability after rigorous model calibration and validation. The three scenarios which were metering roundabout, unsignalized roundabout and normal signalized junction were simulated in different demand ratio, mixed traffic flow ratio and turning ratio composition for analysis. By analyzing the average vehicle delay and maximum queue length performances with roundabout metering strategy, the results show that roundabout metering can significantly reduce overall vehicle delay and queue length under every mixed traffic ratio combination and only has slightly negative effect on main road.

APA, Harvard, Vancouver, ISO, and other styles

49

王郁凱. "A Study on Traffic Flow Model of Motorcycle Exclusive Lane." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/69231808840049932768.

Full text

Abstract:

碩士
國立交通大學
運輸科技與管理學系
94
In Taiwan, most traffic flow is mixed automobiles and motorcycles flow. This situation influences the road capacity, traffic flow order and safety. To solve this problem, some reviewed literature emphasizes setting up the motorcycle exclusive lane by traffic engineering method, could improve traffic order and safety effectively. However, motorcycle traffic flow study is quite scarce abroad. In Taiwan, though there are a lot of studies of motorcycle traffic flow, they are aimed to mixed traffic flow rather than motorcycles exclusively. As a result, the microscopic motorcycle traffic flow study is incomplete. This study is attempted to structure and verify microscopic motorcycle traffic flow models on motorcycle exclusive lane by carrying on the investigation and analysis with the real traffic flow materials on the section road. This study is based on car-following theory, lane-changing theory and fuzzy theory. Motorcycle car following and overtaking model were built with literature review, statistics analytic approach, video investigation method and artificial intelligence algorithms etc. Car following model was built by the fuzzy inference approach, combining artificial neural network and genetic algorithm, and further compare the quality of them. Overtaking model was built by analyzing the characteristics of the angle of overtaking, and then setting up overtaking decision procedure and criterions for describing the motorcycle traffic flow of the motorcycle exclusive lane completely. As a result, this study results could serve as the basis of improving the motorcycle traffic planning and design, and control.

APA, Harvard, Vancouver, ISO, and other styles

50

SHEN, YEN-HUNG, and 沈彥宏. "A Study on Microscopic Traffic Flow Model of Rural Highways." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/12934864200047436414.

Full text

Abstract:

碩士
國立交通大學
運輸科技與管理學系
94
As the traffic jam in Taiwan getting worse with the fast growth to the amount of the vehicles in Taiwan, it is to hard to resolve the traffic system. Specifically, rural highway is the mainstream road system in Taiwan, and because it has very complex characters, the aim of this study is to know the characters. Based on car-following theory, microscopic traffic flow theory, kinematics theorem, fuzzy theory, and behavioral threshold model, this study is proposed a microscopic traffic flow model, incorporating the car-following threshold and lane-changing models on rural highways. The car following threshold model is developed by classifying the driver risk factor based on GM Model. This study is also proposed a modified lane changing angle and acceleration models considering the lead car difference between car and bus by video recording data as well. The last part is to propose a lane changing rule based on the proceeding lane changing angel and acceleration models. This study result promotes the road administrators to identify and validate the traffic control system or mange the system on rural highways.

APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic 'Study of traffic flow'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles