WorldWideScience

Sample records for channel traffic requires

  1. Camouflaging Timing Channels in Web Traffic

    OpenAIRE

    Sellke, Sarah H; Wang, Chih-Chun; Bagchi, Saurabh; Shroff, Ness B.

    2009-01-01

    Web traffic accounts for more than half of Internet traffic today. Camouflaging covert timing channels in Web traffic would be advantageous for concealment. In this paper, we investigate the possibility of disguising network covert timing channels as HTTP traffic to avoid detection. Extensive research has shown that Internet traffic, including HTTP traffic, exhibits self-similarity and long range persistence. Existing covert timing channels that mimic i.i.d. legitimate traffic cannot imitate ...

  2. MODELING OF VEHICULAR STEERING EFFICIENCY IN TRAFFIC DIRECTION MOTION CHANNEL

    OpenAIRE

    V. A. Ganai; S. A. O. Diab Abdullah

    2011-01-01

    The paper formulates and solves an actual problem pertaining to vehicular steering efficiency in traffic direction motion channel. Models of operator-drivers with low, medium and high rates in motivational perception of road conditions and also a model for controlling a traffic direction motion have been taken into ccount in the paper.  Modeling has been done by using MATLAB.

  3. MODELING OF VEHICULAR STEERING EFFICIENCY IN TRAFFIC DIRECTION MOTION CHANNEL

    Directory of Open Access Journals (Sweden)

    V. A. Ganai

    2011-01-01

    Full Text Available The paper formulates and solves an actual problem pertaining to vehicular steering efficiency in traffic direction motion channel. Models of operator-drivers with low, medium and high rates in motivational perception of road conditions and also a model for controlling a traffic direction motion have been taken into ccount in the paper.  Modeling has been done by using MATLAB.

  4. Functional Requirements to Support Traffic Organization Service

    Directory of Open Access Journals (Sweden)

    Jung Sik Jeong

    2013-03-01

    Full Text Available In the era of e-Navigation, the future VTS is anticipated to play an important role on the enhancement of maritime safety and the efficiency of maritime transport as a key stakeholder of e-Navigation. The VTS services need the advanced Traffic Organization Service(TOS. In this paper, the VTS functions for TOS is revisited from the reports of IMO e-Navigation Correspondence Group and IALA VTS Committee. In Korea, the research activities to enhance the existing VTS functions have been conducted. In terms of TOS, some VTS functions have been developed. In conclusion, all the past traffic data and real-time ship data are required to provide the advanced TOS. For this, the advanced functions to support TOS should be implemented on VTS console.

  5. Length Requirement of Self-Similar Network Traffic

    Institute of Scientific and Technical Information of China (English)

    RAOYunhua; XUZhongyang; LIUZhenglin

    2004-01-01

    It is important to study the second-order character of self-similar network traffic in performance evaluation. Especially in real-time applications, traffic autocorrelation is a useful analysis tool, so how to estimate it quickly and reliably is a significant problem. In this paper,we studied the estimation and evaluation of self-similar network traffic autocorrelation structure. With the model of Fractional Gaussian noise (FGN) process, we obtained a simple variance expression of estimated autocorrelation,which is the function of Hurst parameter (H) and traffic data length. The relationship among Hurst parameter, accuracy of the estimated autocorrelation and required data length of self-similar traffic shows that the accuracy of estimated autocorrelation decreases with the increasing Hurst parameter and with the decreasing data length too. But over-long sampled data could not improve the accuracy of estimated autocorrelation remarkably. Furthermore, a sharp variety of accuracy is discovered between H > 0.75 and H < 0.75. It is a very interesting phenomenon that had not been reported before. This shows that Hurst parameter could reflect the second-order character of selfsimilarity, but it is not enough to capture all the traffic features. Experiments, which were performed with synthetical FGN traffics, confirmed the validity of our results.It can also be a reference in estimating the autocorrelation function of other self-similar processes.

  6. Traffic

    International Nuclear Information System (INIS)

    This chapter deals with passenger and freight traffic, public and private transportation, traffic related environmental impacts, future developments, traffic indicators, regional traffic planning, health costs due to road traffic related air pollution, noise pollution, measures and regulations for traffic control and fuels for traffic. In particular energy consumption, energy efficiency, pollutant emissions ( CO2, SO2, NOx, HC, CO, N2O, NH3 and particulates) and environmental effects of the different types of traffic and different types of fuels are compared and studied. Legal regulations and measures for an effective traffic control are discussed. (a.n.)

  7. Pyridoxine requirements of channel catfish.

    Science.gov (United States)

    Andrews, J W; Murai, T

    1979-04-01

    In 20 and 12 week feeding trials, channel catfish fingerlings were fed purified diets containing five levels (0, 5, 10, 20, and 30 mg/kg) and six levels (0, 1, 2, 5, 10, and 20 mg/kg) of supplemental pyridoxine hydrochloride. Fish fed unsupplemented diets (pyridoxine content of 1.2 mg/kg) were characterized by anoxeria, nervous disorders, tetany, greenish-blue body coloration, and eventual mortality. Anemia, which has been reported in pyridoxine deficient salmonids, was not observed in pyridoxine deficient catfish. However, a microcytic, normochromic anemia was observed in groups fed high dietary levels of pyridoxine (20 mg/kg or greater). The dietary pyridoxine level required for maximal growth was approximately 3 mg/kg of diet. All other deficiency signs were prevented by 2.2 mg/kg of diet. PMID:430257

  8. A virtual channel network-on-chip for GT and BE traffic

    OpenAIRE

    Kavaldjiev, Nikolay; Smit, Gerard J.M.; Jansen, Pierre G.; Wolkotte, Pascal T.

    2005-01-01

    This paper presents an on-chip network for a run-time reconfigurable System-on-Chip. The network uses packet-switching with virtual channels. It can provide guaranteed services as well as best effort services. The guaranteed services are based on virtual channel allocation, in contrast to other on-chip networks where guarantees are provided by time-division multiplexing. The network is particularly suitable for systems in which the traffic is dominated by streams. We model the data traffic in...

  9. Using Uncensored Communication Channels to Divert Spam Traffic

    OpenAIRE

    Benjamin Chiao; Jeffrey MacKie-Mason

    2006-01-01

    We offer a microeconomic model of the two-sided market for the dominant form of spam: bulk, unsolicited, and commercial advertising email. We adopt an incentive-centered design approach to develop a simple, feasible improvement to the current email system using an uncensored communication channel. Such a channel could be an email folder or account, to which properly tagged commercial solicitations are routed. We characterize the circumstances under which spammers would voluntarily move much o...

  10. The Performance Analysis of Traffic Channel Coding in Digital Trunking System

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The encoding and decoding processes of traffic channel in digital trunking system are studied. On the basis of computer simulation, the BER (bit error ratio) with different RCPC decoding step is analyzed. As a result, the optimal RCPC decoding step is provided, which gives essential theoretical evidences for the implementation of digital trunking system.

  11. Performance Analysis of Spectrum Handoff for Cognitive Radio Ad Hoc Networks without Common Control Channel under Homogeneous Primary Traffic

    CERN Document Server

    Song, Yi

    2011-01-01

    Cognitive radio (CR) technology is regarded as a promising solution to the spectrum scarcity problem. Due to the spectrum varying nature of CR networks, unlicensed users are required to perform spectrum handoffs when licensed users reuse the spectrum. In this paper, we study the performance of the spectrum handoff process in a CR ad hoc network under homogeneous primary traffic. We propose a novel three dimensional discrete-time Markov chain to characterize the process of spectrum handoffs and analyze the performance of unlicensed users. Since in real CR networks, a dedicated common control channel is not practical, in our model, we implement a network coordination scheme where no dedicated common control channel is needed. Moreover, in wireless communications, collisions among simultaneous transmissions cannot be immediately detected and the whole collided packets need to be retransmitted, which greatly affects the network performance. With this observation, we also consider the retransmissions of the collid...

  12. What is required to guarantee data quality for regional traffic management. Implementation of traffic data quality management in the Middle Netherlands

    NARCIS (Netherlands)

    Seelen, P.A.G.; Vrancken, J.L.M.

    2013-01-01

    VERDER, a partnership of different governmental organizations in the Middle Netherlands, initiated different projects for regional traffic management to better use existing road capacity and safeguard mobility in the Middle Netherlands. This active form of traffic management requires traffic data wi

  13. A Prediction Packetizing Scheme for Reducing Channel Traffic in Transaction-Level Hardware/Software Co-Emulation

    CERN Document Server

    Lee, Jae-Gon; Ahn, Ki-Yong; Lee, Sang-Heon; Kyung, Chong-Min

    2011-01-01

    This paper presents a scheme for efficient channel usage between simulator and accelerator where the accelerator models some RTL sub-blocks in the accelerator-based hardware/software co-simulation while the simulator runs transaction-level model of the remaining part of the whole chip being verified. With conventional simulation accelerator, evaluations of simulator and accelerator alternate at every valid simulation time, which results in poor simulation performance due to startup overhead of simulator-accelerator channel access. The startup overhead can be reduced by merging multiple transactions on the channel into a single burst traffic. We propose a predictive packetizing scheme for reducing channel traffic by merging as many transactions into a burst traffic as possible based on 'prediction and rollback.' Under ideal condition with 100% prediction accuracy, the proposed method shows a performance gain of 1500% compared to the conventional one.

  14. TRP channels and traffic-related environmental pollution-induced pulmonary disease.

    Science.gov (United States)

    Akopian, Armen N; Fanick, E Robert; Brooks, Edward G

    2016-05-01

    Environmental pollutant exposures are major risk factors for adverse health outcomes, with increased morbidity and mortality in humans. Diesel exhaust (DE) is one of the major harmful components of traffic-related air pollution. Exposure to DE affects several physiological systems, including the airways, and pulmonary diseases are increased in highly populated urban areas. Hence, there are urgent needs to (1) create newer and lesser polluting fuels, (2) improve exhaust aftertreatments and reduce emissions, and (3) understand mechanisms of actions for toxic effects of both conventional and cleaner diesel fuels on the lungs. These steps could aid the development of diagnostics and interventions to prevent the negative impact of traffic-related air pollution on the pulmonary system. Exhaust from conventional, and to a lesser extent, clean fuels, contains particulate matter (PM) and more than 400 additional chemical constituents. The major toxic constituents are nitrogen oxides (NOx) and polycyclic aromatic hydrocarbons (PAHs). PM and PAHs could potentially act via transient receptor potential (TRP) channels. In this review, we will first discuss the associations between DE from conventional as well as clean fuel technologies and acute and chronic airway inflammation. We will then review possible activation and/or potentiation of TRP vanilloid type 1 (TRPV1) and ankyrin 1 (TRPA1) channels by PM and PAHs. Finally, we will discuss and summarize recent findings on the mechanisms whereby TRPs could control the link between DE and airway inflammation, which is a primary determinant leading to pulmonary disease. PMID:26837756

  15. TRP channels and traffic-related environmental pollution-induced pulmonary disease

    Science.gov (United States)

    Akopian, Armen N.; Fanick, E. Robert

    2016-01-01

    Environmental pollutant exposures are major risk factors for adverse health outcomes, with increased morbidity and mortality in humans. Diesel exhaust (DE) is one of the major harmful components of traffic-related air pollution. Exposure to DE affects several physiological systems, including the airways, and pulmonary diseases are increased in highly populated urban areas. Hence, there are urgent needs to (1) create newer and lesser polluting fuels, (2) improve exhaust aftertreatments and reduce emissions, and (3) understand mechanisms of actions for toxic effects of both conventional and cleaner diesel fuels on the lungs. These steps could aid the development of diagnostics and interventions to prevent the negative impact of traffic-related air pollution on the pulmonary system. Exhaust from conventional, and to a lesser extent, clean fuels, contains particulate matter (PM) and more than 400 additional chemical constituents. The major toxic constituents are nitrogen oxides (NOx) and polycyclic aromatic hydrocarbons (PAHs). PM and PAHs could potentially act via transient receptor potential (TRP) channels. In this review, we will first discuss the associations between DE from conventional as well as clean fuel technologies and acute and chronic airway inflammation. We will then review possible activation and/or potentiation of TRP vanilloid type 1 (TRPV1) and ankyrin 1 (TRPA1) channels by PM and PAHs. Finally, we will discuss and summarize recent findings on the mechanisms whereby TRPs could control the link between DE and airway inflammation, which is a primary determinant leading to pulmonary disease. PMID:26837756

  16. TRAFFIC CHANNEL SIR ESTIMATION BASED ON REVERSE PILOT CHANNEL IN cdma2000

    Institute of Scientific and Technical Information of China (English)

    Zhou Hua Yang Dacheng

    2004-01-01

    Signal-to-Interference Ratio(SIR) is a very important metric of communication link quality. For wireless cellular systems, several control mechanisms, such as power control mechanisms, rate control mechanisms, and allocation of radio resource, are based on SIR estimation.In previous researches, most of researchers concentrated on WCDMA systems, in which pilot symbol is time-multiplexed with data symbol; the method developed in this case is not feasible for cdma2000 systems where pilot symbol is code-multiplexed with data symbol. This paper first develops the SIR estimators based on the reverse pilot channel and then derives the approximate analytic expression for its Mean Squared Error (MSE) function, the accuracy of which is validated through simulation. It is shown that the MSE of the new SIR estimator is significantly smaller than that of other widely used SIR estimators, especially in low SIR case. Finally, the estimate quality of the proposed method is further improved by long-termly averaging the sample interference.

  17. Entanglement required in achieving entanglement-assisted channel capacities

    OpenAIRE

    Bowen, Garry

    2002-01-01

    Entanglement shared between the two ends of a quantum communication channel has been shown to be a useful resource in increasing both the quantum and classical capacities for these channels. The entanglement-assisted capacities were derived assuming an unlimited amount of shared entanglement per channel use. In this paper, bounds are derived on the minimum amount of entanglement required per use of a channel, in order to asymptotically achieve the capacity. This is achieved by introducing a c...

  18. Protection Over Asymmetric Channels, S-MATE: Secure Multipath Adaptive Traffic Engineering

    OpenAIRE

    Aly, Salah A.; Ansari, Nirwan; Poor, H. Vincent; Walid, Anwar I.

    2010-01-01

    Several approaches have been proposed to the problem of provisioning traffic engineering between core network nodes in Internet Service Provider (ISP) networks. Such approaches aim to minimize network delay, increase capacity, and enhance security services between two core (relay) network nodes, an ingress node and an egress node. MATE (Multipath Adaptive Traffic Engineering) has been proposed for multipath adaptive traffic engineering between an ingress node (source) and an egress node (dest...

  19. Analysis of Operational Hazards and Safety Requirements for Traffic Aware Strategic Aircrew Requests (TASAR)

    Science.gov (United States)

    Koczo, Stefan, Jr.

    2013-01-01

    Safety analyses of the Traffic Aware Strategic Aircrew Requests (TASAR) Electronic Flight Bag (EFB) application are provided to establish its Failure Effects Classification which affects certification and operational approval requirements. TASAR was developed by NASA Langley Research Center to offer flight path improvement opportunities to the pilot during flight for operational benefits (e.g., reduced fuel, flight time). TASAR, using own-ship and network-enabled information concerning the flight and its environment, including weather and Air Traffic Control (ATC) system constraints, provides recommended improvements to the flight trajectory that the pilot can choose to request via Change Requests to ATC for revised clearance. This study reviews the Change Request process of requesting updates to the current clearance, examines the intended function of TASAR, and utilizes two safety assessment methods to establish the Failure Effects Classification of TASAR. Considerable attention has been given in this report to the identification of operational hazards potentially associated with TASAR.

  20. Spatial resolution requirements for traffic-related air pollutant exposure evaluations

    Science.gov (United States)

    Batterman, Stuart; Chambliss, Sarah; Isakov, Vlad

    2014-09-01

    Vehicle emissions represent one of the most important air pollution sources in most urban areas, and elevated concentrations of pollutants found near major roads have been associated with many adverse health impacts. To understand these impacts, exposure estimates should reflect the spatial and temporal patterns observed for traffic-related air pollutants. This paper evaluates the spatial resolution and zonal systems required to estimate accurately intraurban and near-road exposures of traffic-related air pollutants. The analyses use the detailed information assembled for a large (800 km2) area centered on Detroit, Michigan, USA. Concentrations of nitrogen oxides (NOx) due to vehicle emissions were estimated using hourly traffic volumes and speeds on 9700 links representing all but minor roads in the city, the MOVES2010 emission model, the RLINE dispersion model, local meteorological data, a temporal resolution of 1 h, and spatial resolution as low as 10 m. Model estimates were joined with the corresponding shape files to estimate residential exposures for 700,000 individuals at property parcel, census block, census tract, and ZIP code levels. We evaluate joining methods, the spatial resolution needed to meet specific error criteria, and the extent of exposure misclassification. To portray traffic-related air pollutant exposure, raster or inverse distance-weighted interpolations are superior to nearest neighbor approaches, and interpolations between receptors and points of interest should not exceed about 40 m near major roads, and 100 m at larger distances. For census tracts and ZIP codes, average exposures are overestimated since few individuals live very near major roads, the range of concentrations is compressed, most exposures are misclassified, and high concentrations near roads are entirely omitted. While smaller zones improve performance considerably, even block-level data can misclassify many individuals. To estimate exposures and impacts of traffic

  1. BER and FER Prediction of Control and Traffic Channels for a GSM type of interface

    DEFF Research Database (Denmark)

    Wigard, Jeroen; Nielsen, Thomas Toftegaard; Michaelsen, Per Henrik; Mogensen, Preben Elgaard

    1998-01-01

    network simulator, but without having to simulate every single link, since this would be to time consuming. In this paper a method is presented to find the BER and FER from the signal to interference (C/I) values for a GSM type of air-interface, which can be used for integration of link aspects in a...... network simulator. The accuracy is within 0.2 dB in case of the BER and 0.5 for the FER. Both traffic and control channels are studied and the method is independent of hopping sequences and speed...

  2. Performance analysis of multi-channel and multi-traffic on wireless communication networks

    CERN Document Server

    Yue, Wuyi

    2007-01-01

    List of Figures. List of Tables. Preface. Acknowledgments. 1: Introduction. 1. Overview of Multiple Access Communication Networks. 2. Packet Communication Networks 3. Wireless Communication Networks. 4. Multiple Access Protocols 5. Mobile Packet Radio Networks with Random Access Protocols. 6. Multichannel Networks with Random Access Protocols. 7. Multi-Hop Networks with Random Access Protocols. 8. Channel Assignment Schemes in Cellular Mobile Networks. 9. Performance Analysis of Wireless Communication Networks. 10. System Models and Performance Analyses in the Book. Part I: Multichannel and Mu

  3. Kir6.2△C26 Channel Traffics to Plasma Membrane by Constitutive Exocytosis

    Institute of Scientific and Technical Information of China (English)

    Ping ZHAO; Wei LI; Yong-Ming DONG; Dan ZHU; An-Lian QU; Tao XU; Zheng-Xing WU

    2006-01-01

    Adenosine triphosphate (ATP)-sensitive K+ (KATP) channels regulate many cellular functions by coupling the metabolic state of the cell to the changes in membrane potential. Truncation of C-terminal 26 amino acid residues of Kir6.2 protein (Kir6.2△C26) deletes its endoplasmic reticulum retention signal, allowing functional expression of Kir6.2 in the absence of sulfonylurea receptor subunit. pEGFP-Kir6.2△C26 and pKir6.2△C26-IRES2-EGFP expression plasmids were constructed and transfected into HEK293 cells. We identified that Kir6.2△C26 was localized on the plasma membrane and trafficked to the plasmalemma by means of constitutive exocytosis of Kir6.2△C26 transport vesicles, using epi-fluorescence and total internal reflection fluorescence microscopy. Our electrophysiological data showed that Kir6.2△C26 alone expressed KATP currents, whereas EGFP-Kir6.2△C26 fusion protein displayed no KATP channel activity.

  4. Pannexin2 oligomers localize into endosomal vesicles in mammalian cells while Pannexin1 channels traffic to the plasma membrane

    Directory of Open Access Journals (Sweden)

    Daniela eBoassa

    2015-02-01

    Full Text Available Pannexin2 (Panx2 is the largest of three members of the pannexin proteins. Pannexins are topologically related to connexins and innexins, but serve different functional roles than forming gap junctions. We previously showed that pannexins form oligomeric channels but unlike connexins and innexins, they form only single membrane channels. High levels of Panx2 mRNA and protein in the Central Nervous System (CNS have been documented. Whereas Pannexin1 (Panx1 is fairly ubiquitous and Pannexin3 (Panx3 is found in skin and connective tissue, both are fully glycosylated, traffic to the plasma membrane and have functions correlated with extracellular ATP release. Here, we describe trafficking and subcellular localizations of exogenous Panx2 and Panx1 protein expression in MDCK, HeLa and HEK293T cells as well as endogenous Panx1 and Panx2 patterns in the CNS. Panx2 was found in intracellular localizations, was partially N-glycosylated, and localizations were non-overlapping with Panx1. Confocal images of hippocampal sections immunolabeled for the astrocytic protein GFAP, Panx1 and Panx2 demonstrated that the two isoforms, Panx1 and Panx2, localized at different subcellular compartments in both astrocytes and neurons. Using recombinant fusions of Panx2 with appended genetic tags developed for correlated light and electron microscopy and then expressed in different cell lines, we determined that Panx2 is localized in the membrane of intracellular vesicles and not in the endoplasmic reticulum as initially indicated by calnexin colocalization experiments. Dual immunofluorescence imaging with protein markers for specific vesicle compartments showed that Panx2 vesicles are early endosomal in origin. In electron tomographic volumes, cross-sections of these vesicles displayed fine structural details and close proximity to actin filaments. Thus, pannexins expressed at different subcellular compartments likely exert distinct functional roles, particularly in the

  5. TRANSIMS traffic flow characteristics

    OpenAIRE

    Nagel, Kai; Stretz, Paula; Pieck, Martin; Donnelly, Rick; Barrett, Christopher L.

    1997-01-01

    Knowledge of fundamental traffic flow characteristics of traffic simulation models is an essential requirement when using these models for the planning, design, and operation of transportation systems. In this paper we discuss the following: a description of how features relevant to traffic flow are currently under implementation in the TRANSIMS microsimulation, a proposition for standardized traffic flow tests for traffic simulation models, and the results of these tests for two different ve...

  6. Naive T lymphocytes traffic to inflamed central nervous system, but require antigen recognition for activation

    DEFF Research Database (Denmark)

    Krakowski, M L; Owens, T

    2000-01-01

    Organ-specific autoimmune diseases may be induced by infiltration of the target tissue by CD4(+) T cells with specificity for self antigen(s). As disease progresses, T cells of other specificities appear in the tissue. Traffic of naive, antigen-inexperienced T cells to target tissues has not been...

  7. TRAFFIC OFFLOADING IMPACT ON THE PERFORMANCE OF CHANNEL-AWARE/QOS-AWARE SCHEDULING ALGORITHMS FOR VIDEO-APPLICATIONS OVER LTE-A HETNETS USING CARRIER AGGREGATION

    Directory of Open Access Journals (Sweden)

    Najem N. Sirhan

    2015-09-01

    Full Text Available Long Term Evolution (LTE is defined by the Third Generation Partnership Project (3GPP standards as Release 8/9. The LTE supports at max 20 MHz channel bandwidth for a carrier. The number of LTE users and their applications are increasing, which increases the demand on the system BW. A new feature of the LTE-Advanced (LTE-A which is defined in the 3GPP standards as Release 10/11 is called Carrier Aggregation (CA, this feature allows the network to aggregate more carriers in-order to provide a higher bandwidth. Carrier Aggregation has three main cases: Intra-band contiguous, Intra-band non-contiguous, Inter-band contiguous. In addition to the Carrier Aggregation feature, LTE-A supports Heterogeneous Networks (HetNets. HetNets consists of a mix of macro-cells, remote radio heads, and low power nodes such as pico-cells, and femto-cells. HetNets allow cellular network operators to support higher data traffic by offloading it to a smaller cells such as femto-cells. The aim of this paper is to evaluate the Quality of Service (QoS performance of the Modified Largest Weighted Delay First (MLWDF, the Exponential Rule (Exp-Rule, and the Logarithmic Rule (Log-Rule scheduling algorithms while offloading 50% of the macro-cell's traffic to five femto-cells, 100% of the macro-cell's traffic to five femto-cells, 100% of the macro-cell's traffic to ten femto-cells, and to compare it with the case in-which traffic offloading is not applied. The QoS performance evaluation is based on the system's average throughput, Packet Loss Rate(PLR, average packet delay, and fairness among users. The LTE-Sim-5 with modifications is used in the simulation process. Simulation results show that offloading 100% of the Macro-cell's traffic to five femtocells had the highest maximum throughput, and the best PLR values especially when using the Log-Rule, in-which using it maintained the PLR values around 0.15 despite increasing the number of users. The least average packet delay was

  8. Study and Simulation of Traffic Behavior in Cellular Network

    Science.gov (United States)

    Madhup, D. K.; Shrestha, C. L.; Sharma, R. K.

    2007-07-01

    Cellular radio systems accommodate a large number of users with a limited radio spectrum. The concept of trunking allows a large number of users to share the relatively small number of channels in a cell by providing access to each user, on demand, from a pool of available channels. Traffic engineering deals with provisioning of communication circuits in a given area for a number of subscribers with a required grade of service. Traffic in any cell depends upon the number of users, the average request rate and average call duration. Certain number of channels is required for the required GOS. To design an optimum capacity cellular system, traffic behavior on that system is important. The number of channel required can be estimated by using Erlang formula and Erlang table. Erlang table is not always useful to calculate the probability of blocking in various complex scenarios such as channel borrowing strategies. When the total number of channel available in a given cell are divided to serve partly for newly generated calls and partly for handover calls, and if they use dynamic channel assignment strategies like channel borrowing, then the probability of blocking can't be calculated from Erlang table. Simulation model of the behavior help us to determine the blocking and the channel utilization while using various channel assignment strategies. The title "Study and Simulation of Traffic Behavior in Cellular Network" entail the study of the blocking probability of traffic in cellular network for static channel assignment strategies and dynamic channel borrowing strategies through MATLAB programming language and graphic user interface (GUI). The result shows that the dynamic scheme can perform better than static maximizing the overall utilization of the circuits and minimizing the overall blocking.

  9. Traffic Engineering of Cellular Wireless Communication Systems

    DEFF Research Database (Denmark)

    Iversen, Villy Bæk

    2002-01-01

    In mobile communications an efficient utilisation of the channels is of great importance. In this paper we describe the basic principles for obtaining the maximum utilisation and study strategies for obtaining these limits. In general a high degree of sharing is efficient, but requires service pr...... arrival processes, and multi-rate (multi-media) traffic for third generation systems....

  10. Residential Noise Control Requirements for Powerline Communications Channel

    OpenAIRE

    Guillen, Edward; Lopez, Julian; Padilla, Daniel

    2010-01-01

    Noises on powerline communication channels such as coloured noise, narrow band noise, periodic impulsive noise and asynchronous impulsive noise affect PLC network throughput. However, these noises can be successfully controlled by band-pass and bandstop filters installed on strategic PLC network connection points. It's necessary to establish a model to probe if the noise measurements on this work can be applied on industrial environments and if the noise can affect PLC networks installed on n...

  11. The requirements and challenges in preventing of road traffic injury in Iran. A qualitative study

    Directory of Open Access Journals (Sweden)

    Laflamme Lucie

    2009-12-01

    Full Text Available Abstract Background Road traffic injuries (RTIs are a major public health problem, especially in low- and middle-income countries. Among middle-income countries, Iran has one of the highest mortality rates from RTIs. Action is critical to combat this major public health problem. Stakeholders involved in RTI control are of key importance and their perceptions of barriers and facilitators are a vital source of knowledge. The aim of this study was to explore barriers to the prevention of RTIs and provide appropriate suggestions for prevention, based on the perceptions of stakeholders, victims and road-users as regards RTIs. Methods Thirty-eight semi-structured interviews were conducted with informants in the field of RTI prevention including: police officers; public health professionals; experts from the road administrators; representatives from the General Governor, the car industry, firefighters; experts from Emergency Medical Service and the Red Crescent; and some motorcyclists and car drivers as well as victims of RTIs. A qualitative approach using grounded theory method was employed to analyze the material gathered. Results The core variable was identified as "The lack of a system approach to road-user safety". The following barriers in relation to RTI prevention were identified as: human factors; transportation system; and organizational coordination. Suggestions for improvement included education (for the general public and targeted group training, more effective legislation, more rigorous law enforcement, improved engineering in road infrastructure, and an integrated organization to supervise and coordinate preventive activities. Conclusion The major barriers identified in this study were human factors and efforts to change human behaviour were suggested by means of public education campaigns and stricter law enforcement. However, the lack of a system approach to RTI prevention was also an important concern. There is an urgent need for both

  12. IDENTIFYING NETWORK LOAD BALANCING REQUIREMENTS ON HISTORICAL TRAFFIC FLOW USING MACHINE LEARNING APPROACH FOR FLEXIBLE MULTIPATH NETWORKS

    Directory of Open Access Journals (Sweden)

    K BALAMURUGAN

    2010-08-01

    Full Text Available Multipath routing uses several paths to distribute traffic from a source to destination. This not only improves network performance but also achieves load balancing and fault tolerance. Though multipath routing is not deployed widely in the internet, current systems chooses the paths with the same lowest cost to the destination and the same administrative distance.In this paper we propose a flexible multipath network wherein multipath routing algorithm is invoked when the quality of service is affected. Our proposal provides a method to gradually shift from a single path existing network to a reliable multipath network in the future.We have used machine learning approach to identify the instance when network load balancing is required with good results.

  13. Traffic Accident Prediction Model Implementation in Traffic Safety Management

    OpenAIRE

    Wen, Keyao

    2009-01-01

    As one of the highest fatalities causes, traffic accidents and collisions always requires a large amounteffort to be reduced or prevented from occur. Traffic safety management routines therefore always needefficient and effective implementation due to the variations of traffic, especially from trafficengineering point of view apart from driver education.Traffic Accident Prediction Model, considered as one of the handy tool of traffic safety management,has become of well followed with interest...

  14. Commercial Space Transportation and Air Traffic Insertion - SESAR Requirements and the European Perspective

    OpenAIRE

    Drescher, Jürgen; Morlang, Frank; Hampe, Jens; Kaltenhäuser, Sven; Jakobi, Jörn; Schmitt, Dirk-Roger

    2016-01-01

    Commercial Space Transportation becomes an international business and requires landing opportunities all over the world. Hence the integration of space vehicles in other airspace than the US NAS is an important topic to be considered. The Single European Sky ATM Research Programme (SESAR) is preparing the implementation of a new ATM system in Europe. The requirements are defined by the concept of the shared Business Trajectory and System Wide Information Management (SWIM).This paper describes...

  15. Reducing prospective memory error and costs in simulated air traffic control: External aids, extending practice, and removing perceived memory requirements.

    Science.gov (United States)

    Loft, Shayne; Chapman, Melissa; Smith, Rebekah E

    2016-09-01

    In air traffic control (ATC), forgetting to perform deferred actions-prospective memory (PM) errors-can have severe consequences. PM demands can also interfere with ongoing tasks (costs). We examined the extent to which PM errors and costs were reduced in simulated ATC by providing extended practice, or by providing external aids combined with extended practice, or by providing external aids combined with instructions that removed perceived memory requirements. Participants accepted/handed-off aircraft and detected conflicts. For the PM task, participants were required to substitute alternative actions for routine actions when accepting aircraft. In Experiment 1, when no aids were provided, PM errors and costs were not reduced by practice. When aids were provided, costs observed early in practice were eliminated with practice, but residual PM errors remained. Experiment 2 provided more limited practice with aids, but instructions that did not frame the PM task as a "memory" task led to high PM accuracy without costs. Attention-allocation policies that participants set based on expected PM demands were modified as individuals were increasingly exposed to reliable aids, or were given instructions that removed perceived memory requirements. These findings have implications for the design of aids for individuals who monitor multi-item dynamic displays. (PsycINFO Database Record PMID:27608067

  16. Fuel channel life limiting factors that dictate fuel channel maintenance requirements

    International Nuclear Information System (INIS)

    CANDU reactors have been operating for 33 years. The Nuclear Power Demonstration (NPD) Unit started up in 1962 and the prototype of CANDU, Douglas Point, started in 1967. The first commercial reactors, Pickering Units 1 and 2 both went into service in 1971 closely followed by Units 3 and 4 in 1972 and 1973 respectively. Operating commercial reactor experience represents over 10,000 pressure tubes, not including the replaced channels in all the Pickering A Units, and nearly 130,000 pressure tube operating years. No pressure tube has yet operated for its 30 year design lifetime of 210 KEFPH at 80% capacity factor. The longest operating time for pressure tubes to-date is about 120 KEFPH in Pickering Unit 4. Many lessons have been learned regarding pressure tube life limiting factors from the early CANDU units and these, together with the information obtained from an extensive pressure tube R and D program, have resulted in many design changes and improvements in material properties, mainly from manufacturing route changes. Reactors built recently are expected to achieve their 30 year design life. The development of Periodic and In-service Inspection programs and equipment, assessment methodologies and acceptance criteria, and the development of maintenance tooling and procedures are enabling the life limiting factors to be addressed in the currently operating units. The life limiting factors in currently operating Units are reviewed in relation to the experience gained from the early units, the R and D programs and the inspection and maintenance performed to date. (author)

  17. 33 CFR 149.565 - What are the required characteristics and intensity of lights on buoys used to define traffic lanes?

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false What are the required characteristics and intensity of lights on buoys used to define traffic lanes? 149.565 Section 149.565 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) DEEPWATER PORTS DEEPWATER PORTS: DESIGN, CONSTRUCTION, AND...

  18. Traffic Light Options

    OpenAIRE

    Løchte, Peter

    2006-01-01

    This paper introduces, prices, and analyzes traffic light options. The traffic light option is an innovative structured OTC derivative developed independently by several London-based investment banks to suit the needs of Danish life and pension (L&P) companies, which must comply with the traffic light solvency stress test system introduced by the Danish Financial Supervisory Authority (DFSA) in June 2001. This monitoring system requires L&P companies to submit regular reports documenting the ...

  19. Feeders-TDMA: a distributed-control algorithm for satellite channel capacity assignment in a mixed traffic and faded environment

    OpenAIRE

    Celandroni, Nedo; Ferro, Erina; Potort?, Francesco

    1997-01-01

    This paper presents Faded Environments Effective Distributed Engineering Redundant Signalling (FEEDERS), an access scheme for sharing, in time division multiple access (TDMA) mode, the capacity of a satellite channel among a number of stations, on the basis of user demand, This scheme and its companion Distributed Allocation with Request In Fixed Slots (DRIFS), result from a study carried out by the authors on distributed-control protocols for geostationary satellite access. Both protocols de...

  20. How Much Feedback Is Required for TDD Multi-Antenna Broadcast Channels with User Selection?

    Directory of Open Access Journals (Sweden)

    Salim Umer

    2010-01-01

    Full Text Available The enormous gains in a multi-antenna transmitter broadcast channel require the Channel State Information at the Transmitter (CSIT. Although the fundamental question "How much feedback is required for a broadcast channel?" has been treated in the literature to some extent, a more comprehensive treatment is certainly desirable. We study the time-division duplex broadcast channel with initial assumption of channel state information (CSI neither at the base station (BS nor at the users' side. We provide two transmission strategies through which the BS and the users get necessary CSI. We derive novel lower and upper bounds for the sum rate reflecting the rate loss compared to a perfect CSIT system. Corresponding approximate sum rate expressions are also developed for both schemes. These expressions fully capture the benefits of the CSIT feedback, allowing multi-user diversity gain and better inter-user interference cancellation, and the cost of exchange of information required. These expressions can be optimized for any set of system parameters to unveil the trade-off between the cost and the gains associated to feedback. Thus they allow to characterize the optimal amount of feedback which maximizes the sum rate of the broadcast channel, a well-accepted metric of system performance at the physical layer.

  1. 32 CFR 634.24 - Traffic planning and codes.

    Science.gov (United States)

    2010-07-01

    ... and minor routes, location of traffic control devices, and conditions requiring engineering or... Engineering Agency (SDDCTEA) will help installation commanders solve complex highway traffic engineering problems. SDDCTEA traffic engineering services include— (1) Traffic studies of limited areas and...

  2. Oligosaccharide composition of the neurotoxin responsive Na+ channel and the requirement of sialic acid for activity

    International Nuclear Information System (INIS)

    The neurotoxin responsive Na+ channel was purified to homogeneity in an 18% yield from a clonal cell line of mouse neuroblastoma, N-18, metabolically labeled with L-[3H]fucose. The Na+ channel, a glycoprotein, M/sub r/=200,000 (gradient 7-14% PAGE) was digested with Pronase and the glycopeptides were characterized by serial lectin affinity chromatography. greater than 90% of the oligosaccharides contained sialic acid and 18% were biantennary, 39% were triantennary and 30% tetraantennary. The glycoprotein was reconstituted into artificial phospholipid vesicles and 86Rb flux was stimulated (65%) by 200 μM veratridine and 1.2 μg of scorpion venom and was inhibited (95%) by 5 μM tetrodotoxin. The requirement of sialic acid for Na+ channel activity was demonstrated since neuraminidase (0.01 U) treatment of the reconstituted glycoprotein eliminated the response of 86Rb flux to the stimulating neurotoxins. In other experiments, treatment of N-18 cells with 10 μM swainsonine, an inhibitor of glycoprotein processing, altered the oligosaccharide composition of the Na+ channel. When the abnormally glycosylated Na+ channel was reconstituted into artificial phospholipid vesicles, 86Rb flux in response to neurotoxins was impaired. Thus, glycosylation of the polypeptide with oligosaccharides of specific composition and structure is essential for expression of the biological activity of the neurotoxin responsive Na+ channel

  3. Traffic Light Options

    DEFF Research Database (Denmark)

    Jørgensen, Peter Løchte

    This paper introduces, prices, and analyzes traffic light options. The traffic light option is an innovative structured OTC derivative developed independently by several London-based investment banks to suit the needs of Danish life and pension (L&P) companies, which must comply with the traffic...... light solvency stress test system introduced by the Danish Financial Supervisory Authority (DFSA) in June 2001. This monitoring system requires L&P companies to submit regular reports documenting the sensitivity of the companies' base capital to certain pre-defined market shocks - the red and yellow...... light scenarios. These stress scenarios entail drops in interest rates as well as in stock prices, and traffic light options are thus designed to pay off and preserve sufficient capital when interest rates and stock prices fall simultaneously. Sweden's FSA implemented a traffic light system in January...

  4. Traffic Light Options

    DEFF Research Database (Denmark)

    Jørgensen, Peter Løchte

    2007-01-01

    This paper introduces, prices, and analyzes traffic light options. The traffic light option is an innovative structured OTC derivative developed independently by several London-based investment banks to suit the needs of Danish life and pension (L&P) companies, which must comply with the traffic...... light solvency stress test system introduced by the Danish Financial Supervisory Authority (DFSA) in June 2001. This monitoring system requires L&P companies to submit regular reports documenting the sensitivity of the companies' base capital to certain pre-defined market shocks - the red and yellow...... light scenarios. These stress scenarios entail drops in interest rates as well as in stock prices, and traffic light options are thus designed to pay off and preserve sufficient capital when interest rates and stock prices fall simultaneously. Sweden's FSA implemented a traffic light system in January...

  5. HCN channels are not required for mechanotransduction in sensory hair cells of the mouse inner ear.

    Directory of Open Access Journals (Sweden)

    Geoffrey C Horwitz

    Full Text Available The molecular composition of the hair cell transduction channel has not been identified. Here we explore the novel hypothesis that hair cell transduction channels include HCN subunits. The HCN family of ion channels includes four members, HCN1-4. They were originally identified as the molecular correlates of the hyperpolarization-activated, cyclic nucleotide gated ion channels that carry currents known as If, IQ or Ih. However, based on recent evidence it has been suggested that HCN subunits may also be components of the elusive hair cell transduction channel. To investigate this hypothesis we examined expression of mRNA that encodes HCN1-4 in sensory epithelia of the mouse inner ear, immunolocalization of HCN subunits 1, 2 and 4, uptake of the transduction channel permeable dye, FM1-43 and electrophysiological measurement of mechanotransduction current. Dye uptake and transduction current were assayed in cochlear and vestibular hair cells of wildtype mice exposed to HCN channel blockers or a dominant-negative form of HCN2 that contained a pore mutation and in mutant mice that lacked HCN1, HCN2 or both. We found robust expression of HCNs 1, 2 and 4 but little evidence that localized HCN subunits in hair bundles, the site of mechanotransduction. Although high concentrations of the HCN antagonist, ZD7288, blocked 50-70% of the transduction current, we found no reduction of transduction current in either cochlear or vestibular hair cells of HCN1- or HCN2- deficient mice relative to wild-type mice. Furthermore, mice that lacked both HCN1 and HCN2 also had normal transduction currents. Lastly, we found that mice exposed to the dominant-negative mutant form of HCN2 had normal transduction currents as well. Taken together, the evidence suggests that HCN subunits are not required for mechanotransduction in hair cells of the mouse inner ear.

  6. Traffic Light Detection

    DEFF Research Database (Denmark)

    Philipsen, Mark Philip; Jensen, Morten Bornø; Møgelmose, Andreas;

    2015-01-01

    Traffic light recognition (TLR) is an integral part of any intelligent vehicle, which must function in the existing infrastructure. Pedestrian and sign detection have recently seen great improvements due to the introduction of learning based detectors using integral channel features. A similar push...... database is collected based on footage from US roads. The database consists of both test and training data, totaling 46,418 frames and 112,971 annotated traffic lights, captured in continuous sequences under a varying light and weather conditions. The learning based detector achieves an AUC of 0.4 and 0...

  7. Export of RNA silencing from C. elegans tissues does not require the RNA channel SID-1

    OpenAIRE

    Jose, Antony M.; Smith, Jessica J.; Hunter, Craig P.

    2009-01-01

    Double-stranded RNA (dsRNA) triggers RNA interference (RNAi) to silence genes of matching sequence. In some animals this experimentally induced silencing is transported between cells, and studies in the nematode Caenorhabditis elegans have shown that the dsRNA channel SID-1 is required for the import of such transported silencing signals. Gene silencing can also be triggered by endogenously expressed RNAi triggers, but it is unknown whether such silencing is transported between cells. Here, w...

  8. EFFICIENT UTILIZATION OF CHANNELS USING DYNAMIC GUARD CHANNEL ALLOCATION WITH CHANNEL BORROWING STRATEGY IN HANDOFFS

    Directory of Open Access Journals (Sweden)

    Alagu S

    2012-05-01

    Full Text Available User mobility in wireless data networks is increasing because of technological advances and the desire for voice and multimedia applications. These applications, however, require fast handoffs between base stations to maintain the quality of the connections. In this paper, the authors describe the use of novel and efficient data structure which dynamically allocates guard channel for handoffs and introduces the concept of channel borrowing strategy. The proposed scheme allocates the guard channels for handoff requests dynamically, based on the traffic load for certain time period. A new originating call in the cell coverage area also uses these guard channels if they are unused. Our basic idea is to allow Guard channels to be shared between new calls and handoff calls. This approach maximizes the channel utilization. The simulation results prove that the channel borrowing scheme improves the overall throughput.

  9. Mixing stream and datagram traffic on satellite: A FIFO Order-based Demand Assignment (FODA) Time Division Multiple Access (TDMA) scheme

    Science.gov (United States)

    Beltrame, R.; Bonito, A. B.; Celandroni, N.; Ferro, E.

    1985-11-01

    A FIFO Order based Demand Assignment (FODA) access scheme was designed to handle packetized data and voice traffic in a multiple access satellite broadcast channel of Mbits band. The channel is shared by as many as 64 simultaneously active stations in a range of 255 addressable stations. A sophisticated traffic environment is assumed, including different types of service requirements and an arbitrary load distribution among the stations. The results of 2Mbit/sec simulation tests for an existing hardware environment are presented.

  10. Models for Predictive Railway Traffic Management

    OpenAIRE

    Kecman, P.

    2014-01-01

    The potential growth in transport demand in the next decade and beyond requires a change from reactive to proactive traffic control to maintain and improve the reliability of railway traffic. In order to enable an anticipative approach to traffic management, it is necessary to develop the tools for monitoring, prediction and optimisation of the traffic operations. This thesis presents the models that can be used as components for a decision support system for predictive traffic management.

  11. Side channel analysis of some hash based MACs: A response to SHA-3 requirements

    DEFF Research Database (Denmark)

    Gauravaram, Praveen; Okeya, Katsuyuki

    The forthcoming NIST's Advanced Hash Standard (AHS) competition to select SHA-3 hash function requires that each candidate hash function submission must have at least one construction to support FIPS 198 HMAC application. As part of its evaluation, NIST is aiming to select either a candidate hash...... function which is more resistant to known side channel attacks (SCA) when plugged into HMAC, or that has an alternative MAC mode which is more resistant to known SCA than the other submitted alternatives. In response to this, we perform differential power analysis (DPA) on the possible smart card...

  12. MPLS & Internet Traffic Engineering%MPLS和Internet流量工程

    Institute of Scientific and Technical Information of China (English)

    孟魁; 张根度

    2001-01-01

    Rapid growth of Internet traffic and increasing requirement for service quality have made traffic engineering an essential consideration in the operation of large Internet backbone networks. Historically,traffic engineering in the Internet has been hampered by the conventional IP technologies. This article discusses the challenge of Internet Traffic Engineering and the applications of MPLS to traffic engineering in IP networks.

  13. Analysis of the use of DVB-RCS Resource Assignment Mechanisms for Internet Traffic

    Directory of Open Access Journals (Sweden)

    Gustavo Xavier Chafla

    2012-05-01

    Full Text Available This paper presents the simulation results of a satellite network based in the Digital Video Broadcast Standard for the outbound channel DVB-S and the return channel DVB-RCS for interactive satellite terminals called RCST. The network model was built under the Network Simulator NS and the main objective was to study the return channel DVB-RCS resource request mechanism and adaptation layer for carrying BE Internet traffic and real time flows. An approach that use rate based (RBDC requests for traffic with quality of service requirements, and volume based (VBDC requests for best effort traffic is proposed and evaluated for a corporate scenario that offers services such as voice over ip VoIP, videoconferencing and web surfing.

  14. Complexity in Air Traffic Management

    OpenAIRE

    Delahaye, Daniel; Puechmorel, Stéphane; Dougui, Nour Elhouda

    2009-01-01

    Air traffic Management Requirements : -Insure separation between aircraft. -Avoid costly manoeuvres and optionally optimize trajectories. -Insure trafic organization. Trends : -Separation delegated to aircraft. -Trajectory based air traffic management. -Introduction of decision support tools / automated conflict solvers. Workload : -Related to cognitive processes of human controllers. -Easy/Hard forecasting of conflict occurrence. -Monitoring is a non negligible part of the workload. -Relevan...

  15. Unbounded number of channel uses may be required to detect quantum capacity

    OpenAIRE

    Cubitt, Toby S.; Elkouss Coronas, David; Matthews, William; Ozols, M.; Pérez García, David; Strelchuk, S.

    2015-01-01

    Transmitting data reliably over noisy communication channels is one of the most important applications of information theory, and well understood when the channel is accurately modelled by classical physics. However, when quantum effects are involved, we do not know how to compute channel capacities. The capacity to transmit quantum information is essential to quantum cryptography and computing, but the formula involves maximising the coherent information over arbitrarily many channel uses. T...

  16. The Sodium-Activated Potassium Channel Slack Is Required for Optimal Cognitive Flexibility in Mice

    Science.gov (United States)

    Bausch, Anne E.; Dieter, Rebekka; Nann, Yvette; Hausmann, Mario; Meyerdierks, Nora; Kaczmarek, Leonard K.; Ruth, Peter; Lukowski, Robert

    2015-01-01

    "Kcnt1" encoded sodium-activated potassium channels (Slack channels) are highly expressed throughout the brain where they modulate the firing patterns and general excitability of many types of neurons. Increasing evidence suggests that Slack channels may be important for higher brain functions such as cognition and normal intellectual…

  17. Traffic Light Detection

    DEFF Research Database (Denmark)

    Philipsen, Mark Philip; Jensen, Morten Bornø; Møgelmose, Andreas; Moeslund, Thomas B.; Trivedi, Mohan M.

    Traffic light recognition (TLR) is an integral part of any intelligent vehicle, which must function in the existing infrastructure. Pedestrian and sign detection have recently seen great improvements due to the introduction of learning based detectors using integral channel features. A similar push...... database is collected based on footage from US roads. The database consists of both test and training data, totaling 46,418 frames and 112,971 annotated traffic lights, captured in continuous sequences under a varying light and weather conditions. The learning based detector achieves an AUC of 0.4 and 0...... have not yet been seen for the detection sub-problem of TLR, where detection is dominated by methods based on heuristic models. Evaluation of existing systems is currently limited primarily to small local datasets. In order to provide a common basis for comparing future TLR research an extensive public...

  18. Do Voltage-Dependent K^+ Channels Require Ca2+? A Critical Test Employing a Heterologous Expression System

    Science.gov (United States)

    Armstrong, Clay M.; Miller, Christopher

    1990-10-01

    Removal of Ca2+ from the solution bathing neurons is known in many cases to alter the gating properties of voltage-dependent K^+ channels and to induce a large, nonselective "leak" conductance. We used a heterologous expression system to test whether the leak conductance observed in neurons is mediated by voltage-dependent K^+ channels in an altered, debased conformation. Voltage-dependent K^+ channels were expressed in an insect cell line infected with a recombinant baculovirus carrying the cDNA for Drosophila Shaker "A-type" K^+ channels. These expressed channels respond to low Ca2+ identically to voltage-dependent K^+ channels in native neuronal membranes; upon removal of external Ca2+, Shaker K^+ currents disappear and are replaced by a steady, nonselective leak conductance. However, control cells devoid of Shaker channels were free of any voltage-dependent conductances and did not generate a leak when external Ca2+ was removed. These results show that Ca2+ is essential for proper function of voltage-dependent K^+ channels and is required to stabilize the native conformations of these membrane proteins.

  19. An application of queueing theory to the design of channel requirements for special purpose communications satellites. Ph.D. Thesis

    Science.gov (United States)

    Hein, G. F.

    1974-01-01

    Special purpose satellites are very cost sensitive to the number of broadcast channels, usually will have Poisson arrivals, fairly low utilization (less than 35%), and a very high availability requirement. To solve the problem of determining the effects of limiting C the number of channels, the Poisson arrival, infinite server queueing model will be modified to describe the many server case. The model is predicated on the reproductive property of the Poisson distribution.

  20. Light signals for road traffic control.

    OpenAIRE

    Schreuder, D.A.

    1981-01-01

    Signals for road traffic control are a major constituent of the modern traffic scene, particularly in built-up areas. A vast amount of research has been executed in the last two decennia, resulting in a fairly generally accepted view on what the requirements for effective traffic lights are. For the French translation see B 19780

  1. Dynamic traffic grooming in survivable WDM networks

    Science.gov (United States)

    Zhu, Yonghua; Lin, Rujian

    2005-11-01

    This paper investigates the survivable traffic grooming problem for optical mesh networks employing wavelength-division multiplexing (WDM). While the transmission rate of a wavelength channel is high, the bandwidth requirement of a typical connection request can vary from the full wavelength capacity down to subwavelength. To efficiently utilize network resources, subwavelength-granularity connections can be groomed onto direct optical transmission channels, or lightpaths. Meanwhile, the failure of a network element can cause the failure of several lightpaths, thereby leading to large data and revenue loss. Fault-management schemes such as protection are essential to survive such failures. Different low-speed connections may request different bandwidth granularities as well as different protection schemes. How to efficiently groom such low-speed connections while satisfying their protection requirements is the main focus of our investigation. The paper tackles the dynamic survivable traffic grooming problems in multifiber wavelength-routed optical networks by representing the network as a layered graph model. This graph multi layers, where each layer represents a specific wavelength. Each link in the layered graph has more than one fibers and an associated cost. We use a modified Dijkstra algorithm that has a reduced complexity due to the structure of the layered graph. Heuristic algorithms for fiber selection based on a well-designed link-cost metrics are proposed. The performance of various routing algorithms is evaluated through simulation studies.

  2. A Traffic Advisory System for Islamabad

    OpenAIRE

    Irfan Younas; Muhammad Ilyas; Riaz Ali

    2008-01-01

    Traffic congestion is an increasing problem in urban environments. As cities develop, more traffic is featuring on the roads. However, adequate and timely measures are required in terms of infrastructure development to facilitate smooth flow of traffic. In this research we have designed and implemented a traffic advisory system for Islamabad, Pakistan. This system advises the commuter of the shortest route to destination, alternative route in case of congestion or when an incident has occur...

  3. Traffic Light Controller Using Fpga

    Directory of Open Access Journals (Sweden)

    D.Bhavana

    2015-04-01

    Full Text Available The traffic light sequence works on the specific switching of Red, Green and Yellow lights in a particular way with stipulated time form. The normal function of traffic lights requires sophisticated control and coordination to ensure that traffic moves as smoothly and safely as possible and that pedestrians are protected when they cross the roads [1] .This Traffic Light sequence is generated using a specific switching mechanism which will help to control a traffic light system on a road in a specified sequence. This paper focuses on the fact that the traffic lights can be varied in the day and night mode depending on the intensity of the traffic. It plays a vital role in supervising and running the metropolitan traffic and evade the possibilities of any unfortunate mishaps happening in and around the cities. It is a sequential machine to be scrutinized as per the requirements and programmed through a multistep development process. The methods that are used in this project are proposing the circuit, write a code, simulate, synthesis and implement on the hardware [8] . In this project, XILINX Software was chosen to devise a schematic using schematic edit, write a code using Verilog HDL (Hardware Description Language text editor and implements the circuit on Programmable Logic Device [PLD].The system has been successfully tested and implemented in hardware using Nexys 2 Digilent FPGA.

  4. Mechanotransduction in mouse inner ear hair cells requires transmembrane channel-like genes

    NARCIS (Netherlands)

    Kawashima, Yoshiyuki; Geleoc, Gwenaelle S. G.; Kurima, Kiyoto; Labay, Valentina; Lelli, Andrea; Asai, Yukako; Makishima, Tomoko; Wu, Doris K.; Della Santina, Charles C.; Holt, Jeffrey R.; Griffith, Andrew J.

    2011-01-01

    Inner ear hair cells convert the mechanical stimuli of sound, gravity, and head movement into electrical signals. This mechanotransduction process is initiated by opening of cation channels near the tips of hair cell stereocilia. Since the identity of these ion channels is unknown, and mutations in

  5. REQUIREMENTS OF MODERNIZATION ASSESSMENT AND MAINTENANCE OF THE NORTH CHANNEL OF OBRA

    Directory of Open Access Journals (Sweden)

    Paweł Kozaczyk

    2015-07-01

    Full Text Available In an attempt to assess the needs of the modernization of the North Channel of Obra, the construction began in 1852. The condition of drainage occurring on this course coming generally from the early 20th century and is unsatisfactory. This is the result of longstanding neglect and lack of maintenance. The first modernization works started in 1986. Undergoing on the North Channel of Obra are primarily made in the framework of four tasks, which was the regulation of the water course on a length of approximately 35 km 8 dams were built and 9 dams were demolished. The cost of upgrading the North Channel of The Obra was significantly different, what is the result of the works. They include the cost of reconstruction of the drainage channels, and the reconstruction of hydraulic structures. At this work, in addition to the needs assessment of the North Channel of Obra, further modernization needs were indicated.

  6. Statistical Multiplexing of Video Traffic and Data Traffic

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    This paper studies statistical multiplexing performance byinput of video traffic and data traffic. The inputs have different Qos requirements such as loss and delay jitter. By applying a modified FBM model, we present methods to estimate effective bandwidth of the aggregated traffic. Simulationswere paformed to evaluate effective bandwidth. The comparison between the estimation and the simulation shows that the estimations can give correct data for the effective bandwidths in terms of our interests. The analysis of gain by using priority multiplexing also addresses proper Qos configuration for the inputs in order to achieve positive gains.

  7. The β1-subunit of Na(v1.5 cardiac sodium channel is required for a dominant negative effect through α-α interaction.

    Directory of Open Access Journals (Sweden)

    Aurélie Mercier

    Full Text Available Brugada syndrome (BrS is an inherited autosomal dominant cardiac channelopathy. Several mutations on the cardiac sodium channel Na(v1.5 which are responsible for BrS lead to misfolded proteins that do not traffic properly to the plasma membrane. In order to mimic patient heterozygosity, a trafficking defective mutant, R1432G was co-expressed with Wild Type (WT Na(v1.5 channels in HEK293T cells. This mutant significantly decreased the membrane Na current density when it was co-transfected with the WT channel. This dominant negative effect did not result in altered biophysical properties of Na(v1.5 channels. Luminometric experiments revealed that the expression of mutant proteins induced a significant reduction in membrane expression of WT channels. Interestingly, we have found that the auxiliary Na channel β(1-subunit was essential for this dominant negative effect. Indeed, the absence of the β(1-subunit prevented the decrease in WT sodium current density and surface proteins associated with the dominant negative effect. Co-immunoprecipitation experiments demonstrated a physical interaction between Na channel α-subunits. This interaction occurred only when the β(1-subunit was present. Our findings reveal a new role for β(1-subunits in cardiac voltage-gated sodium channels by promoting α-α subunit interaction which can lead to a dominant negative effect when one of the α-subunits shows a trafficking defective mutation.

  8. Effect of Ad-Hoc Vehicular Network on Traffic Flow: Simulations in the Context of Three-Phase Traffic Theory

    OpenAIRE

    Kerner, B. S.; Klenov, S. L.; Brakemeier, A.

    2009-01-01

    Effects of vehicle-to-vehicle (or/and vehicle-to-infrastructure communication, called also V2X communication)on traffic flow, which are relevant for ITS, are numerically studied. To make the study adequate with real measured traffic data, a testbed for wireless vehicle communication based on a microscopic model in the framework of three-phase traffic theory is developed and discussed. In this testbed, vehicle motion in traffic flow and analyses of a vehicle communication channel access based ...

  9. BK channels in microglia are required for morphine-induced hyperalgesia.

    Science.gov (United States)

    Hayashi, Yoshinori; Morinaga, Saori; Zhang, Jing; Satoh, Yasushi; Meredith, Andrea L; Nakata, Takahiro; Wu, Zhou; Kohsaka, Shinichi; Inoue, Kazuhide; Nakanishi, Hiroshi

    2016-01-01

    Although morphine is a gold standard medication, long-term opioid use is associated with serious side effects, such as morphine-induced hyperalgesia (MIH) and anti-nociceptive tolerance. Microglia-to-neuron signalling is critically involved in pain hypersensitivity. However, molecules that control microglial cellular state under chronic morphine treatment remain unknown. Here we show that the microglia-specific subtype of Ca(2+)-activated K(+) (BK) channel is responsible for generation of MIH and anti-nociceptive tolerance. We find that, after chronic morphine administration, an increase in arachidonic acid levels through the μ-opioid receptors leads to the sole activation of microglial BK channels in the spinal cord. Silencing BK channel auxiliary β3 subunit significantly attenuates the generation of MIH and anti-nociceptive tolerance, and increases neurotransmission after chronic morphine administration. Therefore, microglia-specific BK channels contribute to the generation of MIH and anti-nociceptive tolerance. PMID:27241733

  10. Intelligent Ambulance Traffic Assistance System

    Directory of Open Access Journals (Sweden)

    RONOJOY GHOSH

    2013-09-01

    Full Text Available With the increase in traffic road density, several causalities occur due to delay in taking a patient to the hospital in an ambulance. In this paper, we have developed an algorithm to find the shortest path to reach the required destination. As required the software will identify the present location of the vehicle and ask the user for the destination. Then it will show all the available paths, highlighting the shortest one or in several cases the most optimum one. Further we made the traffic signals automated for special vehicles like an ambulance or a fire-engine such that the signals will go green for the ambulance as it comes in the vicinity of the traffic signal, thus providing them with a clear path to reach its destination. The original signal is restored as soon as the ambulance goes undetected by the Bluetooth scanner of the traffic signal.

  11. Packet Scheduling for Downlink OFDMA Wireless Systems with Heterogeneous Traffic

    Directory of Open Access Journals (Sweden)

    Cui-Qin Dai

    2012-06-01

    Full Text Available In this paper, we propose a packet scheduling algorithm for downlink OFDMA wireless systems in which users have heterogeneous traffic. The proposed scheduling algorithm not only focuses on channel state and fairness but also takes the users’ queue length into consideration. With the idea of beta deadline parameter, we convert the delay bound of real-time traffic to date rate domain QoS parameter, and extend the idea for non real-time traffic with the minimum average throughput requirement. According to the subscribers’ QoS parameter, we divide the whole band into chunks with different size flexibly. Chunks are allocated to users in accordance with the scheduling rule. Simulation results demonstrate that the proposed scheduling algorithm can acclimatize itself to active user number in the system and the users’ requirements for radio resource. Its performance in terms of spectral efficiency, packet loss ratio, and the real-time traffic packets’ delay, is better than algorithms with fixed chunk size dividing.

  12. Technical Documentation in Traffic Technology

    OpenAIRE

    Čurepić, Danko; Toš, Zdravko

    2009-01-01

    The requirements for the prompt usage of traffic infrastructure capacities define the technological frames which ensure updated maintenance and development of new traffic infrastructure capacities by implementing graphical and computer systems. Technical documentation (TD) based on the technology of geographic information systems (GIS) allows fast analysis of graphical and alphanumerical data with the aim of identifying spatial relations among various cartographic elements. The paper analyses...

  13. Lost in traffic? The K+ channel of lily pollen, LilKT1, is detected at the endomembranes inside yeast cells, tobacco leaves and lily pollen

    Directory of Open Access Journals (Sweden)

    Minou Jasmin Safiarian

    2015-02-01

    Full Text Available Fertilization in plants relies on fast growth of pollen tubes through the style tissue towards the ovules. This polarized growth depends on influx of ions and water to increase the tube’s volume. K+ inward rectifying channels were detected in many pollen species, with one identified in Arabidopsis. Here, an Arabidopsis AKT1-like channel (LilKT1 was identified from Lilium longiflorum pollen. Complementation of K+ uptake deficient yeast mutants was only successful when the entire LilKT1 C-terminus was replaced by the AKT1 C-terminus. No signals were observed in the plasma membrane (PM of pollen tubes after expression of fluorescence-tagged LilKT1 nor were any LilKT1-derived peptides detectable in the pollen PM by mass spectrometry analysis. In contrast, fluorescent LilKT1 partly co-localized with the lily PM H+ ATPase LilHA2 in the PM of tobacco leaf cells, but exhibited a punctual fluorescence pattern and also sub-plasma membrane localization. Thus, incorporation of LilKT1 into the pollen PM seems tighter controlled than in other cells with still unknown trafficking signals in LilKT1’s C-terminus, resulting in channel densities below detection limits. This highly controlled incorporation might have physiological reasons: an uncontrolled number of K+ inward channels in the pollen PM will give an increased water influx due to the raising cytosolic K+ concentration, and finally, causing the tube to burst.

  14. Research on green channel system of first aid to highway traffic accident injury in Kunming city%昆明市军警联动高速公路急救绿色通道体系研究

    Institute of Scientific and Technical Information of China (English)

    刘军; 郝江; 边革元; 江岩

    2012-01-01

    Objective To study the current situation in the first aid of highway traffic accident injury in Kunming city, and to discuss and improve the first aid pattern through highway green channel established by the joint military and police. Methods Through the establishment of joint military and police first aid system, the coordination in calling emergency, sending an ambulance, field first aid,conveying,and hospitalized emergency care were specified by regulations and strengthened. Results Joint military and police green channel of highway first aid was superior to the traditional first aid system in the aspects of reaction time, successful rescue rate. Conclusion It is worthwhile to further promote the joint military and police green channel of highway first aid.%目的 研究昆明市高速公路交通伤急救的现状,探讨完善军警联动高速公路绿色通道急救模式.方法 通过设立紧急军警联动急救体系,在呼救协调、出车、现场急救、转运、院内抢救等方面给予制度规范及加强.结果 军警联动急救高速公路绿色通道在反应时间、抢救成功率上,均明显优于传统急救体系.结论 军警联动急救高速公路绿色通道值得进一步推广.

  15. Cation Selectivity by the CorA Mg2+ Channel Requires a Fully Hydrated Cation†

    OpenAIRE

    Moomaw, Andrea S.; Maguire, Michael E.

    2010-01-01

    The CorA Mg2+ channel is the primary uptake system in about half of all bacteria and archaea. However, the basis for its Mg2+ selectivity is unknown. Previous data suggested that CorA binds a fully hydrated Mg2+ ion, unlike other ion channels. The crystal structure of Thermotoga maritima CorA shows a homopentamer with two transmembrane segments per monomer connected by a short periplasmic loop. This highly conserved loop, 281EFMPELKWS289 in Salmonella enterica serovar Typhimurium CorA, is the...

  16. Analysis of Dynamic Road Traffic Congestion Control (DRTCC) Techniques

    OpenAIRE

    Pardeep Mittal; Yashpal Singh,; Yogesh Sharma

    2015-01-01

    : Dynamic traffic light control at intersection has become one of the most active research areas to develop the Dynamic transportation systems (ITS). Due to the consistent growth in urbanization and traffic congestion, such a system was required which can control the timings of traffic lights dynamically with accurate measurement of traffic on the road. In this paper, analysis of all the techniques that has been developed to automate the traffic lights has been done.. The efficacy...

  17. Adaptive network traffic management for multi user virtual environments

    OpenAIRE

    Oliver, Iain Angus

    2011-01-01

    Multi User Virtual Environments (MUVE) are a new class of Internet application with a significant user base. This thesis adds to our understanding of how MUVE network traffic fits into the mix of Internet traffic, and how this relates to the application's needs. MUVEs differ from established Internet traffic types in their requirements from the network. They differ from traditional data traffic in that they have soft real-time constraints, from game traffic in that their bandwidth requi...

  18. Activation of L-type calcium channels is required for gap junction-mediated intercellular calcium signaling in osteoblastic cells

    DEFF Research Database (Denmark)

    Jørgensen, Niklas Rye; Teilmann, Stefan Cuoni; Henriksen, Zanne;

    2003-01-01

    The propagation of mechanically induced intercellular calcium waves (ICW) among osteoblastic cells occurs both by activation of P2Y (purinergic) receptors by extracellular nucleotides, resulting in "fast" ICW, and by gap junctional communication in cells that express connexin43 (Cx43), resulting in...... extracellular calcium, plasma membrane depolarization by high extracellular potassium, and the L-type voltage-operated calcium channel inhibitor, nifedipine. In contrast, all these treatments enhanced the spread of P2 receptor-mediated ICW in UMR rat osteoblastic cells. Using UMR cells transfected to express Cx......43 (UMR/Cx43) we confirmed that nifedipine sensitivity of ICW required Cx43 expression. In human osteoblastic cells, gap junction-dependent ICW also required activation of L-type calcium channels and influx of extracellular calcium....

  19. The TRPM2 ion channel is required for sensitivity to warmth.

    Science.gov (United States)

    Tan, Chun-Hsiang; McNaughton, Peter A

    2016-08-25

    Thermally activated ion channels are known to detect the entire thermal range from extreme heat (TRPV2), painful heat (TRPV1, TRPM3 and ANO1), non-painful warmth (TRPV3 and TRPV4) and non-painful coolness (TRPM8) through to painful cold (TRPA1). Genetic deletion of each of these ion channels, however, has only modest effects on thermal behaviour in mice, with the exception of TRPM8, the deletion of which has marked effects on the perception of moderate coolness in the range 10-25 °C. The molecular mechanism responsible for detecting non-painful warmth, in particular, is unresolved. Here we used calcium imaging to identify a population of thermally sensitive somatosensory neurons which do not express any of the known thermally activated TRP channels. We then used a combination of calcium imaging, electrophysiology and RNA sequencing to show that the ion channel generating heat sensitivity in these neurons is TRPM2. Autonomic neurons, usually thought of as exclusively motor, also express TRPM2 and respond directly to heat. Mice in which TRPM2 had been genetically deleted showed a striking deficit in their sensation of non-noxious warm temperatures, consistent with the idea that TRPM2 initiates a 'warm' signal which drives cool-seeking behaviour. PMID:27533035

  20. An organelle K+ channel is required for osmoregulation in Chlamydomonas reinhardtii.

    Science.gov (United States)

    Xu, Feifei; Wu, Xiaoan; Jiang, Lin-Hua; Zhao, Hucheng; Pan, Junmin

    2016-08-01

    Fresh water protozoa and algae face hypotonic challenges in their living environment. Many of them employ a contractile vacuole system to uptake excessive water from the cytoplasm and expel it to the environment to achieve cellular homeostasis. K(+), a major osmolyte in contractile vacuole, is predicted to create higher osmolarity for water influx. Molecular mechanisms for K(+) permeation through the plasma membrane have been well studied. However, how K(+) permeates organelles such as the contractile vacuole is not clear. Here, we show that the six-transmembrane K(+) channel KCN11 in Chlamydomonas is exclusively localized to contractile vacuole. Ectopic expression of KCN11 in HEK293T cells results in voltage-gated K(+) channel activity. Disruption of the gene or mutation of key residues for K(+) permeability of the channel leads to dysfunction of cell osmoregulation in very hypotonic conditions. The contractile cycle is inhibited in the mutant cells with a slower rate of contractile vacuole swelling, leading to cell death. These data demonstrate a new role for six-transmembrane K(+) channels in contractile vacuole functioning and provide further insights into osmoregulation mediated by the contractile vacuole. PMID:27311484

  1. Death of Neurons following Injury Requires Conductive Neuronal Gap Junction Channels but Not a Specific Connexin.

    Science.gov (United States)

    Fontes, Joseph D; Ramsey, Jon; Polk, Jeremy M; Koop, Andre; Denisova, Janna V; Belousov, Andrei B

    2015-01-01

    Pharmacological blockade or genetic knockout of neuronal connexin 36 (Cx36)-containing gap junctions reduces neuronal death caused by ischemia, traumatic brain injury and NMDA receptor (NMDAR)-mediated excitotoxicity. However, whether Cx36 gap junctions contribute to neuronal death via channel-dependent or channel-independent mechanism remains an open question. To address this, we manipulated connexin protein expression via lentiviral transduction of mouse neuronal cortical cultures and analyzed neuronal death twenty-four hours following administration of NMDA (a model of NMDAR excitotoxicity) or oxygen-glucose deprivation (a model of ischemic injury). In cultures prepared from wild-type mice, over-expression and knockdown of Cx36-containing gap junctions augmented and prevented, respectively, neuronal death from NMDAR-mediated excitotoxicity and ischemia. In cultures obtained form from Cx36 knockout mice, re-expression of functional gap junction channels, containing either neuronal Cx36 or non-neuronal Cx43 or Cx31, resulted in increased neuronal death following insult. In contrast, the expression of communication-deficient gap junctions (containing mutated connexins) did not have this effect. Finally, the absence of ethidium bromide uptake in non-transduced wild-type neurons two hours following NMDAR excitotoxicity or ischemia suggested the absence of active endogenous hemichannels in those neurons. Taken together, these results suggest a role for neuronal gap junctions in cell death via a connexin type-independent mechanism that likely relies on channel activities of gap junctional complexes among neurons. A possible contribution of gap junction channel-permeable death signals in neuronal death is discussed. PMID:26017008

  2. A Traffic Advisory System for Islamabad

    Directory of Open Access Journals (Sweden)

    Irfan Younas

    2008-09-01

    Full Text Available Traffic congestion is an increasing problem in urban environments. As cities develop, more traffic is featuring on the roads. However, adequate and timely measures are required in terms of infrastructure development to facilitate smooth flow of traffic. In this research we have designed and implemented a traffic advisory system for Islamabad, Pakistan. This system advises the commuter of the shortest route to destination, alternative route in case of congestion or when an incident has occurred. In addition it can provide information about major landmarks on the route, so that commuter can be advised of necessary information of the city if required. This system can also advise the civil authorities of particular traffic bottle necks in order for necessary road or traffic rectifications to be made.

  3. Synaptic Ribbons Require Ribeye for Electron Density, Proper Synaptic Localization, and Recruitment of Calcium Channels.

    Science.gov (United States)

    Lv, Caixia; Stewart, William J; Akanyeti, Otar; Frederick, Courtney; Zhu, Jie; Santos-Sacchi, Joseph; Sheets, Lavinia; Liao, James C; Zenisek, David

    2016-06-21

    Synaptic ribbons are structures made largely of the protein Ribeye that hold synaptic vesicles near release sites in non-spiking cells in some sensory systems. Here, we introduce frameshift mutations in the two zebrafish genes encoding for Ribeye and thus remove Ribeye protein from neuromast hair cells. Despite Ribeye depletion, vesicles collect around ribbon-like structures that lack electron density, which we term "ghost ribbons." Ghost ribbons are smaller in size but possess a similar number of smaller vesicles and are poorly localized to synapses and calcium channels. These hair cells exhibit enhanced exocytosis, as measured by capacitance, and recordings from afferent neurons post-synaptic to hair cells show no significant difference in spike rates. Our results suggest that Ribeye makes up most of the synaptic ribbon density in neuromast hair cells and is necessary for proper localization of calcium channels and synaptic ribbons. PMID:27292637

  4. Phosphorylation of rat aquaporin-4 at Ser(111) is not required for channel gating

    DEFF Research Database (Denmark)

    Assentoft, Mette; Kaptan, Shreyas; Fenton, Robert A;

    2013-01-01

    is therefore of therapeutic interest. Phosphorylation of some aquaporins has been proposed to regulate their water permeability via gating of the channel itself. Protein kinase (PK)-dependent phosphorylation of Ser(111) has been reported to increase the water permeability of AQP4 expressed in an astrocytic......Aquaporin 4 (AQP4) is the predominant water channel in the mammalian brain and is mainly expressed in the perivascular glial endfeet at the brain-blood interface. AQP4 has been described as an important entry and exit site for water during formation of brain edema and regulation of AQP4...... cell line. This possibility was, however, questioned based on the crystal structure of the human AQP4. Our study aimed to resolve if Ser(111) was indeed a site involved in phosphorylation-mediated gating of AQP4. The water permeability of AQP4-expressing Xenopus oocytes was not altered by a range...

  5. The Effect of Channel Fading on Providing Quality

    Directory of Open Access Journals (Sweden)

    Marzieh Varposhti

    2008-09-01

    Full Text Available Transferring real-time traffic such as voice and video over wireless LAN network (WLAN requires stringent delay and jitter requirements. One of the methods to provide QoS in this standard is Enhanced Distributed Channel Access (EDCA which benefits form the concept of traffic categories. However, EDCA is a contention based method; therefore it can not guarantee strict QoS required by real-time services without proper network control mechanisms. One of the challenging problems in wireless networks is the failure of transmitting media due to fading. Normally the node does not differentiate between the media access collision and the channel failure. The performance of this method in case of fading channel has not yet been evaluated. In this paper, we analyze the effect of loss and delay caused by fading channel on EDCA performance. Then, we propose a modification to the media access scheme to elevate the performance against channel failures. Moreover an adjustment for the maximum number of retransmissions is proposed to maintain the delay and jitter requirements of the real-time traffic. The performances of the proposed methods are evaluated by simulations.

  6. QoS Support Polling Scheme for Multimedia Traffic in Wireless LAN MAC Protocol

    Institute of Scientific and Technical Information of China (English)

    YANG Zhijun; ZHAO Dongfeng

    2008-01-01

    Quality of service (QoS) support is a key attribute for multimedia traffic including video, voice, and data in wireless local area networks (LANs) but is limited in 802.11-based wireless LANs. A polling-based scheme called the point coordination function (PCF) was developed for 802.11 LANs to support the trans-mission of multimedia traffic. However, the PCF is not able to meet the desired practical traffic differentiation requirements for real-time data. This paper describes a QoS support polling scheme based on the IEEE 802.11 medium access control (MAC) protocol. The scheme uses a two-level polling mechanism with the QoS classes differentiated by two different access policies. Stations with higher priority traffic such as key or real-time data form the first level and can access the common channel through an exhaustive access policy. Other stations with lower priority traffic form the second level and can access the channel through a gated access policy. A system model based on imbedded Markov chain theory and a generation function were setup to explicitly analyze the mean information packet waiting time of the two-level polling scheme. Theo-retical and simulation results show that the new scheme efficiently differentiates services to guarantee better QoS and system stability.

  7. Jamitons: Phantom Traffic Jams

    Science.gov (United States)

    Kowszun, Jorj

    2013-01-01

    Traffic on motorways can slow down for no apparent reason. Sudden changes in speed by one or two drivers can create a chain reaction that causes a traffic jam for the vehicles that are following. This kind of phantom traffic jam is called a "jamiton" and the article discusses some of the ways in which traffic engineers produce…

  8. A TRAFFIC OVERSTOCK RESLOVE SCHEME IN WLAN

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A new Multiple Access Control (MAC) protocol-User Adaptive Scheduling Multiple Access (UASMA) protocol is proposed in this paper. It can well schedule the packet transmission according to the exact number of active Mobile Terminals (MTs) determined by selforganizing algorithm and adjust the number of packets sent by one node in one frame properly.UASMA protocol employs a special frame structure, which makes it possible to allocate channel resource to uplink and downlink traffic according to their respective service requirements. The proposed concept of referenced-frame-length can ensure the frame length varies in a certain range,and consequently increase the utilization efficiency of the channel greatly. Meanwhile, UASMA protocol uses an efficient collision resolution algorithm to guarantee that active MTs can access the channel rapidly. Finally, the performance of UASMA protocol is evaluated by simulation and it is also compared with carrier sense multiple access, rounding-poll and UPMA protocols. The results show that the UASMA has better performance than others.

  9. Side channel analysis of some hash based MACs: A response to SHA-3 requirements

    DEFF Research Database (Denmark)

    Gauravaram, Praveen; Okeya, Katsuyuki

    2008-01-01

    function which is more resistant to known side channel attacks (SCA) when plugged into HMAC, or that has an alternative MAC mode which is more resistant to known SCA than the other submitted alternatives. In response to this, we perform differential power analysis (DPA) on the possible smart card....../HMAC against the DPA attacks, whereas multi-lane NMAC, EMD MAC and the keyed wide-pipe hash have similar security to NMAC against the DPA attacks. Our DPA attacks do not work on the NMAC setting of MDC-2, Grindahl and MAME compression functions....

  10. Side channel analysis of some hash based MACs:A response to SHA-3 requirements

    DEFF Research Database (Denmark)

    function which is more resistant to known side channel attacks (SCA) when plugged into HMAC, or that has an alternative MAC mode which is more resistant to known SCA than the other submitted alternatives. In response to this, we perform differential power analysis (DPA) on the possible smart card....../HMAC against the DPA attacks, whereas multi-lane NMAC, EMD MAC and the keyed wide-pipe hash have similar security to NMAC against the DPA attacks. Our DPA attacks do not work on the NMAC setting of MDC-2, Grindahl and MAME compression functions. This talk outlines our results....

  11. General requirement for harvesting antennae at Ca2+ and H+ channels and transporters

    Directory of Open Access Journals (Sweden)

    Cristián Martínez

    2010-09-01

    Full Text Available The production and dissipation of energy in cells is intimately linked to the movement of small molecules in and out of enzymes, channels and transporters. An analytical model of diffusion was described previously, which was used to estimate local effects of these proteins acting as molecular sources. The present article describes a simple but more general model, which can be used to estimate the local impact of proteins acting as molecular sinks. The results show that the enzymes, transporters and channels, whose substrates are present at relatively high concentrations like ATP, Na+, glucose, lactate and pyruvate, do not operate fast enough to deplete their vicinity to a meaningful extent, supporting the notion that for these molecules the cytosol is a well-mixed compartment. One specific consequence of this analysis is that the well-documented cross-talk existing between the Na+/K+ ATPase and the glycolytic machinery should not be explained by putative changes in local ATP concentration. In contrast, Ca2+ and H+ transporters like the Na+/Ca2+ exchanger NCX and the Na+/H+ exchanger NHE, show experimental rates of transport that are two to three orders of magnitude faster than the rates at which the aqueous phase may possibly feed their binding sites. This paradoxical result implies that Ca2+ and H+ transporters do not extract their substrates directly from the bulk cytosol, but from an intermediate “harvesting” compartment located between the aqueous phase and the transport site.

  12. HYBRID INTERNET TRAFFIC CLASSIFICATION TECHNIQUE1

    Institute of Scientific and Technical Information of China (English)

    Li Jun; Zhang Shunyi; Lu Yanqing; Yan Junrong

    2009-01-01

    Accurate and real-time classification of network traffic is significant to network operation and management such as QoS differentiation, traffic shaping and security surveillance. However, with many newly emerged P2P applications using dynamic port numbers, masquerading techniques, and payload encryption to avoid detection, traditional classification approaches turn to be ineffective. In this paper, we present a layered hybrid system to classify current Internet traffic, motivated by variety of network activities and their requirements of traffic classification. The proposed method could achieve fast and accurate traffic classification with low overheads and robustness to accommodate both known and unknown/encrypted applications. Furthermore, it is feasible to be used in the context of real-time traffic classification. Our experimental results show the distinct advantages of the proposed classification system, compared with the one-step Machine Learning (ML) approach.

  13. A Marine Traffic Flow Model

    OpenAIRE

    Tsz Leung Yip

    2013-01-01

    A model is developed for studying marine traffic flow through classical traffic flow theories, which can provide us with a better understanding of the phenomenon of traffic flow of ships. On one hand, marine traffic has its special features and is fundamentally different from highway, air and pedestrian traffic. The existing traffic models cannot be simply extended to marine traffic without addressing marine traffic features. On the other hand, existing literature on marine traffic focuses on...

  14. SELF-SIMILAR TRAFFIC GENERATOR

    OpenAIRE

    Linawati Linawati; I Made Suartika

    2009-01-01

    Network traffic generator can be produced using OPNET. OPNET generates the traffic as explicit traffic or background traffic. This paper demonstrates generating traffic in OPNET 7.0 as background traffic. The traffi generator that was simulated is self-similar traffic with different Hurst parameter. The simulation results proved that OPNET with background traffic function can be as a qualified self-similar traffic generator. These results can help in investigating and analysing network perfor...

  15. CK2 activity is required for the interaction of FGF14 with voltage-gated sodium channels and neuronal excitability.

    Science.gov (United States)

    Hsu, Wei-Chun J; Scala, Federico; Nenov, Miroslav N; Wildburger, Norelle C; Elferink, Hannah; Singh, Aditya K; Chesson, Charles B; Buzhdygan, Tetyana; Sohail, Maveen; Shavkunov, Alexander S; Panova, Neli I; Nilsson, Carol L; Rudra, Jai S; Lichti, Cheryl F; Laezza, Fernanda

    2016-06-01

    Recent data shows that fibroblast growth factor 14 (FGF14) binds to and controls the function of the voltage-gated sodium (Nav) channel with phenotypic outcomes on neuronal excitability. Mutations in the FGF14 gene in humans have been associated with brain disorders that are partially recapitulated in Fgf14(-/-) mice. Thus, signaling pathways that modulate the FGF14:Nav channel interaction may be important therapeutic targets. Bioluminescence-based screening of small molecule modulators of the FGF14:Nav1.6 complex identified 4,5,6,7 -: tetrabromobenzotriazole (TBB), a potent casein kinase 2 (CK2) inhibitor, as a strong suppressor of FGF14:Nav1.6 interaction. Inhibition of CK2 through TBB reduces the interaction of FGF14 with Nav1.6 and Nav1.2 channels. Mass spectrometry confirmed direct phosphorylation of FGF14 by CK2 at S228 and S230, and mutation to alanine at these sites modified FGF14 modulation of Nav1.6-mediated currents. In 1 d in vitro hippocampal neurons, TBB induced a reduction in FGF14 expression, a decrease in transient Na(+) current amplitude, and a hyperpolarizing shift in the voltage dependence of Nav channel steady-state inactivation. In mature neurons, TBB reduces the axodendritic polarity of FGF14. In cornu ammonis area 1 hippocampal slices from wild-type mice, TBB impairs neuronal excitability by increasing action potential threshold and lowering firing frequency. Importantly, these changes in excitability are recapitulated in Fgf14(-/-) mice, and deletion of Fgf14 occludes TBB-dependent phenotypes observed in wild-type mice. These results suggest that a CK2-FGF14 axis may regulate Nav channels and neuronal excitability.-Hsu, W.-C. J., Scala, F., Nenov, M. N., Wildburger, N. C., Elferink, H., Singh, A. K., Chesson, C. B., Buzhdygan, T., Sohail, M., Shavkunov, A. S., Panova, N. I., Nilsson, C. L., Rudra, J. S., Lichti, C. F., Laezza, F. CK2 activity is required for the interaction of FGF14 with voltage-gated sodium channels and neuronal

  16. A Survey on the Common Network Traffic Sources Models

    Directory of Open Access Journals (Sweden)

    Ahmed M. Mohammed

    2011-05-01

    Full Text Available Selecting the appropriate traffic model can lead to successful design of computer networks. Themore accurate the traffic model is the better the system quantified in terms of its performance.Successful design leads to enhancement the overall performance of the whole of network. Inliterature, there is innumerous traffic models proposed for understanding and analyzing the trafficcharacteristics of computer networks. Consequently, the study of traffic models to understand thefeatures of the models and identify eventually the best traffic model, for a concerned environmenthas become a crucial and lucrative task. Good traffic modeling is also a basic requirement foraccurate capacity planning. This paper provides an overview of some of the widely used networktraffic models, highlighting the core features of these models and traffic characteristics. Finally wefound that the N_BURST traffic model can capture the traffic characteristics of most types ofcomputer networks.

  17. Activation of L-type calcium channels is required for gap junction-mediated intercellular calcium signaling in osteoblastic cells

    Science.gov (United States)

    Jorgensen, Niklas Rye; Teilmann, Stefan Cuoni; Henriksen, Zanne; Civitelli, Roberto; Sorensen, Ole Helmer; Steinberg, Thomas H.

    2003-01-01

    The propagation of mechanically induced intercellular calcium waves (ICW) among osteoblastic cells occurs both by activation of P2Y (purinergic) receptors by extracellular nucleotides, resulting in "fast" ICW, and by gap junctional communication in cells that express connexin43 (Cx43), resulting in "slow" ICW. Human osteoblastic cells transmit intercellular calcium signals by both of these mechanisms. In the current studies we have examined the mechanism of slow gap junction-dependent ICW in osteoblastic cells. In ROS rat osteoblastic cells, gap junction-dependent ICW were inhibited by removal of extracellular calcium, plasma membrane depolarization by high extracellular potassium, and the L-type voltage-operated calcium channel inhibitor, nifedipine. In contrast, all these treatments enhanced the spread of P2 receptor-mediated ICW in UMR rat osteoblastic cells. Using UMR cells transfected to express Cx43 (UMR/Cx43) we confirmed that nifedipine sensitivity of ICW required Cx43 expression. In human osteoblastic cells, gap junction-dependent ICW also required activation of L-type calcium channels and influx of extracellular calcium.

  18. An efficient method to detect periodic behavior in botnet traffic by analyzing control plane traffic

    Science.gov (United States)

    AsSadhan, Basil; Moura, José M.F.

    2013-01-01

    Botnets are large networks of bots (compromised machines) that are under the control of a small number of bot masters. They pose a significant threat to Internet’s communications and applications. A botnet relies on command and control (C2) communications channels traffic between its members for its attack execution. C2 traffic occurs prior to any attack; hence, the detection of botnet’s C2 traffic enables the detection of members of the botnet before any real harm happens. We analyze C2 traffic and find that it exhibits a periodic behavior. This is due to the pre-programmed behavior of bots that check for updates to download them every T seconds. We exploit this periodic behavior to detect C2 traffic. The detection involves evaluating the periodogram of the monitored traffic. Then applying Walker’s large sample test to the periodogram’s maximum ordinate in order to determine if it is due to a periodic component or not. If the periodogram of the monitored traffic contains a periodic component, then it is highly likely that it is due to a bot’s C2 traffic. The test looks only at aggregate control plane traffic behavior, which makes it more scalable than techniques that involve deep packet inspection (DPI) or tracking the communication flows of different hosts. We apply the test to two types of botnet, tinyP2P and IRC that are generated by SLINGbot. We verify the periodic behavior of their C2 traffic and compare it to the results we get on real traffic that is obtained from a secured enterprise network. We further study the characteristics of the test in the presence of injected HTTP background traffic and the effect of the duty cycle on the periodic behavior. PMID:25685512

  19. Traffic Flow Theory

    OpenAIRE

    Maerivoet, Sven; De Moor, Bart

    2005-01-01

    The scientific field of traffic engineering encompasses a rich set of mathematical techniques, as well as researchers with entirely different backgrounds. This paper provides an overview of what is currently the state-of-the-art with respect to traffic flow theory. Starting with a brief history, we introduce the microscopic and macroscopic characteristics of vehicular traffic flows. Moving on, we review some performance indicators that allow us to assess the quality of traffic operations. A f...

  20. Optimizing Traffic Flow

    OpenAIRE

    Huberman, Bernardo A.; Helbing, Dirk

    1998-01-01

    We present an economics-based method for deciding the optimal rates at which vehicles are allowed to enter a highway. The method exploits the naturally occuring fluctuations of traffic flow and is flexible enough to adapt in real time to the transient flow characteristics of road traffic. Simulations based on realistic parameter values show that this strategy is feasible for naturally occuring traffic, and that even far from optimality, injection policies can improve traffic flow. Our results...

  1. Traffic-flow simulation

    OpenAIRE

    OMAHEN, ANDRAŽ

    2015-01-01

    This diploma thesis presents the behavior of program, which uses the traffic light enhanced transport network to simulate the traffic flow of vehicles that behave according to the IDM model. We upgraded the program to allow, for the given network, to optimize the traffic flow. Because of the overwhelming problem of road closures or their rearrangement, we added a graphical user interface with which a user can create or modify the road network to observe changes in traffic. The objective of...

  2. The H-loop in the Second Nucleotide-binding Domain of the Cystic Fibrosis Transmembrane Conductance Regulator is Required for Efficient Chloride Channel Closing

    OpenAIRE

    Kloch, Monika; Milewski, Michał; Nurowska, Ewa; Dworakowska, Beata; Cutting, Garry R; Dołowy, Krzysztof

    2010-01-01

    The cystic fibrosis transmembrane conductance regulator (CFTR) is an ATP-binding cassette (ABC) transporter that functions as a cAMP-activated chloride channel. The recent model of CFTR gating predicts that the ATP binding to both nucleotide-binding domains (NBD1 and NBD2) of CFTR is required for the opening of the channel, while the ATP hydrolysis at NBD2 induces subsequent channel closing. In most ABC proteins, efficient hydrolysis of ATP requires the presence of the invariant histidine res...

  3. Traffic Flow Estimates.

    Science.gov (United States)

    Hart, Vincent G.

    1981-01-01

    Two examples are given of ways traffic engineers estimate traffic flow. The first, Floating Car Method, involves some basic ideas and the notion of relative velocity. The second, Maximum Traffic Flow, is viewed to involve simple applications of calculus. The material provides insight into specialized applications of mathematics. (MP)

  4. Development and Evaluation of a Control System for Regional Traffic Management

    OpenAIRE

    McLin, John L.; William T. Scherer

    2011-01-01

    Traffic congestion is a worsening problem in metropolitan areas which will require integrated regional traffic control systems to improve traffic conditions. This paper presents a regional traffic control system which can detect incident conditions and provide integrated traffic management during nonrecurrent congestion events. The system combines advanced artificial intelligence techniques with a traffic performance model based on HCM equations. Preliminary evaluation of the control system u...

  5. Drosophila TRPA1 channel is required to avoid the naturally occurring insect repellent citronellal

    OpenAIRE

    Kwon, Young; Kim, Sang Hoon; Ronderos, David S.; Lee, Youngseok; Akitake, Bradley; Woodward, Owen M.; Guggino, William B.; Smith, Dean P.; Montell, Craig

    2010-01-01

    Plants produce naturally occurring insect repellents, such as citronellal, which is the main component of citronellal oil and is among the most widely-used-naturally-occurring insect repellents. However, the molecular pathways through which insects sense botanical repellents are unknown. Here, we showed that Drosophila used two pathways for direct avoidance of citronellal. The olfactory co-receptor, Or83b, which is required for the response to the synthetic repellent DEET, contributed to citr...

  6. Learning Behavior Models for Interpreting and Predicting Traffic Situations

    OpenAIRE

    Gindele, Tobias

    2014-01-01

    In this thesis, we present Bayesian state estimation and machine learning methods for predicting traffic situations. The cognitive ability to assess situations and behaviors of traffic participants, and to anticipate possible developments is an essential requirement for several applications in the traffic domain, especially for self-driving cars. We present a method for learning behavior models from unlabeled traffic observations and develop improved learning methods for decision trees.

  7. Measures related to traffic planning for air pollution control

    Energy Technology Data Exchange (ETDEWEB)

    Baumueller, J.; Reuter, U. [Office of Environmental Protection, Stuttgart (Germany). Dept. for Climatology

    1995-12-31

    The immense increase of motor traffic, in the future reinforced by the European market and the opening of boarders to the east countries, requires new efforts in traffic policy. In the city agglomerations the motor traffic is nearly collapsing. The increase of motor traffic is the reason for a considerable degradation of environment, especially by noise and air pollution. For the region of Stuttgart the problems and possibilities of counter-measures are discussed. (author)

  8. Traffic Square Management System

    OpenAIRE

    Sujata V. Padole

    2013-01-01

    If the traffic is more on one side and less on other side so there all way a waste of time and fuel on the traffic signal. Which is serious problem now day so there an need to have an intelligent traffic system which can detect the amount of traffic and make the change accordingly by using sensor and tranducer. Also by using motion detection camera at the lane we can find out the vehicle owner who break the traffic rules at the signal.

  9. Modelling the Traffic System

    Directory of Open Access Journals (Sweden)

    Važan Pavel

    2014-12-01

    Full Text Available The paper presents the simulation study results of the traffic system in the city of Hlohovec. The authors describe the process of building the model in Witness 2013c simulator. The individual entities of simulation model are explained in details, as the Witness simulator is primarily suitable for manufacture or service simulation and not for traffic system simulation. The goal of this paper is to analyse the traffic system and to suggest the changes for improving the traffic in the city of Hlohovec. All proposed measures will bring about 20% improvement of traffic when compared to the current state.

  10. Implementation of operational concept of air traffic

    OpenAIRE

    О.Є. Луппо; Ю.В. Чинченко

    2008-01-01

     Parameters of air traffic management, which influence safety, efficiency and regularity of flight are considered. Influence of required parameters of full system to total quality of operation of aeronautical system of Ukraine areanalyzed.

  11. Traffic Management Systems Performance Measurement: Final Report

    OpenAIRE

    Banks, James H.; Kelly, Gregory

    1997-01-01

    This report documents a study of performance measurement for Transportation Management Centers (TMCs). Performance measurement requirements were analyzed, data collection and management techniques were investigated, and case study traffic data system improvement plans were prepared for two Caltrans districts.

  12. A digital simulation of message traffic for natural disaster warning communications satellite

    Science.gov (United States)

    Hein, G. F.; Stevenson, S. M.

    1972-01-01

    Various types of weather communications are required to alert industries and the general public about the impending occurrence of tornados, hurricanes, snowstorms, floods, etc. A natural disaster warning satellite system has been proposed for meeting the communications requirements of the National Oceanic and Atmospheric Administration. Message traffic for a communications satellite was simulated with a digital computer in order to determine the number of communications channels to meet system requirements. Poisson inputs are used for arrivals and an exponential distribution is used for service.

  13. Implications of traffic characteristics on interdomain traffic engineering

    OpenAIRE

    Uhlig, Steve

    2004-01-01

    This thesis discusses the implications of the traffic characteristics on interdomain traffic engineering with BGP. We first provide an overview of the interdomain traffic control problem. Then, we present results concerning the characteristics of the interdomain traffic, based on the analysis of real traffic traces gathered from non-transit ASes. We discuss the implications of the topological properties of the traffic on interdomain traffic engineering. Based on this knowledge of the...

  14. Impact of Traffic Sign on Pedestrians’ Walking Behavior

    OpenAIRE

    Hui Xiong; Pingfu Yao; Xuedong Guo; Chenglong Chu; Wuhong Wang

    2015-01-01

    To study the impact of traffic sign on pedestrian walking behavior, the paper applies cellular automaton to simulate one-way pedestrian flow. The channel is defined as a rectangle with one open entrance and two exits of equal width. Traffic sign showing that exit is placed with some distance in the middle front of the two exits. In the simulation, walking environment is set with various input density, width of exit, width and length of the channel, and distance of the traffic sign to exit. Si...

  15. Study on Rural Poverty Reduction Effect of Traffic Infrastructure

    Institute of Scientific and Technical Information of China (English)

    Junping; GUO; Bin; ZHANG; Xiyan; ZHANG

    2014-01-01

    To systematically comb and explore the rural poverty reduction effect of traffic infrastructure,the author analyzed the mechanism,main channels and actual effect of rural traffic infrastructure on poverty reduction.It revealed that rural traffic infrastructure exerts positive or negative effect on poverty reduction directly or indirectly.The positive channel includes increasing non-agricultural employment opportunities,reducing costs for agricultural production,transportation and labor transfer,increasing availability of social service,and promoting adjustment of agricultural industrial structure and development of rural tourism resources.On the whole,traffic infrastructure has significant positive influence on rural poverty reduction.Finally,it summarized policy recommendations for building pro-poor traffic infrastructure,and came up with vacancy of related research field and future exploration direction.

  16. Costs of traffic injuries

    DEFF Research Database (Denmark)

    Kruse, Marie

    2015-01-01

    OBJECTIVE: The aim of this study was to analyse the socioeconomic costs of traffic injuries in Denmark, notably the healthcare costs and the productivity costs related to traffic injuries, in a bottom-up, register-based perspective. METHOD: Traffic injury victims were identified using national...... emergency room data and police records. Victims were matched with five controls per case by means of propensity score, nearest-neighbour matching. In the cohort, consisting of the 52 526 individuals that experienced a traffic injury in 2000 and 262 630 matched controls, attributable healthcare costs were...... assessed using Danish national healthcare registers. Productivity costs were computed using duration analysis (Cox regression models). In a subanalysis, cost per severe traffic injury was computed for the 12 995 individuals that experienced a severe injury. RESULTS: The socioeconomic cost of a traffic...

  17. Trajectory Based Traffic Analysis

    DEFF Research Database (Denmark)

    Krogh, Benjamin Bjerre; Andersen, Ove; Lewis-Kelham, Edwin;

    2013-01-01

    We present the INTRA system for interactive path-based traffic analysis. The analyses are developed in collaboration with traffic researchers and provide novel insights into conditions such as congestion, travel-time, choice of route, and traffic-flow. INTRA supports interactive point-and-click a......We present the INTRA system for interactive path-based traffic analysis. The analyses are developed in collaboration with traffic researchers and provide novel insights into conditions such as congestion, travel-time, choice of route, and traffic-flow. INTRA supports interactive point......-and-click analysis, due to a novel and efficient indexing structure. With the web-site daisy.aau.dk/its/spqdemo/we will demonstrate several analyses, using a very large real-world data set consisting of 1.9 billion GPS records (1.5 million trajectories) recorded from more than 13000 vehicles, and touching most of...

  18. Multicast traffic grooming in flexible optical WDM networks

    Science.gov (United States)

    Patel, Ankitkumar N.; Ji, Philip N.; Jue, Jason P.; Wang, Ting

    2012-12-01

    In Metropolitan Area Networks (MANs), point-to-multipoint applications, such as IPTV, video-on-demand, distance learning, and content distribution, can be efficiently supported through light-tree-based multicastcommunications instead of lightpath-based unicast-communications. The application of multicasting for such traffic is justified by its inherent benefits of reduced control and management overhead and elimination of redundant resource provisioning. Supporting such multicast traffic in Flexible optical WDM (FWDM) networks that can provision light-trees using optimum amount of spectrum within flexible channel spacing leads to higher wavelength and spectral efficiencies compared to the conventional ITU-T fixed grid networks. However, in spite of such flexibility, the residual channel capacity of stranded channels may not be utilized if the network does not offer channels with arbitrary line rates. Additionally, the spectrum allocated to guard bands used to isolate finer granularity channels remains unutilized. These limitations can be addressed by using traffic grooming in which low-rate multicast connections are aggregated and switched over high capacity light-trees. In this paper, we address the multicast traffic grooming problem in FWDM networks, and propose a novel auxiliary graph-based algorithm for the first time. The performance of multicast traffic grooming is evaluated in terms of spectral, cost, and energy efficiencies compared to lightpath-based transparent FWDM networks, lightpathbased traffic grooming-capable FWDM networks, multicast-enabled transparent FWDM networks, and multicast traffic grooming-capable fixed grid networks. Simulation results demonstrate that multicast traffic grooming in FWDM networks not only improves spectral efficiency, but also cost, and energy efficiencies compared to other multicast traffic provisioning approaches of FWDM and fixed grid networks.

  19. Internet Traffic Engineering

    OpenAIRE

    Bonaventure, Olivier; Trimintzios, Panos; Pavlou, George; Quoitin, Bruno; Azcorra, Arturo; Bagnulo, Marcelo; Fegkas, Paris; García-Martínez, Alberto; Georgatsos, Panos; Georgiadis, Leonidas; Jacquenet, Christian; Swinnen, Louis; Tandel, Sebastien; Uhlig, Steve

    2004-01-01

    Traffic engineering encompasses a set of techniques that can be used to control the flow of traffic in data networks. We discuss several of those techniques that have been developed during the last few years. Some techniques are focused on pure IP networks while others have been designed with emerging technologies for scalable Quality of Service (QoS) such as Differentiated Services and MPLS in mind. We first discuss traffic engineering techniques inside a single domain. We show that by using...

  20. Distraction in traffic.

    OpenAIRE

    2013-01-01

    Many drivers, as well as cyclists and pedestrians, are occupied with all kinds of activities that can distract their attention from traffic, like listening to music, conducting a conversation on their mobile phone, or texting. Distraction has negative effects on traffic behaviour. Most studies estimate that distraction plays a role in the occurrence of about 5-25% of the car crashes. Considering the increasing diffusion of electronic devices in traffic, portable media devices as well as advan...

  1. Traffic Congestion and Accidents

    OpenAIRE

    Schrage, Andrea

    2006-01-01

    Obstructions caused by accidents can trigger or exacerbate traffic congestion. This paper derives the efficient traffic pattern for a rush hour with congestion and accidents and the corresponding road toll. Compared to the model without accidents, where the toll equals external costs imposed on drivers using the road at the same time, a new insight arises: An optimal toll also internalizes the expected increase in future congestion costs. Since accidents affect more drivers if traffic volumes...

  2. Traffic Signs Inventory System

    Directory of Open Access Journals (Sweden)

    J. Ružbarský

    2013-06-01

    Full Text Available The paper is focused on practical application of Cambridge Correlator. The goal is to propose a traffic signs inventory system by using excellent characteristics of correlator in the rapid optical correlation. The proposal of this inventory system includes obtaining of traffic signs to create the database either collecting the GPS coordinates. It is necessary to know the traffic signs position and also to document the entire surface route for later evaluation in offline mode.

  3. Network Traffic Anomaly Detection

    OpenAIRE

    Huang, Hong; Al-Azzawi, Hussein; Brani, Hajar

    2014-01-01

    This paper presents a tutorial for network anomaly detection, focusing on non-signature-based approaches. Network traffic anomalies are unusual and significant changes in the traffic of a network. Networks play an important role in today's social and economic infrastructures. The security of the network becomes crucial, and network traffic anomaly detection constitutes an important part of network security. In this paper, we present three major approaches to non-signature-based network detect...

  4. Traffic Flow Management System

    Data.gov (United States)

    Department of Transportation — TFMS is a set NAS operational tools that predict demand, identify constraints, and facilitates collaboration among NAS users to support efficient traffic flow while...

  5. Subjective safety in traffic.

    OpenAIRE

    2012-01-01

    The term ‘subjective safety in traffic’ refers to people feeling unsafe in traffic or, more generally, to anxiety regarding being unsafe in traffic for oneself and/or others. Subjective safety in traffic can lead to road users limiting their mobility and social activities, which is one of the reasons it warrants policy-related attention. However, research has shown that, at most, there is a weak link between objective and subjective safety in traffic. There are even indications that some subj...

  6. Using memory for prior aircraft events to detect conflicts under conditions of proactive air traffic control and with concurrent task requirements.

    Science.gov (United States)

    Bowden, Vanessa K; Loft, Shayne

    2016-06-01

    In 2 experiments we examined the impact of memory for prior events on conflict detection in simulated air traffic control under conditions where individuals proactively controlled aircraft and completed concurrent tasks. Individuals were faster to detect conflicts that had repeatedly been presented during training (positive transfer). Bayesian statistics indicated strong evidence for the null hypothesis that conflict detection was not impaired for events that resembled an aircraft pair that had repeatedly come close to conflicting during training. This is likely because aircraft altitude (the feature manipulated between training and test) was attended to by participants when proactively controlling aircraft. In contrast, a minor change to the relative position of a repeated nonconflicting aircraft pair moderately impaired conflict detection (negative transfer). There was strong evidence for the null hypothesis that positive transfer was not impacted by dividing participant attention, which suggests that part of the information retrieved regarding prior aircraft events was perceptual (the new aircraft pair "looked" like a conflict based on familiarity). These findings extend the effects previously reported by Loft, Humphreys, and Neal (2004), answering the recent strong and unanimous calls across the psychological science discipline to formally establish the robustness and generality of previously published effects. (PsycINFO Database Record PMID:27295467

  7. Mathematical Modelling of Network Traffic

    OpenAIRE

    Li, Yu

    2015-01-01

    ncreasing access to the Internet is producing profound influence around the World. More and more people are taking advantage of the Internet to obtain information, communicate with each other far away and enjoy various recreations. This largely increased demand for the Internet requires better and more effective models. During the 1990s, a number of studies show that due to a different nature from telephonic traffic, in particular a bursty nature, traditional queuing models are not applicable...

  8. Pannexin1 Channels Are Required for Chemokine-Mediated Migration of CD4+ T Lymphocytes: Role in Inflammation and Experimental Autoimmune Encephalomyelitis.

    Science.gov (United States)

    Velasquez, Stephani; Malik, Shaily; Lutz, Sarah E; Scemes, Eliana; Eugenin, Eliseo A

    2016-05-15

    Pannexin1 (Panx1) channels are large high conductance channels found in all vertebrates that can be activated under several physiological and pathological conditions. Our published data indicate that HIV infection results in the extended opening of Panx1 channels (5-60 min), allowing for the secretion of ATP through the channel pore with subsequent activation of purinergic receptors, which facilitates HIV entry and replication. In this article, we demonstrate that chemokines, which bind CCR5 and CXCR4, especially SDF-1α/CXCL12, result in a transient opening (peak at 5 min) of Panx1 channels found on CD4(+) T lymphocytes, which induces ATP secretion, focal adhesion kinase phosphorylation, cell polarization, and subsequent migration. Increased migration of immune cells is key for the pathogenesis of several inflammatory diseases including multiple sclerosis (MS). In this study, we show that genetic deletion of Panx1 reduces the number of the CD4(+) T lymphocytes migrating into the spinal cord of mice subjected to experimental autoimmune encephalomyelitis, an animal model of MS. Our results indicate that opening of Panx1 channels in response to chemokines is required for CD4(+) T lymphocyte migration, and we propose that targeting Panx1 channels could provide new potential therapeutic approaches to decrease the devastating effects of MS and other inflammatory diseases. PMID:27076682

  9. The Traffic Light Challenge

    Science.gov (United States)

    Roman, Harry T.

    2014-01-01

    Traffic lights are an important part of the transportation infrastructure, regulating traffic flow and maintaining safety when crossing busy streets. When they go awry or become nonfunctional, a great deal of havoc and danger can be present. During power outages, the street lights go out all over the affected area. It would be good to be able to…

  10. Distraction in traffic.

    NARCIS (Netherlands)

    2013-01-01

    Many drivers, as well as cyclists and pedestrians, are occupied with all kinds of activities that can distract their attention from traffic, like listening to music, conducting a conversation on their mobile phone, or texting. Distraction has negative effects on traffic behaviour. Most studies estim

  11. Road Traffic in China

    NARCIS (Netherlands)

    Jie, L.; Van Zuylen, H.J.

    2014-01-01

    Traffic is tightly related to the social and economic development in a country. In China the development of the economy has been very fast in the past 30 years and this is still continuing. The transport infrastructure shows a similar pattern, while traffic is also rapidly growing. In urban areas th

  12. Controlled Traffic Farming

    OpenAIRE

    Controlled Traffic Farming Europe

    2011-01-01

    Metadata only record Controlled Traffic Farming (CTF) is a farming method used to reduce soil compaction, decrease inputs, and improve soil structure when coupled with reduced-till or no-till practices. This practices utilizes permanent traffic/wheel zones to limit soil compaction to a specific area. This website provides practical information on CTF, case studies, workshops, and links to additional resources.

  13. Visualization of Traffic Accidents

    Science.gov (United States)

    Wang, Jie; Shen, Yuzhong; Khattak, Asad

    2010-01-01

    Traffic accidents have tremendous impact on society. Annually approximately 6.4 million vehicle accidents are reported by police in the US and nearly half of them result in catastrophic injuries. Visualizations of traffic accidents using geographic information systems (GIS) greatly facilitate handling and analysis of traffic accidents in many aspects. Environmental Systems Research Institute (ESRI), Inc. is the world leader in GIS research and development. ArcGIS, a software package developed by ESRI, has the capabilities to display events associated with a road network, such as accident locations, and pavement quality. But when event locations related to a road network are processed, the existing algorithm used by ArcGIS does not utilize all the information related to the routes of the road network and produces erroneous visualization results of event locations. This software bug causes serious problems for applications in which accurate location information is critical for emergency responses, such as traffic accidents. This paper aims to address this problem and proposes an improved method that utilizes all relevant information of traffic accidents, namely, route number, direction, and mile post, and extracts correct event locations for accurate traffic accident visualization and analysis. The proposed method generates a new shape file for traffic accidents and displays them on top of the existing road network in ArcGIS. Visualization of traffic accidents along Hampton Roads Bridge Tunnel is included to demonstrate the effectiveness of the proposed method.

  14. Requirement of subunit co-assembly and ankyrin-G for M-channel localization at the axon initial segment

    DEFF Research Database (Denmark)

    Rasmussen, Hanne B; Frøkjaer-Jensen, Christian; Jensen, Camilla Stampe;

    2007-01-01

    The potassium channel subunits KCNQ2 and KCNQ3 are believed to underlie the M current of hippocampal neurons. The M-type potassium current plays a key role in the regulation of neuronal excitability; however, the subcellular location of the ion channels underlying this regulation has been controv...

  15. Slack sodium-activated potassium channel membrane expression requires p38 mitogen-activated protein kinase phosphorylation.

    Science.gov (United States)

    Gururaj, Sushmitha; Fleites, John; Bhattacharjee, Arin

    2016-04-01

    p38 MAPK has long been understood as an inducible kinase under conditions of cellular stress, but there is now increasing evidence to support its role in the regulation of neuronal function. Several phosphorylation targets have been identified, an appreciable number of which are ion channels, implicating the possible involvement of p38 MAPK in neuronal excitability. The KNa channel Slack is an important protein to be studied as it is highly and ubiquitously expressed in DRG neurons and is important in the maintenance of their firing accommodation. We sought to examine if the Slack channel could be a substrate of p38 MAPK activity. First, we found that the Slack C-terminus contains two putative p38 MAPK phosphorylation sites that are highly conserved across species. Second, we show via electrophysiology experiments that KNa currents and further, Slack currents, are subject to tonic modulation by p38 MAPK. Third, biochemical approaches revealed that Slack channel regulation by p38 MAPK occurs through direct phosphorylation at the two putative sites of interaction, and mutating both sites prevented surface expression of Slack channels. Based on these results, we conclude that p38 MAPK is an obligate regulator of Slack channel function via the trafficking of channels into the membrane. The present study identifies Slack KNa channels as p38 MAPK substrates. PMID:26721627

  16. The L-type calcium channel Cav1.3 is required for proper hippocampal neurogenesis and cognitive functions.

    Science.gov (United States)

    Marschallinger, Julia; Sah, Anupam; Schmuckermair, Claudia; Unger, Michael; Rotheneichner, Peter; Kharitonova, Maria; Waclawiczek, Alexander; Gerner, Philipp; Jaksch-Bogensperger, Heidi; Berger, Stefan; Striessnig, Jörg; Singewald, Nicolas; Couillard-Despres, Sebastien; Aigner, Ludwig

    2015-12-01

    L-type voltage gated Ca(2+) channels (LTCCs) are widely expressed within different brain regions including the hippocampus. The isoforms Cav1.2 and Cav1.3 have been shown to be involved in hippocampus-dependent learning and memory, cognitive functions that require proper hippocampal neurogenesis. In vitro, functional LTCCs are expressed on neuronal progenitor cells, where they promote neuronal differentiation. Expression of LTCCs on neural stem and progenitor cells within the neurogenic regions in the adult brain in vivo has not been examined so far, and a contribution of the individual isoforms Cav1.2 and Cav1.3 to adult neurogenesis remained to be clarified. To reveal the role of these channels we first evaluated the expression patterns of Cav1.2 and Cav1.3 in the hippocampal dentate gyrus and the subventricular zone (SVZ) in adult (2- and 3-month old) and middle-aged (15-month old) mice on mRNA and protein levels. We performed immunohistological analysis of hippocampal neurogenesis in adult and middle-aged Cav1.3(-/-) mice and finally addressed the importance of Cav1.3 for hippocampal function by evaluating spatial memory and depression-like behavior in adult Cav1.3(-/-) mice. Our results showed Cav1.2 and Cav1.3 expression at different stages of neuronal differentiation. While Cav1.2 was primarily restricted to mature NeuN(+) granular neurons, Cav1.3 was expressed in Nestin(+) neural stem cells and in mature NeuN(+) granular neurons. Adult and middle-aged Cav1.3(-/-) mice showed severe impairments in dentate gyrus neurogenesis, with significantly smaller dentate gyrus volume, reduced survival of newly generated cells, and reduced neuronal differentiation. Further, Cav1.3(-/-) mice showed impairment in the hippocampus dependent object location memory test, implicating Cav1.3 as an essential element for hippocampus-associated cognitive functions. Thus, modulation of LTCC activities may have a crucial impact on neurogenic responses and cognition, which should be

  17. A knowledge-based system for controlling automobile traffic

    Science.gov (United States)

    Maravas, Alexander; Stengel, Robert F.

    1994-01-01

    Transportation network capacity variations arising from accidents, roadway maintenance activity, and special events as well as fluctuations in commuters' travel demands complicate traffic management. Artificial intelligence concepts and expert systems can be useful in framing policies for incident detection, congestion anticipation, and optimal traffic management. This paper examines the applicability of intelligent route guidance and control as decision aids for traffic management. Basic requirements for managing traffic are reviewed, concepts for studying traffic flow are introduced, and mathematical models for modeling traffic flow are examined. Measures for quantifying transportation network performance levels are chosen, and surveillance and control strategies are evaluated. It can be concluded that automated decision support holds great promise for aiding the efficient flow of automobile traffic over limited-access roadways, bridges, and tunnels.

  18. Bayesian analysis of traffic flow on interstate I-55: The LWR model

    OpenAIRE

    Polson, Nicholas; Sokolov, Vadim

    2014-01-01

    Transportation departments take actions to manage traffic flow and reduce travel times based on estimated current and projected traffic conditions. Travel time estimates and forecasts require information on traffic density which are combined with a model to project traffic flow such as the Lighthill–Whitham–Richards (LWR) model. We develop a particle filtering and learning algorithm to estimate the current traffic density state and the LWR parameters. These inputs are related to the so-called...

  19. Market driven network neutrality and the fallacies of Internet traffic quality regulation

    OpenAIRE

    Knieps, Günter

    2011-01-01

    In the U.S. paying for priority arrangements between Internet access service providers and Internet application providers to favor some traffic over other traf-fic is considered unreasonable discrimination. In Europe the focus is on mini-mum traffic quality requirements. It can be shown that neither market power nor universal service arguments can justify traffic quality regulation. In particular, heterogeneous demand for traffic quality for delay sensitive versus delay insen-sitive applicati...

  20. Agent Based Individual Traffic Guidance

    DEFF Research Database (Denmark)

    Wanscher, Jørgen

    This thesis investigates the possibilities in applying Operations Research (OR) to autonomous vehicular traffic. The explicit difference to most other research today is that we presume that an agent is present in every vehicle - hence Agent Based Individual Traffic guidance (ABIT). The next...... that the system can be divided into two separate constituents. The immediate dispersion, which is used for small areas and quick response, and the individual alleviation, which considers the longer distance decision support. Both of these require intrinsicate models and cost functions which at the...... beginning of the project were not previously considered. We define a special inseparable cost function and develop a solution complex capable of using this cost function. In relation to calibration and estimation of statistical models used for dynamic route guidance we worked with generating random number...

  1. Traffic Flow Wide-Area Surveillance system

    Energy Technology Data Exchange (ETDEWEB)

    Allgood, G.O.; Ferrell, R.K.; Kercel, S.W.; Abston, R.A.

    1994-09-01

    Traffic management can be thought of as a stochastic queuing process where the serving time at one of its control points is dynamically linked to the global traffic pattern, which is, in turn, dynamically linked to the control point. For this closed-loop system to be effective, the traffic management system must sense and interpret a large spatial projection of data originating from multiple sensor suites. This concept is the basis for the development of a Traffic Flow Wide-Area Surveillance (TFWAS) system. This paper presents the results of a study by Oak Ridge National Laboratory to define the operational specifications and characteristics, to determine the constraints, and to examine the state of technology of a TFWAS system in terms of traffic management and control. In doing so, the functions and attributes of a TFWAS system are mapped into an operational structure consistent with the Intelligent Vehicle Highway System (IVHS) concept and the existing highway infrastructure. This mapping includes identifying candidate sensor suites and establishing criteria, requirements, and performance measures by which these systems can be graded in their ability and practicality to meet the operational requirements of a TFWAS system. In light of this, issues such as system integration, applicable technologies, impact on traffic management and control, and public acceptance are addressed.

  2. VBR video traffic models

    CERN Document Server

    Tanwir, Savera

    2014-01-01

    There has been a phenomenal growth in video applications over the past few years. An accurate traffic model of Variable Bit Rate (VBR) video is necessary for performance evaluation of a network design and for generating synthetic traffic that can be used for benchmarking a network. A large number of models for VBR video traffic have been proposed in the literature for different types of video in the past 20 years. Here, the authors have classified and surveyed these models and have also evaluated the models for H.264 AVC and MVC encoded video and discussed their findings.

  3. Road Traffic Injuries

    Institute of Scientific and Technical Information of China (English)

    WANG Zheng-guo

    2005-01-01

    @@ As everybody knows that automobiles have been greatly changing our life. However, everything has two sides, motor vehicles have also caused a huge number of people's deaths, injuries and property damage. Traffic crashes are perhaps the number one public health problem in developed countries [1]. In the United States, pre-retirement years of life lost in traffic crashes are more than that of the two combined leading diseases: cancer and heart disease [1]. Today road traffic crash (RTC) ranks 11th in leading cause of death and accounts for 2.1% of all deaths globally.

  4. Active plasmonics in WDM traffic switching applications

    OpenAIRE

    Sotirios Papaioannou; Dimitrios Kalavrouziotis; Konstantinos Vyrsokinos; Jean-Claude Weeber; Karim Hassan; Laurent Markey; Alain Dereux; Ashwani Kumar; Bozhevolnyi, Sergey I.; Matthias Baus; Tolga Tekin; Dimitrios Apostolopoulos; Hercules Avramopoulos; Nikos Pleros

    2012-01-01

    With metal stripes being intrinsic components of plasmonic waveguides, plasmonics provides a “naturally” energy-efficient platform for merging broadband optical links with intelligent electronic processing, instigating a great promise for low-power and small-footprint active functional circuitry. The first active Dielectric-Loaded Surface Plasmon Polariton (DLSPP) thermo-optic (TO) switches with successful performance in single-channel 10 Gb/s data traffic environments have led the inroad tow...

  5. Two dimensional mixed traffic flow considering the transit traffic

    OpenAIRE

    Lingjiang Kong; Junhui Hu; Li Yang

    2012-01-01

    Based on the two-dimension cellular automaton traffic flow model (BML model), a mixed traffic flow model for urban traffic considering the transit traffic is established in this paper by using the Don't block the box rules. We have investigated the influences of the transit traffic ratio, and found that, in most cases, the urban traffic flow exhibited jam phase. Moreover, focusing on the traffic lights cycle, it is found that the average flow has the periodic fluctuation phenomenon, and we ha...

  6. Energy-Efficient Relay Selection and Optimal Relay Location in Cooperative Cellular Networks with Asymmetric Traffic

    CERN Document Server

    Yang, Wei; Sun, Wanlu

    2010-01-01

    Energy-efficient communication is an important requirement for mobile relay networks due to the limited battery power of user terminals. This paper considers energy-efficient relaying schemes through selection of mobile relays in cooperative cellular systems with asymmetric traffic. The total energy consumption per information bit of the battery-powered terminals, i.e., the mobile station (MS) and the relay, is derived in theory. In the Joint Uplink and Downlink Relay Selection (JUDRS) scheme we proposed, the relay which minimizes the total energy consumption is selected. Additionally, the energy-efficient cooperation regions are investigated, and the optimal relay location is found for cooperative cellular systems with asymmetric traffic. The results reveal that the MS-relay and the relay-base station (BS) channels have different influence over relay selection decisions for optimal energy-efficiency. Information theoretic analysis of the diversity-multiplexing tradeoff (DMT) demonstrates that the proposed sc...

  7. Turning Traffic Jams to Jelly

    Institute of Scientific and Technical Information of China (English)

    LI LI

    2010-01-01

    @@ Beijing, known for having the worst traffic in China, is brewing up a traffic plan with the harshest ever measures to ensure smooth traffic flow as the capital's gridlock during rush hour and private car sales soar. On December 13, the Beijing Municipal Government started soliciting public opinions for a draft plan designed to relieve the city's traffic problems.

  8. Traffic-Adaptive Routing

    OpenAIRE

    Kammenhuber, Nils

    2011-01-01

    Despite the bursty and highly volatile traffic, routing in the Internet today is optimised only on coarse time scales, as load-adaptive routing is known to induce performance deterioration by causing massive oscillations. We describe ReplEx, an universally applicable distributed algorithm for dynamic routing/traffic engineering, which is based on game theory. We show through extensive realistic simulations that ReplEx does not oscillate, and that it achieves performance gains comparable to tr...

  9. Traffic engineering eye diagram

    OpenAIRE

    Kowalik, Karol; Collier, Martin

    2005-01-01

    It is said that a picture is worth a thousand words - this statement also applies to networking topics. Thus, to effectively monitor network performance we need tools which present the performance metrics in a graphical way which is also clear and informative. We propose a tool for this purpose which we call the traffic engineering eye diagram (TEED). Eye diagrams are used in digital communications to analyse the quality of a digital signal; the TEED can similarly he used in the traffic engin...

  10. Traffic Management Systems

    OpenAIRE

    Wei Chen; David Levinson

    2004-01-01

    This study uses regression analysis to evaluate long-run traffic management system performance. Three important traffic management systems in the Twin Cities metro area - Ramp Metering, Variable Message Signs (VMS), and Freeway Service Patrol (the Highway Helper Program) were evaluated with multiple regression models to predict link speed and incident rate. We find that ramp meters increase freeway link speed and reduce incident rate. Freeway Service Patrols increase link speed when incidents...

  11. Penalties in traffic.

    OpenAIRE

    2009-01-01

    Traffic offenders are penalized in various ways: fines, (temporary) driving licence suspensions, confiscation of their vehicles, penalty points, mandatory participation in rehabilitation programmes, prison sentences or community service. The aim of penalties is to punish offenders, to protect society and to influence the behaviour of offenders and all citizens (prevention). Many studies have found that the combination of enforcement and penalties prevent the violation of traffic regulations a...

  12. Accurate Multisteps Traffic Flow Prediction Based on SVM

    OpenAIRE

    Zhang Mingheng; Zhen Yaobao; Hui Ganglong; Chen Gang

    2013-01-01

    Accurate traffic flow prediction is prerequisite and important for realizing intelligent traffic control and guidance, and it is also the objective requirement for intelligent traffic management. Due to the strong nonlinear, stochastic, time-varying characteristics of urban transport system, artificial intelligence methods such as support vector machine (SVM) are now receiving more and more attentions in this research field. Compared with the traditional single-step prediction method, the mul...

  13. Designing areas and elements in traffic environment for disabled people

    OpenAIRE

    Markovič, Anja

    2011-01-01

    Traffic environment is one of the most dangerous areas in human's everyday because of interweaving between pedestrian's paths and traffic. Disabled people are even more undangered in this kind of areas. Graduation thesis describes elements and measures for designing traffic environment according to different types of human disability and their requirements with intention to build transitional and safe environment for everyone. It describes tehnical elements of designing areas and different ki...

  14. Ant traffic rules.

    Science.gov (United States)

    Fourcassié, Vincent; Dussutour, Audrey; Deneubourg, Jean-Louis

    2010-07-15

    Many animals take part in flow-like collective movements. In most species, however, the flow is unidirectional. Ants are one of the rare group of organisms in which flow-like movements are predominantly bidirectional. This adds to the difficulty of the task of maintaining a smooth, efficient movement. Yet, ants seem to fare well at this task. Do they really? And if so, how do such simple organisms succeed in maintaining a smooth traffic flow, when even humans experience trouble with this task? How does traffic in ants compare with that in human pedestrians or vehicles? The experimental study of ant traffic is only a few years old but it has already provided interesting insights into traffic organization and regulation in animals, showing in particular that an ant colony as a whole can be considered as a typical self-organized adaptive system. In this review we will show that the study of ant traffic can not only uncover basic principles of behavioral ecology and evolution in social insects but also provide new insights into the study of traffic systems in general. PMID:20581264

  15. RESEARCH OF ENGINEERING TRAFFIC IN COMPUTER UZ NETWORK USING MPLS TE TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    V. M. Pakhomovа

    2014-12-01

    Full Text Available Purpose. In railway transport of Ukraine one requires the use of computer networks of different technologies: Ethernet, Token Bus, Token Ring, FDDI and others. In combined computer networks on the railway transport it is necessary to use packet switching technology in multiprotocol networks MPLS (MultiProtocol Label Switching more effectively. They are based on the use of tags. Packet network must transmit different types of traffic with a given quality of service. The purpose of the research is development a methodology for determining the sequence of destination flows for the considered fragment of computer network of UZ. Methodology. When optimizing traffic management in MPLS networks has the important role of technology traffic engineering (Traffic Engineering, TE. The main mechanism of TE in MPLS is the use of unidirectional tunnels (MPLS TE tunnel to specify the path of the specified traffic. The mathematical model of the problem of traffic engineering in computer network of UZ technology MPLS TE was made. Computer UZ network is represented with the directed graph, their vertices are routers of computer network, and each arc simulates communication between nodes. As an optimization criterion serves the minimum value of the maximum utilization of the TE-tunnel. Findings. The six options destination flows were determined; rational sequence of flows was found, at which the maximum utilization of TE-tunnels considered a simplified fragment of a computer UZ network does not exceed 0.5. Originality. The method of solving the problem of traffic engineering in Multiprotocol network UZ technology MPLS TE was proposed; for different classes its own way is laid, depending on the bandwidth and channel loading. Practical value. Ability to determine the values of the maximum coefficient of use of TE-tunnels in computer UZ networks based on developed software model «TraffEng». The input parameters of the model: number of routers, channel capacity, the

  16. Massively parallel processor networks with optical express channels

    Science.gov (United States)

    Deri, R.J.; Brooks, E.D. III; Haigh, R.E.; DeGroot, A.J.

    1999-08-24

    An optical method for separating and routing local and express channel data comprises interconnecting the nodes in a network with fiber optic cables. A single fiber optic cable carries both express channel traffic and local channel traffic, e.g., in a massively parallel processor (MPP) network. Express channel traffic is placed on, or filtered from, the fiber optic cable at a light frequency or a color different from that of the local channel traffic. The express channel traffic is thus placed on a light carrier that skips over the local intermediate nodes one-by-one by reflecting off of selective mirrors placed at each local node. The local-channel-traffic light carriers pass through the selective mirrors and are not reflected. A single fiber optic cable can thus be threaded throughout a three-dimensional matrix of nodes with the x,y,z directions of propagation encoded by the color of the respective light carriers for both local and express channel traffic. Thus frequency division multiple access is used to hierarchically separate the local and express channels to eliminate the bucket brigade latencies that would otherwise result if the express traffic had to hop between every local node to reach its ultimate destination. 3 figs.

  17. A Cooperative Traffic Control Strategy

    OpenAIRE

    BORG, Dora Lee; Bhouri, Neila; SCERRI, Kenneth

    2015-01-01

    With one-third of the global population living in cities by 2030 and the need for mobility fueling traffic growth all over the world, the traffic congestion problem in major cities is becoming more and more acute. Besides economic losses, traffic congestion has detrimental effects on our standard of living and on the environment. A viable solution to the traffic congestion problem is intelligent traffic control. The main aim of this work is to test a Model Predictive Control Strategy (MPC) on...

  18. Traffic violation alert and management

    OpenAIRE

    Aliane, Nourdine; Fernández Andrés, Javier; Bemposta Rosende, Sergio; Mata Ortega, Mario

    2011-01-01

    The present paper presents an in-vehicle system for traffic violation alert and management. The system hardware consists of a combination of an on-board computer vision system for traffic sign detection and recognition with a data recorder device for traffic violation alert and management. At present, traffic violations are only focused on three signs: namely speed limit, stop sign, and forbidden turning. The system is designed to warn drivers about potential traffic violations by emitting ac...

  19. Traffic Information System for Hanoi

    OpenAIRE

    Sohr, Alexander; Brockfeld, Elmar; Sauerländer-Biebl, Anke; Melde, Eric

    2016-01-01

    To improve the traffic situation in Hanoi it is necessary to have a good overview of the existing traffic situation and to monitor the development of the traffic over longer time periods. Floating Car Data (FCD) Systems can help to acquire area wide traffic information; here a FCD system based on taxis, busses and motor-cycles is described. It consists of Web and App tools and a Hotspot-Monitoring for long term traffic analysis.

  20. Traffic Monitoring and Control Using RFID

    Directory of Open Access Journals (Sweden)

    Gaurav Thakur

    2013-09-01

    Full Text Available Traffic congestion and tidal flow management were recognized as major problems in modern urban areas, which have caused much frustration and loss of man hours. The operation of standard traffic lights which are currently deployed in many junctions, are based on predetermined timing schemes, which are fixed during the installation and remain until further resetting. The timing is no more than a default setup to control what may be considered as normal traffic. Although every road junction by necessity requires different traffic light timing setup, many existing systems operate with a default sequence. To design an intelligent and efficient traffic control system, a number of parameters that represent the status of the road conditions must be identified and taken into consideration. Approach: In order to solve the problem an intelligent RFID traffic control has been developed. This project is based on monitoring the traffic density at the signal using RFID Reader. RFID tags which is placed (instead of number plate at each vehicle will serve as the unique number of vehicle .Reader will count the number of tags at the signal and take decision of increasing or decreasing the signal time .This reader is also use to find the violation(VIN of violator of the signal. Each passive tag will have certain number of bytes information will be different for different vehicles. Whenever any tag will approach any signal, reader will take that bytes of information and simultaneously will also increment the number of vehicles for making decision to change the signal timing. Each tag of data will be stored in main memory (database.This unique data will also help in determining the violator of the signal .Thus it will save human efforts and resources to a greater extent and reduce waiting of the people at the signal. After implementation of this project, now all people waiting at the signal will get proper time (green light according to the traffic density

  1. Traffic management as a service: the traffic flow pattern classification problem

    OpenAIRE

    Carlos T. Calafate; David Soler; Juan-Carlos Cano; Pietro Manzoni

    2015-01-01

    Intelligent Transportation System (ITS) technologies can be implemented to reduce both fuel consumption and the associated emission of greenhouse gases. However, such systems require intelligent and effective route planning solutions to reduce travel time and promote stable traveling speeds. To achieve such goal these systems should account for both estimated and real-time traffic congestion states, but obtaining reliable traffic congestion estimations for all the streets/avenues in a city...

  2. Dystrophin is required for the normal function of the cardio-protective K(ATP channel in cardiomyocytes.

    Directory of Open Access Journals (Sweden)

    Laura Graciotti

    Full Text Available Duchenne and Becker muscular dystrophy patients often develop a cardiomyopathy for which the pathogenesis is still unknown. We have employed the murine animal model of Duchenne muscular dystrophy (mdx, which develops a cardiomyopathy that includes some characteristics of the human disease, to study the molecular basis of this pathology. Here we show that the mdx mouse heart has defects consistent with alteration in compounds that regulate energy homeostasis including a marked decrease in creatine-phosphate (PC. In addition, the mdx heart is more susceptible to anoxia than controls. Since the cardio-protective ATP sensitive potassium channel (K(ATP complex and PC have been shown to interact we investigated whether deficits in PC levels correlate with other molecular events including K(ATP ion channel complex presence, its functionality and interaction with dystrophin. We found that this channel complex is present in the dystrophic cardiac cell membrane but its ability to sense a drop in the intracellular ATP concentration and consequently open is compromised by the absence of dystrophin. We further demonstrate that the creatine kinase muscle isoform (CKm is displaced from the plasma membrane of the mdx cardiac cells. Considering that CKm is a determinant of K(ATP channel complex function we hypothesize that dystrophin acts as a scaffolding protein organizing the K(ATP channel complex and the enzymes necessary for its correct functioning. Therefore, the lack of proper functioning of the cardio-protective K(ATP system in the mdx cardiomyocytes may be part of the mechanism contributing to development of cardiac disease in dystrophic patients.

  3. Analysis of Dynamic Road Traffic Congestion Control (DRTCC Techniques

    Directory of Open Access Journals (Sweden)

    Pardeep Mittal

    2015-10-01

    Full Text Available : Dynamic traffic light control at intersection has become one of the most active research areas to develop the Dynamic transportation systems (ITS. Due to the consistent growth in urbanization and traffic congestion, such a system was required which can control the timings of traffic lights dynamically with accurate measurement of traffic on the road. In this paper, analysis of all the techniques that has been developed to automate the traffic lights has been done.. The efficacy of all the techniques has been evaluated, using MATLAB software. After comparison of artificial intelligent techniques , it is found that image mosaicking technique is quite effective (in terms of improving moving time and reducing waiting time for the control of the traffic signals to control congestion on the road.

  4. Molecular Motors and Apical CFTR Traffic in Epithelia

    Directory of Open Access Journals (Sweden)

    Dmitri V. Kravtsov

    2013-05-01

    Full Text Available Intracellular protein traffic plays an important role in the regulation of Cystic Fibrosis Transmembrane Conductance Regulator (CFTR chloride channels. Microtubule and actin-based motor proteins direct CFTR movement along trafficking pathways. As shown for other regulatory proteins such as adaptors, the involvement of protein motors in CFTR traffic is cell-type specific. Understanding motor specificity provides insight into the biology of the channel and opens opportunity for discovery of organ-specific drug targets for treating CFTR-mediated diseases.

  5. 14 CFR 298.61 - Reporting of traffic statistics.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Reporting of traffic statistics. 298.61... Requirements § 298.61 Reporting of traffic statistics. (a) Each commuter air carrier and small certificated air... statistics shall be compiled in terms of each flight stage as actually performed. The detail T-100 data...

  6. Emergent traffic jams

    CERN Document Server

    Nagel, K; Nagel, Kai; Paczuski, Maya

    1995-01-01

    We study a single-lane traffic model that is based on human driving behavior. The outflow from a traffic jam self-organizes to a critical state of maximum throughput. Small perturbations of the outflow far downstream create emergent traffic jams with a power law distribution P(t) \\sim t^{-3/2} of lifetimes, t. On varying the vehicle density in a closed system, this critical state separates lamellar and jammed regimes, and exhibits 1/f noise in the power spectrum. Using random walk arguments, in conjunction with a cascade equation, we develop a phenomenological theory that predicts the critical exponents for this transition and explains the self-organizing behavior. These predictions are consistent with all of our numerical results.

  7. Traffic Engineering in Metro Ethernet

    Directory of Open Access Journals (Sweden)

    Padmaraj Nair

    2010-05-01

    Full Text Available Traffic engineering is one of the major issues that has to be addressed in Metro Ethernet networks for quality of service and efficient resource utilization. This paper aims at understanding the relevant issues and outlines novel algorithms for multipoint traffic engineering in Metro Ethernet. We present an algorithmic solution for traffic engineering in Metro Ethernet using optimal multiple spanning trees. This iterative approach distributes traffic across the network uniformly without overloading network resources. We also introduce a new traffic specification model for Metro Ethernet, which is a hybrid of two widely used traffic specification models, the pipe and hose models.

  8. Phosphorylation of TRPC6 Channels at Thr69 Is Required for Anti-hypertrophic Effects of Phosphodiesterase 5 Inhibition*

    OpenAIRE

    Nishida, Motohiro; Watanabe, Kenta; Sato, Yoji; Nakaya, Michio; Kitajima, Naoyuki; Ide, Tomomi; Inoue, Ryuji; Kurose, Hitoshi

    2010-01-01

    Activation of Ca2+ signaling induced by receptor stimulation and mechanical stress plays a critical role in the development of cardiac hypertrophy. A canonical transient receptor potential protein subfamily member, TRPC6, which is activated by diacylglycerol and mechanical stretch, works as an upstream regulator of the Ca2+ signaling pathway. Although activation of protein kinase G (PKG) inhibits TRPC6 channel activity and cardiac hypertrophy, respectively, it is unclear whether PKG suppresse...

  9. Two dimensional mixed traffic flow considering the transit traffic

    Directory of Open Access Journals (Sweden)

    Lingjiang Kong

    2012-12-01

    Full Text Available Based on the two-dimension cellular automaton traffic flow model (BML model, a mixed traffic flow model for urban traffic considering the transit traffic is established in this paper by using the Don't block the box rules. We have investigated the influences of the transit traffic ratio, and found that, in most cases, the urban traffic flow exhibited jam phase. Moreover, focusing on the traffic lights cycle, it is found that the average flow has the periodic fluctuation phenomenon, and we have explained this periodical oscillation change under different boundary conditions. The comparison to practical measured data shows that our stimulation results are accordant with the changes of real traffic flow, which confirms the accuracy and rationality of our model.

  10. An analytical model of pipelined circuit switching in hypercubes in the presence of hot spot traffic

    OpenAIRE

    Safaei, F.; Khonsari, A.; Fathy, M.; Ould-Khaoua, M.

    2005-01-01

    Several recent studies have revealed that PCS can provide superior performance characteristics over wormhole switching under uniform traffic. Analytical model of PCS for common networks (e.g., hypercube) under uniform traffic pattern have recently been reported in the literature. In this paper we propose an analytical model of PCS in the hypercube network augmented with virtual channel in the presence of hot spot traffic. The model has a good agreement with simulation experiments.

  11. An online railway traffic prediction model

    NARCIS (Netherlands)

    Kecman, P.; Goverde, R.M.P.

    2013-01-01

    Prediction of train positions in time and space is required for traffic control and passenger information. However, in practice only the last measured train delays are known and dispatchers must predict the arrival times of trains without adequate computer support. This paper presents a real-time to

  12. Draft project for traffic monitoring by drones

    OpenAIRE

    Floch, E.; LESAGE, Y; SORIN, JL

    2004-01-01

    The implementation of the Road Traffic Information Master Plan (Schéma Directeur d'Information Routière or "SDIR"), on 20 000 km of strategic roads throughout the country and by 2010, is one of the main policies of the French Ministry of Transport. It has a particular impact on road safety issues. The SDIR aims to provide road users with reliable information on road traffic conditions, and requires major developments within the organisations in charge of road management, in addition to the im...

  13. Free Flight vs. Centralized Air Traffic Management

    OpenAIRE

    Octavian Thor PLETER; Bogdan DONCIU

    2011-01-01

    The current Air Traffic Management system is subject to structural changes, which are expected over the next 20 years.These changes are required for a number of reasons:The current system inflicts delays and fuel inefficiencies to flights (as demonstrated by the historic Paris-Miami Air France flight in April 2010)The current system has structural and operational capacity limitationsUnder current system, the complexity of the Air Traffic Controller’s work increases steeply with trafficVoi...

  14. Traffic Management as a Service: The Traffic Flow Pattern Classification Problem

    Directory of Open Access Journals (Sweden)

    Carlos T. Calafate

    2015-01-01

    Full Text Available Intelligent Transportation System (ITS technologies can be implemented to reduce both fuel consumption and the associated emission of greenhouse gases. However, such systems require intelligent and effective route planning solutions to reduce travel time and promote stable traveling speeds. To achieve such goal these systems should account for both estimated and real-time traffic congestion states, but obtaining reliable traffic congestion estimations for all the streets/avenues in a city for the different times of the day, for every day in a year, is a complex task. Modeling such a tremendous amount of data can be time-consuming and, additionally, centralized computation of optimal routes based on such time-dependencies has very high data processing requirements. In this paper we approach this problem through a heuristic to considerably reduce the modeling effort while maintaining the benefits of time-dependent traffic congestion modeling. In particular, we propose grouping streets by taking into account real traces describing the daily traffic pattern. The effectiveness of this heuristic is assessed for the city of Valencia, Spain, and the results obtained show that it is possible to reduce the required number of daily traffic flow patterns by a factor of 4210 while maintaining the essence of time-dependent modeling requirements.

  15. Traffic Light Detection

    DEFF Research Database (Denmark)

    Philipsen, Mark Philip; Jensen, Morten Bornø; Møgelmose, Andreas; Moeslund, Thomas B.; Trivedi, Mohan M.

    database is collected based on footage from US roads. The database consists of both test and training data, totaling 46,418 frames and 112,971 annotated traffic lights, captured in continuous sequences under a varying light and weather conditions. The learning based detector achieves an AUC of 0.4 and 0...

  16. An Adaptive Traffic Control System Using Raspberry PI

    Directory of Open Access Journals (Sweden)

    S.Lokesh *

    2014-06-01

    Full Text Available By increasing of population the usage of vehicles have been increasing and controlling of traffic is one of the challenging works. The frequent traffic jams at major junctions call for an efficient traffic management system in place. The resulting wastage of time and increase in pollution levels can be eliminated on a city-wide scale by these systems. Previously the traffic control techniques used like magnetic loop detectors, induction loop detectors are buried on the road side provide the limited traffic information and require separate systems for traffic counting and for traffic surveillance. Here the project proposes to implement an artificial density traffic control system using image processing and Raspberrypi. The hardware here we are using is webcam, pc, Raspberry pi and the software used is OCCIDENTALIS and MATLAB. In this project the camera is get interfaced with a Raspberry pi. The image sequences from a camera are analyzed using thresholding method to find the density of vehicles. Subsequently, the number of vehicles at the intersection is evaluated and traffic is efficiently managed. In this project we implemented a real-time emergency vehicle detection system. In case an emergency vehicle is detected, the lane is given priority over all the others.

  17. Distributed learning and multi-objectivity in traffic light control

    Science.gov (United States)

    Brys, Tim; Pham, Tong T.; Taylor, Matthew E.

    2014-01-01

    Traffic jams and suboptimal traffic flows are ubiquitous in modern societies, and they create enormous economic losses each year. Delays at traffic lights alone account for roughly 10% of all delays in US traffic. As most traffic light scheduling systems currently in use are static, set up by human experts rather than being adaptive, the interest in machine learning approaches to this problem has increased in recent years. Reinforcement learning (RL) approaches are often used in these studies, as they require little pre-existing knowledge about traffic flows. Distributed constraint optimisation approaches (DCOP) have also been shown to be successful, but are limited to cases where the traffic flows are known. The distributed coordination of exploration and exploitation (DCEE) framework was recently proposed to introduce learning in the DCOP framework. In this paper, we present a study of DCEE and RL techniques in a complex simulator, illustrating the particular advantages of each, comparing them against standard isolated traffic actuated signals. We analyse how learning and coordination behave under different traffic conditions, and discuss the multi-objective nature of the problem. Finally we evaluate several alternative reward signals in the best performing approach, some of these taking advantage of the correlation between the problem-inherent objectives to improve performance.

  18. Occupant traffic estimation through structural vibration sensing

    Science.gov (United States)

    Pan, Shijia; Mirshekari, Mostafa; Zhang, Pei; Noh, Hae Young

    2016-04-01

    The number of people passing through different indoor areas is useful in various smart structure applications, including occupancy-based building energy/space management, marketing research, security, etc. Existing approaches to estimate occupant traffic include vision-, sound-, and radio-based (mobile) sensing methods, which have placement limitations (e.g., requirement of line-of-sight, quiet environment, carrying a device all the time). Such limitations make these direct sensing approaches difficult to deploy and maintain. An indirect approach using geophones to measure floor vibration induced by footsteps can be utilized. However, the main challenge lies in distinguishing multiple simultaneous walkers by developing features that can effectively represent the number of mixed signals and characterize the selected features under different traffic conditions. This paper presents a method to monitor multiple persons. Once the vibration signals are obtained, features are extracted to describe the overlapping vibration signals induced by multiple footsteps, which are used for occupancy traffic estimation. In particular, we focus on analysis of the efficiency and limitations of the four selected key features when used for estimating various traffic conditions. We characterize these features with signals collected from controlled impulse load tests as well as from multiple people walking through a real-world sensing area. In our experiments, the system achieves the mean estimation error of +/-0.2 people for different occupant traffic conditions (from one to four) using k-nearest neighbor classifier.

  19. Traffic Engineering in Metro Ethernet

    OpenAIRE

    Padmaraj Nair; Suku Nair; Girish Chiruvolu

    2010-01-01

    Traffic engineering is one of the major issues that has to be addressed in Metro Ethernet networks for quality of service and efficient resource utilization. This paper aims at understanding the relevant issues and outlines novel algorithms for multipoint traffic engineering in Metro Ethernet. We present an algorithmic solution for traffic engineering in Metro Ethernet using optimal multiple spanning trees. This iterative approach distributes traffic across the network uniformly without overl...

  20. Traffic flow modeling: a Genealogy

    OpenAIRE

    Van Wageningen-Kessels, F.L.M.; Hoogendoorn, S.P.; Vuik, C.; Lint, van J. W. C.

    2014-01-01

    80 years ago, Bruce Greenshields presented the first traffic flow model at the Annual Meeting of the Highway Research Board. Since then, many models and simulation tools have been developed. We show a model tree with four families of traffic flow models, all descending from Greenshields' model. The tree shows the historical development of traffic flow modeling and the relations between models. Based on the tree we discuss the main trends and future developments in traffic flow modeling and si...

  1. Virtualized Traffic at Metropolitan Scales

    OpenAIRE

    Wilkie, David; Sewall, Jason; Li, Weizi; Lin, Ming C.

    2015-01-01

    Few phenomena are more ubiquitous than traffic in urban scenes, and few are more significant economically, socially, or environmentally. Many virtual-reality applications and systems, including virtual globes and immersive multi-player worlds that are often set in a large-scale modern or futuristic setting, feature traffic systems. Virtual-reality models can also aid in addressing the challenges of real-world traffic – the ever-present gridlock and congestion in cities worldwide: traffic engi...

  2. Road Traffic Accidents in Kazakhstan

    OpenAIRE

    Alma Aubakirova; Alibek Kossumov; Nurbek Igissinov

    2013-01-01

    Background: The article provides the analysis of death rates in road traffic accidents in Kazakhstan from 2004 to 2010 and explores the use of sanitary aviation. Methods: Data of fatalities caused by road traffic accidents were collected and analysed. Descriptive and analytical methods of epidemiology and biomedical statistics were applied. Results: Totaly 27,003 people died as a result of road traffic accidents in this period. The death rate for the total population due to road traffic accid...

  3. Coordination of traffic lights evaluation

    OpenAIRE

    Ordeig Vila, Enric

    2012-01-01

    This case study consists in the evaluation of the Kaunas city traffic speed taking into consideration that traffic lights were coordinated. Kaunas suffers from high traffic intensity and, as a consequence, traffic jams often, and happens mainly because the city can only be crossed by the center. Lithuania, as the rest of Europe experienced a big growth, from 1995 to 2005 coinciding with the crisis, that is to say that number of cars increased to highest levels as well as the ...

  4. Automated Traffic Enforcement in France

    OpenAIRE

    BRIQUET, Philippe; CANEL, A

    2002-01-01

    One of the goals of traffic safety in cities and between cities is to increase compliance with Traffic Regulations. For this purpose, the French Ministry of Transportation decided to set up an automated traffic enforcement program. This program currently focuses on several types of violations : speeding, spacing between vehicles, and traffic light and railway crossing. This article presents the main goals of the program and the expected challenges and characteristics of operations that have b...

  5. High Performance Hierarchical Torus Network Under Adverse Traffic Patterns

    Directory of Open Access Journals (Sweden)

    MM Hafizur Rahman

    2012-03-01

    Full Text Available A Hierarchical Torus Network (HTN is a 2D-torus network of multiple basic modules, in which the basic modules are 3D-torus networks that are hierarchically interconnected for higher level networks. The dynamic communication performance of the HTN using the dimension-order routing under common traffic patterns have been evaluated, and have been shown to be good. However, dynamic communication performance of HTN under adverse traffic patterns has not been evaluated yet. In this paper, we evaluate the dynamic communication performance of HTN using a deadlock-free dimension order routing with 3 virtual channels under adverse traffic patterns, and compare it with H3D-mesh, mesh, and torus networks. It is shown that even under adverse traffic patterns, the HTN yields high throughput and low average transfer time, which provide better dynamic communication performance than H3D-mesh, mesh, and torus networks.

  6. 14 CFR 91.221 - Traffic alert and collision avoidance system equipment and use.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Traffic alert and collision avoidance... RULES Equipment, Instrument, and Certificate Requirements § 91.221 Traffic alert and collision avoidance system equipment and use. (a) All airspace: U.S.-registered civil aircraft. Any traffic alert...

  7. Traffic sign detection and analysis

    DEFF Research Database (Denmark)

    Møgelmose, Andreas; Trivedi, Mohan M.; Moeslund, Thomas B.

    Traffic sign recognition (TSR) is a research field that has seen much activity in the recent decade. This paper introduces the problem and presents 4 recent papers on traffic sign detection and 4 recent papers on traffic sign classification. It attempts to extract recent trends in the field and...

  8. Effects of Traffic Lights on CA Traffic Model

    Institute of Scientific and Technical Information of China (English)

    SuweiFENG; GuoqingGU

    1997-01-01

    Cellular automaton traffic models can include various factors in traffic system with simple regulations and the corresponding computations and simulations are rather convenient and effective.In this paper,the Biham-Middleton-Levine model(briefly saying the BML model)is improved by removing its limitation of synchronized change of traffic lights.In new model,the traffic light at each crossing could arbitrarily change its starting time and tempo of variation and hence the model could more realistically describe the influence of traffic lights on the performance of traffic systems.The cases of traffic light with unsynchronized starting time and different tempo of variation are simulated in this paper.

  9. Traffic flow on realistic road networks with adaptive traffic lights

    CERN Document Server

    de Gier, Jan; Rojas, Omar

    2010-01-01

    We present a model of traffic flow on generic urban road networks based on cellular automata. We apply this model to an existing road network in the Australian city of Melbourne, using empirical data as input. For comparison, we also apply this model to a square-grid network using hypothetical input data. On both networks we compare the effects of non-adative vs adaptive traffic lights, in which instantaneous traffic state information feeds back into the traffic signal schedule. We observe that not only do adaptive traffic lights result in better averages of network observables, they also lead to significantly smaller fluctuations in these observables. We furthermore compare two different systems of adaptive traffic signals, one which is informed by the traffic state on both upstream and downstream links, and one which is informed by upstream links only. We find that, in general, the total travel time is smallest when using the joint upstream-downstream control strategy.

  10. Application of Chaos Theory in the Prediction of Motorised Traffic Flows on Urban Networks

    OpenAIRE

    Aderemi Adewumi; Jimmy Kagamba; Alex Alochukwu

    2016-01-01

    In recent times, urban road networks are faced with severe congestion problems as a result of the accelerating demand for mobility. One of the ways to mitigate the congestion problems on urban traffic road network is by predicting the traffic flow pattern. Accurate prediction of the dynamics of a highly complex system such as traffic flow requires a robust methodology. An approach for predicting Motorised Traffic Flow on Urban Road Networks based on Chaos Theory is presented in this paper. No...

  11. Site Verification of Weigh-in-Motion Traffic and TIRTL Classification Data

    OpenAIRE

    Li, Shuo; Du, Yingzi (Eliza); Jiang, Yi

    2010-01-01

    Quality weigh-in-motion (WIM) traffic data is essential not only in general transportation application, but also in pavement design. The new AASHTO Mechanistic-Empirical Pavement Design Guide (MEPDG) for New and Rehabilitated Pavement Structures requires information on the detailed truck traffic, such as truck traffic volume, truck traffic monthly and hourly variations, vehicle class distribution, axle load, and axle load distributions, instead of the traditional ESALs. In addition, the India...

  12. Review of urban traffic management and the impacts of new vehicle technologies

    OpenAIRE

    Hounsell, N.B.; Shrestha, B. P.; Piao, J.; McDonald, M

    2009-01-01

    Traffic congestion is a growing problem in most urban areas across the world. In recent years, the problem has often been tackled by management of existing capacity rather than the traditional concept of more road building. This requires efficient traffic management tools and has led to widespread implementation of advanced traffic control systems integrated within a wider urban traffic management (UTM) environment. UTM systems collect data from various sources, process and manage the data an...

  13. Policy Refinement for Traffic Management in Home Area Networks: Problem Statement

    OpenAIRE

    Rana, Annie Ibrahim; O Foghlu, Micheal

    2009-01-01

    Traditional home area network (HAN) equipment is usually unmanaged and network traffic is served in best effort fashion. This type of unmanaged network sometimes causes quality-of-service issues in the HAN, for example loss of quality in streamed video or audio content. Traffic management rules using policies to prioritise certain types of traffic according to user requirements and to assign bandwidth limits to other traffic types. However very little work has been done yet addressing the ...

  14. COLOMBO: Exploiting Vehicular Communications at Low Equipment Rates for Traffic Management Purposes

    OpenAIRE

    Krajzewicz, Daniel; Leich, Andreas; Blokpoel, Robbin; Milano, Michela; Stützle, Thomas

    2015-01-01

    While most standardized vehicular communication applications aim on increasing traffic safety, the exchange of messages between vehicles and the environment may be well used for other purposes at no additional cost as well. One possible area of applications is traffic management. Traffic management requires data about the state of the road network. Before being able to predict or control traffic, according data is needed. The COLOMBO project, co-funded by the European Commission, examines the...

  15. EFFICIENT MULTIPATH ROUTING AND WAVELENGTH ALLOCATION USING TRAFFIC GROOMING IN OPTICAL WAVELENGTH DIVISION MULTIPLEXING MESH NETWORKS

    OpenAIRE

    Rajamani, V.; Kavitha, T.

    2012-01-01

    In optical WDM mesh networks, traffic grooming is essential in order to utilize the bandwidth efficiently to minimize the cost and meet the user service requirement. By grooming traffic, it is possible to reduce the total cost of all Add drop multiplexer needed. Also for the high processing capability in a WDM network, the path should be capable of carrying the traffic without any failure. In this study, we use a traffic grooming algorithm to establish light paths between node pairs having th...

  16. Perturbation analysis and sample-path optimization: stochastic flow models of urban traffic networks case

    OpenAIRE

    Sutarto, Herman; Boel, René

    2009-01-01

    Coordination of traffic streams in an urban network, controllable by switching traffic lights, requires a global macroscopic model of the evolution of the flows of vehicle. We propose the use fluid petri nets as modeling tools. For the design of on-line controllers for traffic lights we study the network-wide effects of different local perturbations of the traffic light switching times via fast simulation. The infinitesimal perturbation analysis can under certain conditions lead to optimal cl...

  17. Urban Road Traffic Simulation Techniques

    Directory of Open Access Journals (Sweden)

    Ana Maria Nicoleta Mocofan

    2011-09-01

    Full Text Available For achieving a reliable traffic control system it is necessary to first establish a network parameter evaluation system and also a simulation system for the traffic lights plan. In 40 years of history, the computer aided traffic simulation has developed from a small research group to a large scale technology for traffic systems planning and development. In the following thesis, a presentation of the main modeling and simulation road traffic applications will be provided, along with their utility, as well as the practical application of one of the models in a case study.

  18. Aberrantly Over-Expressed TRPM8 Channels in Pancreatic Adenocarcinoma: Correlation with Tumor Size/Stage and Requirement for Cancer Cells Invasion

    Directory of Open Access Journals (Sweden)

    Nelson S. Yee

    2014-05-01

    Full Text Available The transient receptor potential melastatin-subfamily member 8 (TRPM8 channels control Ca2+ homeostasis. Recent studies indicate that TRPM8 channels are aberrantly expressed and required for cellular proliferation in pancreatic adenocarcinoma. However, the functional significance of TRPM8 in pancreatic tissues is mostly unknown. The objectives of this study are to examine the expression of TRPM8 in various histopathological types of pancreatic tissues, determine its clinical significance in pancreatic adenocarcinoma, and investigate its functional role in cancer cells invasion. We present evidence that, in normal pancreatic tissues, anti-TRPM8 immunoreactivity is detected in the centroacinar cells and the islet endocrine cells. In pre-malignant pancreatic tissues and malignant neoplasms, TRPM8 is aberrantly expressed to variable extents. In the majority of pancreatic adenocarcinoma, TRPM8 is expressed at moderate or high levels, and anti-TRPM8 immunoreactivity positively correlates with the primary tumor size and stage. In the pancreatic adenocarcinoma cell lines that express relatively high levels of TRPM8, short hairpin RNA-mediated interference of TRPM8 expression impaired their ability of invasion. These data suggest that aberrantly expressed TRPM8 channels play contributory roles in pancreatic tumor growth and metastasis, and support exploration of TRPM8 as a biomarker and target of pancreatic adenocarcinoma.

  19. Identification of Amino Acid Residues in Fibroblast Growth Factor 14 (FGF14) Required for Structure-Function Interactions with Voltage-gated Sodium Channel Nav1.6.

    Science.gov (United States)

    Ali, Syed R; Singh, Aditya K; Laezza, Fernanda

    2016-05-20

    The voltage-gated Na(+) (Nav) channel provides the basis for electrical excitability in the brain. This channel is regulated by a number of accessory proteins including fibroblast growth factor 14 (FGF14), a member of the intracellular FGF family. In addition to forming homodimers, FGF14 binds directly to the Nav1.6 channel C-tail, regulating channel gating and expression, properties that are required for intrinsic excitability in neurons. Seeking amino acid residues with unique roles at the protein-protein interaction interface (PPI) of FGF14·Nav1.6, we engineered model-guided mutations of FGF14 and validated their impact on the FGF14·Nav1.6 complex and the FGF14:FGF14 dimer formation using a luciferase assay. Divergence was found in the β-9 sheet of FGF14 where an alanine (Ala) mutation of Val-160 impaired binding to Nav1.6 but had no effect on FGF14:FGF14 dimer formation. Additional analysis revealed also a key role of residues Lys-74/Ile-76 at the N-terminal of FGF14 in the FGF14·Nav1.6 complex and FGF14:FGF14 dimer formation. Using whole-cell patch clamp electrophysiology, we demonstrated that either the FGF14(V160A) or the FGF14(K74A/I76A) mutation was sufficient to abolish the FGF14-dependent regulation of peak transient Na(+) currents and the voltage-dependent activation and steady-state inactivation of Nav1.6; but only V160A with a concomitant alanine mutation at Tyr-158 could impede FGF14-dependent modulation of the channel fast inactivation. Intrinsic fluorescence spectroscopy of purified proteins confirmed a stronger binding reduction of FGF14(V160A) to the Nav1.6 C-tail compared with FGF14(K74A/I76A) Altogether these studies indicate that the β-9 sheet and the N terminus of FGF14 are well positioned targets for drug development of PPI-based allosteric modulators of Nav channels. PMID:26994141

  20. A Network Traffic Control Enhancement Approach over Bluetooth Networks

    DEFF Research Database (Denmark)

    Son, L.T.; Schiøler, Henrik; Madsen, Ole Brun;

    2003-01-01

    This paper analyzes network traffic control issues in Bluetooth data networks as convex optimization problem. We formulate the problem of maximizing of total network flows and minimizing the costs of flows. An adaptive distributed network traffic control scheme is proposed as an approximated...... solution of the stated optimization problem that satisfies quality of service requirements and topologically induced constraints in Bluetooth networks, such as link capacity and node resource limitations. The proposed scheme is decentralized and complies with frequent changes of topology as well...... as capacity limitations and flow requirements in the network. Simulation shows that the performance of Bluetooth networks could be improved by applying the adaptive distributed network traffic control scheme...

  1. The Earliest Ion Channels

    Science.gov (United States)

    Pohorille, A.; Wilson, M. A.; Wei, C.

    2009-12-01

    Supplying protocells with ions required assistance from channels spanning their membrane walls. The earliest channels were most likely short proteins that formed transmembrane helical bundles surrounding a water-filled pore. These simple aggregates were capable of transporting ions with efficiencies comparable to those of complex, contemporary ion channels. Channels with wide pores exhibited little ion selectivity but also imposed only modest constraints on amino acid sequences of channel-forming proteins. Channels with small pores could have been selective but also might have required a more precisely defined sequence of amino acids. In contrast to modern channels, their protocellular ancestors had only limited capabilities to regulate ion flux. It is postulated that subsequent evolution of ion channels progressed primarily to acquire precise regulation, and not high efficiency or selectivity. It is further proposed that channels and the surrounding membranes co-evolved.

  2. Exploiting Witness for Traffic Simulation

    Directory of Open Access Journals (Sweden)

    Azhar Ismail

    2014-03-01

    Full Text Available Traffic congestion in urban cities is an increasing problem. Not only does it lead to an increase in pollution, but the time spent waiting in traffic queues wastes valuable time in addition to causing frustration. A system that can control and manage traffic efficiently is one way that this issue can be reduced. A specific road traffic intersection in South Manchester, UK, was selected for investigation as it experiences high levels of traffic flow through it during the evening peak time. This has led to large queues and long waiting times due to the fixed timings of the traffic lights. This paper explores strategies to better control the traffic flow through it. A model of the selected traffic junction has been built using Witness simulation software. Data for this junction has been obtained partially from observations and mostly from traffic surveys enabling a simulation of the traffic flow. Analysing the results allowed two alternative scenarios to be developed and simulated. Results from one of the scenarios showed noticeable reductions in the average queue waiting times at the traffic junction.

  3. Web traffic and firm performance

    DEFF Research Database (Denmark)

    Farooq, Omar; Aguenaou, Samir

    2013-01-01

    Does the traffic generated by websites of firms signal anything to stock market participants? Does higher web-traffic translate into availability of more information and therefore lower agency problems? And if answers to above questions are in affirmative, does higher web-traffic traffic translate...... into better firm performance? This paper aims to answer these questions by documenting a positive relationship between the extent of web-traffic and firm performance in the MENA region during the 2010. We argue that higher web-traffic lowers the agency problems in firms by disseminating more information...... to stock market participants. Consequently, lower agency problems translate into better performance. Furthermore, we also show that agency reducing role of web-traffic is more pronounced in regimes where information environment is already bad. For example, our results show stronger impact of web...

  4. Inaccuracy in traffic forecasts

    DEFF Research Database (Denmark)

    Flyvbjerg, Bent; Holm, Mette K. Skamris; Buhl, Søren Ladegaard

    2006-01-01

    This paper presents results from the first statistically significant study of traffic forecasts in transportation infrastructure projects. The sample used is the largest of its kind, covering 210 projects in 14 nations worth US$58 billion. The study shows with very high statistical significance...... that forecasters generally do a poor job of estimating the demand for transportation infrastructure projects. The result is substantial downside financial and economic risk. Forecasts have not become more accurate over the 30-year period studied. If techniques and skills for arriving at accurate demand...... reference class forecasting. Highly inaccurate traffic forecasts combined with large standard deviations translate into large financial and economic risks. But such risks are typically ignored or downplayed by planners and decision-makers, to the detriment of social and economic welfare. The paper presents...

  5. Real-Time Communication Support for Cooperative, Infrastructure-Based Traffic Safety Applications

    Directory of Open Access Journals (Sweden)

    Annette Böhm

    2011-01-01

    Full Text Available The implementation of ITS (Intelligent Transport Systems services offers great potential to improve the level of safety, efficiency and comfort on our roads. Although cooperative traffic safety applications rely heavily on the support for real-time communication, the Medium Access Control (MAC mechanism proposed for the upcoming IEEE 802.11p standard, intended for ITS applications, does not offer deterministic real-time support, that is, the access delay to the common radio channel is not upper bounded. To address this problem, we present a framework for a vehicle-to-infrastructure-based (V2I communication solution extending IEEE 802.11p by introducing a collision-free MAC phase assigning each vehicle an individual priority based on its geographical position, its proximity to potential hazards and the overall road traffic density. Our solution is able to guarantee the timely treatment of safety-critical data, while minimizing the required length of this real-time MAC phase and freeing bandwidth for best-effort services (targeting improved driving comfort and traffic efficiency. Furthermore, we target fast connection setup, associating a passing vehicle to an RSU (Road Side Unit, and proactive handover between widely spaced RSUs. Our real-time MAC concept is evaluated analytically and by simulation based on a realistic task set from a V2I highway merge assistance scenario.

  6. Integrating Traffic Signal Performance Measures into Agency Business Processes

    OpenAIRE

    Day, Christopher M.; Bullock, Darcy M; Li, Howell; Lavrenz, Steven M; Smith, W. Benjamin; Sturdevant, James R

    2016-01-01

    This report discusses uses of and requirements for performance measures in traffic signal systems facilitated by high-resolution controller event data. Uses of external travel time measurements are also discussed. The discussion is led by a high-level synthesis of the systems engineering concepts for traffic signal control, considering technical and non-technical aspects of the problem. This is followed by a presentation of the requirements for implementing data collection and processing of t...

  7. Integrated Modeling of Air Traffic, Aviation Weather, and Communication Systems

    OpenAIRE

    Quan, Chuanwen

    2007-01-01

    Aviation suffers many delays due to the lack of timely air traffic flow management. These delays are also caused by the uncertainty weather information; and the lack of efficient dissemination of weather products to pilots. It is clear that better models are needed to quantify air traffic flow in three flight regions - en-route, in the terminal, and on the ground, to determine aviation weather information requirements at each region, and to quantify their bandwidth requirements. Furthermore,...

  8. Physics of Traffic Flow

    Science.gov (United States)

    Davis, L. C.

    2015-03-01

    The Texas A&M Transportation Institute estimated that traffic congestion cost the United States 121 billion in 2011 (the latest data available). The cost is due to wasted time and fuel. In addition to accidents and road construction, factors contributing to congestion include large demand, instability of high-density free flow and selfish behavior of drivers, which produces self-organized traffic bottlenecks. Extensive data collected on instrumented highways in various countries have led to a better understanding of traffic dynamics. From these measurements, Boris Kerner and colleagues developed a new theory called three-phase theory. They identified three major phases of flow observed in the data: free flow, synchronous flow and wide moving jams. The intermediate phase is called synchronous because vehicles in different lanes tend to have similar velocities. This congested phase, characterized by lower velocities yet modestly high throughput, frequently occurs near on-ramps and lane reductions. At present there are only two widely used methods of congestion mitigation: ramp metering and the display of current travel-time information to drivers. To find more effective methods to reduce congestion, researchers perform large-scale simulations using models based on the new theories. An algorithm has been proposed to realize Wardrop equilibria with real-time route information. Such equilibria have equal travel time on alternative routes between a given origin and destination. An active area of current research is the dynamics of connected vehicles, which communicate wirelessly with other vehicles and the surrounding infrastructure. These systems show great promise for improving traffic flow and safety.

  9. Organic traffic control

    OpenAIRE

    Prothmann, Holger

    2011-01-01

    Modern cities cannot be imagined without traffic lights controlling the road network. To handle the network's changing demands efficiently, the signal plan specification needs to be shifted from the design time to the run-time of a signal system. The generic observer/controller architecture proposed for Organic Computing facilitates this shift. A two-levelled learning mechanism optimises signal plans on-line while a distributed coordination mechanism establishes green waves in the road network.

  10. Untieing the Traffic Knot

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Beijing is working to resolve its longtime transportation problems before the 2008 Olympics One traffic jam after another, annoying horns, endless lines of cars,impatient sighs from passengers on an overcrowded bus, the youstomped-on-my-toe quarreling in the subway train, all have led to the unsurprising result that Beijing scored at the tail end of a survey of 287 cities in the category of transport satisfaction in China’s 2006 Report on the Quality of Urban Life.

  11. Assessing road traffic expression

    OpenAIRE

    Fábio Silva; Cesar Analide; Paulo Novais

    2014-01-01

    Road traffic is a problem which is increasing in cities with large population. Unrelated to this fact the number of portable and wearable devices has also been increasing throughout the population of most countries. With this advent, the capacity to monitor and register data about people habits and locations as well as more complex data such as intensity and strength of movements has created an opportunity to contribute to the general wealth and comfort within these environments. Ambient Inte...

  12. MERGING AND SPLITTING SECOND-ORDER SELF-SIMILAR PROCESSES (TRAFFICS)

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Recent traffic measurements in corporate LANs, Variable-Bit-Rate (VBR) video sources, ISDN control channels, and other communication systems, have indicated traffic behavior of self-similar nature, which has implications for design, control and analysis of high-speed networks. Merging and splitting are two basic networking operations. This paper gave the necessary and sufficient conditions for that merging of second-order self-similar traffic streams also results in a second-order self-similar stream. It shows that splitting traffic streams of the second-order self-similar stream are still self-similar streams by the independent splitting operation.

  13. The Physics of Traffic

    Science.gov (United States)

    Davis, L. Craig

    2006-03-01

    Congestion in freeway traffic is an example of self-organization in the language of complexity theory. Nonequilibrium, first-order phase transitions from free flow cause complex spatiotemporal patterns. Two distinct phases of congestion are observed in empirical traffic data--wide moving jams and synchronous flow. Wide moving jams are characterized by stopped or slowly moving vehicles within the jammed region, which widens and moves upstream at 15-20 km/h. Above a critical density of vehicles, a sudden decrease in the velocity of a lead vehicle can initiate a transition from metastable states to this phase. Human behaviors, especially delayed reactions, are implicated in the formation of jams. The synchronous flow phase results from a bottleneck such as an on-ramp. Thus, in contrast to a jam, the downstream front is pinned at a fixed location. The name of the phase comes from the equilibration (or synchronization) of speed and flow rate across all lanes caused by frequent vehicle lane changes. Synchronous flow occurs when the mainline flow and the rate of merging from an on-ramp are sufficiently large. Large-scale simulations using car-following models reproduce the physical phenomena occurring in traffic and suggest methods to improve flow and mediate congestion.

  14. Effects of traffic noise

    Energy Technology Data Exchange (ETDEWEB)

    Gottlob, D.

    1986-02-01

    One of the main sources of noise is road traffic. In 1984 there were over 25 million cars, 1.2 million lorries, 1.3 million motor cycles and 1.6 million mopeds using our roads. Opinion polls showed that 21% of the population felt that they were affected by traffic noise as a nuisance factor. An outline of the effects of this noise on the affected population is given, illustrated by diagrams. Details about noise emissions (drive-past level) of the different types of vehicles in city traffic are stated and the effects of noise described. The author goes into the nuisance effect (noise is not a physical factor, but a psychosocial one), changes in behaviour (ways of speaking, reduction of stress on households in proportion to rising income and higher educational levels) and the consequences for health (the reaction of the body to noise is primarily a consequence of the psychosomatic organisation of ow bodies). In conclusion, the author deals with the subjective efficiency of noise protection measures. (HWJ).

  15. Assessing Road Traffic Expression

    Directory of Open Access Journals (Sweden)

    Fábio Silva

    2014-12-01

    Full Text Available Road traffic is a problem which is increasing in cities with large population. Unrelated to this fact the number of portable and wearable devices has also been increasing throughout the population of most countries. With this advent, the capacity to monitor and register data about people habits and locations as well as more complex data such as intensity and strength of movements has created an opportunity to contribute to the general wealth and comfort within these environments. Ambient Intelligence and Intelligent Decision Making processes can benefit from the knowledge gathered by these devices to improve decisions on everyday tasks such as deciding navigation routes by car, bicycle or other means of transportation and avoiding route perils. The concept of computational sustainability may also be applied to this problem. Current applications in this area demonstrate the usefulness of real time system that inform the user of certain conditions in the surrounding area. On the other hand, the approach presented in this work aims to describe models and approaches to automatically identify current states of traffic inside cities and use methods from computer science to improve overall comfort and the sustainability of road traffic both with the user and the environment in mind. Such objective is delivered by analyzing real time contributions from those mobile ubiquitous devices to identifying problematic situations and areas under a defined criteria that have significant influence towards a sustainable use of the road transport infrastructure.

  16. Intelligent Video Traffic Smooth Mechanism for Multimedia Communication

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A principal challenge in supporting real-time video services over ATM is the need to provide synchronous play-out in the face of stochastic end-to-end network delays. In this paper, an intelligent traffic smooth mechanism ( ITSM ) is proposed to meet the continuity requirement which is composed of a back-propagation neural network ( BPNN ) traffic predictor, a play-out buffer, and a fuzzy neural network ( FNN ) based play-out rate determinator. The BPNN traffic predictor online predicts the mean packet rate of the traffic in the future interval ( FI ) and the FNN is designed to adaptively determinate the play-out time according to the number of packets in the buffer and the traffic character predicted. Simulation results show that compared to the window mechanism, ITSM achieves high continuity with accepted delay. Furthermore, ITSM can be adaptively modified to meet the QoS of different kinds of services by FNN parameter training.

  17. Trace Analysis of Driver Behavior on Traffic Violator by Using Big Data (Traffic Program) in Korea

    OpenAIRE

    Lee, Jonghak

    2016-01-01

    This study aims to prove the effectiveness of traffic safety education program for traffic violators. Traffic violators who finished the traffic safety education programs were tracked down. In order to analyze the effectiveness of traffic safety education program, traffic violator’s data during ten-year period were used. This study analyzed how traffic violators changed their attitudes about traffic law abidance. Also predicted social benefits from traffic safety education program...

  18. Throughput Enhancement Using Adaptive Delay Barrier Function over HSDPA System in Mixed Traffic Scenarios

    Science.gov (United States)

    Kim, Yong-Seok

    In this paper, we consider a method to enhance the throughput of HSDPA systems in the mixed traffic scenario. A channel-dependent adaptive delay barrier (DB) function is proposed to maximize throughput of best-effort (BE) traffic while satisfying the delay latency of voice over internet protocol (VoIP) service. Simulations show that the proposed channel-adaptive DB function raises the throughput of BE traffic service by 30% compared to the conventional scheme, without degrading the capacity of VoIP service over HSDPA system.

  19. Towards space traffic management system

    Science.gov (United States)

    Cukurtepe, Haydar; Akgun, Ilker

    2009-09-01

    Space is getting more and more crowded because of the increasing number of space objects and the limited availability of prime orbital locations. The continual situation makes space operations more and more complicated by the time passes. This complexity requires more international coordination and data to be considered. The paper makes the case for a space traffic management system (STMS) and proposes a reference model for STMS. The proposed STMS performs five main services: Space Monitoring & Tracking Service, Space Data Management Service, Space Operation Service, Space Warning Service and Space Conflict Management Service. The paper elaborates and explains these services, taking into consideration the political and especially technical challenges together with pertinent international law, regulations and accepted practice.

  20. Maximizing multicast call acceptance rate in multi-channel multi-interface wireless mesh networks

    OpenAIRE

    Yeung, KL; Chiu, HS

    2010-01-01

    In this paper, we consider the problem of constructing bandwidth-guaranteed multicast tree in multi-channel multi-interface wireless mesh networks. We focus on the scenario of dynamic multicast call arrival, where each call has a specific bandwidth requirement. A call is accepted if a multicast tree with sufficient bandwidth on each link can be constructed. Intuitively, if the carried load on both the most-heavily loaded channel and the most-heavily loaded node is minimized, the traffic load ...

  1. Traffic Control by Traffic Wardens in Minna, Niger State, Nigeria

    Directory of Open Access Journals (Sweden)

    P. N. NDOKE

    2006-01-01

    Full Text Available Traffic control by traffic wardens on three at-grade interactions in Minna, Northern Nigeria has been analysed. During the morning peak periods, it was observed that with traffic warden control, none of the approaches of the intersections operated beyond level of service E. However, when the wardens did not control traffic, the approaches operated at level of service, F, which has been shown in studies to be unacceptable to most drivers. Taking other factors like stability of electricity supply, motorists’ behaviour and society’s acceptance of innovations into consideration, it has been concluded that for now, there is no alternative to the traffic warden in traffic control in developing cities.

  2. Distributed Trajectory Flexibility Preservation for Traffic Complexity Mitigation

    Science.gov (United States)

    Idris, Husni; Wing, David; Delahaye, Daniel

    2009-01-01

    The growing demand for air travel is increasing the need for mitigation of air traffic congestion and complexity problems, which are already at high levels. At the same time new information and automation technologies are enabling the distribution of tasks and decisions from the service providers to the users of the air traffic system, with potential capacity and cost benefits. This distribution of tasks and decisions raises the concern that independent user actions will decrease the predictability and increase the complexity of the traffic system, hence inhibiting and possibly reversing any potential benefits. In answer to this concern, the authors propose the introduction of decision-making metrics for preserving user trajectory flexibility. The hypothesis is that such metrics will make user actions naturally mitigate traffic complexity. In this paper, the impact of using these metrics on traffic complexity is investigated. The scenarios analyzed include aircraft in en route airspace with each aircraft meeting a required time of arrival in a one-hour time horizon while mitigating the risk of loss of separation with the other aircraft, thus preserving its trajectory flexibility. The experiments showed promising results in that the individual trajectory flexibility preservation induced self-separation and self-organization effects in the overall traffic situation. The effects were quantified using traffic complexity metrics based on Lyapunov exponents and traffic proximity.

  3. Accurate Multisteps Traffic Flow Prediction Based on SVM

    Directory of Open Access Journals (Sweden)

    Zhang Mingheng

    2013-01-01

    Full Text Available Accurate traffic flow prediction is prerequisite and important for realizing intelligent traffic control and guidance, and it is also the objective requirement for intelligent traffic management. Due to the strong nonlinear, stochastic, time-varying characteristics of urban transport system, artificial intelligence methods such as support vector machine (SVM are now receiving more and more attentions in this research field. Compared with the traditional single-step prediction method, the multisteps prediction has the ability that can predict the traffic state trends over a certain period in the future. From the perspective of dynamic decision, it is far important than the current traffic condition obtained. Thus, in this paper, an accurate multi-steps traffic flow prediction model based on SVM was proposed. In which, the input vectors were comprised of actual traffic volume and four different types of input vectors were compared to verify their prediction performance with each other. Finally, the model was verified with actual data in the empirical analysis phase and the test results showed that the proposed SVM model had a good ability for traffic flow prediction and the SVM-HPT model outperformed the other three models for prediction.

  4. CATS-based Air Traffic Controller Agents

    Science.gov (United States)

    Callantine, Todd J.

    2002-01-01

    This report describes intelligent agents that function as air traffic controllers. Each agent controls traffic in a single sector in real time; agents controlling traffic in adjoining sectors can coordinate to manage an arrival flow across a given meter fix. The purpose of this research is threefold. First, it seeks to study the design of agents for controlling complex systems. In particular, it investigates agent planning and reactive control functionality in a dynamic environment in which a variety perceptual and decision making skills play a central role. It examines how heuristic rules can be applied to model planning and decision making skills, rather than attempting to apply optimization methods. Thus, the research attempts to develop intelligent agents that provide an approximation of human air traffic controller behavior that, while not based on an explicit cognitive model, does produce task performance consistent with the way human air traffic controllers operate. Second, this research sought to extend previous research on using the Crew Activity Tracking System (CATS) as the basis for intelligent agents. The agents use a high-level model of air traffic controller activities to structure the control task. To execute an activity in the CATS model, according to the current task context, the agents reference a 'skill library' and 'control rules' that in turn execute the pattern recognition, planning, and decision-making required to perform the activity. Applying the skills enables the agents to modify their representation of the current control situation (i.e., the 'flick' or 'picture'). The updated representation supports the next activity in a cycle of action that, taken as a whole, simulates air traffic controller behavior. A third, practical motivation for this research is to use intelligent agents to support evaluation of new air traffic control (ATC) methods to support new Air Traffic Management (ATM) concepts. Current approaches that use large, human

  5. Robust and reactive traffic engineering for dynamic traffic demands

    OpenAIRE

    Casas Hernandez, Pedro; Fillatre, Lionel; Vaton, Sandrine

    2008-01-01

    Traffic engineering (TE) has become a challenging mechanism for network management and resources optimization due to uncertain and difficult to predict traffic patterns. Recent works have proposed robust optimization techniques to cope with uncertain traffic, computing a stable routing configuration that is immune to demand variations within certain uncertainty set. However, using a single routing configuration for longtime periods can be highly inefficient. Even more, the presence of abnorma...

  6. Dividing the Traffic Matrix to Approach Optimal Traffic Engineering

    OpenAIRE

    Balon, Simon; Leduc, Guy

    2006-01-01

    In this paper we propose a new method to approach optimal Traffic Engineering routing. The method consists of dividing the traffic matrix into $N$ sub-matrices, called strata, and route each of these independently. We propose two different implementations of our method in routers. Our method can also be used to compute a very precise approximation of the optimal value of a given objective function for comparison to heuristic Traffic Engineering algorithms. For this application, our algorithm ...

  7. Traffic Data and Their Implications for Consistent Traffic Flow Modeling

    OpenAIRE

    Helbing, Dirk

    1998-01-01

    The paper analyzes traffic data of the Dutch freeway A9 with respect to certain aspects which are relevant for traffic flow modeling as well as the calibration of model parameters and functions. Apart from the dynamic velocity distribution, the density-dependence and the temporal evolution of various, partly lane-specific quantities is investigated. The results are well compatible with recent macroscopic traffic flow models which have been derived from the dynamics of driver-vehicle units. Th...

  8. Evaluation of Traffic Management Measures on Road Traffic Noise

    OpenAIRE

    Bhaskar, A.; Chung, E; Dumont, A.-G.

    2006-01-01

    Road traffic noise affects the quality of life in the areas adjoining the road. The effect of traffic noise on people is wide ranging and may include sleep disturbance and negative impact on work efficiency. To address the problem of traffic noise, it is necessary to estimate the noise level. For this, a number of noise estimation models have been developed which can estimate noise at the receptor points, based on simple configuration of buildings. Howe...

  9. Optimal traffic states in a cellular automaton for city traffic

    OpenAIRE

    Barlovic, Robert; Brockfeld, Elmar; Schreckenberg, Michael; Schadschneider, Andreas

    2003-01-01

    The impact of global traffic light control strategies for city networks is analyzed in a recently proposed cellular automaton model. The model combines basic ideas of the Biham-Middleton-Levine model for city traffic and the Nage-Schreckenberg model for highway traffic. The city network has a simple square lattice geometry. All streets and intersections are treated equally, i.e., there are no dominant streets.

  10. Lagrangian Multi-Class Traffic State Estimation

    OpenAIRE

    Y. Yuan

    2013-01-01

    Road traffic is important to everybody in the world. People travel and commute everyday. For those who travel by cars (or other types of road vehicles), traffic congestion is a daily experience. One essential goal of traffic researchers is to reduce traffic congestion and to improve the whole traffic system operation and the environment. To achieve this goal, we have to first understand prevailing traffic situations, then perform pro-active traffic control and management. The estimation of tr...

  11. IDMA-Based MAC Protocol for Satellite Networks with Consideration on Channel Quality

    Directory of Open Access Journals (Sweden)

    Gongliang Liu

    2014-01-01

    Full Text Available In order to overcome the shortcomings of existing medium access control (MAC protocols based on TDMA or CDMA in satellite networks, interleave division multiple access (IDMA technique is introduced into satellite communication networks. Therefore, a novel wide-band IDMA MAC protocol based on channel quality is proposed in this paper, consisting of a dynamic power allocation algorithm, a rate adaptation algorithm, and a call admission control (CAC scheme. Firstly, the power allocation algorithm combining the technique of IDMA SINR-evolution and channel quality prediction is developed to guarantee high power efficiency even in terrible channel conditions. Secondly, the effective rate adaptation algorithm, based on accurate channel information per timeslot and by the means of rate degradation, can be realized. What is more, based on channel quality prediction, the CAC scheme, combining the new power allocation algorithm, rate scheduling, and buffering strategies together, is proposed for the emerging IDMA systems, which can support a variety of traffic types, and offering quality of service (QoS requirements corresponding to different priority levels. Simulation results show that the new wide-band IDMA MAC protocol can make accurate estimation of available resource considering the effect of multiuser detection (MUD and QoS requirements of multimedia traffic, leading to low outage probability as well as high overall system throughput.

  12. Interdomain traffic engineering with BGP

    OpenAIRE

    Quoitin, Bruno; Uhlig, Steve; Pelsser, Cristel; Swinnen, Louis; Bonaventure, Olivier

    2003-01-01

    Traffic engineering is performed by means of a set of techniques that can be used to better control the flow of packets inside an IP network We discuss the utilization of these techniques across interdomain boundaries in the global Internet. We first analyze the characteristics of interdomain traffic on the basis of measurements from three different Internet service providers and show that a small number of sources are responsible for a large fraction of the traffic. Across interdomain bounda...

  13. MPC in Urban Traffic Management

    OpenAIRE

    Tettamanti, Tamás; Varga, Istvan; Peni, Tamas

    2010-01-01

    This chapter introduced the aspects of MPC applied in urban traffic management. As the urban traffic is a complex system having special attributes the appropriate traffic model had to be discussed in details as well. At the same time MPC technology is suitable to control such complex system optimally and real-time. The main control aim was the optimal and coordinated control which can be satisfied. The applicability was demonstrated by several simulations. Furthermore a distributed technology...

  14. Traffic noise and cardiovascular disease

    OpenAIRE

    Selander, Jenny

    2010-01-01

    Traffic noise is an increasing problem in urban areas worldwide, but health effects in relation to traffic noise exposure are not well understood. Several studies show that noise may give rise to acute stress reactions, possibly leading to cardiovascular effects, but the evidence is limited on cardiovascular risks associated with traffic noise exposure. Cardiovascular effects have been indicated for other environmental stressors such as occupational noise exposure and job ...

  15. Research on Prediction of Traffic Congestion State

    Directory of Open Access Journals (Sweden)

    Zhao Jun

    2015-01-01

    Full Text Available This method of prediction using the data mining to analyze huge amounts of data as a preferred tool has been widely used in various fields. In the midst of it, the routine traffic data exists in a large number of isolated data in real time without establishing relationships with other data, and detects the amount of data which is greater than that at present. The usage of these data which is relatively shallow requires an in-depth analysis of its data model. Therefore, this paper uses a fuzzy clustering analysis method of feature points to study the traffic flow, uses a Markov decision chain model to study traffic jams, uses quantitative sample points based on the information entropy to calculate traffic flow trends and uses a heuristic prediction model to predict the road con-gestion. Through the simulation experiment which verifies the correctness of the model, this research is to advance the development of the road and to provide a basis for a dredging plan.

  16. Matlab Traffic Toolbox

    Czech Academy of Sciences Publication Activity Database

    Dohnal, Pavel

    Bratislava : Slovak University of technology, 2007 - (Mikleš, J.; Fikar, M.; Kvasnica, M.), s. 1-6 ISBN 978-80-227-2677-1. [16th International Conference on Process Control. Štrbské pleso - Vysoké Tatry (SK), 11.06.2007-14.06.2007] R&D Projects: GA MŠk 1M0572; GA AV ČR 1ET100750401; GA ČR(CZ) GA102/05/0271 Institutional research plan: CEZ:AV0Z10750506 Keywords : Matlab * Traffic * Toolbox * Aimsun Subject RIV: BC - Control Systems Theory

  17. Matlab Traffic Toolbox

    Czech Academy of Sciences Publication Activity Database

    Dohnal, Pavel

    Bratislava : Slovak University of technology, 2007 - (Mikleš, J.; Fikar, M.; Kvasnica, M.) ISBN 978-80-227-2677-1. [16th International Conference on Process Control. 11.06.2007-14.06.2007, Štrbské pleso - Vysoké Tatry] R&D Projects: GA MŠk 1M0572; GA AV ČR 1ET100750401; GA ČR(CZ) GA102/05/0271 Institutional research plan: CEZ:AV0Z10750506 Keywords : Matlab * Toolbox * Aimsun * Traffic Subject RIV: BC - Control Systems Theory

  18. Differential effects of traffic sign stimuli upon speeding in school zones following a traffic light interruption.

    Science.gov (United States)

    Gregory, Bree; Irwin, Julia D; Faulks, Ian J; Chekaluk, Eugene

    2016-01-01

    Motorists whose journey has been interrupted by signalized traffic intersections in school zones resume their journey at a faster vehicle speed than motorists who have not been required to stop. Introducing a flashing "check speed" sign 70m after the traffic intersections counteracts this interruptive effect. The present study examined which aspects of a reminder sign are responsible for reducing the speeding behavior of interrupted motorists. When a sign that combines both written text and flashing lights was introduced, interrupted motorists did not speed, traveling on average 0.82km/h below the 40km/h speed limit when measured 100m from traffic intersections. Alternatively, when only the flashing lights were visible the interrupted motorists sped 3.36km/h over the 40km/h speed limit. Similar vehicular speeds were observed when only the written text was visible and when no sign was present (7.67 and 7.49km/h over the 40km/h speed limit, respectively). This indicates that static reminder signs add little value over the absence of a school zone reminder sign; the presence of both cues is necessary to fully offset the interruptive effect. This study also highlights the benefit of using exogenous visual cues in traffic signs to capture drivers' attention. These findings have practical implications for the design and use of traffic signs to increase compliance with posted speed limits. PMID:26545011

  19. FPGA Based Real-time Network Traffic Analysis using Traffic Dispersion Patterns

    Energy Technology Data Exchange (ETDEWEB)

    Khan, F; Gokhale, M; Chuah, C N

    2010-03-26

    The problem of Network Traffic Classification (NTC) has attracted significant amount of interest in the research community, offering a wide range of solutions at various levels. The core challenge is in addressing high amounts of traffic diversity found in today's networks. The problem becomes more challenging if a quick detection is required as in the case of identifying malicious network behavior or new applications like peer-to-peer traffic that have potential to quickly throttle the network bandwidth or cause significant damage. Recently, Traffic Dispersion Graphs (TDGs) have been introduced as a viable candidate for NTC. The TDGs work by forming a network wide communication graphs that embed characteristic patterns of underlying network applications. However, these patterns need to be quickly evaluated for mounting real-time response against them. This paper addresses these concerns and presents a novel solution for real-time analysis of Traffic Dispersion Metrics (TDMs) in the TDGs. We evaluate the dispersion metrics of interest and present a dedicated solution on an FPGA for their analysis. We also present analytical measures and empirically evaluate operating effectiveness of our design. The mapped design on Virtex-5 device can process 7.4 million packets/second for a TDG comprising of 10k flows at very high accuracies of over 96%.

  20. A shared data environment for the Military Traffic Management Command Directorate of International Traffic

    Energy Technology Data Exchange (ETDEWEB)

    Russell, D.L.; Wheeler, V.V. [Tennessee Univ., Knoxville, TN (United States); Truett, L.F. [Oak Ridge National Lab., TN (United States)

    1992-01-01

    In September 1991, Oak Ridge National Laboratory (ORNL) completed tasking to assist the Military Traffic Management Command Directorate of International Traffic (MTIT) in the analysis of a potential Shared Data Environment (SDE) for MTIT automated cargo traffic systems. This analysis was a preliminary effort with emphasis on documentation of requirements, examination of design alternatives, and identification of specific MTIT systems` data sharing problems. This report records the results of the ORNL analysis. The SDE envisioned by ORNL at this point in the analysis is not merely a repository of information; it is also a system that allows processing of distributed data. To provide high-level access to and control over international cargo processes, ORNL recommends a loosely coupled, replicated database design with high-speed communications among all sites.

  1. A shared data environment for the Military Traffic Management Command Directorate of International Traffic

    Energy Technology Data Exchange (ETDEWEB)

    Russell, D.L.; Wheeler, V.V. (Tennessee Univ., Knoxville, TN (United States)); Truett, L.F. (Oak Ridge National Lab., TN (United States))

    1992-01-01

    In September 1991, Oak Ridge National Laboratory (ORNL) completed tasking to assist the Military Traffic Management Command Directorate of International Traffic (MTIT) in the analysis of a potential Shared Data Environment (SDE) for MTIT automated cargo traffic systems. This analysis was a preliminary effort with emphasis on documentation of requirements, examination of design alternatives, and identification of specific MTIT systems' data sharing problems. This report records the results of the ORNL analysis. The SDE envisioned by ORNL at this point in the analysis is not merely a repository of information; it is also a system that allows processing of distributed data. To provide high-level access to and control over international cargo processes, ORNL recommends a loosely coupled, replicated database design with high-speed communications among all sites.

  2. Trace Analysis of Driver Behavior on Traffic Violator by Using Big Data (Traffic Program in Korea

    Directory of Open Access Journals (Sweden)

    Lee, Jonghak

    2016-01-01

    Full Text Available This study aims to prove the effectiveness of traffic safety education program for traffic violators. Traffic violators who finished the traffic safety education programs were tracked down. In order to analyze the effectiveness of traffic safety education program, traffic violator’s data during ten-year period were used. This study analyzed how traffic violators changed their attitudes about traffic law abidance. Also predicted social benefits from traffic safety education program for traffic violators. Effectiveness of traffic accident prevention through traffic safety education program is approximately 93%. In terms of social benefits, it shows more than $12 billion Even though the effectiveness of traffic safety education program represents remarkable results, but this program is made for traffic violators who have already committed traffic offenses in the past. So in order to prevent traffic violations in advance, specific education program for potentially risky drivers is necessary.

  3. Handling Deafness Problem of Scheduled Multi-Channel Polling MACs

    Science.gov (United States)

    Jiang, Fulong; Liu, Hao; Shi, Longxing

    Combining scheduled channel polling with channel diversity is a promising way for a MAC protocol to achieve high energy efficiency and performance under both light and heavy traffic conditions. However, the deafness problem may cancel out the benefit of channel diversity. In this paper, we first investigate the deafness problem of scheduled multi-channel polling MACs with experiments. Then we propose and evaluate two schemes to handle the deafness problem. Our experiment shows that deafness is a significant reason for performance degradation in scheduled multi-channel polling MACs. A proper scheme should be chosen depending on the traffic pattern and the design objective.

  4. Intracellular membrane traffic at high resolution

    OpenAIRE

    van Weering, Jan R.T.; Brown, Edward; Sharp, Thomas H.; Mantell, Judith; Cullen, Peter J.; Verkade, Paul

    2010-01-01

    Membrane traffic between organelles is essential for a multitude of processes that maintain cell homeostasis. Many steps in these tightly regulated trafficking pathways take place in microdomains on the membranes of organelles, which require analysis at nanometer resolution. Electron Microscopy (EM) can visualize these processes in detail and is mainly responsible for our current view of morphology on the subcellular level. This review discusses how EM can be applied to solve many questions o...

  5. Measuring the Complexity of Self-organizing Traffic Lights

    CERN Document Server

    Zubillaga, Dario; Aguilar, Luis Daniel; Zapotecatl, Jorge; Fernandez, Nelson; Aguilar, Jose; Rosenblueth, David A; Gershenson, Carlos

    2014-01-01

    We apply measures of complexity, emergence and self-organization to an abstract city traffic model for comparing a traditional traffic coordination method with a self-organizing method in two scenarios: cyclic boundaries and non-orientable boundaries. We show that the measures are useful to identify and characterize different dynamical phases. It becomes clear that different operation regimes are required for different traffic demands. Thus, not only traffic is a non-stationary problem, which requires controllers to adapt constantly. Controllers must also change drastically the complexity of their behavior depending on the demand. Based on our measures, we can say that the self-organizing method achieves an adaptability level comparable to a living system.

  6. Measuring the Complexity of Self-Organizing Traffic Lights

    Directory of Open Access Journals (Sweden)

    Darío Zubillaga

    2014-04-01

    Full Text Available We apply measures of complexity, emergence, and self-organization to an urban traffic model for comparing a traditional traffic-light coordination method with a self-organizing method in two scenarios: cyclic boundaries and non-orientable boundaries. We show that the measures are useful to identify and characterize different dynamical phases. It becomes clear that different operation regimes are required for different traffic demands. Thus, not only is traffic a non-stationary problem, requiring controllers to adapt constantly; controllers must also change drastically the complexity of their behavior depending on the demand. Based on our measures and extending Ashby’s law of requisite variety, we can say that the self-organizing method achieves an adaptability level comparable to that of a living system.

  7. Large scale traffic simulations

    Energy Technology Data Exchange (ETDEWEB)

    Nagel, K.; Barrett, C.L. [Los Alamos National Lab., NM (United States)]|[Santa Fe Institute, NM (United States); Rickert, M. [Los Alamos National Lab., NM (United States)]|[Universitaet zu Koeln (Germany)

    1997-04-01

    Large scale microscopic (i.e. vehicle-based) traffic simulations pose high demands on computational speed in at least two application areas: (i) real-time traffic forecasting, and (ii) long-term planning applications (where repeated {open_quotes}looping{close_quotes} between the microsimulation and the simulated planning of individual person`s behavior is necessary). As a rough number, a real-time simulation of an area such as Los Angeles (ca. 1 million travellers) will need a computational speed of much higher than 1 million {open_quotes}particle{close_quotes} (= vehicle) updates per second. This paper reviews how this problem is approached in different projects and how these approaches are dependent both on the specific questions and on the prospective user community. The approaches reach from highly parallel and vectorizable, single-bit implementations on parallel supercomputers for Statistical Physics questions, via more realistic implementations on coupled workstations, to more complicated driving dynamics implemented again on parallel supercomputers. 45 refs., 9 figs., 1 tab.

  8. Fastlane: Traffic flow modeling and multi-class dynamic traffic management

    OpenAIRE

    Schreiter, T.; Van Wageningen-Kessels, F.L.M.; Yuan, Y; Lint, van J. W. C.; Hoogendoorn, S.P.

    2012-01-01

    Dynamic Traffic Management (DTM) aims to improve traffic conditions. DTM usually consists of two steps: first the current traffic is estimated, then appropriate control actions are determined based on that estimate. In order to estimate and control the traffic, a suitable traffic flow model that reproduces the properties of traffic well must be used. One of the most important properties is that traffic is composed of multiple vehicle classes. While many traffic flow models have been proposed ...

  9. An ultra low-power and traffic-adaptive medium access control protocol for wireless body area network.

    Science.gov (United States)

    Ullah, Sana; Kwak, Kyung Sup

    2012-06-01

    Wireless Body Area Network (WBAN) consists of low-power, miniaturized, and autonomous wireless sensor nodes that enable physicians to remotely monitor vital signs of patients and provide real-time feedback with medical diagnosis and consultations. It is the most reliable and cheaper way to take care of patients suffering from chronic diseases such as asthma, diabetes and cardiovascular diseases. Some of the most important attributes of WBAN is low-power consumption and delay. This can be achieved by introducing flexible duty cycling techniques on the energy constraint sensor nodes. Stated otherwise, low duty cycle nodes should not receive frequent synchronization and control packets if they have no data to send/receive. In this paper, we introduce a Traffic-adaptive MAC protocol (TaMAC) by taking into account the traffic information of the sensor nodes. The protocol dynamically adjusts the duty cycle of the sensor nodes according to their traffic-patterns, thus solving the idle listening and overhearing problems. The traffic-patterns of all sensor nodes are organized and maintained by the coordinator. The TaMAC protocol is supported by a wakeup radio that is used to accommodate emergency and on-demand events in a reliable manner. The wakeup radio uses a separate control channel along with the data channel and therefore it has considerably low power consumption requirements. Analytical expressions are derived to analyze and compare the performance of the TaMAC protocol with the well-known beacon-enabled IEEE 802.15.4 MAC, WiseMAC, and SMAC protocols. The analytical derivations are further validated by simulation results. It is shown that the TaMAC protocol outperforms all other protocols in terms of power consumption and delay. PMID:20703634

  10. Switch Based Opportunistic Spectrum Access for General Primary User Traffic Model

    KAUST Repository

    Gaaloul, Fakhreddine

    2012-06-18

    This letter studies cognitive radio transceiver that can opportunistically use the available channels of primary user (PU). Specifically, we investigate and compare two different opportunistic channel access schemes. The first scheme applies when the secondary user (SU) has access to only one channel. The second scheme, based on channel switching mechanism, applies when the SU has access to multiple channels but can at a given time monitor and access only one channel. For these access schemes, we derive the exact analytical results for the novel performance metrics of average access time and average waiting time under general PU traffic models.

  11. A Survey of Network Optimization Techniques for Traffic Engineering

    OpenAIRE

    Fedrigo, Enrico; Granelli, Fabrizio

    2008-01-01

    TCP/IP represents the reference standard for the implementation of interoperable communication networks. Nevertheless, the layering principle at the basis of interoperability severely limits the performance of data communication networks, thus requiring proper configuration and management in order to provide effective management of traffic flows. This paper presents a brief survey related to network optimization using Traffic Engineering algorithms, aiming at providing additional insight to t...

  12. Traffic flow modeling: a Genealogy

    NARCIS (Netherlands)

    Van Wageningen-Kessels, F.L.M.; Hoogendoorn, S.P.; Vuik, C.; Van Lint, J.W.C.

    2014-01-01

    80 years ago, Bruce Greenshields presented the first traffic flow model at the Annual Meeting of the Highway Research Board. Since then, many models and simulation tools have been developed. We show a model tree with four families of traffic flow models, all descending from Greenshields' model. The

  13. Probabilistic description of traffic flow

    International Nuclear Information System (INIS)

    A stochastic description of traffic flow, called probabilistic traffic flow theory, is developed. The general master equation is applied to relatively simple models to describe the formation and dissolution of traffic congestions. Our approach is mainly based on spatially homogeneous systems like periodically closed circular rings without on- and off-ramps. We consider a stochastic one-step process of growth or shrinkage of a car cluster (jam). As generalization we discuss the coexistence of several car clusters of different sizes. The basic problem is to find a physically motivated ansatz for the transition rates of the attachment and detachment of individual cars to a car cluster consistent with the empirical observations in real traffic. The emphasis is put on the analogy with first-order phase transitions and nucleation phenomena in physical systems like supersaturated vapour. The results are summarized in the flux-density relation, the so-called fundamental diagram of traffic flow, and compared with empirical data. Different regimes of traffic flow are discussed: free flow, congested mode as stop-and-go regime, and heavy viscous traffic. The traffic breakdown is studied based on the master equation as well as the Fokker-Planck approximation to calculate mean first passage times or escape rates. Generalizations are developed to allow for on-ramp effects. The calculated flux-density relation and characteristic breakdown times coincide with empirical data measured on highways. Finally, a brief summary of the stochastic cellular automata approach is given

  14. Road traffic noise and stroke

    DEFF Research Database (Denmark)

    Sørensen, Mette; Hvidberg, Martin; Andersen, Zorana J;

    2011-01-01

    Epidemiological studies suggest that long-term exposure to road traffic noise increases the risk of cardiovascular disorders. The aim of this study was to investigate the relation between exposure to road traffic noise and risk for stroke, which has not been studied before....

  15. Optimizing urban traffic control using a rational agent

    Institute of Scientific and Technical Information of China (English)

    Salvador IBARRA-MARTÍNEZ; José A. CASTÁN-ROCHA; Julio LARIA-MENCHACA

    2014-01-01

    This paper is devoted to developing and evaluating a set of technologies with the objective of designing a method-ology for the implementation of sophisticated traffic lights by means of rational agents. These devices would be capable of op-timizing the behavior of a junction with multiple traffic signals, reaching a higher level of autonomy without losing reliability, accuracy, or efficiency in the offered services. In particular, each rational agent in a traffic signal will be able to analyze the requirements and constraints of the road, in order to know its level of demand. With such information, the rational agent will adapt its light cycles with the view of accomplishing more fluid traffic patterns and minimizing the pollutant environmental emissions produced by vehicles while they are stopped at a red light, through using a case-based reasoning (CBR) adaptation. This paper also integrates a microscopic simulator developed to run a set of tests in order to compare the presented methodology with traditional traffic control methods. Two study cases are shown to demonstrate the efficiency of the introduced approach, increasing vehicular mobility and reducing harmful activity for the environment. For instance, in the first scenario, taking into account the studied traffic volumes, our approach increases mobility by 23%and reduces emissions by 35%. When the roads are managed by sophisticated traffic lights, a better level of service and considerable environmental benefits are achieved, demon-strating the utility of the presented approach.

  16. Assessment of Traffic Noise on Highway Passing from Urban Agglomeration

    Science.gov (United States)

    Vijay, Ritesh; Kori, Chandan; Kumar, Manoj; Chakrabarti, T.; Gupta, Rajesh

    2014-09-01

    Assessment of traffic noise pollution in developing countries is complex due to heterogeneity in traffic conditions like traffic volume, road width, honking, etc. To analyze the impact of such variables, a research study was carried out on a national highway passing from an urban agglomeration. Traffic volume and noise levels (L10, Lmin, Lmax, Leq and L90) were measured during morning and evening peak hours. Contribution of noise by individual vehicle was estimated using passenger car noise unit. Extent of noise pollution and impact of noisy vehicles were estimated using noise pollution level and traffic noise index, respectively. Noise levels were observed to be above the prescribed Indian and International standards. As per audio spectrum analysis of traffic noise, honking contributed an additional 3-4 dB(A) noise. Based on data analysis, a positive relationship was observed between noise levels and honking while negative correlation was observed between noise levels and road width. The study suggests that proper monitoring and analysis of traffic data is required for better planning of noise abatement measures.

  17. Fair Scheduling for Delay-Sensitive VoIP Traffic

    Science.gov (United States)

    Ahmed, Shawish; Jiang, Xiaohong; Horiguchi, Susumu

    With the wide expansion of voice services over the IP networks (VoIP), the volume of this delay sensitive traffic is steadily growing. The current packet schedulers for IP networks meet the delay constraint of VoIP traffic by simply assigning its packets the highest priority. This technique is acceptable as long as the amount of VoIP traffic is relatively very small compared to other non-voice traffic. With the notable expansion of VoIP applications, however, the current packet schedulers will significantly sacrifice the fairness deserved by the non-voice traffic. In this paper, we extend the conventional Deficit Round-Robin (DRR) scheduler by including a packet classifier, a Token Bucket and a resource reservation scheme and propose an integrated packet scheduler architecture for the growing VoIP traffic. We demonstrate through both theoretical analysis and extensive simulation that the new architecture makes it possible for us to significantly improve the fairness to non-voice traffic while still meeting the tight delay requirement of VoIP applications.

  18. Analysis of Trajectory Flexibility Preservation Impact on Traffic Complexity

    Science.gov (United States)

    Idris, Husni; El-Wakil, Tarek; Wing, David J.

    2009-01-01

    The growing demand for air travel is increasing the need for mitigation of air traffic congestion and complexity problems, which are already at high levels. At the same time new information and automation technologies are enabling the distribution of tasks and decisions from the service providers to the users of the air traffic system, with potential capacity and cost benefits. This distribution of tasks and decisions raises the concern that independent user actions will decrease the predictability and increase the complexity of the traffic system, hence inhibiting and possibly reversing any potential benefits. In answer to this concern, the authors proposed the introduction of decision-making metrics for preserving user trajectory flexibility. The hypothesis is that such metrics will make user actions naturally mitigate traffic complexity. In this paper, the impact of using these metrics on traffic complexity is investigated. The scenarios analyzed include aircraft in en route airspace with each aircraft meeting a required time of arrival in a one-hour time horizon while mitigating the risk of loss of separation with the other aircraft, thus preserving its trajectory flexibility. The experiments showed promising results in that the individual trajectory flexibility preservation induced self-separation and self-organization effects in the overall traffic situation. The effects were quantified using traffic complexity metrics, namely dynamic density indicators, which indicated that using the flexibility metrics reduced aircraft density and the potential of loss of separation.

  19. Traffic Based Optimization of Spectrum Sensing in Cognitive Radio Networks

    Directory of Open Access Journals (Sweden)

    Changhua Yao

    2014-01-01

    Full Text Available We propose a more practical spectrum sensing optimization problem in cognitive radio networks (CRN, by considering the data traffic of second user (SU. Compared with most existing work, we do not assume that SU always has packets to transmit; instead, we use the actual data transmitted per second rather than the channel capacity as the achievable throughput, to reformulate the Sensing-Throughput Tradeoff problem. We mathematically analyze the problem of optimal sensing time to maximize the achievable throughput, based on the data traffic of SU. Our model is more general because the traditional Sensing-Throughput Tradeoff model can be seen as a special case of our model. We also prove that the throughput is a concave function of sensing time and there is only one optimal sensing time value which is determined by the data traffic. Simulation results show that the proposed approach outperforms existing methods.

  20. Dissociative Tendencies and Traffic Incidents

    Directory of Open Access Journals (Sweden)

    Valle, Virginia

    2012-01-01

    Full Text Available This paper analyses the relationship between dissociative experiences and road traffic incidents (crashes and traffic tickets in drivers (n=295 from Mar del Plata (Argentina city. A self-report questionnaire was applied to assess traffic crash involvement and sociodemographic variables. Dissociative tendencies were assessed by a modified version of the DES scale. To examine differences in DES scores tests of the difference of means were applied. Drivers who reported to be previously involved in traffic incidents obtained higher puntuations in the dissociative experiences scale than drivers who did not report such events. This result is observed for the total scale and for the three sub-scales (absorption, amnesia and depersonalization. However, differences appeared mainly for minor damage collisions. Further studies are needed to evaluate the role of dissociative tendencies as a risk factor in road traffic safety.

  1. Basic model for traffic interweave

    Science.gov (United States)

    Huang, Ding-wei

    2015-09-01

    We propose a three-parameter traffic model. The system consists of a loop with two junctions. The three parameters control the inflow, the outflow (from the junctions,) and the interweave (in the loop.) The dynamics is deterministic. The boundary conditions are stochastic. We present preliminary results for a complete phase diagram and all possible phase transitions. We observe four distinct traffic phases: free flow, congestion, bottleneck, and gridlock. The proposed model is able to present economically a clear perspective to these four different phases. Free flow and congestion are caused by the traffic conditions in the junctions. Both bottleneck and gridlock are caused by the traffic interweave in the loop. Instead of directly related to conventional congestion, gridlock can be taken as an extreme limit of bottleneck. This model can be useful to clarify the characteristics of traffic phases. This model can also be extended for practical applications.

  2. Traffic Impact Simulation for Road Construction Project

    OpenAIRE

    Yazao Yang; Xiaoni Hao; Junshao Luo

    2012-01-01

    With the increasing traffic contradiction between supply and demand, urban traffic problems have become quite complex. Reasons for traffic congestion have become much more diverse. During the construction of urban road project, the surrounding road network will encounter a huge impact, traffic problems therefore emerged. Simulation is an important means for transport impact assessment, which has an important role for construction traffic impact analysis. Accordingly, traffic simulation i...

  3. An Open-Source Microscopic Traffic Simulator

    OpenAIRE

    Treiber, Martin; Kesting, Arne

    2010-01-01

    We present the interactive Java-based open-source traffic simulator available at www.traffic-simulation.de. In contrast to most closed-source commercial simulators, the focus is on investigating fundamental issues of traffic dynamics rather than simulating specific road networks. This includes testing theories for the spatiotemporal evolution of traffic jams, comparing and testing different microscopic traffic models, modeling the effects of driving styles and traffic rules on the efficiency ...

  4. Traffic Matrix Reloaded: Impact of Routing Changes

    OpenAIRE

    Teixeira, Renata; Duffield, Nick; Rexford, Jennifer; Roughan, Matthew

    2005-01-01

    International audience A traffic matrix represents the load from each ingress point to each egress point in an IP network. Although networks are engineered to tolerate some variation in the traffic matrix, large changes can lead to congested links and poor performance. The variations in the traffic matrix are caused by statistical fluc-tuations in the traffic entering the network and shifts in where the traffic leaves the network. For an accurate view of how the traffic matrix evolves over...

  5. Simulation of Genetic Algorithm: Traffic Light Efficiency

    OpenAIRE

    Lienert, Eric

    2015-01-01

    Traffic is a problem in many urban areas worldwide. Traffic flow is dictated by certain devices such as traffic lights. The traffic lights signal when each lane is able to pass through the intersection. Often, static schedules interfere with ideal traffic flow. The purpose of this project was to find a way to make intersections controlled with traffic lights more efficient. This goal was accomplished through the creation of a genetic algorithm, which enhances an input algorithm through geneti...

  6. An Advanced Fuzzy Logic Based Traffic Controller

    OpenAIRE

    Bilal Ahmed Khan; Nai Shyan Lai

    2014-01-01

    Traffic light plays an important role in the urban traffic management. Therefore, it is necessary to improve the traffic controller for effective traffic management and better traffic flow leading to greener environment. In this paper, an advanced and intelligent traffic light controller is proposed, utilising the fuzzy logic technology and image processing technique. A fuzzy logic control has been implemented to provide the attribute of intelligence to the system. For real-time image acquisi...

  7. Traffic information computing platform for big data

    International Nuclear Information System (INIS)

    Big data environment create data conditions for improving the quality of traffic information service. The target of this article is to construct a traffic information computing platform for big data environment. Through in-depth analysis the connotation and technology characteristics of big data and traffic information service, a distributed traffic atomic information computing platform architecture is proposed. Under the big data environment, this type of traffic atomic information computing architecture helps to guarantee the traffic safety and efficient operation, more intelligent and personalized traffic information service can be used for the traffic information users

  8. Web application for traffic flow forecasting

    OpenAIRE

    Dubravac, Dragan

    2015-01-01

    Disturbances in traffic on highways usually lead to an increase in traffic flow density or even traffic jams. The main goal of the diploma thesis is to produce an application that will predict traffic flow and traffic jams on any given date and time based on traffic flow in the past. By using an estimated desired speed the traffic information gained from flow counters we can forecast the evolution of traffic jams. The application presents a graph that represents the number of vehicles on a...

  9. Traffic information computing platform for big data

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Zongtao, E-mail: ztduan@chd.edu.cn; Li, Ying, E-mail: ztduan@chd.edu.cn; Zheng, Xibin, E-mail: ztduan@chd.edu.cn; Liu, Yan, E-mail: ztduan@chd.edu.cn; Dai, Jiting, E-mail: ztduan@chd.edu.cn; Kang, Jun, E-mail: ztduan@chd.edu.cn [Chang' an University School of Information Engineering, Xi' an, China and Shaanxi Engineering and Technical Research Center for Road and Traffic Detection, Xi' an (China)

    2014-10-06

    Big data environment create data conditions for improving the quality of traffic information service. The target of this article is to construct a traffic information computing platform for big data environment. Through in-depth analysis the connotation and technology characteristics of big data and traffic information service, a distributed traffic atomic information computing platform architecture is proposed. Under the big data environment, this type of traffic atomic information computing architecture helps to guarantee the traffic safety and efficient operation, more intelligent and personalized traffic information service can be used for the traffic information users.

  10. Traffic Survey Techniques Study Based on the Freight Vehicles GPS Data%基于货运车辆GPS数据的交通调查技术研究

    Institute of Scientific and Technical Information of China (English)

    詹起林; 高峻; 王磊

    2011-01-01

    基于GPS轨迹点与道路网络拓扑数据,利用GIS技术进行OD点和交通通道的调查研究.利用货运车辆GPS轨迹数据,分析轨迹点的时间、速度及其空间分布特征,实验并确定合理的阈值过滤出点簇,生成OD点;用轨迹点捕获含有拓扑关系的临近路段,通过最短路径算法生成货运车辆沿道路的线型轨迹,最终获得完整的货运车辆出行通道调查数据.与传统交通调查方法相比,该方法的组织实施环节大大减少,调查数据和成果更加客观可靠,是一种通过信息技术进行交通调查研究的全新尝试.%Traffic survey is the foundation of urban transportation plan, construction and management. In the traditional study of traffic survey,a lot of manpower and material resources are required. After studying the research progress in the traffic survey,based on the GPS track points, road network topology data, and GIS technology, traffic technology research of OD points and traffic channel was realized in this paper. 1) By using freight vehicles GPS track data under customs' monitoring, the time, speed and mileage information of track point, and the spatial distribution characteristics about these track points were analyzed, by determining a reasonable threshold to filter out the cluster of stop points, and then traffic OD points were generated. 2) GPS track points can be captured to the nearest road, it can obtain the linear track of freight vehicles travelling through the shortest path algorithm. Additional the road sections without any track points recorded were collected to produce a complete vehicle traffic channel travel during freight vehicles driving. 3) In the end,it calculated the channel operation data combined with track points GPS attribute information on the channel. The traffic survey technology was used in the fourth comprehensive traffic survey in Shanghai, ultimately got a number of achievements that reflect traffic conditions, for example the OD

  11. Graceful Degradation of Air Traffic Operations

    CERN Document Server

    Gariel, Maxime

    2008-01-01

    The introduction of new technologies and concepts of operation in the air transportation system is not possible, unless they can be proven not to adversely affect the system operation under not only nominal, but also degraded conditions. In extreme scenarios, degraded operations due to partial or complete technological failures should never endanger system safety. Many past system evolutions, whether ground-based or airborne, have been based on trial-and-error, and system safety was addressed only after a specific event yielded dramatic or near- dramatic consequences. Future system evolutions, however, must leverage available computation, prior knowledge and abstract reasoning to anticipate all possible system degradations and prove that such degradations are graceful and safe. This paper is concerned with the graceful degradation of high-density, structured arrival traffic against partial or complete surveillance failures. It is shown that for equal performance requirements, some traffic configurations might...

  12. The Physics of Traffic and Regional Development

    CERN Document Server

    Helbing, Dirk

    2013-01-01

    This contribution summarizes and explains various principles from physics which are used for the simulation of traffic flows in large street networks, the modeling of destination, transport mode, and route choice, or the simulation of urban growth and regional development. The methods stem from many-particle physics, from kinetic gas theory, or fluiddynamics. They involve energy and entropy considerations, transfer the law of gravity, apply cellular automata and require methods from evolutionary game theory. In this way, one can determine interaction forces among driver-vehicle units, reproduce breakdowns of traffic including features of synchronized congested flow, or understand changing usage patterns of alternative roads. One can also describe daily activity patterns based on decision models, simulate migration streams, and model urban growth as a particular kind of aggregation process.

  13. CQ Switch Analysis under Traffic Overload

    Directory of Open Access Journals (Sweden)

    I. Maljević

    2011-06-01

    Full Text Available An analysis of 2x2 crossbar packet switch with buffers at crosspoints and round robin scheduling algorithm is presented in this paper. The analysis is performed for a non-admissible traffic pattern, where output ports are overloaded. The case of full offered load is observed and output ports are loaded with packets that have different arrival probabilities. In addition to the parameters that are commonly observed in such an analysis (throughput and average packet delay, memory requirements for the implementation of the buffer, as well as fair representation when servicing the buffer - the so-called fairness are also analyzed. The results show that even for a switch with a small number of ports very large buffers should be implemented, if we want to achieve satisfactory performance under traffic overload.

  14. A COMPACT MODEL FOR PREDICTING ROAD TRAFFIC NOISE

    Directory of Open Access Journals (Sweden)

    R. Golmohammadi ، M. Abbaspour ، P. Nassiri ، H. Mahjub

    2009-07-01

    Full Text Available Noise is one of the most important sources of pollution in the metropolitan areas. The recognition of road traffic noise as one of the main sources of environmental pollution has led to develop models that enable us to predict noise level from fundamental variables. Traffic noise prediction models are required as aids in the design of roads and sometimes in the assessment of existing, or envisaged changes in, traffic noise conditions. The purpose of this study was to design a prediction road traffic noise model from traffic variables and conditions of transportation in Iran.This paper is the result of a research conducted in the city of Hamadan with the ultimate objective of setting up a traffic noise model based on the traffic conditions of Iranian cities. Noise levels and other variables have been measured in 282 samples to develop a statistical regression model based on A-weighted equivalent noise level for Iranian road condition. The results revealed that the average LAeq in all stations was 69.04± 4.25 dB(A, the average speed of vehicles was 44.57±11.46 km/h and average traffic load was 1231.9 ± 910.2 V/h.The developed model has seven explanatory entrance variables in order to achieve a high regression coefficient (R2=0.901. Comparing means of predicted and measuring equivalent sound pressure level (LAeq showed small difference less than -0.42 dB(A and -0.77 dB(A for Tehran and Hamadan cities, respectively. The suggested road traffic noise model can be effectively used as a decision support tool for predicting equivalent sound pressure level index in the cities of Iran.

  15. Modeling a bus through a sequence of traffic lights

    Science.gov (United States)

    Villalobos, Jorge; Muñoz, Víctor; Rogan, José; Zarama, Roberto; Penagos, Juan Felipe; Toledo, Benjamín; Valdivia, Juan Alejandro

    2015-07-01

    We propose a model of a bus traveling through a sequence of traffic lights, which is required to stop between the traffic signals to pick up passengers. A two dimensional model, of velocity and traveled time at each traffic light, is constructed, which shows non-trivial and chaotic behaviors for realistic city traffic parameters. We restrict the parameter values where these non-trivial and chaotic behaviors occur, by following analytically and numerically the fixed points and period 2 orbits. We define conditions where chaos may arise by determining regions in parameter space where the maximum Lyapunov exponent is positive. Chaos seems to occur as long as the ratio of the braking and accelerating capacities are greater than about ˜3.

  16. Framework for Traffic Congestion Management

    Directory of Open Access Journals (Sweden)

    Mahmud Hassan TALUKDAR

    2013-06-01

    Full Text Available Traffic Congestion is one of many serious global problems in all great cities resulted from rapid urbanization which always exert negative externalities upon society. The solution of traffic congestion is highly geocentric and due to its heterogeneous nature, curbing congestion is one of the hard tasks for transport planners. It is not possible to suggest unique traffic congestion management framework which could be absolutely applied for every great cities. Conversely, it is quite feasible to develop a framework which could be used with or without minor adjustment to deal with congestion problem. So, the main aim of this paper is to prepare a traffic congestion mitigation framework which will be useful for urban planners, transport planners, civil engineers, transport policy makers, congestion management researchers who are directly or indirectly involved or willing to involve in the task of traffic congestion management. Literature review is the main source of information of this study. In this paper, firstly, traffic congestion is defined on the theoretical point of view and then the causes of traffic congestion are briefly described. After describing the causes, common management measures, using world- wide, are described and framework for supply side and demand side congestion management measures are prepared.

  17. Planning and managing rural recreational traffic flows: why the future can’t be more like the past

    OpenAIRE

    Jaarsma, C.F.; Vries, de, P.M.; Beunen, R.

    2009-01-01

    The increasing popularity of rural tourism can cause traffic related problems at certain areas. Traffic congestion and parking problems are likely to occur as the infrastructure at these countryside destinations is seldom capable of dealing with the growing number of cars. Values which make the sites attractive to visitors can become under pressure and car traffic can also have negative effects on natural values. To prevent for such impacts, recreational traffic management is required. Recrea...

  18. Traffic Light Detection at Night

    DEFF Research Database (Denmark)

    Jensen, Morten Bornø; Philipsen, Mark Philip; Bahnsen, Chris;

    2015-01-01

    Traffic light recognition (TLR) is an integral part of any in- telligent vehicle, it must function both at day and at night. However, the majority of TLR research is focused on day-time scenarios. In this paper we will focus on detection of traffic lights at night and evalu- ate the performance...... of three detectors based on heuristic models and one learning-based detector. Evaluation is done on night-time data from the public LISA Traffic Light Dataset. The learning-based detector out- performs the model-based detectors in both precision and recall. The learning-based detector achieves an average...

  19. Linearized Theory of Traffic Flow

    CERN Document Server

    Cohan, Tal

    2014-01-01

    The equation of motion of a general class of macroscopic traffic flow models is linearized around a steady uniform flow. A closed-form solution of a boundary-initial value problem is obtained, and it is used to describe several phenomena. Specifically, the scenarios examined involve a smooth velocity field in stop-and-go traffic, a discontinuous velocity field with shock waves in a traffic light problem, and discontinuous displacement fields in a problem where a single platoon of vehicles splits into two, and later merges back into one.

  20. Real-Time Corrected Traffic Correlation Model for Traffic Flow Forecasting

    OpenAIRE

    Lu, Hua-pu; Sun, Zhi-yuan; Qu, Wen-cong; Wang, Ling

    2015-01-01

    This paper focuses on the problems of short-term traffic flow forecasting. The main goal is to put forward traffic correlation model and real-time correction algorithm for traffic flow forecasting. Traffic correlation model is established based on the temporal-spatial-historical correlation characteristic of traffic big data. In order to simplify the traffic correlation model, this paper presents correction coefficients optimization algorithm. Considering multistate characteristic of traffic ...

  1. Spatiotemporal traffic-flow dependency and short-term traffic forecasting

    OpenAIRE

    Yang Yue; Anthony Gar-On Yeh

    2008-01-01

    Short-term traffic forecasting is playing an increasing role in modern transport management. Although many short-term traffic forecasting methods have been explored, the spatiotemporal dependency of traffic flow, an important characteristic of traffic dynamics that can benefit the forecasting of traffic changes, is often neglected in short-term traffic forecasting. This paper first investigates the spatiotemporal dependency of traffic flow using cross-correlation analysis and then discusses i...

  2. Transition Characteristic Analysis of Traffic Evolution Process for Urban Traffic Network

    OpenAIRE

    Longfei Wang; Hong Chen; Yang Li

    2014-01-01

    The characterization of the dynamics of traffic states remains fundamental to seeking for the solutions of diverse traffic problems. To gain more insights into traffic dynamics in the temporal domain, this paper explored temporal characteristics and distinct regularity in the traffic evolution process of urban traffic network. We defined traffic state pattern through clustering multidimensional traffic time series using self-organizing maps and construct a pattern transition network model tha...

  3. A Two-Stage Fuzzy Logic Control Method of Traffic Signal Based on Traffic Urgency Degree

    OpenAIRE

    Yan Ge

    2014-01-01

    City intersection traffic signal control is an important method to improve the efficiency of road network and alleviate traffic congestion. This paper researches traffic signal fuzzy control method on a single intersection. A two-stage traffic signal control method based on traffic urgency degree is proposed according to two-stage fuzzy inference on single intersection. At the first stage, calculate traffic urgency degree for all red phases using traffic urgency evaluation module and select t...

  4. Automated Conflict Resolution For Air Traffic Control

    Science.gov (United States)

    Erzberger, Heinz

    2005-01-01

    The ability to detect and resolve conflicts automatically is considered to be an essential requirement for the next generation air traffic control system. While systems for automated conflict detection have been used operationally by controllers for more than 20 years, automated resolution systems have so far not reached the level of maturity required for operational deployment. Analytical models and algorithms for automated resolution have been traffic conditions to demonstrate that they can handle the complete spectrum of conflict situations encountered in actual operations. The resolution algorithm described in this paper was formulated to meet the performance requirements of the Automated Airspace Concept (AAC). The AAC, which was described in a recent paper [1], is a candidate for the next generation air traffic control system. The AAC's performance objectives are to increase safety and airspace capacity and to accommodate user preferences in flight operations to the greatest extent possible. In the AAC, resolution trajectories are generated by an automation system on the ground and sent to the aircraft autonomously via data link .The algorithm generating the trajectories must take into account the performance characteristics of the aircraft, the route structure of the airway system, and be capable of resolving all types of conflicts for properly equipped aircraft without requiring supervision and approval by a controller. Furthermore, the resolution trajectories should be compatible with the clearances, vectors and flight plan amendments that controllers customarily issue to pilots in resolving conflicts. The algorithm described herein, although formulated specifically to meet the needs of the AAC, provides a generic engine for resolving conflicts. Thus, it can be incorporated into any operational concept that requires a method for automated resolution, including concepts for autonomous air to air resolution.

  5. Traffic visualization - applying information visualization techniques to enhance traffic planning

    OpenAIRE

    Picozzi, Matteo; Verdezoto, Nervo; Pouke, Matti; Vatjus-Anttila, Jarkko; Quigley, Aaron John

    2013-01-01

    In this paper, we present a space-time visualization to provide city’s decision-makers the ability to analyse and uncover important “city events” in an understandable manner for city planning activities. An interactive Web mashup visualization is presented that integrates several visualization techniques to give a rapid overview of traffic data. We illustrate our approach as a case study for traffic visualization systems, using datasets from the city of Oulu that can be extended to other city...

  6. It Leaks More Than You Think: Fingerprinting Users from Web Traffic Analysis

    Directory of Open Access Journals (Sweden)

    Xujing Huang

    2015-12-01

    Full Text Available We show how, in real-world web applications, confidential information about user identities can be leaked through “non-intuitive communications”, in particular web traffic which appear to be not related to the user information. In fact, our experiments on Google users demonstrate that even Google accounts are vulnerable on traffic attacks against user identities, using packet sizes and directions. And this work shows this kind of non-intuitive communication can leak even more information about user identities than the traffic explicitly using confidential information. Our work highlights possible side-channel leakage through cookies and more generally discovers fingerprints in web traffic which can improve the probability of correctly guessing a user identity. Our analysis is motivated by Hidden Markov Model, distance metric and guessing probability to analyse and evaluate these side-channel vulnerabilities.

  7. Traffic Based Optimization of Spectrum Sensing in Cognitive Radio Networks

    OpenAIRE

    Changhua Yao; Qihui Wu; Linfang Zhou

    2014-01-01

    We propose a more practical spectrum sensing optimization problem in cognitive radio networks (CRN), by considering the data traffic of second user (SU). Compared with most existing work, we do not assume that SU always has packets to transmit; instead, we use the actual data transmitted per second rather than the channel capacity as the achievable throughput, to reformulate the Sensing-Throughput Tradeoff problem. We mathematically analyze the problem of optimal sensing time to maximize the ...

  8. Understanding the T2 traffic in CMS during Run-1

    Science.gov (United States)

    T, Wildish

    2015-12-01

    In the run-up to Run-1 CMS was operating its facilities according to the MONARC model, where data-transfers were strictly hierarchical in nature. Direct transfers between Tier-2 nodes was excluded, being perceived as operationally intensive and risky in an era where the network was expected to be a major source of errors. By the end of Run-1 wide-area networks were more capable and stable than originally anticipated. The original data-placement model was relaxed, and traffic was allowed between Tier-2 nodes. Tier-2 to Tier-2 traffic in 2012 already exceeded the amount of Tier-2 to Tier-1 traffic, so it clearly has the potential to become important in the future. Moreover, while Tier-2 to Tier-1 traffic is mostly upload of Monte Carlo data, the Tier-2 to Tier-2 traffic represents data moved in direct response to requests from the physics analysis community. As such, problems or delays there are more likely to have a direct impact on the user community. Tier-2 to Tier-2 traffic may also traverse parts of the WAN that are at the 'edge' of our network, with limited network capacity or reliability compared to, say, the Tier-0 to Tier-1 traffic which goes the over LHCOPN network. CMS is looking to exploit technologies that allow us to interact with the network fabric so that it can manage our traffic better for us, this we hope to achieve before the end of Run-2. Tier-2 to Tier-2 traffic would be the most interesting use-case for such traffic management, precisely because it is close to the users' analysis and far from the 'core' network infrastructure. As such, a better understanding of our Tier-2 to Tier-2 traffic is important. Knowing the characteristics of our data-flows can help us place our data more intelligently. Knowing how widely the data moves can help us anticipate the requirements for network capacity, and inform the dynamic data placement algorithms we expect to have in place for Run-2. This paper presents an analysis of the CMS Tier-2 traffic during Run 1.

  9. A Useful Metaheuristic for Dynamic Channel Assignment in Mobile Cellular Systems

    Directory of Open Access Journals (Sweden)

    Deepak Kumar Singh

    2012-09-01

    Full Text Available The prime objective of a Channel Assignment Problem (CAP is to assign appropriate number of required channels to each cell in a way to achieve both efficient frequency spectrum utilization and minimization of interference effects (by satisfying a number of channel reuse constraints. Dynamic Channel Assignment (DCA assigns the channels to the cells dynamically according to traffic demand, and hence, can provide higher capacity (or lower call blocking probability, fidelity and quality of service than the fixed assignment schemes. Channel assignment algorithms are formulated as combinatorial optimization problems and are NP-hard. Devising a DCA, that is practical, efficient, and which can generate high quality assignments, is challenging. Though Metaheuristic Search techniques like Evolutionary Algorithms, Differential Evolution, Particle Swarm Optimization prove effective in the solution of Fixed Channel Assignment (FCA problems but they still require high computational time and therefore may be inefficient for DCA. A number of approaches have been proposed for the solution of DCA problem but the high complexity of these proposed approaches makes them unsuitable/less efficient for practical use. Therefore, this paper presents an effective and efficient Hybrid Discrete Binary Differential Evolution Algorithm (HDB-DE for the solution of DCA Problem

  10. Active plasmonics in WDM traffic switching applications

    Science.gov (United States)

    Papaioannou, Sotirios; Kalavrouziotis, Dimitrios; Vyrsokinos, Konstantinos; Weeber, Jean-Claude; Hassan, Karim; Markey, Laurent; Dereux, Alain; Kumar, Ashwani; Bozhevolnyi, Sergey I.; Baus, Matthias; Tekin, Tolga; Apostolopoulos, Dimitrios; Avramopoulos, Hercules; Pleros, Nikos

    2012-09-01

    With metal stripes being intrinsic components of plasmonic waveguides, plasmonics provides a ``naturally'' energy-efficient platform for merging broadband optical links with intelligent electronic processing, instigating a great promise for low-power and small-footprint active functional circuitry. The first active Dielectric-Loaded Surface Plasmon Polariton (DLSPP) thermo-optic (TO) switches with successful performance in single-channel 10 Gb/s data traffic environments have led the inroad towards bringing low-power active plasmonics in practical traffic applications. In this article, we introduce active plasmonics into Wavelength Division Multiplexed (WDM) switching applications, using the smallest TO DLSPP-based Mach-Zehnder interferometric switch reported so far and showing its successful performance in 4×10 Gb/s low-power and fast switching operation. The demonstration of the WDM-enabling characteristics of active plasmonic circuits with an ultra-low power × response time product represents a crucial milestone in the development of active plasmonics towards real telecom and datacom applications, where low-energy and fast TO operation with small-size circuitry is targeted.

  11. Inferring traffic burstiness by sampling the buffer occupancy

    NARCIS (Netherlands)

    Mandjes, Michel; Meent, van de Remco

    2004-01-01

    Common practice to determine the required bandwidth capacity for a network link is to measure the 5 minute average link load and then add a safety margin to cater for traffic bursts on small time-scales. Because of the substantial measurement effort required to appropriately determine the effect of

  12. Estimating Emissions from Railway Traffic

    DEFF Research Database (Denmark)

    Jørgensen, Morten W.; Sorenson, Spencer C.

    Several parameters of importance for estimating emissions from railway traffic are discussed, and typical results presented. Typical emissions factors from diesel engines and electrical power generation are presented, and the effect of differences in national electrical generation sources...

  13. 2013 Traffic Safety Culture Index

    Science.gov (United States)

    ... endorse products or manufacturers. ©2014, AAA Foundation for Traffic Safety Introduction In the quarter century from 1988 through 2012, the lives of 1,018,581 men, women, and children have ended violently as the result ...

  14. Assessment of Traffic Noise Impacts

    DEFF Research Database (Denmark)

    Rich, Jeppe Husted; Nielsen, Otto Anker

    2004-01-01

    A steady growth in traffic intensities in most urban areas throughout the world has forced planners and politicians to seriously consider the resulting environmental impact, such as traffic noise, accidents and air pollution. The assessment of such negative factors is needed in order to reveal...... the true social benefit of infrastructure plans. The paper presents a noise assessment model for the Copenhagen region, which brings together GIS technology and non-linear hedonic regression models to reveal the implicit costs of traffic noise measured as the marginal percentage loss in property values...... with respect to the decibel traffic noise. The model distinguishes between houses and apartments and shows that the ability to include refined accessibility variables have significant impact on estimated prices....

  15. Estimating Emissions from Railway Traffic

    DEFF Research Database (Denmark)

    Jørgensen, Morten W.; Sorenson, Spencer C.

    1998-01-01

    Several parameters of importance for estimating emissions from railway traffic are discussed, and typical results presented. Typical emissions factors from diesel engines and electrical power generation are presented, and the effect of differences in national electrical generation sources...

  16. A multiagent urban traffic simulation

    CERN Document Server

    Tranouez, Pierrick; Langlois, Patrice

    2012-01-01

    We built a multiagent simulation of urban traffic to model both ordinary traffic and emergency or crisis mode traffic. This simulation first builds a modeled road network based on detailed geographical information. On this network, the simulation creates two populations of agents: the Transporters and the Mobiles. Transporters embody the roads themselves; they are utilitarian and meant to handle the low level realism of the simulation. Mobile agents embody the vehicles that circulate on the network. They have one or several destinations they try to reach using initially their beliefs of the structure of the network (length of the edges, speed limits, number of lanes etc.). Nonetheless, when confronted to a dynamic, emergent prone environment (other vehicles, unexpectedly closed ways or lanes, traffic jams etc.), the rather reactive agent will activate more cognitive modules to adapt its beliefs, desires and intentions. It may change its destination(s), change the tactics used to reach the destination (favorin...

  17. Automatic Traffic Recorder (ATR) Stations

    Data.gov (United States)

    Department of Homeland Security — The data included in the GIS Traffic Stations Version database have been assimilated from station description files provided by FHWA for Weigh-in-Motion (WIM), and...

  18. Lagrangian Multi-Class Traffic State Estimation

    NARCIS (Netherlands)

    Yuan, Y.

    2013-01-01

    Road traffic is important to everybody in the world. People travel and commute everyday. For those who travel by cars (or other types of road vehicles), traffic congestion is a daily experience. One essential goal of traffic researchers is to reduce traffic congestion and to improve the whole traffi

  19. Assessing Vessel Traffic Service Operator Situation Awareness

    NARCIS (Netherlands)

    Wiersma, J.W.F.

    2010-01-01

    This thesis describes my study of situation awareness assessment of Vessel Traffic Service (VTS) operators. VTS operators are the traffic controllers on the water. They are responsible for a safe and efficient handling of vessel traffic. They monitor traffic, provide information on request and coord

  20. Stochastic control of traffic patterns

    DEFF Research Database (Denmark)

    Gaididei, Yuri B.; Gorria, Carlos; Berkemer, Rainer;

    2013-01-01

    A stochastic modulation of the safety distance can reduce traffic jams. It is found that the effect of random modulation on congestive flow formation depends on the spatial correlation of the noise. Jam creation is suppressed for highly correlated noise. The results demonstrate the advantage of...... heterogeneous performance of the drivers in time as well as individually. This opens the possibility for the construction of technical tools to control traffic jam formation....

  1. Stochastic control of traffic patterns

    OpenAIRE

    Gaididei, Yuri B.; Gorria, Carlos; Berkemer, Rainer; Christiansen, Peter L.; Kawamoto, Atsushi; Sørensen, Mads Peter; Starke, Jens

    2013-01-01

    A stochastic modulation of the safety distance can reduce traffic jams. It is found that the effect of random modulation on congestive flow formation depends on the spatial correlation of the noise. Jam creation is suppressed for highly correlated noise. The results demonstrate the advantage of heterogeneous performance of the drivers in time as well as individually. This opens the possibility for the construction of technical tools to control traffic jam formation.

  2. Matlab Toolbox for Traffic Simulations

    Czech Academy of Sciences Publication Activity Database

    Dohnal, Pavel

    Prague : Czech Technical University in Prague, 2007, s. 1-4. [International Student Conference on Electrical Engineering - Poster 2007 /11./. Prague (CZ), 17.05.2007] R&D Projects: GA MDS 1F43A/003/120; GA AV ČR 1ET100750401 Institutional research plan: CEZ:AV0Z10750506 Keywords : traffic simulator * Aimsun * traffic quantities Subject RIV: JC - Computer Hardware ; Software

  3. Reports on internet traffic statistics

    OpenAIRE

    Hoogesteger, Martijn; Oliveira Schmidt, de, Ricardo; Sperotto, Anna; Pras, Aiko

    2013-01-01

    Internet traffic statistics can provide valuable information to network analysts and researchers about the way nowadays networks are used. In the past, such information was provided by Internet2 in a public website called Internet2 NetFlow: Weekly Reports. The website reported traffic statistics from the Abilene network on a weekly basis. At that time, the network connected 230 research institutes with a 10Gb/s link. Although these reports were limited to the behavior of the Albeline's users,...

  4. Estimating emissions from railway traffic

    Energy Technology Data Exchange (ETDEWEB)

    Joergensen, M.W.; Sorenson, C.

    1997-07-01

    The report discusses methods that can be used to estimate the emissions from various kinds of railway traffic. The methods are based on the estimation of the energy consumption of the train, so that comparisons can be made between electric and diesel driven trains. Typical values are given for the necessary traffic parameters, emission factors, and train loading. Detailed models for train energy consumption are presented, as well as empirically based methods using average train speed and distance between stop. (au)

  5. Hybrid Traffic Management Model for Multi-Protocol Label Switching Network

    OpenAIRE

    E.R. Naganathan; Rajagopalan, S.

    2011-01-01

    Problem statement: MPLS is a highly scalable, protocol agnostic and data-carrying mechanism. Traffic engineering is the major research area in MPLS due to the emerging requirements of MPLS and the internet usage. A major objective of traffic engineering is to minimize or eliminate high-loss situations. Another goal of traffic engineering is to balance the Quality of Service (QoS) against the cost of operating and maintaining the network. Approach: This study proposes a hybrid model for effect...

  6. OIS - An optical information system for road traffic measurement and management

    OpenAIRE

    Dalaff, Carsten; Reulke, Ralf; Ruhé, Martin; Schischmanow, Adrian; Schlotzhauer, Gerald

    2003-01-01

    OIS is a new Optical Information System for road traffic observation and management. The complete system architecture from the sensor for automatic traffic detection up to the treffic light management for a wide area is designed under the requirements of an intelligent transportation system. Particular features of this system are the vision sensors with integrated computational and real-time capabilities, real-time algorithms for image processing and a new approach for dynamic traffic light...

  7. Present and future methodology for the implementation of decision support systems for traffic management

    OpenAIRE

    Casas Vilaró, Jordi; Torday, Alexandre; Perarnau i Codina, Josep; Breen, M; Ruiz de Villa, Alex

    2013-01-01

    Real-time predictions are an indispensable requirement for traffic management in order to be able to evaluate the effects of different available strategies or policies. The combination of predicting the state of the network and the evaluation of different traffic management strategies in the short term future allows system managers to anticipate the effects of traffic control strategies ahead of time in order to mitigate the effect of congestion. This paper presents the current...

  8. Minimizing the Disruptive Effects of Prospective Memory in Simulated Air Traffic Control

    OpenAIRE

    Loft, Shayne; Smith, Rebekah E.; Remington, Roger

    2013-01-01

    Prospective memory refers to remembering to perform an intended action in the future. Failures of prospective memory can occur in air traffic control. In two experiments, we examined the utility of external aids for facilitating air traffic management in a simulated air traffic control task with prospective memory requirements. Participants accepted and handed-off aircraft and detected aircraft conflicts. The prospective memory task involved remembering to deviate from a routine operating pro...

  9. Traffic accident injuries in a referral Orthopedic Hospital in North West of Iran during summer 2009

    OpenAIRE

    Amir Mohammad Navali; Firoozeh Pouyandeh

    2015-01-01

    Introduction: Road traffic injuries are a major public health problem, requiring huge efforts for effective and sustainable prevention. Because of the high occurrence of traffic accidents in Iran, basic data acquisition is highly needed to implement prevention plans. The present research is conducted as an epidemiological study of the traffic accident victims referred to a referral orthopedic center in North West of Iran. Methods: A cross-sectional study was conducted during a 3 months period...

  10. Fastlane: Traffic flow modeling and multi-class dynamic traffic management

    NARCIS (Netherlands)

    Schreiter, T.; Van Wageningen-Kessels, F.L.M.; Yuan, Y.; Van Lint, J.W.C.; Hoogendoorn, S.P.

    2012-01-01

    Dynamic Traffic Management (DTM) aims to improve traffic conditions. DTM usually consists of two steps: first the current traffic is estimated, then appropriate control actions are determined based on that estimate. In order to estimate and control the traffic, a suitable traffic flow model that rep

  11. Counter-based Traffic Management Scheme for Vehicular Networks

    Directory of Open Access Journals (Sweden)

    Tarun Prakash

    2011-06-01

    Full Text Available Vehicles traffic congestion on the road is reflected as delays while traveling. This congestion has a number of negative effects such as energy consumption, wastage of time and increased tailpipes emission of idling vehicles probably bad for our health. Vehicular congestion has become the serious problem and it is getting worse day by day as the growth of the vehicles significantly increased. In this paper, we proposed a novel counter approach to avoid such vehicular congestion on the road. We have also proposed a path selection algorithm that ensures best path suggestion to vehicles in terms of reduction in trip time and less fuel consumption during whole trip. The whole traffic management solution is combination of "stochastic turn" (i.e. vehicles choose a new direction at each intersection or any other way point and path planning (i.e. origin and destination of the vehicle required in advance that ensured by suggested path selection algorithm. In the later part of this paper simulation results prove the effectiveness of our traffic management scheme in terms of reducing traffic congestion on the road. In addition, this scheme utilizes best of the resources and characteristics of vehicular networks to provide less congested path prediction and also smoothed flow of traffic for vehicles in high density vehicular traffic conditions.

  12. TRAFFIC RETIMING SYSTEM USING IMAGE PROCESSING

    OpenAIRE

    Tanmayi Jain*

    2015-01-01

    One of the main problems in cities is traffic, this paper proposed new solution to traffic control. The main design concept of this project is to control the traffic automatically. System is made more efficient with addition of intelligence in term of artificial vision, using image processing techniques to estimate actual road traffic and compute time, each time for every road before enabling the signal. This model is resemblance of traditional traffic police man who takes better ...

  13. MEASURES TO IMPROVE THE TRAFFIC MANAGEMENT

    OpenAIRE

    Дульгер, В.; Пиндюрина, Е.; Муратова, А.

    2012-01-01

    Everybody knows the volume of traffic on today's roads is increasing, thereby, reducing the capacity of the road which causes delays and congestion. "Traffic Management" is the termed as "ways and measures of adjusting, accommodating or adapting the use of road space available without building new ones". The key objective of introducing traffic management measures is to achieve one of the following: improve the flow of traffic, or specific types of traffic (e.g. bus / cycle priority measures)...

  14. Formation and Propagation of Local Traffic Jam

    OpenAIRE

    Hong-sheng Qi; Dian-hai Wang; Peng Chen

    2013-01-01

    Large scale traffic congestion often stems from local traffic jam in single road or intersection. In this paper, macroscopic method was used to explore the formation and propagation of local traffic jam. It is found that (1) the propagation of traffic jam can be seen as the propagation of traffic signal parameters, that is, virtual split and virtual green time; (2) for a road with endogenous flow, entrance location influences the jam propagation. With the same demand (upstream links flow and ...

  15. Study on the Traffic Congestion in Beijing

    OpenAIRE

    Ma Xiaofei

    2013-01-01

    As the the rapid growth of city economy, a traffic congestion has become a common sight in almost every big city. On the surface, the infrastructure construction is incompatible with the rapid expansion of the city cars. In fact,the root cause lies in the careless and easy style of management of traffic which leads to the low traffic efficiency. This study mainly describes the traffic system, the causes of traffic congestion, discussing on the optimization to ...

  16. Business scenarios for Virtual Traffic Lights

    OpenAIRE

    Rathe, Eirik Auran

    2015-01-01

    Virtual Traffic Lights (VTL) is a novel technology which aims to provide ubiquitous traffic intersection control by removing physical traffic lights and placing them inside vehicles. It has already been proven, through simulation, that VTL is capable of significantly increasing traffic flow and reduce CO2-emissions and fuel consumption for individual vehicles. To ensure a streamlined transition from traditional physical traffic lights to VTL, several issues must be addressed. This thesis ...

  17. Data reduction in modeled packet traffic

    OpenAIRE

    Mehrabian, Maryam

    2012-01-01

        Within Ericsson there is a continuous activity of traffic modeling. Traffic modeling is a practice to analyze traffic patterns and determine necessary resources to handle it optimally. This activity focuses on gathering and analyzing live network measurements, implementing and presenting traffic models. One example of concept in packet traffic modeling is transmission object log which is an aggregation of packet data traces from a measured network over a transmission period. These trace l...

  18. Dual use of LED traffic signal system

    OpenAIRE

    Cheung, SW; Yang, ES; Tam, YY; Man, CW; D. Yang

    1999-01-01

    The dual use, signaling and communication, of LED traffic signal system is described and analyzed. The primary function of a traffic light system is to give traffic and pedestrian signals. A prototype of LED traffic signal head is developed to perform a secondary function: communication. A wireless communication link is set up using the LED traffic signal head as the transmitter. The LEDs are modulated to transmit information-carrying light. The receiver uses a silicon photodiode to detect th...

  19. Traffic Signal Using Smart Agent System

    OpenAIRE

    Cheonshik Kim; You S. Hong

    2008-01-01

    In this research, we propose an electro-sensitive traffic light using the smart agent algorithm to reduce traffic congestion and traffic accidents. The multi-agent system approach can provide a new and preferable solution. The proposed method adaptively controls the cycle of traffic signals even though the traffic volume varies. Consequently, we reduce the car waiting time and start-up delay time using fuzzy control of feedback data. In particular, we have designed and implemented a system to...

  20. Interaction of Airspace Partitions and Traffic Flow Management Delay

    Science.gov (United States)

    Palopo, Kee; Chatterji, Gano B.; Lee, Hak-Tae

    2010-01-01

    To ensure that air traffic demand does not exceed airport and airspace capacities, traffic management restrictions, such as delaying aircraft on the ground, assigning them different routes and metering them in the airspace, are implemented. To reduce the delays resulting from these restrictions, revising the partitioning of airspace has been proposed to distribute capacity to yield a more efficient airspace configuration. The capacity of an airspace partition, commonly referred to as a sector, is limited by the number of flights that an air traffic controller can safely manage within the sector. Where viable, re-partitioning of the airspace distributes the flights over more efficient sectors and reduces individual sector demand. This increases the overall airspace efficiency, but requires additional resources in some sectors in terms of controllers and equipment, which is undesirable. This study examines the tradeoff of the number of sectors designed for a specified amount of traffic in a clear-weather day and the delays needed for accommodating the traffic demand. Results show that most of the delays are caused by airport arrival and departure capacity constraints. Some delays caused by airspace capacity constraints can be eliminated by re-partitioning the airspace. Analyses show that about 360 high-altitude sectors, which are approximately today s operational number of sectors of 373, are adequate for delays to be driven solely by airport capacity constraints for the current daily air traffic demand. For a marginal increase of 15 seconds of average delay, the number of sectors can be reduced to 283. In addition, simulations of traffic growths of 15% and 20% with forecasted airport capacities in the years 2018 and 2025 show that delays will continue to be governed by airport capacities. In clear-weather days, for small increases in traffic demand, increasing sector capacities will have almost no effect on delays.

  1. RFI channels

    Science.gov (United States)

    Mceliece, R. J.

    1980-01-01

    A class of channel models is presented which exhibit varying burst error severity much like channels encountered in practice. An information-theoretic analysis of these channel models is made, and conclusions are drawn that may aid in the design of coded communication systems for realistic noisy channels.

  2. Urban Traffic Control Using Adjusted Reinforcement Learning in a Multi-agent System

    Directory of Open Access Journals (Sweden)

    Mahshid Helali Moghadam

    2013-09-01

    Full Text Available Dynamism, continuous changes of states and the necessity to respond quickly are the specific characteristics of the environment in a traffic control system. Proposing an appropriate and flexible strategy to meet the existing requirements is always an important issue in traffic control. This study presents an adaptive approach to control urban traffic using multi-agent systems and a reinforcement learning augmented by an adjusting pre-learning stage. In this approach, the agent primarily uses some statistical traffic data and then uses traffic engineering theories for computing appropriate values of the traffic parameters. Having these primary values, the agents start the reinforcement learning based on the basic calculated information. The proposed approach, at first finds the approximate optimal zone for traffic parameters based on traffic engineering theories. Then using an appropriate reinforcement learning, it tries to exploit the best point according to different conditions. This approach was implemented on a network in traffic simulator software. The network was composed of six four phased intersections and 17 two lane streets. In the simulation, pedestrians were not considered in the system. The load of the network is defined in terms of Origin-Destination matrices whose entries represent the number of trips from an origin to a destination as a function of time. The simulation ran for five hours and an average traffic volume was used. According to the simulation results, the proposed approach behaved adaptively in different conditions and had better performance than the theory-based fixed-time control.

  3. A Multi-Operator Simulation for Investigation of Distributed Air Traffic Management Concepts

    Science.gov (United States)

    Peters, Mark E.; Ballin, Mark G.; Sakosky, John S.

    2002-01-01

    This paper discusses the current development of an air traffic operations simulation that supports feasibility research for advanced air traffic management concepts. The Air Traffic Operations Simulation (ATOS) supports the research of future concepts that provide a much greater role for the flight crew in traffic management decision-making. ATOS provides representations of the future communications, navigation, and surveillance (CNS) infrastructure, a future flight deck systems architecture, and advanced crew interfaces. ATOS also provides a platform for the development of advanced flight guidance and decision support systems that may be required for autonomous operations.

  4. TRAFFIC SIGNALS MODELLING WITH LONG DISTANCE COMMUNICATIONS USING PIC MICROCONTROLLER

    Directory of Open Access Journals (Sweden)

    Ahmet ÖZEK

    2004-04-01

    Full Text Available Today, microcontrollers are widely used in control and automation systems. For the automation of traffic signalization, the crossroads need to be controlled by microcontrollers and for the automation of more than one crossroad the communication of more than one microcontroller is required. In some special cases, the intercommunication of microcontrollers is required to change crossroad status and obtain continuous flow (green weave synchronization. In this study, a method is proposed to control the traffic flow on a hospital road with two crossroads located several km. apart from each other. For the purpose of changing the crossroads status to have a continuous flow of the traffic, the series of PIC16F877 microcontroller is used.

  5. DTALite: A queue-based mesoscopic traffic simulator for fast model evaluation and calibration

    Directory of Open Access Journals (Sweden)

    Xuesong Zhou

    2014-12-01

    Full Text Available A number of emerging dynamic traffic analysis applications, such as regional or statewide traffic assignment, require a theoretically rigorous and computationally efficient model to describe the propagation and dissipation of system congestion with bottleneck capacity constraints. An open-source light-weight dynamic traffic assignment (DTA package, namely DTALite, has been developed to allow a rapid utilization of advanced dynamic traffic analysis capabilities. This paper describes its three major modeling components: (1 a light-weight dynamic network loading simulator that embeds Newell’s simplified kinematic wave model; (2 a mesoscopic agent-based DTA procedure to incorporate driver’s heterogeneity; and (3 an integrated traffic assignment and origin–destination demand calibration system that can iteratively adjust path flow volume and distribution to match the observed traffic counts. A number of real-world test cases are described to demonstrate the effectiveness and performance of the proposed models under different network and data availability conditions.

  6. Air traffic generation for new terminal area air traffic management concepts design and evaluation

    OpenAIRE

    Besada Portas, Juan Alberto; Marquinez Prado, Iñigo; Portillo Garcia, Javier Ignacio; Miguel Vela, Gonzalo de; Bernardos Barbolla, Ana M.

    2015-01-01

    This paper describes two systems that can be used to obtain realistic random traffic samples in a terminal area: a real traffic analyser and a synthetic traffic generator. These two systems allow the air traffic management (ATM) engineer to gain insight on the traffic structure of the area under analysis, and allow obtaining realistic traffic samples enabling the evaluation of new operational concepts, the validation or system performance measurement after procedure changes, the analysis of A...

  7. A traffic situation analysis system

    Science.gov (United States)

    Sidla, Oliver; Rosner, Marcin

    2011-01-01

    The observation and monitoring of traffic with smart visions systems for the purpose of improving traffic safety has a big potential. For example embedded vision systems built into vehicles can be used as early warning systems, or stationary camera systems can modify the switching frequency of signals at intersections. Today the automated analysis of traffic situations is still in its infancy - the patterns of vehicle motion and pedestrian flow in an urban environment are too complex to be fully understood by a vision system. We present steps towards such a traffic monitoring system which is designed to detect potentially dangerous traffic situations, especially incidents in which the interaction of pedestrians and vehicles might develop into safety critical encounters. The proposed system is field-tested at a real pedestrian crossing in the City of Vienna for the duration of one year. It consists of a cluster of 3 smart cameras, each of which is built from a very compact PC hardware system in an outdoor capable housing. Two cameras run vehicle detection software including license plate detection and recognition, one camera runs a complex pedestrian detection and tracking module based on the HOG detection principle. As a supplement, all 3 cameras use additional optical flow computation in a low-resolution video stream in order to estimate the motion path and speed of objects. This work describes the foundation for all 3 different object detection modalities (pedestrians, vehi1cles, license plates), and explains the system setup and its design.

  8. Traffic noise in Hyderabad city. part I: road traffic noise

    International Nuclear Information System (INIS)

    Traffic noise survey was conducted at 20 sites in different areas and localities in Hyderabad city and each site noise data was collected continuously from 0800 to 2000 h. The data was analyzed for L/sub A99/, L/sub A90/, L/sub A50/, L/sub 10/ and L/sub A1/, and approximate values of L/sub Aeq12h/ were evaluated for each site. The results are discussed with reference to some criteria for community annoyance and means and ways to limit high-level traffic noise are suggested. (author)

  9. Percolation properties in a traffic model

    CERN Document Server

    Wang, Feilong; Xu, Xiaoyun; Wu, Ruoqian; Havlin, Shlomo

    2015-01-01

    As a dynamical complex system, traffic is characterized by a transition from free flow to congestions, which is mostly studied in highways. However, despite its importance in developing congestion mitigation strategies, the understanding of this common traffic phenomenon in a city-scale is still missing. An open question is how the traffic in the network collapses from a global efficient traffic to isolated local flows in small clusters, i.e. the question of traffic percolation. Here we study the traffic percolation properties on a lattice by simulation of an agent-based model for traffic. A critical traffic volume in this model distinguishes the free-state from congested state of traffic. Our results show that the threshold of traffic percolation decreases with increasing traffic volume and reaches a minimum value at the critical traffic volume. We show that this minimal threshold is the result of longest spatial correlation between traffic flows at the critical traffic volume. These findings may help to dev...

  10. Percolation properties in a traffic model

    Science.gov (United States)

    Wang, Feilong; Li, Daqing; Xu, Xiaoyun; Wu, Ruoqian; Havlin, Shlomo

    2015-11-01

    As a dynamical complex system, traffic is characterized by a transition from free flow to congestions, which is mostly studied in highways. However, despite its importance in developing congestion mitigation strategies, the understanding of this common traffic phenomenon in a city scale is still missing. An open question is how the traffic in the network collapses from a global efficient traffic to isolated local flows in small clusters, i.e. the question of traffic percolation. Here we study the traffic percolation properties on a lattice by simulation of an agent-based model for traffic. A critical traffic volume in this model distinguishes the free state from the congested state of traffic. Our results show that the threshold of traffic percolation decreases with increasing traffic volume and reaches a minimum value at the critical traffic volume. We show that this minimal threshold is the result of longest spatial correlation between traffic flows at the critical traffic volume. These findings may help to develop congestion mitigation strategies in a network view.

  11. Traffic Impact Simulation for Road Construction Project

    Directory of Open Access Journals (Sweden)

    Yazao Yang

    2012-12-01

    Full Text Available With the increasing traffic contradiction between supply and demand, urban traffic problems have become quite complex. Reasons for traffic congestion have become much more diverse. During the construction of urban road project, the surrounding road network will encounter a huge impact, traffic problems therefore emerged. Simulation is an important means for transport impact assessment, which has an important role for construction traffic impact analysis. Accordingly, traffic simulation is particularly important for policy setting and traffic organization. Taking an improvement project of Changjiang rapid road in Zhongshan city for example, this paper used the professional simulation software Vissim to analysis the impact of Qiwan road during the construction project. The simulation and traffic evaluation results can give some forward-looking and targeted measures about traffic safety, traffic organization, road facilities alteration and so on. The traffic impact analysis results shown that traffic safety and high-efficiency transport system must protected by good traffic re-organization projects and the simulation method is an effective mean to actualize traffic impact assessment.

  12. Functional Apical Large Conductance, Ca2+-activated, and Voltage-dependent K+ Channels Are Required for Maintenance of Airway Surface Liquid Volume*

    OpenAIRE

    Manzanares, Dahis; Gonzalez, Carlos; Ivonnet, Pedro; Chen, Ren-Shiang; Valencia-Gattas, Monica; Gregory E. Conner; Larsson, H. Peter; Salathe, Matthias

    2011-01-01

    Large conductance, Ca2+-activated, and voltage-dependent K+ (BK) channels control a variety of physiological processes in nervous, muscular, and renal epithelial tissues. In bronchial airway epithelia, extracellular ATP-mediated, apical increases in intracellular Ca2+ are important signals for ion movement through the apical membrane and regulation of water secretion. Although other, mainly basolaterally expressed K+ channels are recognized as modulators of ion transport in airway epithelial ...

  13. Boosting of synaptic potentials and spine Ca transients by the peptide toxin SNX-482 requires alpha-1E-encoded voltage-gated Ca channels.

    Directory of Open Access Journals (Sweden)

    Andrew J Giessel

    Full Text Available The majority of glutamatergic synapses formed onto principal neurons of the mammalian central nervous system are associated with dendritic spines. Spines are tiny protuberances that house the proteins that mediate the response of the postsynaptic cell to the presynaptic release of glutamate. Postsynaptic signals are regulated by an ion channel signaling cascade that is active in individual dendritic spines and involves voltage-gated calcium (Ca channels, small conductance (SK-type Ca-activated potassium channels, and NMDA-type glutamate receptors. Pharmacological studies using the toxin SNX-482 indicated that the voltage-gated Ca channels that signal within spines to open SK channels belong to the class Ca(V2.3, which is encoded by the Alpha-1E pore-forming subunit. In order to specifically test this conclusion, we examined the effects of SNX-482 on synaptic signals in acute hippocampal slices from knock-out mice lacking the Alpha-1E gene. We find that in these mice, application of SNX-482 has no effect on glutamate-uncaging evoked synaptic potentials and Ca influx, indicating that that SNX-482 indeed acts via the Alpha-1E-encoded Ca(V2.3 channel.

  14. Distributed Air Traffic Control Simulator

    Directory of Open Access Journals (Sweden)

    R. Radovanović

    2013-06-01

    Full Text Available During initial training air traffic control students acquire theoretical knowledge in various fields including air traffic management, aircraft performance, air traffic control equipment and systems, navigation and others. This paper proposes a simulator and explains its use and features that allows students to gain a practical insight into their coursework in order to complement their training. The goal of the simulator is to realistically implement all the key functionalities needed to cover the topics that were presented in class. The simulator offers a user friendly, distributed, and multi-role environment that can be deployed on regular PCs. Moreover, this paper discusses and resolves some of the main conceptual and implementational issues that were faced during simulator development.

  15. On vehicular traffic data analysis

    Energy Technology Data Exchange (ETDEWEB)

    Brics, Martins; Mahnke, Reinhard [Institute of Physics, Rostock University (Germany)

    2011-07-01

    This contribution consists of analysis of empirical vehicular traffic flow data. The main focus lies on the Next Generation Simulation (NGSIM) data. The first findings show that there are artificial structures within the data due to errors of monitoring as well as smoothing position measurement data. As a result speed data show discretisation in 5 feet per second. The aim of this investigation is to construct microscopic traffic flow models which are in agreement to the analysed empirical data. The ongoing work follows the subject of research summarized by Christof Liebe in his PhD thesis entitled ''Physics of traffic flow: Empirical data and dynamical models'' (Rostock, 2010).

  16. Traffic Signal Using Smart Agent System

    Directory of Open Access Journals (Sweden)

    Cheonshik Kim

    2008-01-01

    Full Text Available In this research, we propose an electro-sensitive traffic light using the smart agent algorithm to reduce traffic congestion and traffic accidents. The multi-agent system approach can provide a new and preferable solution. The proposed method adaptively controls the cycle of traffic signals even though the traffic volume varies. Consequently, we reduce the car waiting time and start-up delay time using fuzzy control of feedback data. In particular, we have designed and implemented a system to create optimum traffic signals in congested conditions. The effectiveness of this method was shown through simulation of multiple intersections.

  17. Structure Model of Urban Traffic System Evolution

    Institute of Scientific and Technical Information of China (English)

    JIANG Ke-jin; ZHANG Dian-ye

    2008-01-01

    A structure model of urban traffic system evolution is built based on the analysis of the factors influencing the system evolution and the hierarchy between the factors. Then the influencing degrees of the factors are quantificationally analyzed by DEMATE (decision making trial and evaluation laboratory). The analysis results indicate that the traffic mode structure which achieves the highest central degree is the dominant influencing factor of the urban traffic system evolution, and that economy development and the traffic poficy axe the second important factors that also affect the traffic mode structures. Furthermore, physical geography is a basic restriction to the urban traffic system evolution.

  18. Traffic and Granular Flow '11

    CERN Document Server

    Buslaev, Alexander; Bugaev, Alexander; Yashina, Marina; Schadschneider, Andreas; Schreckenberg, Michael; TGF11

    2013-01-01

    This book continues the biannual series of conference proceedings, which has become a classical reference resource in traffic and granular research alike. It addresses new developments at the interface between physics, engineering and computational science. Complex systems, where many simple agents, be they vehicles or particles, give rise to surprising and fascinating phenomena.   The contributions collected in these proceedings cover several research fields, all of which deal with transport. Topics include highway, pedestrian and internet traffic, granular matter, biological transport, transport networks, data acquisition, data analysis and technological applications. Different perspectives, i.e. modeling, simulations, experiments and phenomenological observations, are considered.

  19. Traffic Flow Management and Optimization

    Science.gov (United States)

    Rios, Joseph Lucio

    2014-01-01

    This talk will present an overview of Traffic Flow Management (TFM) research at NASA Ames Research Center. Dr. Rios will focus on his work developing a large-scale, parallel approach to solving traffic flow management problems in the national airspace. In support of this talk, Dr. Rios will provide some background on operational aspects of TFM as well a discussion of some of the tools needed to perform such work including a high-fidelity airspace simulator. Current, on-going research related to TFM data services in the national airspace system and general aviation will also be presented.

  20. Traffic forecasts ignoring induced demand

    DEFF Research Database (Denmark)

    Næss, Petter; Nicolaisen, Morten Skou; Strand, Arvid

    2012-01-01

    assessments of environmental impacts as well as the economic viability of proposed road projects, especially in situations where there is a latent demand for more road capacity. This has been illustrated in the present paper by an assessment of travel time savings, environmental impacts and the economic...... model calculations included only a part of the induced traffic, the difference in cost-benefit results compared to the model excluding all induced traffic was substantial. The results show lower travel time savings, more adverse environmental impacts and a considerably lower benefitcost ratio when...... ways of dealing with congestion and environmental problems in urban areas....

  1. TRAFFIC RETIMING SYSTEM USING IMAGE PROCESSING

    Directory of Open Access Journals (Sweden)

    Tanmayi Jain*

    2015-07-01

    Full Text Available One of the main problems in cities is traffic, this paper proposed new solution to traffic control. The main design concept of this project is to control the traffic automatically. System is made more efficient with addition of intelligence in term of artificial vision, using image processing techniques to estimate actual road traffic and compute time, each time for every road before enabling the signal. This model is resemblance of traditional traffic police man who takes better decision every time and soothes traffic flow. Unpredicted growth of traffic today has created serious problem in metro cities. This project has been implemented in the Matlab software and it aims to prevent heavy traffic in highways. Moreover, for implementing this project following steps must be considered: 1 image acquisition 2 RGB to gray scale transformation 3 image cropping and 4 density estimation. At first, film of highway is captured by a camera which is installed at the square that is intersection of road. Then, the camera takes pictures at regular intervals and then the captured frame is sent to the computer for further processing. After that, the number of cars in square is specified. At the end, if the number of cars is more than a threshold, a message is shown to inform the traffic status. By this message we can predict the need to reduce the size of traffic carried. Experiments show that the algorithm will work properly and also we can re-time the traffic green light and maintain the proper traffic management. Most of the city traffic is controlled by sensors and cameras shall be installed in big highways and streets. But existence of a system for detecting the size of traffic automatically will be felt. Such systems can allow extracting information from the bigger traffic issue and helps us decide to improve the traffic policy. The project aims to render automate control system for traffic on highways and street.

  2. Dynamic Density: An Air Traffic Management Metric

    Science.gov (United States)

    Laudeman, I. V.; Shelden, S. G.; Branstrom, R.; Brasil, C. L.

    1998-01-01

    The definition of a metric of air traffic controller workload based on air traffic characteristics is essential to the development of both air traffic management automation and air traffic procedures. Dynamic density is a proposed concept for a metric that includes both traffic density (a count of aircraft in a volume of airspace) and traffic complexity (a measure of the complexity of the air traffic in a volume of airspace). It was hypothesized that a metric that includes terms that capture air traffic complexity will be a better measure of air traffic controller workload than current measures based only on traffic density. A weighted linear dynamic density function was developed and validated operationally. The proposed dynamic density function includes a traffic density term and eight traffic complexity terms. A unit-weighted dynamic density function was able to account for an average of 22% of the variance in observed controller activity not accounted for by traffic density alone. A comparative analysis of unit weights, subjective weights, and regression weights for the terms in the dynamic density equation was conducted. The best predictor of controller activity was the dynamic density equation with regression-weighted complexity terms.

  3. Spatial regression analysis of traffic crashes in Seoul.

    Science.gov (United States)

    Rhee, Kyoung-Ah; Kim, Joon-Ki; Lee, Young-Ihn; Ulfarsson, Gudmundur F

    2016-06-01

    Traffic crashes can be spatially correlated events and the analysis of the distribution of traffic crash frequency requires evaluation of parameters that reflect spatial properties and correlation. Typically this spatial aspect of crash data is not used in everyday practice by planning agencies and this contributes to a gap between research and practice. A database of traffic crashes in Seoul, Korea, in 2010 was developed at the traffic analysis zone (TAZ) level with a number of GIS developed spatial variables. Practical spatial models using available software were estimated. The spatial error model was determined to be better than the spatial lag model and an ordinary least squares baseline regression. A geographically weighted regression model provided useful insights about localization of effects. The results found that an increased length of roads with speed limit below 30km/h and a higher ratio of residents below age of 15 were correlated with lower traffic crash frequency, while a higher ratio of residents who moved to the TAZ, more vehicle-kilometers traveled, and a greater number of access points with speed limit difference between side roads and mainline above 30km/h all increased the number of traffic crashes. This suggests, for example, that better control or design for merging lower speed roads with higher speed roads is important. A key result is that the length of bus-only center lanes had the largest effect on increasing traffic crashes. This is important as bus-only center lanes with bus stop islands have been increasingly used to improve transit times. Hence the potential negative safety impacts of such systems need to be studied further and mitigated through improved design of pedestrian access to center bus stop islands. PMID:26994374

  4. 77 FR 39927 - Vehicles and Traffic Safety-Bicycles

    Science.gov (United States)

    2012-07-06

    ... bicycle operator subject to most of the other traffic regulations in Part 4. 52 FR 10675, April 2, 1987... Responses to Public Comments The NPS published the proposed rule at 73 FR 76987 (December 18, 2008) and a... the special regulation requirement to ensure maximum public input on decisions to allow bicycle use...

  5. Trunk Reservation in Multi-service Networks with BPP Traffic

    DEFF Research Database (Denmark)

    Zheng, H.; Zhang, Qi; Iversen, Villy Bæk

    algorithm which allows for calculation of individual performance measures for each service, in particular the traffic congestion. The algorithm is numerically robust and requires a minimum of computer memory and computing time. The approximation is good when the services have equal mean service times....

  6. On the ground truth problem of malicious DNS traffic analysis

    DEFF Research Database (Denmark)

    Stevanovic, Matija; Pedersen, Jens Myrup; D’Alconzo, Alessandro;

    2015-01-01

    algorithms at their core. These methods require accurate ground truth of both malicious and benign DNS traffic for model training as well as for the performance evaluation. This paper elaborates on the problem of obtaining such a ground truth and evaluates practices employed by contemporary detection methods...

  7. BLIND CHANNEL ESTIMATION IN DELAY DIVERSITY FOR FREQUENCY SELECTIVE CHANNELS

    Institute of Scientific and Technical Information of China (English)

    Zhao Zheng; Jia Ying; Yin Qinye

    2003-01-01

    Delay diversity is an effective transmit diversity technique to combat adverse ef-fects of fading. Thus far, previous work in delay diversity assumed that perfect estimates ofcurrent channel fading conditions are available at the receiver and training symbols are requiredto estimate the channel from the transmitter to the receiver. However, increasing the number ofthe antennas increases the required training interval and reduces the available time within whichdata may be transmitted. Learning the channel coefficients becomes increasingly difficult for thefrequency selective channels. In this paper, with the subspace method and the delay character ofdelay diversity, a channel estimation method is proposed, which does not use training symbols. Itaddresses the transmit diversity for a frequency selective channel from a single carrier perspectivein the form of a simple equivalent fiat fading model. Monte Carlo simulations give the perfor-mance of channel estimation and the performance comparison of our channel-estimation-baseddetector with decision feedback equalization, which uses the perfect channel information.

  8. Trunk Reservation in Multi-service Networks with BPP Traffic

    DEFF Research Database (Denmark)

    Zheng, H.; Zhang, Qi; Iversen, Villy Bæk

    2006-01-01

    In this paper we develop approximate models for trunk reservation in multi-service systems with BPP (Binomial-Poisson-Pascal) multi-rate traffic streams. The approximation is a generalization of previous work by Tran-Gia & Hubner who assumed Poisson arrival processes. It is based on a generalized...... algorithm which allows for calculation of individual performance measures for each service, in particular the traffic congestion. The algorithm is numerically robust and requires a minimum of computer memory and computing time. The approximation is good when the services have equal mean service times....

  9. Highway and traffic engineering in developing countries

    DEFF Research Database (Denmark)

    1996-01-01

    Describes road and traffic engineering methods and problems in developing countries as opposed to similar problems in industrialized countries......Describes road and traffic engineering methods and problems in developing countries as opposed to similar problems in industrialized countries...

  10. A Multipath Connection Model for Traffic Matrices

    Directory of Open Access Journals (Sweden)

    Mr. M. V. Prabhakaran

    2015-02-01

    Full Text Available Peer-to-Peer (P2P applications have witnessed an increasing popularity in recent years, which brings new challenges to network management and traffic engineering (TE. As basic input information, P2P traffic matrices are of significant importance for TE. Because of the excessively high cost of direct measurement. In this paper,A multipath connection model for traffic matrices in operational networks. Media files can share the peer to peer, the localization ratio of peer to peer traffic. This evaluates its performance using traffic traces collected from both the real peer to peer video-on-demand and file-sharing applications. The estimation of the general traffic matrices (TM then used for sending the media file without traffic. Share the media file, source to destination traffic is not occur. So it give high performance and short time process.

  11. Wireless traffic steering for green cellular networks

    CERN Document Server

    Zhang, Shan; Zhou, Sheng; Niu, Zhisheng; Shen, Xuemin (Sherman)

    2016-01-01

    This book introduces wireless traffic steering as a paradigm to realize green communication in multi-tier heterogeneous cellular networks. By matching network resources and dynamic mobile traffic demand, traffic steering helps to reduce on-grid power consumption with on-demand services provided. This book reviews existing solutions from the perspectives of energy consumption reduction and renewable energy harvesting. Specifically, it explains how traffic steering can improve energy efficiency through intelligent traffic-resource matching. Several promising traffic steering approaches for dynamic network planning and renewable energy demand-supply balancing are discussed. This book presents an energy-aware traffic steering method for networks with energy harvesting, which optimizes the traffic allocated to each cell based on the renewable energy status. Renewable energy demand-supply balancing is a key factor in energy dynamics, aimed at enhancing renewable energy sustainability to reduce on-grid energy consum...

  12. IMPROVING VEHICLE FLOW WITH TRAFFIC LIGHTS

    OpenAIRE

    J. POLI; L. H. A. Monteiro

    2005-01-01

    A probabilistic cellular automata is used for investigating how a traffic light placed on a street intersection influences vehicle velocities. Numerical simulations reveal that above a critical density of cars, the traffic light improves the flow in both directions.

  13. Agent Base Network Traffic Monitoring

    Directory of Open Access Journals (Sweden)

    MONIKA JOSHI, CHIRAG GOHEL

    2013-05-01

    Full Text Available Raspberry Pi the credit-card-sized single board computer device which adopts a high performance embedded microprocessor and an embedded real-time Linux operating system, which hangs the characteristics of miniaturization, digitalization and network together well. It has virtues of low cost, small volume and flexible networking, etc, because of embedded technology adoption. Network administrators need to see what’s going on with their network. They need to know what the traffic on their network is comprised of, who's using the bandwidth, and how their infrastructure is handling the load. Fortunately, Linux runs a wide variety of free, open source network monitoring and traffic analysis applications that can give net administrator this type of insight. So this paper focuses on how to deploy network monitoring tool within this device which monitors the network traffic within LAN using the tool ntop. Ntop is a simple, free, portable traffic measurement and monitoring tool, which supports various management activities, including network optimization and to plan, and detection of network security violations.

  14. Traffic Congestion and Congestion Pricing

    OpenAIRE

    Lindsey, C. Robin; Verhoef, Erik T.

    2000-01-01

    For several decades growth of traffic volumes has outstrippedinvestments inroad infrastructure. The result has been a relentless increase intrafficcongestion. This paper reviews the economic principles behindcongestionpricing in static and dynamic settings, which derive from thebenefits ofcharging travellers for the externalities they create. Specialattention ispaid to various complications that make simple textbook congestionpricingmodels of limited relevance, and dictate that congestion pri...

  15. Traffic accident with radioactive material

    International Nuclear Information System (INIS)

    A traffic accident with a package with radioactive contents of the category 'III-YELLOW' remaining undamaged, caused complete confusion among the responsible rescue services. All forces active until professional fire-brigades arrived showed a deficit of tactical radiation protection behaviour. Even a medical unit with an equipped emergency task force in situ and radiation protection equipment did not feel responsible. (DG)

  16. Future Emissions from Railway Traffic

    DEFF Research Database (Denmark)

    Sorenson, Spencer C.

    1998-01-01

    In investigation of the expected development in factors which influence railway energy consumption and emissions. Traffic factors such as train speed, load, an occupancy were considered. Tehcnical factors such an emissions factors, fleet composition and train weight were also considered. An...

  17. Traffic at risk in Mediterranean

    International Nuclear Information System (INIS)

    The Mediterranean Sea represents only about 0.7% of the planet's total water surface area, yet it is host to as much as one-quarter of the world's total maritime oil traffic. Statistics indicate that from 47 to 77,000 tonnes of crude oil are now being released annually into the Sea through accidental spills; and over the last decade, its tourism dependent coastlines have been fouled by the highest levels of tar contamination in the world. Oil carrier traffic, routed within the Sea's already overcrowded shipping lanes, is intense and this traffic is expected to increase, as a result of rises in world energy demand, to levels of from 7 to 8 million barrels a day. It has been estimated that, at the end of 1992, 90% of all large tankers operating in this area, will have reached a service life of 15-16 years which is very close to the average recommended life cycle limit of 15-20 years. Only 20% of the world's 3,000 tankers are currently equipped with double bottomed hulls. This paper uses these and other facts and figures to argue that the risks of future severe oil tanker accidents in the Mediterranean Sea are high, and that these must be countered with the development of a new set of stricter marine traffic safety regulations at the Italian, national, as well as, European level

  18. Cubesat Constellation Design for Air Traffic Monitoring

    Science.gov (United States)

    Nag, Sreeja; Rios, Joseph Lucio; Gerhardt, David; Pham, Camvu

    2015-01-01

    Suitably equipped global and local air traffic can be tracked. The tracking information may then be used for control from ground-based stations by receiving the Automatic Dependent Surveillance-Broadcast (ADS-B) signal. The ADS-B signal, emitted from the aircraft's Mode-S transponder, is currently tracked by terrestrial based receivers but not over remote oceans or sparsely populated regions such as Alaska or the Pacific Ocean. Lack of real-time aircraft time/location information in remote areas significantly hinders optimal planning and control because bigger "safety bubbles" (lateral and vertical separation) are required around the aircraft until they reach radar-controlled airspace. Moreover, it presents a search-and-rescue bottleneck. Aircraft in distress, e.g. Air France AF449 that crashed in 2009, take days to be located or cannot be located at all, e.g. Malaysia Airlines MH370 in 2014. In this paper, we describe a tool for designing a constellation of small satellites which demonstrates, through high-fidelity modeling based on simulated air traffic data, the value of space-based ADS-B monitoring and provides recommendations for cost-efficient deployment of a constellation of small satellites to increase safety and situational awareness in the currently poorly-served surveillance area of Alaska. Air traffic data has been obtained from the Future ATM Concepts Evaluation Tool (FACET), developed at NASA Ames Research Center, simulated over the Alaskan airspace over a period of one day. The simulation is driven by MATLAB with satellites propagated and coverage calculated using AGI's Satellite ToolKit(STK10).

  19. Improving Experience-Based Admission Control through Traffic Type Awareness

    Directory of Open Access Journals (Sweden)

    Jens Milbrandt

    2007-04-01

    Full Text Available Experience-based admission control (EBAC is a hybrid approach combining the classical parameter-based and measurement-based admission control. EBAC calculates an appropriate overbooking factor used to overbook link capacities with resource reservations in packet-switched networks. This overbooking factor correlates with the average peak-to-mean rate ratio of all admitted traffic flows on the link. So far, a single overbooking factor is calculated for the entire traffic aggregate. In this paper, we propose typespecific EBAC which provides a compound overbooking factor considering different types of traffic that subsume flows with similar peak-to-mean rate ratios. The concept can be well implemented since it does not require measurements of type-specific traffic aggregates. We give a proof of concept for this extension and compare it with the conventional EBAC approach. We show that EBAC with type-specific overbooking leads to better resource utilization under normal conditions and to faster response times for changing traffic mixes.

  20. Simulation of Road Traffic Applying Model-Driven Engineering

    Directory of Open Access Journals (Sweden)

    Alberto FERNÁNDEZ-ISABEL

    2016-05-01

    Full Text Available Road traffic is an important phenomenon in modern societies. The study of its different aspects in the multiple scenarios where it happens is relevant for a huge number of problems. At the same time, its scale and complexity make it hard to study. Traffic simulations can alleviate these difficulties, simplifying the scenarios to consider and controlling their variables. However, their development also presents difficulties. The main ones come from the need to integrate the way of working of researchers and developers from multiple fields. Model-Driven Engineering (MDE addresses these problems using Modelling Languages (MLs and semi-automatic transformations to organise and describe the development, from requirements to code. This paper presents a domain-specific MDE framework for simulations of road traffic. It comprises an extensible ML, support tools, and development guidelines. The ML adopts an agent-based approach, which is focused on the roles of individuals in road traffic and their decision-making. A case study shows the process to model a traffic theory with the ML, and how to specialise that specification for an existing target platform and its simulations. The results are the basis for comparison with related work.

  1. Traffic Signals in Motorcycle Dependent Cities

    OpenAIRE

    Do, Quoc Cuong

    2009-01-01

    Traffic signal control was first invented in 1868 in Great Britain. Then, it has quickly spread across many other countries, what are now usually developed countries. Therefore, during a long history of development, traffic signals usually have been dealing with traffic in which four-wheel vehicles play an important role in motorised traffic. However, as a result of an unequal development among countries, many Motorcycle Dependent Cities (MDCs) nowadays still exist mostly in the developing co...

  2. Traffic Engineering And Supporting QoS

    OpenAIRE

    2003-01-01

    ABSTRACT Traffic Engineering describes techniques for optimising network performance by measuring, modelling, characterizing and controlling Internet traffic for specific performance goals [11]. This is a comprehensive definition. Traffic engineering performance goals typically fall into one of two categories. The first one is traffic related performance objectives such as minimizing packet loss, lowering end-to-end delay, or supporting a contracted Service Level Agreement (SLA). The se...

  3. Protection Methods in Traffic Engineering MPLS Networks

    OpenAIRE

    Kimani, Peter

    2013-01-01

    The objective of this project was to perform a theoretical review of Multiprotocol Label Switching (MPLS) Traffic Engineering (TE) technology and traffic protection methods in the Traffic Engineering on MPLS networks and implement traffic protection in an ISP’s (Internet Service Provider’s) network. The project was carried out first by introducing VPN (Virtual Private Network) and its different categories and modes. VPN is closely related to MPLS. The MPLS-TE was introduced and its operat...

  4. Vehicle Traffic Congestion Estimation Based on RFID

    OpenAIRE

    Al-Naima, Fawzi M.; Hamd, Hassan A.

    2012-01-01

    Due to the proliferation in the number of vehicles on the road, traffic problems are bound to exist. Therefore, the use of Intelligent Transportation Systems (ITS) has become mandatory for obtaining traffic information from roads. Radio Frequency Identification (RFID) technology has been used to obtain vehicles’ IDs (tag ID) from RFID readers and to collect traffic information in real‐time. This paper proposes a simulation system for the Vehicle Traffic Congestion Estimation (VTCE) based on R...

  5. Traffic Monitoring Using M2M Communication

    OpenAIRE

    Kumar, Shiu; Ham, Eun Sik; Lee, Seong Ro

    2014-01-01

    This paper presents an intelligent traffic monitoring system using wireless vision sensor network that captures and processes the real-time video image to obtain the traffic flow rate and vehicle speeds along different urban roadways. This system will display the traffic states on the front roadways that can guide the drivers to select the right way and avoid potential traffic congestions. On the other hand, it will also monitor the vehicle speeds and store the vehicle details, for those brea...

  6. Particle hopping models and traffic flow theory

    OpenAIRE

    Nagel, Kai

    1995-01-01

    This paper shows how particle hopping models fit into the context of traffic flow theory. Connections between fluid-dynamical traffic flow models, which derive from the Navier-Stokes-equations, and particle hopping models are shown. In some cases, these connections are exact and have long been established, but have never been viewed in the context of traffic theory. In other cases, critical behavior of traffic jam clusters can be compared to instabilities in the partial differential equations...

  7. Empirical Phase Diagram of Congested Traffic Flow

    OpenAIRE

    Lee, H. Y.; Lee, H. -W.; Kim, D.

    1999-01-01

    We present an empirical phase diagram of the congested traffic flow measured on a highway section with one effective on-ramp. Through the analysis of local density-flow relations and global spatial structure of the congested region, four distinct congested traffic states are identified. These states appear at different levels of the upstream flux and the on-ramp flux, thereby generating a phase digram of the congested traffic flow. Observed traffic states are discussed in connection with rece...

  8. Traffic incidents analysis on Slovenian motorway network

    OpenAIRE

    Jakše, Bojan

    2013-01-01

    In my bachelor thesis we were analysing traffic incidents (such as accidents, congestions, heavy snow, etc.) on Slovenian road network, specifically we focused on incidents on motorways. We were starting from database of incidents provided by Prometno-informacijski center (Traffic information center) and added information about hourly traffic at the moment of incident. We were also researching possible correlations between weather and traffic congestions and accidents as well as behaviour of ...

  9. Analysis of urban traffic patterns using clustering

    OpenAIRE

    Weijermars, Wilhelmina Adriana Maria

    2007-01-01

    Mobility is still increasing, as are its corresponding negative side effects such as congestion and air pollution. To be able to take adequate measures to minimize these side effects, it is important to obtain insight into the functioning of the traffic system. In common practice, the traffic analysis process deals with average traffic volumes. However, also the variability of traffic volumes is of crucial importance, for example with regard to travel time reliability, the robustness of the r...

  10. Revolutionizing Technology Prioritizing Emergency Vehicles in Traffic

    OpenAIRE

    B. Ramya Sundaram; E. Aravind; S. Harithaa; G. Karthick; Shriram K. Vasudevan

    2014-01-01

    The following study brings to the fore a technology exclusively engineered to eradicate the snags and inadequacies persisting in the existing system of traffic control and thus aims to provide a sophisticated operation and uninterrupted course for the emergency vehicles. The traffic in Indian roads has shown a tremendous rise over the years and the conventional pre-timed traffic signals and frequent traffic congestions, delaying the road commuters, have led to outrage and chaos on several occ...

  11. Economic Traffic Management: Mechanisms and Applications

    OpenAIRE

    Hecht, Fabio V; Stiller, Burkhard

    2012-01-01

    The paradigm shift from centralized services into hundreds of thousands of decentralized services changes traffic directions and patterns in the Internet. In that light, overlay providers form logical communication topologies, which effect the underlying telcos’ as well as Internet Service Providers’ (ISP) traffic and network management. Thus, Economic Traffic Management (ETM) principles deal with incentives, decentralized traffic generation, and modern applications, such as integrated Video-...

  12. WIRELESS COMMUNICATION IN COOPERATIVE URBAN TRAFFIC MANAGEMENT

    OpenAIRE

    Vujić, Miroslav; Škorput, Pero; Ćelić, Jasmin

    2015-01-01

    The possibility to enable cooperative concept in urban traffic systems is challenging because of large amount of traffic data that must be collected, processed and distributed to end users. The main objective is to establish communication between three main subsystems of traffic system: driver, vehicle and infrastructure so that they can cooperate in real time traffic environment. This paper describes various wireless communication technologies that can be used to achieve real time dana excha...

  13. Approaches for Intelligent Traffic System: A Survey

    OpenAIRE

    Pratishtha Gupta; G. N. Purohit; Amrita Dadhich

    2012-01-01

    This survey presents various approaches for intelligent traffic systems. The potential research fields in which Intelligent Traffic System emerges as an important application area are highlighted andvarious issues have been identified which need to be handled while developing such a system for an urban area, where an efficient traffic management has become the need of hour.A model is also proposed capable of managing intelligent traffic system using CCTV cameras and WAN. The proposed model wi...

  14. Physics of traffic gridlock in a city

    OpenAIRE

    Kerner, Boris S.

    2011-01-01

    Based of simulations of a stochastic three-phase traffic flow model, we reveal that at a signalized city intersection under small link inflow rates at which a vehicle queue developed during the red phase of light signal dissolves fully during the green phase, i.e., no traffic gridlock should be expected, nevertheless, traffic breakdown with the subsequent city gridlock occurs with some probability after a random time delay. This traffic breakdown is initiated by a first-order phase transition...

  15. TRAFFIC SENSITIVE AND TRAFFIC LOAD AWARE PATH SELECTION ALGORITHM FOR MMR WIMAX NETWORKS

    Directory of Open Access Journals (Sweden)

    Sandhya Kulkarni

    2011-08-01

    Full Text Available The recent developments in the broadband wireless access (BWA communication systems haveintroduced several major changes to the existing systems. Legacy IEEE 802.16j is one such amendment tothe existing IEEE 802.16 WiMAX family. The key modification introduced by 802.16j system is theconcept of relay station (RS, which may be used to enhance the system coverage or to make systemthroughput optimal. The end terminals, subscriber stations (SS are unchanged in the standard. Theoverall change pertinent to the system has raised many unresolved issues related to RS and multi-hoprelay base station (MR-BS. The selection of path from a SS to MR-BS via a RS is also one of the issues,need to be addressed. The path selection of a SS in both uplink and downlink directions is left open in thestandard. It is very significant to satisfy the traffics of stringent quality of service (QoS requirements andto appropriately manage the resources of a cell under different circumstances. This paper proposes apath selection algorithm to achieve the aforementioned qualities in the network. The path selectionmetrics include traffic load of the transparent relay station and traffic sensitivity factor of the SS. Anextensive simulation work discusses the performance evaluation of the proposed work using QualNetsimulator.

  16. Road Traffic Accidents in Kazakhstan

    Directory of Open Access Journals (Sweden)

    Alma Aubakirova

    2013-03-01

    Full Text Available Background: The article provides the analysis of death rates in road traffic accidents in Kazakhstan from 2004 to 2010 and explores the use of sanitary aviation.Methods: Data of fatalities caused by road traffic accidents were collected and analysed. Descriptive and analytical methods of epidemiology and biomedical statistics were applied.Results: Totaly 27,003 people died as a result of road traffic accidents in this period. The death rate for the total population due to road traffic accidents was 25.0±2.10/0000. The death rate for men was (38.3±3.20/0000, which was higher (P<0.05 than that for women (12.6±1.10/0000. High death rates in the entire male population were identified among men of 30-39 years old, whereas the highest rates for women were attributed to the groups of 50-59 years old and 70-79 years old. In time dynamics, death rates tended to decrease: the total population (Тdec=−2.4%, men (Тdec=−2.3% and women (Тdec=−1.4%. When researching territorial relevance, the rates were established as low (to 18.30/0000, average (between18.3 and24.00/0000 and high (from 24.00/0000 and above. Thus, the regions with high rates included Akmola region (24.30/0000, Mangistau region (25.90/0000, Zhambyl region (27.30/0000, Almaty region (29.30/0000 and South Kazakhstan region (32.40/0000.Conclusion: The identified epidemiological characteristics of the population deaths rates from road traffic accidents should be used in integrated and targeted interventions to enhance prevention of injuries in accidents.

  17. Traffic fatalities and economic growth.

    Science.gov (United States)

    Kopits, Elizabeth; Cropper, Maureen

    2005-01-01

    This paper examines the relationship between traffic fatality risk and per capita income and uses it to forecast traffic fatalities by geographic region. Equations for the road death rate (fatalities/population) and its components--the rate of motorization (vehicles/population) and fatalities per vehicle (F/V)--are estimated using panel data from 1963 to 1999 for 88 countries. The natural logarithm of F/P, V/P, and F/V are expressed as spline (piecewise linear) functions of the logarithm of real per capita GDP (measured in 1985 international prices). Region-specific time trends during the period 1963-1999 are modeled in linear and log-linear form. These models are used to project traffic fatalities and the stock of motor vehicles to 2020. The per capita income at which traffic fatality risk (fatalities/population) begins to decline is 8600 US dollars (1985 international dollars) when separate time trends are used for each geographic region. This turning point is driven by the rate of decline in fatalities/vehicles as income rises since vehicles/population, while increasing with income at a decreasing rate, never declines with economic growth. Projections of future traffic fatalities suggest that the global road death toll will grow by approximately 66% over the next twenty years. This number, however, reflects divergent rates of change in different parts of the world: a decline in fatalities in high-income countries of approximately 28% versus an increase in fatalities of almost 92% in China and 147% in India. The road death rate is projected to rise to approximately 2 per 10,000 persons in developing countries by 2020, while it will fall to less than 1 per 10,000 in high-income countries. PMID:15607288

  18. 49 CFR 1139.2 - Traffic study.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 8 2010-10-01 2010-10-01 false Traffic study. 1139.2 Section 1139.2... of General Commodities § 1139.2 Traffic study. (a) The respondents shall submit a traffic study for... “base-calendar year—actual.” The study shall include a probability sampling of the actual...

  19. Predicting Information Flows in Network Traffic.

    Science.gov (United States)

    Hinich, Melvin J.; Molyneux, Robert E.

    2003-01-01

    Discusses information flow in networks and predicting network traffic and describes a study that uses time series analysis on a day's worth of Internet log data. Examines nonlinearity and traffic invariants, and suggests that prediction of network traffic may not be possible with current techniques. (Author/LRW)

  20. Empirical analysis of heterogeneous traffic flow

    NARCIS (Netherlands)

    Ambarwati, L.; Pel, A.J.; Verhaeghe, R.J.; Van Arem, B.

    2013-01-01

    Traffic flow in many developing countries is strongly mixed comprising vehicle types, such as motorcycles, cars, (mini) buses, and trucks; furthermore, traffic flow typically exhibits free inter-lane exchanges. This phenomenon causes a complex vehicle interaction, rendering most existing traffic flo

  1. Traffic Flow Models and Their Numerical Solutions

    OpenAIRE

    Jin, Wenlong

    2004-01-01

    In this thesis, Riemann problems and Godunov methods are developed for higher order traffic flow models. A rigorous analysis of the first order traffic flow model of inhomogeneous road is presented. A two-level simulation framework of network vehicular traffic is proposed as a Godunov-type finite difference system with the supply-demand method as an alternative of Riemann solver.

  2. 30 CFR 56.9100 - Traffic control.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Traffic control. 56.9100 Section 56.9100 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Dumping Traffic Safety § 56.9100 Traffic control. To provide for the safe movement of...

  3. NEW POSSIBILITIES OF RAILWAY TRAFFIC CONTROL SYSTEMS

    Directory of Open Access Journals (Sweden)

    Lionginas LIUDVINAVIČIUS

    2016-06-01

    Full Text Available This article analyses the train traffic control systems in 1435 mm and 1520 mm gauge railways. The article analyses the aspects of train traffic control and locomotive energy saving by using the coordinates of track profile change that have been received from GPS. In the article, achievements of Lithuanian railways (LG in the area of train traffic control optimisation are presented.

  4. NEW POSSIBILITIES OF RAILWAY TRAFFIC CONTROL SYSTEMS

    OpenAIRE

    Lionginas LIUDVINAVIČIUS; Stasys DAILYDKA; Aleksander SŁADKOWSKI

    2016-01-01

    This article analyses the train traffic control systems in 1435 mm and 1520 mm gauge railways. The article analyses the aspects of train traffic control and locomotive energy saving by using the coordinates of track profile change that have been received from GPS. In the article, achievements of Lithuanian railways (LG) in the area of train traffic control optimisation are presented.

  5. Computational intelligence for traffic and mobility

    CERN Document Server

    Wang, Wuhong

    2012-01-01

    This book presents the new development of computation intelligence for traffic, transportation and mobility, the main contents include traffic safety, mobility analysis, intelligent transportation system, smart vehicle, transportation behavior, driver modeling and assistance, transportation risk analysis and reliability system analysis, vehicle operation and active safety, urban traffic management and planning.

  6. 30 CFR 57.9100 - Traffic control.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Traffic control. 57.9100 Section 57.9100 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE... Dumping Traffic Safety § 57.9100 Traffic control. To provide for the safe movement of...

  7. Prediction of Railway Passenger Traffic Volume

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The current situation of the railway passenger traffic (RPT) andthe traffic marketing is analyzed. The grey model theory is adopted to establish a prediction model for the railway passenger traffic volume (RPTV). The RPTV from 2001 to 2005 is predicted with the proposed model, and a few suggestions are put forward.

  8. A traffic model of optical networks based on time-space complexity and traffic grooming

    Institute of Scientific and Technical Information of China (English)

    Zhao Yongli; Zhang Jie; Han Dahai; Wang Lei; Chen Xiuzhong; Gu Wanyi

    2009-01-01

    This paper researched the traffic of optical networks in time-space complexity, proposed a novel traffic model for complex optical networks based on traffic grooming, designed a traffic generator GTS (generator based on time and space) with "centralized + distributed" idea, and then made a simulation in C language. Experiments results show that GTS can produce the virtual network topology which can change dynamically with the characteristic of scaling-free network. GTS can also groom the different traffic and trigger them under real-time or scheduling mechanisms, generating different optical connections. This traffic model is convenient for the simulation of optical networks considering the traffic complexity.

  9. Aberrant over-expression of TRPM7 ion channels in pancreatic cancer: required for cancer cell invasion and implicated in tumor growth and metastasis

    Directory of Open Access Journals (Sweden)

    Nelson S. Yee

    2015-03-01

    Full Text Available Our previous studies in zebrafish development have led to identification of the novel roles of the transient receptor potential melastatin-subfamily member 7 (TRPM7 ion channels in human pancreatic cancer. However, the biological significance of TRPM7 channels in pancreatic neoplasms was mostly unexplored. In this study, we determined the expression levels of TRPM7 in pancreatic tissue microarrays and correlated these measurements in pancreatic adenocarcinoma with the clinicopathological features. We also investigated the role of TRPM7 channels in pancreatic cancer cell invasion using the MatrigelTM-coated transwell assay. In normal pancreas, TRPM7 is expressed at a discernable level in the ductal cells and centroacinar cells and at a relatively high level in the islet endocrine cells. In chronic pancreatitis, pre-malignant tissues, and malignant neoplasms, there is variable expression of TRPM7. In the majority of pancreatic adenocarcinoma specimens examined, TRPM7 is expressed at either moderate-level or high-level. Anti-TRPM7 immunoreactivity in pancreatic adenocarcinoma significantly correlates with the size and stages of tumors. In human pancreatic adenocarcinoma cells in which TRPM7 is highly expressed, short hairpin RNA-mediated suppression of TRPM7 impairs cell invasion. The results demonstrate that TRPM7 channels are over-expressed in a proportion of the pre-malignant lesions and malignant tumors of the pancreas, and they are necessary for invasion by pancreatic cancer cells. We propose that TRPM7 channels play important roles in development and progression of pancreatic neoplasm, and they may be explored as clinical biomarkers and targets for its prevention and treatment.

  10. Robustness and computational efficiency of a Kalman Filter estimator of time-dependent origin-destination matrices: exploiting ICT traffic measurements from information and communications technologiess

    OpenAIRE

    Barceló Bugeda, Jaime; Montero Mercadé, Lídia; Bullejos González, Manuel Antonio; Linares Herreros, Mª Paz; Serch Muni, Oriol

    2013-01-01

    Origin–destination (O-D) trip matrices that describe the patterns of traffic behavior across a network are the primary data input used in principal traffic models and, therefore, a critical requirement in all advanced systems supported by dynamic traffic assignment models. However, because O-D matrices are not directly observable, the current practice consists of adjusting an initial or seed matrix from link flow counts that are provided by an existing layout of traffic-counting stations. The...

  11. Traffic Control in ATM Networks : Engineering Impacts of Realistic Traffic Processes

    OpenAIRE

    Jena, Ajit K.; Popescu, Adrian; Pruthi, Parag; Erramilli, Ashok

    1996-01-01

    This paper reviews the current state of the art in the rapidly developing areas of ATM traffic controls and traffic modeling, and identifies future research areas to facilitate the implementation of control methods that can support a desired quality of service without sacrificing network utilizations. Two sets of issues are identified, one on the impacts of realistic traffic on the efficacy of traffic controls in supporting specific traffic management objectives, and the other dealing with th...

  12. Modeling and Simulation of a Traffic Flow Model Considering the Influence of Traffic Interruption

    OpenAIRE

    Yang, Shu-hong; Li, Chui-Gui; Xia, Dong-Xue; Wang, Meng; Wang, Xiao-Rong

    2013-01-01

    In this paper, we present a new lattice model of traffic flow by considering the effects of traffic interruption probability. The stability condition of the proposed model is obtained by employing the linear stability theory. The results show that the stability of traffic flow is improved by considering the influence of traffic interruption. Applying the method of nonlinear analysis, the modified Korteweg-de Vries (mKdV) equation is derived to describe the traffic behavior near the critical p...

  13. Traffic Flow Prediction Using MI Algorithm and Considering Noisy and Data Loss Conditions: An Application to Minnesota Traffic Flow Prediction

    OpenAIRE

    Hosseini, Seyed Hadi; Moshiri, Behzad; Rahimi-Kian, Ashkan; Nadjar Araabi, Babak

    2014-01-01

    Traffic flow forecasting is useful for controlling traffic flow, traffic lights, and travel times. This study uses a multi-layer perceptron neural network and the mutual information (MI) technique to forecast traffic flow and compares the prediction results with conventional traffic flow forecasting methods. The MI method is used to calculate the interdependency of historical traffic data and future traffic flow. In numerical case studies, the proposed traffic flow forecasting method was test...

  14. Temporal Characteristics of Large IP Traffic Flows

    OpenAIRE

    Abrahamsson, Henrik; Ahlgren, Bengt

    2003-01-01

    Several studies of Internet traffic have shown that it is a small percentage of the flows that dominate the traffic. This is often referred to as the mice and elephants phenomenon. It has been proposed that this might be one of very few invariants of Internet traffic and that this property could somehow be used for traffic engineering purposes. The idea being that one in a scalable way could control a major part of the traffic by only keeping track of a small number of flows. But for this the...

  15. Characterization and Modeling of Network Traffic

    DEFF Research Database (Denmark)

    Shawky, Ahmed; Bergheim, Hans; Ragnarsson, Olafur;

    2011-01-01

    This paper attempts to characterize and model backbone network traffic, using a small number of statistics. In order to reduce cost and processing power associated with traffic analysis. The parameters affecting the behaviour of network traffic are investigated and the choice is that inter......-arrival time, IP addresses, port numbers and transport protocol are the only necessary parameters to model network traffic behaviour. In order to recreate this behaviour, a complex model is needed which is able to recreate traffic behaviour based on a set of statistics calculated from the parameters values...

  16. Fuzzy Multiobjective Traffic Light Signal Optimization

    OpenAIRE

    N. Shahsavari Pour; H. Asadi; M. Pour Kheradmand

    2013-01-01

    Traffic congestion is a major concern for many cities throughout the world. In a general traffic light controller, the traffic lights change at a constant cycle time. Hence it does not provide an optimal solution. Many traffic light controllers in current use are based on the “time-of-the-day” scheme, which use a limited number of predetermined traffic light patterns and implement these patterns depending upon the time of the day. These automated systems do not provide an optimal control for ...

  17. TRAFFIC SIGNALS MODELLING WITH LONG DISTANCE COMMUNICATIONS USING PIC MICROCONTROLLER

    OpenAIRE

    ÖZEK, Ahmet; Karal, Ömer

    2004-01-01

    Today, microcontrollers are widely used in control and automation systems. For the automation of traffic signalization, the crossroads need to be controlled by microcontrollers and for the automation of more than one crossroad the communication of more than one microcontroller is required. In some special cases, the intercommunication of microcontrollers is required to change crossroad status and obtain continuous flow (green weave) synchronization. In this study, a method is proposed to cont...

  18. NEW SYSTEM OF PREPARING THE PERSONNEL OF THE RAIL-FREIGHT TRAFFIC IN MODERN CONDITION

    OpenAIRE

    Koroleva, N.

    2009-01-01

    The Considered problem of preparing the personnel in modern condition. The main requirements is Determined to new system of preparing the personnel in condition innovations developments of the rail-freight traffic.

  19. Dense Urban Channel Measurements for Utility Pole Fixed Wireless Links

    OpenAIRE

    Wasson, Michael W.; Messier, Geoffrey G.; Smith, Devin P.

    2016-01-01

    This radio channel measurement campaign characterizes the propagation conditions experienced in a dense urban environment over fixed backhaul links between wireless devices that are mounted on utility or traffic light poles. The measurements characterize the 2x1 multiple input single output channel in the 2.45 GHz band for both spatially separated omni antennas and cross polarized directional antennas. Results presented include both small and large scale channel statistics, antenna correlatio...

  20. Models, methods and software tools for building complex adaptive traffic systems

    International Nuclear Information System (INIS)

    The paper studies the modern methods and tools to simulate the behavior of complex adaptive systems (CAS), the existing systems of traffic modeling in simulators and their characteristics; proposes requirements for assessing the suitability of the system to simulate the CAS behavior in simulators. The author has developed a model of adaptive agent representation and its functioning environment to meet certain requirements set above, and has presented methods of agents' interactions and methods of conflict resolution in simulated traffic situations. A simulation system realizing computer modeling for simulating the behavior of CAS in traffic situations has been created

  1. The car following model considering traffic jerk

    Science.gov (United States)

    Ge, Hong-Xia; Zheng, Peng-jun; Wang, Wei; Cheng, Rong-Jun

    2015-09-01

    Based on optimal velocity car following model, a new model considering traffic jerk is proposed to describe the jamming transition in traffic flow on a highway. Traffic jerk means the sudden braking and acceleration of vehicles, which has a significant impact on traffic movement. The nature of the model is researched by using linear and nonlinear analysis method. A thermodynamic theory is formulated to describe the phase transition and critical phenomenon in traffic flow. The time-dependent Ginzburg-Landau (TDGL) equation and the modified Korteweg-de Vries (mKdV) equation are derived to describe the traffic flow near the critical point and the traffic jam. In addition, the connection between the TDGL and the mKdV equations are also given.

  2. Agent Based Individual Traffic guidance

    DEFF Research Database (Denmark)

    Wanscher, Jørgen Bundgaard

    2004-01-01

    vehicle can be obtained through cellular phone tracking or GPS systems. This information can then be used to provide individual traffic guidance as opposed to the mass information systems of today -- dynamic roadsigns and trafficradio. The goal is to achieve better usage of road and time. The main topic......When working with traffic planning or guidance it is common practice to view the vehicles as a combined mass. >From this models are employed to specify the vehicle supply and demand for each region. As the models are complex and the calculations are equally demanding the regions and the detail of...... the road network is aggregated. As a result the calculations reveal only what the mass of vehicles are doing and not what a single vehicle is doing. This is the crucial difference to ABIT (Agent Based Individual Trafficguidance). ABIT is based on the fact that information on the destination of each...

  3. Energy consumption in rail traffic

    International Nuclear Information System (INIS)

    This report for the Swiss Federal Office of Energy (SFOE) presents the first results of a short study made on the energy consumption of the Swiss rail-bound systems for the transport of persons and goods. In this initial short study, data collected on the electricity and fossil fuel consumption of the Swiss Federal Railways and further railway companies in Switzerland is presented. The consumption is split into various categories such as person and goods traffic, internal traffic, building-infrastructure (stations, workshops, tunnels etc.) and equipment (signals, point-heaters, lighting, safety equipment). Data is presented in tables and in graphical form in relation to person-kilometres and tonne-kilometres. The development of consumption over a period of years is discussed and comparisons are made with figures for the German rail system

  4. Stochastic stability of traffic maps

    International Nuclear Information System (INIS)

    We study the ergodic properties of a family of traffic maps acting in the space of bi-infinite sequences of real numbers. The corresponding dynamics mimics the motion of vehicles in a simple traffic flow, which explains the name. Using connections to topological Markov chains we obtain nontrivial invariant measures, prove their stochastic stability and calculate the topological entropy. Technically these results in the deterministic setting are related to the construction of measures of maximal entropy via measures uniformly distributed on periodic points of a given period, while in the random setting we construct (spatially) Markov invariant measures directly. In distinction to conventional results the limiting measures in the non-lattice case are non-ergodic. The average velocity of individual ‘vehicles’ as a function of their density and its stochastic stability is studied as well. (paper)

  5. Modelling traffic pollution in streets

    Energy Technology Data Exchange (ETDEWEB)

    Berkowicz, R.; Hertel, O. [National Environmental Research Inst., Dept. of Atmospheric Environment, Roskilde (Denmark); Larsen, S.E.; Soerensen, N.N.; Nielsen, M. [Risoe National Lab., Dept. of Meteorology and Wind Energy, Roskilde (Denmark)

    1997-01-01

    This report concerns mainly the subject related to modelling air pollution from traffic in urban streets. A short overview is presented over the theoretical aspects and examples of most commonly used methods and models are given. Flow and dispersion conditions in street canyons are discussed and the presentation is substantiated with the analysis of the experimental data. The main emphasis is on the modelling methods that are suitable for routine applications and a more detailed presentation is given of the Operational Street Pollution Model (OSPM), which was developed by the National Environmental Research Institute. The model is used for surveillance of air pollution from traffic in Danish cities and also for special air pollution studies. (au) 76 refs.

  6. Automated Negotiation for Traffic Regulation

    OpenAIRE

    Gaciarz, Matthis; Aknine, Samir; BHOURI, Neila

    2015-01-01

    Urban congestion is a major problem in our society for quality of life and for productivity. The increasing communication abilities of vehicles and recent advances in artificial intelligence allow new solutions to be considered for traffic regulation, based on real-time information and distributed cooperative decision-making models. The paper presents a mechanism allowing a distributed regulation of the right-of-way of the vehicles at an intersection. The decision-making relies on an automati...

  7. Real Time Network Traffic Monitoring

    OpenAIRE

    Tripp, Gerald

    1999-01-01

    This paper looks at the problems of real time network traffic monitoring. Some of the existing approaches are reviewed, looking at both simple filtering systems and also systems based on the use of finite state machines that can report specific events or capture data only when in particular states. Finally, some existing implementation techniques are examined and an outline proposal made for the design of a network monitoring system that uses finite state machines implemented using associativ...

  8. Software for Simulating Air Traffic

    Science.gov (United States)

    Sridhar, Banavar; Bilimoria, Karl; Grabbe, Shon; Chatterji, Gano; Sheth, Kapil; Mulfinger, Daniel

    2006-01-01

    Future Air Traffic Management Concepts Evaluation Tool (FACET) is a system of software for performing computational simulations for evaluating advanced concepts of advanced air-traffic management. FACET includes a program that generates a graphical user interface plus programs and databases that implement computational models of weather, airspace, airports, navigation aids, aircraft performance, and aircraft trajectories. Examples of concepts studied by use of FACET include aircraft self-separation for free flight; prediction of air-traffic-controller workload; decision support for direct routing; integration of spacecraft-launch operations into the U.S. national airspace system; and traffic- flow-management using rerouting, metering, and ground delays. Aircraft can be modeled as flying along either flight-plan routes or great-circle routes as they climb, cruise, and descend according to their individual performance models. The FACET software is modular and is written in the Java and C programming languages. The architecture of FACET strikes a balance between flexibility and fidelity; as a consequence, FACET can be used to model systemwide airspace operations over the contiguous U.S., involving as many as 10,000 aircraft, all on a single desktop or laptop computer running any of a variety of operating systems. Two notable applications of FACET include: (1) reroute conformance monitoring algorithms that have been implemented in one of the Federal Aviation Administration s nationally deployed, real-time, operational systems; and (2) the licensing and integration of FACET with the commercially available Flight Explorer, which is an Internet- based, real-time flight-tracking system.

  9. Economic analysis of traffic safety

    OpenAIRE

    Delhaye, Eef

    2007-01-01

    In this dissertation I focus on the behaviour of people – and more particularly on the choice of speed/level of care and the number of trips they make - as 85 percent of all accidents are mainly due to road users’ error. This behaviour can be influenced by the use of different instruments such as traffic regulation, liability rules, infrastructural and technical measures, education and sensitisation. The focus of this work lies on regulation and its enforcement, liability rules and economic i...

  10. Probabilistic Description of Traffic Breakdowns

    OpenAIRE

    Kuhne, Reinhart; Mahnke, Reinhard; Lubashevsky, Ihor; Kaupuzs, Jevgenijs

    2001-01-01

    We analyze the characteristic features of traffic breakdown. To describe this phenomenon we apply to the probabilistic model regarding the jam emergence as the formation of a large car cluster on highway. In these terms the breakdown occurs through the formation of a certain critical nucleus in the metastable vehicle flow, which enables us to confine ourselves to one cluster model. We assume that, first, the growth of the car cluster is governed by attachment of cars to the cluster whose rate...

  11. [Fitness to drive under traffic ophthalmological aspects in elderly drivers].

    Science.gov (United States)

    Schneebeli, Martina

    2016-01-01

    The Federal Roads Office (FEDRO), Switzerlands federal authority carries responsibility for the action program “Via Sicura” in order to reduce drastically the number of road traffic fatalities and serious injuries on Swiss roads. The revision of the VZV (Verkehrszulassungsverordnung) included in this program will come in to force on 1.July 2016. On that account the legal medical requirements for driver will be renewed. In particular, the requirements for vision (visual acuity, visual field) will be adjusted to international standards. Due to demographic changes the number of elderly drivers with old age (85 – 90+) with eye associated diseases increases. Therefore, questions concerning traffic ophthalmological problems have to be increasingly considered within traffic medical assessments. The driver's vision in traffic's safety must enable him to perceive relevant information, process information quickly and perform an adequate reaction in time, even if visibility is limited (e. g. due to rain, night, darkness) or in the presence of physical or psychical constraints. PMID:26982648

  12. Field Programmable Gate Array (FPGA Model of Intelligent Traffic Light System with Saving Power

    Directory of Open Access Journals (Sweden)

    Ali Hashim Jryian

    2012-01-01

    Full Text Available In this paper, a FPGA model of intelligent traffic light system with power saving was built. The intelligent traffic light system consists of sensors placed on the side's ends of the intersection to sense the presence or absence of vehicles. This system reduces the waiting time when the traffic light is red, through the transition from traffic light state to the other state, when the first state spends a lot of time, because there are no more vehicles. The proposed system is built using VHDL, simulated using Xilinx ISE 9.2i package, and implemented using Spartan-3A XC3S700A FPGA kit. Implementation and Simulation behavioral model results show that the proposed intelligent traffic light system model satisfies the specified operational requirements.

  13. Dynamic Channel Allocation in Sectored Cellular Systems

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    It is known that dynamic channel assignment(DCA) strategy outperforms the fixed channel assignment(FCA) strategy in omni-directional antenna cellular systems. One of the most important methods used in DCA was channel borrowing. But with the emergence of cell sectorization and spatial division multiple access(SDMA) which are used to increase the capacity of cellular systems, the channel assignment faces a series of new problems. In this paper, a dynamic channel allocation scheme based on sectored cellular systems is proposed. By introducing intra-cell channel borrowing (borrowing channels from neighboring sectors) and inter-cell channel borrowing (borrowing channels from neighboring cells) methods, previous DCA strategies, including compact pattern based channel borrowing(CPCB) and greedy based dynamic channel assignment(GDCA) schemes proposed by the author, are improved significantly. The computer simulation shows that either intra-cell borrowing scheme or inter-cell borrowing scheme is efficient enough to uniform and non-uniform traffic service distributions.

  14. Tailoring particle translocation via dielectrophoresis in pore channels.

    Science.gov (United States)

    Tanaka, Shoji; Tsutsui, Makusu; Theodore, Hu; Yuhui, He; Arima, Akihide; Tsuji, Tetsuro; Doi, Kentaro; Kawano, Satoyuki; Taniguchi, Masateru; Kawai, Tomoji

    2016-01-01

    Understanding and controlling electrophoretic motions of nanoscopic objects in fluidic channels are a central challenge in developing nanopore technology for molecular analyses. Although progress has been made in slowing the translocation velocity to meet the requirement for electrical detections of analytes via picoampere current measurements, there exists no method useful for regulating particle flows in the transverse directions. Here, we report the use of dielectrophoresis to manipulate the single-particle passage through a solid-state pore. We created a trap field by applying AC voltage between electrodes embedded in a low-aspect-ratio micropore. We demonstrated a traffic control of particles to go through center or near side surface via the voltage frequency. We also found enhanced capture efficiency along with faster escaping speed of particles by virtue of the AC-mediated electroosmosis. This method is compatible with nanopore sensing and would be widely applied for reducing off-axis effects to achieve single-molecule identification. PMID:27527126

  15. Decentralized and Tactical Air Traffic Flow Management

    Science.gov (United States)

    Bertsimas, Dimitris; Odoni, Amedeo R.

    1997-01-01

    This project dealt with the following topics: 1. Review and description of the existing air traffic flow management system (ATFM) and identification of aspects with potential for improvement. 2. Identification and review of existing models and simulations dealing with all system segments (enroute, terminal area, ground) 3. Formulation of concepts for overall decentralization of the ATFM system, ranging from moderate decentralization to full decentralization 4. Specification of the modifications to the ATFM system required to accommodate each of the alternative concepts. 5. Identification of issues that need to be addressed with regard to: determination of the way the ATFM system would be operating; types of flow management strategies that would be used; and estimation of the effectiveness of ATFM with regard to reducing delay and re-routing costs. 6. Concept evaluation through identification of criteria and methodologies for accommodating the interests of stakeholders and of approaches to optimization of operational procedures for all segments of the ATFM system.

  16. Transportation and General Traffic Management, Change 2

    Science.gov (United States)

    1979-01-01

    This Handbook sets forth those transportation and general traffic management responsibilities, guidelines, and procedures governing the use of commercial and Government transportation for NASA. Transportation is an integral function of the logistic process, involving all activities incident to the movement of persons and things. The fundamental and continuous objectives of transportation are to control and diminish the time-distance of lines of communication by the most suitable means. The function of transportation is accomplished through, and encompasses all, the planning, direction, supervision, and execution of the technical, operational, and administrative tasks required to procure or furnish efficient and economical conveyance of cargo and personnel by all modes of commercial and Government transportation. This Handbook is applicable to NASA Headquarters and Field Installations.

  17. Beating the traffic with commuting alternatives

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    This pamphlet describes how, by encouraging commuting options, local governments can help reduce air pollution, fuel consumption, and traffic congestion. Minimizing these problems makes the community more appealing to businesses, residents, and visitors and boosts the local economy. Approaches to alternative transportation are as varied as the communities devising and using them. But the critical factor is initiative from local governments, often one of communities largest employers. They can use and promote commuting alternatives among their employees. Local governments can also promote alternative transportation among other employers and the general public. They can provide information on commuting options, improve the infrastructure, and use local authority to require and reward those changes necessary to make alternative transportation a widely accepted part of community life. Best of all, local governments can lead by example and establish a template for other employers to follow.

  18. Intelligent Testing of Traffic Light Programs: Validation in Smart Mobility Scenarios

    Directory of Open Access Journals (Sweden)

    Javier Ferrer

    2016-01-01

    Full Text Available In smart cities, the use of intelligent automatic techniques to find efficient cycle programs of traffic lights is becoming an innovative front for traffic flow management. However, this automatic programming of traffic lights requires a validation process of the generated solutions, since they can affect the mobility (and security of millions of citizens. In this paper, we propose a validation strategy based on genetic algorithms and feature models for the automatic generation of different traffic scenarios checking the robustness of traffic light cycle programs. We have concentrated on an extensive urban area in the city of Malaga (in Spain, in which we validate a set of candidate cycle programs generated by means of four optimization algorithms: Particle Swarm Optimization for Traffic Lights, Differential Evolution for Traffic Lights, random search, and Sumo Cycle Program Generator. We can test the cycles of traffic lights considering the different states of the city, weather, congestion, driver expertise, vehicle’s features, and so forth, but prioritizing the most relevant scenarios among a large and varied set of them. The improvement achieved in solution quality is remarkable, especially for CO2 emissions, in which we have obtained a reduction of 126.99% compared with the experts’ solutions.

  19. Memory effects in quantum channel discrimination

    OpenAIRE

    Chiribella G.; D'Ariano G.M.; Perinotti P.

    2008-01-01

    We consider quantum-memory assisted protocols for discriminating quantum channels. We show that for optimal discrimination of memory channels, memory assisted protocols are needed. This leads to a new notion of distance for channels with memory. For optimal discrimination and estimation of sets of unitary channels memory-assisted protocols are not required.

  20. A Wideband Channel Model for Intravehicular Nomadic Systems

    Directory of Open Access Journals (Sweden)

    François Bellens

    2011-01-01

    Full Text Available The increase in electronic entertainment equipments within vehicles has rendered the idea of replacing the wired links with intra-vehicle personal area networks. Ultra-wideband (UWB seems an appropriate candidate technology to meet the required data rates for interconnecting such devices. In particular, the multiband OFDM (MB-OFDM is able to provide very high transfer rates (up to 480 MBps over relatively short distances and low transmit power. In order to evaluate the performances of UWB systems within vehicles, a reliable channel model is needed. In this paper, a nomadic system where a base station placed in the center of the dashboard wants to communicate with fixed devices placed at the rear seat is investigated. A single-input single-output (SISO channel model for intra-vehicular communication (IVC systems is proposed, based on reverberation chamber theory. The model is based on measurements conducted in real traffic conditions, with a varying number of passengers in the car. Temporal variations of the wireless channels are also characterized and parametrized. The proposed model is validated by comparing model-independent statistics with the measurements.

  1. Real time highway traffic prediction based on dynamic demand modeling

    OpenAIRE

    Bernhardsson, Viktor; Ringdahl, Rasmus

    2014-01-01

    Traffic problems caused by congestion are increasing in cities all over the world. As a traffic management tool traffic predictions can be used in order to make prevention actions against traffic congestion. There is one software for traffic state estimations called Mobile Millennium Stockholm (MMS) that are a part of a project for estimate real-time traffic information.In this thesis a framework for running traffic predictions in the MMS software have been implemented and tested on a stretch...

  2. Demand-oriented traffic management for incidents and disasters

    OpenAIRE

    Flötteröd, Yun-Pang; Bieker, Laura

    2012-01-01

    Traffic simulation has been extensively used as a decision support tool for efficient traffic management in daily life. During disasters and incidents, traffic simulation can further help rescue teams to understand the current traffic state and the possible impacts of proposed strategies and then to make proper decisions. At this point, the changes in traffic demand should also be considered in the simulation to reflect the latest traffic state. In this paper, a demand-oriented traffic manage...

  3. Image Processing Based Traffic Sign Recognising System

    Directory of Open Access Journals (Sweden)

    Neha M. Betgeri

    2013-11-01

    Full Text Available Road traffic signs provide important information for guiding, warning, or regulating the behaviors of driver in order to make driving safer and easier. Automatic recognition of traffic signs is important for an automated intelligent driving vehicle or for driver assistance systems. We have designed such a robust and a fault tolerant system so that it can be a part of the so called “Driver Support Systems”. This paper presents a study to recognize traffic sign patterns using Hough transform and slope detection method. Images are pre-processed with several image processing techniques, such as, boundary trace, edge detection, erosion etc. And then using slope detection technique, which is different and new approach than color based and shape based technique, respective traffic sign is detected. Which in turns give commands to wireless robot to move according to the detected traffic sign. (Here we are specifically considering traffic sign boards of arrow.

  4. Traffic Flow Management Wrap-Up

    Science.gov (United States)

    Grabbe, Shon

    2011-01-01

    Traffic Flow Management involves the scheduling and routing of air traffic subject to airport and airspace capacity constraints, and the efficient use of available airspace. Significant challenges in this area include: (1) weather integration and forecasting, (2) accounting for user preferences in the Traffic Flow Management decision making process, and (3) understanding and mitigating the environmental impacts of air traffic on the environment. To address these challenges, researchers in the Traffic Flow Management area are developing modeling, simulation and optimization techniques to route and schedule air traffic flights and flows while accommodating user preferences, accounting for system uncertainties and considering the environmental impacts of aviation. This presentation will highlight some of the major challenges facing researchers in this domain, while also showcasing recent innovations designed to address these challenges.

  5. Traffic and Granular Flow ’07

    CERN Document Server

    Chevoir, François; Gondret, Philippe; Lassarre, Sylvain; Lebacque, Jean-Patrick; Schreckenberg, Michael

    2009-01-01

    This book covers several research fields, all of which deal with transport. Three main topics are treated: road traffic, granular matter, and biological transport. Different points of view, i.e. modelling, simulations, experiments, and phenomenological observations, are considered. Sub-topics include: highway or urban vehicular traffic (dynamics of traffic, macro/micro modelling, measurements, data analysis, security issues, psychological issues), pedestrian traffic, animal traffic (e.g. social insects), collective motion in biological systems (molecular motors...), granular flow (dense flows, intermittent flows, solid/liquid transition, jamming, force networks, fluid and solid friction), networks (biological networks, urban traffic, the internet, vulnerability of networks, optimal transport networks) and cellular automata applied to the various aforementioned fields.

  6. Traffic Engineering With Traditional IP Routing Protocols

    OpenAIRE

    Fortz, Bernard; Rexford, Jennifer; Thorup, Mikkel

    2002-01-01

    Traffic engineering involves adapting the routing of traffic to the network conditions, with the joint goals of good user performance and efficient use of network resources. In this paper, we describe an approach to intradomain traffic engineering that works within the existing deployed base of Interior Gateway Protocols (IGPs), such as Open Shortest Path First (OSPF) and Intermediate System-Intermediate System (IS-IS). We explain how to adapt the configuration of link weights, based on a ...

  7. Deep Learning Predictors for Traffic Flows

    OpenAIRE

    Polson, Nicholas; Sokolov, Vadim

    2016-01-01

    We develop a deep learning predictor for modeling traffic flows. The challenge arises as traffic flows have sharp nonlinearities resulting from transitions from free flow to breakdown and then to congested flow. Our methodology uses a deep learning architecture to capture nonlinear spatio-temporal flow effects. We show how traffic flow data, from road sensors, can be predicted using deep learning. For comparison, we use a benchmark sparse $\\ell_1$ trend filter and we illustrate our methodolog...

  8. Traffic at the Edge of Chaos

    OpenAIRE

    K, Nagel; S, Rasmussen

    1995-01-01

    We use a very simple description of human driving behavior to simulate traffic. The regime of maximum vehicle flow in a closed system shows near-critical behavior, and as a result a sharp decrease of the predictability of travel time. Since Advanced Traffic Management Systems (ATMSs) tend to drive larger parts of the transportation system towards this regime of maximum flow, we argue that in consequence the traffic system as a whole will be driven closer to criticality, thus making prediction...

  9. Fractal Analysis On Internet Traffic Time Series

    CERN Document Server

    Chong, K B

    2002-01-01

    Fractal behavior and long-range dependence have been observed in tele-traffic measurement and characterization. In this paper we show results of application of the fractal analysis to internet traffic via various methods. Our result demonstrate that the internet traffic exhibits self-similarity. Time-scale analysis show to be an effective way to characterize the local irregularity. Based on the result of this study, these two Internet time series exhibit fractal characteristic with long-range dependence.

  10. Modelling and control of road traffic networks

    OpenAIRE

    Haut, Bertrand

    2007-01-01

    Road traffic networks offer a particularly challenging research subject to the control community. The traffic congestion around big cities is constantly increasing and is now becoming a major problem. However, the dynamics of a road network exhibit some complex behaviours such as nonlinearities, delays and saturation effects that prevent the use of some classical control algorithms. This thesis presents different models and control algorithms used for road traffic networks. The dynamics ar...

  11. Residential Exposure to Traffic and Spontaneous Abortion

    OpenAIRE

    Green, Rochelle S; Malig, Brian; Windham, Gayle C.; Fenster, Laura; Ostro, Bart; Swan, Shanna

    2009-01-01

    Background Studies have shown associations between air pollution or traffic exposure and adverse birth outcomes, such as low birth weight. However, very few studies have examined the effect of traffic emissions on spontaneous abortion (SAB). Objective The goal of this study was to determine whether residential exposure to vehicular traffic was associated with SAB. Methods Pregnant women from a prepaid health plan in California were recruited into a prospective cohort study in 1990–1991. Three...

  12. Traffic calming schemes : opportunities and implementation strategies.

    OpenAIRE

    Schagen, I.N.L.G. van (samenst.)

    2003-01-01

    Commissioned by the Swedish National Road Authority, this report aims to provide a concise overview of knowledge of and experiences with traffic calming schemes in urban areas, both on a technical level and on a policy level. Traffic calming refers to a combination of network planning and engineering measures to enhance road safety as well as other aspects of liveability for the citizens. More specifically, in the current report the starting point is that traffic calming schemes in residentia...

  13. LED Traffic Light as Communication Device

    OpenAIRE

    Kwan, TO; Chan, CH; Liu, HS; Pang, GKH

    1999-01-01

    The visible light from an LED (light emitting diode) traffic light can be modulated and encoded with information. Hence, it can be used for the broadcasting of audio messages or any traffic or road information. Essentially all LED traffic lights can be used as communications devices. The paper focuses on the description of an audio information system made up of high brightness, visible light emitting diodes (LEDs) in which one or more LEDs are modulated and encoded with audio messages. The sy...

  14. Queues in Series in Light Traffic

    OpenAIRE

    Blaszczyszyn, B.; Rolski, T.

    1993-01-01

    We study light traffic approximations for queues in series with renewal arrivals and i.i.d. service time vectors. Formulae for limits of functions of the waiting time at different stations based on single customer effect are obtained for two approaches: dilation and thinning of the arrival process. Interdeparture times from a station possess a one-dependence property in light traffic. This paper complements previous studies of Daley and Rolski and also Asmussen's approach to light traffic lim...

  15. Hazard based models for freeway traffic incident duration.

    Science.gov (United States)

    Tavassoli Hojati, Ahmad; Ferreira, Luis; Washington, Simon; Charles, Phil

    2013-03-01

    Assessing and prioritising cost-effective strategies to mitigate the impacts of traffic incidents and accidents on non-recurrent congestion on major roads represents a significant challenge for road network managers. This research examines the influence of numerous factors associated with incidents of various types on their duration. It presents a comprehensive traffic incident data mining and analysis by developing an incident duration model based on twelve months of incident data obtained from the Australian freeway network. Parametric accelerated failure time (AFT) survival models of incident duration were developed, including log-logistic, lognormal, and Weibul-considering both fixed and random parameters, as well as a Weibull model with gamma heterogeneity. The Weibull AFT models with random parameters were appropriate for modelling incident duration arising from crashes and hazards. A Weibull model with gamma heterogeneity was most suitable for modelling incident duration of stationary vehicles. Significant variables affecting incident duration include characteristics of the incidents (severity, type, towing requirements, etc.), and location, time of day, and traffic characteristics of the incident. Moreover, the findings reveal no significant effects of infrastructure and weather on incident duration. A significant and unique contribution of this paper is that the durations of each type of incident are uniquely different and respond to different factors. The results of this study are useful for traffic incident management agencies to implement strategies to reduce incident duration, leading to reduced congestion, secondary incidents, and the associated human and economic losses. PMID:23333698

  16. A Framework For Concept Drifting P2P Traffic Identification

    Directory of Open Access Journals (Sweden)

    Guanghui Yan

    2013-08-01

    Full Text Available Identification of network traffic using port-based or payload-based analysis is becoming increasing difficult with many Peer-to-Peer (P2P application using dynamic ports, masquerading techniques, and encryption to avoid detection. To overcome this problem, several machine learning technique were proposed to classify P2P traffics. But in the real P2P network environment, new communities of peers often attend and old communities of peers often leave. It requires the identification methods to be capable of coping with concept drift, and updating the model incrementally. In this paper, we present a concept-adapting algorithm CluMC which is based on streaming data mining techniques to identify P2P applications in Internet traffic. The CluMC use micro-cluster structures which contain potential micro-cluster structures and outlier micro-cluster structures to classify the P2P traffic and discover the concept drift with limited memory. Our performance study over a number of real data sets that we captured at a main gateway router demonstrates the effectiveness and efficiency of our method.

  17. Traffic Control System by Incorporating Message Forwarding Approach

    Directory of Open Access Journals (Sweden)

    K.V.Ramana, Raghu.B.Korrapati, N.Pattabhi Ram & K.Syam Kumari

    2011-11-01

    Full Text Available During the last few years, continuous progresses in wireless communications have opened new researchfields in computer networking, aimed at extending data networks connectivity to environments wherewired solutions are impracticable. Among these, vehicular traffic is attracting a growing attention fromboth academia and industry, due to the amount and importance of related distributive applications tomobile entertainment. VANETs are self-organized networks built up from moving vehicles, and are part ofthe broader class of MANETs. Because of these peculiar characteristics, VANETs require newnetworking techniques, whose feasibility and performance are usually tested by means of simulation. Inorder to meet performance goals, it is widely agreed that VANETs must rely heavily on node-to-nodecommunication. In VANET, each vehicle acts as a node and communicates with other vehicles within therange or communicates with base stations. The main idea is to deploy a wireless communication networkthat has a capability of sending and receiving messages between transmitter and mobile devices in theparticular network. Results can be shown using an effective VEINS Simulator. This Simulator canproduce detailed vehicular movement traces and can simulate different traffic conditions through fullycustomizable scenarios. The Framework is expected to be employed using such simulator that makesuse of traffic modulator, network simulator and coupling module that integrates the traffic and network.

  18. MCMC simulation of GARCH model to forecast network traffic load

    Directory of Open Access Journals (Sweden)

    Akhter Raza Syed

    2012-05-01

    Full Text Available The performance of a computer network can be enhanced by increasing number of servers, upgrading the hardware, and gaining additional bandwidth but this solution require the huge amount to invest. In contrast to increasing the bandwidth and hardware resources, network traffic modeling play a significant role in enhancing the network performance. As the emphasis of telecommunication service providers shifted towards the high-speed networks providing integrated services at a prescribed Quality of Service (QoS, the role of accurate traffic models in network design and network simulation becomes ever more crucial. We analyze a traffic volume time series of internet requests made to a workstation. This series exhibits a long-range dependence and self-similarity in large time scale and exhibits multifractal in small time scale. In this paper, for this time series, we proposed Generalized Autoregressive Conditional Heteroscedastic, (GARCH model, and practical techniques for model fitting, Markov Chain Monte Carlo simulation and forecasting issues are demonstrated. The proposed model provides us simple and accurate approach for simulating internet data traffic patterns.

  19. Traffic Control System by Incorporating Message Forwarding Approach

    Directory of Open Access Journals (Sweden)

    K.V.Ramana Ph.D

    2011-10-01

    Full Text Available During the last few years, continuous progresses in wireless communications have opened new research fields in computer networking, aimed at extending data networks connectivity to environments where wired solutions are impracticable. Among these, vehicular traffic is attracting a growing attention from both academia and industry, due to the amount and importance of related distributive applications to mobile entertainment. VANETs are self-organized networks built up from moving vehicles, and are part of the broader class of MANETs. Because of these peculiar characteristics, VANETs require new networking techniques, whose feasibility and performance are usually tested by means of simulation. In order to meet performance goals, it is widely agreed that VANETs must rely heavily on node-to-node communication. In VANET, each vehicle acts as a node and communicates with other vehicles within the range or communicates with base stations. The main idea is to deploy a wireless communication network that has a capability of sending and receiving messages between transmitter and mobile devices in the particular network. Results can be shown using an effective VEINS Simulator. This Simulator can produce detailed vehicular movement traces and can simulate different traffic conditions through fully customizable scenarios. The Framework is expected to be employed using such simulator that makes use of traffic modulator, network simulator and coupling module that integrates the traffic and network.

  20. Traffic flow optimization on roundabouts

    OpenAIRE

    Delle Monache, Maria Laura; Obsu, Legesse Lemecha; Goatin, Paola; Kassa, Semu Mitiku

    2013-01-01

    The aim of this paper is to optimize the traffic flow on roundabouts using a macroscopic approach. The roundabout is modeled as a sequence of 2x2 junctions: with one mainline and secondary incoming and outgoing roads. We consider two cost functionals: the total travel time and the total waiting time, which give an estimate of the time spent by drivers on the network section. These cost functionals are minimized analytically for each junction with respect to the right of way parameter of the i...

  1. TRAFFIC SURVEILLANCE VIDEO MANAGEMENT SYSTEM

    OpenAIRE

    Ganesan, K.; Kavitha C; Kriti Tandon; Lakshmipriya.R

    2010-01-01

    Now-a-days, the application of the lane surveillance system increases quickly, for example, it is widely settled at the entrance of highways and toll booths to strengthen the traffic management and survey the public security. Accordingly, the size of the captured video data increases over time. So, it is quite important to study how to manage this video data and how to extract useful information from this large amount of video data. In order to process huge volume of data efficiently in tr...

  2. A study into ward traffic

    Directory of Open Access Journals (Sweden)

    P. Hardcatle

    1982-09-01

    Full Text Available The study was undertaken in 1980 and was prompted by a need to highlight some of the problems associated with the ward milieu, both for patient care and for nurse teaching. Being associated at that time with the clinical teaching department the author was very interested in looking into the amount of traffic entering the ward area. It seemed that the ward sister had a very difficult task in providing a therapeutic environment for her patients, and that patient care was always being criticised with little thought to what was actually occurring in the ward.

  3. Multi-Layer Traffic Steering

    DEFF Research Database (Denmark)

    Fotiadis, Panagiotis; Polignano, Michele; Gimenez, Lucas Chavarria; Viering, Ingo; Sartori, Cinzia; Lobinger, Andreas; Pedersen, Klaus I.

    2013-01-01

    This paper investigates the potentials of traffic steering in the Radio Resource Control (RRC) Idle state by evaluating the Absolute Priorities (AP) framework in a multilayer Long Term Evolution (LTE) macrocell scenario. Frequency priorities are broadcast on the system information and RRC Idle...... signaling. The priority adjustment is based on both the Composite Available Capacity (CAC) and the radio conditions of the candidate layers. Compared to broadcast AP, the proposed scheme achieves better load balancing performance and improves network capacity, given that the User Equipment (UE) inactivity...

  4. Real-Time Corrected Traffic Correlation Model for Traffic Flow Forecasting

    Directory of Open Access Journals (Sweden)

    Hua-pu Lu

    2015-01-01

    Full Text Available This paper focuses on the problems of short-term traffic flow forecasting. The main goal is to put forward traffic correlation model and real-time correction algorithm for traffic flow forecasting. Traffic correlation model is established based on the temporal-spatial-historical correlation characteristic of traffic big data. In order to simplify the traffic correlation model, this paper presents correction coefficients optimization algorithm. Considering multistate characteristic of traffic big data, a dynamic part is added to traffic correlation model. Real-time correction algorithm based on Fuzzy Neural Network is presented to overcome the nonlinear mapping problems. A case study based on a real-world road network in Beijing, China, is implemented to test the efficiency and applicability of the proposed modeling methods.

  5. On the reproducibility of spatiotemporal traffic dynamics with microscopic traffic models

    CERN Document Server

    Knorr, Florian

    2012-01-01

    Traffic flow is a very prominent example of a driven non-equilibrium system. A characteristic phenomenon of traffic dynamics is the spontaneous and abrupt drop of the average velocity on a stretch of road leading to congestion. Such a traffic breakdown corresponds to a boundary-induced phase transition from free flow to congested traffic. In this paper, we study the ability of selected microscopic traffic models to reproduce a traffic breakdown, and we investigate its spatiotemporal dynamics. For our analysis, we use empirical traffic data from stationary loop detectors on a German Autobahn showing a spontaneous breakdown. We then present several methods to assess the results and compare the models with each other. In addition, we will also discuss some important modeling aspects and their impact on the resulting spatiotemporal pattern. The investigation of different downstream boundary conditions, for example, shows that the physical origin of the traffic breakdown may be artificially induced by the setup of...

  6. On the reproducibility of spatiotemporal traffic dynamics with microscopic traffic models

    Science.gov (United States)

    Knorr, Florian; Schreckenberg, Michael

    2012-10-01

    Traffic flow is a very prominent example of a driven non-equilibrium system. A characteristic phenomenon of traffic dynamics is the spontaneous and abrupt drop of the average velocity on a stretch of road leading to congestion. Such a traffic breakdown corresponds to a boundary-induced phase transition from free flow to congested traffic. In this paper, we study the ability of selected microscopic traffic models to reproduce a traffic breakdown, and we investigate its spatiotemporal dynamics. For our analysis, we use empirical traffic data from stationary loop detectors on a German Autobahn showing a spontaneous breakdown. We then present several methods to assess the results and compare the models with each other. In addition, we will also discuss some important modeling aspects and their impact on the resulting spatiotemporal pattern. The investigation of different downstream boundary conditions, for example, shows that the physical origin of the traffic breakdown may be artificially induced by the setup of the boundaries.

  7. On the reproducibility of spatiotemporal traffic dynamics with microscopic traffic models

    International Nuclear Information System (INIS)

    Traffic flow is a very prominent example of a driven non-equilibrium system. A characteristic phenomenon of traffic dynamics is the spontaneous and abrupt drop of the average velocity on a stretch of road leading to congestion. Such a traffic breakdown corresponds to a boundary-induced phase transition from free flow to congested traffic. In this paper, we study the ability of selected microscopic traffic models to reproduce a traffic breakdown, and we investigate its spatiotemporal dynamics. For our analysis, we use empirical traffic data from stationary loop detectors on a German Autobahn showing a spontaneous breakdown. We then present several methods to assess the results and compare the models with each other. In addition, we will also discuss some important modeling aspects and their impact on the resulting spatiotemporal pattern. The investigation of different downstream boundary conditions, for example, shows that the physical origin of the traffic breakdown may be artificially induced by the setup of the boundaries. (paper)

  8. The use of Grey System Theory in predicting the road traffic accident in Fars province in Iran

    Directory of Open Access Journals (Sweden)

    Ali Mohammadi

    2011-10-01

    Full Text Available Traffic accidents have become a more and more important factor that restrict the development of economy and threaten the safety of human beings. Considering the complexity and uncertainty of the influencing factors on traffic accidents, traffic accident forecasting can be regarded as a grey system with unknown and known information, so be analyzed by grey system theory. Grey models require only a limited amount of data to estimate the behavior of unknown systems. In this paper, first, the original predicted values of road traffic accidents are separately obtained by the GM (1,1 model, the Verhulst model and the DGM(2,1 model. The results of these models on predicting road traffic accident show that the forecasting accuracy of the GM(1,1 is higher than the Verhulst model and the DGM(2,1 model. Then, the GM(1,1 model is applied to predict road traffic accident in Fars province.

  9. Road pricing, traffic congestion and the environment

    Energy Technology Data Exchange (ETDEWEB)

    Button, K.J. [ed.] [George Mason University, Fairfax, VA (United States). Institute of Public Policy; Verhoef, E.T. [ed.] [Free University of Amsterdam (Netherlands). Dept. of Spatial Economics

    1998-12-31

    Various authors` works are drawn together in this book to explore historical and contemporaneous issues related to road pricing, as a means of easing traffic congestion and reducing atmospheric pollution from road transport. The need for energy efficiency as well as political and social pressure have led policy-makers away from road construction to meet all traffic growth towards traffic management. Despite having been suggested eighty years ago by Arthur Pigou, traffic management through road pricing stands up to analysis today, and should be put into practice. (UK)

  10. Robust Traffic Flow Management: Coevolutionary Approach Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We will develop a Coevolutionary Decision Support Tool (CDST) that explicitly incorporates weather uncertainty (non-probabilistically) into strategic Traffic Flow...

  11. Grad's moment method for vehicular traffic

    International Nuclear Information System (INIS)

    Based on a Boltzmann-like traffic equation and on Grad's moment method we construct a second-order continuum traffic flow model which is similar to the usual Navier–Stokes equations for viscous fluids. The viscosity coefficient appearing in our macroscopic traffic model is not introduced in an ad hoc way—as in other high-order traffic flow models—but comes into play via an iteration method akin to a Maxwellian procedure. As in some of the most popular second-order continuum models, our Navier–Stokes-like traffic model predicts the existence of a characteristic speed which is faster than the average velocity. However, by performing a linear stability analysis, it is possible to show that the faster characteristic speed does not constitute a deficiency of our second-order traffic model since it is related to a mode that decays quickly. Numerical simulations for different traffic scenarios show that the Navier–Stokes-like traffic model produces numerical results which are consistent with our daily experiences in real traffic

  12. A queuing model for road traffic simulation

    International Nuclear Information System (INIS)

    We present in this article a stochastic queuing model for the raod traffic. The model is based on the M/G/c/c state dependent queuing model, and is inspired from the deterministic Godunov scheme for the road traffic simulation. We first propose a variant of M/G/c/c state dependent model that works with density-flow fundamental diagrams rather than density-speed relationships. We then extend this model in order to consider upstream traffic demand as well as downstream traffic supply. Finally, we show how to model a whole raod by concatenating raod sections as in the deterministic Godunov scheme

  13. Air Traffic Management Research at NASA Ames

    Science.gov (United States)

    Davis, Thomas J.

    2012-01-01

    The Aviation Systems Division at the NASA Ames Research Center conducts leading edge research in air traffic management concepts and technologies. This overview will present concepts and simulation results for research in traffic flow management, safe and efficient airport surface operations, super density terminal area operations, separation assurance and system wide modeling and simulation. A brief review of the ongoing air traffic management technology demonstration (ATD-1) will also be presented. A panel discussion, with Mr. Davis serving as a panelist, on air traffic research will follow the briefing.

  14. A queuing model for road traffic simulation

    Energy Technology Data Exchange (ETDEWEB)

    Guerrouahane, N.; Aissani, D.; Bouallouche-Medjkoune, L. [University of Bejaia, LAMOS, 06000, Bejaia (Algeria); Farhi, N. [University Paris-Est, IFSTTAR, GRETTIA, F-77447 Marne-la-Vallée (France)

    2015-03-10

    We present in this article a stochastic queuing model for the raod traffic. The model is based on the M/G/c/c state dependent queuing model, and is inspired from the deterministic Godunov scheme for the road traffic simulation. We first propose a variant of M/G/c/c state dependent model that works with density-flow fundamental diagrams rather than density-speed relationships. We then extend this model in order to consider upstream traffic demand as well as downstream traffic supply. Finally, we show how to model a whole raod by concatenating raod sections as in the deterministic Godunov scheme.

  15. Temporal Statistic of Traffic Accidents in Turkey

    Science.gov (United States)

    Erdogan, S.; Yalcin, M.; Yilmaz, M.; Korkmaz Takim, A.

    2015-10-01

    Traffic accidents form clusters in terms of geographic space and over time which themselves exhibit distinct spatial and temporal patterns. There is an imperative need to understand how, where and when traffic accidents occur in order to develop appropriate accident reduction strategies. An improved understanding of the location, time and reasons for traffic accidents makes a significant contribution to preventing them. Traffic accident occurrences have been extensively studied from different spatial and temporal points of view using a variety of methodological approaches. In literature, less research has been dedicated to the temporal patterns of traffic accidents. In this paper, the numbers of traffic accidents are normalized according to the traffic volume and the distribution and fluctuation of these accidents is examined in terms of Islamic time intervals. The daily activities and worship of Muslims are arranged according to these time intervals that are spaced fairly throughout the day according to the position of the sun. The Islamic time intervals are never been used before to identify the critical hour for traffic accidents in the world. The results show that the sunrise is the critical time that acts as a threshold in the rate of traffic accidents throughout Turkey in Islamic time intervals.

  16. Urban Traffic Information Service Application Grid

    Institute of Scientific and Technical Information of China (English)

    Chang-Jun Jiang; Yang Luo; An-Qing Zhou; Lin Chen; Lei Liu; Zhao-Hui Zhang; Guo-Sun Zeng; Hong-Zhong Chen; Duo-Qian Miao; Yu Fang; Xiao-Feng Tao; Qing Zhi; Feng Yue

    2005-01-01

    Traffic information processing is very complicated because of dynamic, cooperative and distributed features. This paper describes the prototype system version 2.0 of Urban Traffic Information Service Application Grid (UTISAG),which is based on the previous version. In this version, a new architecture and more enhanced services are introduced.The remarkable characteristic of the new system is providing dynamic information services for travelers by grid technology. Therefore, the key research includes integrating large multi-source traffic data, forecasting route status, simulating regional traffic flow parallelly, and implementing optimum dynamic travel scheme based on massive GPS data.

  17. Influence of Traffic Mix on PCU Value of Vehicles under Heterogeneous Traffic Conditions

    OpenAIRE

    Prema Somanathan Praveen; Venkatachalam Thamizh Arasan

    2013-01-01

    Study of the basic traffic flow characteristics like traffic volume is the pre-requisites for the effective planning, design, operation and management of roadway systems. Traffic in developing countries like India is heterogeneous in nature consisting of vehicles of different categories with widely varying dimensional and operational characteristics. The moving vehicles of heterogeneous traffic occupy any convenient lateral position on the road without any lane discipline, based on the availa...

  18. Characteristics of ant-inspired traffic flow: Applying the social insect metaphor to traffic models

    OpenAIRE

    John, Alexander; Schadschneider, Andreas; Chowdhury, Debashish; Nishinari, Katsuhiro

    2009-01-01

    We investigate the organization of traffic flow on preexisting uni- and bidirectional ant trails. Our investigations comprise a theoretical as well as an empirical part. We propose minimal models of uni- and bi-directional traffic flow implemented as cellular automata. Using these models, the spatio-temporal organization of ants on the trail is studied. Based on this, some unusual flow characteristics which differ from those known from other traffic systems, like vehicular traffic or pedestri...

  19. Traffic Information Unit, Traffic Information System, Vehicle Management System, Vehicle, and Method of Controlling a Vehicle

    OpenAIRE

    Papp, Z.; Doodeman, G.J.N.; Nelisse, M.W.; Van der Sijs, J.; Theeuwes, J.A.C.; Driessen, B.J.F.

    2010-01-01

    A traffic information unit (MD1, MD2, MD3) according to the invention comprises a facility (MI) for tracking vehicle state information of individual vehicles present at a traffic infrastructure and a facility (T) for transmitting said vehicle state information to a vehicle (70B, 70E). A traffic information system may comprise a plurality of these traffic information units. The invention further comprises a vehicle management system (C) for a target vehicle (70B, 70E) that is capable of receiv...

  20. Evaluation of Traffic Model as a part of the Traffic Management System on highways

    OpenAIRE

    Pirc, Jure

    2008-01-01

    The present work focuses on the traffic model for the level of service determination as a part of the Traffic Management System on highways in Slovenia. Based on the traffic data acquisition from various types of detectors (microwave detectors, video detection cameras) the system is capable of determining the levels of service in real time. Using Variable Message Signs, the information is then provided to the end users-the drivers. The first part of the work summarizes the traffic flow theory...

  1. Sociological study on the course of the traffic system and the traffic accidents

    OpenAIRE

    Erjem, Yaşar

    2007-01-01

    The subject of this research is the operation of the traffic system and traffic accidents from a sociological perspective. In the research , the traffic system is taken as a sub-system of the social system. In this context the effects of the social, cultural and demographic factors on traffic accidents are examined . The data were collected from 681 people of whom 300 are drivers 300 pedestrians, 4 directors and 20 instructors of driving courses in Konya in Turkey. The research findings showe...

  2. Selecting noise source and traffic representations that capture urban traffic noise dynamics

    OpenAIRE

    CAN, Arnaud; Leclercq, Ludovic; Lelong, Joël

    2009-01-01

    Considering traffic dynamics greatly improves noise estimation in urban area. This can be achieved by coupling a dynamic traffic model with both noise emission laws and sound propagation calculation. Determining the relevant noise source and traffic representations to estimate classical noise descriptors (LAeq and statistical descriptors) near traffic signals has been recently studied. This research topic is extended in this paper to more specific descriptors which are able to capture noise d...

  3. Automatic Traffic Density Estimation and Vehicle Classification for Traffic Surveillance Systems using Neural Networks

    OpenAIRE

    Ozkurt, Celil; Camci, Fatih

    2009-01-01

    It is important to know the road traffic density real time especially in mega cities for signal control and effective traffic management. In recent years, video monitoring and surveillance systems have been widely used in traffic management. Hence, traffic density estimation and vehicle classification can be achieved using video monitoring systems. In most vehicle detection methods in the literature, only the detection of vehicles in frames of the given video is emphesized. However, further a...

  4. Timing of traffic lights and phase separation in two-dimensional traffic flow

    Science.gov (United States)

    Sun, Duo; Jiang, Rui; Wang, Bing-Hong

    2010-02-01

    In this paper, we study the effects of traffic light period in two-dimensional Biham-Middleton-Levine (BML) traffic flow model. It is found that a phase separation phenomenon, in which the system separates into coexistence of free flow and jam, could be observed in intermediate vehicle density range when traffic light period T⩾4. We have explained the reason of occurrence of phase separation and investigated its behavior in different traffic light period.

  5. REDUCTION IN PROBABILITY OF TRAFFIC CONGESTION ON HIGH-CLASS ROAD USING RAMP ACCESS CONTROL

    Directory of Open Access Journals (Sweden)

    R. Yu. Lagerev

    2016-02-01

    Full Text Available Мerging traffic junctions on high-class roads are considered as bottlenecks in the network and quality of their operation determines a probability for formation of traffic congestions. Investigations on congestion situations in the merging zones of ramp and freeway traffic flows have demonstrated that queuing ramp traffic flow leads to formation of so called “turbulence” effect due to re-arrangement of transport facilities and reduction in their speed on main road direction. Having high queuing traffic flow on main road the “turbulence” component can result in formation of an impact blow in the main traffic flow. It has been proved that an impact of the ramp traffic flow on congestion probability is higher in comparison with main road traffic flow. The paper makes it possible to establish that some transport facilities moving along a high-way simul taneously occupy two lanes in the merging traffic zones and they reduce capacity of the used road section. It is necessary to take into account this specific feature and it is necessary to pay attention to it in the zones of “turbulence” effect formation. The paper presents main approaches, methodology, principles and stages required for access control of high-class roads which are directed on higher quality of their operation including improvement of road traffic safety. The paper proposes a methodоlogy that allows to evaluate and optimize ramp control in the context of a transport queue length minimization at adjoining ramps for the purposes of probability reduction in transport congestion.

  6. The traffic crisis and a tale of two cities: Traffic and air quality in Bangkok and Mexico City

    Energy Technology Data Exchange (ETDEWEB)

    Pendakur, V.S.; Badami, M.G.

    1995-12-31

    This paper focuses on congestion management techniques, traffic congestion levels and air quality. By using data from Bangkok and Mexico City, it illustrates the need for drastic changes in transportation policy tools and techniques for congestion management and for improving environmental quality. New approaches to investment and regulatory policy analysis and implementation are suggested. This requires the inclusion of all costs and benefits (economic and ecological) in the policy matrix so that investment and regulatory policies act in unison. Megacities are dominant in social, political and economic terms. 30 to 60% of national GDP is typically produced in these cities. Their human and motor vehicle populations have been doubling every 15-20 and 6-10 years respectively. They also have the most severe traffic congestion and air quality problems. They have the nation`s highest incidence of poverty and absolute poverty. Large portions of their populations endure severely unhealthy housing and sanitation conditions. Following are important characteristics of urban transportation systems in the megacities: the city centres are heavily congested with motorized traffic; traffic crawl rates vary from 2 to 10 km/hr; car and motorcycle ownership are increasing at annual rates of 10-12% and 15-20% respectively; significant air pollution with no relief in sight; TDM strategies are primarily creating new supply of road capacity; fairly high transit trips with substantial transit investments; weak air pollution monitoring and enforcement; and fairly cheap fuel and high costs of vehicles.

  7. Traffic Light Control by Multiagent Reinforcement Learning Systems

    NARCIS (Netherlands)

    Bakker, B.; Whiteson, S.; Kester, L.J.H.M.; Groen, F.C.A.

    2010-01-01

    Traffic light control is one of the main means of controlling road traffic. Improving traffic control is important because it can lead to higher traffic throughput and reduced traffic congestion. This chapter describes multiagent reinforcement learning techniques for automatic optimization of traffi

  8. Traffic light control by multiagent reinforcement learning systems

    NARCIS (Netherlands)

    B. Bakker; S. Whiteson; L. Kester; F.C.A. Groen

    2010-01-01

    Traffic light control is one of the main means of controlling road traffic. Improving traffic control is important because it can lead to higher traffic throughput and reduced traffic congestion. This chapter describes multiagent reinforcement learning techniques for automatic optimization of traffi

  9. Influence of Traffic Mix on PCU Value of Vehicles under Heterogeneous Traffic Conditions

    Directory of Open Access Journals (Sweden)

    Prema Somanathan Praveen

    2013-09-01

    Full Text Available Study of the basic traffic flow characteristics like traffic volume is the pre-requisites for the effective planning, design, operation and management of roadway systems. Traffic in developing countries like India is heterogeneous in nature consisting of vehicles of different categories with widely varying dimensional and operational characteristics. The moving vehicles of heterogeneous traffic occupy any convenient lateral position on the road without any lane discipline, based on the availability of space. The interaction between moving vehicles under such traffic condition is highly complex in nature, which can be represented in terms of the amount of impedance caused to flow of traffic by a vehicle type in comparison with that of standard vehicle (passenger car. Passenger Car Unit (PCU can be an appropriate measure to represent the relative impedance caused by a vehicle in heterogeneous traffic. This paper is concerned with the application micro-simulation technique to derive equivalency values (PCU factors on a purely homogeneous (cars-only traffic stream as well as on a heterogeneous traffic stream for different categories of road vehicles over a wide range of traffic flow and compositions on four-lane divided urban roads in India. The PCU values obtained for the different types of vehicles, for a wide range of traffic volume and composition, indicate that the PCU values of a vehicle type significantly changes with change in traffic volume and composition.

  10. Simple and stable dynamic traffic engineering for provider scale ethernet

    OpenAIRE

    Teixeira, António Edgar Carvalho

    2010-01-01

    The high speeds and decreasing costs of Ethernet solutions has motivated providers’ interest in using Ethernet as the link layer technology in their backbone and aggregation networks. Provider scale Ethernet offers further advantages, providing not only an easy to manage solution for multicast traffic, but also transparent interconnection between clients’ LANs. These Ethernet deployments face altogether different design issues, requiring support for a significantly higher number of host...

  11. Can a decoupling of traffic and economic growth be envisaged?

    OpenAIRE

    MADRE,JL; BERRI,A; Papon, F.

    2002-01-01

    Sustainable development means three conditions: general economic growth for the present, preservation of natural resources in the long term and social equity. Personal transportation in the developed countries is relying more and more on the private car. Until now, economic growth has lead to income growth, which allows car ownership increase, which in turn favours urban sprawl, which itself requires an increased car ownership. Eventually, car traffic growth has followed economic growth. If t...

  12. Human resources for the control of road traffic injury

    OpenAIRE

    Mock Charles; Kobusingye Olive; Anh Le Vu; Afukaar Francis; Arreola-Risa Carlos

    2005-01-01

    The definition of the ideal numbers and distribution of human resources required for control of road traffic injury (RTI) is not as advanced as for other health problems. We can nonetheless identify functions that need to be addressed across the spectrum of injury control: surveillance; road safety (including infrastructure, vehicle design, and behaviour); and trauma care. Many low-cost strategies to improve these functions in low- or middle-income countries can be identified. For all these s...

  13. A database of anomalous traffic for assessing profile based IDS

    OpenAIRE

    Owezarski, Philippe

    2010-01-01

    This paper aims at proposing a methodology and the required tools for evaluating current IDS (commercial ones, as well as prototypes resulting from advanced research projects) capabilities of detecting attacks targeting the networks and their services. This methodology tries to be as realistic as possible and reproducible, i.e. it works with real attacks and real traffic in controlled environments. It especially relies on a database containing attack traces specifically created for that evalu...

  14. Nature inspired artificial intelligence based adaptive traffic flow distribution in computer network

    CERN Document Server

    Singh, Manoj Kumar

    2010-01-01

    Because of the stochastic nature of traffic requirement matrix, it is very difficult to get the optimal traffic distribution to minimize the delay even with adaptive routing protocol in a fixed connection network where capacity already defined for each link. Hence there is a requirement to define such a method, which could generate the optimal solution very quickly and efficiently. This paper presenting a new concept to provide the adaptive optimal traffic distribution for dynamic condition of traffic matrix using nature based intelligence methods. With the defined load and fixed capacity of links, average delay for packet has minimized with various variations of evolutionary programming and particle swarm optimization. Comparative study has given over their performance in terms of converging speed. Universal approximation capability, the key feature of feed forward neural network has applied to predict the flow distribution on each link to minimize the average delay for a total load available at present on t...

  15. Traffic Dynamics of Computer Networks

    CERN Document Server

    Fekete, Attila

    2008-01-01

    Two important aspects of the Internet, namely the properties of its topology and the characteristics of its data traffic, have attracted growing attention of the physics community. My thesis has considered problems of both aspects. First I studied the stochastic behavior of TCP, the primary algorithm governing traffic in the current Internet, in an elementary network scenario consisting of a standalone infinite-sized buffer and an access link. The effect of the fast recovery and fast retransmission (FR/FR) algorithms is also considered. I showed that my model can be extended further to involve the effect of link propagation delay, characteristic of WAN. I continued my thesis with the investigation of finite-sized semi-bottleneck buffers, where packets can be dropped not only at the link, but also at the buffer. I demonstrated that the behavior of the system depends only on a certain combination of the parameters. Moreover, an analytic formula was derived that gives the ratio of packet loss rate at the buffer ...

  16. Principled negotiation and distributed optimization for advanced air traffic management

    Science.gov (United States)

    Wangermann, John Paul

    Today's aircraft/airspace system faces complex challenges. Congestion and delays are widespread as air traffic continues to grow. Airlines want to better optimize their operations, and general aviation wants easier access to the system. Additionally, the accident rate must decline just to keep the number of accidents each year constant. New technology provides an opportunity to rethink the air traffic management process. Faster computers, new sensors, and high-bandwidth communications can be used to create new operating models. The choice is no longer between "inflexible" strategic separation assurance and "flexible" tactical conflict resolution. With suitable operating procedures, it is possible to have strategic, four-dimensional separation assurance that is flexible and allows system users maximum freedom to optimize operations. This thesis describes an operating model based on principled negotiation between agents. Many multi-agent systems have agents that have different, competing interests but have a shared interest in coordinating their actions. Principled negotiation is a method of finding agreement between agents with different interests. By focusing on fundamental interests and searching for options for mutual gain, agents with different interests reach agreements that provide benefits for both sides. Using principled negotiation, distributed optimization by each agent can be coordinated leading to iterative optimization of the system. Principled negotiation is well-suited to aircraft/airspace systems. It allows aircraft and operators to propose changes to air traffic control. Air traffic managers check the proposal maintains required aircraft separation. If it does, the proposal is either accepted or passed to agents whose trajectories change as part of the proposal for approval. Aircraft and operators can use all the data at hand to develop proposals that optimize their operations, while traffic managers can focus on their primary duty of ensuring

  17. Reduction of the air traffic's contribution to climate change: A REACT4C case study

    OpenAIRE

    Grewe, V; Champougny, T.; Matthes, Sigrun; Frömming, Christine; Brinkop, Sabine; Soevde, Amund; Irvine, Emma A.; Halscheidt, Lucia

    2014-01-01

    Air traffic alters the atmospheric composition and thereby contributes to climate change. Here we investigate the trans-Atlantic air traffic for one specific winter day and analyse, which routing changes were required to achieve a reduction in the air traffic’s contribution to climate change. We have applied an atmosphere-chemistry model to calculate so-called five dimensional climate cost functions (CCF), which describe the climate effect of a locally confined emission. The five dimensions r...

  18. CONDITIONS PROVOKING AGGRESSIVE DRIVING IN PERCEPTION OF DRIVERS AND ROAD TRAFFIC INSPECTORS

    OpenAIRE

    JENENKOVA OKSANA VJACHESLAVOVNA

    2012-01-01

    This article considers such a phenomenon like aggressive driving, which is the most dangerous violation, from the point of view of the road traffic safety. Analysis of the world statistical data shows the necessity of singling out young people, which manifest dangerous driving by car more often than other drivers and who are tended to road traffic traumatism the most. To improve work in this direction, it is required to understand, which conditions provoking aggressive driving exist in the pe...

  19. A review about multimodal traffic simulation techniques

    Directory of Open Access Journals (Sweden)

    DIGIAMPIETRI, L. A.

    2012-12-01

    Full Text Available One of the current challenges in urban planning concerns the urban transportation involving multi-mode transportation. One of the ways to evaluate different situations in order to make decisions of how, when and where to invest is using multimodal traffic simulation. This paper presents a review about multimodal traffic simulation, identifying the state of art and directions for future work.

  20. Floating car data for traffic monitoring

    DEFF Research Database (Denmark)

    Torp, Kristian; Lahrmann, Harry Spaabæk

    2005-01-01

    This paper describes a complete prototype system that uses Floating Car Data (FCD) for both automatic and manual detection of queues in traffic. The system is developed under EU’s Tempo program. The systems consists of small hardware units placed in mobile traffic report units (we use taxis...

  1. Border Effects in Passenger Air Traffic

    OpenAIRE

    Klodt, Henning

    2003-01-01

    National borders substantially matter in passenger air traffic. Empirical estimates based upon a new data set on domestic and international departures from German airports indicate that the German border reduces air traffic activity by a factor of four to five. This result adds a further piece of evidence to the significance of border effects in various kinds of economic activity.

  2. Women Traffic Officer Project. Final Report.

    Science.gov (United States)

    Department of California Highway Patrol, Sacramento, CA.

    To determine the feasibility of employing women as state traffic officers (STOs), the California Highway Patrol (CHP) conducted a two-year study. The CHP employed forty-one women and forty-two men as traffic officers and gave them the standard sixteen-week training given all new officers. After graduation, the officers were assigned to highway…

  3. Road traffic noise and incident myocardial infarction

    DEFF Research Database (Denmark)

    Sørensen, Mette; Andersen, Zorana Jovanovic; Nordsborg, Rikke B;

    2012-01-01

    Both road traffic noise and ambient air pollution have been associated with risk for ischemic heart disease, but only few inconsistent studies include both exposures.......Both road traffic noise and ambient air pollution have been associated with risk for ischemic heart disease, but only few inconsistent studies include both exposures....

  4. Statistical Physics Algorithms for Traffic Reconstruction

    OpenAIRE

    De La Fortelle, Arnaud; Lasgouttes, Jean-Marc; Furtlehner, Cyril

    2007-01-01

    Concepts and techniques from statistical physics inspired a new method for traffic prediction. This method is particularly suitable in settings where the only information available is floating car data. We propose a system, based on the Ising model of statistical physics, which both reconstructs and predicts the traffic in real time using a message-passing algorithm.

  5. Environmental protection and traffic regulation in Slovenia

    Directory of Open Access Journals (Sweden)

    Aljaš Plevnik

    1998-01-01

    Full Text Available The article summarises the proposed chapter on traffic in the National programme for environmental protection. The main theme focuses on the suggested goals and measures to reach sustainable development in Slovenia. The goals and measures are derived from the current situation and traffic development trends and their influence on the environment, from international guidelines and the current Slovene policies.

  6. Survivable Impairment-Aware Traffic Grooming

    NARCIS (Netherlands)

    Beshir, A.; Nuijts, R.; Malhotra, R.; Kuipers, F.

    2011-01-01

    Traffic grooming allows efficient utilization of network capacity by aggregating several independent traffic streams into a wavelength. In addition, survivability and impairment-awareness (i.e., taking into account the effect of physical impairments) are two important issues that have gained a lot o

  7. Mitochondrial Ion Channels

    Science.gov (United States)

    O’Rourke, Brian

    2009-01-01

    In work spanning more than a century, mitochondria have been recognized for their multifunctional roles in metabolism, energy transduction, ion transport, inheritance, signaling, and cell death. Foremost among these tasks is the continuous production of ATP through oxidative phosphorylation, which requires a large electrochemical driving force for protons across the mitochondrial inner membrane. This process requires a membrane with relatively low permeability to ions to minimize energy dissipation. However, a wealth of evidence now indicates that both selective and nonselective ion channels are present in the mitochondrial inner membrane, along with several known channels on the outer membrane. Some of these channels are active under physiological conditions, and others may be activated under pathophysiological conditions to act as the major determinants of cell life and death. This review summarizes research on mitochondrial ion channels and efforts to identify their molecular correlates. Except in a few cases, our understanding of the structure of mitochondrial ion channels is limited, indicating the need for focused discovery in this area. PMID:17059356

  8. ACCOUNT OF ROAD CONDITIONS WHILE INVESTIGATING TRAFFIC ACCIDENTS

    OpenAIRE

    D. D. Selioukov; I. I. Leonovich

    2014-01-01

    The paper considers problems on better traffic safety at government, authority, engineering and driver activity levels, account of road conditions while investigating traffic accidents. The paper also provides road defects mentioned in forensic transport examinations of traffic accidents.

  9. Analysis of Traffic Accidents Using Hazard Index Method: Case of Denizli

    Directory of Open Access Journals (Sweden)

    Cenk OZAN

    2010-03-01

    Full Text Available Traffic accidents that occur as a result of a combination of many factors are complex and difficult issue. Although many studies are carried out in order to reduce the number of traffic accidents in urban transportation networks, exactly prevention of traffic accidents which arise from human and environmental factors is impossible. Therefore, especially in the urban transportation networks, determining links which have an accident risk and taking required measures are very important. In this study, the hazard index has been used to determine links which have an accident risk. Transportation network which contains high traffic volume regions in Denizli has been selected as study area. In this network, data were collected to be used in the hazard index, hazard indexes were calculated for links and risk grading was conducted. Morning and evening peak hour speed and traffic volume surveys were carried out in order to be used in analyses. Results showed that hazard index method can be used in traffic accident risk analysis and it is determined that hazard index method can be used to form a basis for future studies about decreasing the number of traffic accidents.

  10. Effect of primary user traffic on sensing-throughput tradeoff for cognitive radios

    KAUST Repository

    Tang, Liang

    2011-04-01

    The effect of the primary user traffic on the performance of the secondary network is investigated for the tradeoff between the sensing quality and the achievable throughput. Numerical results show that the actual secondary network performance when the random departure or arrival of the primary user is taken into account is worse than the predicted secondary network performance in the literature assuming constant occupancy state of the primary user. The degree of degradation depends on the traffic intensity as well as the received signal-to-noise ratio at the secondary user. Also, unlike the conventional model where the occupancy state of the primary user is assumed constant, the optimal sensing time in the new model varies for different primary channel conditions when the primary user traffic is considered. © 2011 IEEE.

  11. A possible mechanism for self coordination of bi-directional traffic across nuclear pores

    CERN Document Server

    Kapon, Ruti; Mukamel, David; Reich, and Ziv

    2008-01-01

    Nuclear pore complexes are constantly confronted by large fluxes of macromolecules and macromolecular complexes that need to get into and out of the nucleus. Such bi-directional traffic occurring in a narrow channel can easily lead to jamming. How then is passage between the nucleus and cytoplasm maintained under the varying conditions that arise during the lifetime of the cell? Here, we address this question using computer simulations in which the behaviour of the ensemble of transporting cargoes is analyzed under different conditions. We suggest that traffic can exist in two distinct modes, depending on concentration of cargoes and dissociation rates of the transport receptor-cargo complexes from the pores. In one mode, which prevails when dissociation is quick and cargo concentration is low, transport in either direction proceeds uninterrupted by the other direction. The result is that overall-traffic-direction fluctuates rapidly and unsystematically between import and export. Remarkably, when cargo concen...

  12. Traffic flow dynamics data, models and simulation

    CERN Document Server

    Treiber, Martin

    2013-01-01

    This textbook provides a comprehensive and instructive coverage of vehicular traffic flow dynamics and modeling. It makes this fascinating interdisciplinary topic, which to date was only documented in parts by specialized monographs, accessible to a broad readership. Numerous figures and problems with solutions help the reader to quickly understand and practice the presented concepts. This book is targeted at students of physics and traffic engineering and, more generally, also at students and professionals in computer science, mathematics, and interdisciplinary topics. It also offers material for project work in programming and simulation at college and university level. The main part, after presenting different categories of traffic data, is devoted to a mathematical description of the dynamics of traffic flow, covering macroscopic models which describe traffic in terms of density, as well as microscopic many-particle models in which each particle corresponds to a vehicle and its driver. Focus chapters on ...

  13. Intelligent Model for Traffic Safety Applications

    Directory of Open Access Journals (Sweden)

    C. Chellappan

    2012-01-01

    Full Text Available Problem statement: This study presents an analysis on road traffic system focused on the use of communications to detect dangerous vehicles on roads and highways and how it could be used to enhance driver safety. Approach: The intelligent traffic safety application model is based on all traffic flow theories developed in the last years, leading to reliable representations of road traffic, which is of major importance in achieving the attenuation of traffic problems. The model also includes the decision making process from the driver in accelerating, decelerating and changing lanes. Results: The individuality of each of these processes appears from the model parameters that are randomly generated from statistical distributions introduced as input parameters. Conclusion: This allows the integration of the individuality factor of the population elements yielding knowledge on various driving modes at wide variety of situations.

  14. Traffic and Granular Flow ’03

    CERN Document Server

    Luding, Stefan; Bovy, Piet; Schreckenberg, Michael; Wolf, Dietrich

    2005-01-01

    These proceedings are the fifth in the series Traffic and Granular Flow, and we hope they will be as useful a reference as their predecessors. Both the realistic modelling of granular media and traffic flow present important challenges at the borderline between physics and engineering, and enormous progress has been made since 1995, when this series started. Still the research on these topics is thriving, so that this book again contains many new results. Some highlights addressed at this conference were the influence of long range electric and magnetic forces and ambient fluids on granular media, new precise traffic measurements, and experiments on the complex decision making of drivers. No doubt the “hot topics” addressed in granular matter research have diverged from those in traffic since the days when the obvious analogies between traffic jams on highways and dissipative clustering in granular flow intrigued both c- munities alike. However, now just this diversity became a stimulating feature of the ...

  15. Distributed traffic signal control using fuzzy logic

    Science.gov (United States)

    Chiu, Stephen

    1992-01-01

    We present a distributed approach to traffic signal control, where the signal timing parameters at a given intersection are adjusted as functions of the local traffic condition and of the signal timing parameters at adjacent intersections. Thus, the signal timing parameters evolve dynamically using only local information to improve traffic flow. This distributed approach provides for a fault-tolerant, highly responsive traffic management system. The signal timing at an intersection is defined by three parameters: cycle time, phase split, and offset. We use fuzzy decision rules to adjust these three parameters based only on local information. The amount of change in the timing parameters during each cycle is limited to a small fraction of the current parameters to ensure smooth transition. We show the effectiveness of this method through simulation of the traffic flow in a network of controlled intersections.

  16. Modeling Network Traffic in Wavelet Domain

    Directory of Open Access Journals (Sweden)

    Sheng Ma

    2004-12-01

    Full Text Available This work discovers that although network traffic has the complicated short- and long-range temporal dependence, the corresponding wavelet coefficients are no longer long-range dependent. Therefore, a "short-range" dependent process can be used to model network traffic in the wavelet domain. Both independent and Markov models are investigated. Theoretical analysis shows that the independent wavelet model is sufficiently accurate in terms of the buffer overflow probability for Fractional Gaussian Noise traffic. Any model, which captures additional correlations in the wavelet domain, only improves the performance marginally. The independent wavelet model is then used as a unified approach to model network traffic including VBR MPEG video and Ethernet data. The computational complexity is O(N for developing such wavelet models and generating synthesized traffic of length N, which is among the lowest attained.

  17. Traffic congestion in interconnected complex networks

    CERN Document Server

    Tan, Fei; Xia, Yongxiang; Tse, Chi K

    2014-01-01

    Traffic congestion in isolated complex networks has been investigated extensively over the last decade. Coupled network models have recently been developed to facilitate further understanding of real complex systems. Analysis of traffic congestion in coupled complex networks, however, is yet to come. In this paper, we try to explore the effect of interconnections on traffic congestion in interconnected BA scale-free networks. We find that assortative coupling can alleviate traffic congestion better than disassortative and random coupling when the node processing capacity is allocated based on node usage probability. Furthermore, the optimal coupling probability can be found for assortative coupling. However, three types of coupling preferences achieve similar traffic performance if all nodes share the same processing capacity. We analyze interconnected Internet AS-level graphs of Japan and South Korea and obtain similar results. Some practical suggestions are presented to optimize such real-world interconnect...

  18. A traffic-depended multi-buffer node architecture and an effective access technique under symmetric and asymmetric IP traffic scenarios for unslotted ring WDM MANs

    Science.gov (United States)

    Baziana, Peristera A.

    2016-09-01

    This study aims to put forward an extensive discussion about the increasing demand for available bandwidth to serve the multiple types of traffic in modern wavelength division multiplexing (WDM) metropolitan area networks (MANs). A traffic-depended multi-buffer node architecture in conjunction with an efficient asynchronous transmission WDM access (WDMA) protocol to serve the variable size Internet packets in ring MANs is proposed. The structure of the multi-buffer node architecture is determined by the probability distribution of each packet size category in the MAN traffic, providing storage and dropping events equity among the nodes. The adopted WDMA algorithm satisfies the requirement for high performance efficiency especially under high offered load, by taking care to optimally face the bandwidth fragmentation problem and to maximize the bandwidth exploitation, while it effectively avoids both the packets collisions over the wavelengths and the destination conflicts. Numerical results prove that the proposed network model achieves throughput improvement up to 334% as compared with the relative study of Pranggono and Elmirghani (2011). An analytical framework is developed for the protocol throughput predictions under both symmetric and asymmetric IP traffic scenarios. Also, the proposed protocol performance is thoroughly investigated through simulation results based on Poisson and self-similar traffic model statistics, for both traffic scenarios.

  19. Local traffic control of microregion

    Czech Academy of Sciences Publication Activity Database

    Homolová, Jitka; Nagy, Ivan

    Adelaide: Advanced Knowledge International, 2004 - (Andrýsek, J.; Kárný, M.; Kracík, J.), s. 161-171. (International Series on Advanced Intelligence.. 9). ISBN 0-9751004-5-9. [Workshop on Computer-Intensive Methods in Control and Data Processing 2004. Prague (CZ), 12.05.2004-14.05.2004] R&D Projects: GA MDS 1F43A/003/120 Grant ostatní: SOCRATES(XE) 110330-CP-1-2003-1-ES Institutional research plan: CEZ:AV0Z1075907 Keywords : traffic control * linear programming * Kalman filter Subject RIV: BC - Control Systems Theory http://library.utia.cas.cz/prace/20040054.pdf

  20. The international traffic in uranium

    International Nuclear Information System (INIS)

    How the international traffic in uranium, contrary to the spirit of the Non-Proliferation Treaty (NPT), is being carried out by the very nations who are signatories to the NPT is described. The US did not supply enriched uranium for commissioning Koeberg nuclear power plant of South Africa, because South Africa refused to accept full scope safeguards. However, South Africa could procure necessary supplies of enriched uranium, probably from the surplus stocks of enriched uranium of European countries. In contravention of UN sanctions, many European nations are also collaborating with South Africa in illegal mining of uranium in Namibia. All these goings on indicate that the NPT's main objective is not to prevent or reduce proliferation, but to deny nuclear technology to those brown and black nations which do not sign the NPT or do not accept the full scope safeguards. (M.G.B.)