WorldWideScience

Sample records for centralized traffic control

  1. Chaotic Control of Network Traffic

    Institute of Scientific and Technical Information of China (English)

    YANG Tan; CUI Yi-Dong; JIN Yue-Hui; CHENG Shi-Duan

    2009-01-01

    A method of chaotic control on network traffic is presented.By this method,the chaotic network traffic can be controlled to a pre-assigned equilibrium point according to chaotic prediction and the largest Lyapunov exponent of the traffic on congested link is reduced,thereby the probability of traffic burst and network congestion can be reduced.Numerical examples show that this method is effective.

  2. 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.

  3. Traffic jams: dynamics and control.

    Science.gov (United States)

    Orosz, Gábor; Wilson, R Eddie; Stépán, Gábor

    2010-10-13

    This introductory paper reviews the current state-of-the-art scientific methods used for modelling, analysing and controlling the dynamics of vehicular traffic. Possible mechanisms underlying traffic jam formation and propagation are presented from a dynamical viewpoint. Stable and unstable motions are described that may give the skeleton of traffic dynamics, and the effects of driver behaviour are emphasized in determining the emergent state in a vehicular system. At appropriate points, references are provided to the papers published in the corresponding Theme Issue.

  4. 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....

  5. 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

  6. Human Factors in Air Traffic Control

    Science.gov (United States)

    1982-04-01

    leaves him in a central role but provides some automated facilitiee to help him to do his 3ob. 7he concepto therefore have different emotional...which engender favourable attitudes towards them. Considering the amount of effort which goes into marketing commercial products, astonishinglXy...in air traffic control environments. Safety standards are clear and gentrally enforced, and the equipment currently marketed does not have emissions

  7. Development of River Traffic in the Traffic System of Central Croatia

    Directory of Open Access Journals (Sweden)

    Dragan Badanjak

    2006-05-01

    Full Text Available From the aspect of public transport of passengers andgoods, the traffic system in Central Croatia consists of road,rail, air and river subsystems. Regarding their share in the volumeof passenger and cargo transport as well as the carried outtransport operations in the traffic system of Central Croatia,road and rail traffic are the dominant traffic subsystems. Regardingits technical, technological, organizational and economicindicators, the river traffic system represents the less developedsubsystem of the traffic system of Central Croatia, andthe situation in this respect is not much different at the nationallevel either.The possibilities for the development of river traffic systemhave not been sufficiently used, although the potential trafficdemand for the transportation services are substantial, especiallywhen considering the river Sava which potentially offersa direct connection to the trunk European waterway. The advantagesof the Central Croatian location undoubtedly lie inthe traffic and geo-strategic position, but the value of this locationcan be used only then when the quality level of the trafficsystem and the construction level of the infrastructurecatch up with the ones in the developed European countries.The conditions for the traffic development are first of allstrong and daily faster changes in the strata, especially regardingthe implementation of new solutions and increasing theefficiency of the overall traffic system. It is precisely for thisreason that special interest should be to study the traffic valuesaccording to the available data, establish their possiblerules as function of time, and design appropriate mathematicalmodels with the aim of forecasting the traffic developmentin the future.

  8. 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.

  9. Bits of Internet traffic control

    OpenAIRE

    Vojnovic, Milan; Le Boudec, Jean Yves

    2005-01-01

    In this work, we consider four problems in the context of Internet traffic control. The first problem is to understand when and why a sender that implements an equation-based rate control would be TCP-friendly, or not—a sender is said to be TCP-friendly if, under the same operating conditions, its long-term average send rate does not exceed that of a TCP sender. It is an established axiom that some senders in the Internet would need to be TCP-friendly. An equation-based rate control sender pl...

  10. Bits of Internet Traffic Control

    OpenAIRE

    Vojnovic, Milan

    2003-01-01

    In this work, we consider four problems in the context of Internet traffic control. The first problem is to understand when and why a sender that implements an equation-based rate control would be TCP-friendly, or not—a sender is said to be TCP-friendly if, under the same operating conditions, its long-term average send rate does not exceed that of a TCP sender. It is an established axiom that some senders in the Internet would need to be TCP-friendly. An equation-based rate control sender pl...

  11. 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...

  12. Light signals for road traffic control.

    NARCIS (Netherlands)

    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

  13. TCP/IP Communication System for Controlling a Vehicular Traffic Intersection

    Directory of Open Access Journals (Sweden)

    Pedraza-Martínez Luis Fernando

    2013-10-01

    Full Text Available This paper describes the development of a prototype of a vehicular traffic controller, whose system of communication is based on the TCP/IP protocol, in order to re- motely monitor and control the operation of traffic lights for a vehicular intersection. The results show the times of communication between the central and the traffic controller. The conclusions highlight the importance of using the TCP/IP protocol in traffic light systems.

  14. The Analysis of Rail Traffic Control Systems

    Directory of Open Access Journals (Sweden)

    Darius Gaidelis

    2011-04-01

    Full Text Available The systems used for rail traffic control are compared. Their advantages and disadvantages are analysed. The present and future development of rail traffic control systems in various countries is considered. The possibility of adapting these microprocessor-based traffic control systems to the conditions of Lithuania is analysed. For this purpose, the analysis of goods transported by Lithuanian railways is made, and the non-uniform amount of goods transported on different road sections is evaluated. The number of the delayed trains due to the failure of traffic control systems in recent years is determined, the cost of installing a new microprocessor-based traffic control system at the railway station, as well as its repay time and the demand for employees are calculated. Article in Lithuanian

  15. Model Predictive Control for Integrating Traffic Control Measures

    NARCIS (Netherlands)

    Hegyi, A.

    2004-01-01

    Dynamic traffic control measures, such as ramp metering and dynamic speed limits, can be used to better utilize the available road capacity. Due to the increasing traffic volumes and the increasing number of traffic jams the interaction between the control measures has increased such that local cont

  16. Using Automated Planning for Traffic Signals Control

    Directory of Open Access Journals (Sweden)

    Matija Gulić

    2016-08-01

    Full Text Available Solving traffic congestions represents a high priority issue in many big cities. Traditional traffic control systems are mainly based on pre-programmed, reactive and local techniques. This paper presents an autonomic system that uses automated planning techniques instead. These techniques are easily configurable and modified, and can reason about the future implications of actions that change the default traffic lights behaviour. The proposed implemented system includes some autonomic properties, since it monitors the current traffic state, detects if the system is degrading its performance, sets up new sets of goals to be achieved by the planner, triggers the planner that generates plans with control actions, and executes the selected courses of actions. The obtained results in several artificial and real world data-based simulation scenarios show that the proposed system can efficiently solve traffic congestion.

  17. 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.

  18. A semi-decentralized control strategy for urban traffic

    OpenAIRE

    Farhi, Nadir; Nguyen Van Phu, Cyril; AMIR, Mouna; Haj Salem, Habib; LEBACQUE, Jean Patrick

    2015-01-01

    EWGT - Euro Working Group on Transportation, Delft, PAYS-BAS, 14-/07/2015 - 16/07/2015; We present in this article a semi-decentralized approach for urban traffic control, based on the TUC (Traffic responsive Urban Control) strategy. We assume that the control is centralized as in the TUC strategy, but we introduce a contention time window inside the cycle time, where antagonistic stages alternate a priority rule. The priority rule is set by applying green colours for given stages and yellow ...

  19. Controlling Disorder in Traffic Flow by Perturbation

    Institute of Scientific and Technical Information of China (English)

    LIKe-Ping; GAOZi-You; CHENTian-Lun

    2004-01-01

    We propose a new technique for controlling disorder in traffic system. A kind of control signal which can be considered as a perturbation has been designated at a given site (perturbation point) of the single-lane highway. When a vehicle passes the perturbation point at a time, the velocity of the vehicle will be changed at the next time by the perturbation. This technique is tested for the deterministic NaSch traffic model. The simulation results indicate that the traffic system can be transited from the disorder states to the order states, such as fixed-point, periodic motion, etc.

  20. Intelligent traffic control system using PLC

    Science.gov (United States)

    Barz, C.; Todea, C.; Latinovic, T.; Preradovic, D. M.; Deaconu, S.; Berdie, A.

    2016-08-01

    The paper presents the traffic control system controlled through a PLC which takes the signals from different sensors on roads. The global system developed ensures the coordination of four intersections, setting a path that respects coordination type green light, the integration of additional sensors, the implementation of probes radar to inform traffic participants about recommended speed for accessing the green state located in the intersection that will follow to cross.

  1. Traffic control: nursing practice calendar.

    Science.gov (United States)

    Rus, Linda; Cheesebro, Kathy; Nagra, Erica; Neff, Alaina

    2013-01-01

    Educating nurses on the multitude of new and updated best practices, changes in regulatory standards, new equipment, and enhanced technology creates an "information traffic jam." Multiple practice changes occurring simultaneously pose challenges for nurses to retain information to practice safely and effectively. An absence of coordination between various nursing and allied health teaching initiatives compounds this problem. A nursing practice calendar was developed to facilitate the prioritization, communication, and education of hospital-wide initiatives affecting nursing practice.

  2. 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

  3. Traffic Flow Control In Automated Highway Systems

    OpenAIRE

    Alvarez, Luis; Horowitz, Roberto

    1997-01-01

    This report studies the problem of traffic control in the Automated Highway System (AHS) hierarchical architecture of the California PATH program. A link layer controller for the PATH AHS architecture is presented. It is shown that the proposed control laws stabilize the vehicular density and flow around predetermined profiles.

  4. 36 CFR 4.12 - Traffic control devices.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Traffic control devices. 4.12... VEHICLES AND TRAFFIC SAFETY § 4.12 Traffic control devices. Failure to comply with the directions of a traffic control device is prohibited unless otherwise directed by the superintendent....

  5. 36 CFR 1004.12 - Traffic control devices.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Traffic control devices. 1004.12 Section 1004.12 Parks, Forests, and Public Property PRESIDIO TRUST VEHICLES AND TRAFFIC SAFETY § 1004.12 Traffic control devices. Failure to comply with the directions of a traffic control device...

  6. Bandwidth Optimization in Centralized WLANs for Different Traffic Types

    Directory of Open Access Journals (Sweden)

    Haines RJ

    2007-01-01

    Full Text Available Allocating bandwidth between different forms of coexisting traffic (such as web-browsing, streaming, and telephony within a wireless LAN is a challenging and interesting problem. Centralized coordination functions in wireless LANs offer several advantages over distributed approaches, having the benefit of a system overview at the controller, but obtaining a stable configuration of bandwidth allocation for the system is nontrivial. We present, review, and compare different mechanisms to achieve this end, and a number of different means of obtaining the configurations themselves. We describe an analytical model of the system under consideration and present two mathematical approaches to derive solutions for any system configuration and deployment, along with an adaptive feedback-based solution. We also describe a comprehensive simulation-based model for the problem, and a prototype that allows comparison of these approaches. Our investigations demonstrate that a self-adaptive dynamic approach far outperforms any static scheme, and that using a mathematical model to produce the configurations themselves confers several advantages.

  7. Situational Leadership in Air Traffic Control

    Science.gov (United States)

    Arvidsson, Marcus; Johansson, Curt R.; Ek, Asa; Akselsson, Roland

    2007-01-01

    In high-risk environments such as air traffic control, leadership on different levels plays a certain role in establishing, promoting, and maintaining a good safety culture. The current study aimed to investigate how leadership styles, leadership style adaptability, and over and under task leadership behavior differed across situations, operative conditions, leadership structures, and working tasks in an air traffic control setting. Study locations were two air traffic control centers in Sweden with different operational conditions and leadership structures, and an administrative air traffic management unit. Leadership was measured with a questionnaire based on Leader Effectiveness and Adaptability Description (LEAD; Blanchard, Zigarmi & Zigarmi, 2003; Hersey & Blanchard, 1988). The results showed that the situation had strong impact on the leadership in which the leadership behavior was more relationship oriented in Success and Group situations than in Hardship and Individual situations. The leadership adaptability was further superior in Success and Individual situations compared with Hardship and Group situations. Operational conditions, leadership structures and working tasks were, on the other hand, not associated with leadership behavior.

  8. Intelligent Control in Automation Based on Wireless Traffic Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kurt Derr; Milos Manic

    2007-08-01

    Wireless technology is a central component of many factory automation infrastructures in both the commercial and government sectors, providing connectivity among various components in industrial realms (distributed sensors, machines, mobile process controllers). However wireless technologies provide more threats to computer security than wired environments. The advantageous features of Bluetooth technology resulted in Bluetooth units shipments climbing to five million per week at the end of 2005 [1, 2]. This is why the real-time interpretation and understanding of Bluetooth traffic behavior is critical in both maintaining the integrity of computer systems and increasing the efficient use of this technology in control type applications. Although neuro-fuzzy approaches have been applied to wireless 802.11 behavior analysis in the past, a significantly different Bluetooth protocol framework has not been extensively explored using this technology. This paper presents a new neurofuzzy traffic analysis algorithm of this still new territory of Bluetooth traffic. Further enhancements of this algorithm are presented along with the comparison against the traditional, numerical approach. Through test examples, interesting Bluetooth traffic behavior characteristics were captured, and the comparative elegance of this computationally inexpensive approach was demonstrated. This analysis can be used to provide directions for future development and use of this prevailing technology in various control type applications, as well as making the use of it more secure.

  9. Intelligent Control in Automation Based on Wireless Traffic Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kurt Derr; Milos Manic

    2007-09-01

    Wireless technology is a central component of many factory automation infrastructures in both the commercial and government sectors, providing connectivity among various components in industrial realms (distributed sensors, machines, mobile process controllers). However wireless technologies provide more threats to computer security than wired environments. The advantageous features of Bluetooth technology resulted in Bluetooth units shipments climbing to five million per week at the end of 2005 [1, 2]. This is why the real-time interpretation and understanding of Bluetooth traffic behavior is critical in both maintaining the integrity of computer systems and increasing the efficient use of this technology in control type applications. Although neuro-fuzzy approaches have been applied to wireless 802.11 behavior analysis in the past, a significantly different Bluetooth protocol framework has not been extensively explored using this technology. This paper presents a new neurofuzzy traffic analysis algorithm of this still new territory of Bluetooth traffic. Further enhancements of this algorithm are presented along with the comparison against the traditional, numerical approach. Through test examples, interesting Bluetooth traffic behavior characteristics were captured, and the comparative elegance of this computationally inexpensive approach was demonstrated. This analysis can be used to provide directions for future development and use of this prevailing technology in various control type applications, as well as making the use of it more secure.

  10. MATLAB Simulation of Fuzzy Traffic Controller for Multilane Isolated Intersection

    OpenAIRE

    2010-01-01

    This paper presents a MATLAB simulation of fuzzy traffic controller for controlling traffic flow at multilane isolated signalized intersection. The controller is developed based on the waiting time and vehicles queue length at current green phase, and vehicles queue lengths at the other phases. For control strategy, the controllercontrols the traffic light timings and phase sequence to ensure smooth flow of traffic with minimal waiting time, queue length and delay time. In this research, the ...

  11. Validation of Air Traffic Controller Workload Models

    Science.gov (United States)

    1979-09-01

    SAR) tapes dtirinq the data reduc- tion phase of the project. Kentron International Limited provided the software support for the oroject. This included... ETABS ) or to revised traffic control procedures. The models also can be used to verify productivity benefits after new configurations have been...col- lected and processed manually. A preliminary compari- son has been made between standard NAS Stage A and ETABS operations at Miami. 1.2

  12. Chaos control in traffic flow models

    CERN Document Server

    Shahverdiev, E M; Shahverdiev, Elman Mohammed; Tadaki, Shin-ichi

    1998-01-01

    Chaos control in some of the one- and two-dimensional traffic flow dynamical models in the mean field theory is studied.One dimensional model is investigated taking into account the effect of random delay. Two dimensional model takes into account the effects of overpasses, symmetric distribution of cars and blockages of cars moving in the same direction. Chaos synchronization is performed within both replica and nonreplica approaches, and using parameter perturbation method.

  13. Air traffic control by distributed management in a MLS environment

    Science.gov (United States)

    Kreifeldt, J. G.; Parkin, L.; Hart, S.

    1977-01-01

    The microwave landing system (MLS) is a technically feasible means for increasing runway capacity since it could support curved approaches to a short final. The shorter the final segment of the approach, the wider the variety of speed mixes possible so that theoretically, capacity would ultimately be limited by runway occupance time only. An experiment contrasted air traffic control in a MLS environment under a centralized form of management and under distributed management which was supported by a traffic situation display in each of the 3 piloted simulators. Objective flight data, verbal communication and subjective responses were recorded on 18 trial runs lasting about 20 minutes each. The results were in general agreement with previous distributed management research. In particular, distributed management permitted a smaller spread of intercrossing times and both pilots and controllers perceived distributed management as the more 'ideal' system in this task. It is concluded from this and previous research that distributed management offers a viable alternative to centralized management with definite potential for dealing with dense traffic in a safe, orderly and expeditious manner.

  14. Self-Organized Control of Irregular or Perturbed Network Traffic

    CERN Document Server

    Helbing, D; Lebacque, J P; Helbing, Dirk; L\\"ammer, Stefan; Lebacque, Jean-Patrick

    2005-01-01

    We present a fluid-dynamic model for the simulation of urban traffic networks with road sections of different lengths and capacities. The model allows one to efficiently simulate the transitions between free and congested traffic, taking into account congestion-responsive traffic assignment and adaptive traffic control. We observe dynamic traffic patterns which significantly depend on the respective network topology. Synchronization is only one interesting example and implies the emergence of green waves. In this connection, we will discuss adaptive strategies of traffic light control which can considerably improve throughputs and travel times, using self-organization principles based on local interactions between vehicles and traffic lights. Similar adaptive control principles can be applied to other queueing networks such as production systems. In fact, we suggest to turn push operation of traffic systems into pull operation: By removing vehicles as fast as possible from the network, queuing effects can be ...

  15. MATLAB Simulation of Fuzzy Traffic Controller for Multilane Isolated Intersection

    Directory of Open Access Journals (Sweden)

    Azura Che Soh/Lai Guan Rhung

    2010-07-01

    Full Text Available This paper presents a MATLAB simulation of fuzzy traffic controller for controlling traffic flow at multilane isolated signalized intersection. The controller is developed based on the waiting time and vehicles queue length at current green phase, and vehicles queue lengths at the other phases. For control strategy, the controllercontrols the traffic light timings and phase sequence to ensure smooth flow of traffic with minimal waiting time, queue length and delay time. In this research, the isolated intersection model used consists of two lanes in each approach. Each approach has two different values of vehicles queue length and waiting time, respectively, at the intersection. The maximum values of vehicles queue length and waiting times are selected as the inputs to controller for optimized control of traffic flows at the intersection. A traffic model and fuzzy traffic controller are developed to evaluate the performance of traffic controllers underdifferent conditions. In the end, by comparing the experimental result obtained by the vehicle-actuated controller (VAC and fuzzy traffic controller (FTC which improves significant performance for intersections, we confirmed the efficiency of our intelligent controller based fuzzy inference system.

  16. 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.

  17. Research on Compiling Methods of Train Working Diagram Based on Centralized Traffic Control (“CTC”) System%基于 CTC调度集中系统列车运行图编制方法的研究

    Institute of Scientific and Technical Information of China (English)

    沈农华

    2014-01-01

    研究编制我院CTC调度集中系统的列车运行图,既可以填补综合实训系统的一项空白,使系统的整体功能得到提升,为教学提供更多的实训内容,又可以为新校区的实训基地沙盘的再建设积累经验,有着重要的现实意义。%the research and compilation of the train working diagram based on the centralized traf-fic control system (“CTC”) may fill up the vacancy in the comprehensive training system to upgrade the overall function of the system and to provide more training information to the teaching work and may accumulate experiences to the reconstruction of the sand board of the training base in the campus .It is of important significance to the practice .

  18. Tri-level programming model for combined urban traffic signal control and traffic flow guidance

    Institute of Scientific and Technical Information of China (English)

    孙智源; 陆化普; 屈闻聪

    2016-01-01

    In order to balance the temporal-spatial distribution of urban traffic flow, a model is established for combined urban traffic signal control and traffic flow guidance. With consideration of the wide use of fixed signal control at intersections, traffic assignment under traffic flow guidance, and dynamic characteristics of urban traffic management, a tri-level programming model is presented. To reflect the impact of intersection delay on traffic assignment, the lower level model is set as a modified user equilibrium model. The middle level model, which contains several definitional constraints for different phase modes, is built for the traffic signal control optimization. To solve the problem of tide lane management, the upper level model is built up based on nonlinear 0-1 integer programming. A heuristic iterative optimization algorithm (HIOA) is set up to solve the tri-level programming model. The lower level model is solved by method of successive averages (MSA), the middle level model is solved by non-dominated sorting genetic algorithm II (NSGA II), and the upper level model is solved by genetic algorithm (GA). A case study is raised to show the efficiency and applicability of the proposed modelling and computing method.

  19. Proactive Traffic Information Control in Emergency Evacuation Network

    Directory of Open Access Journals (Sweden)

    Zhengfeng Huang

    2015-01-01

    Full Text Available Traffic demand in emergency evacuation is usually too large to be effectively managed with reactive traffic information control methods. These methods adapt to the road traffic passively by publishing real-time information without consideration of the routing behavior feedback produced by evacuees. Other remedy measures have to be prepared in case of nonrecurring congestion under these methods. To use the network capacity fully to mitigate near-future evacuation traffic congestion, we propose proactive traffic information control (PTIC model. Based on the mechanism between information and routing behavior feedback, this model can change the route choice of evacuees in advance by dissipating strategic traffic information. Generally, the near-future traffic condition is difficult to accurately predict because it is uncertain in evacuation. Assume that the value of traffic information obeys certain distribution within a range, and then real-time traffic information may reflect the most-likely near-future traffic condition. Unlike the real-time information, the proactive traffic information is a selection within the range to achieve a desired level of the road network performance index (total system travel time. In the aspect of the solution algorithm, differential equilibrium decomposed optimization (D-EDO is proposed to compare with other heuristic methods. A field study on a road network around a large stadium is used to validate the PTIC.

  20. 49 CFR 236.828 - System, traffic control.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false System, traffic control. 236.828 Section 236.828..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.828 System, traffic control. A block signal system under which train movements are authorized by...

  1. Research on an Urban Traffic Control System Based on DGPS

    Institute of Scientific and Technical Information of China (English)

    张锦; 张姝慧; 曹继红

    2002-01-01

    The basic principles of GPS (Global Positioning System) and DGPS (Differential GPS) are described. The principle and structure of vehicle navigation systems, and its application to the urban traffic flow guidance are analyzed. Then, an area-coordinated adaptive control system based on DGPS and a traffic flow guidance information system based on DGPS are put forward, and their working principles and functions are researched. This is to provides a new way for the development of urban road traffic control systems.

  2. Selective data collection in vehicular networks for traffic control applications

    CERN Document Server

    Płaczek, Bartłomiej

    2011-01-01

    Vehicular sensor network (VSN) is an emerging technology, which combines wireless communication offered by vehicular ad hoc networks (VANET) with sensing devices installed in vehicles. VSN creates a huge opportunity to extend the road-side sensor infrastructure of existing traffic control systems. The efficient use of the wireless communication medium is one of the basic issues in VSN applications development. This paper introduces a novel method of selective data collection for traffic control applications, which provides a significant reduction in data amounts transmitted through VSN. The underlying idea is to detect the necessity of data transfers on the basis of uncertainty determination of the traffic control decisions. According to the proposed approach, sensor data are transmitted from vehicles to the control node only at selected time moments. Data collected in VSN are processed using on-line traffic simulation technique, which enables traffic flow prediction, performance evaluation of control strateg...

  3. Traffic Modelling for Moving-Block Train Control System

    Institute of Scientific and Technical Information of China (English)

    TANG Tao; LI Ke-Ping

    2007-01-01

    This paper presents a new cellular automaton (CA) model for train control system simulation.In the proposed CA model,the driver reactions to train movements are captured by some updated rules.The space-time diagram of traffic flow and the trajectory of train movement is used to obtain insight into the characteristic behavior of railway traffic flow.A number of simulation results demonstrate that the proposed CA model can be successfully used for the simulations of railway traffic.Not only the characteristic behavior of railway traffic flow can be reproduced,but also the simulation values of the minimum time headway are close to the theoretical values.

  4. Autonomous Traffic Signal Control Model with Neural Network Analogy

    CERN Document Server

    Ohira, T

    1997-01-01

    We propose here an autonomous traffic signal control model based on analogy with neural networks. In this model, the length of cycle time period of traffic lights at each signal is autonomously adapted. We find a self-organizing collective behavior of such a model through simulation on a one-dimensional lattice model road: traffic congestion is greatly diffused when traffic signals have such autonomous adaptability with suitably tuned parameters. We also find that effectiveness of the system emerges through interactions between units and shows a threshold transition as a function of proportion of adaptive signals in the model.

  5. Traffic noise and vehicle movement at a controlled intersection

    NARCIS (Netherlands)

    Salomons, E.M.

    2014-01-01

    Traffic noise at an intersection controlled by traffic lights shows noise level variations due to the alternating green and red lights for the different trafficstreams. Noise peaks caused by automobiles pulling up or passing by at highspeed may be quite annoying for people living near the intersecti

  6. Detecting Approaching Vehicles at Streets with No Traffic Control

    Science.gov (United States)

    Emerson, Robert Wall; Sauerburger, Dona

    2008-01-01

    This study assessed the ability of people with visual impairments to reliably detect oncoming traffic at crossing situations with no traffic control. In at least one condition, the participants could not hear vehicles to afford a safe crossing time when sound levels were as quiet as possible. Significant predictors of detection accounted for a…

  7. 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...

  8. Operating the railway traffic control system

    Directory of Open Access Journals (Sweden)

    Anton PEPEVNIK

    2011-01-01

    Full Text Available Due to the valid traffic policy and development strategy of the Republic of Slovenia, the Slovenian Railways have to consider the developmental and strategic aims of European railways. The perspective of progress is basically determined by skimming the European system development, by taking over the European system and managing the railway traffic in the connection with the European railway system.Technology and organization of the railway traffic system present the sum of all technological and organizational elements and processes that takes part in providing aims of the system. The aims are defined as solving transport problems in railway system. The term system is defined, from the formal mathematical viewpoint, as a whole that is usually complicated or even very much complicated. Therefore, the railway system is complex as well, and that is why it has to be managed precisely. In the narrow sense of meaning, technology and work organization both comprises a variety of means and procedures to realize basic activity that can be seen as a perfect unit, and that can be the process of passengers and freight transport in a transport system.Because of the prompt development of microelectronics and computer engineering, a new generation of electronic signal-safety devices appeared.All these changes from the past few years that have been introduced into railway technology, enable railway to become attractive and competitive to other means of traffic. Therefore, the Slovenian Railways have to follow novelties in traffic technology development and gradually modernize its railway network.

  9. Unattended vehicle detection for automatic traffic light control

    Science.gov (United States)

    Abdel Hady, Aya Salama; Moustafa, Mohamed

    2013-12-01

    Machine vision based traffic light control depends mainly on measuring traffic statistics at cross roads. Most of the previous studies have not taken unattended vehicles into consideration when calculating either the traffic density or the traffic flow. In this paper, we propose incorporating unattended vehicles into a new metric for measuring the traffic congestion. In addition to the vehicle motion analysis, opening the driver's side door is an important indicator that this vehicle is going to be unattended. Therefore, we focus in this paper on presenting how to detect this event for stationary vehicles from a live camera or a video feed. Through a set of experiments, we have found out that a Scale Invariant Feature Transform (SIFT) feature-descriptor with a Support Vector Machines (SVM) classifier was able to successfully classify open-door vehicles from closed-door ones in 96.7% of our test dataset.

  10. Traffic improvement and transportation pollution control in Xiamen

    Energy Technology Data Exchange (ETDEWEB)

    Dongxing Yuan; Zilin, Wu

    1996-12-31

    in this paper, the urban traffic improvement and transportation control in Xiamen are highlighted. Xiamen is a port city and an economical special zone of China. As the economy grows, the transportation is developing dramatically and becoming the key for further economic development. The air quality is threatened by the rapid growth of the vehicles in the city. The most urgent task in improving urban traffic is to establish a sound traffic system. The municipal government takes great effort to improve the traffic condition, as well as to reduce green house gases and protect air environment. Some management and technical measures are carried out. Those management measures are mainly as follows: (1) systematic planning of the city arrangement and city functional division, and integrated planning of the urban roads system, (2) putting great emphasis on tail gas monitoring and management, and (3) establishing optimized utilization of motor vehicles. Those included in the main technical measures are (1) making the roads clear, (2) enlarging traffic capacity, and (3) developing the public transport. The most urgent task in improving urban traffic is to establish a sound traffic system. The city municipal government and Transportation Management Bureau plan to make a series of reforms to improve the urban traffic condition, such as building high quality road around the city, reducing the number of one way roads and replacing gasoline buses with electric buses. An optimized traffic system of Xiamen, taking public transport as the main means, is the key to meet the needs of both traffic improvement and urban transportation pollution control.

  11. Air Traffic Control automation: for humans or people?

    OpenAIRE

    Brooker, Peter

    2005-01-01

    Are air traffic controllers humans or people? At first sight, this seems a very odd question, given that ‘humans’ and ‘people’ are near-synonyms in the dictionary and everyday usage. However, in research on air traffic control (ATC) automation the phrase ‘human-centred’ is used to mean particular aspects of people: for example, it does not usually address their motivations for embracing change or cover organisational behaviour issues. The objective here is to try to understa...

  12. Road Traffic Control Based on Genetic Algorithm for Reducing Traffic Congestion

    Science.gov (United States)

    Shigehiro, Yuji; Miyakawa, Takuya; Masuda, Tatsuya

    In this paper, we propose a road traffic control method for reducing traffic congestion with genetic algorithm. In the not too distant future, the system which controls the routes of all vehicles in a certain area must be realized. The system should optimize the routes of all vehicles, however the solution space of this problem is enormous. Therefore we apply the genetic algorithm to this problem, by encoding the route of all vehicles to a fixed length chromosome. To improve the search performance, a new genetic operator called “path shortening” is also designed. The effectiveness of the proposed method is shown by the experiment.

  13. Task Analysis Assessment on Intrastate Bus Traffic Controllers

    Science.gov (United States)

    Yen Bin, Teo; Azlis-Sani, Jalil; Nur Annuar Mohd Yunos, Muhammad; Ismail, S. M. Sabri S. M.; Tajedi, Noor Aqilah Ahmad

    2016-11-01

    Public transportation acts as social mobility and caters the daily needs of the society for passengers to travel from one place to another. This is true for a country like Malaysia where international trade has been growing significantly over the past few decades. Task analysis assessment was conducted with the consideration of cognitive ergonomic view towards problem related to human factors. Conducting research regarding the task analysis on bus traffic controllers had allowed a better understanding regarding the nature of work and the overall monitoring activities of the bus services. This paper served to study the task analysis assessment on intrastate bus traffic controllers and the objectives of this study include to conduct task analysis assessment on the bus traffic controllers. Task analysis assessment for the bus traffic controllers was developed via Hierarchical Task Analysis (HTA). There are a total of five subsidiary tasks on level one and only two were able to be further broken down in level two. Development of HTA allowed a better understanding regarding the work and this could further ease the evaluation of the tasks conducted by the bus traffic controllers. Thus, human error could be reduced for the safety of all passengers and increase the overall efficiency of the system. Besides, it could assist in improving the operation of the bus traffic controllers by modelling or synthesizing the existing tasks if necessary.

  14. Distributed Air Traffic Control : A Human Safety Perspective

    CERN Document Server

    Nikumbh, Sarvesh; Vartak, Rahul

    2011-01-01

    The issues in air traffic control have so far been addressed with the intent to improve resource utilization and achieve an optimized solution with respect to fuel comsumption of aircrafts, efficient usage of the available airspace with minimal congestion related losses under various dynamic constraints. So the focus has almost always been more on smarter management of traffic to increase profits while human safety, though achieved in the process, we believe, has remained less seriously attended. This has become all the more important given that we have overburdened and overstressed air traffic controllers managing hundreds of airports and thousands of aircrafts per day. We propose a multiagent system based distributed approach to handle air traffic ensuring complete human (passenger) safety without removing any humans (ground controllers) from the loop thereby also retaining the earlier advantages in the new solution. The detailed design of the agent system, which will be easily interfacable with the existin...

  15. HIGH LEVEL MODELLING OF REAL TIME TRAFFIC LIGHT CONTROLLER

    Directory of Open Access Journals (Sweden)

    ADITYA MANDLOI

    2012-12-01

    Full Text Available The objective of this paper is to design and implement traffic control system. The system developed is able to sense the presence of vehicles within certain range by setting the appropriate duration for the traffic signals to react accordingly. By employing logical functions to calculate the appropriate timing for the signals toilluminate, the system can help to solve the problem of traffic congestion. The use of FPGAs (Field Programmable Gate Arrays is an interesting new phenomenon in VLSI development. FPGAs offer all of thefeatures needed to implement most complex designs. Hardware simulation tests were successfully performed on the algorithm implemented into a FPGA (Field Programmable Gate Arrays. The main object of the paper is to design a Real Time Traffic Light Controller (RTTLC using VHDL and implement the RTTLC in XILINX SPARTAN - 3 FPGA.

  16. From Cellular Attractor Selection to Adaptive Signal Control for Traffic Networks

    Science.gov (United States)

    Tian, Daxin; Zhou, Jianshan; Sheng, Zhengguo; Wang, Yunpeng; Ma, Jianming

    2016-03-01

    The management of varying traffic flows essentially depends on signal controls at intersections. However, design an optimal control that considers the dynamic nature of a traffic network and coordinates all intersections simultaneously in a centralized manner is computationally challenging. Inspired by the stable gene expressions of Escherichia coli in response to environmental changes, we explore the robustness and adaptability performance of signalized intersections by incorporating a biological mechanism in their control policies, specifically, the evolution of each intersection is induced by the dynamics governing an adaptive attractor selection in cells. We employ a mathematical model to capture such biological attractor selection and derive a generic, adaptive and distributed control algorithm which is capable of dynamically adapting signal operations for the entire dynamical traffic network. We show that the proposed scheme based on attractor selection can not only promote the balance of traffic loads on each link of the network but also allows the global network to accommodate dynamical traffic demands. Our work demonstrates the potential of bio-inspired intelligence emerging from cells and provides a deep understanding of adaptive attractor selection-based control formation that is useful to support the designs of adaptive optimization and control in other domains.

  17. Joint optimization traffic signal control for an urban arterial road

    Institute of Scientific and Technical Information of China (English)

    LI Yin-fei; CHEN Shu-ping

    2009-01-01

    This paper considers the optimal traffic signal setting for an urban arterial road. By introducing the concepts of synchronization rate and non-synchronization degree, a mathematical model is constructed and an optimization problem is posed. Then, a new iterative algorithm is developed to solve this optimal traffic control signal setting problem. Convergence properties for this iterative algorithm are established. Finally, a numerical example is solved to illustrate the effectiveness of the method.

  18. 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.

  19. Measurement of Temporal Awareness in Air Traffic Control

    Science.gov (United States)

    Rantanen, E.M.

    2009-01-01

    Temporal awareness, or level 3 situation awareness, is critical to successful control of air traffic, yet the construct remains ill-defined and difficult to measure. This research sought evidence for air traffic controllers awareness of temporal characteristics of their tasks in data from a high-fidelity system evaluation simulation. Five teams of controllers worked on four scenarios with different traffic load. Several temporal parameters were defined for each task controllers performed during a simulation run and their actions on the tasks were timed relative to them. Controllers showed a strong tendency to prioritize tasks according to a first come, first served principle. This trend persisted as task load increased. Also evident was awareness of the urgency of tasks, as tasks with impending closing of a window of opportunity were performed before tasks that had longer time available before closing of the window.

  20. Engineering Social Justice into Traffic Control for Self-Driving Vehicles?

    Science.gov (United States)

    Mladenovic, Milos N; McPherson, Tristram

    2016-08-01

    The convergence of computing, sensing, and communication technology will soon permit large-scale deployment of self-driving vehicles. This will in turn permit a radical transformation of traffic control technology. This paper makes a case for the importance of addressing questions of social justice in this transformation, and sketches a preliminary framework for doing so. We explain how new forms of traffic control technology have potential implications for several dimensions of social justice, including safety, sustainability, privacy, efficiency, and equal access. Our central focus is on efficiency and equal access as desiderata for traffic control design. We explain the limitations of conventional traffic control in meeting these desiderata, and sketch a preliminary vision for a next-generation traffic control tailored to address better the demands of social justice. One component of this vision is cooperative, hierarchically distributed self-organization among vehicles. Another component of this vision is a priority system enabling selection of priority levels by the user for each vehicle trip in the network, based on the supporting structure of non-monetary credits.

  1. Controlling traffic jams by time modulating the safety distance

    DEFF Research Database (Denmark)

    Gaididei, Yu B.; Gorria, C.; Berkemer, R.

    2013-01-01

    in the nonmodulated case, while it is a decreasing function in the opposite case. In other words, the safety distance time modulation facilitates car propagation in the case when the mean distance between cars in the congestive traffic is less than h and hinders it when the neighboring cars in the flow are well......The possibility of controlling traffic dynamics by applying high-frequency time modulation of traffic flow parameters is studied. It is shown that the region of the car density where the uniform (free) flow is unstable changes in the presence of time modulation compared with the unmodulated case....... This region shrinks when the speed-up of cars does not exceed some critical value and expands in the opposite case. The flux of the time-modulated flow is an increasing function of the amplitude of the modulation for traffic flows whose density is larger than 1/h where h is the safety distance...

  2. FAA Air Traffic Control Operations Concepts. Volume 5. ATCT/TCCC (airport Traffic Control Tower/Tower Control Computer Complex) Tower Controllers

    Science.gov (United States)

    1988-07-29

    MANAGEMENI RESIRICTI ".NS FO-DREFF’-ECT ON~ SEQUENCE J AS NECESSARY ’T2.1.1.7 ,I ? c II PROJECT AIRCRAFT/ VEHICLE PLA,"tJD TIME/ P, SITI•lO PRLE LE...REVIEW CURRENT AND R/A TRAFFIC. WEATHER, ALL LOGICAL N/A M H PROJECTED TRAFFIC TRAFFIC MANAGEMENI DISPLAYS STATUS/ WEATHER INFORMATON T3.0.3 MANAGING...STATEMENTS OBJECTS OBJECTS T3.4.1.5 DISCUSS TRAFFIC MANAGEMENI RESTRICTION PROCEDURES NITH CONTROLLER/ PILOT TASK TYPE: VC COORD MEDIA: V FREQUENCY: MED

  3. CONTROLLING TRAFFIC FLOW IN MULTILANE-ISOLATED INTERSECTION USING ANFIS APPROACH TECHNIQUES

    OpenAIRE

    2015-01-01

    Many controllers have applied the Adaptive Neural-Fuzzy Inference System (ANFIS) concept for optimizing the controller performance. However, there are less traffic signal controllers developed using the ANFIS concept. ANFIS traffic signal controller with its fuzzy rule base and its ability to learn from a set of sample data could improve the performance of Existing traffic signal controlling system to reduce traffic congestions at most of the busy traffic intersections in city such as Kuala L...

  4. Traffic Adaptive Distributed Backoff Control Mechanism for Cluster-Based IEEE802.15.4 WSNs with Traffic Fluctuations

    Science.gov (United States)

    Mori, Kazuo; Naito, Katsuhiro; Kobayashi, Hideo

    The traffic adaptive 2-level active period control has been proposed as a traffic adaptation mechanism to handle temporal and spatial (geographical) traffic fluctuations in cluster-based wireless sensor networks (WSNs) employing IEEE802.15.4 medium access control (MAC). This paper proposes a traffic adaptive distributed backoff control mechanism for cluster-based WSNs with the traffic adaptive 2-level active period control to enhance the system performance, especially transmission performance. The proposed mechanism autonomously adjusts the starting time of the backoff procedure for channel accesses in the contention access period (CAP) specified by the IEEE802.15.4 MAC, and then distributes the channel access timing over a wide range within the CAP, which can mitigate channel access congestion. The results of computer simulations show that the proposed mechanism can improve the transmission delay performance while keeping the enhancement in throughput and energy consumption at the cluster-based WSNs under non-uniform traffic environments.

  5. Fatigue Minimization Work Shift Scheduling for Air Traffic Controllers

    Directory of Open Access Journals (Sweden)

    Ta-Chung Wang

    2013-05-01

    Full Text Available It is common for Air Traffic Controllers to control air traffic during the night and to experience fatigue. Although fatigue is not the direct cause of aviation accidents, 21 percent of accidents are fatigue-related. Therefore countries and companies have tried to regulate work hours to avoid extreme fatigue, thus decreasing human error resulting from fatigue. However, these regulations may not reflect that actual fatigue variation and fatigue levels can be decreased still more by scheduling appropriately. This paper focuses on optimal work shift scheduling to reduce air traffic controller fatigue. First, a mathematical model is established to describe fatigue levels. The objective function is to reduce the fatigue peak produced by work shifts as much as possible. Various constraints, such as holidays and manpower requirements are considered. The optimization problem is then solved using integer programming. We take a sample schedule and draw conclusions by comparing our results with the original fatigue levels.

  6. Speed limit and ramp meter control for traffic flow networks

    Science.gov (United States)

    Goatin, Paola; Göttlich, Simone; Kolb, Oliver

    2016-07-01

    The control of traffic flow can be related to different applications. In this work, a method to manage variable speed limits combined with coordinated ramp metering within the framework of the Lighthill-Whitham-Richards (LWR) network model is introduced. Following a 'first-discretize-then-optimize' approach, the first order optimality system is derived and the switch of speeds at certain fixed points in time is explained, together with the boundary control for the ramp metering. Sequential quadratic programming methods are used to solve the control problem numerically. For application purposes, experimental setups are presented wherein variable speed limits are used as a traffic guidance system to avoid traffic jams on highway interchanges and on-ramps.

  7. Data requirements for traffic control on a macroscopic level

    NARCIS (Netherlands)

    Knoop, V.L.; Van Lint, J.W.C.; Hoogendoorn, S.P.

    2011-01-01

    With current techniques, traffic monitoring and control is a data intensive process. Network control on a higher level, using high level variables, can make this process less data demanding. The macroscopic fundamental diagram relates accumulation, i.e. the number of vehicles in an area, to the netw

  8. Deadlock-free traffic control with geometrical critical sections

    NARCIS (Netherlands)

    Schoute, Albert L.; Bouwens, Peter J.; Backer, E.

    1994-01-01

    Traffic control of vehicles on pre-planned paths may be based on critical sections where vehicles have to control their velocity mutually in order to avoid collisions. By analysing the geometry of critical sections carefully deadlock situations can be recognised and situations where vehicles may sha

  9. Model-Based Traffic Control for Sustainable Mobility

    NARCIS (Netherlands)

    Zegeye, S.K.

    2011-01-01

    Computationally efficient dynamic fuel consumption, emissions, and dispersion of emissions models are developed. Fast and practically feasible model-based controller is proposed. Using the developed models, the controller steers the traffic flow in such a way that a balanced trade-off between the t

  10. Traffic behavior of mixed traffic flow with two kinds of different self-stabilizing control vehicles

    Science.gov (United States)

    Li, Zhipeng; Li, Wenzhong; Xu, Shangzhi; Qian, Yeqing; Sun, Jian

    2015-10-01

    In this paper, we propose a heterogeneous car following model in terms of an extension to the original optimal velocity model characterizing two classes of different self-stabilizing control vehicles. Linear stability analysis method is utilized to the extended model, for purpose to explore how the varying percentages of the vehicles with short-duration self-stabilizing control influence the stability of the heterogeneous traffic flow. We obtain the neutral stability lines for different percentages of two classes of vehicles, with finding that the traffic flow trends to stable with the decrease of the percentage for short-duration self-stabilizing control vehicles. Moreover, we explore a special case that the same numbers of two different classes of vehicles with self-stabilizing control. We theoretically derive the stability condition of the special case, and conclude the effect of the average value and the standard deviation of two time gaps, on the heterogeneous traffic stability. At last, direct simulations are conducted to verify the conclusion of theoretical analysis.

  11. 78 FR 36132 - National Standards for Traffic Control Devices; Manual on Uniform Traffic Control Devices for...

    Science.gov (United States)

    2013-06-17

    ... books would cause unnecessary confusion because users would have to determine how to correctly apply the... experience the same fate as the Traffic Engineering Manual, which was developed to supplement the 1978...

  12. FL-FN-MOGA Based Traffic Signal Control

    Institute of Scientific and Technical Information of China (English)

    魏武; 张毅

    2003-01-01

    In this paper, a traffic signal control method based on fuzzy logic (FL), fuzzy-neuro (FN) and multi-objective genetic algorithms (MOGA) for an isolated four-approach intersection with through and left-turning movements is presented. This method has an adaptive signal timing ability, and can make adjustments to signal timing in response to observed changes. The "urgency degree" term, which can describe the different user's demand for green time is used in decision-making by which strategy of signal timing can be determined. Using a fuzzy logic controller, we can determine whether to extend or terminate the current signal phase and select the sequences of phases. In this paper, a method based on fuzzy-neuro can be used to predict traffic parameters used in fuzzy logic controller. The feasibility of using a multi-objective genetic algorithm (MOGA) to find a group of optimizing sets of parameters for fuzzy logic controller depending on different objects is also demonstrated. Simulation results show that the proposed methed is effecfive to adjust the signal timing in response to changing traffic conditions on a real-time basis, and the controller can produce lower vehicle delays and percentage of stopped vehicles than a traffic-actuated controller.

  13. A Sarsa(λ-Based Control Model for Real-Time Traffic Light Coordination

    Directory of Open Access Journals (Sweden)

    Xiaoke Zhou

    2014-01-01

    Full Text Available Traffic problems often occur due to the traffic demands by the outnumbered vehicles on road. Maximizing traffic flow and minimizing the average waiting time are the goals of intelligent traffic control. Each junction wants to get larger traffic flow. During the course, junctions form a policy of coordination as well as constraints for adjacent junctions to maximize their own interests. A good traffic signal timing policy is helpful to solve the problem. However, as there are so many factors that can affect the traffic control model, it is difficult to find the optimal solution. The disability of traffic light controllers to learn from past experiences caused them to be unable to adaptively fit dynamic changes of traffic flow. Considering dynamic characteristics of the actual traffic environment, reinforcement learning algorithm based traffic control approach can be applied to get optimal scheduling policy. The proposed Sarsa(λ-based real-time traffic control optimization model can maintain the traffic signal timing policy more effectively. The Sarsa(λ-based model gains traffic cost of the vehicle, which considers delay time, the number of waiting vehicles, and the integrated saturation from its experiences to learn and determine the optimal actions. The experiment results show an inspiring improvement in traffic control, indicating the proposed model is capable of facilitating real-time dynamic traffic control.

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

    Directory of Open Access Journals (Sweden)

    John L. McLin

    2011-01-01

    Full Text Available 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 using traffic microsimulation demonstrates that it has the potential to improve system conditions during traffic incidents. In addition, several enhancements were identified which will make the system more robust in a real traffic control setting. An assessment of the control system elements indicates that there are no substantial technical barriers in implementing this system in a large traffic network.

  15. Stability analysis of traffic flow with extended CACC control models

    Science.gov (United States)

    Ya-Zhou, Zheng; Rong-Jun, Cheng; Siu-Ming, Lo; Hong-Xia, Ge

    2016-06-01

    To further investigate car-following behaviors in the cooperative adaptive cruise control (CACC) strategy, a comprehensive control system which can handle three traffic conditions to guarantee driving efficiency and safety is designed by using three CACC models. In this control system, some vital comprehensive information, such as multiple preceding cars’ speed differences and headway, variable safety distance (VSD) and time-delay effect on the traffic current and the jamming transition have been investigated via analytical or numerical methods. Local and string stability criterion for the velocity control (VC) model and gap control (GC) model are derived via linear stability theory. Numerical simulations are conducted to study the performance of the simulated traffic flow. The simulation results show that the VC model and GC model can improve driving efficiency and suppress traffic congestion. Project supported by the National Natural Science Foundation of China (Grant Nos. 71571107 and 11302110). The Scientific Research Fund of Zhejiang Province, China (Grant Nos. LY15A020007, LY15E080013, and LY16G010003). The Natural Science Foundation of Ningbo City (Grant Nos. 2014A610030 and 2015A610299), the Fund from the Government of the Hong Kong Administrative Region, China (Grant No. CityU11209614), and the K C Wong Magna Fund in Ningbo University, China.

  16. Dynamic one-way traffic control in automated transportation systems

    NARCIS (Netherlands)

    Ebben, M; van der Zee, DJ

    2004-01-01

    In a project on underground freight transportation using Automated Guided Vehicles, single lanes for traffic in two directions are constructed to reduce infrastructure investment. Intelligent control rules are required to manage vehicle flows such, that collision is avoided and waiting times are min

  17. Model based monitoring for industrial and traffic noise control

    NARCIS (Netherlands)

    Eerden, F.J.M. van der; Binnerts, B.; Graafland, F.

    2015-01-01

    Noise control starts by understanding the actual noise situation. Especially for situations where the distance between industrial and traffic noise sources and a local community is in the order of one kilometer or more, it may not be clear what sources are the main contributors to annoyance. Then a

  18. Integration of Predictive Routing Information with Dynamic Traffic Signal Control

    Science.gov (United States)

    1994-05-01

    vehicles without the on-board guidance aid (Harris, S., Rabone , A., et.al., 1992). The simulation developed was called ROute GUidance Simulation (ROGUS...Florida. Harris, S., Rabone , A., et.al. 1992. ROGUS: A Simulation of Dynamic Route Guidance Systems. Traffic Engineering and Control(33)327-329

  19. Trainer Interventions as Instructional Strategies in Air Traffic Control Training

    Science.gov (United States)

    Koskela, Inka; Palukka, Hannele

    2011-01-01

    Purpose: This paper aims to identify methods of guidance and supervision used in air traffic control training. It also aims to show how these methods facilitate trainee participation in core work activities. Design/methodology/approach: The paper applies the tools of conversation analysis and ethnomethodology to explore the ways in which trainers…

  20. Automatic speed control of highway traffic

    Science.gov (United States)

    Klingman, E. E.

    1973-01-01

    Vehicle control system monitors all vehicles in its range, and automatically slows down speeding vehicles by activating governor in vehicle. System determines only maximum speed; speeds below maximum are controlled by vehicle operator. Loss of transmitted signal or activation of emergency over-ride will open fuel line and return control to operator.

  1. Heavy traffic on a controlled motorway

    CERN Document Server

    Kelly, F P

    2010-01-01

    Unlimited access to a motorway network can, in overloaded conditions, cause a loss of capacity. Ramp metering (signals on slip roads to control access to the motorway) can help avoid this loss of capacity. The design of ramp metering strategies has several features in common with the design of access control mechanisms in communication networks. Inspired by models and rate control mechanisms developed for Internet congestion control, we propose a Brownian network model as an approximate model for a controlled motorway and consider it operating under a proportionally fair ramp metering policy.We present an analysis of the performance of this model.

  2. Constrained optimal steady-state control for isolated traffic intersections

    Institute of Scientific and Technical Information of China (English)

    Jack HADDAD; David MAHALEL; Ilya IOSLOVICH; Per-Olof GUTMAN

    2014-01-01

    The steady-state or cyclic control problem for a simplified isolated traffic intersection is considered. The optimization problem for the green-red switching sequence is formulated with the help of a discrete-event max-plus model. Two steady-state control problems are formulated: optimal steady-state with green duration constraints, and optimal steady-state control with lost time. In the case when the criterion is a strictly increasing, linear function of the queue lengths, the steady-state control problems can be solved analytically. The structure of constrained optimal steady-state traffic control is revealed, and the effect of the lost time on the optimal solution is illustrated.

  3. Urban Intersection Traffic Signal Control Based on Fuzzy Logic

    Institute of Scientific and Technical Information of China (English)

    魏武; 张毅; 张佐; 宋靖雁

    2002-01-01

    This paper presents a fuzzy logic adaptive traffic signal control method for an isolated four-approach intersection with through and left-turning movements. In the proposed method, the fuzzy logic controller can make adjustments to signal timing in response to observed changes. The "urgency degree" term that can describe different user's demands for a green light is used in the fuzzy logic decision-making. In addition, a three-level fuzzy controller model decides whether to extend or terminate the current signal phase and the sequence of phases. Simulation results show that the fuzzy controller can adjust its signal timing in response to changing traffic conditions on a real-time basis and that the proposed fuzzy logic controller leads to less vehicle delays and a lower percentage of stopped vehicles.

  4. Traffic Congestion Evaluation and Signal Control Optimization Based on Wireless Sensor Networks: Model and Algorithms

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    2012-01-01

    Full Text Available This paper presents the model and algorithms for traffic flow data monitoring and optimal traffic light control based on wireless sensor networks. Given the scenario that sensor nodes are sparsely deployed along the segments between signalized intersections, an analytical model is built using continuum traffic equation and develops the method to estimate traffic parameter with the scattered sensor data. Based on the traffic data and principle of traffic congestion formation, we introduce the congestion factor which can be used to evaluate the real-time traffic congestion status along the segment and to predict the subcritical state of traffic jams. The result is expected to support the timing phase optimization of traffic light control for the purpose of avoiding traffic congestion before its formation. We simulate the traffic monitoring based on the Mobile Century dataset and analyze the performance of traffic light control on VISSIM platform when congestion factor is introduced into the signal timing optimization model. The simulation result shows that this method can improve the spatial-temporal resolution of traffic data monitoring and evaluate traffic congestion status with high precision. It is helpful to remarkably alleviate urban traffic congestion and decrease the average traffic delays and maximum queue length.

  5. A New Approach to an Automated Air Traffic Control

    Institute of Scientific and Technical Information of China (English)

    Patchev Dragoljub

    2014-01-01

    This paper identifies areas of improvements of the air traffic control system and proposes modification of the concept of automation by using available technologies. With the proposed modification, the current Europe wide en route network structure can be modified in order to make routes more optimal. For this new route network structure, a new concept of automation will be used to manage with the air traffic. The first identified area of improvement is implementation of automation process that will enable decentralization of the air traffic control functionality to each individual aircraft and this will be achieved through automated routing of the aircrafts and CD&R (conflict detection and resolution). The FMS (flight management system) at the aircraft will make decisions for the optimal flight route based on the sensor inputs, information on selection of the routes, next hope points and flight levels, all received by ADS-B (automatic dependant surveillance-broadcast). The second area is processing the information about the deviation from the optimal route as in flight plan due to a traffic management (vectoring, level change) and taking it into consideration when further actions are undertaken. For each action, a cost factor will be calculated from the fuel burned for that action. This factor will be used to select conflict resolution protocol. The proposed concept shall increase the capacity of the network, and enable the air traff~c more efficient and more environmentally friendly while maintaining safe separation.

  6. 75 FR 74128 - Manual on Uniform Traffic Control Devices (MUTCD) Compliance Dates

    Science.gov (United States)

    2010-11-30

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF TRANSPORTATION Federal Highway Administration Manual on Uniform Traffic Control Devices (MUTCD) Compliance Dates AGENCY... control devices to comply with certain requirements established in the Manual on Uniform Traffic...

  7. Learning styles: The learning methods of air traffic control students

    Science.gov (United States)

    Jackson, Dontae L.

    In the world of aviation, air traffic controllers are an integral part in the overall level of safety that is provided. With a number of controllers reaching retirement age, the Air Traffic Collegiate Training Initiative (AT-CTI) was created to provide a stronger candidate pool. However, AT-CTI Instructors have found that a number of AT-CTI students are unable to memorize types of aircraft effectively. This study focused on the basic learning styles (auditory, visual, and kinesthetic) of students and created a teaching method to try to increase memorization in AT-CTI students. The participants were asked to take a questionnaire to determine their learning style. Upon knowing their learning styles, participants attended two classroom sessions. The participants were given a presentation in the first class, and divided into a control and experimental group for the second class. The control group was given the same presentation from the first classroom session while the experimental group had a group discussion and utilized Middle Tennessee State University's Air Traffic Control simulator to learn the aircraft types. Participants took a quiz and filled out a survey, which tested the new teaching method. An appropriate statistical analysis was applied to determine if there was a significant difference between the control and experimental groups. The results showed that even though the participants felt that the method increased their learning, there was no significant difference between the two groups.

  8. Betweenness centrality and its applications from modeling traffic flows to network community detection

    Science.gov (United States)

    Ren, Yihui

    As real-world complex networks are heterogeneous structures, not all their components such as nodes, edges and subgraphs carry the same role or importance in the functions performed by the networks: some elements are more critical than others. Understanding the roles of the components of a network is crucial for understanding the behavior of the network as a whole. One the most basic function of networks is transport; transport of vehicles/people, information, materials, forces, etc., and these quantities are transported along edges between source and destination nodes. For this reason, network path-based importance measures, also called centralities, play a crucial role in the understanding of the transport functions of the network and the network's structural and dynamical behavior in general. In this thesis we study the notion of betweenness centrality, which measures the fraction of lowest-cost (or shortest) paths running through a network component, in particular through a node or an edge. High betweenness centrality nodes/edges are those that will be frequently used by the entities transported through the network and thus they play a key role in the overall transport properties of the network. In the first part of the thesis we present a first-principles based method for traffic prediction using a cost-based generalization of the radiation model (emission/absorbtion model) for human mobility, coupled with a cost-minimizing algorithm for efficient distribution of the mobility fluxes through the network. Using US census and highway traffic data, we show that traffic can efficiently and accurately be computed from a range-limited, network betweenness type calculation. The model based on travel time costs captures the log-normal distribution of the traffic and attains a high Pearson correlation coefficient (0.75) when compared with real traffic. We then focus on studying the extent of changes in traffic flows in the wake of a localized damage or alteration to the

  9. TAF7: traffic controller in transcription initiation.

    Science.gov (United States)

    Gegonne, Anne; Devaiah, Ballachanda N; Singer, Dinah S

    2013-01-01

    TAF7, a component of the TFIID complex, controls the first steps of transcription. It interacts with and regulates the enzymatic activities of transcription factors that regulate RNA polymerase II progression. Its diverse functions in transcription initiation are consistent with its essential role in cell proliferation.

  10. A Control Method for Congested Traffic in the Car-Following Model

    Science.gov (United States)

    Ge, Hong-Xia; Yu, Jian; Lo, Siu-Ming

    2012-05-01

    A simple control method to suppress traffic congestion is proposed for the car-following model. The stability conditions are derived by using the control method, and the feedback signals, which act on our traffic system, are extended to the car-following model. The control signals will play an effect only if the traffic is congested. The corresponding numerical simulation results agree well with our theoretical analysis, and our control method can successfully suppress traffic jams.

  11. Urban Traffic Signal System Control Structural Optimization Based on Network Analysis

    Directory of Open Access Journals (Sweden)

    Li Wang

    2013-01-01

    Full Text Available Advanced urban traffic signal control systems such as SCOOT and SCATS normally coordinate traffic network using multilevel hierarchical control mechanism. In this mechanism, several key intersections will be selected from traffic signal network and the network will be divided into different control subareas. Traditionally, key intersection selection and control subareas division are executed according to dynamic traffic counts and link length between intersections, which largely rely on traffic engineers’ experience. However, it omits important inherent characteristics of traffic network topology. In this paper, we will apply network analysis approach into these two aspects for traffic system control structure optimization. Firstly, the modified C-means clustering algorithm will be proposed to assess the importance of intersections in traffic network and furthermore determine the key intersections based on three indexes instead of merely on traffic counts in traditional methods. Secondly, the improved network community discovery method will be used to give more reasonable evidence in traffic control subarea division. Finally, to test the effectiveness of network analysis approach, a hardware-in-loop simulation environment composed of regional traffic control system, microsimulation software and signal controller hardware, will be built. Both traditional method and proposed approach will be implemented on simulation test bed to evaluate traffic operation performance indexes, for example, travel time, stop times, delay and average vehicle speed. Simulation results show that the proposed network analysis approach can improve the traffic control system operation performance effectively.

  12. Controlling traffic jams by time modulating the safety distance

    Science.gov (United States)

    Gaididei, Yu. B.; Gorria, C.; Berkemer, R.; Kawamoto, A.; Shiga, T.; Christiansen, P. L.; Sørensen, M. P.; Starke, J.

    2013-10-01

    The possibility of controlling traffic dynamics by applying high-frequency time modulation of traffic flow parameters is studied. It is shown that the region of the car density where the uniform (free) flow is unstable changes in the presence of time modulation compared with the unmodulated case. This region shrinks when the speed-up of cars does not exceed some critical value and expands in the opposite case. The flux of the time-modulated flow is an increasing function of the amplitude of the modulation for traffic flows whose density is larger than 1/h where h is the safety distance in the nonmodulated case, while it is a decreasing function in the opposite case. In other words, the safety distance time modulation facilitates car propagation in the case when the mean distance between cars in the congestive traffic is less than h and hinders it when the neighboring cars in the flow are well separated. A link between a microscopic description and the macroscopic fundamental diagram is established.

  13. Human resources for the control of road traffic injury.

    Science.gov (United States)

    Mock, Charles; Kobusingye, Olive; Anh, Le Vu; Afukaar, Francis; Arreola-Risa, Carlos

    2005-04-01

    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 strategies, there is need for adequate institutional capacity, including funding, legal authority, and human resources. Several categories of human resources need to be developed: epidemiologists who can handle injury data, design surveillance systems, and undertake research; engineers and planners versed in safety aspects of road design, traffic flow, urban planning, and vehicle design; police and lawyers who understand the health impact of traffic law; clinicians who can develop cost-effective improvements in the entire system of trauma treatment; media experts to undertake effective behaviour change and social marketing; and economists to assist with cost-effectiveness evaluations. RTI control can be strengthened by enhancing such training in these disciplines, as well as encouraging retention of those who have the needed skills. Mechanisms to enhance collaboration between these different fields need to be promoted. Finally, the burden of RTI is borne disproportionately by the poor; in addition to technical issues, more profound equity issues must be addressed. This mandates that people from all professional backgrounds who work for RTI control should develop skills in advocacy and politics.

  14. Fuzzy Logic in Traffic Engineering: A Review on Signal Control

    Directory of Open Access Journals (Sweden)

    Milan Koukol

    2015-01-01

    Full Text Available Since 1965 when the fuzzy logic and fuzzy algebra were introduced by Lotfi Zadeh, the fuzzy theory successfully found its applications in the wide range of subject fields. This is mainly due to its ability to process various data, including vague or uncertain data, and provide results that are suitable for the decision making. This paper aims to provide comprehensive overview of literature on fuzzy control systems used for the management of the road traffic flow at road junctions. Several theoretical approaches from basic fuzzy models from the late 1970s to most recent combinations of real-time data with fuzzy inference system and genetic algorithms are mentioned and discussed throughout the paper. In most cases, fuzzy logic controllers provide considerable improvements in the efficiency of traffic junctions’ management.

  15. Occupational stress and stress prevention in air traffic control

    OpenAIRE

    Costa, Giovanni

    1996-01-01

    The paper indicates a number of preventive measures targeted to the elimination of the causes of stress, rather than the treatment of its effects, and how these measures can become an integral part of the necessary organizational development and eventually pay for themselves. The paper has seven chapters. 1. Introduction - What is stress? - The sources of stress in air traffic control - The consequences on health and well-being 2. How to prevent stress at work 3. Intervention on the external ...

  16. An Intelligent Traffic Flow Control System Based on Radio Frequency Identification and Wireless Sensor Networks

    OpenAIRE

    Chao, Kuei-Hsiang; Chen, Pi-Yun

    2014-01-01

    This study primarily focuses on the use of radio frequency identification (RFID) as a form of traffic flow detection, which transmits collected information related to traffic flow directly to a control system through an RS232 interface. At the same time, the sensor analyzes and judges the information using an extension algorithm designed to achieve the objective of controlling the flow of traffic. In addition, the traffic flow situation is also transmitted to a remote monitoring control syste...

  17. Cooperative Traffic Control based on the Artificial Bee Colony

    Directory of Open Access Journals (Sweden)

    Jinjian Li

    2016-12-01

    Full Text Available This paper studies the traffic control problem in an isolated intersection without traffic lights and phase, because the right-of-way is distributed to each vehicle individually based on connection of the Vehicle-to-Infrastructure (V2I, and the compatible streams are dynamically combined according to the arrival vehicles in each traffic flows. The control objective in the proposed algorithm is to minimize the time delay, which is defined as the difference between the travel time in real state and that in free flow state. In order to realize this target, a cooperative control structure with a two-way communications is proposed. First of all, once the vehicle enters the communication zone, it sends its information to the intersection. Then the passing sequence is optimized in the intersection with the heuristic algorithm of the Artificial Bee Colony, based on the arrival interval of the vehicles. At last, each vehicle plans its speed profile to meet the received passing sequence by V2I. The simulation results show that each vehicle can finish the entire travel trip with a near free flow speed in the proposed method.

  18. CONTROLLING TRAFFIC FLOW IN MULTILANE-ISOLATED INTERSECTION USING ANFIS APPROACH TECHNIQUES

    Directory of Open Access Journals (Sweden)

    G. R. LAI

    2015-08-01

    Full Text Available Many controllers have applied the Adaptive Neural-Fuzzy Inference System (ANFIS concept for optimizing the controller performance. However, there are less traffic signal controllers developed using the ANFIS concept. ANFIS traffic signal controller with its fuzzy rule base and its ability to learn from a set of sample data could improve the performance of Existing traffic signal controlling system to reduce traffic congestions at most of the busy traffic intersections in city such as Kuala Lumpur, Malaysia. The aim of this research is to develop an ANFIS traffic signals controller for multilane-isolated four approaches intersections in order to ease traffic congestions at traffic intersections. The new concept to generate sample data for ANFIS training is introduced in this research. The sample data is generated based on fuzzy rules and can be analysed using tree diagram. This controller is simulated on multilane-isolated traffic intersection model developed using M/M/1 queuing theory and its performance in terms of average waiting time, queue length and delay time are compared with traditional controllers and fuzzy controller. Simulation result shows that the average waiting time, queue length, and delay time of ANFIS traffic signal controller are the lowest as compared to the other three controllers. In conclusion, the efficiency and performance of ANFIS controller are much better than that of fuzzy and traditional controllers in different traffic volumes.

  19. Interaction Between Strategic and Local Traffic Flow Controls

    Science.gov (United States)

    Grabbe, Son; Sridhar, Banavar; Mukherjee, Avijit; Morando, Alexander

    2010-01-01

    The loosely coordinated sets of traffic flow management initiatives that are operationally implemented at the national- and local-levels have the potential to under, over, and inconsistently control flights. This study is designed to explore these interactions through fast-time simulations with an emphasis on identifying inequitable situations in which flights receive multiple uncoordinated delays. Two operationally derived scenarios were considered in which flights arriving into the Dallas/Fort Worth International Airport were first controlled at the national-level, either with a Ground Delay Program or a playbook reroute. These flights were subsequently controlled at the local level. The Traffic Management Advisor assigned them arrival scheduling delays. For the Ground Delay Program scenarios, between 51% and 53% of all arrivals experience both pre-departure delays from the Ground Delay Program and arrival scheduling delays from the Traffic Management Advisor. Of the subset of flights that received multiple delays, between 5.7% and 6.4% of the internal departures were first assigned a pre-departure delay by the Ground Delay Program, followed by a second pre-departure delay as a result of the arrival scheduling. For the playbook reroute scenario, Dallas/Fort Worth International Airport arrivals were first assigned pre-departure reroutes based on the MW_2_DALLAS playbook plan, and were subsequently assigned arrival scheduling delays by the Traffic Management Advisor. Since the airport was operating well below capacity when the playbook reroute was in effect, only 7% of the arrivals were observed to receive both rerouting and arrival scheduling delays. Findings from these initial experiments confirm field observations that Ground Delay Programs operated in conjunction with arrival scheduling can result in inequitable situations in which flights receive multiple uncoordinated delays.

  20. Controlled stochastic networks in heavy traffic: Convergence of value functions

    CERN Document Server

    Budhiraja, Amarjit; 10.1214/11-AAP784

    2012-01-01

    Scheduling control problems for a family of unitary networks under heavy traffic with general interarrival and service times, probabilistic routing and an infinite horizon discounted linear holding cost are studied. Diffusion control problems, that have been proposed as approximate models for the study of these critically loaded controlled stochastic networks, can be regarded as formal scaling limits of such stochastic systems. However, to date, a rigorous limit theory that justifies the use of such approximations for a general family of controlled networks has been lacking. It is shown that, under broad conditions, the value function of the suitably scaled network control problem converges to that of the associated diffusion control problem. This scaling limit result, in addition to giving a precise mathematical basis for the above approximation approach, suggests a general strategy for constructing near optimal controls for the physical stochastic networks by solving the associated diffusion control problem...

  1. The Use of the Dynamic Solution Space to Assess Air Traffic Controller Workload

    NARCIS (Netherlands)

    D'Engelbronner, J.G.; Mulder, M.; Van Paassen, M.M.; De Stigter, S.; Huisman, H.

    2010-01-01

    Air traffic capacity is mainly bound by air traffic controller workload. In order to effectively find solutions for this problem, off-line pre-experimental workload assessment methods are desirable. In order to better understand the workload associated with air traffic control, previous research int

  2. Analysis of Air Traffic Controller Workload Reduction Based on the Solution Space for the Merging Task

    NARCIS (Netherlands)

    Mercado Velasco, G.A.; Mulder, M.; Van Paassen, M.M.

    2010-01-01

    Air traffic controller workload is considered to be an important limiting factor to the growth of air traffic. The difficulty of an air traffic control task can be analyzed through examining the problem’s solution space, that is, all possible vector commands that satisfy the constraints of safety, p

  3. Traffic Control Plan : DeSoto National Wildlife Refuge, DeSoto Visitor Center

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Traffic Control Plan for DeSoto NWR outlines objectives for solving the traffic problems on the Refuge by implementing a patrol schedule, restricting visitor...

  4. A Traffic Prediction Algorithm for Street Lighting Control Efficiency

    Directory of Open Access Journals (Sweden)

    POPA Valentin

    2013-01-01

    Full Text Available This paper presents the development of a traffic prediction algorithm that can be integrated in a street lighting monitoring and control system. The prediction algorithm must enable the reduction of energy costs and improve energy efficiency by decreasing the light intensity depending on the traffic level. The algorithm analyses and processes the information received at the command center based on the traffic level at different moments. The data is collected by means of the Doppler vehicle detection sensors integrated within the system. Thus, two methods are used for the implementation of the algorithm: a neural network and a k-NN (k-Nearest Neighbor prediction algorithm. For 500 training cycles, the mean square error of the neural network is 9.766 and for 500.000 training cycles the error amounts to 0.877. In case of the k-NN algorithm the error increases from 8.24 for k=5 to 12.27 for a number of 50 neighbors. In terms of a root means square error parameter, the use of a neural network ensures the highest performance level and can be integrated in a street lighting control system.

  5. Efficient Traffic Control of VoD System

    CERN Document Server

    Kanrar, Soumen

    2011-01-01

    It has been a challenging issue to provide digital quality multimedia data stream to the remote user through the distributed system. The main aspects to design the real distributed system, which reduce the cost of the network by means of reduce packet loss and enhanced over all system performance. Since the number of user increased rapidly in the network it posed heavy load to the video servers. The requested clients, servers are all distributed in nature and the data stream delivered to the user without error. In this work I have presented the performance of the video on demand server by efficient traffic control at real time with respect to incoming multirate traffic pattern . In this work, I present how the overall system performance gradually decreases when the client population sized in the clusters increase. This work indicated the load balancing required for the on demand video distributed system to provide efficient cost effective service to the local or remote clients.

  6. Controlling centrality in complex networks

    CERN Document Server

    Nicosia, Vincenzo; Romance, Miguel; Russo, Giovanni; Latora, Vito

    2011-01-01

    Spectral centrality measures allow to identify influential individuals in social groups, to rank Web pages by their popularity, and even to determine the impact of scientific researches. The centrality score of a node within a network crucially depends on the entire pattern of connections, so that the usual approach is to compute the node centralities once the network structure is assigned. We face here with the inverse problem, that is, we study how to modify the centrality scores of the nodes by acting on the structure of a given network. We prove that there exist particular subsets of nodes, called controlling sets, which can assign any prescribed set of centrality values to all the nodes of a graph, by cooperatively tuning the weights of their out-going links. We show that many large networks from the real world have surprisingly small controlling sets, containing even less than 5-10% of the nodes. These results suggest that rankings obtained from spectral centrality measures have to be considered with ex...

  7. Delay-feedback control strategy for reducing CO2 emission of traffic flow system

    Science.gov (United States)

    Zhang, Li-Dong; Zhu, Wen-Xing

    2015-06-01

    To study the signal control strategy for reducing traffic emission theoretically, we first presented a kind of discrete traffic flow model with relative speed term based on traditional coupled map car-following model. In the model, the relative speed difference between two successive running cars is incorporated into following vehicle's acceleration running equation. Then we analyzed its stability condition with discrete control system stability theory. Third, we designed a delay-feedback controller to suppress traffic jam and decrease traffic emission based on modern controller theory. Last, numerical simulations are made to support our theoretical results, including the comparison of models' stability analysis, the influence of model type and signal control on CO2 emissions. The results show that the temporal behavior of our model is superior to other models, and the traffic signal controller has good effect on traffic jam suppression and traffic CO2 emission, which fully supports the theoretical conclusions.

  8. Performance Evaluation of Road Traffic Control Using a Fuzzy Cellular Model

    CERN Document Server

    Płaczek, Bartłomiej

    2011-01-01

    In this paper a method is proposed for performance evaluation of road traffic control systems. The method is designed to be implemented in an on-line simulation environment, which enables optimisation of adaptive traffic control strategies. Performance measures are computed using a fuzzy cellular traffic model, formulated as a hybrid system combining cellular automata and fuzzy calculus. Experimental results show that the introduced method allows the performance to be evaluated using imprecise traffic measurements. Moreover, the fuzzy definitions of performance measures are convenient for uncertainty determination in traffic control decisions.

  9. Traffic Signals Control with Adaptive Fuzzy Controller in Urban Road Network

    Institute of Scientific and Technical Information of China (English)

    LI Yan; FAN Xiao-ping

    2008-01-01

    An adaptive fuzzy logic controller (AFC) is presented for the signal control of the urban traffic network.The AFC is composed of the signal control system-oriented control level and the signal controller-oriented fuzzy rules regulation level.The control level decides the signal tunings in an intersection with a fuzzy logic controller.The regulation level optimizes the fuzzy rules by the Adaptive Rule Module in AFC according to both the system performance index in current control period and the traffic flows in the last one.Consequently the system performances are improved.A weight coefficient controller (WCC) is also developed to describe the interactions of traffic flow among the adjacent intersections.So the AFC combined with the WCC can be applied in a road network for signal timings.Simulations of the AFC on a real traffic scenario have been conducted.Simulation results indicate that the adaptive controller for traffic control shows better performance than the actuated one.

  10. A Traffic Reduction Method for Centralized RSSI-Based Location Estimation in Wireless Sensor Networks

    Science.gov (United States)

    Zemek, Radim; Hara, Shinsuke; Yanagihara, Kentaro; Kitayama, Ken-Ichi

    In a centralized localization scenario, the limited throughput of the central node constrains the possible number of target node locations that can be estimated simultaneously. To overcome this limitation, we propose a method which effectively decreases the traffic load associated with target node localization, and therefore increases the possible number of target node locations that can estimated simultaneously in a localization system based on received signal strength indicator (RSSI) and maximum likelihood estimation. Our proposed method utilizes a threshold which limits the amount of forwarded RSSI data to the central node. As the threshold is crucial to the method, we further propose a method to theoretically determine its value. We experimentally verified the proposed method in various environments and the experimental results revealed that the method can reduce the load by 32-64% without significantly affecting the estimation accuracy.

  11. Adaptive Traffic Control Systems in a medium-sized Scandinavian city

    DEFF Research Database (Denmark)

    Agerholm, Niels; Olesen, Anne Vingaard

    2017-01-01

    Adaptive Traffic Control Systems (ATCS) are aimed at reducing congestion. ATCS adapt to approaching traffic to continuously optimise the traffic flows in question. ATCS have been implemented in many locations, including the Scandinavian countries, with various effects. Due to congestion problems...

  12. Analysis of routine communication in the air traffic control system

    Science.gov (United States)

    Clark, Herbert H.; Morrow, Daniel; Rodvoid, Michelle

    1990-01-01

    The present project has three related goals. The first is to describe the organization of routine controller-pilot communication. This includes identifying the basic units of communication and how they are organized into discourse, how controllers and pilots use language to achieve their goals, and what topics they discuss. The second goal is to identify the type and frequency of problems that interrupt routine information transfer and prompt pilots and controllers to focus on the communication itself. The authors analyze the costs of these problems in terms of communication efficiency, and the techniques used to resolve these problems. Third, the authors hope to identify factors associated with communication problems, such as deviations from conventional air traffic control procedures.

  13. An augmented reality binocular system (ARBS) for air traffic controllers

    Science.gov (United States)

    Fulbrook, Jim E.; Ruffner, John W.; Labbe, Roger

    2008-04-01

    The primary means by which air traffic tower controllers obtain information is through direct out-thewindow viewing, although a considerable amount of time is spent looking at electronic displays and other information sources inside the tower cab. The Air Force Research Laboratory sponsored the development of a prototype Augmented Reality Binocular System (ARBS) that enhances tower controller performance, situation awareness, and safety. The ARBS is composed of a virtual binocular (VB) that displays real-time imagery from high resolution telephoto cameras and sensors mounted on pan/tilt units (PTUs). The selected PTU tracks to the movement of the VB, which has an inertial heading and elevation sensor. Relevant airfield situation text and graphic depictions that identify airfield features are overlaid on the imagery. In addition, the display is capable of labeling and tracking vehicles on which an Automatic Dependent Surveillance - Broadcast (ADS-B) system has been installed. The ARBS provides air traffic controllers and airfield security forces with the capability to orient toward, observe, and conduct continuous airfield operations and surveillance/security missions from any number of viewing aspects in limited visibility conditions. In this paper, we describe the ARBS in detail, discuss the results of a Usability Test of the prototype ARBS, and discuss ideas for follow-on efforts to develop the ARBS to a fieldable level.

  14. Admission control with long-range dependence traffic input

    Institute of Scientific and Technical Information of China (English)

    RAO Yun-hua; ZOU Xue-cheng

    2005-01-01

    The admission control scheme is investigated for a FIFO self-similar queuing system with Quality of Service (QoS) performance guarantees. Since the self-similar queuing system performance analysis is often carried out under the condition of infinite buffer, it is difficult to deduce the upper boundary of buffer overflow probability. To overcome this shortcoming, a simple overflow condition is proposed, which defines a buffer overflow occurrence whenever the arrival rate exceeds the service rate. The analytic formula for the buffer overflow probability upper boundary is easily obtained under this condition. The required bandwidth upper boundary with long-range dependence input and determined overflow probability is then derived from this formula. Based on the above analytic formulas, the upper boundaries of the admission control regions for homogeneous and heterogeneous long-range dependence traffic sources are separately obtained. Finally, an effective admission control scheme for long-range dependence input is proposed. Simulation studies with real traffic have confirmed the validity of these results.

  15. Cellular Automaton Models of Highway Traffic Flow Considering Lane-Control and Speed-Control

    Institute of Scientific and Technical Information of China (English)

    钱勇生; 李文俊; 曾俊伟; 王敏; 杜加伟; 广晓平

    2011-01-01

    As two kinds of management modes of highway tramc control, lane-control, and speed-control produce different effect under different conditions. In this paper, traffic flow cellular automaton models for four-lane highway system with two opposing directions under the above two modes are established considering car and truck mixed running. Through computer numerical simulating, the fundamental diagrams with different parameters are obtained, and after the analysis of density-flux diagrams, the variation discipline of flux with traffic density under different control models is gained. The results indicate that, compared with lane-control, utilization ratio of road can be further improved with speed-control when the truck number increases. The research result is of great significance for reasonable providing theoretical guidance for highway traffic control.

  16. A Cooperative Traffic Control of Vehicle–Intersection (CTCVI) for the Reduction of Traffic Delays and Fuel Consumption

    Science.gov (United States)

    Li, Jinjian; Dridi, Mahjoub; El-Moudni, Abdellah

    2016-01-01

    The problem of reducing traffic delays and decreasing fuel consumption simultaneously in a network of intersections without traffic lights is solved by a cooperative traffic control algorithm, where the cooperation is executed based on the connection of Vehicle-to-Infrastructure (V2I). This resolution of the problem contains two main steps. The first step concerns the itinerary of which intersections are chosen by vehicles to arrive at their destination from their starting point. Based on the principle of minimal travel distance, each vehicle chooses its itinerary dynamically based on the traffic loads in the adjacent intersections. The second step is related to the following proposed cooperative procedures to allow vehicles to pass through each intersection rapidly and economically: on one hand, according to the real-time information sent by vehicles via V2I in the edge of the communication zone, each intersection applies Dynamic Programming (DP) to cooperatively optimize the vehicle passing sequence with minimal traffic delays so that the vehicles may rapidly pass the intersection under the relevant safety constraints; on the other hand, after receiving this sequence, each vehicle finds the optimal speed profiles with the minimal fuel consumption by an exhaustive search. The simulation results reveal that the proposed algorithm can significantly reduce both travel delays and fuel consumption compared with other papers under different traffic volumes. PMID:27999333

  17. 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)

  18. Trajectory Specification for Automation of Terminal Air Traffic Control

    Science.gov (United States)

    Paielli, Russell A.

    2016-01-01

    "Trajectory specification" is the explicit bounding and control of aircraft tra- jectories such that the position at each point in time is constrained to a precisely defined volume of space. The bounding space is defined by cross-track, along-track, and vertical tolerances relative to a reference trajectory that specifies position as a function of time. The tolerances are dynamic and will be based on the aircraft nav- igation capabilities and the current traffic situation. A standard language will be developed to represent these specifications and to communicate them by datalink. Assuming conformance, trajectory specification can guarantee safe separation for an arbitrary period of time even in the event of an air traffic control (ATC) sys- tem or datalink failure, hence it can help to achieve the high level of safety and reliability needed for ATC automation. As a more proactive form of ATC, it can also maximize airspace capacity and reduce the reliance on tactical backup systems during normal operation. It applies to both enroute airspace and the terminal area around airports, but this paper focuses on arrival spacing in the terminal area and presents ATC algorithms and software for achieving a specified delay of runway arrival time.

  19. Traffic management and control in intelligent vehicle highway systems

    NARCIS (Netherlands)

    Baskar, L.D.

    2009-01-01

    Traffic congestion is a problem experienced daily by most of us. Among various traffic management schemes, efficient utilisation of the existing roadside infrastructure combined with in-vehicle technologies offers a promising solution to address traffic congestion and related problems. This approach

  20. Step-coordination Algorithm of Traffic Control Based on Multi-agent System

    Institute of Scientific and Technical Information of China (English)

    Hai-Tao Zhang; Fang Yu; Wen Li

    2009-01-01

    Aiming at the deficiency of conventional traffic control method, this paper proposes a new method based on multi-agent technology for traffic control. Different from many existing methods, this paper distinguishes traffic control on the basis of the agent technology from conventional traffic control method. The composition and structure of a multi-agent system (MAS) is first discussed. Then, the step-coordination strategies of intersection-agent, segment-agent, and area-agent are put forward. The advantages of the algorithm are demonstrated by a simulation study.

  1. Lattice hydrodynamic model based traffic control: A transportation cyber-physical system approach

    Science.gov (United States)

    Liu, Hui; Sun, Dihua; Liu, Weining

    2016-11-01

    Lattice hydrodynamic model is a typical continuum traffic flow model, which describes the jamming transition of traffic flow properly. Previous studies in lattice hydrodynamic model have shown that the use of control method has the potential to improve traffic conditions. In this paper, a new control method is applied in lattice hydrodynamic model from a transportation cyber-physical system approach, in which only one lattice site needs to be controlled in this control scheme. The simulation verifies the feasibility and validity of this method, which can ensure the efficient and smooth operation of the traffic flow.

  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. Flight management concepts compatible with air traffic control

    Science.gov (United States)

    Morello, S. A.

    1986-01-01

    With the advent of airline deregulation and increased competition, the need for cost efficient airline operations is critical. This paper summarizes past research efforts and planned research thrusts toward the development of compatible flight management and air traffic control systems that promise increased operational effectiveness and efficiency. Potential capacity improvements resulting from a time-based ATC simulation (fast-time) are presented. Advanced display concepts with time guidance and velocity vector information to allow the flight crew to play an important role in the future ATC environment are discussed. Results of parametric sensitivity analyses are also presented that quantify the fuel/cost penalties for idle-thrust mismodeling and wind-modeling errors.

  4. Self-control of traffic lights and vehicle flows in urban road networks

    Science.gov (United States)

    Lämmer, Stefan; Helbing, Dirk

    2008-04-01

    Based on fluid-dynamic and many-particle (car-following) simulations of traffic flows in (urban) networks, we study the problem of coordinating incompatible traffic flows at intersections. Inspired by the observation of self-organized oscillations of pedestrian flows at bottlenecks, we propose a self-organization approach to traffic light control. The problem can be treated as a multi-agent problem with interactions between vehicles and traffic lights. Specifically, our approach assumes a priority-based control of traffic lights by the vehicle flows themselves, taking into account short-sighted anticipation of vehicle flows and platoons. The considered local interactions lead to emergent coordination patterns such as 'green waves' and achieve an efficient, decentralized traffic light control. While the proposed self-control adapts flexibly to local flow conditions and often leads to non-cyclical switching patterns with changing service sequences of different traffic flows, an almost periodic service may evolve under certain conditions and suggests the existence of a spontaneous synchronization of traffic lights despite the varying delays due to variable vehicle queues and travel times. The self-organized traffic light control is based on an optimization and a stabilization rule, each of which performs poorly at high utilizations of the road network, while their proper combination reaches a superior performance. The result is a considerable reduction not only in the average travel times, but also of their variation. Similar control approaches could be applied to the coordination of logistic and production processes.

  5. The Conception Approach to the Traffic Control in Czech Cities - Examples from Prague

    Science.gov (United States)

    Tichý, Tomáš; Krajčír, Dušan

    Modern and economic development of contemporary towns is without question highly dependent upon traffic infrastructure progress. Automobile transport intensity is dramatically rising in large towns and other Czech and European cities. At the same time number of traffic congestions and accidents is increasing, standing times are becoming longer and ecological stress is also escalated. To solve this situation seems to be the most effective solution to design intelligent traffic light intersection control system, variable message signs, preference of public transportation, road line traffic control and next telematics subsystems. This control system and subsystems should improve permeability of traffic road network with a respect for all demands on recent trends of traffic development in towns and regions.

  6. Comprehensive Optimization of Emergency Evacuation Route and Departure Time under Traffic Control

    Directory of Open Access Journals (Sweden)

    Guo Li

    2014-01-01

    Full Text Available With the frequent occurrence of major emergencies, emergency management gets high attention from all around the world. This paper investigates the comprehensive optimization of major emergency evacuation route and departure time, in which case the evacuation propagation mechanism is considered under traffic control. Given the practical assumptions, we first establish a comprehensive optimization model based on the simulation of evacuation route and departure time. Furthermore, we explore the reasonable description method of evacuation traffic flow propagation under traffic control, including the establishment of traffic flow propagation model and the design of the simulation mudule that can simulate the evacuation traffic flow. Finally, we propose a heuristic algorithm for the optimization of this comprehensive model. In case analysis, we take some areas in Beijing as the evaluation sources to verify the reliability of our model. A series of constructive suggestions for Beijing's emergency evacuation are proposed, which can be applied to the actual situation under traffic control.

  7. Mobile Phone Based RIMS for Traffic Control a Case Study of Tanzania

    Directory of Open Access Journals (Sweden)

    Angela-Aida Karugila Runyoro

    2015-04-01

    Full Text Available Vehicles saturation in transportation infrastructure causes traffic congestion, accidents, transportation delays and environment pollution. This problem can be resolved with proper management of traffic flow. Existing traffic management systems are challenged on capturing and processing real-time road data from wide area road networks. The main purpose of this study is to address the gap by implementing a mobile phone based Road Information Management System. The proposed system integrates three modules for data collection, storage and information dissemination. The modules works together to enable real-time traffic control. Disseminated information from the system, enables road users to adjust their travelling habit, also it allows the traffic lights to control the traffic in relation to the real-time situation occurring on the road. In this paper the system implementation and testing was performed. The results indicated that there is a possibility to track traffic data using Global Positioning System enabled mobile phones, and after processing the collected data, real-time traffic status was displayed on web interface. This enabled road users to know in advance the situation occurring on the roads and hence make proper travelling decision. Further research should consider adjusting the traffic lights control system to understand the disseminated real-time traffic information.

  8. Traffic Accident Propagation Properties and Control Measures for Urban Links Based on Cellular Automata

    Directory of Open Access Journals (Sweden)

    Xian-sheng Li

    2013-01-01

    Full Text Available With the rapid development of urban transport and the sharp increase in vehicle population, traffic accidents form one of the most important causes of urban traffic congestion other than the imbalance between traffic supply and demand. Traffic congestion causes severe problems, such as environment contamination and energy dissipation. Therefore, it would be useful to analyze the congestion propagation characteristics after traffic accidents. Numerical analysis and computer simulation were two of the typical methods used at present to study the traffic congestion propagation properties. The latter was more widespread as it is more consistent with the actual traffic flow and more visual than the former. In this paper, an improved cellular automata (CA model was presented to analyze traffic congestion propagation properties and to evaluate control strategies. In order to apply them to urban traffic flow simulation, the CA models have been improved and expanded on. Computer simulations were built for congestion not only extending to the upstream intersection, but also the upstream intersection and the entire road network, respectively. Congestion propagation characteristics after road traffic accidents were obtained, and controls of different severities and durations were analyzed. The results provide the theoretical foundation and practical means for the control of congestion.

  9. 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...... shown, although many studies have shown extravasation of activated or memory T cells. We have used a novel experimental system to track naive T cells to the central nervous system (CNS) in TCR transgenic mice with adoptively transferred experimental autoimmune encephalomyelitis. Ovalbumin (OVA)-specific...... CD4(+) T cells were equivalent in number to disease-inducing myelin basic protein (MBP)-specific T cells at disease onset. Furthermore, OVA-specific T cells retained a naive phenotype and did not transcribe Th1 cytokines, in contrast to MBP-specific T cells. These findings demonstrate that the T cell...

  10. Dimensions of Air Traffic Control Tower Information Needs: From Information Requests to Display Design

    Science.gov (United States)

    Durso, Francis T.; Johnson, Brian R.; Crutchfield, Jerry M.

    2010-01-01

    In an effort to determine the information needs of tower air traffic controllers, instructors from the Federal Aviation Administration's Academy in Oklahoma City were asked to control traffic in a high-fidelity tower cab simulator. Information requests were made apparent by eliminating access to standard tower information sources. Instead,…

  11. Analysis of learning curves in the on-the-job training of air traffic controllers

    NARCIS (Netherlands)

    Oprins, E.A.P.B.; Bruggraaff, E.; Roe, R.

    2011-01-01

    This chapter describes a competence-based assessment system, called CBAS, for air traffic control (ATC) simulator and on-the-job training (OJT), developed at Air Traffic Control The Netherlands (LVNL). In contrast with simulator training, learning processes in OJT are difficult to assess, because th

  12. Effects of Stereoscopic 3D Digital Radar Displays on Air Traffic Controller Performance

    Science.gov (United States)

    2013-03-01

    Effects of Stereoscopic 3D Digital Radar Displays on Air Traffic Controller Performance THESIS...and is not subject to copyright protection in the United States. AFIT-ENV-13-M-24 Effects of Stereoscopic 3D Digital Radar Displays on Air... Stereoscopic 3D Digital Radar Displays on Air Traffic Controller Performance Jason G. Russi Technical Sergeant, USAF Approved

  13. Effects of speed bottleneck on traffic flow with feedback control signal

    Science.gov (United States)

    Zhu, Kangli; Bi, Jiantao; Wu, Jianjun; Li, Shubin

    2016-09-01

    Various car-following models (CMs) have been developed to capture the complex characteristics of microscopic traffic flow, among which the coupled map CM can better reveal and reflect various phenomena of practical traffic flow. Capacity change at bottleneck contributes to high-density traffic flow upstream the bottleneck and contains very complex dynamic behavior. In this paper, we analyze the effect of speed bottleneck on the spatial-temporal evolution characteristics of traffic flow, and propose a method to reduce traffic congestion with the feedback control signal based on CM. Simulation results highlight the potential of using the feedback signal to control the stop-and-go wave and furthermore to alleviate the traffic congestion effectively.

  14. EVALUATION OF A DYNAMIC SIGNAL OPTIMISATION CONTROL MODEL USING TRAFFIC SIMULATION

    Directory of Open Access Journals (Sweden)

    Suphasawas NIGARNJANAGOOL

    2005-01-01

    Full Text Available The objective of this paper is to demonstrate the feasibility of implementing a traffic signal optimisation model to improve real-time operations of traffic control systems. Advanced computer algorithms and traffic optimisation techniques can provide benefits over existing systems by reducing delays, improving travel times and reducing environmental emissions. The feasibility of the proposed approach is demonstrated by interfacing the traffic signal optimisation model to a microscopic traffic simulation tool, which enabled the evaluation of the benefits of the algorithm using computers in a controlled environment without disrupting traffic conditions. The main advantage of the proposed algorithm is its ability to detect dynamic changes in traffic flow conditions by using short-term historical demand data obtained from upstream vehicle loop detectors. The experimental results for under-saturated traffic conditions showed that the algorithm's performance was superior to optimal fixed time control. The results also confirmed that as traffic volumes reach saturated conditions, the performance of the algorithm decreased but remained better than what can be achieved by fixed time control systems.

  15. A Survey of Modern Air Traffic Control. Volume 2

    Science.gov (United States)

    1975-07-01

    oceanic traffic would use combined hyperbolic-inertial navigation systems. System I could be implemented to meet the demanda for air traffic services...of Aviation c/o Flugrad Reykjavik ITALY Aeronautica Militare Ufficio del Delegato Nationale all’AGARD 3, Piazzale Adenauer Roma /EUR

  16. Vehicle-class Specific Control of Freeway Traffic

    NARCIS (Netherlands)

    Schreiter, T.

    2013-01-01

    The increase of mobility of the past decades has led to substantial congestion on the freeways. Traffic jams emerge both on a daily basis at the same location, as well as during accidents when a part of the freeways is temporarily blocked. In those cases, traffic management centers intervene into tr

  17. Traffic Flow at Sags: Theory, Modeling and Control

    NARCIS (Netherlands)

    Goni-Ros, B.

    2016-01-01

    Sag vertical curves (sags) are roadway sections along which the gradient increases gradually in the direction of traffic. Empirical observations show that, on freeways, traffic congestion often occurs at sags; actually, in some countries (e.g., Japan), sags are one of the most common types of freewa

  18. Traffic control and intelligent vehicle highway systems: a survey

    NARCIS (Netherlands)

    Baskar, L.D.; Schutter, B. de; Hellendoorn, J.; Papp, Z.

    2011-01-01

    Traffic congestion in highway networks is one of the main issues to be addressed by today's traffic management schemes. Automation combined with the increasing market penetration of on-line communication, navigation and advanced driver assistance systems will ultimately result in intelligent vehicle

  19. Automation and Systems Issues in Air Traffic Control

    Directory of Open Access Journals (Sweden)

    Gabriela STROE

    2016-12-01

    Full Text Available This paper is dedicated to the study and analysis of a successfully designed control system in ATM. The aircraft's motion is affected by other factors, besides the pilot controls in the form of external disturbances, such as wind, and internal errors, due to unmodelled dynamics, tracking error and system noise. Navigation equipment tracks the exact real-time location of the aircraft in 4D space and provides feedback to both the pilot in the cockpit and ATC via ADS-B. ATM was expressed as a large, decentralized, dynamic, variable size, infinite horizon, multi-parameter, constrained, nonlinear, non-causal, non-convex, multi-objective, high-dimensionality, hybrid (continuous and combinatorial, optimal control problem. Rapidly increasing growth and demand in CNS/ATM, the advanced scheme for ATM, ADS-B system which is based on digital communication is being implemented in the field of surveillance. ADS-B is a radically new technology that is redefining the paradigm of CNS in ATM today. Automatic Dependent Surveillance-Broadcast (ADS-B is the next generation air surveillance system which supplants and complements the limitations of conventional radar, since conventional ATM radar systems will reach their limits soon due to the increases in air traffic.

  20. Control of Future Air Traffic Systems via Complexity Bound Management

    Science.gov (United States)

    Alexandrov, Natalia

    2013-01-01

    The complexity of the present system for managing air traffic has led to "discreteness" in approaches to creating new concepts: new concepts are created as point designs, based on experience, expertise, and creativity of the proposer. Discrete point designs may be highly successful but they are difficult to substantiate in the face of equally strong substantiation of competing concepts, as well as the state of the art in concept evaluation via simulations. Hybrid concepts may present a compromise - the golden middle. Yet a hybrid of sometimes in principle incompatible concepts forms another point design that faces the challenge of substantiation and validation. We are faced with the need to re-design the air transportation system ab initio. This is a daunting task, especially considering the problem of transitioning from the present system to any fundamentally new system. However, design from scratch is also an opportunity to reconsider approaches to new concept development. In this position paper we propose an approach, Optimized Parametric Functional Design, for systematic development of concepts for management and control of airspace systems, based on optimization formulations in terms of required system functions and states. This reasoning framework, realizable in the context of ab initio system design, offers an approach to deriving substantiated airspace management and control concepts. With growing computational power, we hope that the approach will also yield a methodology for actual dynamic control of airspace

  1. Soil, crop and emission responses to seasonal-controlled traffic in organic vegetable farming on loam soil

    NARCIS (Netherlands)

    Vermeulen, G.D.; Mosquera Losada, J.

    2009-01-01

    Some organic arable and vegetable farms in the Netherlands use cm-precise guidance of machinery to restrict wheel traffic to fixed traffic lanes and to achieve non-trafficked cropping zones with optimized soil structure in between the lanes. Contrary to controlled traffic farming (CTF) the traffic l

  2. Design and Construction of Intelligent Traffic Light Control System Using Fuzzy Logic

    Science.gov (United States)

    Lin, Htin; Aye, Khin Muyar; Tun, Hla Myo; Theingi, Naing, Zaw Min

    2008-10-01

    Vehicular travel is increasing throughout the world, particularly in large urban areas. Therefore the need arises for simulation and optimizing traffic control algorithms to better accommodate this increasing demand. This paper presents a microcontroller simulation of intelligent traffic light controller using fuzzy logic that is used to change the traffic signal cycles adaptively at a two-way intersection. This paper is an attempt to design an intelligent traffic light control systems using microcontrollers such as PIC 16F84A and PIC 16F877A. And then traffic signal can be controlled depending upon the densities of cars behind green and red lights of the two-way intersection by using sensors and detectors circuits.

  3. TASAR Flight Trial 2: Assessment of Air Traffic Controller Acceptability of TASAR Requests

    Science.gov (United States)

    Idris, Husni; Enea, Gabriele

    2016-01-01

    In support of the Flight Trial (FT-2) of NASA's prototype of the Traffic Aware Strategic Aircrew Requests (TASAR) concept, observations were conducted at the air traffic facilities to identify and assess the main factors that affect the acceptability of pilot requests by air traffic controllers. Two observers shadowed air traffic controllers at the Atlanta (ZTL) and Jacksonville (ZJX) air traffic control centers as the test flight pilot made pre-scripted requests to invoke acceptability issues and then they interviewed the observed and other controllers voluntarily. Fifty controllers were interviewed with experience ranging from one to thirty-five years. All interviewed controllers were enthusiastic about the technology and accounting for sector boundaries in pilot requests, particularly if pilots can be made aware of high workload situations. All interviewed controllers accept more than fifty percent of pilot requests; forty percent of them reject less than ten percent of requests. The most common reason for rejecting requests is conflicting with traffic followed by violating letters of agreement (LOAs) and negatively impacting neighboring sector workload, major arrival and departure flows and flow restrictions. Thirty-six requests were made during the test, eight of which were rejected due to: the aircraft already handed off to another sector, violating LOA, opposing traffic, intruding into an active special use airspace (SUA), intruding into another center, weather, and unfamiliarity with the requested waypoint. Nine requests were accepted with delay mostly because the controller needed to locate unfamiliar waypoints or to coordinate with other controllers.

  4. Feedback control scheme of traffic jams based on the coupled map car-following model

    Science.gov (United States)

    Zhou, Tong; Sun, Di-Hua; Zhao, Min; Li, Hua-Min

    2013-09-01

    Based on the pioneering work of Konishi et al. [Phys. Rev. E (1999) 60 4000], a new feedback control scheme is presented to suppress traffic jams based on the coupled map car-following model under the open boundary condition. The effect of the safe headway on the traffic system is considered. According to the control theory, the condition under which traffic jams can be suppressed is analyzed. The results are compared with the previous results concerning congestion control. The simulations show that the suppression performance of our scheme on traffic jams is better than those of the previous schemes, although all the schemes can suppress traffic jams. The simulation results are consistent with theoretical analyses.

  5. Computer-Aided Air-Traffic Control In The Terminal Area

    Science.gov (United States)

    Erzberger, Heinz

    1995-01-01

    Developmental computer-aided system for automated management and control of arrival traffic at large airport includes three integrated subsystems. One subsystem, called Traffic Management Advisor, another subsystem, called Descent Advisor, and third subsystem, called Final Approach Spacing Tool. Data base that includes current wind measurements and mathematical models of performances of types of aircraft contributes to effective operation of system.

  6. Potential of controlled traffic farming with automatic guidance on an organic farm in the Netherlands

    NARCIS (Netherlands)

    Vermeulen, G.D.; Mosquera, J.; Wel, van der C.; Klooster, van der A.; Steenhuizen, J.W.

    2007-01-01

    Some organic farms in the Netherlands use RTK-DGPS guidance of machinery over fixed traffic lanes to achieve non-trafficked cropping zones with optimum soil structure. These lanes are not yet used for harvesting and primary tillage. The potential of such a seasonal controlled traffic farming (SCTF)

  7. Traffic flow impacts of adaptive cruise control deactivation and (Re)activation with cooperative driver behavior

    NARCIS (Netherlands)

    Klunder, G.; Li, M.; Minderhoud, M.

    2009-01-01

    In 2006 in the Netherlands, a field operational test was carried out to study the effect of adaptive cruise control (ACC) and lane departure warning on driver behavior and traffic flow in real traffic. To estimate the effect for larger penetration rates, simulations were needed. For a reliable impac

  8. Solution Space-based Approach to Assess Sector Complexity in Air Traffic Control

    NARCIS (Netherlands)

    Abdul Rahman, S.M.B.

    2014-01-01

    Various methods have been introduced in the past in efforts to optimize airspace sector design and the allocation of air traffic controllers. This is done with the aim to accommodate growth, increase productivity and most importantly to ensure safety of air traffic. To accomplish this, a more compre

  9. Scheduling with conflicts, and applications to traffic signal control

    Energy Technology Data Exchange (ETDEWEB)

    Irani, S.; Leung, V. [Univ. of California, Irvine, CA (United States)

    1996-12-31

    In this paper, we consider the scheduling of jobs that may be competing for mutually exclusive resources. We model the conflicts between jobs with a conflict graph, so that all concurrently running jobs must form an independent set in the graph. We believe that this model is natural and general enough to have applications in a variety of settings; however, we are motivated by the following two specific applications: traffic intersection control and session scheduling in high speed local area networks with spatial reuse. In both of these applications, guaranteeing the best turnaround time to any job entering the system is important. Our results focus on two special classes of graphs motivated by our applications: bipartite graphs and interval graphs. Although the algorithms for bipartite and intervals graphs are quite different, the bounds they achieve are the same: we prove that for any sequence of jobs in which the maximum completion time of a job in the optimal schedule is bounded by A, the algorithm can complete every job in time O(n{sup 3} A{sup 2}). n is the number of nodes in the conflict graph. We also show that the best competitive ratio achievable by any online algorithm for the maximum completion time on interval or bipartite graphs is {Omega}(n).

  10. The influence of automation support on Air Traffic Controller behaviour with a Speed And Route Advisory function

    NARCIS (Netherlands)

    Merwe, K. van de; Oprins, E.A.P.B.; Plaat, A. van der; Erikson, F.

    2009-01-01

    The aim of this paper is to describe the influence of automation support on Air Traffic Controller performance, workload and Situation Awareness (SA). Controllers handle traffic through means of tactical control involving heading, speed and altitude instructions. Future Air Traffic Management (ATM)

  11. A Traffic Forecasting Method with Function to Control Residual Error Distribution for IP Access Networks

    Science.gov (United States)

    Kitahara, Takeshi; Furuya, Hiroki; Nakamura, Hajime

    Since traffic in IP access networks is less aggregated than in backbone networks, its variance could be significant and its distribution may be long-tailed rather than Gaussian in nature. Such characteristics make it difficult to forecast traffic volume in IP access networks for appropriate capacity planning. This paper proposes a traffic forecasting method that includes a function to control residual error distribution in IP access networks. The objective of the proposed method is to grasp the statistical characteristics of peak traffic variations, while conventional methods focus on average rather than peak values. In the proposed method, a neural network model is built recursively while weighting residual errors around the peaks. This enables network operators to control the trade-off between underestimation and overestimation errors according to their planning policy. Evaluation with a total of 136 daily traffic volume data sequences measured in actual IP access networks demonstrates the performance of the proposed method.

  12. 76 FR 54156 - National Standards for Traffic Control Devices; the Manual on Uniform Traffic Control Devices for...

    Science.gov (United States)

    2011-08-31

    ... contain collection information requirements for purposes of the PRA. Executive Order 12988 (Civil Justice..., Civil Justice Reform, to minimize litigation, eliminate ambiguity, and reduce burden. Executive Order... roads, Incorporation by reference, Signs, Traffic regulations. Issued on: August 23, 2011. Victor...

  13. The employment of a spoken language computer applied to an air traffic control task.

    Science.gov (United States)

    Laveson, J. I.; Silver, C. A.

    1972-01-01

    Assessment of the merits of a limited spoken language (56 words) computer in a simulated air traffic control (ATC) task. An airport zone approximately 60 miles in diameter with a traffic flow simulation ranging from single-engine to commercial jet aircraft provided the workload for the controllers. This research determined that, under the circumstances of the experiments carried out, the use of a spoken-language computer would not improve the controller performance.

  14. TRAFFIC CONTROLLED-DEDICATED SHORT RANGE COMMUNICATION: A SECURE COMMUNICATION USING TRAFFIC CONTROLLED DEDICATED SHORT RANGE COMMUNICATION MODEL IN VEHICULAR AD HOC NETWORKS FOR SAFETY RELATED SERVICES

    Directory of Open Access Journals (Sweden)

    K. Chandramohan

    2014-01-01

    Full Text Available To increase the road safety and secure communication among the vehicles in the network environment, Dedicated Short Range Communication (DSRC is followed. Nowadays, research over DSRC is dramatically increased for enhancing the road safety applications. The main task of DSRC is to protect the vehicles by communicating the warning message regarding the vehicle changing conditions, traffic occurrence and dangers over the road in the network. So, it is necessary to maintain the accurate communication timely with high reliability by implementing the appropriate protocol. In the literature there are several methods which provided specifications defined in the physical layer and the Medium Access Control (MAC layer. In those methods, current IEEE 802.11p MAC is not able to provide predictable Quality of Service (QoS for high-priority safety services. Motivated by the fact that the existing work provided three levels of safety-related broadcast services, but did not focus on current traffic load conditions, in this study, we plan to present Traffic Controlled DSRC (TC-DSRC model to analyze and categorize the traffic patterns in the vehicular communication for safety related application. A new algorithm is presented to evaluate the process of traffic controlled DSRC model for secure communication in VANET. The dedicated short range communication broadcast of messages is sent to all the vehicles at a specific instance for defined radius on the traffic zone. Multiple traffic load conditions are categorically stated to handle the vehicular safety with quick response time. Integrating these two performance metrics (i.e., quick response time and security, by using the proposed algorithm, the traffic patterns are categorized for communication between vehicles to provide the safety measure. In addition, our proposed scheme with the categorization using traffic patterns improves the network performance by deriving a specific pattern. Compared with the recent

  15. The Impact of Trajectory Prediction Uncertainty on Air Traffic Controller Performance and Acceptability

    Science.gov (United States)

    Mercer, Joey S.; Bienert, Nancy; Gomez, Ashley; Hunt, Sarah; Kraut, Joshua; Martin, Lynne; Morey, Susan; Green, Steven M.; Prevot, Thomas; Wu, Minghong G.

    2013-01-01

    A Human-In-The-Loop air traffic control simulation investigated the impact of uncertainties in trajectory predictions on NextGen Trajectory-Based Operations concepts, seeking to understand when the automation would become unacceptable to controllers or when performance targets could no longer be met. Retired air traffic controllers staffed two en route transition sectors, delivering arrival traffic to the northwest corner-post of Atlanta approach control under time-based metering operations. Using trajectory-based decision-support tools, the participants worked the traffic under varying levels of wind forecast error and aircraft performance model error, impacting the ground automations ability to make accurate predictions. Results suggest that the controllers were able to maintain high levels of performance, despite even the highest levels of trajectory prediction errors.

  16. Seasonal controlled traffic farming im ökologischen Gemüseanbau

    DEFF Research Database (Denmark)

    Hefner, Margita; Nørremark, Michael; Kristensen, Hanne Lakkenborg

    Problems of machinery induced soil compaction are evident in organic vegetable production, resulting in stunted root growth and reduced yield. Controlled traffic farming (CTF) provides a possibility to restrict soil compaction to wheel tracks and create traffic-free vegetable beds with improved...... soil structure. A field experiment was established at a commercial organic vegetable farm in Denmark to investigate the effect of CTF on the growth of cabbage (Brassica oleracea), potato (Solanum tuberosum) and beetroot (Beta vulgaris). Random traffic farming (RTF) served as the control. Preliminary...

  17. Optimal traffic light control method for a single intersection based on hybrid systems

    Institute of Scientific and Technical Information of China (English)

    赵晓华; 陈阳舟; 崔平远

    2003-01-01

    A single intersection of two phases is selected as a model to put forward a new optimal time-planning scheme for traffic light based on the model of hybrid automata for single intersection. A method of optimization is proposed for hybrid systems, and the average queue length over all queues is used as an objective function to find an optimal switching scheme for traffic light. It is illustrated that traffic light control for single intersection is a typical hybrid system, and the optimal planning-time scheme can be obtained using the optimal hybrid systems control based on the two stages method.

  18. Overcoming the Pigou-Downs Paradox Using Advanced Traffic Signal Control

    Science.gov (United States)

    Fowdur, S. C.; Rughooputh, S. D. D. V.

    2013-06-01

    Expansion of a road network has often been observed to cause more congestion and has led researchers to the formulation of traffic paradoxes such as the Pigou-Downs and the Braess paradoxes. In this paper, we present an application of advanced traffic signal control (ATSC) to overcome the Pigou-Downs paradox. Port Louis, the capital city of Mauritius is used to investigate the effect of using a harbor bridge to by-pass the city center. Using traffic cellular automata (TCA) simulations it has been shown how, if traffic is only gradually deviated along the by-pass, an overall longer travel time and decreased flux would result. By making use of ATSC, which involves traffic lights that sense the number of vehicles accumulated in the queue, better travel times and fluxes are achieved.

  19. Improving air traffic control: Proving new tools or approving the joint human-machine system?

    Science.gov (United States)

    Gaillard, Irene; Leroux, Marcel

    1994-01-01

    From the description of a field problem (i.e., designing decision aids for air traffic controllers), this paper points out how a cognitive engineering approach provides the milestones for the evaluation of future joint human-machine systems.

  20. Visual Problem Solving and Self‐regulation in Training Air Traffic Control

    NARCIS (Netherlands)

    Meeuwen van, Ludo

    2015-01-01

    Van Meeuwen, L. W. (2013). Visual problem solving and self-regulation in training air traffic control (Unpublished doctoral dissertation). Centre for Learning Sciences and Technologies, Open Universiteit, Heerlen, The Netherlands.

  1. Visual problem solving and self-regulation in training air traffic control

    NARCIS (Netherlands)

    Van Meeuwen, Ludo

    2013-01-01

    Van Meeuwen, L. W. (2013). Visual problem solving and self-regulation in training air traffic control (Unpublished doctoral dissertation). Centre for Learning Sciences and Technologies, Open Universiteit, Heerlen, The Netherlands.

  2. Personalised adaptive task selection in air traffic control: Effects on training efficiency and transfer.

    NARCIS (Netherlands)

    Salden, Ron; Paas, Fred; Van Merriënboer, Jeroen

    2008-01-01

    Salden, R.J.C.M., Paas, F., & Van Merriënboer, J.J.G. (2006). Personalised adaptive task selection in air traffic control: Effects on training efficiency and transfer. Learning and Instruction, 16, 350-362

  3. Multilevel Control & Optimization of Future Air Traffic Systems via Managem Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Controlling air traffic on all temporal and spatial scales – from a single aircraft to the entire airspace – can be formally stated as a dynamic,...

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

    Directory of Open Access Journals (Sweden)

    R. Yu. Lagerev

    2016-01-01

    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.

  5. APC-MAC/TA: Adaptive Power Controlled MAC Protocol with Traffic Awareness for Wireless Sensor Networks

    Science.gov (United States)

    Woo, Seok; Kim, Kiseon

    In this paper, we propose an adaptive power controlled MAC protocol with a traffic-aware scheme specifically designed to reduce both energy and latency in wireless sensor networks. Typically, existing MAC protocols for sensor networks sacrifice latency performance for node energy efficiency. However, some sensor applications for emergencies require rather fast transmissions of sensed data, where we need to consider both energy and latency together. The proposed MAC protocol includes two novel ideas: one is a transmission power control scheme for improving latency in high traffic loads, and the other is a traffic-aware scheme to save more energy in low traffic loads. The transmission power control scheme increases channel utilization by mitigating interference between nodes, and the traffic-aware scheme allows nodes to sleep to reduce idle energy consumption when there are no traffic loads in a network. Simulation results show that the proposed protocol significantly reduces the latency as well as the energy consumption compared to the S-MAC protocol specifically for a large transmission power of nodes and low network traffic.

  6. Real-time routing control design for traffic networks with multi-route choices

    Institute of Scientific and Technical Information of China (English)

    罗莉华; 葛颖恩; 陈继红; 张方伟

    2016-01-01

    This work considers those road networks in which there are multi-route choices for bifurcation-destination (or origin-destination) pairs, and designs a real-time variable message sign (VMS)-based routing control strategy in the model predictive control (MPC) framework. The VMS route recommendation provided by the traffic management authority is directly considered as the control variable, and the routing control model is established, in which a multi-dimensional control vector is introduced to describe the influence of route recommendations on flow distribution. In the MPC framework, a system optimum routing strategy with the constraints regarding drivers’ acceptability with recommended routes is designed, which can not only meet the traffic management authority’s control requirement but also improve drivers’ satisfaction with the route guidance system. The simulation carried out shows that the proposed routing control can effectively mitigate traffic congestion, reduces followers’ time delay, and improves drivers’ satisfaction with routing control in road networks.

  7. Controlling traffic jams on a two-lane road using delayed-feedback signals

    Institute of Scientific and Technical Information of China (English)

    Liang ZHENG; Shi-quan ZHONG; Shou-feng MA

    2012-01-01

    This paper focuses mainly on the stability analysis of two-lane traffic flow with lateral friction,which may be caused by irregular driving behavior or poorly visible road markings,and also attempts to reveal the formation mechanism of traffic jams.Firstly,a two-lane optimal velocity (OV) model without control signals is proposed and its stability condition is obtained from the viewpoint of control theory.Then delayed-feedback control signals composed of distance headway information from both lanes are added to each vehicle and a vehicular control system is designed to suppress the traffic jams.Lane change behaviors are also incorporated into the two-lane OV model and the corresponding information about distance headway and feedback signals is revised.Finally,the results of numerical experiments are shown to verify that when the stability condition is not met,the position disturbances and resulting lane change behaviors do indeed deteriorate traffic performance and cause serious traffic jams.However,once the proper delayed-feedback control signals are implemented,the traffic jams can be suppressed efficiently.

  8. THE REMOTE AND MOBILE AIR TRAFFIC CONTROL TOWER AND ITS POSSIBLE APPLICATION TO THE OPERATIONAL AREA

    Directory of Open Access Journals (Sweden)

    Tímea VAS

    2014-10-01

    Full Text Available The concept of remote and mobile Air Traffic Control Tower (ATC TWR and its development has started in Europe, Australia and also in the USA, in order to improve the efficiency of Air Traffic Management (ATM systems in terms of air transportation safety. These new technologies are applicable in many countries in peace time, but on mobility reasons these are promoted to achieve commitments in the operational area. This article describes the devices and range of equipment of mobile and remote tower, and their specifications, which can even serve a medium sized airport, furthermore examines, whether how can those provide the air traffic services at an operational airfield.

  9. Predictive control strategies for energy saving of hybrid electric vehicles based on traffic light information

    Directory of Open Access Journals (Sweden)

    Kaijiang YU

    2015-10-01

    Full Text Available As the conventional control method for hybrid electric vehicle doesn’t consider the effect of known traffic light information on the vehicle energy management, this paper proposes a model predictive control intelligent optimization strategies based on traffic light information for hybrid electric vehicles. By building the simplified model of the hybrid electric vehicle and adopting the continuation/generalized minimum residual method, the model prediction problem is solved. The simulation is conducted by using MATLAB/Simulink platform. The simulation results show the effectiveness of the proposed model of the traffic light information, and that the proposed model predictive control method can improve fuel economy and the real-time control performance significantly. The research conclusions show that the proposed control strategy can achieve optimal control of the vehicle trajectory, significantly improving fuel economy of the vehicle, and meet the system requirements for the real-time optimal control.

  10. Air Traffic Controllers' Control Strategies in the Terminal Area Under Off-Nominal Conditions

    Science.gov (United States)

    Martin, Lynne; Mercer, Joey; Callantine, Todd; Kupfer, Michael; Cabrall, Christopher

    2012-01-01

    A human-in-the-loop simulation investigated the robustness of a schedule-based terminal-area air traffic management concept, and its supporting controller tools, to off-nominal events - events that led to situations in which runway arrival schedules required adjustments and controllers could no longer use speed control alone to impose the necessary delays. The main research question was exploratory: to assess whether controllers could safely resolve and control the traffic during off-nominal events. A focus was the role of the supervisor - how he managed the schedules, how he assisted the controllers, what strategies he used, and which combinations of tools he used. Observations and questionnaire responses revealed supervisor strategies for resolving events followed a similar pattern: a standard approach specific to each type of event often resolved to a smooth conclusion. However, due to the range of factors influencing the event (e.g., environmental conditions, aircraft density on the schedule, etc.), sometimes the plan required revision and actions had a wide-ranging effect.

  11. Development of control strategy of variable speed limits for improving traffic operations at freeway bottlenecks

    Institute of Scientific and Technical Information of China (English)

    李志斌; 刘攀; 王炜; 徐铖铖

    2014-01-01

    A control strategy of variable speed limits (VSL) was developed to reduce the travel time at freeway recurrent bottleneck areas. The proposed control strategy particularly focused on preventing the capacity drop and increasing the discharge flow. A cell transmission model (CTM) was developed to evaluate the effects of the proposed VSL control strategy on the traffic operations. The results show that the total travel time is reduced by 25.5% and the delay is reduced by 56.1%. The average travel speed is increased by 34.3% and the queue length is reduced by 31.0%. The traffic operation is improved by the proposed VSL control strategy. The way to use the proposed VSL control strategy in different types of freeway bottlenecks was also discussed by considering different traffic flow characteristics. It is concluded that the VSL control strategy is effective for merge bottlenecks but is less effective for diverge bottlenecks.

  12. New control strategy for the lattice hydrodynamic model of traffic flow

    Science.gov (United States)

    Zhu, Chenqiang; Zhong, Shiquan; Li, Guangyu; Ma, Shoufeng

    2017-02-01

    The new delayed-feedback control strategy is applied for lattice hydrodynamic model of traffic flow by considering the control signal of the variation rate of the optimal velocity. The linear stability condition is derived in the frequency-domain with control theory. Then, different feedback gains under the periodic boundary scenery and on-ramp scenery are simulated. The periodic boundary scenery provides an initial small disturbance situation on the circle road, while the on-ramp scenery reproduces the disturbance triggered by the on-ramp on the open road. Both the theoretical analysis and simulations show that this new control signal has a positive effect to suppress traffic jams.

  13. Traffic flow collection wireless sensor network node for intersection light control

    Science.gov (United States)

    Li, Xu; Li, Xue

    2011-10-01

    Wireless sensor network (WSN) is expected to be deployed in intersection to monitor the traffic flow continuously, and the monitoring datum can be used as the foundation of traffic light control. In this paper, a WSN based on ZigBee protocol for monitoring traffic flow is proposed. Structure, hardware and work flow of WSN nodes are designed. CC2431 from Texas Instrument is chosen as the main computational and transmission unit, and CC2591 as the amplification unit. The stability experiment and the actual environment experiment are carried out in the last of the paper. The results of experiments show that WSN has the ability to collect traffic flow information quickly and transmit the datum to the processing center in real time.

  14. Breakdown minimization principle versus Wardrop's equilibria for dynamic traffic assignment and control in traffic and transportation networks: A critical mini-review

    Science.gov (United States)

    Kerner, Boris S.

    2017-01-01

    We review physical results of applications of the breakdown minimization (BM) principle versus applications of the classical Wardrop's equilibria (Wardrop's user equilibrium (UE) and system optimum (SO)) for dynamic traffic assignment and control in traffic and transportation networks. It is shown that depending on the total network inflow rate there are two different applications of the BM principle: (i) The network throughput maximization approach that maximizes the network throughput ensuring free flow conditions in the network. (ii) The minimization of the network breakdown probability at relatively large network inflow rates. Probabilistic features of the application of the BM principle are studied. We have found that when the application of the BM principle cannot prevent traffic breakdown in the network, nevertheless, a combination of the application of the BM principle with dynamic control of traffic breakdown at network bottlenecks can lead to the dissolution of traffic congestion. We show that applications of the classical Wardrop's equilibria for dynamic traffic assignment deteriorate basically the traffic system in networks.

  15. Improving Performance in Dense Wireless Spaces by Controlling Bulk Traffic

    Directory of Open Access Journals (Sweden)

    Marat Zhanikeev

    2017-01-01

    Full Text Available The growing number of wireless devices nowadays often results in congestion of wireless channels. In research, this topic is referred to as networking in dense wireless spaces. The literature on the topic shows that the biggest problem is the high number of concurrent sessions to a wireless access point. The obvious solution is to reduce the number of concurrent sessions. This paper proposes a simple method called Bulk-n-Pick which minimizes the number of prolonged concurrent sessions by separating bulk from sync traffic. Aiming at educational applications, under the proposed design, web applications would distribute the main bulk of content once at the beginning of a class and then rely on small messages for real time sync traffic during the class. For realistic performance analysis, this paper first performs real-life experiments with various counts of wireless devices, bulk sizes, and levels of sync intensity. Based on the experiments, this paper shows that the proposed Bulk-n-Pick method outperforms the traditional design even when only two concurrent bulk sessions are allowed. The experiment shows that up to 10 concurrent bulk sessions are feasible in practice. Based on these results, a method for online performance optimization is proposed and validated in a trace-based emulation.

  16. The Study of Reinforcement Learning for Traffic Self-Adaptive Control under Multiagent Markov Game Environment

    Directory of Open Access Journals (Sweden)

    Lun-Hui Xu

    2013-01-01

    Full Text Available Urban traffic self-adaptive control problem is dynamic and uncertain, so the states of traffic environment are hard to be observed. Efficient agent which controls a single intersection can be discovered automatically via multiagent reinforcement learning. However, in the majority of the previous works on this approach, each agent needed perfect observed information when interacting with the environment and learned individually with less efficient coordination. This study casts traffic self-adaptive control as a multiagent Markov game problem. The design employs traffic signal control agent (TSCA for each signalized intersection that coordinates with neighboring TSCAs. A mathematical model for TSCAs’ interaction is built based on nonzero-sum markov game which has been applied to let TSCAs learn how to cooperate. A multiagent Markov game reinforcement learning approach is constructed on the basis of single-agent Q-learning. This method lets each TSCA learn to update its Q-values under the joint actions and imperfect information. The convergence of the proposed algorithm is analyzed theoretically. The simulation results show that the proposed method is convergent and effective in realistic traffic self-adaptive control setting.

  17. In-Trail Procedure Air Traffic Control Procedures Validation Simulation Study

    Science.gov (United States)

    Chartrand, Ryan C.; Hewitt, Katrin P.; Sweeney, Peter B.; Graff, Thomas J.; Jones, Kenneth M.

    2012-01-01

    In August 2007, Airservices Australia (Airservices) and the United States National Aeronautics and Space Administration (NASA) conducted a validation experiment of the air traffic control (ATC) procedures associated with the Automatic Dependant Surveillance-Broadcast (ADS-B) In-Trail Procedure (ITP). ITP is an Airborne Traffic Situation Awareness (ATSA) application designed for near-term use in procedural airspace in which ADS-B data are used to facilitate climb and descent maneuvers. NASA and Airservices conducted the experiment in Airservices simulator in Melbourne, Australia. Twelve current operational air traffic controllers participated in the experiment, which identified aspects of the ITP that could be improved (mainly in the communication and controller approval process). Results showed that controllers viewed the ITP as valid and acceptable. This paper describes the experiment design and results.

  18. Particle number emissions of motor traffic derived from street canyon measurements in a Central European city

    Science.gov (United States)

    Klose, S.; Birmili, W.; Voigtländer, J.; Tuch, T.; Wehner, B.; Wiedensohler, A.; Ketzel, M.

    2009-02-01

    A biennial dataset of ambient particle number size distributions (diameter range 4-800 nm) collected in urban air in Leipzig, Germany, was analysed with respect to the influence of traffic emissions. Size distributions were sampled continuously in 2005 and 2006 inside a street canyon trafficked by ca. 10 000 motor vehicles per day, and at a background reference site distant at 1.5 km. Auto-correlation analysis showed that the impact of fresh traffic emissions could be seen most intensely below particle sizes of 60 nm. The traffic-induced concentration increment at roadside was estimated by subtracting the urban background values from the street canyon measurement. To describe the variable dispersion conditions inside the street canyon, micro-meteorological dilution factors were calculated using the Operational Street Pollution Model (OSPM), driven by above-roof wind speed and wind direction observations. The roadside increment concentrations, dilution factor, and real-time traffic counts were used to calculate vehicle emission factors (aerosol source rates) that are representative of the prevailing driving conditions, i.e. stop-and-go traffic including episodes of fluent traffic flow at speeds up to 40 km h-1. The size spectrum of traffic-derived particles was essentially bimodal - with mode diameters around 12 and 100 nm, while statistical analysis suggested that the emitted number concentration varied with time of day, wind direction, particle size and fleet properties. Significantly, the particle number emissions depended on ambient temperature, ranging between 4.8 (±1.8) and 7.8 (±2.9).1014 p. veh-1 km-1 in summer and winter, respectively. A separation of vehicle types according to vehicle length suggested that lorry-like vehicles emit about 80 times more particle number than passenger car-like vehicles. Using nitrogen oxide (NOx) measurements, specific total particle number emissions of 338 p. (pg NOx)-1 were inferred. The calculated traffic emission factors

  19. Air Traffic Controller Acceptability of Unmanned Aircraft System Detect-and-Avoid Thresholds

    Science.gov (United States)

    Mueller, Eric R.; Isaacson, Douglas R.; Stevens, Derek

    2016-01-01

    A human-in-the-loop experiment was conducted with 15 retired air traffic controllers to investigate two research questions: (a) what procedures are appropriate for the use of unmanned aircraft system (UAS) detect-and-avoid systems, and (b) how long in advance of a predicted close encounter should pilots request or execute a separation maneuver. The controller participants managed a busy Oakland air route traffic control sector with mixed commercial/general aviation and manned/UAS traffic, providing separation services, miles-in-trail restrictions and issuing traffic advisories. Controllers filled out post-scenario and post-simulation questionnaires, and metrics were collected on the acceptability of procedural options and temporal thresholds. The states of aircraft were also recorded when controllers issued traffic advisories. Subjective feedback indicated a strong preference for pilots to request maneuvers to remain well clear from intruder aircraft rather than deviate from their IFR clearance. Controllers also reported that maneuvering at 120 seconds until closest point of approach (CPA) was too early; maneuvers executed with less than 90 seconds until CPA were more acceptable. The magnitudes of the requested maneuvers were frequently judged to be too large, indicating a possible discrepancy between the quantitative UAS well clear standard and the one employed subjectively by manned pilots. The ranges between pairs of aircraft and the times to CPA at which traffic advisories were issued were used to construct empirical probability distributions of those metrics. Given these distributions, we propose that UAS pilots wait until an intruder aircraft is approximately 80 seconds to CPA or 6 nmi away before requesting a maneuver, and maneuver immediately if the intruder is within 60 seconds and 4 nmi. These thresholds should make the use of UAS detect and avoid systems compatible with current airspace procedures and controller expectations.

  20. Autonomous Traffic Control System Using Agent Based Technology

    CERN Document Server

    M, Venkatesh; V, Srinivas

    2011-01-01

    The way of analyzing, designing and building of real-time projects has been changed due to the rapid growth of internet, mobile technologies and intelligent applications. Most of these applications are intelligent, tiny and distributed components called as agent. Agent works like it takes the input from numerous real-time sources and gives back the real-time response. In this paper how these agents can be implemented in vehicle traffic management especially in large cities and identifying various challenges when there is a rapid growth of population and vehicles. In this paper our proposal gives a solution for using autonomous or agent based technology. These autonomous or intelligent agents have the capability to observe, act and learn from their past experience. This system uses the knowledge flow of precedent signal or data to identify the incoming flow of forthcoming signal. Our architecture involves the video analysis and exploration using some Intelligence learning algorithm to estimate and identify the...

  1. Optimal Control Strategy for Traffic Driven Epidemic Spreading Based on Community Structure

    Directory of Open Access Journals (Sweden)

    Fei Shao

    2013-01-01

    Full Text Available It is shown that community structure has a great impact on traffic transportation and epidemic spreading. The density of infected nodes and the epidemic threshold have been proven to have significant relationship with the node betweenness in traffic driven epidemic spreading method. In this paper, considering the impact of community structure on traffic driven epidemic spreading, an effective and novel strategy to control epidemic spreading in scale-free networks is proposed. Theoretical analysis shows that the new control strategy will obviously increase the ratio between the first and the second moments of the node betweenness distribution in scale-free networks. It is also found that the more accurate the community is identified, the stronger community structure the network has and the more efficient the control strategy is. Simulations on both computer-generated and real-world networks have confirmed the theoretical results.

  2. Estimation and Control of Networked Distributed Parameter Systems: Application to Traffic Flow

    KAUST Repository

    Canepa, Edward

    2016-11-01

    The management of large-scale transportation infrastructure is becoming a very complex task for the urban areas of this century which are covering bigger geographic spaces and facing the inclusion of connected and self-controlled vehicles. This new system paradigm can leverage many forms of sensing and interaction, including a high-scale mobile sensing approach. To obtain a high penetration sensing system on urban areas more practical and scalable platforms are needed, combined with estimation algorithms suitable to the computational capabilities of these platforms. The purpose of this work was to develop a transportation framework that is able to handle different kinds of sensing data (e.g., connected vehicles, loop detectors) and optimize the traffic state on a defined traffic network. The framework estimates the traffic on road networks modeled by a family of Lighthill-Whitham-Richards equations. Based on an equivalent formulation of the problem using a Hamilton-Jacobi equation and using a semi-analytic formula, I will show that the model constraints resulting from the Hamilton-Jacobi equation are linear, albeit with unknown integer variables. This general framework solve exactly a variety of problems arising in transportation networks: traffic estimation, traffic control (including robust control), cybersecurity and sensor fault detection, or privacy analysis of users in probe-based traffic monitoring systems. This framework is very flexible, fast, and yields exact results. The recent advances in sensors (GPS, inertial measurement units) and microprocessors enable the development low-cost dedicated devices for traffic sensing in cities, 5 which are highly scalable, providing a feasible solution to cover large urban areas. However, one of the main problems to address is the privacy of the users of the transportation system, the framework presented here is a viable option to guarantee the privacy of the users by design.

  3. Fuzzy Neural Network Based Traffic Prediction and Congestion Control in High-Speed Networks

    Institute of Scientific and Technical Information of China (English)

    费翔; 何小燕; 罗军舟; 吴介一; 顾冠群

    2000-01-01

    Congestion control is one of the key problems in high-speed networks, such as ATM. In this paper, a kind of traffic prediction and preventive congestion control scheme is proposed using neural network approach. Traditional predictor using BP neural network has suffered from long convergence time and dissatisfying error. Fuzzy neural network developed in this paper can solve these problems satisfactorily. Simulations show the comparison among no-feedback control scheme,reactive control scheme and neural network based control scheme.

  4. P2P network traffic control mechanism based on global evaluation values

    Institute of Scientific and Technical Information of China (English)

    XU Xiao-long; WANG Ru-chuan

    2009-01-01

    Peer-to-peer (P2P) computing technology has been widely used on the Internet to exchange data. However, it occupies much network bandwidth, and thus greatly influences traditional business on the Interact. Besides, problems about free-riders and 'tragedy of the commons' in the P2P environment estrange from it P2P users who constantly contribute to the network with quality resources. This article proposes a new P2P network traffic control mechanism based on global evaluation values. It aims to help individual users to avoid peak traffic time as much as possible, ease network congestion and protect traditional business on the Interact, as well as differentiating priority grades of peers according to their contributions and stimulating them to share their valuable resources actively. This article first analyzes the current state of network traffic, and then elaborates on P2P network traffic control policies and proposes the peer's priority level differentiation mechanism based on global evaluation values. Finally,after the testing results and analysis of the proposed P2P network traffic control mechanism are discussed, conclusions are drawn.

  5. Controlled Traffic Farming – From Worldwide Research To Adoption In Europe And Its Future Prospects

    Directory of Open Access Journals (Sweden)

    Chamen Tim

    2015-09-01

    Full Text Available Controlled traffic farming is a machinery management system that confines all field vehicles to the least possible area of permanent traffic lanes. It has developed in response to research evidence of widespread soil damage from compaction due to field traffic. The history of research on soil compaction is explored and found to be a relatively new phenomenon. Controlled traffic farming as a topic for research did not appear until the 1980s although its principles and benefits were well established before then. Research expanded over the next decades but changed subtly to more reviews on the topic as well as emphasis on environmental deliverables and some economics studies. Few if any researchers attempted to develop on-farm systems using existing machinery until the mid 1990s when a small and dedicated team in Australia encouraged farmers to experiment. This quickly led to rapid expansion across the continent to its present day c. 13% of the cropped area. Despite changes to extension services in northern Europe at around the turn of the century and a move to subsidiarity, this did not alter the model of controlled traffic adoption. This followed a similar pattern to that in Australia involving individuals rather than organizations.

  6. Controlling Air Traffic (Simulated) in the Presence of Automation (CATS PAu) 1995: A Study of Measurement Techniques for Situation Awareness in Air Traffic Control

    Science.gov (United States)

    French, Jennifer R.

    1995-01-01

    As automated systems proliferate in aviation systems, human operators are taking on less and less of an active role in the jobs they once performed, often reducing what should be important jobs to tasks barely more complex than monitoring machines. When operators are forced into these roles, they risk slipping into hazardous states of awareness, which can lead to reduced skills, lack of vigilance, and the inability to react quickly and competently when there is a machine failure. Using Air Traffic Control (ATC) as a model, the present study developed tools for conducting tests focusing on levels of automation as they relate to situation awareness. Subjects participated in a two-and-a-half hour experiment that consisted of a training period followed by a simulation of air traffic control similar to the system presently used by the FAA, then an additional simulation employing automated assistance. Through an iterative design process utilizing numerous revisions and three experimental sessions, several measures for situational awareness in a simulated Air Traffic Control System were developed and are prepared for use in future experiments.

  7. Risk Assessment on the Transition Program for Air Traffic Control Automation System Upgrade

    Directory of Open Access Journals (Sweden)

    Li Dong Bin

    2016-01-01

    Full Text Available We analyzed the safety risks of the transition program for Air Traffic Control (ATC automation system upgrade by using the event tree analysis method in this paper. We decomposed the occurrence progress of the three transition phase and built the event trees corresponding to the three stages, and then we determined the probability of success of each factor and calculated probability of success of the air traffic control automation system upgrade transition. In the conclusion, we illustrate the transition program safety risk according to the results.

  8. 49 CFR 236.401 - Automatic block signal system and interlocking standards applicable to traffic control systems.

    Science.gov (United States)

    2010-10-01

    ... TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Traffic Control Systems Standards § 236.401 Automatic... 49 Transportation 4 2010-10-01 2010-10-01 false Automatic block signal system and interlocking standards applicable to traffic control systems. 236.401 Section 236.401 Transportation Other...

  9. ROLE OF PEDAGOGY COMPETENCE OF A CONTROLLER-TRAINER IN SIMU-TRAINING OF AIR TRAFFIC CONTROLLERS

    Directory of Open Access Journals (Sweden)

    О. Петращук

    2012-04-01

    Full Text Available The article focuses on the issue of pedagogy competence of an ATCO-trainer as a constituent of hisoverall professional competency/capacity to provide quality SIMU- training of the air traffic controllers. Thecurrent University curriculum for abinitio controllers does not provide developing of the pedagogicalcompetence. But it is requested very much when an air traffic controller is employed as a controller-trainerfor SIMU-training. It is suggested to include pedagogical science as a course in the University programme

  10. AN INTELLIGENT TRAFFIC LIGHTS CONTROL ALGORITHM BASED ON TRAFFIC FLOW%基于车流量的交通灯智能控制算法

    Institute of Scientific and Technical Information of China (English)

    王鼎湘; 李茂军

    2015-01-01

    随着道路交通流量日益增加,现有交通灯使用的时间固定控制方法并不能很好地满足各种复杂交通情况。针对这一背景,在使用视频图像对车辆跟踪计数实时采集车流量的基础上,提出一种根据各方向车流量控制交通灯时间的算法。该算法根据实时的车流情况更新各方向的绿灯分配时间,自动调节各方向绿灯时间比例,并根据路口总车流量的大小智能调节绿灯时间周期大小。基于 Delphi 平台对算法进行仿真,结果表明:该算法能根据实时车流信息自适应调整各方向绿灯时长,并通过自动调节各方向绿灯时间总和来有效实现交通拥堵或畅通情况下交通灯的智能控制。%The time-fixed control method used by existing traffic lights can not well satisfy various complicated traffic conditions along with the increasingly growth of road traffic flow.Under this background and based on the acquisition of real-time traffic flow by using video images to track and count vehicles,we propose an algorithm of controlling traffic lights time according to the traffic flow from various directions.This algorithm updates the allocated time for green lights in each direction based upon real-time traffic situation and automatically adjusts the time scale of green lights in various directions.It also intelligently regulates the size of the time cycle of green lights according to the total traffic flow on intersections.The algorithm is simulated based on Delphi platform,the results show that the proposed algorithm can adaptively adjust the time length of green lights in each direction based on real-time vehicles traffic information,and effectively realises the intelligent traffic lights control in the circumstances of traffic congestion or in smooth flow by automatically adjusting the total time of green lights in different di-rections.

  11. GENERAL: A control method for congested traffic in the coupled map car-following model

    Science.gov (United States)

    Shen, Fei-Ying; Ge, Hong-Xia; Zhang, Hui; Yu, Han-Mei; Lei, Li

    2009-10-01

    Based on the pioneer work of Konishi et al, a new control method is presented to suppress the traffic congestion in the coupled map (CM) car-following model under an open boundary. A control signal concluding the velocity differences of the two vehicles in front is put forward. The condition under which the traffic jam can be contained is analyzed. The results are compared with that presented by Konishi et al [Phys. Rev. 1999 E 60 4000-4007]. The simulation results show that the temporal behavior obtained by our method is better than that by the Konishi's et al. method, although both the methods could suppress the traffic jam. The simulation results are consistent with the theoretical analysis.

  12. A control method for congested traffic in the coupled map car-following model

    Institute of Scientific and Technical Information of China (English)

    Shen Fei-Ying; Ge Hong-Xia; Zhang Hui; Yu Han-Mei; Lei Li

    2009-01-01

    Based on the pioneer work of Konishi et al, a new control method is presented to suppress the traffic congestion in the coupled map (CM) car-following model under an open boundary. A control signal concluding the velocity differences of the two vehicles in front is put forward. The condition under which the traffic jam can be contained is analyzed. The results are compared with that presented by Konishi et al [Phys. Rev. 1999 E 60 4000-4007]. The simulation results show that the temporal behavior obtained by our method is better than that by the Konishi's et al. method, although both the methods could suppress the traffic jam. The simulation results are consistent with the theoretical analysis.

  13. Socioeconomic impact of widespread adoption of precision farming and controlled traffic systems in Denmark

    DEFF Research Database (Denmark)

    Jensen, Hans Grinsted; Jacobsen, Lars Bo; Pedersen, Søren Marcus;

    2012-01-01

    In this study we assess the economic profitability of implementing various precision farming (PF) technologies and controlled traffic farming (CTF) on 4 main crops in Denmark. The study provides insight into technological requirements, and identifies related costs and benefits to farmers and the ...... to politicians since it clearly facilitates aims of environmental policies currently under implementation by the Danish government.......In this study we assess the economic profitability of implementing various precision farming (PF) technologies and controlled traffic farming (CTF) on 4 main crops in Denmark. The study provides insight into technological requirements, and identifies related costs and benefits to farmers....... The obtained results reflect the long term economic effect of implementing new production methods in Denmark where soil fertility increases over time due to reduced traffic increasing yields. Over all, the Danish GDP is estimated to increase by 34 million € due to the implementation of PF and CTF on larger...

  14. Traffic flow model at fixed control signals with discrete service time distribution

    Directory of Open Access Journals (Sweden)

    Lucky I. Igbinosun

    2016-04-01

    Full Text Available Most of the models of road traffic flow at fixed-cycle controlled intersection assume stationary distributions and provide steady state results. The assumption that a constant number of vehicles can leave the system during the green phase is unrealistic in real life situations. A discrete time queuing model was developed to describe the operation of traffic flow at a road intersection with fixed-cycle signalized control and to account for the randomness in the number of vehicles that can leave the system. The results show the expected queue size in the system when the traffic is light and for a busy period, respectively. For the light period, when the traffic intensity is less than one, it takes a shorter green cycle time for vehicles to clear up than during high traffic intensity (the road junction is saturated. Increasing the number of cars that can leave the junction at the turn of the green phase reduces the number of cycle times before the queue is cleared.

  15. Characterization of Visual Scanning Patterns in Air Traffic Control

    Directory of Open Access Journals (Sweden)

    Sarah N. McClung

    2016-01-01

    Full Text Available Characterization of air traffic controllers’ (ATCs’ visual scanning strategies is a challenging issue due to the dynamic movement of multiple aircraft and increasing complexity of scanpaths (order of eye fixations and saccades over time. Additionally, terminologies and methods are lacking to accurately characterize the eye tracking data into simplified visual scanning strategies linguistically expressed by ATCs. As an intermediate step to automate the characterization classification process, we (1 defined and developed new concepts to systematically filter complex visual scanpaths into simpler and more manageable forms and (2 developed procedures to map visual scanpaths with linguistic inputs to reduce the human judgement bias during interrater agreement. The developed concepts and procedures were applied to investigating the visual scanpaths of expert ATCs using scenarios with different aircraft congestion levels. Furthermore, oculomotor trends were analyzed to identify the influence of aircraft congestion on scan time and number of comparisons among aircraft. The findings show that (1 the scanpaths filtered at the highest intensity led to more consistent mapping with the ATCs’ linguistic inputs, (2 the pattern classification occurrences differed between scenarios, and (3 increasing aircraft congestion caused increased scan times and aircraft pairwise comparisons. The results provide a foundation for better characterizing complex scanpaths in a dynamic task and automating the analysis process.

  16. Towards reducing traffic congestion using cooperative adaptive cruise control on a freeway with a ramp

    Directory of Open Access Journals (Sweden)

    Georges Arnaout

    2011-12-01

    Full Text Available Purpose: In this paper, the impact of Cooperative Adaptive Cruise Control (CACC systems on traffic performance is examined using microscopic agent-based simulation. Using a developed traffic simulation model of a freeway with an on-ramp - created to induce perturbations and to trigger stop-and-go traffic, the CACC system’s effect on the traffic performance is studied. The previously proposed traffic simulation model is extended and validated. By embedding CACC vehicles in different penetration levels, the results show significance and indicate the potential of CACC systems to improve traffic characteristics and therefore can be used to reduce traffic congestion. The study shows that the impact of CACC is positive but is highly dependent on the CACC market penetration. The flow rate of the traffic using CACC is proportional to the market penetration rate of CACC equipped vehicles and the density of the traffic.Design/methodology/approach: This paper uses microscopic simulation experiments followed by a quantitative statistical analysis. Simulation enables researchers manipulating the system variables to straightforwardly predict the outcome on the overall system, giving researchers the unique opportunity to interfere and make improvements to performance. Thus with simulation, changes to variables that might require excessive time, or be unfeasible to carry on real systems, are often completed within seconds.Findings: The findings of this paper are summarized as follow:•\tProvide and validate a platform (agent-based microscopic traffic simulator in which any CACC algorithm (current or future may be evaluated.•\tProvide detailed analysis associated with implementation of CACC vehicles on freeways.•\tInvestigate whether embedding CACC vehicles on freeways has a significant positive impact or not.Research limitations/implications: The main limitation of this research is that it has been conducted solely in a computer laboratory. Laboratory

  17. 基于车流量的交通灯控制系统设计%Traffic Light Control System Design Based on Traffic Flow

    Institute of Scientific and Technical Information of China (English)

    章伟; 张代远

    2015-01-01

    As traffic congestion rises within urban around the world,the intelligent control of traffic signals within cities is becoming in-creasingly important. Previous research for the area of intelligent traffic signal control has several shortcomings,including a reliance on historical data,fixing timing,not solving complicated and changeable situation. Propose the intelligent traffic lights control system based on traffic flow in this paper. It can get real-time traffic information with the help of video detection technology,and design the time algo-rithm that based on the information measured to adjust the control of the time of green light in all lanes,which can accurately change the time of traffic lights by achieving traffic dynamic adjustment. This solution allows signals to be updated frequently to match current traffic demand. It can alleviate traffic pressure,improve efficiency,save people's time and energy and protect the environment.%随着在世界各地交通拥堵现象日趋严重,城市内的交通信号智能控制变得越来越重要。先前研究的智能交通信号控制领域内有几个缺点,包括:依赖历史数据、固定配时、不能解决现实复杂多变的环境。文中提出的基于车流量的智能交通灯控制系统,利用视频检测技术,测得路口的实时车流信息,并依据所测得的信息设计了时间分配控制算法来调整控制各车道的绿灯时间,实时改变交通灯的时长以实现车流动态调节,该方案允许信号实时被更新以匹配当前的交通需求。运用到实际可达到缓解交通压力、提高通行效率、节省出行时间、节能减排、保护环境的目的。

  18. Traffic Control Under Complex Weather Conditions in Suining Airport

    Institute of Scientific and Technical Information of China (English)

    吕维峰

    2014-01-01

    Complex weather conditions is meaning thunderstorm freezing turbulence wind-shear low visibility weather affect the flight safety. When confronted with complex weather conditions,the controllers should know the weather condition and trend weather,and notify the aircraft under your control zone.The controllers provide the required services to the pilots,help the pilots to avoid the complex weather.In this paper, through different complex weathers under different control command,get the different methods of control.

  19. Introduction to FAST central control system

    Science.gov (United States)

    Sun, Jinghai; Zhu, Lichun; Jiang, Zhiqian

    2016-07-01

    FAST is the largest single dish radio telescope in the world. During observation, part of spherical reflector forms paraboloid to the source direction, meanwhile the feed is placed to instant focus. The control of telescope is difficult and complicated. An autonomous central control system is designed and implemented for methodically and efficiently operation. The system connects and coordinates all subsystems including control, measurement and health monitoring for reflector, feed support and receiver respectively. The main functions are managing observation tasks, commanding subsystems, storing operating data, monitoring statuses and providing the uniform time standard. In this paper, the functions, software and hardware of FAST central control system are presented. The relative infrastructures such as power, network and control room arrangement are introduced.

  20. How Life Experience Shapes Cognitive Control Strategies: The Case of Air Traffic Control Training.

    Directory of Open Access Journals (Sweden)

    Sandra Arbula

    Full Text Available Although human flexible behavior relies on cognitive control, it would be implausible to assume that there is only one, general mode of cognitive control strategy adopted by all individuals. For instance, different reliance on proactive versus reactive control strategies could explain inter-individual variability. In particular, specific life experiences, like a highly demanding training for future Air Traffic Controllers (ATCs, could modulate cognitive control functions. A group of ATC trainees and a matched group of university students were tested longitudinally on task-switching and Stroop paradigms that allowed us to measure indices of cognitive control. The results showed that the ATCs, with respect to the control group, had substantially smaller mixing costs during long cue-target intervals (CTI and a reduced Stroop interference effect. However, this advantage was present also prior to the training phase. Being more capable in managing multiple task sets and less distracted by interfering events suggests a more efficient selection and maintenance of task relevant information as an inherent characteristic of the ATC group, associated with proactive control. Critically, the training that the ATCs underwent improved their accuracy in general and reduced response time switching costs during short CTIs only. These results indicate a training-induced change in reactive control, which is described as a transient process in charge of stimulus-driven task detection and resolution. This experience-based enhancement of reactive control strategy denotes how cognitive control and executive functions in general can be shaped by real-life training and underlines the importance of experience in explaining inter-individual variability in cognitive functioning.

  1. The Application of The Double Queue Asymmetric Gated Service Polling Control Theory in Intelligent Traffic System

    Directory of Open Access Journals (Sweden)

    Zhao Yi Fan

    2016-01-01

    Full Text Available paper presents a new use of double queues asymmetric gated service polling system in the intelligent traffic light control system.Usually there are more vehicles in main road than minor road,so there are more green light time be needed in the main road.From the computer simulation and theory analysis,we can find that the application of double queues asymmetric gated service polling theory in intelligent traffic system can balance intersections load and set suitable passing time for vehicles to assure the roads open.

  2. Jam-avoiding adaptive cruise control (ACC) and its impact on traffic dynamics

    CERN Document Server

    Kesting, A; Kranke, F; Sch"onhof, M; Treiber, M; Helbing, Dirk; Kesting, Arne; Kranke, Florian; Sch\\"onhof, Martin; Treiber, Martin

    2006-01-01

    Adaptive-Cruise Control (ACC) automatically accelerates or decelerates a vehicle to maintain a selected time gap, to reach a desired velocity, or to prevent a rear-end collision. To this end, the ACC sensors detect and track the vehicle ahead for measuring the actual distance and speed difference. Together with the own velocity, these input variables are exactly the same as in car-following models. The focus of this contribution is: What will be the impact of a spreading of ACC systems on the traffic dynamics? Do automated driving strategies have the potential to improve the capacity and stability of traffic flow or will they necessarily increase the heterogeneity and instability? How does the result depend on the ACC equipment level? We discuss microscopic modeling aspects for human and automated (ACC) driving. By means of microscopic traffic simulations, we study how a variable percentage of ACC-equipped vehicles influences the stability of traffic flow, the maximum flow under free traffic conditions until ...

  3. SMART VIDEO SURVEILLANCE SYSTEM FOR VEHICLE DETECTION AND TRAFFIC FLOW CONTROL

    Directory of Open Access Journals (Sweden)

    A. A. SHAFIE

    2011-08-01

    Full Text Available Traffic signal light can be optimized using vehicle flow statistics obtained by Smart Video Surveillance Software (SVSS. This research focuses on efficient traffic control system by detecting and counting the vehicle numbers at various times and locations. At present, one of the biggest problems in the main city in any country is the traffic jam during office hour and office break hour. Sometimes it can be seen that the traffic signal green light is still ON even though there is no vehicle coming. Similarly, it is also observed that long queues of vehicles are waiting even though the road is empty due to traffic signal light selection without proper investigation on vehicle flow. This can be handled by adjusting the vehicle passing time implementing by our developed SVSS. A number of experiment results of vehicle flows are discussed in this research graphically in order to test the feasibility of the developed system. Finally, adoptive background model is proposed in SVSS in order to successfully detect target objects such as motor bike, car, bus, etc.

  4. A safety assessment methodology applied to CNS/ATM-based air traffic control system

    Energy Technology Data Exchange (ETDEWEB)

    Vismari, Lucio Flavio, E-mail: lucio.vismari@usp.b [Safety Analysis Group (GAS), School of Engineering at University of Sao Paulo (Poli-USP), Av. Prof. Luciano Gualberto, Trav.3, n.158, Predio da Engenharia de Eletricidade, Sala C2-32, CEP 05508-900, Sao Paulo (Brazil); Batista Camargo Junior, Joao, E-mail: joaocamargo@usp.b [Safety Analysis Group (GAS), School of Engineering at University of Sao Paulo (Poli-USP), Av. Prof. Luciano Gualberto, Trav.3, n.158, Predio da Engenharia de Eletricidade, Sala C2-32, CEP 05508-900, Sao Paulo (Brazil)

    2011-07-15

    In the last decades, the air traffic system has been changing to adapt itself to new social demands, mainly the safe growth of worldwide traffic capacity. Those changes are ruled by the Communication, Navigation, Surveillance/Air Traffic Management (CNS/ATM) paradigm , based on digital communication technologies (mainly satellites) as a way of improving communication, surveillance, navigation and air traffic management services. However, CNS/ATM poses new challenges and needs, mainly related to the safety assessment process. In face of these new challenges, and considering the main characteristics of the CNS/ATM, a methodology is proposed at this work by combining 'absolute' and 'relative' safety assessment methods adopted by the International Civil Aviation Organization (ICAO) in ICAO Doc.9689 , using Fluid Stochastic Petri Nets (FSPN) as the modeling formalism, and compares the safety metrics estimated from the simulation of both the proposed (in analysis) and the legacy system models. To demonstrate its usefulness, the proposed methodology was applied to the 'Automatic Dependent Surveillance-Broadcasting' (ADS-B) based air traffic control system. As conclusions, the proposed methodology assured to assess CNS/ATM system safety properties, in which FSPN formalism provides important modeling capabilities, and discrete event simulation allowing the estimation of the desired safety metric.

  5. Value sensitive design of automated workload distribution support for traffic control teams

    NARCIS (Netherlands)

    Harbers, M.; Neerincx, M.A.

    2014-01-01

    This paper studies the effects of automated support for workload distribution in traffic control teams on human values such as security, autonomy and privacy. The paper describes a workshop in which the support system's stakeholders, their values, and the effects of the support system on these value

  6. Dynamic traffic grooming in distributed-controlled IP/WDM optical mesh networks

    Institute of Scientific and Technical Information of China (English)

    Huang Jun; Zeng Qingji; Liu Jimin; Xiao Pengcheng; Liu Hua; Xiao Shilin

    2005-01-01

    In this paper, the study was devoted to the traffic-grooming problem in a distributed-controlled WDM mesh network. We studied the optimization of the maximal number of ports configured at each node in the network. We gave the maximumnumber simulation results in different network environment, which could be taken as a reference for network design.

  7. Expertise differences in air traffic control: An eye-tracking study

    NARCIS (Netherlands)

    Van Meeuwen, Ludo; Jarodzka, Halszka; Brand-Gruwel, Saskia; Kirschner, Paul A.; De Bock, Jeano; Van Merriënboer, Jeroen

    2012-01-01

    Van Meeuwen, L. W., Jarodzka, H., Brand-Gruwel, S., Kirschner, P. A., De Bock, J. J. P. R., & Van Merriënboer, J. J. G. (2012, April). Expertise differences in air traffic control: An eye-tracking study. Paper presented at the American Educational Research Association Annual Meeting 2012, Vancouver,

  8. Building the Brain's "Air Traffic Control" System: How Early Experiences Shape the Development of Executive Function. Working Paper 11

    Science.gov (United States)

    National Scientific Council on the Developing Child, 2011

    2011-01-01

    Being able to focus, hold, and work with information in mind, filter distractions, and switch gears is like having an air traffic control system at a busy airport to manage the arrivals and departures of dozens of planes on multiple runways. In the brain, this air traffic control mechanism is called executive functioning, a group of skills that…

  9. Blurred controlling of crossroads traffic light%十字路口交通灯的模糊控制

    Institute of Scientific and Technical Information of China (English)

    张颖霄

    2009-01-01

    we could control the crossroads traffic light by blur,to solve the situation of crowded traffic in traditional controlling%通过对十字路口交通灯的模糊控制,解决了在传统控制中出现的交通堵塞情况.

  10. Final Environmental Assessment, Construction and Operation of Air Traffic Control Tower

    Science.gov (United States)

    2008-05-12

    Existing Control Tower Site. Complete demolition of the Control Tower building on the site would produce waste concrete, asphalt , metal, and wood...Construction & Operation of Air Traffic Control Tower 44 May 12, 2008 receptor elements. Workers would wear ear protection, as necessary, for...appear to be achieving their hazardous waste reduction goals. The major areas not meeting goals appear to be abrasive blasting and industrial

  11. Landing-Time-Controlled Management Of Air Traffic

    Science.gov (United States)

    Erzberger, Heinz; Tobias, Leonard

    1988-01-01

    Conceptual system controls aircraft with old and new guidance equipment. Report begins with overview of concept, then reviews controller-interactive simulations. Describes fuel-conservative-trajectory algorithm, based on equations of motion for controlling landing time. Finally, presents results of piloted simulations.

  12. A Teamwork-Oriented Air Traffic Control Simulator

    Science.gov (United States)

    2006-06-01

    capability to train the controller and/or controller team. Neophyte controllers can be given the chance to develop without any attendant fear of the...the increasing use of the shared airspace, especially in Europe where the density of industrialized countries is high and the shared airspace is

  13. 4D Trajectory Estimation for Air Traffic Control Automation System Based on Hybrid System Theory

    Directory of Open Access Journals (Sweden)

    Xin-Min Tang

    2012-03-01

    Full Text Available To resolve the problem of future airspace management under great traffic flow and high density condition, 4D trajectory estimation has become one of the core technologies of the next new generation air traffic control automation system. According to the flight profile and the dynamics models of different aircraft types under different flight conditions, a hybrid system model that switches the aircraft from one flight stage to another with aircraft state changing continuously in one state is constructed. Additionally, air temperature and wind speed are used to modify aircraft true airspeed as well as ground speed, and the hybrid system evolution simulation is used to estimate aircraft 4D trajectory. The case study proves that 4D trajectory estimated through hybrid system model can image the flight dynamic states of aircraft and satisfy the needs of the planned flight altitude profile.KEY WORDSair traffic management, 4D trajectory estimation, hybrid system model, aircraft dynamic model

  14. Dynamic Traffic Control Model Based on Traffic Environmental Capacity%基于交通环境容量的区域交通动态调控模型

    Institute of Scientific and Technical Information of China (English)

    杜怡曼; 贾宇涵; 吴建平; 许明; 杨森炎

    2015-01-01

    近年来,随着社会经济的发展,交通运输系统已经成为一个主要的空气污染源。为了保护城市空气质量,同时尽量满足居民的出行需求,应该把控制机动车排放和改善道路通行效率结合起来考虑。针对此问题,本文引入交通环境容量和宏观交通基本图,采用多目标规划模型来描述区域机动车排放和路网通行能力之间的关系,并通过动态交通调控机制降低重点区域内的交通排放总量。本文将该调控理论应用于南京某路网的管理过程中,仿真结果显示,交通环境控制效果比较显著,同时道路通行能力也得到一定程度的保证。文中相关的理论与实践,可以为城市区域交通管理和污染控制提供重要参考。%In recent years, transportation system has become an important source of air pollution. As a result, it is urgent to consider improving traffic efficiency under the condition of protecting urban air quality. Based on the traffic environmental capacity and macroscopic fundamental diagram theory, the multi-objective programming model is adopted to describe the relationship between traffic emission and traffic capacity. Then a dynamic traffic volume control method is developed for regional traffic management. As a case study, the proposed methodology is applied to a road network located in central area of Nanjing. The results show that traffic efficiency is improved significantly and the urban air quality is ensured. This paper can offer some reference for the decision-making of urban traffic management.

  15. A novel solution for car traffic control based on radiometric microwave devices

    Science.gov (United States)

    Soldovieri, Francesco; Denisov, Alexander; Speziale, Victor

    2014-05-01

    The significant problem of traffic in big cities, connected with huge and building up quantity of automobile cars, demands for novel strategies, based on nonconventional solutions, in order to improve system traffic control, especially at crossroads. As well known, the usual solution is based on the time relay, which requires the installation of a fixed traffic interval (signal light switching) at a crossroad; this solution is low cost, but does not account for the actual traffic conditions. Therefore, in the recent years, attention is towards to new designs, where the monitoring of the and control of traffic is carried out by using various methods including, optical, the infrared, magnetic, radar tracking, acoustical ones. In this work, we discuss the deployment of high sensitivity radiometric systems and radiometers(sensor) in the microwave range [1, 2]. In fact, the radiometer as "sensor" can provide an always updated information about the car traffic in any weather condition and in absence or low visibility conditions. In fact, the radiometric sensor detects the cars thanks to the different behavior of the car roofs which reflect the cold sky whereas the road asphalt is visible as warm object (at around outside temperature). [1] A. G. Denisov, V. P. Gorishnyak, S. E. Kuzmin et al., "Some experiments concerning resolution of 32 sensors passive 8mm wave imaging system," in Proceedings of the International Symposium on Space Terahertz Technology (ISSTT '09), Charlottesville, Va, USA, April 2009. [2] F. Soldovieri, A. Natale, V. Gorishnyak, A. Pavluchenko, A. Denisov, and L. Chen, "Radiometric Imaging for Monitoring and Surveillance Issues," International Journal of Antennas and Propagation, vol. 2013, Article ID 272561, 8 pages, 2013. doi:10.1155/2013/272561.

  16. Robust control tools for traffic monitoring in TCP/AQM networks

    CERN Document Server

    Ariba, Yassine; Rahme, Sandy; Labit, Yann

    2009-01-01

    Several studies have considered control theory tools for traffic control in communication networks, as for example the congestion control issue in IP (Internet Protocol) routers. In this paper, we propose to design a linear observer for time-delay systems to address the traffic monitoring issue in TCP/AQM (Transmission Control Protocol/Active Queue Management) networks. Due to several propagation delays and the queueing delay, the set TCP/AQM is modeled as a multiple delayed system of a particular form. Hence, appropriate robust control tools as quadratic separation are adopted to construct a delay dependent observer for TCP flows estimation. Note that, the developed mechanism enables also the anomaly detection issue for a class of DoS (Denial of Service) attacks. At last, simulations via the network simulator NS-2 and an emulation experiment validate the proposed methodology.

  17. Effects of traffic control on the soil physical quality and the cultivation of sugarcane

    Directory of Open Access Journals (Sweden)

    Gustavo Soares de Souza

    2014-02-01

    Full Text Available The cultivation of sugarcane with intensive use of machinery, especially for harvest, induces soil compaction, affecting the crop development. The control of agricultural traffic is an alternative of management in the sector, with a view to preserve the soil physical quality, resulting in increased sugarcane root growth, productivity and technological quality. The objective of this study was to evaluate the physical quality of an Oxisol with and without control traffic and the resulting effects on sugarcane root development, productivity and technological quality. The following managements were tested: no traffic control (NTC, traffic control consisting of an adjustment of the track width of the tractor and sugarcane trailer (TC1 and traffic control consisting of an adjustment of the track width of the tractor and trailer and use of an autopilot (TC2. Soil samples were collected (layers 0.00-0.10; 0.10-0.20 and 0.20-0.30 m in the plant rows, inter-row center and seedbed region, 0.30 m away from the plant row. The productivity was measured with a specific weighing scale. The technological variables of sugarcane were measured in each plot. Soil cores were collected to analyze the root system. In TC2, the soil bulk density and compaction degree were lowest and total porosity and macroporosity highest in the plant row. Soil penetration resistance in the plant row, was less than 2 MPa in TC1 and TC2. Soil aggregation and total organic carbon did not differ between the management systems. The root surface and volume were increased in TC1 and TC2, with higher productivity and sugar yield than under NTC. The sugarcane variables did not differ between the managements. The soil physical quality in the plant row was preserved under management TC1 and TC2, with an improved root development and increases of 18.72 and 20.29 % in productivity and sugar yield, respectively.

  18. Environmental risk factors contributing to traffic accidents in children: a case-control study.

    Science.gov (United States)

    Jamshidi, Ensiyeh; Moradi, Ali; Majdzadeh, Reza

    2016-06-09

    The aim of this study is to identify environmental risk factors related to road accidents in children of Tehran. This case-control study was performed in 2013. The cases were injured pedestrians aged 5-15 who were admitted to major hospitals supervised by Tehran University of Medical Sciences. The sample size for the cases was 273 and for the control group was 546. For the completeness of the clusters, 7 extra persons in case (total = 280) and 14 persons (total = 560) in control group were included. The interference of confounding variables assessed through forward conditional logistic regression. Result shows occurrence of traffic accidents was significantly associate with the width of the alleys or (traffic congestion (OR = 4.1, 95% CI: 2.6-6.4), traffic speed (OR = 2.1, 95% CI: 1.3-3.2) and existence of pedestrian bridges(OR = 4.2, 95% CI: 2.6-6.8). In the light of the important role of environmental factors in the occurrence of child traffic accidents, alleviating structural risk factors in addition to education and enforcement need more systematic efforts and planning by policymakers and urban planners to attain pedestrian safety goals.

  19. Controlled traffic and soil physical quality of an Oxisol under sugarcane cultivation

    Directory of Open Access Journals (Sweden)

    Gustavo Soares de Souza

    2015-06-01

    Full Text Available Machinery traffic in sugarcane (Saccharumsp. plantations reduces soil physical quality, and hinders both root development and crop yield. We evaluated the physical quality of an Oxisol and the development of sugarcane roots under controlled traffic. The treatments assessed were: without controlled machinery traffic (WCT, controlled traffic by adjusting the tractor and infield wagons to a 3.0 m track width with the operator guiding the machinery (CT1 and the previous treatment using real time kinematic / global positioning system (RTK / GPS precision auto steer (CT2. Soil samples were collected from the planting rows, seedbed and inter-row center to determine the least limiting water range (LLWR and soil porosity from scanned 2-D images. The root dry mass was sampled from monoliths, separated from the soil by washing through a 2-mm sieve and dried in an oven. A higher LLWR was observed in the planting row under CT1 and CT2 than under WCT. The planting row had a predominance of complex pores with a diameter > 500 µm in the 0.15-0.27 m depth layer under CT1 and CT2. In the planting rows under WCT, the root dry mass was only 44 % of that measured under CT2. Benefits regarding soil physical quality and growth roots were observed when the tractor-wagon track width was adjusted based on the sugarcane spacing using either precision auto steering or manual operation of the machinery.

  20. Effects of Automation Types on Air Traffic Controller Situation Awareness and Performance

    Science.gov (United States)

    Sethumadhavan, A.

    2009-01-01

    The Joint Planning and Development Office has proposed the introduction of automated systems to help air traffic controllers handle the increasing volume of air traffic in the next two decades (JPDO, 2007). Because fully automated systems leave operators out of the decision-making loop (e.g., Billings, 1991), it is important to determine the right level and type of automation that will keep air traffic controllers in the loop. This study examined the differences in the situation awareness (SA) and collision detection performance of individuals when they worked with information acquisition, information analysis, decision and action selection and action implementation automation to control air traffic (Parasuraman, Sheridan, & Wickens, 2000). When the automation was unreliable, the time taken to detect an upcoming collision was significantly longer for all the automation types compared with the information acquisition automation. This poor performance following automation failure was mediated by SA, with lower SA yielding poor performance. Thus, the costs associated with automation failure are greater when automation is applied to higher order stages of information processing. Results have practical implications for automation design and development of SA training programs.

  1. Optimal traffic control in highway transportation networks using linear programming

    KAUST Repository

    Li, Yanning

    2014-06-01

    This article presents a framework for the optimal control of boundary flows on transportation networks. The state of the system is modeled by a first order scalar conservation law (Lighthill-Whitham-Richards PDE). Based on an equivalent formulation of the Hamilton-Jacobi PDE, the problem of controlling the state of the system on a network link in a finite horizon can be posed as a Linear Program. Assuming all intersections in the network are controllable, we show that the optimization approach can be extended to an arbitrary transportation network, preserving linear constraints. Unlike previously investigated transportation network control schemes, this framework leverages the intrinsic properties of the Halmilton-Jacobi equation, and does not require any discretization or boolean variables on the link. Hence this framework is very computational efficient and provides the globally optimal solution. The feasibility of this framework is illustrated by an on-ramp metering control example.

  2. Real-time optical path control method that utilizes multiple support vector machines for traffic prediction

    Science.gov (United States)

    Kawase, Hiroshi; Mori, Yojiro; Hasegawa, Hiroshi; Sato, Ken-ichi

    2016-02-01

    An effective solution to the continuous Internet traffic expansion is to offload traffic to lower layers such as the L2 or L1 optical layers. One possible approach is to introduce dynamic optical path operations such as adaptive establishment/tear down according to traffic variation. Path operations cannot be done instantaneously; hence, traffic prediction is essential. Conventional prediction techniques need optimal parameter values to be determined in advance by averaging long-term variations from the past. However, this does not allow adaptation to the ever-changing short-term variations expected to be common in future networks. In this paper, we propose a real-time optical path control method based on a machinelearning technique involving support vector machines (SVMs). A SVM learns the most recent traffic characteristics, and so enables better adaptation to temporal traffic variations than conventional techniques. The difficulty lies in determining how to minimize the time gap between optical path operation and buffer management at the originating points of those paths. The gap makes the required learning data set enormous and the learning process costly. To resolve the problem, we propose the adoption of multiple SVMs running in parallel, trained with non-overlapping subsets of the original data set. The maximum value of the outputs of these SVMs will be the estimated number of necessary paths. Numerical experiments prove that our proposed method outperforms a conventional prediction method, the autoregressive moving average method with optimal parameter values determined by Akaike's information criterion, and reduces the packet-loss ratio by up to 98%.

  3. Illuminating traffic control for cell-division planes.

    Science.gov (United States)

    Robatzek, Silke

    2014-01-01

    When a plant cell divides, four related proteins control the trafficking of vesicles and ensure that cargo that is normally recycled to the plasma membrane is instead re-routed to the plane of cell division.

  4. Splitting of Traffic Flows to Control Congestion in Special Events

    Directory of Open Access Journals (Sweden)

    Ciro D'Apice

    2011-01-01

    minimized with respect to the same control parameter. The obtained results have been tested by simulations of urban networks. Decongestion effects are also confirmed estimating the time a car needs to cross a fixed route on the network.

  5. Cellular metabolic and autophagic pathways: traffic control by redox signaling.

    Science.gov (United States)

    Dodson, Matthew; Darley-Usmar, Victor; Zhang, Jianhua

    2013-10-01

    It has been established that the key metabolic pathways of glycolysis and oxidative phosphorylation are intimately related to redox biology through control of cell signaling. Under physiological conditions glucose metabolism is linked to control of the NADH/NAD redox couple, as well as providing the major reductant, NADPH, for thiol-dependent antioxidant defenses. Retrograde signaling from the mitochondrion to the nucleus or cytosol controls cell growth and differentiation. Under pathological conditions mitochondria are targets for reactive oxygen and nitrogen species and are critical in controlling apoptotic cell death. At the interface of these metabolic pathways, the autophagy-lysosomal pathway functions to maintain mitochondrial quality and generally serves an important cytoprotective function. In this review we will discuss the autophagic response to reactive oxygen and nitrogen species that are generated from perturbations of cellular glucose metabolism and bioenergetic function.

  6. En Route/Terminal ATC (Air Traffic Control) Operations Concept.

    Science.gov (United States)

    1983-10-28

    been provided It is recognized that for events such as catastro - controllers interface phes, hi-jackings, or sensi- with pilots and control- tive U.S...idetiie .icat " nbokcd Tig ~ l ~ C nttt V. DrONe ~iy n ieto vco Itwddr lc’ PoutionSymbls tne mpced aeadof Wet)O~te w0b9f ,i29 6 Fre tack No ~i~t pln

  7. Heart Rate Variability as a Measure of Airport Ramp-Traffic Controllers Workload

    Science.gov (United States)

    Hayashi, Miwa; Dulchinos, Victoria Lee

    2016-01-01

    Heart Rate Variability (HRV) has been reported to reflect the person's cognitive and emotional stress levels, and may offer an objective measure of human-operator's workload levels, which are recorded continuously and unobtrusively to the task performance. The present paper compares the HRV data collected during a human-in-the-loop simulation of airport ramp-traffic control operations with the controller participants' own verbal self-reporting ratings of their workload.

  8. Modelling and optimization of computer network traffic controllers

    Directory of Open Access Journals (Sweden)

    N. U. Ahmed

    2005-01-01

    operation of the controller and evaluate the benefits of using a genetic algorithm approach to speed up the optimization process. Our results show that the use of the genetic algorithm proves particularly useful in reducing the computation time required to optimize the operation of a system consisting of multiple token-bucket-regulated sources.

  9. Detection of Botnet Command and Control Traffic in Enterprise Networks

    NARCIS (Netherlands)

    Burghouwt, P.

    2015-01-01

    Botnets play an important role in modern Internet-related cybercrime. A botnet consists of a group of infected computers, referred to as bots. The bots are remotely controlled and deployed in malicious activities, such as DDoS attacks, spam, and espionage. Clever design of the botnet C&C (Command an

  10. UAS Air Traffic Controller Acceptability Study-2: Effects of Communications Delays and Winds in Simulation

    Science.gov (United States)

    Comstock, James R., Jr.; Ghatas, Rania W.; Consiglio, Maria C.; Chamberlain, James P.; Hoffler, Keith D.

    2016-01-01

    This study evaluated the effects of Communications Delays and Winds on Air Traffic Controller ratings of acceptability of horizontal miss distances (HMDs) for encounters between UAS and manned aircraft in a simulation of the Dallas-Ft. Worth East-side airspace. Fourteen encounters per hour were staged in the presence of moderate background traffic. Seven recently retired controllers with experience at DFW served as subjects. Guidance provided to the UAS pilots for maintaining a given HMD was provided by information from self-separation algorithms displayed on the Multi-Aircraft Simulation System. Winds tested did not affect the acceptability ratings. Communications delays tested included 0, 400, 1200, and 1800 msec. For longer communications delays, there were changes in strategy and communications flow that were observed and reported by the controllers. The aim of this work is to provide useful information for guiding future rules and regulations applicable to flying UAS in the NAS.

  11. A control method for congested traffic induced by bottlenecks in the coupled map car-following model

    Science.gov (United States)

    Zhao, Xiaomei; Gao, Ziyou

    2006-07-01

    We present a simple control method to suppress the traffic congestion in the coupled map car-following model under open boundary, based on the pioneer work of Konishi et al. [Coupled map car-following model and its delayed-feedback control, Phys. Rev. E 60 (1999) 4000-4007]. Theoretically, it is proven that the congested traffic in the traffic system could be suppressed by using the method. Comparison between our method and the method of Konishi et al. is carried out. The simulation results show the temporal behavior obtained by our method is better than that by the method of Konishi et al., although both the methods can suppress the traffic jam. The simulation results demonstrate that the traffic system can move into a homogeneous phase and the flux has great increases by the introduction of the control signal. The simulation results are in good agreement with the theoretical analysis.

  12. 校园网流量分析与控制%Traffic Analysis and Control of Campus Network

    Institute of Scientific and Technical Information of China (English)

    林锡川; 李志强

    2011-01-01

    本文提出了一套校园网流量分析系统的基本架构,并探讨了控制校园网流量的可行方法.%This papper presents a traffic analysis system of campus network,and discusses a way to control network traffic.

  13. Potential of low ground pressure for harvesting machinery in a controlled traffic farming system in organic agriculture

    NARCIS (Netherlands)

    Vermeulen, G.D.; Sukkel, W.

    2008-01-01

    Seasonal controlled traffic farming (SCTF), i.e. CTF without using the permanent traffic lanes for harvesting and primary soil tillage, leads to improved soil structure, higher crop yields, significant reduction of the emission of nitrous oxide and increased uptake of methane. Improved timeliness of

  14. Remote Control Research in Central Africa

    OpenAIRE

    Trefon, Theodore; Cogels, Serge

    2009-01-01

    This article explains how a project being implemented in peri-urban central Africa is coordinated from an office in Brussels. After an overview that addresses the conceptual challenges of defining ‘peri-urban’ and the question of why these social spaces are important from a development perspective, the article outlines ‘remote control research’ step-by-step: (i) conceptualisation, (ii) identification and recruitment of local experts, (iii) selection of research sites, (iv) the process of form...

  15. Machine vision algorithms applied to dynamic traffic light control

    Directory of Open Access Journals (Sweden)

    Fabio Andrés Espinosa Valcárcel

    2013-01-01

    número de autos presentes en imágenes capturadas por un conjunto de cámaras estratégicamente ubicadas en cada intersección. Usando esta información, el sistema selecciona la secuencia de acciones que optimicen el flujo vehicular dentro de la zona de control, en un escenario simulado. Los resultados obtenidos muestran que el sistema disminuye en un 20% los tiempos de retraso para cada vehículo y que además es capaz de adaptarse rápida y eficientemente a los cambios de flujo.

  16. Structural controllability and controlling centrality of temporal networks.

    Science.gov (United States)

    Pan, Yujian; Li, Xiang

    2014-01-01

    Temporal networks are such networks where nodes and interactions may appear and disappear at various time scales. With the evidence of ubiquity of temporal networks in our economy, nature and society, it's urgent and significant to focus on its structural controllability as well as the corresponding characteristics, which nowadays is still an untouched topic. We develop graphic tools to study the structural controllability as well as its characteristics, identifying the intrinsic mechanism of the ability of individuals in controlling a dynamic and large-scale temporal network. Classifying temporal trees of a temporal network into different types, we give (both upper and lower) analytical bounds of the controlling centrality, which are verified by numerical simulations of both artificial and empirical temporal networks. We find that the positive relationship between aggregated degree and controlling centrality as well as the scale-free distribution of node's controlling centrality are virtually independent of the time scale and types of datasets, meaning the inherent robustness and heterogeneity of the controlling centrality of nodes within temporal networks.

  17. Using light to see and control membrane traffic.

    Science.gov (United States)

    Xu, Yingke; Melia, Thomas J; Toomre, Derek K

    2011-12-01

    Cellular compartmentalization into discrete organelles is maintained by membrane trafficking including vesiculation and tubulation. Recent advances in superresolution imaging have begun to bring these small and dynamic events into focus. Most nanoscopes exploit, and are limited by, switching dyes ON and OFF. Using ground state depletion to switch dyes into long-lived dark states can exploit specific photophysical properties of dyes, such as redox potential or pK(a), and expand the repertoire of nanoscopy probes for multicolor imaging. Seeing is not enough, and new technologies based on homodimerization, heterodimerization and selective release can manipulate membrane trafficking in pulse-chase and light-controlled ways. Herein we highlight the utility and promise of these strategies and discuss their current limitations.

  18. Traffic jam at adjustable tollgates controlled by line length

    Science.gov (United States)

    Nagatani, Takashi

    2016-01-01

    We present the stochastic model for the jam formation at the tollgates of which the number is adjusted by synchronizing with the jam's length. We study the jam formation and its fluctuation in front of the adjustable tollgates on a highway. Controlling the number of tollgates has an important effect on the jam formation. The jams are classified into three kinds: (a) localized jam, (b) synchronized jam, and (c) growing jam. The jamming transitions from the localized jam, through the synchronized jam, to the growing jam occur with increasing inflow probability. At an intermediate inflow, the jam fluctuates largely by synchronizing with the number of tollgates. When the inflow probability is higher than the sum of outflow probabilities at tollgates, the jam continues to grow and diverge with time. The dependence of the fluctuating jam on the inflow probability is clarified.

  19. Managing emergencies and abnormal situations in air traffic control (part II): teamwork strategies.

    Science.gov (United States)

    Malakis, Stathis; Kontogiannis, Tom; Kirwan, Barry

    2010-07-01

    Team performance has been studied in many safety-critical organizations including aviation, nuclear power plant, offshore oil platforms and health organizations. This study looks into teamwork strategies that air traffic controllers employ to manage emergencies and abnormal situations. Two field studies were carried out in the form of observations of simulator training in emergency and unusual scenarios of novices and experienced controllers. Teamwork strategies covered aspects of team orientation and coordination, information exchange, change management and error handling. Several performance metrics were used to rate the efficiency of teamwork and test the construct validity of a prototype model of teamwork. This is a companion study to an earlier investigation of taskwork strategies in the same field (part I) and contributes to the development of a generic model for Taskwork and Teamwork strategies in Emergencies in Air traffic Management (T(2)EAM). Suggestions are made on how to use T(2)EAM to develop training programs, assess team performance and improve mishap investigations.

  20. A Multiple Agent Model of Human Performance in Automated Air Traffic Control and Flight Management Operations

    Science.gov (United States)

    Corker, Kevin; Pisanich, Gregory; Condon, Gregory W. (Technical Monitor)

    1995-01-01

    A predictive model of human operator performance (flight crew and air traffic control (ATC)) has been developed and applied in order to evaluate the impact of automation developments in flight management and air traffic control. The model is used to predict the performance of a two person flight crew and the ATC operators generating and responding to clearances aided by the Center TRACON Automation System (CTAS). The purpose of the modeling is to support evaluation and design of automated aids for flight management and airspace management and to predict required changes in procedure both air and ground in response to advancing automation in both domains. Additional information is contained in the original extended abstract.

  1. Congestion Control Protocol for Wireless Sensor Networks Handling Prioritized Heterogeneous Traffic

    CERN Document Server

    Monowar, Muhammad Mostafa; Pathan, Al-Sakib Khan; Hong, Choong Seon

    2008-01-01

    Heterogeneous applications could be assimilated within the same wireless sensor network with the aid of modern motes that have multiple sensor boards on a single radio board. Different types of data generated from such types of motes might have different transmission characteristics in terms of priority, transmission rate, required bandwidth, tolerable packet loss, delay demands etc. Considering a sensor network consisting of such multi-purpose nodes, in this paper we propose Prioritized Heterogeneous Traffic-oriented Congestion Control Protocol (PHTCCP) which ensures efficient rate control for prioritized heterogeneous traffic. Our protocol uses intra-queue and inter-queue priorities for ensuring feasible transmission rates of heterogeneous data. It also guarantees efficient link utilization by using dynamic transmission rate adjustment. Detailed analysis and simulation results are presented along with the description of our protocol to demonstrate its effectiveness in handling prioritized heterogeneous traf...

  2. Development of a framework for the evaluation of the environmental benefits of controlled traffic farming

    OpenAIRE

    Mouazen, Abdul; Palmqvist, Martin

    2015-01-01

    Although controlled traffic farming (CTF) is an environmentally friendly soil management system, no quantitative evaluation of environmental benefits is available. This paper aims at establishing a framework for quantitative evaluation of the environmental benefits of CTF, considering a list of environmental benefits, namely, reducing soil compaction, runoff/erosion, energy requirement and greenhouse gas emission (GHG), conserving organic matter, enhancing soil biodiversity and fertiliser use...

  3. TRAFFIC CONTROL AND IMPROVING RELATIONS DRIVERS OF VEHICLES WITH EMPLOYEES UNITS GAI CITIES OF DNIPROPETROVSK

    OpenAIRE

    Мозолевич, Г. Я.; А. В. ТРОЯН

    2013-01-01

    In this work there were suggested the arrangements for the improvement of mutual relations of drivers and employees of the State motor-car inspection of Dnipropetrovsk city by introduction of electronic account of documents and automation of processes of travelling traffic regulation and controlling a travelling situation on the motor-car ways of city. There has been worked out strategy of introduction and expected cost of project for Dni-propetrovsk city. 

  4. Using Historical Data to Automatically Identify Air-Traffic Control Behavior

    Science.gov (United States)

    Lauderdale, Todd A.; Wu, Yuefeng; Tretto, Celeste

    2014-01-01

    This project seeks to develop statistical-based machine learning models to characterize the types of errors present when using current systems to predict future aircraft states. These models will be data-driven - based on large quantities of historical data. Once these models are developed, they will be used to infer situations in the historical data where an air-traffic controller intervened on an aircraft's route, even when there is no direct recording of this action.

  5. A Longitudinal Study of Myers-Briggs Personality Types in Air Traffic Controllers

    Science.gov (United States)

    2004-12-01

    designed to look at the role of personality types as defined by the Myers-Briggs Type Indicator ( MBTI ). The instrument assesses personality on four...investigated the relationship between MBTI types and initial success in the Air Traffic Control Academy Screen Program, subsequent field training...outcomes, and transition to a supervisory or managerial position about 20 years later. METHOD. The 300-item MBTI was administered to 5,588 males (87

  6. Traffic Monitor

    Science.gov (United States)

    1992-01-01

    Mestech's X-15 "Eye in the Sky," a traffic monitoring system, incorporates NASA imaging and robotic vision technology. A camera or "sensor box" is mounted in a housing. The sensor detects vehicles approaching an intersection and sends the information to a computer, which controls the traffic light according to the traffic rate. Jet Propulsion Laboratory technical support packages aided in the company's development of the system. The X-15's "smart highway" can also be used to count vehicles on a highway and compute the number in each lane and their speeds, important information for freeway control engineers. Additional applications are in airport and railroad operations. The system is intended to replace loop-type traffic detectors.

  7. A new intelligent approach for air traffic control using gravitational search algorithm

    Indian Academy of Sciences (India)

    Kazem Dastgerdi; Nasser Mehrshad; Mohsen Farshad

    2016-02-01

    Aircraft landing planning (ALP) is one of the most important challenging problems in the domain of air traffic control (ATC). Solving this NP-hard problem is a valuable aid in organizing air traffic in terminal control area (TCA), which itself leads to a decrease in aircraft fuel consumption, costs of airlines, and workload undertaken by air traffic controllers. In the present paper, the ALP problem is dealt with by applying effective rich knowledge to the optimization process (to remove obvious non-optimal solutions), and the first use of Gravitational Search Algorithm (GSA) in resolving such a case. In this regard, while the specific regulations for safe separation have been observed, the optimal landing time, the optimal runway, and the order of consecutive landings have been determined so that the main goal (minimizing total flight delays) would be best met. Results of simulations show that this approach, compared to previous ones, which are based on Genetic and Bionomic algorithms, GLS, and Scatter search method, considerably decreases total flight delays. Attaining zero in the total flight delays in three scenarios with real data shows that the suggested intelligent approach is more decisive than others in finding an optimal solution.

  8. Hematological and immunological effects of stress of air traffic controllers in northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Valdenilson Ribeiro Ribas

    2011-06-01

    Full Text Available BACKGROUND: Several studies have shown that stress and emotional reactions can affect immune responses in animals and humans. OBJECTIVE: The aim of this study was to evaluate hematological and immunological effects of stress on air traffic controllers. METHODS: Thirty air traffic controllers and 15 aeronautical information service operators were evaluated. The groups were divided as information service operators with 10 years or more of experience (AIS>10 and with less than 10 years in the profession (AIS10 and with less than 10 years in the profession (ATCo10 group presented a significantly lower phagocytosis rate of monocytes at 2:00 p.m. compared to 8:00 a.m. Moreover, the ATCo>10 group presented lower hemoglobin, mean corpuscular hemoglobin concentration, platelet and leukocyte levels, and increased cortisol concentrations at 8:00 a.m. compared to the other groups. Additionally, this group had lower phagocytosis rate of monocytes, and hemoglobin, platelet, leukocyte, basophils and nitric oxide levels at 2:00 p.m. compared to the other groups. CONCLUSION: Stress seems to greatly affect immune responses of air traffic controllers with more than ten years of experience.

  9. SIMULATION MODELS OF HEAVY TRUCKS TRAFFIC CONTROL WITH ELECTRIC DC DRIVE

    Directory of Open Access Journals (Sweden)

    N. N. Hurski

    2015-01-01

    Full Text Available A model of the straight course of movement of the mobile machine with a traction electric motor DC. Traffic management controller provides a closed classical scheme with feedback. The mathematical model of the electric DC motor with the energy dissipation in the rotor bearings. Design scheme of mobile machines include speed dial controller, traction electric motor, gearbox, transmission and progressively moving mass on the elastic­dissipative wheel. The results of the simulation of the machine in the form of temporary processes of change control signals, voltage and current in the windings of the motor and traction power developed on the wheel.

  10. 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...

  11. Admission Control for Multiservices Traffic in Hierarchical Mobile IPv6 Networks by Using Fuzzy Inference System

    Directory of Open Access Journals (Sweden)

    Jung-Shyr Wu

    2012-01-01

    Full Text Available CAC (Call Admission Control plays a significant role in providing QoS (Quality of Service in mobile wireless networks. In addition to much research that focuses on modified Mobile IP to get better efficient handover performance, CAC should be introduced to Mobile IP-based network to guarantee the QoS for users. In this paper, we propose a CAC scheme which incorporates multiple traffic types and adjusts the admission threshold dynamically using fuzzy control logic to achieve better usage of resources. The method can provide QoS in Mobile IPv6 networks with few modifications on MAP (Mobility Anchor Point functionality and slight change in BU (Binding Update message formats. According to the simulation results, the proposed scheme presents good performance of voice and video traffic at the expenses of poor performance on data traffic. It is evident that these CAC schemes can reduce the probability of the handoff dropping and the cell overload and limit the probability of the new call blocking.

  12. The Sybtraps: control of synaptobrevin traffic by synaptophysin, α-synuclein and AP-180.

    Science.gov (United States)

    Gordon, Sarah L; Cousin, Michael A

    2014-03-01

    Synaptobrevin II (sybII) is a key fusogenic molecule on synaptic vesicles (SVs) therefore the active maintenance of both its conformation and location in sufficient numbers on this organelle is critical in both mediating and sustaining neurotransmitter release. Recently three proteins have been identified having key roles in the presentation, trafficking and retrieval of sybII during the fusion and endocytosis of SVs. The nerve terminal protein α-synuclein catalyses sybII entry into SNARE complexes, whereas the monomeric adaptor protein AP-180 is required for sybII retrieval during SV endocytosis. Overarching these events is the tetraspan SV protein synaptophysin, which is a major sybII interaction partner on the SV. This review will evaluate recent studies to propose working models for the control of sybII traffic by synaptophysin and other Sybtraps (sybII trafficking partners) and suggest how dysfunction in sybII traffic may contribute to human disease.

  13. Airborne Four-Dimensional Flight Management in a Time-based Air Traffic Control Environment

    Science.gov (United States)

    Williams, David H.; Green, Steven M.

    1991-01-01

    Advanced Air Traffic Control (ATC) systems are being developed which contain time-based (4D) trajectory predictions of aircraft. Airborne flight management systems (FMS) exist or are being developed with similar 4D trajectory generation capabilities. Differences between the ATC generated profiles and those generated by the airborne 4D FMS may introduce system problems. A simulation experiment was conducted to explore integration of a 4D equipped aircraft into a 4D ATC system. The NASA Langley Transport Systems Research Vehicle cockpit simulator was linked in real time to the NASA Ames Descent Advisor ATC simulation for this effort. Candidate procedures for handling 4D equipped aircraft were devised and traffic scenarios established which required time delays absorbed through speed control alone or in combination with path stretching. Dissimilarities in 4D speed strategies between airborne and ATC generated trajectories were tested in these scenarios. The 4D procedures and FMS operation were well received by airline pilot test subjects, who achieved an arrival accuracy at the metering fix of 2.9 seconds standard deviation time error. The amount and nature of the information transmitted during a time clearance were found to be somewhat of a problem using the voice radio communication channel. Dissimilarities between airborne and ATC-generated speed strategies were found to be a problem when the traffic remained on established routes. It was more efficient for 4D equipped aircraft to fly trajectories with similar, though less fuel efficient, speeds which conform to the ATC strategy. Heavy traffic conditions, where time delays forced off-route path stretching, were found to produce a potential operational benefit of the airborne 4D FMS.

  14. Automated Air Traffic Control Operations with Weather and Time-Constraints: A First Look at (Simulated) Far-Term Control Room Operations

    Science.gov (United States)

    Prevot, Thomas; Homola, Jeffrey R.; Martin, Lynne H.; Mercer, Joey S.; Cabrall, Christopher C.

    2011-01-01

    In this paper we discuss results from a recent high fidelity simulation of air traffic control operations with automated separation assurance in the presence of weather and time-constraints. We report findings from a human-in-the-loop study conducted in the Airspace Operations Laboratory (AOL) at the NASA Ames Research Center. During four afternoons in early 2010, fifteen active and recently retired air traffic controllers and supervisors controlled high levels of traffic in a highly automated environment during three-hour long scenarios, For each scenario, twelve air traffic controllers operated eight sector positions in two air traffic control areas and were supervised by three front line managers, Controllers worked one-hour shifts, were relieved by other controllers, took a 3D-minute break, and worked another one-hour shift. On average, twice today's traffic density was simulated with more than 2200 aircraft per traffic scenario. The scenarios were designed to create peaks and valleys in traffic density, growing and decaying convective weather areas, and expose controllers to heavy and light metering conditions. This design enabled an initial look at a broad spectrum of workload, challenge, boredom, and fatigue in an otherwise uncharted territory of future operations. In this paper we report human/system integration aspects, safety and efficiency results as well as airspace throughput, workload, and operational acceptability. We conclude that, with further refinements. air traffic control operations with ground-based automated separation assurance can be an effective and acceptable means to routinely provide very high traffic throughput in the en route airspace.

  15. Localization and recognition of traffic signs for automated vehicle control systems

    Science.gov (United States)

    Zadeh, Mahmoud M.; Kasvand, T.; Suen, Ching Y.

    1998-01-01

    We present a computer vision system for detection and recognition of traffic signs. Such systems are required to assist drivers and for guidance and control of autonomous vehicles on roads and city streets. For experiments we use sequences of digitized photographs and off-line analysis. The system contains four stages. First, region segmentation based on color pixel classification called SRSM. SRSM limits the search to regions of interest in the scene. Second, we use edge tracing to find parts of outer edges of signs which are circular or straight, corresponding to the geometrical shapes of traffic signs. The third step is geometrical analysis of the outer edge and preliminary recognition of each candidate region, which may be a potential traffic sign. The final step in recognition uses color combinations within each region and model matching. This system maybe used for recognition of other types of objects, provided that the geometrical shape and color content remain reasonably constant. The method is reliable, easy to implement, and fast, This differs form the road signs recognition method in the PROMETEUS. The overall structure of the approach is sketched.

  16. An RFID-Based Intelligent Vehicle Speed Controller Using Active Traffic Signals

    Directory of Open Access Journals (Sweden)

    Joshué Pérez

    2010-06-01

    Full Text Available These days, mass-produced vehicles benefit from research on Intelligent Transportation System (ITS. One prime example of ITS is vehicle Cruise Control (CC, which allows it to maintain a pre-defined reference speed, to economize on fuel or energy consumption, to avoid speeding fines, or to focus all of the driver’s attention on the steering of the vehicle. However, achieving efficient Cruise Control is not easy in roads or urban streets where sudden changes of the speed limit can happen, due to the presence of unexpected obstacles or maintenance work, causing, in inattentive drivers, traffic accidents. In this communication we present a new Infrastructure to Vehicles (I2V communication and control system for intelligent speed control, which is based upon Radio Frequency Identification (RFID technology for identification of traffic signals on the road, and high accuracy vehicle speed measurement with a Hall effect-based sensor. A fuzzy logic controller, based on sensor fusion of the information provided by the I2V infrastructure, allows the efficient adaptation of the speed of the vehicle to the circumstances of the road. The performance of the system is checked empirically, with promising results.

  17. An RFID-based intelligent vehicle speed controller using active traffic signals.

    Science.gov (United States)

    Pérez, Joshué; Seco, Fernando; Milanés, Vicente; Jiménez, Antonio; Díaz, Julio C; de Pedro, Teresa

    2010-01-01

    These days, mass-produced vehicles benefit from research on Intelligent Transportation System (ITS). One prime example of ITS is vehicle Cruise Control (CC), which allows it to maintain a pre-defined reference speed, to economize on fuel or energy consumption, to avoid speeding fines, or to focus all of the driver's attention on the steering of the vehicle. However, achieving efficient Cruise Control is not easy in roads or urban streets where sudden changes of the speed limit can happen, due to the presence of unexpected obstacles or maintenance work, causing, in inattentive drivers, traffic accidents. In this communication we present a new Infrastructure to Vehicles (I2V) communication and control system for intelligent speed control, which is based upon Radio Frequency Identification (RFID) technology for identification of traffic signals on the road, and high accuracy vehicle speed measurement with a Hall effect-based sensor. A fuzzy logic controller, based on sensor fusion of the information provided by the I2V infrastructure, allows the efficient adaptation of the speed of the vehicle to the circumstances of the road. The performance of the system is checked empirically, with promising results.

  18. Traffic control based on dahlin algorithm and neural network prediction in TAM networks

    Institute of Scientific and Technical Information of China (English)

    沈伟; 冯瑞; 邵惠鹤

    2004-01-01

    The propagation delay in networks has a great adverse effect on rate-based traffic control. This paper proposes the composite control based on Dab lin algorithm feedback control and neural network feedforward predictive compensation online for ABR (available bit rate) communication in ATM (asynchronous transfer mode) networks, which can overcome the adverse effect caused by the delay on the control rapidity and stability better. The theoretical analysis and simulation research show that the scheme can make sources respond to the changes of network status rapidly, avoid the congestion effectively and utilize the bandwidth sufficiently. Compared with PID (proportional-integral-derivative) control, cell loss rate is much lower, link utilization rate is much higher, and required buffer capacity is much smaller.

  19. IMPROVING PERFORMANCE OF IEEE 802.11 BY A DYNAMIC CONTROL BACKOFF ALGORITHM UNDER UNSATURATED TRAFFIC LOADS

    Directory of Open Access Journals (Sweden)

    Hatm Alkadeki

    2015-12-01

    Full Text Available The IEEE 802.11 backoff algorithm is very important for controlling system throughput over contentionbased wireless networks. For this reason, there are many studies on wireless network performance focus on developing backoff algorithms. However, most existing models are based on saturated traffic loads, which are not a real representation of actual network conditions. In this paper, a dynamic control backoff time algorithm is proposed to enhance both delay and throughput performance of the IEEE 802.11 distributed coordination function. This algorithm considers the distinction between high and low traffic loads in order to deal with unsaturated traffic load conditions. In particular, the equilibrium point analysis model is used to represent the algorithm under various traffic load conditions. Results of extensive simulation experiments illustrate that the proposed algorithm yields better performance throughput and a better average transmission packet delay than related algorithms.

  20. Analysing adjustment factors for using lanes at traffic-light-controlled intersections in Bogotá, Colombia.

    Directory of Open Access Journals (Sweden)

    Ricardo José Peña Lindarte

    2010-05-01

    Full Text Available This article was focused on analyzing the lane use adjustment factor (fLU forming one of the eleven adjustment factors proposed in the current calculation methodology contained in the 2000 version of the Transportation Research Board’s (TRB Highway Capacity Manual (HCM for analyzing traffic-light-controlled intersection capacity in terms of saturation intensity. A methodology was established when analyzing the fLU factor that considered operational conditions regarding traffic-light-controlled intersections in Bogota. Road traffic flows were analyzed, including characterizing road traffic based on statistical sampling, field data collection and analysis. The project proposed equations allowing reference values to be gathered for determining adjustment factors regarding lane use on roads in Bogota in relation to existing access typologies and road traffic volume for analyzing traffic-light- controlled intersections. For example, in the specific case of roads having direct double-lane access (2CCD, the basic equation was determined to be y=-3,03E-08X2+3,44E-05X+0,888988, having a 1.0 coefficient of correlation. The dependent variable y referred to the fLU factor and the independent variable X was the volume of road traffic in mixed vehicles/hour. This equation was considered to be statistically relevant. A comparative analysis of the lane use adjustment factors estimated in the project is also presented and compared to the values recommended by the US Highway Capacity Manual. The project’s conclusions and re- commendations were thus sustained, validating the recommended factors summarized by the HCM and recommending that the results obtained from the project should be used in traffic-light-controlled design and planning projects.

  1. Multiagent Systems: Introduction and Application in Traffic Control and Simulation and Emergency Situations Simulation

    Directory of Open Access Journals (Sweden)

    BAZZAN, A. L. C.

    2010-12-01

    Full Text Available The area of multiagent systems is new and challenging. From the moment a system includes more than one agent, artificial intelligence techniques become inadequate for they do not consider interactions with other agent, need for coordination and other factors. In this text those aspects are discussed, and an introduction to the area of autonomous agents and multiagent systems is offered. Afterwards, two application of this kind of systems are described, both in the area of transportation and emergency sistuations. In the former we discuss traffic control and simulation and in the latter, we focus on the simulation tool RoboCup Rescue

  2. Impact of Operating Context on the Use of Structure in Air Traffic Controller Cognitive Processes

    Science.gov (United States)

    Davison, Hayley J.; Histon, Jonathan M.; Ragnarsdottir, Margret Dora; Major, Laura M.; Hansman, R. John

    2004-01-01

    This paper investigates the influence of structure on air traffic controllers cognitive processes in the TRACON, En Route, and Oceanic environments. Radar data and voice command analyses were conducted to support hypotheses generated through observations and interviews conducted at the various facilities. Three general types of structure-based abstractions (standard flows, groupings, and critical points) have been identified as being used in each context, though the details of their application varied in accordance with the constraints of the particular operational environment. Projection emerged as a key cognitive process aided by the structure-based abstractions, and there appears to be a significant difference between how time-based versus spatial-based projection is performed by controllers. It is recommended that consideration be given to the value provided by the structure-based abstractions to the controller as well as to maintain consistency between the type (time or spatial) of information support provided to the controller.

  3. Air Traffic Controllers’ Long-Term Speech-in-Noise Training Effects: A Control Group Study

    Science.gov (United States)

    Zaballos, María T.P.; Plasencia, Daniel P.; González, María L.Z.; de Miguel, Angel R.; Macías, Ángel R.

    2016-01-01

    Introduction: Speech perception in noise relies on the capacity of the auditory system to process complex sounds using sensory and cognitive skills. The possibility that these can be trained during adulthood is of special interest in auditory disorders, where speech in noise perception becomes compromised. Air traffic controllers (ATC) are constantly exposed to radio communication, a situation that seems to produce auditory learning. The objective of this study has been to quantify this effect. Subjects and Methods: 19 ATC and 19 normal hearing individuals underwent a speech in noise test with three signal to noise ratios: 5, 0 and −5 dB. Noise and speech were presented through two different loudspeakers in azimuth position. Speech tokes were presented at 65 dB SPL, while white noise files were at 60, 65 and 70 dB respectively. Results: Air traffic controllers outperform the control group in all conditions [Pcontrol group in all conditions. Thus, this study provides evidence that long-term auditory training is indeed useful in achieving better speech-in-noise understanding even in adverse conditions. PMID:27991470

  4. Evidence of traffic-related pollutant control in soil-based sustainable urban drainage systems (SUDS).

    Science.gov (United States)

    Napier, F; Jefferies, C; Heal, K V; Fogg, P; Arcy, B J D; Clarke, R

    2009-01-01

    SUDS are being increasingly employed to control highway runoff and have the potential to protect groundwater and surface water quality by minimising the risks of both point and diffuse sources of pollution. While these systems are effective at retaining polluted solids by filtration and sedimentation processes, less is known of the detail of pollutant behaviour within SUDS structures. This paper reports on investigations carried out as part of a co-ordinated programme of controlled studies and field measurements at soft-engineered SUDS undertaken in the UK, observing the accumulation and behaviour of traffic-related heavy metals, oil and PAHs. The field data presented were collected from two extended detention basins serving the M74 motorway in the south-west of Scotland. Additional data were supplied from an experimental lysimeter soil core leaching study. Results show that basin design influences pollutant accumulation and behaviour in the basins. Management and/or control strategies are discussed for reducing the impact of traffic-related pollutants on the aqueous environment.

  5. The possibilities of municipal operations to control greenhouse gas emissions of road traffic

    Energy Technology Data Exchange (ETDEWEB)

    Saeily, S.

    2004-07-01

    Kyoto protocol obligates industrialized countries to decrease their greenhouse gas emissions averagely by 5,2 percent from the 1990 level before 2008-2012. Finland is committed to stabilize its greenhouse gas emissions to the level of year 1990 before 2008-2012. Carbon monoxide, hydrocarbon, nitric oxide, sulphur dioxide, particles and carbon dioxide are regarded as hazardous emissions of road traffic. These gases are generated by impure burning which is generally expected. From these gases carbon dioxide is considered to be the actual greenhouse gas. Nitric oxide, vaporizing hydrocarbons, sulphur dioxide and carbon monoxide are considered to be indirect greenhouse gases. 20 percent of Finland's carbon dioxide emissions comes from road traffic. Actions aimed to decrease greenhouse gas emissions can be executed at various levels. The smaller the size of an actor is, the more specific the possible actions are. The actions of public administration are based on controlling economy, traffic systems and maintenance of order. The actions of private companies and communities are based on economical profitability. Decisions of individual persons are still the most significant factor in decreasing green house gases generated by passenger traffic. In this study an operations model was developed for municipalities to reduce their greenhouse gas emissions. As a case city of the study was the city of Tampere. Tampere is the third largest city in Finland and has over 15,000 employees. A more specific set of measures was introduced to three different operational units, the University Hospital of Tampere, the primary school of Tammela and the amusement park Saerkaenniemi. For each unit suitable measures were searched by studying the unit's traffic-related significance to help to decrease the unit's greenhouse gas emissions. The traffic generated by municipal operations is mainly related to commuting, work-related, customer and maintenance traffic. Measures which are

  6. Traffic Adaptive Energy Efficient and Low Latency Medium Access Control for Wireless Sensor Networks

    Science.gov (United States)

    Yadav, Rajesh; Varma, Shirshu; Malaviya, N.

    2008-05-01

    Medium access control for wireless sensor networks has been a very active research area in the recent years. The traditional wireless medium access control protocol such as IEEE 802.11 is not suitable for the sensor network application because these are battery powered. The recharging of these sensor nodes is expensive and also not possible. The most of the literature in the medium access for the sensor network focuses on the energy efficiency. The proposed MAC protocol solves the energy inefficiency caused by idle listening, control packet overhead and overhearing taking nodes latency into consideration based on the network traffic. Simulation experiments have been performed to demonstrate the effectiveness of the proposed approach. The validation of the simulation results of the proposed MAC has been done by comparing it with the analytical model. This protocol has been simulated in Network Simulator ns-2.

  7. Evaluation of Early Ground Control Station Configurations for Interacting with a UAS Traffic Management (UTM) System

    Science.gov (United States)

    Dao, Arik-Quang V.; Martin, Lynne; Mohlenbrink, Christoph; Bienert, Nancy; Wolte, Cynthia; Gomez, Ashley; Claudatos, Lauren; Mercer, Joey

    2017-01-01

    The purpose of this paper is to report on a human factors evaluation of ground control station design concepts for interacting with an unmanned traffic management system. The data collected for this paper comes from recent field tests for NASA's Unmanned Traffic Management (UTM) project, and covers the following topics; workload, situation awareness, as well as flight crew communication, coordination, and procedures. The goal of this evaluation was to determine if the various software implementations for interacting with the UTM system can be described and classified into design concepts to provide guidance for the development of future UTM interfaces. We begin with a brief description of NASA's UTM project, followed by a description of the test range configuration related to a second development phase. We identified (post hoc) two classes in which the ground control stations could be grouped. This grouping was based on level of display integration. The analysis was exploratory and informal. It was conducted to compare ground stations across those two classes and against the aforementioned topics. Herein, we discuss the results.

  8. Investigation of postural edema in the lower extremities of traffic control workers

    Directory of Open Access Journals (Sweden)

    Ana Paula Nunes Pereira Brito

    2013-12-01

    Full Text Available OBJECTIVE: Determine the prevalence of postural edema and investigate whether working posture - sitting down or standing up - affect its frequency. METHODS: Sixteen traffic control agents were assessed by water displacement volumetry and the results were analyzed in two groups, depending on working posture. Those who worked standing up for more than 4 hours were allocated to the SU group and those who worked sitting down for more than 4 hours were allocated to the SD group. Each worker was assessed before and after their working shift for three consecutive days. Data were analyzed using ANOVA and the test of equality of two proportions. The significance level was set at p ≤ 0.05. The assessment showed that members of both groups had postural edema of the lower extremities (p ≤ 0.001. RESULTS: When the frequency of postural edema was compared across groups, a trend was observed for greater edema formation in the SU group than in the SD group, although without statistically significant difference. CONCLUSION: It was concluded that traffic control agents suffer postural edema after 4 hours working in either of the postures investigated although with a predominance of edema formation among those who work standing up.

  9. Congestion phenomenon analysis and delayed-feedback control in a modified coupled map traffic flow model containing the velocity difference

    Science.gov (United States)

    Fang, Ya-Ling; Shi, Zhong-Ke; Cao, Jin-Liang

    2015-06-01

    Based on the coupled map car-following model which was presented by Konishi et al. (1999), a modified coupled map car-following model is proposed. Specifically, the velocity difference between two successive vehicles is included in the model. The stability condition is given for the change of the speed of the preceding vehicle on the base of the control theory. We derive a condition under which the traffic jam never occurs in our model. Furthermore, in order to suppress traffic jams, we use static and dynamic version of decentralized delayed-feedback control for each vehicle, respectively, and provide a systematic procedure for designing the controller. In addition, the controller of each vehicle does not include any other vehicle information in real traffic flows.

  10. Selection Guidelines for Central Heat Plant Controls.

    Science.gov (United States)

    1994-11-01

    21 PID Controllers ............................................... 22 Combustion Control...Therefore, closed-loop control is preferred for boiler control. PID Controllers Figure 9 shows the basic functions of a closed loop controller

  11. Performance Evaluation of Adaptive Rate Control (ARC for Burst Traffic over ATM Network

    Directory of Open Access Journals (Sweden)

    V.Ramesh

    2010-01-01

    Full Text Available Many research works have already been done for congestion control and resource management in ATM networks using static and dynamic algorithms. However, no comprehensive scheme has been suggested, which can claim optimized the resource allocations fulfilling the requirements of quality of services (QoS for existing and incoming sources. The paper suggests a new approach, which would make the dynamic allocation of resources by controlling the input rate (l, output/server rate (m and buffer size (c individually or in conjunction. The newly proposed approach with dynamical allocation of resources is much more comprehensive in nature and claims a shorter convergence time than the other previously suggested schemes based on similar dynamic allocation principle. In this paper we describe an Adaptive Rate Control (ARC implemented to improve the performance of high-speed network to handle burst traffic by guaranteeing the cell loss ratio (CLR for all cell streams. First, the cases in which a Tahoe, Reno, New Reno, SACK and Plain schemes are applicable in peak-cell-rate (PCR are discussed. The ARC improves the performance by regulating the increment (up and the decrease (down of window size (flow control. Incoming traffic rate, number of cell drop, preset size of the window and estimated delay time are taken into account for this regulation. Simulations are used to investigate how Tahoe, Reno, New Reno, SACK and Plain can conduct, as congestion existed. Then we compare these results from four schemes to the “Plain” scheme (no flow control application and to the proposed ARC. By altering windows size for the mentioned six schemes, we can obtain the supportive results.

  12. THE DDTCI SWITCH ALGORITHM FOR ABR TRAFFIC CONTROL IN ATM NETWORKS

    Institute of Scientific and Technical Information of China (English)

    Lu Zhaoyi; Ning Yuxin

    2005-01-01

    For the issue of flow control for Available Bit Rate (ABR) traffic in ATM network,a new improved Explicit Rate (ER) algorithm named Dynamic Double Threshold Congestion Indication (DDTCI) algorithm is presented based on the Explicit Forward Congestion Indication (EFCI) Current Cell Rate (CCR) algorithm and Relative Rate (RR) algorithm. Different from the early ER algorithm, both the high-level and the low-level threshold is dynamically changing according to the state of the bottleneck node. We determinate the congestion state with the information of the two dynamic threshold, and control the cell rate of the source by feed back mechanism. Except for the well performance in both link utilization and fairness in distribution of available bandwidth, the improved algorithm can alleviate the fluctuation of sending rate dramatically. The mechanism is modeled by a fluid model, and the useful expressions are derived.Simulation results show up our conclusion.

  13. A Simulation-Based Framework for the Cooperation of VMS Travel Guidance and Traffic Signal Control

    Directory of Open Access Journals (Sweden)

    Meng Li

    2014-01-01

    Full Text Available Nowadays, both travel guidance systems and traffic signal control systems are quite common for urban traffic management. In order to achieve collaborative effect, different models had been proposed in the last two decades. In recent years, with the development of variable message sign (VMS technology, more and more VMS panels are installed on major arterials to provide highly visible and concise graphs or text messages to drivers, especially in developing countries. To discover drivers’ responses to VMS, we establish a drivers’ en route diversion model according to a stated-preference survey. Basically, we proposed a cooperative mechanism and systematic framework of VMS travel guidance and major arterials signal operations. And then a two-stage nested optimization problem is formulated. To solve this optimization problem, a simulation-based optimization method is adopted to optimize the cooperative strategies with TRANSIMS. The proposed method is applied to the real network of Tianjin City comprising of 30 nodes and 46 links. Simulations show that this new method could well improve the network condition by 26.3%. And analysis reveals that GA with nested dynamic programming is an effective technique to solve the optimization problem.

  14. MODELING MULTI-TRAFFIC ADMISSION CONTROL IN OFDMA SYSTEM USING COLORED PETRI NET

    Institute of Scientific and Technical Information of China (English)

    Yao Yuanyuan; Lu Yanhui; Yang Shouyi

    2012-01-01

    Call Admission Control (CAC) is one of the key traffic management mechanisms that must be deployed in order to meet the strict requirements for dependability imposed on the services provided by modern wireless networks.In this paper,we develop an executable top-down hierarchical Colored Petri Net (CPN) model for multi-traffic CAC in Orthogonal Frequency Division Multiple Access (OFDMA) system.By theoretic analysis and CPN simulation,it is demonstrated that the CPN model is isomorphic to Markov Chain (MC) assuming that each data stream follows Poisson distribution and the corresponding arrival time interval is an exponential random variable,and it breaks through MC's explicit limitation,which includes MC's memoryless property and proneness to state space explosion in evaluating CAC process.Moreover,we present four CAC schemes based on CPN model taking into account call-level and packet-level Quality of Service (QoS).The simulation results show that CPN offers significant advantages over MC in modeling CAC strategies and evaluating their performance with less computational complexity in addition to its flexibility and adaptability to different scenarios.

  15. Potential To Increase Productivity And Sustainability In Argentinean Agriculture With Controlled Traffic Farming: A Short Discussion

    Directory of Open Access Journals (Sweden)

    Antille Diogenes L.

    2015-09-01

    Full Text Available Drivers for and potential barriers against adoption of controlled traffic farming (CTF systems in Argentina are reviewed. Traffic compaction is one of the main factors affecting crop productivity within Argentinean agriculture, and has significant although less quantified impacts on the whole-of-farm system. This suggests that the benefits of no-tillage (NT, which represents the dominant form of cropping in Argentina, are not fully realised. Conservative estimates indicate that crop yields could be improved by at least 15% if NT is used in conjunction with CTF. Cost-benefit analyses of available options for compaction management are required. Despite this, and based on reported evidence internationally, a shift toward increased uptake of CTF within Argentinean agriculture is likely to: (1 improve productivity and farm profitability, (2 enhance environmental performance, and (3 maintain competitiveness of the agricultural sector. Appropriate technical advice and support is a key requirement to drive adoption of CTF. Therefore, the adoption process will benefit from collaboration developed with well-established research and extension organisations in Australia and the United Kingdom, and active engagement of machinery manufacturers.

  16. The efficacy of centralized flow rate control in 802.11-based wireless mesh networks

    KAUST Repository

    Jamshaid, K.

    2013-06-13

    Commodity WiFi-based wireless mesh networks (WMNs) can be used to provide last mile Internet access. These networks exhibit extreme unfairness with backlogged traffic sources. Current solutions propose distributed source-rate control algorithms requiring link-layer or transport-layer changes on all mesh nodes. This is often infeasible in large practical deployments. In wireline networks, router-assisted rate control techniques have been proposed for use alongside end-to-end mechanisms. We wish to evaluate the feasibility of establishing similar centralized control via gateways in WMNs. In this paper, we focus on the efficacy of this control rather than the specifics of the controller design mechanism. We answer the question: Given sources that react predictably to congestion notification, can we enforce a desired rate allocation through a single centralized controller? The answer is not obvious because flows experience varying contention levels, and transmissions are scheduled by a node using imperfect local knowledge. We find that common router-assisted flow control schemes used in wired networks fail in WMNs because they assume that (1) links are independent, and (2) router queue buildups are sufficient for detecting congestion. We show that non-work-conserving, rate-based centralized scheduling can effectively enforce rate allocation. It can achieve results comparable to source rate limiting, without requiring any modifications to mesh routers or client devices. 2013 Jamshaid et al.; licensee Springer.

  17. Pilot and Controller Evaluations of Separation Function Allocation in Air Traffic Management

    Science.gov (United States)

    Wing, David; Prevot, Thomas; Morey, Susan; Lewis, Timothy; Martin, Lynne; Johnson, Sally; Cabrall, Christopher; Como, Sean; Homola, Jeffrey; Sheth-Chandra, Manasi; Mercer, Joey

    2013-01-01

    Two human-in-the-loop simulation experiments were conducted in coordinated fashion to investigate the allocation of separation assurance functions between ground and air and between humans and automation. The experiments modeled a mixed-operations concept in which aircraft receiving ground-based separation services shared the airspace with aircraft providing their own separation service (i.e., self-separation). Ground-based separation was provided by air traffic controllers without automation tools, with tools, or by ground-based automation with controllers in a managing role. Airborne self-separation was provided by airline pilots using self-separation automation enabled by airborne surveillance technology. The two experiments, one pilot-focused and the other controller-focused, addressed selected key issues of mixed operations, assuming the starting point of current-day operations and modeling an emergence of NextGen technologies and procedures. In the controller-focused experiment, the impact of mixed operations on controller performance was assessed at four stages of NextGen implementation. In the pilot-focused experiment, the limits to which pilots with automation tools could take full responsibility for separation from ground-controlled aircraft were tested. Results indicate that the presence of self-separating aircraft had little impact on the controllers' ability to provide separation services for ground-controlled aircraft. Overall performance was best in the most automated environment in which all aircraft were data communications equipped, ground-based separation was highly automated, and self-separating aircraft had access to trajectory intent information for all aircraft. In this environment, safe, efficient, and highly acceptable operations could be achieved for twice today's peak airspace throughput. In less automated environments, reduced trajectory intent exchange and manual air traffic control limited the safely achievable airspace throughput and

  18. Optimal Control and Coordination of Connected and Automated Vehicles at Urban Traffic Intersections

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yue J. [Boston University; Malikopoulos, Andreas [ORNL; Cassandras, Christos G. [Boston University

    2016-01-01

    We address the problem of coordinating online a continuous flow of connected and automated vehicles (CAVs) crossing two adjacent intersections in an urban area. We present a decentralized optimal control framework whose solution yields for each vehicle the optimal acceleration/deceleration at any time in the sense of minimizing fuel consumption. The solu- tion, when it exists, allows the vehicles to cross the intersections without the use of traffic lights, without creating congestion on the connecting road, and under the hard safety constraint of collision avoidance. The effectiveness of the proposed solution is validated through simulation considering two intersections located in downtown Boston, and it is shown that coordination of CAVs can reduce significantly both fuel consumption and travel time.

  19. The large Maf factor Traffic Jam controls gonad morphogenesis in Drosophila.

    Science.gov (United States)

    Li, Michelle A; Alls, Jeffrey D; Avancini, Rita M; Koo, Karen; Godt, Dorothea

    2003-11-01

    Interactions between somatic and germline cells are critical for the normal development of egg and sperm. Here we show that the gene traffic jam (tj) produces a soma-specific factor that controls gonad morphogenesis and is required for female and male fertility. tj encodes the only large Maf factor in Drosophila melanogaster, an orthologue of the atypical basic Leu zipper transcription factors c-Maf and MafB/Kreisler in vertebrates. Expression of tj occurs in somatic gonadal cells that are in direct contact with germline cells throughout development. In tj mutant gonads, somatic cells fail to inter-mingle and properly envelop germline cells, causing an early block in germ cell differentiation. In addition, tj mutant somatic cells show an increase in the level of expression for several adhesion molecules. We propose that tj is a critical modulator of the adhesive properties of somatic cells, facilitating germline-soma interactions that are essential for germ cell differentiation.

  20. A Novel Algorithm of Quantum Random Walk in Server Traffic Control and Task Scheduling

    Directory of Open Access Journals (Sweden)

    Dong Yumin

    2014-01-01

    Full Text Available A quantum random walk optimization model and algorithm in network cluster server traffic control and task scheduling is proposed. In order to solve the problem of server load balancing, we research and discuss the distribution theory of energy field in quantum mechanics and apply it to data clustering. We introduce the method of random walk and illuminate what the quantum random walk is. Here, we mainly research the standard model of one-dimensional quantum random walk. For the data clustering problem of high dimensional space, we can decompose one m-dimensional quantum random walk into m one-dimensional quantum random walk. In the end of the paper, we compare the quantum random walk optimization method with GA (genetic algorithm, ACO (ant colony optimization, and SAA (simulated annealing algorithm. In the same time, we prove its validity and rationality by the experiment of analog and simulation.

  1. Iterative Learning Control Approach for Signaling Split in Urban Traffic Networks with Macroscopic Fundamental Diagrams

    Directory of Open Access Journals (Sweden)

    Fei Yan

    2015-01-01

    Full Text Available Recent analysis of field experiments in cities revealed that a macroscopic fundamental diagram (MFD relating network outflow and network vehicle accumulation exists in the urban traffic networks. It has been further confirmed that an MFD is well defined if the network has regular network topology and homogeneous spatial distribution of vehicle accumulation. However, many real urban networks have different levels of heterogeneity in the spatial distribution of vehicle accumulation. In order to improve the mobility in heterogeneously congested networks, we propose an iterative learning control approach for signaling split, which aims at distributing the accumulation in the networks as homogeneously as possible and ensuring the networks have a larger outflow. The asymptotic convergence of the proposed approach is proved by rigorous analysis and the effectiveness is further demonstrated by extensive simulations.

  2. Intraframe compression of radar image sequences for ship traffic control applications

    Science.gov (United States)

    Andreadis, Alessandro; Benelli, Giuliano; Garzelli, Andrea; Susini, S.

    1996-09-01

    In this paper, an intraframe scheme for high compression of X-band radar images for ship traffic control is proposed. We used a proprietary radar simulator which generates maritime scenarios as seen by one or more radar sites. We propose a modified adaptive discrete cosine transform (MADCT) scheme which allows us to classify each 8 by 8 image block by means of a threshold criterion based on ac and dc activity. The strategy of transmission of the DCT coefficients, the recovering process of blocks incorrectly discarded, and the bit-allocation phase have been properly designed to fit with the particular application. Accurate experimental results, in terms of PSNR and compression ratio, prove the superiority of the novel scheme with respect to standard coding techniques.

  3. A Cognitive Game Theoretic Analysis of Conflict Alerts in Air Traffic Control

    Science.gov (United States)

    Erev, Ido; Gopher, Daniel; Remington, Roger

    1999-01-01

    The current research was motivated by the recommendation made by a joint Government/Industry committee to introduce a new traffic control system, referred to as the Free Flight. This system is designed to use recent new technology to facilitate efficient and safe air transportation. We addressed one of the major difficulties that arise in the design of this and similar multi-agent systems: the adaptive (and slippery) nature of human agents. To facilitate a safe and efficient design of this multi-agent system, designers have to rely on assessments of the expected behavior of the different agents under various scenarios. Whereas the behavior of the computerized agents is predictable, the behavior of the human agents (including air traffic controllers and pilots) is not. Experimental and empirical observations suggest that human agents are likely to adjust their behavior to the design of the system. To see the difficulty that the adaptive nature of human agents creates assume that a good approximation of the way operators currently behave is available. Given this information an optimal design can be performed. The problem arises as the human operator will learn to adjust their behavior to the new system. Following this adjustment process the assumptions made by the designer concerning the operators behavior will no longer be accurate and the system might reach a suboptimal state. In extreme situations these potential suboptimal states might involve unnecessary risk. That is, the fact that operators learn in an adaptive fashion does not imply that the system will become safer as they gain experience. At least in the context of Safety dilemmas, experience can lead to a pareto deficient risk taking behavior.

  4. Pilot and Controller Workload and Situation Awareness with Three Traffic Management Concept

    Science.gov (United States)

    Vu, Kim-Phuong L.; Strybel, Thomas Z.; Kraut, Joshua; Bacon, Paige; Minakata, Katsumi; Battiste, Vernol; Johnson, Walter

    2010-01-01

    This paper reports on workload and situation awareness of pilots and controllers participating in a human-in-the-loop simulation using three different distributed air-ground traffic management concepts. Eight experimental pilots started the scenario in an en-route phase of flight and were asked to avoid convective weather while performing spacing and merging tasks along with a continuous descent approach (CDA) into Louisville Standiford Airport (SDF). Two controllers managed the sectors through which the pilots flew, with one managing a sector that included the Top of Descent, and the other managing a sector that included the merge point for arrival into SDF. At 3-minute intervals in the scenario, pilots and controllers were probed on their workload or situation awareness. We employed one of three concepts of operation that distributed separation responsibility across human controllers, pilots, and automation to measure changes in operator situation awareness and workload. We found that when pilots were responsible for separation, they had higher levels of awareness, but not necessarily higher levels of workload. When controllers are responsible and actively engaged, they showed higher workload levels compared to pilots and changes in awareness that were dependent on sector characteristics.

  5. Tunneling Horizontal IEC 61850 Traffic through Audio Video Bridging Streams for Flexible Microgrid Control and Protection

    Directory of Open Access Journals (Sweden)

    Michael Short

    2016-03-01

    Full Text Available In this paper, it is argued that some low-level aspects of the usual IEC 61850 mapping to Ethernet are not well suited to microgrids due to their dynamic nature and geographical distribution as compared to substations. It is proposed that the integration of IEEE time-sensitive networking (TSN concepts (which are currently implemented as audio video bridging (AVB technologies within an IEC 61850 / Manufacturing Message Specification framework provides a flexible and reconfigurable platform capable of overcoming such issues. A prototype test platform and bump-in-the-wire device for tunneling horizontal traffic through AVB are described. Experimental results are presented for sending IEC 61850 GOOSE (generic object oriented substation events and SV (sampled values messages through AVB tunnels. The obtained results verify that IEC 61850 event and sampled data may be reliably transported within the proposed framework with very low latency, even over a congested network. It is argued that since AVB streams can be flexibly configured from one or more central locations, and bandwidth reserved for their data ensuring predictability of delivery, this gives a solution which seems significantly more reliable than a pure MMS-based solution.

  6. Human-factors engineering for smart transport: design support for car drivers and train traffic controllers.

    Science.gov (United States)

    Lenior, Dick; Janssen, Wiel; Neerincx, Mark; Schreibers, Kirsten

    2006-07-01

    The theme Smart Transport can be described as adequate human-system symbiosis to realize effective, efficient and human-friendly transport of goods and information. This paper addresses how to attune automation to human (cognitive) capacities (e.g. to take care of information uncertainty, operator trust and mutual man-machine adaptations). An introduction to smart transport is presented, including examples of best practice for engineering human factors in the vehicle ergonomics and train traffic control domain. The examples are representative of an ongoing trend in automation and they show how the human role changes from controller to supervisor. Section 2 focuses on the car driver and systems that support, or sometimes even take over, critical parts of the driving task. Due to the diversity of driver ability, driving context and dependence between driver and context factors, there is a need for personalised, adaptive and integrated support. Systematic research is needed to establish sound systems. Section 3 focuses on the train dispatcher support systems that predict train movements, detect potential conflicts and show the dispatcher the possibilities available to solve the detected problems. Via thorough analysis of both the process to be controlled and the dispatcher's tasks and cognitive needs, support functions were developed as part of an already very complex supervision and control system. The two examples, although from a different field, both show the need for further development in cognitive modelling as well as for the value of sound ergonomics task analysis in design practice.

  7. Perpetual factors involved in performance of air traffic controllers using a microwave landing system

    Science.gov (United States)

    Gershzohn, G.

    1978-01-01

    The task involved the control of two simulated aircraft targets per trial, in a 37.0 -km radius terminal area, by means of conventional radar vectoring and/or speed control. The goal was to insure that the two targets crossed the Missed Approach Point (MAP) at the runway threshold exactly 60 sec apart. The effects on controller performance of the MLS configuration under wind and no-wind conditions were examined. The data for mean separation time between targets at the MAP and the range about that mean were analyzed by appropriate analyses of variance. Significant effects were found for mean separation times as a result of the configuration of the MLS and for interaction between the configuration and wind conditions. The analysis of variance for range indicated significantly poorer performance under the wind condition. These findings are believed to be a result of certain perceptual factors involved in radar air traffic control (ATC) using the MLS with separation of targets in time.

  8. Determining treatment frequency for controlling weeds on traffic islands using chemical and non-chemical weed control

    DEFF Research Database (Denmark)

    Rask, Anne Merete; Larsen, S.U.; Andreasen, Christian;

    2013-01-01

    Many public authorities rely on the use of non-chemical weed control methods, due to stringent restrictions on herbicide use in urban areas. However, these methods usually require more repeated treatments than chemical weed management, resulting in increased costs of weed management. In order...... to investigate the efficacy of four non-chemical weed control methods and glyphosate treatment, experiments were carried out on traffic islands in the growing seasons 2005 and 2006. Three trial sites were each divided into six treatment areas, which were either treated with glyphosate, flame, steam, hot air....../flame, hot water or left untreated. The treatments were carried out at regular, predetermined intervals throughout the growing season in 2004, whereas in 2005 and 2006 how many treatments that were required to keep weed cover below a predetermined acceptance level of 2% were investigated. Percentage weed...

  9. A Service Oriented Architecture to Integrate Short Message Service (SMS Notification in Road Traffic Volume Control System

    Directory of Open Access Journals (Sweden)

    Zahi Abu Sarhan

    2013-02-01

    Full Text Available The traffic volume becomes one of the top problems in the world, the volume of traffic spends many time and much money, the traffic volume grows daily, and there is not effective and suitable solutions for grows problem. This paper will present and describe an effective approach to integrate the Service Oriented Architecture with mobile devices and services agents in Traffic Management Systems (TMS. The Traffic Volume Control System (TVCS should enable mobile short message service (SMS notifications. Unfortunately, cellular SMS notification based on services that are not aspect of the TVCS.Developing altered exterior systems and services, to be virtually aspect of TVCS, are one of the most incorporation difficulties. In this paper, a Service Oriented Architecture (SOA approach to includecellular SMS alerts in TVCS is presented. Suggested Structure includes two layers: Service layer and Interface layer. The Service layer includes all the system software. The service layer consists of three sub layers: Orchestration, Application Services, and Agents sub-layers. While the Interface layer interrelates with speed detectors and users via sites, and with exterior organization services via Web services.

  10. Dynamic problem selection in air traffic control training : A comparison between performance, mental effort and mental efficiency

    NARCIS (Netherlands)

    Camp, Gino; Paas, Fred; Rikers, Remy; van Merrienboer, Jeroen

    2001-01-01

    The differential effects on training and training outcome of four methods of problem selection were investigated in a computer-based training for air traffic control. In one method, training problems were given to the participants in a fixed predetermined sequence, from simple to complex. In the oth

  11. [Development of New Mathematical Methodology in Air Traffic Control for the Analysis of Hybrid Systems

    Science.gov (United States)

    Hermann, Robert

    1997-01-01

    The aim of this research is to develop new mathematical methodology for the analysis of hybrid systems of the type involved in Air Traffic Control (ATC) problems. Two directions of investigation were initiated. The first used the methodology of nonlinear generalized functions, whose mathematical foundations were initiated by Colombeau and developed further by Oberguggenberger; it has been extended to apply to ordinary differential. Systems of the type encountered in control in joint work with the PI and M. Oberguggenberger. This involved a 'mixture' of 'continuous' and 'discrete' methodology. ATC clearly involves mixtures of two sorts of mathematical problems: (1) The 'continuous' dynamics of a standard control type described by ordinary differential equations (ODE) of the form: {dx/dt = f(x, u)} and (2) the discrete lattice dynamics involved of cellular automata. Most of the CA literature involves a discretization of a partial differential equation system of the type encountered in physics problems (e.g. fluid and gas problems). Both of these directions requires much thinking and new development of mathematical fundamentals before they may be utilized in the ATC work. Rather than consider CA as 'discretization' of PDE systems, I believe that the ATC applications will require a completely different and new mathematical methodology, a sort of discrete analogue of jet bundles and/or the sheaf-theoretic techniques to topologists. Here too, I have begun work on virtually 'virgin' mathematical ground (at least from an 'applied' point of view) which will require considerable preliminary work.

  12. Investigating the Complexity of Transitioning Separation Assurance Tools into NextGen Air Traffic Control

    Science.gov (United States)

    Gomez, Ashley Nicole; Martin, Lynne Hazel; Homola, Jeffrey; Morey, Susan; Cabrall, Christopher; Mercer, Joey; Prevot, Thomas

    2013-01-01

    In a study, that introduced ground-based separation assurance automation through a series of envisioned transitional phases of concept maturity, it was found that subjective responses to scales of workload, situation awareness, and acceptability in a post run questionnaire revealed as-predicted results for three of the four study conditions but not for the third, Moderate condition. The trend continued for losses of separation (LOS) where the number of LOS events were far greater than expected in the Moderate condition. To offer an account of why the Moderate condition was perceived to be more difficult to manage than predicted, researchers examined the increase in amount and complexity of traffic, increase in communication load, and increased complexities as a result of the simulation's mix of aircraft equipage. Further analysis compared the tools presented through the phases, finding that controllers took advantage of the informational properties of the tools presented but shied away from using their decision support capabilities. Taking into account similar findings from other studies, it is suggested that the Moderate condition represented the first step into a "shared control" environment, which requires the controller to use the automation as a decision making partner rather than just a provider of information. Viewed in this light, the combination of tools offered in the Moderate condition was reviewed and some tradeoffs that may offset the identified complexities were suggested.

  13. p53 as the main traffic controller of the cell signaling network.

    Science.gov (United States)

    Sebastian, Sinto; Azzariti, Amalia; Silvestris, Nicola; Porcelli, Letizia; Russo, Antonio; Paradiso, Angelo

    2010-06-01

    Among different pathological conditions that affect human beings, cancer has received a great deal of attention primarily because it leads to significant morbidity and mortality. This is essentially due to increasing world-wide incidence of this disease and the inability to discover the cause and molecular mechanisms by which normal human cells acquire the characteristics that define cancer cells. Since the discovery of p53 over a quarter of a century ago, it is now recognized that virtually all cell fate pathways of live cells and the decision to die are under the control of p53. Such extensive involvement indicates that p53 protein is acting as a major traffic controller in the cell signaling network. In cancer cells, many cell signaling pathways of normal human cells are rerouted towards immortalization and this is accomplished by the corruption of the main controllers of cell signaling pathways such as p53. This review highlights how p53 signaling activity is altered in cancer cells so that cells acquire the hallmarks of cancer including deregulated infinite self replicative potential.

  14. Roles of the orexin system in central motor control.

    Science.gov (United States)

    Hu, Bo; Yang, Nian; Qiao, Qi-Cheng; Hu, Zhi-An; Zhang, Jun

    2015-02-01

    The neuropeptides orexin-A and orexin-B are produced by one group of neurons located in the lateral hypothalamic/perifornical area. However, the orexins are widely released in entire brain including various central motor control structures. Especially, the loss of orexins has been demonstrated to associate with several motor deficits. Here, we first summarize the present knowledge that describes the anatomical and morphological connections between the orexin system and various central motor control structures. In the next section, the direct influence of orexins on related central motor control structures is reviewed at molecular, cellular, circuitry, and motor activity levels. After the summarization, the characteristic and functional relevance of the orexin system's direct influence on central motor control function are demonstrated and discussed. We also propose a hypothesis as to how the orexin system orchestrates central motor control in a homeostatic regulation manner. Besides, the importance of the orexin system's phasic modulation on related central motor control structures is highlighted in this regulation manner. Finally, a scheme combining the homeostatic regulation of orexin system on central motor control and its effects on other brain functions is presented to discuss the role of orexin system beyond the pure motor activity level, but at the complex behavioral level.

  15. Performance Analysis of Prioritized Call Admission Control Schemes for Integrated Traffic in Wireless Network

    Directory of Open Access Journals (Sweden)

    Madhu Jain

    2013-01-01

    Full Text Available Wireless/mobile communication systems are becoming increasingly popular in recent years. As the wireless resources are scarce, it is important to allocate resources efficiently and carefully, in order to achieve maximum output. The call admission control schemes play a significant role in providing the desired quality of service (QoS by judiciously assigning the radio channels that are available in a micro cell. In this paper, we present two call admission control (CAC schemes for wireless mobile network, (i Prioritized call admission control (PCAC scheme (S1 and (ii Prioritized call admission control scheme with releasing function (S2. Both schemes support integrated traffic i.e. data and voice for both new and handoff attempts. Guard channel concept is used to give the priority to the handoff attempts. To admit more handoff attempts in the cellular system, buffering process is used for the handoff attempts. The concept of balking and reneging is also incorporated for both the schemes. The calls arrive in poisson fashion whereas channel holding time and cell residence times are exponentially distributed. The arrival rate of handoff attempts is computed by using iterative algorithm. Various performance metrics such as blocking probability of new call, blocking probability of handoff data/voice attempts, time out probability of handoff data/voice attempts, force termination probability of handoff data/voice attempts, waiting time of handoff data/voice attempts, carried load, etc. are determined. The sensitivity analysis has also been carried out to facilitate the insights of controllable parameters for real time systems

  16. Allocation of Functions in a Far-Term Air Traffic Control Environment

    Science.gov (United States)

    Homola, Jeffrey; Martin, Lynne; Mercer, Joey; Cabrall, Christopher; Prevot, Thomas

    2011-01-01

    A human-in-the-loop exploration of a ground-based automated separation assurance concept was conducted that involved the allocation of certain functions between humans and automation. This exploration included operations that were sustained for prolonged periods of time with high levels of traffic in the presence of convective weather and scheduling constraints. An investigation into the acceptability of the defined roles and performance of tasks was conducted where it was found that the participants rated the concept and allocation of functions with a high level of acceptability. However, issues were encountered with the automation related to the detection of and response to tactical conflicts. Lower ratings were given on account of these concerns, and it was found that a key contributor to the underlying problems was transitioning aircraft and the uncertainty of their trajectories. Stemming from those results, participants responded that they would rather have direct control over aircraft transitions as well as more control over the tactical conflict resolution automation. In contrast, participants responded that they would rather have the automation place aircraft back on trajectory, and perform weather avoidance and scheduling tasks.

  17. Development of a Framework for the Evaluation of the Environmental Benefits of Controlled Traffic Farming

    Directory of Open Access Journals (Sweden)

    Abdul Mounem Mouazen

    2015-07-01

    Full Text Available Although controlled traffic farming (CTF is an environmentally friendly soil management system, no quantitative evaluation of environmental benefits is available. This paper aims at establishing a framework for quantitative evaluation of the environmental benefits of CTF, considering a list of environmental benefits, namely, reducing soil compaction, runoff/erosion, energy requirement and greenhouse gas emission (GHG, conserving organic matter, enhancing soil biodiversity and fertiliser use efficiency. Based on a comprehensive literature review and the European Commission Soil Framework Directive, the choice of and the weighting of the impact of each of the environmental benefits were made. The framework was validated using data from three selected farms. For Colworth farm (Unilever, UK, the framework predicted the largest overall environmental benefit of 59.3% of the theoretically maximum achievable benefits (100%, as compared to the other two farms in Scotland (52% and Australia (47.3%. This overall benefit could be broken down into: reducing soil compaction (24%, tillage energy requirement (10% and GHG emissions (3%, enhancing soil biodiversity (7% and erosion control (6%, conserving organic matter (6%, and improving fertiliser use efficiency (3%. Similar evaluation can be performed for any farm worldwide, providing that data on soil properties, topography, machinery, and weather are available.

  18. Improving traffic flow at a 2-to-1 lane reduction with wirelessly connected, adaptive cruise control vehicles

    CERN Document Server

    Davis, L C

    2015-01-01

    Wirelessly connected vehicles that exchange information about traffic conditions can reduce delays caused by congestion. At a 2-to-1 lane reduction, the improvement in flow past a bottleneck due to traffic with a random mixture of 40% connected vehicles is found to be 52%. Control is based on connected-vehicle-reported velocities near the bottleneck. In response to indications of congestion the connected vehicles, which are also adaptive cruise control vehicles, reduce their speed in slowdown regions. Early lane changes of manually driven vehicles from the terminated lane to the continuous lane are induced by the slowing connected vehicles. Self-organized congestion at the bottleneck is thus delayed or eliminated, depending upon the incoming flow magnitude. For the large majority of vehicles, travel times past the bottleneck are substantially reduced. Control is responsible for delaying the onset of congestion as the incoming flow increases. Adaptive cruise control increases the flow out of the congested stat...

  19. An application-layer based centralized information access control for VPN

    Institute of Scientific and Technical Information of China (English)

    OUYANG Kai; ZHOU Jing-li; XIA Tao; YU Sheng-sheng

    2006-01-01

    With the rapid development of Virtual Private Network (VPN), many companies and organizations use VPN to implement their private communication. Traditionally, VPN uses security protocols to protect the confidentiality of data, the message integrity and the endpoint authentication. One core technique of VPN is tunneling, by which clients can access the internal servers traversing VPN. However, the tunneling technique also introduces a concealed security hole. It is possible that ifone vicious user can establish tunneling by the VPN server, he can compromise the internal servers behind the VPN server. So this paper presents a novel Application-layer based Centralized Information Access Control (ACIAC) for VPN to solve this problem.To implement an efficient, flexible and multi-decision access control model, we present two key techniques to ACIAC-the centralized management mechanism and the stream-based access control. Firstly, we implement the information center and the constraints/events center for ACIAC. By the two centers, we can provide an abstract access control mechanism, and the material access control can be decided dynamically by the ACIAC's constraint/event mechanism. Then we logically classify the VPN communication traffic into the access stream and the data stream so that we can tightly couple the features of VPN communication with the access control model. We also provide the design of our ACIAC prototype in this paper.

  20. Centralized Stochastic Optimal Control of Complex Systems

    Energy Technology Data Exchange (ETDEWEB)

    Malikopoulos, Andreas [ORNL

    2015-01-01

    In this paper we address the problem of online optimization of the supervisory power management control in parallel hybrid electric vehicles (HEVs). We model HEV operation as a controlled Markov chain using the long-run expected average cost per unit time criterion, and we show that the control policy yielding the Pareto optimal solution minimizes the average cost criterion online. The effectiveness of the proposed solution is validated through simulation and compared to the solution derived with dynamic programming using the average cost criterion.

  1. Lagrangian Multi-Class Traffic State Estimation

    OpenAIRE

    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 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...

  2. Human factors issues in the use of artificial intelligence in air traffic control. October 1990 Workshop

    Science.gov (United States)

    Hockaday, Stephen; Kuhlenschmidt, Sharon (Editor)

    1991-01-01

    The objective of the workshop was to explore the role of human factors in facilitating the introduction of artificial intelligence (AI) to advanced air traffic control (ATC) automation concepts. AI is an umbrella term which is continually expanding to cover a variety of techniques where machines are performing actions taken based upon dynamic, external stimuli. AI methods can be implemented using more traditional programming languages such as LISP or PROLOG, or they can be implemented using state-of-the-art techniques such as object-oriented programming, neural nets (hardware or software), and knowledge based expert systems. As this technology advances and as increasingly powerful computing platforms become available, the use of AI to enhance ATC systems can be realized. Substantial efforts along these lines are already being undertaken at the FAA Technical Center, NASA Ames Research Center, academic institutions, industry, and elsewhere. Although it is clear that the technology is ripe for bringing computer automation to ATC systems, the proper scope and role of automation are not at all apparent. The major concern is how to combine human controllers with computer technology. A wide spectrum of options exists, ranging from using automation only to provide extra tools to augment decision making by human controllers to turning over moment-by-moment control to automated systems and using humans as supervisors and system managers. Across this spectrum, it is now obvious that the difficulties that occur when tying human and automated systems together must be resolved so that automation can be introduced safely and effectively. The focus of the workshop was to further explore the role of injecting AI into ATC systems and to identify the human factors that need to be considered for successful application of the technology to present and future ATC systems.

  3. A Data-Driven Control Design Approach for Freeway Traffic Ramp Metering with Virtual Reference Feedback Tuning

    Directory of Open Access Journals (Sweden)

    Shangtai Jin

    2014-01-01

    Full Text Available ALINEA is a simple, efficient, and easily implemented ramp metering strategy. Virtual reference feedback tuning (VRFT is most suitable for many practical systems since it is a “one-shot” data-driven control design methodology. This paper presents an application of VRFT to a ramp metering problem of freeway traffic system. When there is not enough prior knowledge of the controlled system to select a proper parameter of ALINEA, the VRFT approach is used to optimize the ALINEA's parameter by only using a batch of input and output data collected from the freeway traffic system. The extensive simulations are built on both the macroscopic MATLAB platform and the microscopic PARAMICS platform to show the effectiveness and applicability of the proposed data-driven controller tuning approach.

  4. Effects of shift work in air traffic controllers: a systematic review based on the Prisma method

    Directory of Open Access Journals (Sweden)

    Alisson Vieira Marcolino

    2015-07-01

    Full Text Available Air Traffic Controllers (ATC perform very complex functions of great responsibility. Due to the necessities of the job, they are submitted to a work shift system which makes their schedule irregular. The alternation of work shifts can result in effects that cause damages to their work performance and quality of life. Objective: To explore the effects of shift work in ATCs through a systematic review based on the Preferred Reporting Items for Systematic Reviews and Meta-Analysis model (PRISMA. Methodological procedures: The systematic review was conducted based on three databases: PubMed, Science Direct and Web of Science. Results: A total of 748 articles were found, 487 from PubMed, 240 from Science Direct and 21 from Web of Science; seven articles were included in the review after the application of eligibility criteria. Conclusions: The researches showed effects that affect mainly the night shifts, caused by alteration in sleep quality, somnolence and fatigue, resulting in decreased performance and increasing the risk of air accidents.

  5. Effect of adaptive cruise control systems on mixed traffic flow near an on-ramp

    CERN Document Server

    Davis, L C

    2005-01-01

    Mixed traffic flow consisting of vehicles equipped with adaptive cruise control (ACC) and manually driven vehicles is analyzed using car-following simulations. Unlike simulations that show suppression of jams due to increased string stability, simulations of merging from an on-ramp onto a freeway have not thus far demonstrated a substantial positive impact of ACC. In this paper cooperative merging is proposed to increase throughput and increase distance traveled in a fixed time (reduce travel times). In such a system an ACC vehicle senses not only the preceding vehicle in the same lane but also the vehicle immediately in front in the opposite lane. Prior to reaching the merge region, the ACC vehicle adjusts its velocity to ensure that a safe gap for merging is obtained. If on-ramp demand is moderate, partial implementation of cooperative merging where only main line ACC vehicles react to an on-ramp vehicle is effective. Significant improvement in throughput (18%) and increases up to 3 km in distance traveled ...

  6. Data link air traffic control and flight deck environments: Experiment in flight crew performance

    Science.gov (United States)

    Lozito, Sandy; Mcgann, Alison; Corker, Kevin

    1993-01-01

    This report describes an experiment undertaken in a full mission simulation environment to investigate the performance impact of, and human/system response to, data-linked Air Traffic Control (ATC) and automated flight deck operations. Subjects were twenty pilots (ten crews) from a major United States air carrier. Crews flew the Advanced Concepts Flight Simulator (ACFS), a generic 'glass cockpit' simulator at NASA Ames. The method of data link used was similar to the data link implementation plans for a next-generation aircraft, and included the capability to review ATC messages and directly enter ATC clearance information into the aircraft systems. Each crew flew experimental scenarios, in which data reflecting communication timing, errors and clarifications, and procedures were collected. Results for errors and clarifications revealed an interaction between communication modality (voice v. data link) and communication type (air/ground v. intracrew). Results also revealed that voice crews initiated ATC contact significantly more than data link crews. It was also found that data link crews performed significantly more extraneous activities during the communication task than voice crews. Descriptive data from the use of the review menu indicate the pilot-not-flying accessing the review menu most often, and also suggest diffulty in accessing the target message within the review menu structure. The overall impact of communication modality upon air/ground communication and crew procedures is discussed.

  7. Effect of adaptive cruise control systems on mixed traffic flow near an on-ramp

    Science.gov (United States)

    Davis, L. C.

    2007-06-01

    Mixed traffic flow consisting of vehicles equipped with adaptive cruise control (ACC) and manually driven vehicles is analyzed using car-following simulations. Simulations of merging from an on-ramp onto a freeway reported in the literature have not thus far demonstrated a substantial positive impact of ACC. In this paper cooperative merging for ACC vehicles is proposed to improve throughput and increase distance traveled in a fixed time. In such a system an ACC vehicle senses not only the preceding vehicle in the same lane but also the vehicle immediately in front in the other lane. Prior to reaching the merge region, the ACC vehicle adjusts its velocity to ensure that a safe gap for merging is obtained. If on-ramp demand is moderate, cooperative merging produces significant improvement in throughput (20%) and increases up to 3.6 km in distance traveled in 600 s for 50% ACC mixed flow relative to the flow of all-manual vehicles. For large demand, it is shown that autonomous merging with cooperation in the flow of all ACC vehicles leads to throughput limited only by the downstream capacity, which is determined by speed limit and headway time.

  8. UAS Air Traffic Controller Acceptability Study. 2; Evaluating Detect and Avoid Technology and Communication Delays in Simulation

    Science.gov (United States)

    Comstock, James R., Jr.; Ghatas, Rania W.; Consiglio, Maria C.; Chamberlain, James P.; Hoffler, Keith D.

    2015-01-01

    This study evaluated the effects of communications delays and winds on air traffic controller ratings of acceptability of horizontal miss distances (HMDs) for encounters between Unmanned Aircraft Systems (UAS) and manned aircraft in a simulation of the Dallas-Ft. Worth (DFW) airspace. Fourteen encounters per hour were staged in the presence of moderate background traffic. Seven recently retired controllers with experience at DFW served as subjects. Guidance provided to the UAS pilots for maintaining a given HMD was provided by information from Detect and Avoid (DAA) self-separation algorithms (Stratway+) displayed on the Multi-Aircraft Control System. This guidance consisted of amber "bands" on the heading scale of the UAS navigation display indicating headings that would result in a loss of well clear between the UAS and nearby traffic. Winds tested were successfully handled by the DAA algorithms and did not affect the controller acceptability ratings of the HMDs. Voice communications delays for the UAS were also tested and included one-way delay times of 0, 400, 1200, and 1800 msec. For longer communications delays, there were changes in strategy and communications flow that were observed and reported by the controllers. The aim of this work is to provide useful information for guiding future rules and regulations applicable to flying UAS in the NAS. Information from this study will also be of value to the Radio Technical Commission for Aeronautics (RTCA) Special Committee 228 - Minimum Performance Standards for UAS.

  9. Costs of traffic injuries

    DEFF Research Database (Denmark)

    Kruse, Marie

    2015-01-01

    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......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...

  10. Complaints of Poor Sleep and Risk of Traffic Accidents: A Population-Based Case-Control Study.

    Directory of Open Access Journals (Sweden)

    Pierre Philip

    Full Text Available This study aimed to determine the sleepiness-related factors associated with road traffic accidents.A population based case-control study was conducted in 2 French agglomerations. 272 road accident cases hospitalized in emergency units and 272 control drivers matched by time of day and randomly stopped by police forces were included in the study. Odds ratios were calculated for the risk of road traffic accidents.As expected, the main predictive factor for road traffic accidents was having a sleep episode at the wheel just before the accident (OR 9.97, CI 95%: 1.57-63.50, p<0.05. The increased risk of traffic accidents was 3.35 times higher in subjects who reported very poor quality sleep during the last 3 months (CI 95%: 1.30-8.63, p<0.05, 1.69 times higher in subjects reporting sleeping 6 hours or fewer per night during the last 3 months (CI 95%: 1.00-2.85, p<0.05, 2.02 times higher in subjects reporting symptoms of anxiety or nervousness in the previous day (CI 95%: 1.03-3.97, p<0.05, and 3.29 times higher in subjects reporting taking more than 2 medications in the last 24 h (CI 95%: 1.14-9.44, p<0.05. Chronic daytime sleepiness measured by the Epworth Sleepiness Scale, expressed heavy snoring and nocturnal leg movements did not explain traffic accidents.Physicians should be attentive to complaints of poor sleep quality and quantity, symptoms of anxiety-nervousness and/or drug consumption in regular car drivers.

  11. Feeding patterns and performance of cows in controlled cow traffic in automatic milking systems.

    Science.gov (United States)

    Melin, M; Svennersten-Sjaunja, K; Wiktorsson, H

    2005-11-01

    Two groups of dairy cows monitored from 3 to 19 wk postpartum were subjected to 2 different cow traffic routines in an automatic milking system with control gates and an open waiting area. Using different time settings in the control gates, the groups of cows were separated by average milking frequency; cows in the high milking frequency routine had a minimum of 4 h between milkings (MF(4)) and were milked 3.2 +/- 0.1 times daily, whereas cows in the low milking frequency routine had at least 8 h between milkings (MF8) and were milked 2.1 +/- 0.1 times daily. Cows in the 2 groups were switched to the opposite milking frequency control for wk 18 and 19. The increased milking frequency resulted in a higher milk yield of about 9% through 16 wk of early lactation Although the higher milk yield was not significant when measured as energy-corrected milk, significant interactions of milking frequency and study period for milk yield and energy-corrected milk yield were consistent with a yield response when cows were milked more frequently. Meal criteria estimated for each individual cow were used to group feeding visits into meals. During MF4, cows fed in fewer meals per day and had longer meals than during MF8. The control gates were used efficiently, with only a few passages not resulting in actual meals. Although the voluntary meal intervals seemed to be short, the average milking frequency was far below that theoretically possible. This was explained by individual differences in milking frequency and long intervals from when a cow was redirected in a control gate until it arrived in the milking unit. A wide individual range in the voluntary interval between the first and the second meal in the milking cycle suggests that fixed time limits for control gates set on group level have no justifiable biological basis. It was also concluded that primiparous cows were well adapted to the automatic milking system after 2 wk in the barn.

  12. Perspective on traffic control: Aspects of freeway control, intersection control and the control of transit flow in the Netherlands

    NARCIS (Netherlands)

    Hakkesteegt, P.

    1988-01-01

    Paper presented at the 1988 TRB Annual Meeting, Washington D.C., USA. The first part of this paper deals with the control and signalling system for motorways, directed to a more efficient use of available road capacity and to the improvement of road safety. The second part gives some insight into th

  13. Alcohol, psychoactive substances and non-fatal road traffic accidents - a case-control study

    Directory of Open Access Journals (Sweden)

    Bogstrand Stig

    2012-09-01

    Full Text Available Abstract Background The prevalence of alcohol and other psychoactive substances is high in biological specimens from injured drivers, while the prevalence of these psychoactive substances in samples from drivers in normal traffic is low. The aim of this study was to compare the prevalence of alcohol and psychoactive substances in drivers admitted to hospital for treatment of injuries after road traffic accidents with that in drivers in normal traffic, and calculate risk estimates for the substances, and combinations of substances found in both groups. Methods Injured drivers were recruited in the hospital emergency department and drivers in normal conditions were taken from the hospital catchment area in roadside tests of moving traffic. Substances found in blood samples from injured drivers and oral fluid samples from drivers in moving traffic were compared using equivalent cut off concentrations, and risk estimates were calculated using logistic regression analyses. Results In 21.9% of the injured drivers, substances were found: most commonly alcohol (11.5% and stimulants eg. cocaine or amphetamines (9.4%. This compares to 3.2% of drivers in normal traffic where the most commonly found substances were z-hypnotics (0.9% and benzodiazepines (0.8%. The greatest increase in risk of being injured was for alcohol combined with any other substance (OR: 231.9, 95% CI: 33.3- 1615.4, p  Conclusion The prevalence of psychoactive substances was higher among injured drivers than drivers in normal moving traffic. The risk of accident is greatly increased among drivers who tested positive for alcohol, in particular, those who had also ingested one or more psychoactive substances. Various preventive measures should be considered to curb the prevalence of driving under the influence of psychoactive substances as these drivers constitute a significant risk for other road users as well as themselves.

  14. 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

  15. Suitability Screening Test for Marine Corps Air Traffic Controllers Phase 3: Non-cognitive Test Validation and Cognitive Test Prototype

    Science.gov (United States)

    2014-06-01

    Vocational Aptitude Battery (ASVAB), a test battery that assesses cognitive abilities through performance in reading, mathematics, general science...Tennessee 38055-1000  www.nprst.navy.mil NPRST-TR-14-3 June 2014 Suitability Screening Test for Marine Corps Air Traffic Controllers Phase III: Non...cognitive Test Validation and Cognitive Test Prototype Karen M. Walker, PhD Randy Brou, PhD William L. Farmer, PhD Navy Personnel Research

  16. Towards an agent based traffic regulation and recommendation system for the on-road air quality control

    OpenAIRE

    Sadiq, Abderrahmane; El Fazziki, Abdelaziz; Ouarzazi, Jamal; Sadgal, Mohamed

    2016-01-01

    This paper presents an integrated and adaptive problem-solving approach to control the on-road air quality by modeling the road infrastructure, managing traffic based on pollution level and generating recommendations for road users. The aim is to reduce vehicle emissions in the most polluted road segments and optimizing the pollution levels. For this we propose the use of historical and real time pollution records and contextual data to calculate the air quality index on road networks and gen...

  17. Human activity under high pressure: A case study on fluctuation scaling of air traffic controller's communication behaviors

    Science.gov (United States)

    Wang, Yanjun; Zhang, Qiqian; Zhu, Chenping; Hu, Minghua; Duong, Vu

    2016-01-01

    Recent human dynamics research has unmasked astonishing statistical characteristics such as scaling behaviors in human daily activities. However, less is known about the general mechanism that governs the task-specific activities. In particular, whether scaling law exists in human activities under high pressure remains an open question. In air traffic management system, safety is the most important factor to be concerned by air traffic controllers who always work under high pressure, which provides a unique platform to study human activity. Here we extend fluctuation scaling method to study air traffic controller's communication activity by investigating two empirical communication datasets. Taken the number of controlled flights as the size-like parameter, we show that the relationships between the average communication activity and its standard deviation in both datasets can be well described by Taylor's power law, with scaling exponent α ≈ 0.77 ± 0.01 for the real operational data and α ≈ 0.54 ± 0.01 for the real-time training data. The difference between the exponents suggests that human dynamics under pressure is more likely dominated by the exogenous force. Our findings may lead to further understanding of human behavior.

  18. A control method applied to mixed traffic flow for the coupled-map car-following model

    Science.gov (United States)

    Cheng, Rong-Jun; Han, Xiang-Lin; Lo, Siu-Ming; Ge, Hong-Xia

    2014-03-01

    In light of previous work [Phys. Rev. E 60 4000 (1999)], a modified coupled-map car-following model is proposed by considering the headways of two successive vehicles in front of a considered vehicle described by the optimal velocity function. The non-jam conditions are given on the basis of control theory. Through simulation, we find that our model can exhibit a better effect as p = 0.65, which is a parameter in the optimal velocity function. The control scheme, which was proposed by Zhao and Gao, is introduced into the modified model and the feedback gain range is determined. In addition, a modified control method is applied to a mixed traffic system that consists of two types of vehicle. The range of gains is also obtained by theoretical analysis. Comparisons between our method and that of Zhao and Gao are carried out, and the corresponding numerical simulation results demonstrate that the temporal behavior of traffic flow obtained using our method is better than that proposed by Zhao and Gao in mixed traffic systems.

  19. Starnet, a fiber optic metropolitan area network with centralized control

    Science.gov (United States)

    Bacilieri, P.; Caccia, B.; Cardarelli, R.; Carlucci, G. P.; Ciaffoni, O.; Coli, M.; Di Pirro, G.; Ferrer, M. L.; Ghiselli, A.; Martini, A.; Medici, G.; Mirabelli, G.; Pace, E.; Santonico, R.; Trasatti, L.; Valente, E.; Valentini, S.

    1989-12-01

    We present here a project involving a new long distance, high speed, fiber optic network with a passive star topology. The medium access mechanism is based on a centralized controller allowing channel reservation. This controller is connected to each station through an independent pair of optical fibers. It grants access using a deterministic scheme (DAMA/ICCC, demand assignment multiple access by independent centrally controlled channel) by means of a Round Robin algorithm allowing a simple implementation of priority levels and very high data channel efficiency. An overview of the first implementation design is given and some experimental results are presented.

  20. Initial afferent lymphatic vessels controlling outbound leukocyte traffic from skin to lymph nodes.

    Directory of Open Access Journals (Sweden)

    Ignacio eMelero

    2013-12-01

    Full Text Available Tissue drains fluid and macromolecules through lymphatic vessels, which are lined by a specialized endothelium that expresses peculiar differentiation proteins, not found in blood vessels (i.e: LYVE-1, Podoplanin, PROX-1 and VEGFR-3. Lymphatic capillaries are characteristically devoid of a continuous basal membrane and are anchored to the ECM by elastic fibers that act as pulling ropes which open the vessel to avoid oedema if tissue volume increases, as it occurs upon inflammation. Lymphatic vessels are also crucial for the transit of T lymphocytes and antigen presenting cells from tissue to draining lymph nodes. Importantly, cell traffic control across lymphatic endothelium is differently regulated under resting and inflammatory conditions. Under steady-state non-inflammatory conditions, leukocytes enter into the lymphatic capillaries through basal membrane gaps (portals. This entrance is integrin-independent and seems to be mainly guided by CCL21 chemokine gradients acting on leukocytes expressing CCR7. In contrast, inflammatory processes in lymphatic capillaries involve a plethora of cytokines, chemokines, leukocyte integrins and other adhesion molecules. Importantly, under inflammation a role for integrins and their ligands becomes apparent and, as a consequence, the number of leukocytes entering the lymphatic capillaries multiplies several-fold. Enhancing transmigration of dendritic cells en route to lymph nodes is conceivably useful for vaccination and cancer immunotherapy, whereas interference with such key mechanisms may ameliorate autoimmunity or excessive inflammation. Recent findings illustrate how, transient cell-to-cell interactions between lymphatic endothelial cells and leukocytes contribute to shape the subsequent behaviour of leukocytes and condition the lymphatic vessel for subsequent trans-migratory events.

  1. Multi-Robot Path-Planning Problem for a Heavy Traffic Control Application: A Survey

    Directory of Open Access Journals (Sweden)

    Ebtehal Turki Saho Alotaibi

    2016-06-01

    Full Text Available This survey looked at the methods used to solve multi-autonomous vehicle path-planning for an application of heavy traffic control in cities. Formally, the problem consisted of a graph and a set of robots. Each robot has to reach its destination in the minimum time and number of movements, considering the obstacles and other robots’ paths, hence, the problem is NP-hard. The study found that decoupled centralised approaches are the most relevant approaches for an autonomous vehicle path-planning problem for three reasons: (1 a city is a large environment and coupled centralised approaches scale weakly, (2 the overhead of a coupled decentralised approach to achieve the global optimal will affect the time and memory of the other robots, which is not important in a city configuration and (3 the coupled approaches suppose that the number of robots is defined before they start to find the paths and resolve collisions, while in a city, any car can start at any time and hence, each car should work individually and resolve collisions as they arise. In addition, the study reviewed four decoupled centralised techniques to solve the problem: multi-robot path-planning rapidly exploring random tree (MRRRT, push and swap (PAS, push and rotate (PAR and the Bibox algorithm. The experiments showed that MRRRT is the best for exploring any search space and optimizing the solution. On the other hand, PAS, PAR and Bibox are better in terms of providing a complete solution for the problem and resolving collisions in significantly much less time, the analysis, however, shows that a wider class of solvable instances are excluded from PAS and PAR domain. In addition, Bibox solves a smaller class than the class solved by PAS and PAR in less time, in the worst case, and with a shorter path than PAS and PAR.

  2. Optimal control of systems governed by differential equations with applications in air traffic management and systems biology

    Science.gov (United States)

    Raffard, Robin L.

    Differential equations are arguably the most widespread formalism to model dynamical systems in sciences and engineering. In this dissertation, we strive to design a practical methodology which can be used for the optimal control of most systems modeled by differential equations. Namely, the method is applicable to ordinary differential equations (ODEs), partial differential equations (PDEs) and stochastic differential equations (SDEs) driven by deterministic control. The algorithm draws from both optimization and control theory. It solves the Pontryagin Maximum Principle conditions in an iterative fashion via a novel approximate Newton method. We also extend the method to the case in which multiple agents are involved in the optimal control problem. For this purpose, we use dual decomposition techniques which allow us to decentralize the control algorithm and to distribute the computational load among each individual agent. Most of the dissertation is devoted to promoting the applicability of the method to practical problems in air traffic management and systems biology. In air traffic management; we use the technique to optimize a new PDE-based Eulerian model of the airspace; suitable to represent and control air traffic flow at the scale of the US national airspace. We also apply the technique to aircraft coordination problems in the context of formation flight, in which aircraft dynamics are described by ODEs. In systems biology, we use the method to perform fast parameter identification in the analysis of protein networks, which allows us to gain some insights about the biological processes regulating the system. In particular we perform parameter identification for a PDE model of a spatially distributed network of proteins, playing a key role in the planar cell polarity of Drosophila wings. We also study a general representation of intra-cellular genetic networks, described as a stochastic nonlinear regulatory network, in which our control system approach

  3. The impulse influence function for de-centralized control

    Institute of Scientific and Technical Information of China (English)

    ZHONG Wanxie

    2004-01-01

    Impulse influence matrix function is introduced based on that the de-centralized control analysis is analogous to the sub-structural analysis in structural mechanics. The static sub-structural analysis is analogous to the usual de-centralized control, whereas the dynamic sub-structural analysis corresponds to the de-centralized control theory. The reciprocal symmetry for the impulse influence matrix function is proved, and is solved by the precise integration method for time invariant system, giving the results up to computer precision. Based on the impulse influence functions of subsystems, the combination of subsystems can lead to a set of integral equations and be solved numerically. Numerical example demonstrates the effectiveness of the method.

  4. 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.

  5. Central suboptimal H ∞ control design for nonlinear polynomial systems

    Science.gov (United States)

    Basin, Michael V.; Shi, Peng; Calderon-Alvarez, Dario

    2011-05-01

    This article presents the central finite-dimensional H ∞ regulator for nonlinear polynomial systems, which is suboptimal for a given threshold γ with respect to a modified Bolza-Meyer quadratic criterion including the attenuation control term with the opposite sign. In contrast to the previously obtained results, the article reduces the original H ∞ control problem to the corresponding optimal H 2 control problem, using this technique proposed in Doyle et al. [Doyle, J.C., Glover, K., Khargonekar, P.P., and Francis, B.A. (1989), 'State-space Solutions to Standard H 2 and H ∞ Control Problems', IEEE Transactions on Automatic Control, 34, 831-847]. This article yields the central suboptimal H ∞ regulator for nonlinear polynomial systems in a closed finite-dimensional form, based on the optimal H 2 regulator obtained in Basin and Calderon-Alvarez [Basin, M.V., and Calderon-Alvarez, D. (2008b), 'Optimal Controller for Uncertain Stochastic Polynomial Systems', Journal of the Franklin Institute, 345, 293-302]. Numerical simulations are conducted to verify performance of the designed central suboptimal regulator for nonlinear polynomial systems against the central suboptimal H ∞ regulator available for the corresponding linearised system.

  6. Analysis of Traffic Behavior Control Object and Its Characteristics%交通行为控制的对象及其特性分析

    Institute of Scientific and Technical Information of China (English)

    石建军; 李晓莉

    2011-01-01

    本文引入了交通行为控制的概念,明确其控制对象是交通中的人,以同交通系统控制区分开来.首先,借鉴行为科学、管理学和经济学中对人的研究方法,本文提出了以"交通人"的概念来承载交通行为控制对象的共性,明确了"交通人"的内涵与外延及其承载的有关人的性质的假设,并简单阐述了各项假设的意义;其次,通过探讨"交通人"与出行者的区别和联系,明确了"交通人"存在的时空范围;最后详细阐述了"交通人"存在的三个阶段:出行准备、出行中、交通行为回报阶段,提出交通行为意识、交通行为规范和交通行为回报对出行中的交通行为倾向性有重大的影响作用.%In order to differentiate from traffic system control, a concept of traffic behavior control , whose controlling object is person, was introduced in this paper. First,human research method in behavioral science, management and economics were used for reference, and the concept of “traffic man” was proposed to carry the common characteristics of the objects of traffic behavior control, and the “traffic man”possessed connotation , extension, and several assumptions of the human natures and also their implications were raised. Second, the spatial and temporal existence sphere of the “traffic man” was explained through discussion on the assumption distinctions and similarities between the “traffic man” and trip maker. Finally, three stages of the “traffic man” were elaborated: preparations for trip, in trip, traffic behavior return.It suggested that the traffic behavior consciousness, traffic behavior norms and traffic behavior return influenced the tendency of traffic behavior greatly

  7. Increased risk of traffic accidents in subjects with latent toxoplasmosis: a retrospective case-control study

    Directory of Open Access Journals (Sweden)

    Malý Marek

    2002-07-01

    Full Text Available Abstract Background The parasite Toxoplasma gondii infects 30–60% of humans worldwide. Latent toxoplasmosis, i.e., the life-long presence of Toxoplasma cysts in neural and muscular tissues, leads to prolongation of reaction times in infected subjects. It is not known, however, whether the changes observed in the laboratory influence the performance of subjects in real-life situations. Methods The seroprevalence of latent toxoplasmosis in subjects involved in traffic accidents (N = 146 and in the general population living in the same area (N = 446 was compared by a Mantel-Haenszel test for age-stratified data. Correlation between relative risk of traffic accidents and level of anti-Toxoplasma antibody titre was evaluated with the Cochran-Armitage test for trends. Results A higher seroprevalence was found in the traffic accident set than in the general population (Chi2MH = 21.45, p 95= 1.76–4.01 times higher risk of an accident than the toxoplasmosis-negative subjects. The OR significantly increased with level of anti-Toxoplasma antibody titre (p 95 = 1.14–3.03 for the 99 subjects with low antibody titres (8 and 16, higher (OR = 4.78, C.I.95 = 2.39–9.59 for the 37 subjects with moderate titres (32 and 64, and very high (OR = 16.03, C.I.95 = 1.89–135.66 for the 6 subjects with titres higher than 64. Conclusion The subjects with latent toxoplasmosis have significantly increased risk of traffic accidents than the noninfected subjects. Relative risk of traffic accidents decreases with the duration of infection. These results suggest that 'asymptomatic' acquired toxoplasmosis might in fact represent a serious and highly underestimated public health problem, as well as an economic problem.

  8. Study on Control Algorithm of Traffic Signals at Intersections Based on Optimizing Sub-area Traffic Flows%基于子区域交通流优化的交叉口信号控制研究

    Institute of Scientific and Technical Information of China (English)

    臧利林; 朱文兴

    2012-01-01

    In order to reduce average delay time of passing vehicles and improve urban area traffic efficiency, considering actual geographical characteristics of intersections and sub-area traffic data, a control model for traffic signals at intersections was built based on optimizing sub-area traffic flows, and genetic algorithm was used to find out the optimal solution of the model. With traffic signals coordination of neighboring intersections considered, vehicle minimal delay time was chosen as the optimization object in the model. HCM2000 was adopted to calculate vehicle delay time and Robertson model was embedded in the optimization procedure, which ensured the proposed model to be feasible and effective. VC+ 3- 6. 0 software was applied to programm and calculate an optimal control plan for traffic signals at intersections. Finally, simulation by CORSIM was implemented to verifythe validity of the control plan. The results show that the proposed model can obtain better traffic efficiency than the coordination control method based on existing common cycle, and provides a new signal control idea at intersections for urban traffic.%为了减少车辆平均延误时间,提高城市区域交通通行效率,结合实际交叉口地理特征和区域交通流数据,建立了一种基于子区域交通流优化的交叉口信号控制模型,并应用遗传算法获得模型的最优解。在模型中,考虑相邻交叉口信号之间的协调,以车辆平均延误时间最小为优化目标,采用HCM2000延误计算方法,并在优化过程中嵌入Robertson车队离散模型,保证提出模型的可行性和有效性。在VC++6.0中编写程序,获得交叉口信号最优控制方案,最后通过CORSIM仿真证明该控制方案的优劣。结果表明:与现有基于共同周期的协调控制方法相比,所提出的模型能够获得更优的交通效益,为区域交通信号控制提供了一种新的思路。

  9. Admission Control of Integrated Voice and Data CDMA/TDD System Considering Asymmetric Traffic and Power Limit

    Institute of Scientific and Technical Information of China (English)

    CAOYanbo; ZHOUBin; LIChengshu

    2004-01-01

    In this paper, we research an admission control scheme of integrated voice and data CDMA/TDD (Code division multiple access/Time division duplex) system considering asymmetric traffic and power limit. A new user can access the system only if the outage probabilities it experiences on the uplink and downlink time slots are below a threshold value. Based on the power limit the results show the voice and data blocking probabilities under different cell coverage~ arrival rates and various uplink/downlink time slot allocation patterns. Furthermore, multicode and multislot schemes are also evaluated under the presented admission control scheme.

  10. Stochastic modeling of the dynamics of incident-induced lane traffic states for incident-responsive local ramp control

    Science.gov (United States)

    Sheu, Jiuh-Biing

    2007-12-01

    Incident-induced traffic congestion has been recognized as a critical issue to solve in the development of advanced freeway incident management systems. This paper investigates the applicability of a stochastic optimal control approach to real-time incident-responsive local ramp control on freeways. The architecture of the proposed ramp control system embeds two primary functions including (1) real-time estimation of incident-induced lane traffic states and (2) dynamic prediction of ramp-metering rates in response to the changes of incident impacts. To accomplish the above two goals, a discrete-time nonlinear stochastic optimal control model is proposed, followed by the development of a recursive prediction algorithm. Based on the simulation data, the numerical results of model tests indicate that the proposed method permits relieving incident impacts particularly under low-volume and medium-volume conditions, relative to high-volume lane-blocking conditions. Particularly, the incident-induced queue lengths can be improved by 50.1% and 67.9%, compared to the existing ramp control and control-free strategies, respectively.

  11. Vertical Handoff and Admission Control Strategy in 4G Wireless Network Using Centrality Graph Theory

    Directory of Open Access Journals (Sweden)

    A. Ferdinand Christopher

    2014-06-01

    Full Text Available Vertical Handoff (VHO is a crucial mechanism for the architecture of the Fourth Generation (4G Heterogeneous Wireless Networks (HWN, because the users of 4G-HWN are capable of switching to any network in a seamless manner. These algorithms need to be practical and true to a wide range of applications hence utilization of an application layer parameter is important to decide the handoff and admission control. As a noticeable number of OSN users increased among smart phones, this study proposes a deployment of social context incorporated with vertical handoff and admission control algorithms called VHO-AC for the 4G-HWN environment. Admission of a node is decided based on the Graph Centrality Theory, which is contributing their measures to design an application layer parameter called Social Centrality Measure (SCM. The simulation results show that social network traffic flowing out of 2G and 3G base stations is much reduced than the existing SCVH method.

  12. Towards an agent based traffic regulation and recommendation system for the on-road air quality control.

    Science.gov (United States)

    Sadiq, Abderrahmane; El Fazziki, Abdelaziz; Ouarzazi, Jamal; Sadgal, Mohamed

    2016-01-01

    This paper presents an integrated and adaptive problem-solving approach to control the on-road air quality by modeling the road infrastructure, managing traffic based on pollution level and generating recommendations for road users. The aim is to reduce vehicle emissions in the most polluted road segments and optimizing the pollution levels. For this we propose the use of historical and real time pollution records and contextual data to calculate the air quality index on road networks and generate recommendations for reassigning traffic flow in order to improve the on-road air quality. The resulting air quality indexes are used in the system's traffic network generation, which the cartography is represented by a weighted graph. The weights evolve according to the pollution indexes and path properties and the graph is therefore dynamic. Furthermore, the systems use the available pollution data and meteorological records in order to predict the on-road pollutant levels by using an artificial neural network based prediction model. The proposed approach combines the benefits of multi-agent systems, Big data technology, machine learning tools and the available data sources. For the shortest path searching in the road network, we use the Dijkstra algorithm over Hadoop MapReduce framework. The use Hadoop framework in the data retrieve and analysis process has significantly improved the performance of the proposed system. Also, the agent technology allowed proposing a suitable solution in terms of robustness and agility.

  13. Relationship between Air Traffic Selection and Training (AT-SAT)) Battery Test Scores and Composite Scores in the Initial en Route Air Traffic Control Qualification Training Course at the Federal Aviation Administration (FAA) Academy

    Science.gov (United States)

    Kelley, Ronald Scott

    2012-01-01

    Scope and Method of Study: This study focused on the development and use of the AT-SAT test battery and the Initial En Route Qualification training course for the selection, training, and evaluation of air traffic controller candidates. The Pearson product moment correlation coefficient was used to measure the linear relationship between the…

  14. Traffic Network Computer Analysis Method Under trffic Management and Control%一种交通网络的计算机表示方法

    Institute of Scientific and Technical Information of China (English)

    彭培培; 黄卫; 陆建

    2001-01-01

    In this paper,densed chart is used to analyze traffic network anda method is developed to automatically identify the direction of flow in traffic network by compute.Then,traffic management and control can be well handled,for example sole-direction traffic.Consequently, a traffic network computer analysis method under traffic management and control is developed, and it can increase the accuracy of traffic planning.%文章采用密集表方法来表示交通管制措施条件下的交通网络,并且使用一种自动辨识网络中的交通流的流向方法,然后对主要的交通管制措施进行表示,如单向交通等,从而初步形成一种交通管制条件下的网络计算机分析方法,这种分析方法可以提高交通规划的精确性。

  15. CFO finance network centrality, errors and internal control material weaknessess

    NARCIS (Netherlands)

    Schabus, M.

    2015-01-01

    CFOs finance networks matter in determining certain accounting and reporting outcomes. Drawing on social network theory, this study shows that CFO centrality in a network of financial experts is inversely related to the occurrence of restatements due to errors and disclosure of internal control mate

  16. Centralized and decentralized control of structural vibration and sound radiation

    NARCIS (Netherlands)

    Engels, W.P.; Baumann, O.N.; Elliott, S.J.; Fraanje, P.R.

    2006-01-01

    This paper examines the performance of centralized and decentralized feedback controllers on a plate with multiple colocated velocity sensors and force actuators. The performance is measured by the reduction in either kinetic energy or sound radiation, when the plate is excited with a randomly distr

  17. Use of FBG sensors for bridge structural monitoring and traffic control

    Science.gov (United States)

    Caponero, Michele A.; Colonna, Danilo; Gruppi, Marco; Pallotta, Massimo; Salvadori, Robert

    2004-06-01

    This paper describes an application of Fiber Bragg Grating sensors devoted to both health monitoring of road bridge structures and traffic load monitoring. The ultimate aim of the application is the remote continuous monitoring of the structures, with real time acquisition of the dynamic and quasi-static deformations inferred by both the road traffic and the daily and seasonal thermal variations. A Fiber Bragg Grating network composed of 24 sensors has been installed on the bridge on the Po river of the 'A21 Torino Brescia' Italian Highway. The bridge is a concrete structure, and sensors are applied on various rebar components. The sensors were installed directly on the rebars, adopting a special technique specifically developed for permanent concrete embedding. An extensive data acquisition program is in progress with the aim of both health monitoring and in transit lorry weighing. Results are discussed and planned future work is presented.

  18. Coordinated control of a combined cycle thermoelectric central; Control coordinado de una central termoelectrica de ciclo combinado

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Parra, Marino; Castelo Cuevas, Luis [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1998-03-01

    In this paper the coordinated control (CC) of the Distributed Control System (Sistema de Control Distribuido) (SICODI) of the Combined Cycle Central of Gomez Palacio, Durango, is presented. The description of the control scheme and its realization in software is made. From the scheme the operation strategies and automation, supervision and control are described in detail. The software components of the programming are described, the program structure and control data and its implementation in working stations VAX 3100 under the operating system VMS (Virtual Memory System), are described. [Espanol] En este articulo se presenta el control coordinado (CC) del Sistema de Control Distribuido (Sicodi) de la central de ciclo combinado Gomez Palacio, Durango. Se describe el esquema de control y su realizacion en software. Del esquema se detallan las estrategias de operacion y automatizacion, supervision y control. Del software se describen los componentes de la programacion, la estructura de programas y datos del control y su implementacion en estaciones de trabajo VAX 3100 bajo el sistema operativo VMS (Virtual Memory System).

  19. Soil compaction of various Central European forest soils caused by traffic of forestry machines with various chassis

    Directory of Open Access Journals (Sweden)

    Michal Allman

    2015-12-01

    Full Text Available Aim of study: The primary objective of this paper was to compare the effects of different types of forestry machine chassis on the compaction of the top layers of soil and to define the soil moisture content level, at which machine traffic results in maximum compaction.Area of study: Measurements were conducted in eight forest stands located in Slovakia and the Czech Republic. The soil types in the stands subjected to the study were luvisols, stagnosols, cambisols, and rendzinas.Material and Methods: The measurements were focused on tracked and wheeled (equipped with low pressure tyres cut-to-length machines, and skidders equipped with wide and standard tyres. The bulk density of soil was determined from soil samples extracted from the ruts, the centre of the skid trail, and the undisturbed stand. To determine soil moisture content, at which the soil is the most susceptible to compaction, the Proctor standard test was employed.Main results: The moisture content for maximal compaction fluctuated from 12% to 34.06%. Wheeled machines compacted the soil to 1.24 – 1.36 g.cm-3 (30.3 – 35.4 % compaction in dried state. Bulk density of soil in stands where tracked machine operated was lower, ranging from 1.02 to 1.06 g.cm-3 (25.3 % compaction.Research highlights: All wheeled machines caused the same amount of soil compaction in the ruts, despite differences in tyres, machine weight, etc. Maximum compaction caused by forestry machines occurred at minimal moisture contents, easily achievable in European climatic conditions.  Keywords: soil compaction; bulk density; soil moisture content limits; cut-to-length machines; skidders.

  20. Spontaneous centralization of control in a network of company ownerships

    CERN Document Server

    Krause, Sebastian M; Bornholdt, Stefan

    2013-01-01

    We introduce a model for the adaptive evolution of a network of company ownerships. In a recent work it has been shown that the empirical global network of corporate control is marked by a central, tightly connected "core" made of a small number of large companies which control a significant part of the global economy. Here we show how a simple, adaptive "rich get richer" dynamics can account for this characteristic, which incorporates the increased buying power of more influential companies, and in turn results in even higher control. We conclude that this kind of centralized structure can emerge without it being an explicit goal of these companies, or as a result of a well-organized strategy.

  1. Spontaneous centralization of control in a network of company ownerships.

    Directory of Open Access Journals (Sweden)

    Sebastian M Krause

    Full Text Available We introduce a model for the adaptive evolution of a network of company ownerships. In a recent work it has been shown that the empirical global network of corporate control is marked by a central, tightly connected "core" made of a small number of large companies which control a significant part of the global economy. Here we show how a simple, adaptive "rich get richer" dynamics can account for this characteristic, which incorporates the increased buying power of more influential companies, and in turn results in even higher control. We conclude that this kind of centralized structure can emerge without it being an explicit goal of these companies, or as a result of a well-organized strategy.

  2. Interrelation of the Problems of the Aircraft Fleet Development and the Improvement of the Air Traffic Control System

    Directory of Open Access Journals (Sweden)

    Mihail Yurevich Smurov

    2016-07-01

    Full Text Available In the article the problems of air transport have been identified. Among these problems, the congestion of airports and airspace and the need for development and modernization of the airport network are of particular importance. In this regard, the authors consider the improvement of the air traffic control system (ATC system by integrating existing ATC systems into a single global system with the use of unified international standards, rules and procedures. The article also specifies the main indicators characterizing the dynamics of the development of the air transport industry in Russia and abroad.

  3. Hopf bifurcation and uncontrolled stochastic traffic-induced chaos in an RED-AQM congestion control system

    Institute of Scientific and Technical Information of China (English)

    Wang Jun-Song; Yuan Rui-Xi; Gao Zhi-Wei; Wang De-Jin

    2011-01-01

    We study the Hopf bifurcation and the chaos phenomena in a random early detection-based active queue management (RED-AQM) congestion control system with a communication delay. We prove that there is a critical value of the communication delay for the stability of the RED-AQM control system. Furthermore,we show that the system will lose its stability and Hopf bifurcations will occur when the delay exceeds the critical value. When the delay is close to its critical value,we demonstrate that typical chaos patterns may be induced by the uncontrolled stochastic traffic in the RED-AQM control system even if the system is still stable,which reveals a new route to the chaos besides the bifurcation in the network congestion control system. Numerical simulations are given to illustrate the theoretical results.

  4. Hopf bifurcation and uncontrolled stochastic traffic-induced chaos in an RED-AQM congestion control system

    Science.gov (United States)

    Wang, Jun-Song; Yuan, Rui-Xi; Gao, Zhi-Wei; Wang, De-Jin

    2011-09-01

    We study the Hopf bifurcation and the chaos phenomena in a random early detection-based active queue management (RED-AQM) congestion control system with a communication delay. We prove that there is a critical value of the communication delay for the stability of the RED-AQM control system. Furthermore, we show that the system will lose its stability and Hopf bifurcations will occur when the delay exceeds the critical value. When the delay is close to its critical value, we demonstrate that typical chaos patterns may be induced by the uncontrolled stochastic traffic in the RED-AQM control system even if the system is still stable, which reveals a new route to the chaos besides the bifurcation in the network congestion control system. Numerical simulations are given to illustrate the theoretical results.

  5. Centrality in the Global Network of Corporate Control

    CERN Document Server

    Takes, Frank W

    2016-01-01

    Corporations across the world are highly interconnected in a large global network of corporate control. This paper investigates the global board interlock network, covering 400,000 firms linked through 1,700,000 edges representing shared directors between these firms. The main focus is on the concept of centrality, which is used to investigate the embeddedness of firms from a particular country within the global network. The study results in three contributions. First, to the best of our knowledge for the first time we can investigate the topology as well as the concept of centrality in corporate networks at a global scale, allowing for the largest cross-country comparison ever done in interlocking directorates literature. We demonstrate, amongst other things, extremely similar network topologies, yet large differences between countries when it comes to the relation between economic prominence indicators and firm centrality. Second, we introduce two new metrics that are specifically suitable for comparing the...

  6. 基于WSN的路口交通信号控制设计%Intelligent Traffic Control Design Based on Wireless Sensors Network

    Institute of Scientific and Technical Information of China (English)

    任晓莉

    2011-01-01

    为了缓解道路交通拥堵,减少车辆延误,节约交通能源,控制车辆在交叉路口顺畅通行,提出了一种基于无线传感器网的智能交通信号控制设计.利用传感器节点收集的交通信息,结合多agent的协同方法,控制中心进行综合处理,在不同的时段采用不同的路口控制模式,调整各交叉路口的绿信比,协调干线各路口周期的确定和各路口之间的相位差,自适应地控制车辆通行时间.实现了交通信号灯的无线智能控制,从而提高车辆通行效率.实现交通信号控制的智能化、网络化.%In order to reduce traffic jam, decrease vehicle delay, economize traffic energy resources, control the vehicles to pass the crossing smoothly, the intelligent traffic signal control design based on wireless sensors network is proposed. Capturing the traffic information by the sensor nodes, combing the cooperation method of multi-agent, adopting the crossing control modes in the periods of time, the control terminal may control the vehicles' passing time adaptively. So the wireless intelligent control of the traffic signal lamp is realized, by which the vehicles' traffic efficiency is improved, and the intelligent and netting traffic control function is implemented.

  7. Pulse Control Assisted Dynamical Decoupling in a Central Spin Model

    Science.gov (United States)

    Li, Zhao-Yan; Wei, Yong-Bo; Wang, Zhao-Ming; Gu, Yong-Jian; Li, Wen-Dong; Ma, Xiao-Ping

    2017-02-01

    We study pulse control assisted dynamical decoupling through a central spin model in a total Hilbert space. We find that the effective decoupling can be realized by applying a sequence of external pulses. Compared with the bang-bang control which needs infinite strength and infinitesimal short pulses, we show that there is a large parameter space that allows an effective nonperturbative dynamical control. Furthermore, our numerical calculation shows that the reliability can be held for random pulses, such as random pulse time interval or random strength.

  8. Dynamic Resectorization and Coordination Technology: An Evaluation of Air Traffic Control Complexity

    Science.gov (United States)

    Brinton, Christopher R.

    1996-01-01

    The work described in this report is done under contract with the National Aeronautics and Space Administration (NASA) to support the Advanced Air Transportation Technology (AATR) program. The goal of this program is to contribute to and accelerate progress in Advanced Air Transportation Technologies. Wyndemere Incorporated is supporting this goal by studying the complexity of the Air Traffic Specialist's role in maintaining the safety of the Air Transportation system. It is envisioned that the implementation of Free Flight may significantly increase the complexity and difficulty of maintaining this safety. Wyndemere Incorporated is researching potential methods to reduce this complexity. This is the final report for the contract.

  9. Sequential interactions with Sec23 control the direction of vesicle traffic

    OpenAIRE

    LORD, christopher; Bhandari, Deepali; Menon, Shekar; Ghassemian, Majid; Nycz, Deborah; Hay, Jesse; Ghosh, Pradipta; Ferro-Novick, Susan

    2011-01-01

    How the directionality of vesicle traffic is achieved remains an important unanswered question in cell biology. The Sec23p/Sec24p coat complex sorts the fusion machinery (SNAREs) into vesicles as they bud from the endoplasmic reticulum. Vesicle tethering to the Golgi begins when the tethering factor TRAPPI binds to Sec23p. Where the coat is released and how this event relates to membrane fusion is unknown. Here we use a yeast transport assay to demonstrate that an ER-derived vesicle retains i...

  10. Online Optimal Control of Connected Vehicles for Efficient Traffic Flow at Merging Roads

    Energy Technology Data Exchange (ETDEWEB)

    Rios-Torres, Jackeline [ORNL; Malikopoulos, Andreas [ORNL; Pisu, Pierluigi [Clemson University

    2015-01-01

    This paper addresses the problem of coordinating online connected vehicles at merging roads to achieve a smooth traffic flow without stop-and-go driving. We present a framework and a closed-form solution that optimize the acceleration profile of each vehicle in terms of fuel economy while avoiding collision with other vehicles at the merging zone. The proposed solution is validated through simulation and it is shown that coordination of connected vehicles can reduce significantly fuel consumption and travel time at merging roads.

  11. 四川大源商业核心区地下交通联系隧道整体消防安全性评价%On the safety evaluation of the urban traffic link tunnel in the Dayuan central business district, Sichuan

    Institute of Scientific and Technical Information of China (English)

    朱杰; 代君雨; 吴建波; 张志刚; 徐钟铭

    2013-01-01

    The present paper is aimed at introducing the results of our safety evaluation of the urban traffic link tunnel in the Dayuan central business district, Sichuan. As is known, urban traffic link tunnels are a novel type of underground transportation and traffic system, which is used to connect traffic trunks and underground garages. Since such tunnels are narrow and limited in their space, there exists a great potential and unexpected haphazards due to the heavy traffic flow and difficult evacuation both for men and for the vehicles. In this paper, we would like to take the urban traffic link tunnels in Dayuan central business district (CBD) , Sichuan, as our case study. In our research, we have tested different mechanical smoke extraction approaches under the different typical fire conditions, verified the validity of the smoke exhausting systems, tested the thermal dynamic phenomena so as to provide a theoretical basis for designing and running a smoke control system in the relevant projects by using the Fire Dynamics Simulator (FDS) numerical simulation software. And, finally, put forward a systematic fire-prevention safety design, so as make it as a reference to the relevant engineering projects at home and abroad. In addition, our evaluation can also serve as a theoretical and constructive reference to formulating the regulations as to the urban traffic link tunnels as compared with the Fire Dynamics Simulator smoke simulation.%城市地下交通联系隧道是一种新型地下公共交通系统,多与城市交通主干道、地下车库相连接,交通流量大,火灾危险性较高,人员安全疏散相对困难,目前尚无此类专业防火设计规范.以四川大源商业核心区地下交通联系隧道为研究对象,采用FDS数值模拟软件对不同火源位置各典型火灾场景进行模拟,验证其排烟系统的有效性并分析隧道内烟气运动规律;在此基础上运用Building Exodus人员疏散软件模拟环道内人员安全疏

  12. An Efficient Machine Learning Based Classification Scheme for Detecting Distributed Command & Control Traffic of P2P Botnets

    Directory of Open Access Journals (Sweden)

    Pijush Barthakur

    2013-11-01

    Full Text Available Biggest internet security threat is the rise of Botnets having modular and flexible structures. The combined power of thousands of remotely controlled computers increases the speed and severity of attacks. In this paper, we provide a comparative analysis of machine-learning based classification of botnet command & control(C&C traffic for proactive detection of Peer-to-Peer (P2P botnets. We combine some of selected botnet C&C traffic flow features with that of carefully selected botnet behavioral characteristic features for better classification using machine learning algorithms. Our simulation results show that our method is very effective having very good test accuracy and very little training time. We compare the performances of Decision Tree (C4.5, Bayesian Network and Linear Support Vector Machines using performance metrics like accuracy, sensitivity, positive predictive value(PPV and F-Measure. We also provide a comparative analysis of our predictive models using AUC (area under ROC curve. Finally, we propose a rule induction algorithm from original C4.5 algorithm of Quinlan. Our proposed algorithm produces better accuracy than the original decision tree classifier.

  13. Improving traffic flow at a 2-to-1 lane reduction with wirelessly connected, adaptive cruise control vehicles

    Science.gov (United States)

    Davis, L. C.

    2016-06-01

    Wirelessly connected vehicles that exchange information about traffic conditions can reduce delays caused by congestion. At a 2-to-1 lane reduction, the improvement in flow past a bottleneck due to traffic with a random mixture of 40% connected vehicles is found to be 52%. Control is based on connected-vehicle-reported velocities near the bottleneck. In response to indications of congestion the connected vehicles, which are also adaptive cruise control vehicles, reduce their speed in slowdown regions. Early lane changes of manually driven vehicles from the terminated lane to the continuous lane are induced by the slowing connected vehicles. Self-organized congestion at the bottleneck is thus delayed or eliminated, depending upon the incoming flow magnitude. For the large majority of vehicles, travel times past the bottleneck are substantially reduced. Control is responsible for delaying the onset of congestion as the incoming flow increases. Adaptive cruise control increases the flow out of the congested state at the bottleneck. The nature of the congested state, when it occurs, appears to be similar under a variety of conditions. Typically 80-100 vehicles are approximately equally distributed between the lanes in the 500 m region prior to the end of the terminated lane. Without the adaptive cruise control capability, connected vehicles can delay the onset of congestion but do not increase the asymptotic flow past the bottleneck. Calculations are done using the Kerner-Klenov three-phase theory, stochastic discrete-time model for manual vehicles. The dynamics of the connected vehicles is given by a conventional adaptive cruise control algorithm plus commanded deceleration. Because time in the model for manual vehicles is discrete (one-second intervals), it is assumed that the acceleration of any vehicle immediately in front of a connected vehicle is constant during the time interval, thereby preserving the computational simplicity and speed of a discrete-time model.

  14. Development of a Software Based Firewall System for Computer Network Traffic Control

    Directory of Open Access Journals (Sweden)

    Ikhajamgbe OYAKHILOME

    2009-12-01

    Full Text Available The connection of an internal network to an external network such as Internet has made it vulnerable to attacks. One class of network attack is unauthorized penetration into network due to the openness of networks. It is possible for hackers to sum access to an internal network, this pose great danger to the network and network resources. Our objective and major concern of network design was to build a secured network, based on software firewall that ensured the integrity and confidentiality of information on the network. We studied several mechanisms to achieve this; one of such mechanism is the implementation of firewall system as a network defence. Our developed firewall has the ability to determine which network traffic should be allowed in or out of the network. Part of our studied work was also channelled towards a comprehensive study of hardware firewall security system with the aim of developing this software based firewall system. Our software firewall goes a long way in protecting an internal network from external unauthorized traffic penetration. We included an anti virus software which is lacking in most firewalls.

  15. Sequential interactions with Sec23 control the direction of vesicle traffic.

    Science.gov (United States)

    Lord, Christopher; Bhandari, Deepali; Menon, Shekar; Ghassemian, Majid; Nycz, Deborah; Hay, Jesse; Ghosh, Pradipta; Ferro-Novick, Susan

    2011-05-12

    How the directionality of vesicle traffic is achieved remains an important unanswered question in cell biology. The Sec23p/Sec24p coat complex sorts the fusion machinery (SNAREs) into vesicles as they bud from the endoplasmic reticulum (ER). Vesicle tethering to the Golgi begins when the tethering factor TRAPPI binds to Sec23p. Where the coat is released and how this event relates to membrane fusion is unknown. Here we use a yeast transport assay to demonstrate that an ER-derived vesicle retains its coat until it reaches the Golgi. A Golgi-associated kinase, Hrr25p (CK1δ orthologue), then phosphorylates the Sec23p/Sec24p complex. Coat phosphorylation and dephosphorylation are needed for vesicle fusion and budding, respectively. Additionally, we show that Sec23p interacts in a sequential manner with different binding partners, including TRAPPI and Hrr25p, to ensure the directionality of ER-Golgi traffic and prevent the back-fusion of a COPII vesicle with the ER. These events are conserved in mammalian cells.

  16. Transient analysis of traffic generated by bursty sources, and its application to measurement-based admission control

    NARCIS (Netherlands)

    Mandjes, M.R.H.; Uitert, M.J.G. van

    2000-01-01

    The first part of the paper is devoted to a transient analysis of traffic generated by bursty sources. These sources are governed by a modulating process, whose state determines the traffic rate at which the source transmits. The class of modulating processes contains e.g. on/off traffic sources wit

  17. 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.

  18. 空中交通管制员工作负荷研究%On Workload Issue of Air Traffic Controller

    Institute of Scientific and Technical Information of China (English)

    杨新湦

    2005-01-01

    This paper is focusing on workload leading to stress and fatigue,which,so far,have resulted in real or potential accidents,incidents or errors,not been explored but with impact on the controller everyday,studying workload curve on the real situations based on operational units,e.g. Zhengzhou area control center,and doing certain calculations on the number of air traffic controller needed in accordance with the air traffic to be handled. Lastly,some strategies are put forward.

  19. The association between high-risk behavior and central nervous system injuries: analysis of traffic-related fatalities in a large coroner's series.

    Science.gov (United States)

    Pakula, Andrea; Shaker, Adel; Martin, Maureen; Skinner, Ruby

    2013-10-01

    High-risk behaviors leading to traffic fatalities are often a result of severe traumatic brain and spine injuries. The objective of the study was to analyze patterns of behavior in drivers and motorcyclists that are associated with central nervous system (CNS)-related prehospital deaths that may serve as a basis for future prevention initiatives. Our study group comprised 514 fatalities with severe CNS injuries documented at autopsy. The majority (n = 491) was the result of motor vehicle collisions (MVCs). In this group, male drivers predominated and the majority, 80 per cent, wore seatbelts. Toxicology analysis revealed 53 per cent of drivers with a mean concentration of ethanol above the legal limit. Texting while driving comprised 45 per cent of the study group. Less than 5 per cent of the fatalities were the result of road or weather conditions. In the motorcycle group (n = 23), 100 per cent of the victims were unhelmeted. We report a large autopsy series of CNS-related deaths with analysis of behavioral factors associated with the fatalities. Substance abuse and distracted driving are dominant patterns of high-risk behavior in MVCs and not wearing a motorcycle helmet is deadly for victims of motorcycle crashes.

  20. 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.

  1. 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...

  2. Traffic supervisory/control system for Kobe-Awaji- Naruto expressway of Honshu-Shikoku Bridge Authority; Honshu Shikoku Renrakukyo Kodan nonyu no Kobe Awaji Naruto jidoshado kotsu kansei shisetsu seigyo system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    Toshiba delivered the traffic supervisory/control system for Kobe-Awaji-Naruto expressway of Honshu-Shikoku Bridge Authority opened in May 1998. This traffic supervisory system rapidly exactly collects and services the information on the expressway of 89km including Akashi Kaikyo bridge and O-Naruto bridge. The facility control system totally efficiently maintains and controls various facilities for lighting and air circulation of tunnels on the expressway. The previous control system transmitted road information on traffic volume and traffic congestion to offices by using specific lines and terminals, while this system with a monitoring function using intranet can easily service such information by existing PCs. (translated by NEDO)

  3. Traffic supervisory/control system for Kobe-Awaji- Naruto expressway of Honshu-Shikoku Bridge Authority. Honshu Shikoku Renrakukyo Kodan nonyu no Kobe Awaji Naruto jidoshado kotsu kansei shisetsu seigyo system

    Energy Technology Data Exchange (ETDEWEB)

    1999-03-01

    Toshiba delivered the traffic supervisory/control system for Kobe-Awaji-Naruto expressway of Honshu-Shikoku Bridge Authority opened in May 1998. This traffic supervisory system rapidly exactly collects and services the information on the expressway of 89km including Akashi Kaikyo bridge and O-Naruto bridge. The facility control system totally efficiently maintains and controls various facilities for lighting and air circulation of tunnels on the expressway. The previous control system transmitted road information on traffic volume and traffic congestion to offices by using specific lines and terminals, while this system with a monitoring function using intranet can easily service such information by existing PCs. (translated by NEDO)

  4. Adaptive Traffic Route Control in QoS Provisioning for Cognitive Radio Technology with Heterogeneous Wireless Systems

    Science.gov (United States)

    Yamamoto, Toshiaki; Ueda, Tetsuro; Obana, Sadao

    As one of the dynamic spectrum access technologies, “cognitive radio technology,” which aims to improve the spectrum efficiency, has been studied. In cognitive radio networks, each node recognizes radio conditions, and according to them, optimizes its wireless communication routes. Cognitive radio systems integrate the heterogeneous wireless systems not only by switching over them but also aggregating and utilizing them simultaneously. The adaptive control of switchover use and concurrent use of various wireless systems will offer a stable and flexible wireless communication. In this paper, we propose the adaptive traffic route control scheme that provides high quality of service (QoS) for cognitive radio technology, and examine the performance of the proposed scheme through the field trials and computer simulations. The results of field trials show that the adaptive route control according to the radio conditions improves the user IP throughput by more than 20% and reduce the one-way delay to less than 1/6 with the concurrent use of IEEE802.16 and IEEE802.11 wireless media. Moreover, the simulation results assuming hundreds of mobile terminals reveal that the number of users receiving the required QoS of voice over IP (VoIP) service and the total network throughput of FTP users increase by more than twice at the same time with the proposed algorithm. The proposed adaptive traffic route control scheme can enhance the performances of the cognitive radio technologies by providing the appropriate communication routes for various applications to satisfy their required QoS.

  5. On the System Design and Control Scheme of Traffic Lights%浅谈交通灯系统设计与控制方案

    Institute of Scientific and Technical Information of China (English)

    周庆博

    2014-01-01

    This paper introduces a system design and system control program traffic lights, this design is a traffic light control sys-tem based on single chip. The system uses MSC-51 series single-chip AT89S51-centric device designed traffic light controller. The system has a practical, simple operation, extended features and other advantages.%该文引入了交通灯的系统设计和系统控制方案,此方案设计的交通灯控制系统是基于单片机的。本系统采用MSC-51系列单片机AT89S51为中心器件来设计交通灯控制器。本系统具有实用性强、操作简单、扩展功能强等优点。

  6. Prokineticins in central and peripheral control of human reproduction.

    Science.gov (United States)

    Traboulsi, Wael; Brouillet, Sophie; Sergent, Frederic; Boufettal, Houssine; Samouh, Naima; Aboussaouira, Touria; Hoffmann, Pascale; Feige, Jean Jacques; Benharouga, Mohamed; Alfaidy, Nadia

    2015-11-01

    Prokineticin 1 (PROK1) and (PROK2), are two closely related proteins that were identified as the mammalian homologs of their two amphibian homologs, mamba intestinal toxin (MIT-1) and Bv8. PROKs activate two G-protein linked receptors (prokineticin receptor 1 and 2, PROKR1 and PROKR2). Both PROK1 and PROK2 have been found to regulate a stunning array of biological functions. In particular, PROKs stimulate gastrointestinal motility, thus accounting for their family name "prokineticins". PROK1 acts as a potent angiogenic mitogen, thus earning its other name, endocrine gland-derived vascular endothelial factor. In contrast, PROK2 signaling pathway has been shown to be a critical regulator of olfactory bulb morphogenesis and sexual maturation. During the last decade, strong evidences established the key roles of prokineticins in the control of human central and peripheral reproductive processes. PROKs act as main regulators of the physiological functions of the ovary, uterus, placenta, and testis, with marked dysfunctions in various pathological conditions such as recurrent pregnancy loss, and preeclampsia. PROKs have also been associated to the tumor development of some of these organs. In the central system, prokineticins control the migration of GnRH neurons, a key process that controls reproductive functions. Importantly, mutations in PROK2 and PROKR2 are associated to the development of Kallmann syndrome, with direct consequences on the reproductive system. This review describes the finely tuned actions of prokineticins in the control of the central and peripheral reproductive processes. Also, it discusses future research directions for the use of these cytokines as diagnostic markers for several reproductive diseases.

  7. Virtualized Traffic at Metropolitan Scales

    Directory of Open Access Journals (Sweden)

    David eWilkie

    2015-05-01

    Full Text Available Few phenomena are more ubiquitous than traffic, and few are more significant economically, socially, or environmentally. Any virtual reality system, including virtual globes and immersive multi-player worlds that are set in a modern or futuristic setting feature traffic systems. Virtual reality models can also aid in addressing the challenges of real-world traffic systems, the ever-present gridlock and congestion in cities worldwide: traffic engineers and planners can diagnose system instabilities and explore control strategies in virtual worlds reconstructed from available sensor data. To create these systems, road network models need to be created and represented. Traffic needs to be realistically and efficiently simulated. To analyze real-world scenarios, the traffic conditions need to be estimated and reconstructed. To create virtual scenarios, such as simulated cities, traffic needs to be intelligently and efficiently routed.

  8. Urban Traffic Control Under the Environmenr of Vehicle Infrastructure Integration%车路协同环境下城市交通控制研究

    Institute of Scientific and Technical Information of China (English)

    姚佼; 杨晓光

    2013-01-01

    在梳理城市交通控制随交通信息进步发展脉络的基础上,结合车路协同环境下交通信息采集的特点,综述分析单点控制、协调控制的研究现状,进一步总结了车路协同环境下城市交通控制的发展机遇和挑战.指出车路协同环境下交通流演变模型、基于实时车载数据的控制策略评价,以及面向特殊模式的控制策略是车辆协同环境下城市交通控制的突破口和发展方向.%Based on the summary of research context of synchronization development between traffic control and information technology,the urban traffic signal control at isolated intersections and arterial streets under the environment of Ⅶ (Uehicle infrastructure integration) was analysed,taking the characteristic of traffic information collection under Ⅶ into account.Moreover,the challenge and opportunity of traffic control under Ⅶ was also illustrated.It is concluded that the future research on traffic control under Ⅶ should focus on evolved traffic flow model,probe data based MOE (measurement of effectiveness) of signal control strategy in real time and specific modes oriented signal control strategy.

  9. An Open-Source Microscopic Traffic Simulator

    CERN Document Server

    Treiber, Martin; 10.1109/MITS.2010.939208

    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 and stability of traffic flow, and investigating novel ITS technologies such as adaptive cruise control, inter-vehicle and vehicle-infrastructure communication.

  10. Decentralized Markets versus Central Control: A Comparative Study

    CERN Document Server

    Akkermans, H; 10.1613/jair.627

    2011-01-01

    Multi-Agent Systems (MAS) promise to offer solutions to problems where established, older paradigms fall short. In order to validate such claims that are repeatedly made in software agent publications, empirical in-depth studies of advantages and weaknesses of multi-agent solutions versus conventional ones in practical applications are needed. Climate control in large buildings is one application area where multi-agent systems, and market-oriented programming in particular, have been reported to be very successful, although central control solutions are still the standard practice. We have therefore constructed and implemented a variety of market designs for this problem, as well as different standard control engineering solutions. This article gives a detailed analysis and comparison, so as to learn about differences between standard versus agent approaches, and yielding new insights about benefits and limitations of computational markets. An important outcome is that "local information plus market communica...

  11. Pedestrian road traffic injuries in urban Peruvian children and adolescents: case control analyses of personal and environmental risk factors.

    Directory of Open Access Journals (Sweden)

    Joseph Donroe

    Full Text Available BACKGROUND: Child pedestrian road traffic injuries (RTIs are an important cause of death and disability in poorer nations, however RTI prevention strategies in those countries largely draw upon studies conducted in wealthier countries. This research investigated personal and environmental risk factors for child pedestrian RTIs relevant to an urban, developing world setting. METHODS: This is a case control study of personal and environmental risk factors for child pedestrian RTIs in San Juan de Miraflores, Lima, Perú. The analysis of personal risk factors included 100 cases of serious pedestrian RTIs and 200 age and gender matched controls. Demographic, socioeconomic, and injury data were collected. The environmental risk factor study evaluated vehicle and pedestrian movement and infrastructure at the sites in which 40 of the above case RTIs occurred and 80 control sites. FINDINGS: After adjustment, factors associated with increased risk of child pedestrian RTIs included high vehicle volume (OR 7.88, 95%CI 1.97-31.52, absent lane demarcations (OR 6.59, 95% CI 1.65-26.26, high vehicle speed (OR 5.35, 95%CI 1.55-18.54, high street vendor density (OR 1.25, 95%CI 1.01-1.55, and more children living in the home (OR 1.25, 95%CI 1.00-1.56. Protective factors included more hours/day spent in school (OR 0.52, 95%CI 0.33-0.82 and years of family residence in the same home (OR 0.97, 95%CI 0.95-0.99. CONCLUSION: Reducing traffic volumes and speeds, limiting the number of street vendors on a given stretch of road, and improving lane demarcation should be evaluated as components of child pedestrian RTI interventions in poorer countries.

  12. Influence of deficiencies in traffic control devices in crashes on two-lane rural roads.

    Science.gov (United States)

    López, Griselda; de Oña, Juan; Garach, Laura; Baena, Leticia

    2016-11-01

    One of the main objectives of all public administrations is reducing traffic crashes. To this end, Road Safety Inspections (RSI) stand out as a key measure. Signaling roads is one of the foremost tasks of RSI. A road that is improperly or poorly signaled can lead to incorrect placement or maneuvers of vehicles and ambiguous situations that can increase the risk of crashes. This paper analyses the relationship between road crashes in two-lane rural highways and certain deficiencies in signaling. The results show that deficiencies such as "incomplete removal of road works markings" or "no guide sign or in incorrect position" are the ones associated with a higher probability of crashes in two-lane rural highways. In view of these results, governmental agencies should verify that the original conditions of a highway are re-established after any construction work is completed. They should also continuously follow up on the signaling of this type of highway in order to maintain optimal conditions.

  13. Real time traffic models, decision support for traffic management

    OpenAIRE

    Wismans, L.; De Romph, E.; Friso, K.; Zantema, K.

    2014-01-01

    Reliable and accurate short-term traffic state prediction can improve the performance of real-time traffic management systems significantly. Using this short-time prediction based on current measurements delivered by advanced surveillance systems will support decision-making processes on various control strategies and enhance the performance of the overall network. By taking proactive action deploying traffic management measures, congestion may be prevented or its effects limited. An approach...

  14. Highway Traffic Noise Analysis and Control%公路交通噪声分析与防治

    Institute of Scientific and Technical Information of China (English)

    田华

    2012-01-01

      The Jianchang County portion of highway traffic noise monitoring, Points out the harm of traffic noise, Put forward several measures to reduce traffic noise.%  对建昌县部分交通干线的交通噪声进行监测,指出交通噪声的危害,提出降低交通噪声的几种措施

  15. Central chemoreceptors and neural mechanisms of cardiorespiratory control

    Directory of Open Access Journals (Sweden)

    T.S. Moreira

    2011-09-01

    Full Text Available The arterial partial pressure (P CO2 of carbon dioxide is virtually constant because of the close match between the metabolic production of this gas and its excretion via breathing. Blood gas homeostasis does not rely solely on changes in lung ventilation, but also to a considerable extent on circulatory adjustments that regulate the transport of CO2 from its sites of production to the lungs. The neural mechanisms that coordinate circulatory and ventilatory changes to achieve blood gas homeostasis are the subject of this review. Emphasis will be placed on the control of sympathetic outflow by central chemoreceptors. High levels of CO2 exert an excitatory effect on sympathetic outflow that is mediated by specialized chemoreceptors such as the neurons located in the retrotrapezoid region. In addition, high CO2 causes an aversive awareness in conscious animals, activating wake-promoting pathways such as the noradrenergic neurons. These neuronal groups, which may also be directly activated by brain acidification, have projections that contribute to the CO2-induced rise in breathing and sympathetic outflow. However, since the level of activity of the retrotrapezoid nucleus is regulated by converging inputs from wake-promoting systems, behavior-specific inputs from higher centers and by chemical drive, the main focus of the present manuscript is to review the contribution of central chemoreceptors to the control of autonomic and respiratory mechanisms.

  16. Linking network usage patterns to traffic Gaussianity fit

    NARCIS (Netherlands)

    Oliveira Schmidt, de Ricardo; Sadre, Ramin; Melnikov, Nikolay; Schönwälder, Jürgen; Pras, Aiko

    2014-01-01

    Gaussian traffic models are widely used in the domain of network traffic modeling. The central assumption is that traffic aggregates are Gaussian distributed. Due to its importance, the Gaussian character of network traffic has been extensively assessed by researchers in the past years. In 2001, res

  17. En-Route Vehicular Traffic Optimization

    Directory of Open Access Journals (Sweden)

    Saravanan M

    2015-02-01

    Full Text Available The pathways of information are changing, the physical world itself is becoming a type of information system. In what’s called the Internet of Things (IoT, sensors and actuators embedded in physical objects—from roadways to pacemakers—are linked through wired and wireless networks, often using the same Internet Protocol (IP that connects the Internet. When objects can both sense the environment and communicate, they become tools for understanding complexity and responding to it swiftly. The revolutionary part in all this is that these physical information systems are now beginning to be deployed, and some of them even work largely without human intervention. This paper has addressed the traffic congestion problem with the help of Internet of Things. Increase in the number of vehicles in cities caused by the population and development of economy, has stimulated traffic congestion problems. It is becoming more serious day after day in the present scenario of developing countries. The reason for the same could be categorized as mismanagement of vehicular movement, ineffective system for controlling the mobility of vehicles, uneven roads and traffic snarl-up. Unexpected vehicular queuing is a major concern leading to wasting time of passengers and thwarting ambulance to reach the destination in time. In addition to that, traffic congestion makes it difficult to forecast the travel time accurately causing drivers to allocate more time in travel than scheduled previously. To ease these mounting traffic problems a demonstration is made on the Proof of Concept (POC using the smart city data set provided by Telecom Italia of Milan city, to verify that these concepts have the potential for real world application and could be used by the government sectors or private transport organizations to ameliorate the passenger’s comfort on road which are as follows. A central node is developed which sets the speed limit and predicts a normalized speed

  18. A centralized control architecture for harmonic voltage suppression in islanded microgrids

    DEFF Research Database (Denmark)

    Wang, Xiongfei; Blaabjerg, Frede; Chen, Zhe

    2011-01-01

    This paper proposes a centralized control architecture for harmonic voltage suppression in islanded microgrids. The centralized selective harmonic compensator is developed in addition to the autonomous nonlinear load sharing loop in local controllers of inverter-interfaced Distributed Energy Reso...

  19. 交通数据质量宏观评价与控制方法%Macroscopic Evaluation and Control Method of Traffic Data Quality

    Institute of Scientific and Technical Information of China (English)

    牛世峰; 姜桂艳

    2012-01-01

    针对交通数据质量微观评价方法无法评价交通数据整体质量的问题,提出交通数据宏观评价的思想,在对非正常交通数据分类进行研究的基础上,构建了4个交通数据宏观评价指标,并设计了交通数据宏观评价流程,根据各类非正常交通数据的产生原因,设计了交通数据质量宏观控制方法,利用实测数据验证表明,所设计方法可以实现交通数据质量的宏观评价,并能给出合理的交通数据质量控制策略.%In the light of the problem which evaluate the overall quality of traffic data, the idea of macroscopic evaluation of traffic data is proposed. Four macroscopic evaluation indexes of traffic data are constructed based on the classification of non-normal traffic data, and the flow of macroscopic evaluation of traffic data quality is designed. The macroscopic control method of traffic data quality is designed based on cause analysis of non-normal data. The experimental results indicate that the proposed method can carry out the macroscopic evaluate of traffic data quality, and give a reasonable data quality improvement strategy.

  20. A method of variable speed limit control for traffic flow on freeway mainline%高速公路主线可变限速控制方法

    Institute of Scientific and Technical Information of China (English)

    马明辉; 杨庆芳; 梁士栋

    2015-01-01

    The traffic state would become congested at the bottleneck region during peak period, which increase travel time, and decrease efficiency. From time-space traffic characteristics on freeway mainline, macroscopic traffic flow model METANET is modified to describe the traffic flow with VSL control. Furthermore, based on the modified traffic flow models, establish the VSL models at bottleneck region, with the objective of improving traffic efficiency and decreasing travel time. As part of the VSL control algorithm, the proposed VSL control model is implemented at VISSIM simulation platform, the results reveal that the given VSL values according to real time traffic flow conditions can control the vehicles arriving effectively. Therefore, the implement of VSL control can improve traffic efficiency and decrease travel time effectively.%为了解决高流量状态下高速公路主线瓶颈区域交通流运行态势恶劣,导致车辆行程时间增加、道路通行效率降低等问题,从高速公路交通流运行时-空特性角度出发,对宏观交通模型METANET改进,使其能够描述可变限速控制条件下道路交通流运行状态,并以改进模型为基础,提高通行效率和缩短行程时间为目标,构建高速公路主线交通优化控制模型. 实验结果表明:高速公路主线可变限速控制方法能够根据道路交通流量的变化对安全限速值动态设置,实现对危险区车辆到达率的动态控制. 实施高速公路主线可变限速控制方法可有效提高道路通行效率,缩短车辆行程时间.

  1. Fuzzy Multiobjective Traffic Light Signal Optimization

    Directory of Open Access Journals (Sweden)

    N. Shahsavari Pour

    2013-01-01

    Full Text Available 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 fluctuating traffic volumes. In this paper, the fuzzy traffic light controller is used to optimize the control of fluctuating traffic volumes such as oversaturated or unusual load conditions. The problem is solved by genetic algorithm, and a new defuzzification method is introduced. The performance of the new defuzzification method (NDM is compared with the centroid point defuzzification method (CPDM by using ANOVA. Finally, an illustrative example is presented to show the competency of proposed algorithm.

  2. 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.

  3. 行人横过公路交通灯PLC控制系统设计%Design of Traffic Lights PLC Control System for Pedestrians to Cross Road

    Institute of Scientific and Technical Information of China (English)

    汤文利

    2015-01-01

    This paper proposes traffic lights working principle of pedestrian crossing the road, including the hardware structure and detalled control program of PLC system, analyzes the basic idea of program design. It is of significance for practical application of traffic lights.%提出了行人横过公路交通灯动作原理,给出了用PLC实现这一动作的硬件组成及详细的控制程序并分析了程序设计的基本思路,对于交通灯的实际应用有一定指导意义。

  4. 40 CFR 81.155 - Central Maryland Intrastate Air Quality Control Region.

    Science.gov (United States)

    2010-07-01

    ... Air Quality Control Regions § 81.155 Central Maryland Intrastate Air Quality Control Region. The Central Maryland Intrastate Air Quality Control Region consists of the territorial area encompassed by the... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Central Maryland Intrastate...

  5. 40 CFR 81.138 - Central Arkansas Intrastate Air Quality Control Region.

    Science.gov (United States)

    2010-07-01

    ... Air Quality Control Regions § 81.138 Central Arkansas Intrastate Air Quality Control Region. The Central Arkansas Intrastate Air Quality Control Region consists of the territorial area encompassed by the... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Central Arkansas Intrastate...

  6. 40 CFR 81.143 - Central Virginia Intrastate Air Quality Control Region.

    Science.gov (United States)

    2010-07-01

    ... Air Quality Control Regions § 81.143 Central Virginia Intrastate Air Quality Control Region. The Central Virginia Intrastate Air Quality Control Region consists of the territorial area encompassed by the... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Central Virginia Intrastate...

  7. 40 CFR 81.142 - Central Massachusetts Intrastate Air Quality Control Region.

    Science.gov (United States)

    2010-07-01

    ... Air Quality Control Regions § 81.142 Central Massachusetts Intrastate Air Quality Control Region. The Central Massachusetts Intrastate Air Quality Control Region consists of the territorial area encompassed... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Central Massachusetts Intrastate...

  8. 40 CFR 81.95 - Central Florida Intrastate Air Quality Control Region.

    Science.gov (United States)

    2010-07-01

    ... Quality Control Regions § 81.95 Central Florida Intrastate Air Quality Control Region. The Central Florida Intrastate Air Quality Control Region consists of the territorial area encompassed by the boundaries of the... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Central Florida Intrastate Air...

  9. 40 CFR 81.96 - West Central Florida Intrastate Air Quality Control Region.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false West Central Florida Intrastate Air... Air Quality Control Regions § 81.96 West Central Florida Intrastate Air Quality Control Region. The West Central Florida Intrastate Air Quality Control Region consists of the territorial area...

  10. High-resolution wind and temperature observations from aircraft tracked by Mode-S air traffic control radar

    Science.gov (United States)

    de Haan, S.

    2011-05-01

    Wind, temperature, and humidity observations from radiosonde and aircraft are the main sources of upper air information for meteorology. For mesoscale meteorology, the horizontal coverage of radiosondes is too sparse. Aircraft observations through Aircraft Meteorological Data Relay (AMDAR) sample an atmospheric profile in the vicinity of airports. However, not all aircraft are equipped with AMDAR or have the system activated. Observations inferred from an enhanced tracking and ranging (TAR) air traffic control radar can fill this gap. These radars follows all aircraft in the airspace visible to the radar for air traffic management. The TAR radar at Schiphol airport in Netherlands has a range of 270 km. This Mode-S radar contacts each aircraft every 4 s on which the transponder in the aircraft responds with a message that contains information on flight level, direction, and speed. Combined with the ground track of an aircraft, meteorological information on temperature and wind can be inferred from this information. Because all aircraft are required to respond to the TAR radar, the data volume is extremely large, being around 1.5 million observations per day. Note that there are no extra costs for this data link. The quality of these observations is assessed by comparison to numerical weather prediction (NWP) model information, AMDAR observations, and radiosonde observations. A preprocessing step is applied to enhance the quality of wind and temperature observations, albeit with a reduced time frequency of one observation of horizontal wind vector and temperature per aircraft per minute. Nevertheless, the number of observations per day is still very large. In this paper it is shown that temperature observations from Mode-S, even after corrections, are not very good; an RMS which is twice as large as AMDAR is observed when compared to NWP. In contrast to the temperature observations, the quality found for wind after correction and calibration is good; it is comparable

  11. Can Simulator Immersion Change Cognitive Style? Results from a Cross-Sectional Study of Field-Dependence--Independence in Air Traffic Control Students

    Science.gov (United States)

    Van Eck, Richard N.; Fu, Hongxia; Drechsel, Paul V. J.

    2015-01-01

    Air traffic control (ATC) operations are critical to the U.S. aviation infrastructure, making ATC training a critical area of study. Because ATC performance is heavily dependent on visual processing, it is important to understand how to screen for or promote relevant visual processing abilities. While conventional wisdom has maintained that such…

  12. Integrated Evaluation of Air Traffic Controller Workload Based on Matter-Element Analysis

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ming; HAN Song-chen

    2008-01-01

    A model for evaluating the controller workload was presented based on matter-element analysis, particularly from a man-machine-environment system engineering perspective. On the basis of a questionnaire survey, 18 kinds of indexes which influence the controller workload were determined. By establishing the classical field and node field of the controller workload, the correlation function of the controller workload grade was obtained; then the correlation degree and estimated grade of controller workload were given. A case study verifies the feasibility of the proposed evaluation method.

  13. pH in exhaled breath condensate and nasal lavage as a biomarker of air pollution-related inflammation in street traffic-controllers and office-workers

    Directory of Open Access Journals (Sweden)

    Thamires Marques de Lima

    2013-12-01

    Full Text Available OBJECTIVE: To utilize low-cost and simple methods to assess airway and lung inflammation biomarkers related to air pollution. METHODS: A total of 87 male, non-smoking, healthy subjects working as street traffic-controllers or office-workers were examined to determine carbon monoxide in exhaled breath and to measure the pH in nasal lavage fluid and exhaled breath condensate. Air pollution exposure was measured by particulate matter concentration, and data were obtained from fixed monitoring stations (8-h work intervals per day, during the 5 consecutive days prior to the study. RESULTS: Exhaled carbon monoxide was two-fold greater in traffic-controllers than in office-workers. The mean pH values were 8.12 in exhaled breath condensate and 7.99 in nasal lavage fluid in office-workers; these values were lower in traffic-controllers (7.80 and 7.30, respectively. Both groups presented similar cytokines concentrations in both substrates, however, IL-1β and IL-8 were elevated in nasal lavage fluid compared with exhaled breath condensate. The particulate matter concentration was greater at the workplace of traffic-controllers compared with that of office-workers. CONCLUSION: The pH values of nasal lavage fluid and exhaled breath condensate are important, robust, easy to measure and reproducible biomarkers that can be used to monitor occupational exposure to air pollution. Additionally, traffic-controllers are at an increased risk of airway and lung inflammation during their occupational activities compared with office-workers.

  14. Experimental investigation of effects of Washout control on reducing traffic jam%交通流 Washout 缓解控制方案试验分析

    Institute of Scientific and Technical Information of China (English)

    任鹏飞; 薛鹏; 李可

    2015-01-01

    Aiming at issues of traffic jams in circle,Washout out control scheme was proposed based on optimal velocity functions. Dynamic balancing control system model was established after analyzing the characteristics of cyclic traffic flows. Then indoor experi-mental platform was constructed with LEGO robot cars. Traffic flow and density were collected at a given position in 5 minutes. Compa-ring experimental results with real traffic data,the effectiveness of the model was validated. Introducing Washout controller for each ve-hicle,the data showed that the Washout control scheme can release the traffic jams and the control effect is particularly significant in the early stage of congestion.%针对环状交通流拥堵的问题,基于最优速度函数提出了 Washout 缓解控制方案。分析环状交通流的行进特点,建立系统动态平衡控制模型后,再利用乐高 NXT 模型车搭建室内试验平台。设定运行时间为5 min,定点监测车流密度和流量变化。将试验数据与实测交通数据进行对比,验证了模型的有效性。进一步为被控车流引入 Washout 控制器,试验数据显示该方案可有效缓解交通阻塞,在拥堵形成初期的控制效果尤为明显。

  15. Central motor control failure in fibromyalgia: a surface electromyography study

    Directory of Open Access Journals (Sweden)

    Buskila Dan

    2009-07-01

    Full Text Available Abstract Background Fibromyalgia (FM is characterised by diffuse musculoskeletal pain and stiffness at multiple sites, tender points in characteristic locations, and the frequent presence of symptoms such as fatigue. The aim of this study was to assess whether the myoelectrical manifestations of fatigue in patients affected by FM are central or peripheral in origin. Methods Eight female patients aged 55.6 ± 13.6 years (FM group and eight healthy female volunteers aged 50.3 ± 9.3 years (MCG were studied by means of non-invasive surface electromyography (s-EMG involving a linear array of 16 electrodes placed on the skin overlying the biceps brachii muscle, with muscle fatigue being evoked by means of voluntary and involuntary (electrically elicited contractions. Maximal voluntary contractions (MVCs, motor unit action potential conduction velocity distributions (mean ± SD and skewness, and the mean power frequency of the spectrum (MNF were estimated in order to assess whether there were any significant differences between the two groups and contraction types. Results The motor pattern of recruitment during voluntary contractions was altered in the FM patients, who also showed fewer myoelectrical manifestations of fatigue (normalised conduction velocity rate of changes: -0.074 ± 0.052%/s in FM vs -0.196 ± 0.133%/s in MCG; normalised MNF rate of changes: -0.29 ± 0.16%/s in FM vs -0.66 ± 0.34%/s in MCG. Mean conduction velocity distribution and skewnesses values were higher (p Conclusion The apparent paradox of fewer myoelectrical manifestations of fatigue in FM is the electrophysiological expression of muscle remodelling in terms of the prevalence of slow conducting fatigue-resistant type I fibres. As the only between-group differences concerned voluntary contractions, they are probably more related to central motor control failure than muscle membrane alterations, which suggests pathological muscle fibre remodelling related to altered

  16. Rethinking Traffic Management: Design of Optimizable Networks

    Science.gov (United States)

    2008-06-01

    traffic traverses each path in a network. On the Internet today, end hosts run congestion control to adapt sending rates, routers route traffic on...congestion control to adapt sending rates, routers route traffic on shortest paths based on link weights, and operators tune link weights to direct traffic...Chaintreau and Christophe Diot for giving me the opportunity to intern at Thomson Research Labs in Paris. Thanks to all the interns there for v making it

  17. Use of a total traffic count metric to investigate the impact of roadways on asthma severity: a case-control study

    Directory of Open Access Journals (Sweden)

    deVos Annemarie JBM

    2011-06-01

    Full Text Available Abstract Background This study had two principal objectives: (i to investigate the relationship between asthma severity and proximity to major roadways in Perth, Western Australia; (ii to demonstrate a more accurate method of exposure assessment for traffic pollutants using an innovative GIS-based measure that fully integrates all traffic densities around subject residences. Methods We conducted a spatial case-control study, in which 'cases' were defined as individuals aged under 19 years of age with more severe asthma (defined here as two or more emergency department contacts with asthma in a defined 5-year period versus age- and gender-matched 'controls' with less severe asthma (defined here as one emergency department contact for asthma. Traffic exposures were measured using a GIS-based approach to determine the lengths of the roads falling within a buffer area, and then multiplying them by their respective traffic counts. Results We examined the spatial relationship between emergency department contacts for asthma at three different buffer sizes: 50 metres, 100 metres and 150 metres. No effect was noted for the 50 metre buffer (OR = 1.07; 95% CI: 0.91-1.26, but elevated odds ratios were observed with for crude (unadjusted estimates OR = 1.21 (95% CI: 1.00-1.46 for 100 metre buffers and OR = 1.25 (95% CI: 1.02-1.54 for 150 metre buffers. For adjusted risk estimates, only the 150 metre buffer yielded a statistically significant finding (OR = 1.24; 95% CI:1.00-1.52. Conclusions Our study revealed a significant 24% increase in the risk of experiencing multiple emergency department contacts for asthma for every log-unit of traffic exposure. This study provides support for the hypothesis that traffic related air pollution increases the frequency of health service contacts for asthma. This study used advanced GIS techniques to establish traffic-weighted buffer zones around the geocoded residential location of subjects to provide an accurate

  18. Development and investigation of a pollution control pit for treatment of stormwater from metal roofs and traffic areas.

    Science.gov (United States)

    Dierkes, C; Göbel, P; Lohmann, M; Coldewey, W G

    2006-01-01

    Source control by on-site retention and infiltration of stormwater is a sustainable and proven alternative to classical drainage methods. Unfortunately, sedimentary particles and pollutants from drained surfaces cause clogging and endanger soil and groundwater during long-term operation of infiltration devices. German water authorities recommend the use of infiltration devices, such as swales or swale-trench-systems. Direct infiltration by underground facilities, such as pipes, trenches or sinks, without pretreatment of runoff is generally not permitted. Problems occur with runoff from metal roofs, traffic areas and industrial sites. However, due to site limitations, underground systems are often the only feasible option. To overcome this situation, a pollution control pit was developed with a hydrodynamic separator and a multistage filter made of coated porous concrete. The system treats runoff at source and protects soil, groundwater and receiving waterways. Typically, more than 90% of the pollutants such as sedimentary particles, hydrocarbons and heavy metals can be removed. Filters have been developed to treat even higher polluted stormwater loads from metal roofs and industrial sites. The treatment process is based on sedimentation, filtration, adsorption and chemical precipitation. Sediments are trapped in a special chamber within the pit and can be removed easily. Other pollutants are captured in the concrete filter upstream of the sediment separator chamber. Filters can be easily replaced.

  19. Impacts of Pedestrians on Capacity and Delay of Major Street Through Traffic at Two-Way Stop-Controlled Intersections

    Directory of Open Access Journals (Sweden)

    Zhao Yang

    2015-01-01

    Full Text Available This paper aims to estimate the impacts of pedestrians on capacity and average control delay for the major street through traffic at two-way stop-controlled (TWSC intersections. A procedure was proposed to estimate the expected delay for major street through vehicles based on the pedestrian arrival time and motorist yielding behavior. Field data were collected to calibrate the crucial parameters in the established models. The proposed models were then validated against field measured data. It was found that the calibrated models provided reasonable delay estimates. Based on the established models, sensitivity analyses were conducted to identify the effects of pedestrian arrival rate and motorist yield rate on the capacity of the major street through lanes at TWSC intersections. The results suggested that the capacity of the through movement would decrease with an increase in the pedestrian arrival rate. It was also found that, with the same pedestrian arrival rate, the capacity would decrease as the motorist yield rate became higher, and the magnitude of the capacity reduction would increase with an increase in the pedestrian arrival rate.

  20. The FAA Plans and Programs for the Future Airport and Air Traffic control System.

    Science.gov (United States)

    1980-11-13

    have been effectively resolved through minor software design changes, contrary to self-serving charges by the controllers’ union, the number of...improvements can be achieved. You will hear more later on about the computer and display replacement program. (VU-GRAPH -- ETABS ) o Other work in advanced...tabular weather uata t,’ the controllers, the Electronic Tabular Display Subsystem ( ETABS ) and the Terminal Information Display System (TIDS) will be used

  1. Simulation Model of Traffic Jam at Crossroads

    Directory of Open Access Journals (Sweden)

    Mladen Kalajžić

    2002-11-01

    Full Text Available Traffic congestion is one of the major problems in most cities.It is the consequence of unavoidable motorization, butalso, in many cases, of improper solutions considering constructionof roads or organisation of traffic.This paper deals with one problematic crossroad in thetown of Zadar in which traffic jams occur due to poor organisationof traffic. Using mathematical simulation, the first partproves that traffic jams will certainly occur, and in the secondpart, crossroads signalling is considered as a possible solutionwhich, if combined with intelligent control could significantlyimprove the organisation of traffic at this crossroads.

  2. Two-layer hierarchical control solutions for traffic signal%面向交通信号的两层递阶控制解决方案

    Institute of Scientific and Technical Information of China (English)

    戈军; 周莲英

    2015-01-01

    针对现有交通信号控制系统的诸多不足,提出了一种用于交通信号控制的两层递阶多Agent系统解决方案。通过将交通网络进行区域划分,利用底层Agent控制各交叉口,顶层Agent控制区域,从而实现两层递阶控制。底层Agent采用经典Q学习同步学习最优策略,顶层Agent利用Tile Coding非凡的连续空间处理能力,实现Q学习的动作值函数逼近方法。仿真实验结果表明,该分层递阶控制不但提高了交通信号控制系统效率,而且也为大规模应用提供了很好的可伸缩解决方案。%In view of the existing deficiencies of traffic signal control system, this paper proposes two-layer hierarchical multi-Agent system solution for traffic signal control. Through regional division of the traffic network, it uses the bottom level Agent to control the intersection, the top level Agent to control areas, so as to achieve the two-layer hierarchical con-trol. The bottom level Agent uses the classical Q-learning to synchronize the optimal strategy, the top level Agent utilizes the special continuous space processing ability of Tile Coding to achieve Q learning of action value function approxima-tion method. The simulation test results show that, the hierarchical control not only improves the efficiency of traffic signal control system, but also provides a good scalable solution for large-scale applications.

  3. 40 CFR 81.104 - Central Pennsylvania Intrastate Air Quality Control Region.

    Science.gov (United States)

    2010-07-01

    ... Quality Control Region. 81.104 Section 81.104 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Air Quality Control Regions § 81.104 Central Pennsylvania Intrastate Air Quality Control Region. The Central Pennsylvania Intrastate Air Quality Control Region consists of the territorial area encompassed...

  4. 40 CFR 81.47 - Central Oklahoma Intrastate Air Quality Control Region.

    Science.gov (United States)

    2010-07-01

    ... Quality Control Region. 81.47 Section 81.47 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Air Quality Control Regions § 81.47 Central Oklahoma Intrastate Air Quality Control Region. The Metropolitan Oklahoma Intrastate Air Quality Control Region has been renamed the Central Oklahoma...

  5. A generic approach to generating optimal controlled prespective route guidance in realistic traffic networks

    NARCIS (Netherlands)

    Chen, Y.; Zuurbier, F.S.; Zuylen, H.J. van; Hoogendoorn, S.P.

    2006-01-01

    This paper presents a generic methodology to generate optimal controlled dynamic prescriptive route guidance to be disseminated by means of variable message signs (VMS). The methodology is generic in the sense it can be used on any network topology and network model, with any number of VMS’s, for di

  6. Impact of future time-based operations on situation awareness of air traffic controllers

    NARCIS (Netherlands)

    Oprins, E.A.P.B.; Zwaaf, D.; Eriksson, F.; Merwe, K. van de; Roe, R.

    2009-01-01

    A time-based operation, as planned in the ATM future, is assumed to affect the controllers’ Situation Awareness (SA) due to a higher priority of meeting a time objective and increasing automation. This paper provides SA requirements on the design of controller support tools in time-based operations,

  7. Automatic feedback on cognitive load and emotional state of traffic controllers

    NARCIS (Netherlands)

    Neerincx, M.A.; Harbers, M.; Lim, D.; Tas, V. van der

    2014-01-01

    Workload research in command, information and process-control centers, resulted in a modular and formal Cognitive Load and Emotional State (CLES) model with transparent and easy-to-modify classification and assessment techniques. The model distinguishes three representation and analysis layers with

  8. 基于模糊PID控制的网络异常流量监控设计%Network Abnormal Traffic Monitoring Based on Fuzzy PID Control

    Institute of Scientific and Technical Information of China (English)

    王俊士

    2016-01-01

    In the large network system, because of the network congestion or the virus invasion to produce abnormal network traffic, network traffic monitoring system design and security network security and stability. BP neural network control algorithm is used in the traditional network anomaly traffic monitoring system. The BP neural network's structure is simple, and it is difficult to detect the abnormal traffic. Based on the improved fuzzy PID control system, the traffic flow model and time series analysis model is built. The quantitative recursive entropy feature is extracted. The PID neural network control method is used to design the traffic monitoring system. The simulation results show that this method can detect the abnormal spectrum characteristics accurately, and can be used to detect the abnormal traffic in time domain.%在大型网络系统中,会因为网络拥堵或者病毒入侵产生网络异常流量,通过对网络异常流量的监控系统设计保障网络的安全稳定。传统的网络异常流量监控系统采用BP神经网络控制算法,由于BP神经网络的结构单一性,对异常流量中干扰性较强的数据难以有效检测发现,提出一种基于改进的模糊PID控制的网络流量异常监控系统设计方法,在流量传输模型和时间序列分析模型构建的基础上,提取异常流量序列的定量递归熵特征,采用模糊PID神经网络控制方法进行流量监控系统设计,把监控到的异常流量通过链路信道回馈给输出层。仿真结果表明,采用该方法进行网络异常流量监控,能准确检测出异常的频谱特征,从而在时域上进行追溯定位,实现流量异常点的准确检测,对异常流量的准确检测概率比传统方法高。

  9. Systemic Approach to Traffic Evaluation of Mostar Airport

    Directory of Open Access Journals (Sweden)

    Eldo Raguž

    2005-11-01

    Full Text Available The attempt of this work is to systematically find solutionsfor Mostar Airport development through technical and technologicalharmonization of traffic processes undertaken in twoseparate organizations - airport and air traffic control and coordinationbetween other traffic branches. The work uses theindicators of traffic flows and tourist trends in the region, andtogether with the mentioned simulations it attempts to evaluatethe traffic potentials in the region by affecting the change in thecurrent negative traffic flows at Mostar Airport.

  10. An Optimal Flow Control Algorithm for Real-time Traffic over the Internet

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    According to the Wide Area Network model and queue dynamics in the router, the authors formulate the Internet flow control as a constrained convex programming problem, where the objective is to maximize the total utility and minimize transmission delay and delay jitter of all sources over their transmission rates. Based on this formulation, flow control can be solved by means of a gradient projection algorithm with properly rate iterations. The main difficulty facing the realization of the iteration algorithm is the distributed computation of the congestion measure. Fortunately, Explicit Congestion Notification (ECN) is likely to be used to improving the performance of TCP in the near future. By using ECN, it is possible to realize the iteration algorithm in IP networks. The algorithm is divided into two parts, algorithms in the router and the source. The main advantage of the scheme is its fast convergence ability and robustness, but small queue length fluctuation is unavoidable when the number of users increases.

  11. A Novel Architecture for Adaptive Traffic Control in Network on Chip using Code Division Multiple Access Technique

    Directory of Open Access Journals (Sweden)

    Fatemeh. Dehghani

    2016-08-01

    Full Text Available Network on chip has emerged as a long-term and effective method in Multiprocessor System-on-Chip communications in order to overcome the bottleneck in bus based communication architectures. Efficiency and performance of network on chip is so dependent on the architecture and structure of the network. In this paper a new structure and architecture for adaptive traffic control in network on chip using Code Division Multiple Access technique is presented. To solve the problem of synchronous access to bus based interconnection the code division multiple access technique was applied. In the presented structure that is based upon mesh topology and simple routing method we attempted to increase the exchanged data bandwidth rate among different cores. Also an attempt has been made to increase the performance by isolating the target address transfer path from data transfer path. The main goal of this paper is presenting a new structure to improve energy consumption, area and maximum frequency in network on chip systems using information coding and decoding techniques. The presented structure is simulated using Xilinx ISE software and the results show effectiveness of this architecture.

  12. Application of Agent Technique in Traffic Control%Agent技术在交通控制中的应用

    Institute of Scientific and Technical Information of China (English)

    孙静

    2011-01-01

    The Agent originates the artificial intelligence,the artificial intelligence technique combines distributing type calculation techniques together in the middle of 80's in 20 centuries,appearing the distributing type artificial intelligence.At the same time,the Agent is mentioned more and more,the Agent technical research direction and applications contain more extensive development space,this text mainly introduced the Agent concept,characteristic,type,with many techniques of Agent in application of traffic control system.%Agent技术来源于分布式人工智能DAI领域。也有人将其翻译为智能主体或智能体,Agent技术在90年代成为热门话题,Agent一词越来越多地被提到,Agent技术的研究方向和应用就有了更加广泛的发展空间。主要介绍了Agent的概念、特性、类型,与多Agent技术在交通控制系统中的应用这两大方面的内容。

  13. Assessing Prior Experience in the Selection of Air Traffic Control Specialists

    Science.gov (United States)

    2013-04-01

    Crosstabulation --------------------------B1 APPENDIX C: IFR Operations Experience • Academy Training Performance Crosstabulation ---------C1 APPENDIX...Control Specialist (ATCS) rating? (n=9,333) BQ35 – Do you have prior Instrument Flight Rules ( IFR ) operations experience? (n = 9,349) 2. Hold or...not have a prior ATCS rating. Do you have prior IFR (Instrument Flight Rules) Operations experience? Of the 9,349 respondents to this question

  14. UAS in the NAS Air Traffic Controller Acceptability Study-1: The Effects of Horizontal Miss Distances on Simulated UAS and Manned Aircraft Encounters

    Science.gov (United States)

    Ghatas, Rania W.; Comstock, James R., Jr.; Consiglio, Maria C.; Chamberlain, James P.; Hoffler, Keith D.

    2015-01-01

    This study examined air traffic controller acceptability ratings based on the effects of differing horizontal miss distances (HMDs) for encounters between UAS and manned aircraft. In a simulation of the Dallas/Fort Worth (DFW) East-side airspace, the CAS-1 experiment at NASA Langley Research Center enlisted fourteen recently retired DFW air traffic controllers to rate well-clear volumes based on differing HMDs that ranged from 0.5 NM to 3.0 NM. The controllers were tasked with rating these HMDs from "too small" to "too excessive" on a defined, 1-5, scale and whether these distances caused any disruptions to the controller and/or to the surrounding traffic flow. Results of the study indicated a clear favoring towards a particular HMD range. Controller workload was also measured. Data from this experiment and subsequent experiments will play a crucial role in the FAA's establishment of rules, regulations, and procedures to safely and efficiently integrate UAS into the NAS.

  15. Models for Predictive Railway Traffic Management

    NARCIS (Netherlands)

    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

  16. Comprehensive Craniospinal Radiation for Controlling Central Nervous System Leukemia

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Gary V.; Shihadeh, Ferial [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Kantarjian, Hagop [Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Allen, Pamela [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Rondon, Gabriela; Kebriaei, Partow [Department of Stem Cell Transplantation, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); O' Brien, Susan [Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Kedir, Aziza; Said, Mustefa; Grant, Jonathan D. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Thomas, Deborah A. [Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Gidley, Paul W. [Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Arzu, Isidora; Pinnix, Chelsea; Reed, Valerie [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Dabaja, Bouthaina S., E-mail: bdabaja@mdanderson.org [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States)

    2014-12-01

    Purpose: To determine the benefit of radiation therapy (RT) in resolution of neurologic symptoms and deficits and whether the type of RT fields influences central nervous system (CNS) control in adults with CNS leukemia. Methods and Materials: A total of 163 adults from 1996 to 2012 were retrospectively analyzed. Potential associations between use of radiation and outcome were investigated by univariate and multivariate analysis. Results: The median survival time was 3.8 months after RT. Common presenting symptoms were headache in 79 patients (49%), cranial nerve VII deficit in 46 (28%), and cranial nerve II deficit in 44 (27%). RT was delivered to the base of skull in 48 patients (29%), to the whole brain (WB) in 67 (41%), and to the craniospinal axis (CS) in 48 (29%). Among 149 patients with a total of 233 deficits, resolution was observed in 34 deficits (15%), improvement in 126 deficits (54%), stability in 34 deficits (15%), and progression in 39 deficits (17%). The 12-month CNS progression-free survival was 77% among those receiving CS/WB and 51% among those receiving base of skull RT (P=.02). On multivariate analysis, patients who did not undergo stem cell transplantation after RT and base of skull RT were associated with worse CNS progression-free survival. Conclusions: Improvement or resolution of symptoms occurred in two thirds of deficits after RT. Comprehensive radiation to the WB or CS seems to offer a better outcome, especially in isolated CNS involvement.

  17. Central Systolic Hypertension in Patients with Well-Controlled Hypertension

    Science.gov (United States)

    Potočárová, Mária; Murín, Ján; Kozlíková, Katarína; Luha, Ján; Čaprnda, Martin

    2017-01-01

    Background. Central systolic blood pressure (CSBP) has prognostic significance and simplified devices for its estimation have been introduced recently. The aim of this study was to assess the achievement of the target CSBP in treated hypertensive patients. Subjects and Methods. One hundred patients with well-controlled hypertension were analysed. For CSBP estimation, we used the Arteriograph (TensioMed Ltd.), which uses one cuff for all measurements, the “single-point measurement” approach. Results. We found that 62% of patients had CSBP ≥ 130 mmHg, the suggested cut-off value for hypertension. When sex-specific classification was employed (CSBP ≥ 137 mmHg for female and CSBP ≥ 133 mmHg for male), only 13% of patients (mainly women) remained in the hypertensive range. We also found that 55% of patients had a CSBP higher than brachial pressure. Multiple analyses showed that CSBP was significantly associated with sex, height, and return time. Conclusions. A high proportion of treated hypertensive patients had CSBP levels that exceeded their brachial BP. CSBP positively correlated with lower height and shorter return time of the reflected pressure wave and was significantly higher in females compared to males. These findings suggest that, for CSBP classification, it is important to take height and sex-specific differences into account. PMID:28127560

  18. Orexin, Stress and Central Cardiovascular Control. A Link with Hypertension?

    Science.gov (United States)

    Carrive, Pascal

    2017-03-01

    Orexin, the arousal peptide, originates from neurons located in an area of the dorsal hypothalamus well known for integrating defense responses and their cardiovascular component. Orexin neurons, which are driven in large part by the limbic forebrain, send projections to many regions in the brain, including regions involved in cardiovascular control, as far down as sympathetic preganglionic neurons in the spinal cord. Central injections of orexin evoke sympathetically mediated cardiovascular responses. Conversely, blockade of orexin receptors reduce the cardiovascular responses to acute stressors, preferentially of a psychological nature. More importantly, lasting upregulation of orexin signaling can lead to a hypertensive state. This can be observed in rats exposed to chronic stress as well as in strains known to display spontaneous hypertension such as the spontaneously hypertensive rat (SHR) or the hypertensive BPH/2J Schlager mouse. Thus, there is a link between orexin, stress and hypertension, and orexin upregulation could be a factor in the development of essential hypertension. Orexin receptor antagonists have anti-hypertensive effects that could be of clinical use.

  19. Highway traffic model-based density estimation

    OpenAIRE

    Morarescu, Irinel - Constantin; CANUDAS DE WIT, Carlos

    2011-01-01

    International audience; The travel time spent in traffic networks is one of the main concerns of the societies in developed countries. A major requirement for providing traffic control and services is the continuous prediction, for several minutes into the future. This paper focuses on an important ingredient necessary for the traffic forecasting which is the real-time traffic state estimation using only a limited amount of data. Simulation results illustrate the performances of the proposed ...

  20. Road traffic injuries in Mozambique.

    Science.gov (United States)

    Romão, Francelina; Nizamo, Hanifa; Mapasse, Domingos; Rafico, Momede Mussá; José, João; Mataruca, Simão; Efron, M Lúcia; Omondi, Lucas O; Leifert, Thelma; Bicho, Joaquim M L Marungo

    2003-01-01

    Road traffic injuries affect the economy, health and quality of life of the people of Mozambique. Current road safety programmes are inadequate and inefficient given the magnitude of the problem. Data reported on road traffic crashes in the period 1990 to 2000 from the National Institute for Road Safety, the traffic police and the Central Hospital of Maputo were reviewed. The burden of road traffic injuries in Mozambique is rising, with at least three people killed daily. The age group most affected is 25-38 (39.35%), followed by 16-24 (20.79%). The main causes of crashes include reckless driving, drunken driving, roads with potholes, inadequate signs, lack of protection for pedestrians, and inadequate traffic law enforcement. However, the data are not adequate to reveal the true magnitude of the problem. Data collected by different sources are incomplete and not coordinated with other sources and databases. In urban areas, however, better response to crashes, treatment of the injured, reporting and data collection is attributable to a greater concentration of police and medical facilities. Road traffic safety programmes in Mozambique are inadequate and inefficient, starting with the data collection system. Improvement of injury surveillance systems is needed to help make road traffic safety a national development agenda priority and for developing and implementing road safety policies. For road safety programmes to be effective, government must facilitate stakeholders' involvement, and the clear definition of government activities, civil society activities and public-private partnerships need to be established.

  1. En Route Air Traffic Control Input Devices for the Next Generation

    Science.gov (United States)

    Mainini, Matthew J.

    2010-01-01

    The purpose of this study was to investigate the usefulness of different input device configurations when trial planning new routes for aircraft in an advanced simulation of the en route workstation. The task of trial planning is one of the futuristic tools that is performed by the graphical manipulation of an aircraft's trajectory to reroute the aircraft without voice communication. In this study with two input devices, the FAA's current trackball and a basic optical computer mouse were evaluated with "pick" button in a click-and-hold state and a click-and-release state while the participant dragged the trial plan line. The trial plan was used for three different conflict types: Aircraft Conflicts, Weather Conflicts, and Aircraft + Weather Conflicts. Speed and accuracy were the primary dependent variables. Results indicate that the mouse conditions were significantly faster than the trackball conditions overall with no significant loss of accuracy. Several performance ratings and preference ratings were analyzed from post-run and post-simulation questionnaires. The release conditions were significantly more useful and likable than the hold conditions. The results suggest that the mouse in the release button state was the fastest and most well liked device configuration for trial planning in the en route workstation. Keywords-input devices, en route, controller, workstation, mouse, trackball, NextGen

  2. Unimpaired Autoreactive T-Cell Traffic Within the Central Nervous System During Tumor Necrosis Factor Receptor-Mediated inhibition of Experimental Autoimmune Encephalomyelitis

    Science.gov (United States)

    Korner, Heinrich; Goodsall, Anna L.; Lemckert, Frances A.; Scallon, Bernard J.; Ghrayeb, John; Ford, Andrew L.; Sedgwick, Jonathon D.

    1995-11-01

    The critical role of tumor necrosis factor (TNF) as a mediator in autoimmune inflammatory processes is evident from in vivo studies with TNF-blocking agents. However, the mechanisms by which TNF, and possibly also its homologue lymphotoxin α, contributes to development of pathology in rheumatoid arthritis and Crohn disease and in animal models like experimental autoimmune encephalomyelitis is unclear. Possibilities include regulation of vascular adhesion molecules enabling leukocyte movement into tissues or direct cytokine-mediated effector functions such as mediation of tissue damage. Here we show that administration of a TNF receptor (55 kDa)-IgG fusion protein prevented clinical signs of actively induced experimental autoimmune encephalomyelitis. Significantly, the total number of CD4^+ T lymphocytes isolated from the central nervous system of clinically healthy treated versus diseased control animals was comparable. By using a CD45 congenic model of passively transferred experimental autoimmune encephalomyelitis to enable tracking of myelin basic protein-specific effector T lymphocytes, prevention of clinical signs of disease was again demonstrated in treated animals but without quantitative or qualitative impediment to the movement of autoreactive T lymphocytes to and within the central nervous system. Thus, despite the uninterrupted movement of specific T lymphocytes into the target tissue, subsequent disease development was blocked. This provides compelling evidence for a direct effector role of TNF/lymphotoxin α in autoimmune tissue damage.

  3. Exploration on the Intelligent Traffic Signal Control System%智能交通信号控制系统初探

    Institute of Scientific and Technical Information of China (English)

    南楠

    2012-01-01

    城市交通拥挤是当今世界普遍关注的问题,它所带来的严重危害日益影响到人们的日常生活和社会经济的发展,而城市交通信号控制系统对解决这一问题发挥着不可替代的作用。从高性能智能交通信号控制系统的要求出发,针对目前我国城市交通问题的现状.对智能交通信号协调控制系统进行初步的研究和探讨。%The world's urban transportation issues of common concern, brings serious harm increasingly affecting people's daily life and socio-economic development, and urban traffic signal control system to solve this problem and play an irreplaceable role. Starting from the high-performance intelligent traffic signal control system requirements, for the current status of China's urban transportation problems, preliminary studies and discusses the coordination of intelligent traffic signal control system.

  4. The Design of Traffic Controller Based on VHDL Language%基于VHDL语言的交通控制器设计

    Institute of Scientific and Technical Information of China (English)

    关吉

    2014-01-01

    This paper presents a traffic controller design based on VHDL language, using QuartusII as software development plat-form, the paper focuses on the design principle and design procedure of the traffic controller. On this basis, given the realization of system source code and simulation results based on VHDL hardware description language, the simulation results further vali-date the correctness of the traffic controller program, thus demonstrating strong structural and excellent features of VHDL lan-guage.%该文介绍了一种基于VHDL语言的交通控制器设计,以QuartusII为软件开发平台,文中重点介绍该交通控制器的设计原理、设计步骤。在此基础上给出了基于VHDL硬件描述语言的系统实现源代码以及仿真结果,通过仿真结果进一步验证了该交通控制器方案的正确性,从而展示VHDL语言的强大结构和优秀特性。

  5. Large graph visualization of millions of connections in the CERN control system network traffic: analysis and design of routing and firewall rules with a new approach

    CERN Document Server

    Gallerani, Luigi

    2015-01-01

    Abstract The CERN Technical Network (TN) TN was intended to be a network for accelerator and infrastructure operations. However, today, more than 60 million IP packets are routed every hour between the General Purpose Network (GPN) and the TN, involving more than 6000 different hosts. In order to improve the security of the accelerator control system, it is fundamental to understand the network traffic between the two networks and to define new appropriate routing and firewall rules without impacting operations. The complexity and huge size of the infrastructure and the number of protocols and services involved, have discouraged for years any attempt to understand and control the network traffic between the GPN and the TN. In this paper, we show a new way to solve the problem graphically. Combining the network traffic analysis with the use of large graph visualization algorithms we produced usable 2D large color topology maps of the network identifying the inter-relations of the control system machines and s...

  6. Control of gaseous emissions in central Costanera S.A. of Argentina; Control de emisiones gaseosas en central Costanera S. A. de Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Brabenec, Edgardo [Unidad de Negocios Central Costanera, S. A., (Argentina)

    1996-12-31

    A description is presented of the equipment utilized at the Central Costanera, S.A. of Argentina, the requirements and the Environmental Management established for this Power Station, and the Standards and the resolutions and law instruments on Environmental issues. Also it is presented the Environmental Management plan of the Ente Nacional Regulador de Electricidad of Argentina as well as the controls and environmental corrective actions implemented at the Central Costanera, S.A. [Espanol] Se presenta una descripcion del equipo utilizado en la Central Costanera S.A. de Argentina, los requerimientos de gestion ambiental establecidos para esta central y las normas, resoluciones e instrumentos juridicos en materia ambiental. Se presenta ademas el plan de gestion ambiental del Ente Nacional Regulador de la Electricidad de Argentina asi como los controles y acciones correctivas ambientales implantadas en la Central Costanera S. A.

  7. Orexin, orexin receptor antagonists and central cardiovascular control

    OpenAIRE

    Carrive, Pascal

    2013-01-01

    Orexin makes an important contribution to the regulation of cardiovascular function. When injected centrally under anesthesia, orexin increases blood pressure, heart rate and sympathetic nerve activity. This is consistent with the location of orexin neurons in the hypothalamus and the distribution of orexin terminals in the central autonomic network. Thus, the two orexin receptors, Ox1R and Ox2R, which have partly overlapping distributions in the brain, are expressed in the sympathetic pregan...

  8. Study of global control of VIRGO Central Interferometer; Etude du controle global de l'Interferometre Central de VIRGO

    Energy Technology Data Exchange (ETDEWEB)

    Matone, Luca [Paris-11 Univ., 91 Orsay (France)

    1999-10-29

    The VIRGO project for the detection of gravitational waves will first operate in a test configuration, known as the Central Area Interferometer (CITF). The subject of this thesis consists of a study for the global control of this interferometer. In particular, the problems of auto-alignment and acquisition of lock are addressed. First, an investigation of the CITF optical response to longitudinal and angular mirror movements is given. On the basis of this study, we show how the ratio of photodiode signals can be used to detect and control the dark fringe when the CITF is far from its operating point (locked state). Furthermore, we present the simulation results of a quadrant photodiode configuration capable of reconstructing the mirrors' tilts once the CITF is in a locked state. The performance of a control system for the auto-alignment is then given. A study on the mode-cleaner prototype MC30 is then introduced in order to comprehend the process of lock acquisition by a linear feedback system for two different finesse values: F {approx_equal}100 and F {approx_equal} 1600. We define a threshold velocity for the mirrors' relative motion below which acquisition of lock is possible. A phenomenon, referred to as ringing effect, was observed and examined on the MC30 prototype in high finesse. The results of numerical calculations allowed us to fit measurement and estimate from them the cavity finesse as well as the mirrors' relative velocity during the resonance crossing. An empirical formula is then presented capable of determine the relative velocity from the positions of the oscillations' minima and maxima. An algorithm to guide into lock the CITF is then presented, consisting of an iterative procedure of velocity reconstruction and pulse application. A numerical calculation simulated the algorithm, the mirrors' motion, the optical response and the ADCs' process. As a result, acquisition times of the order of one second were observed: an

  9. The anti-motility signaling mechanism of TGFβ3 that controls cell traffic during skin wound healing

    Directory of Open Access Journals (Sweden)

    Arum Han

    2012-09-01

    When skin is wounded, migration of epidermal keratinocytes at the wound edge initiates within hours, whereas migration of dermal fibroblasts toward the wounded area remains undetectable until several days later. This “cell type traffic” regulation ensures proper healing of the wound, as disruptions of the regulation could either cause delay of wound healing or result in hypertrophic scars. TGFβ3 is the critical traffic controller that selectively halts migration of the dermal, but not epidermal, cells to ensure completion of wound re-epithelialization prior to wound remodeling. However, the mechanism of TGFβ3's anti-motility signaling has never been investigated. We report here that activated TβRII transmits the anti-motility signal of TGFβ3 in full to TβRI, since expression of the constitutively activated TβRI-TD mutant was sufficient to replace TGFβ3 to block PDGF-bb-induced dermal fibroblast migration. Second, the three components of R-Smad complex are all required. Individual downregulation of Smad2, Smad3 or Smad4 prevented TGFβ3 from inhibiting dermal fibroblast migration. Third, Protein Kinase Array allowed us to identify the protein kinase A (PKA as a specific downstream effector of R-Smads in dermal fibroblasts. Activation of PKA alone blocked PDGF-bb-induced dermal fibroblast migration, just like TGFβ3. Downregulation of PKA's catalytic subunit nullified the anti-motility signaling of TGFβ3. This is the first report on anti-motility signaling mechanism by TGFβ family cytokines. Significance of this finding is not only limited to wound healing but also to other human disorders, such as heart attack and cancer, where the diseased cells have often managed to avoid the anti-motility effect of TGFβ.

  10. 基于交通预测的多态交通流信号控制%Multi-state Flow Signal Control Based on Traffic Prediction

    Institute of Scientific and Technical Information of China (English)

    丁恒; 张卫华; 郑小燕; 陈无畏; 李阳阳

    2012-01-01

    The current signal control methods are insufficient in adaptability to multi-state traffic flow intersection. In order to solve this problem, on the basis of short-term traffic flow prediction, signal timing optimization for multi-state flow intersection was studied by setting multi-functional entrance lanes, vehicle detectors, lane controllers and other hardware facilities. According to the prediction data of traffic volume in intersection and signal control delay estimation model, multi-function lane flow direction was selected with the minimum total operation delay as the optimization target. Green light length was optimized gradually based on maximum queue length in every phase and signal control was implemented. Based on wavelet analysis, steady and random part of short-term traffic flow was predicted with radial basis function (RBF) neural network and Markov chain respectively. The multi-state flow signal control method at the intersection with multifunctional lanes was simulated by software VISSIM. The results show that this method can decrease the traffic delay effectively and improve service level of intersection.%为解决现有信号控制方法对多态交通流交叉口适应性不足的问题,通过在交叉口设置多功能进口车道和车辆检测器、车道控制器等硬件设施,进行了短时交通流预测基础上的多态交通流条件下交叉口信号配时优化研究。根据交通量预测数据,建立信号控制延误估计模型,以交叉口总延误最小为优化目标选取多功能车道流向,根据每相位最大排队长度逐步优化绿灯时长并实施信号控制。短时交通预测以小波分析为基础,采用RBF神经网络及Markov链分别预测交通流的稳态与随机部分。使用VISSIM软件对设置多功能车道的交叉口多态流信号控制方法进行了交通仿真。分析结果表明:该方法可有效降低行车延误,提高交叉口服务水平。

  11. Emergency vehicle traffic signal preemption system

    Science.gov (United States)

    Bachelder, Aaron D. (Inventor); Foster, Conrad F. (Inventor)

    2011-01-01

    An emergency vehicle traffic light preemption system for preemption of traffic lights at an intersection to allow safe passage of emergency vehicles. The system includes a real-time status monitor of an intersection which is relayed to a control module for transmission to emergency vehicles as well as to a central dispatch office. The system also provides for audio warnings at an intersection to protect pedestrians who may not be in a position to see visual warnings or for various reasons cannot hear the approach of emergency vehicles. A transponder mounted on an emergency vehicle provides autonomous control so the vehicle operator can attend to getting to an emergency and not be concerned with the operation of the system. Activation of a priority-code (i.e. Code-3) situation provides communications with each intersection being approached by an emergency vehicle and indicates whether the intersection is preempted or if there is any conflict with other approaching emergency vehicles. On-board diagnostics handle various information including heading, speed, and acceleration sent to a control module which is transmitted to an intersection and which also simultaneously receives information regarding the status of an intersection. Real-time communications and operations software allow central and remote monitoring, logging, and command of intersections and vehicles.

  12. [Influence of working environment factors on health state of road police officers controlling traffic (review of literature)].

    Science.gov (United States)

    Kaliaganov, P I; Troshin, V V; Makarov, I A

    2009-01-01

    The analytic review demonstrated negative influence of polluted air on respiratory diseases formation, on development of pathologic changes in neuro-endocrine and cardiovascular systems, kidneys and blood of traffic regulation officers. Special attention was put on possible carcinogenic and genotoxic influence of air polluted with chemicals in exhaust automobile gases.

  13. Traffic Signal Coordination Control of City Arterial Road%城市干道交通信号协调控制优化设计

    Institute of Scientific and Technical Information of China (English)

    周君

    2011-01-01

    以淮安市淮海南路为例,通过对淮海南路交通信号协调控制以期减少车辆的停车次数,提高车辆运行速度,减少延误,提高行车安全.通过Webster法对各进口道进行重新配时,利用干道协调控制常用方法进行各控制群的信号协调控制方案设定,再用数解法求得各交叉口信号相位差,最后通过vissim仿真得出本文干道信号协调控制方案比现行的信号控制方案更为优越.%In order to reduce the number of vehicle parking stops , and traffic delays, and improve operating speed and travel safety,a measure can be settld by coordinating traffic signal control of the Huai'an south road, the method of Webster is used to set signal control plan, then use the method of arterial road coordination control to map out each signal coordination control program, then algebraic method is used for each phase of the signal. Finally the conclusion can be gotten that the coordination control signals program is more superior than current signal control scheme by using intersection Vis-sim simulation.

  14. Traffic Generator (TrafficGen) Version 1.4.2: Users Guide

    Science.gov (United States)

    2016-06-01

    Headquarters Services , Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202...NOTES 14. ABSTRACT Network science experimentation often requires modeling of realistic network traffic specific to the experiment environment and...the network with Transmission Control Protocol and User Datagram Protocol Internet Protocol traffic. Each node generating network traffic in an

  15. 针对跑道侵入开展空管系统抵御%Against the runway intrusion to carry out air traffic control system to resist

    Institute of Scientific and Technical Information of China (English)

    赵阳

    2015-01-01

    Along with the prosperity and development of the social economy,air traffic was also people make full use of and global civil aviation transportation is more and more frequent,resulting in airport ground traffic becomes congested.The runway incursion is becoming increasingly serious,the slightest mistake will cause the plane crash tragedy.This paper introduces the definition and types of the intrusion runway, analyzes the reasons of the intrusion of the runway,and puts forward the technology leading of the air traffic control system to prevent runway intrusion and improve the safety operation level of airport runway..%随着社会经济的繁荣发展,空中交通也被人们充分地利用,全球民航业的运输交通也越来越频繁,造成机场的地面交通也随之拥挤不堪。跑道侵入的现象日益严重,稍有不慎就会会造成机毁人亡的悲剧。本文介绍侵入跑道的定义及种类,分析侵入跑道产生的原因,提出空管系统对预防跑道侵入的技术主导,改善机场跑道的安全运行水平。

  16. Design of Traffic Light System Control Based on FPGA%基于FPGA的交通灯系统控制设计

    Institute of Scientific and Technical Information of China (English)

    付铭骥

    2011-01-01

    According to the requirements of traffic light system, FPGA and Quartus Ⅱ are used to accomplish pulse formation, state timing, control flashing and time display modules of traffic lights. The simulation experiments and hardware download were carried out. The testing result meets the requirements of traffic lights. The design efficiency of digital system is significantly improved With EDA technology.%为了对交通灯系统进行精确控制,采用FPGA实验板,在QuartusⅡ软件环境下,分别实现脉冲发生模块、状态定时模块、交通灯显示模块、时间显示模块,进行仿真实验和硬件下载,获得的测试结果满足设计要求.由于采用了EDA技术,使数字系统设计的效率显著提高.

  17. Revolutionizing Technology Prioritizing Emergency Vehicles in Traffic

    Directory of Open Access Journals (Sweden)

    B. Ramya Sundaram

    2014-08-01

    Full Text Available 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 occasions. This traffic management system has proved a nuisance for the effective operation of emergency vehicles, with the public adding to the woes, as each driver races along with the signal, unmindful of the emergency vehicles. A life threatening scenario ensues when emergency vehicles get blocked by the traffic, due to inefficient traffic management system and subsequently these emergency vehicles get delayed. The existing system requires manual interruption to guide other vehicles when an emergency vehicle passes through traffic junctions. It is therefore essential to implement a self-regulating and automated system in the traffic signals to facilitate smooth movement of emergency vehicles without posing a danger to other vehicles. The innovative traffic control system devised by us provides a truly dependable alternative to monitoring traffic flow when emergency vehicles pass by.

  18. Research on central heating system control strategy based on genetic algorithm

    Science.gov (United States)

    Ding, Sa; Yang, Jianhua; Lu, Wei; Duan, Zhipeng

    2017-03-01

    The central heating is a major way of warming in northeast China in winter, however, the traditional heating method is inefficient, intensifying the energy consumption. How to improve the heating efficiency and reduce energy waste attracts more and more attentions in our country. In this paper, the mathematical model of heat transfer station temperature control system was established based on the structure of central heating system. The feedforward-feedback control strategy was used to overcome temperature fluctuations caused by the pressurized heating exchange system. The genetic algorithm was used to optimize the parameters of PID controller and simulation results demonstrated that central heating temperature achieved well control effect and meet stabilization requirements.

  19. TrafficGen Architecture Document

    Science.gov (United States)

    2016-01-01

    Poisson, Jitter, and Clone . Researchers can experience an added dimension of network traffic visualization by pairing TrafficGen with the NRL Scripted...MVC Classes The top-level MVC classes control the workspace of the application, specifically the menu and the way the nodes and events are rendered...This is a container class that holds singleton instances of the view classes employed by this application. Because of the way this application is

  20. Internet Load and Traffic Balancing

    Institute of Scientific and Technical Information of China (English)

    李文正; 郭巧; 郭为民

    2005-01-01

    Load and traffic balancing for the Internet are analyzed. An intelligent domain name system(DNS) policy for the control and management of content distribution networks (CDN) is presented. An CDNs network based Urtitech IntelliDNS is built, and performance of the network in realizing traffic and load balancing is measured. It is proved that CDNs provide a valuable service and the methods are feasible.

  1. Green Wave Traffic Optimization - A Survey

    DEFF Research Database (Denmark)

    Warberg, Andreas; Larsen, Jesper; Jørgensen, Rene Munk

    The objective of this survey is to cover the research in the area of adaptive traffic control with emphasis on the applied optimization methods. The problem of optimizing traffic signals can be viewed in various ways, depending on political, economic and ecological goals. The survey highlights some......-based, approach, which is shown to be more suitable for adaptive traffic control. To support this claim three adaptive systems, which use alternatives to the classical optimization procedures, are described in detail....

  2. Research on some key techniques to improve the reliability of air traffic control system%提高空管系统可靠性的若干关键技术的探究

    Institute of Scientific and Technical Information of China (English)

    卢昌鹏

    2015-01-01

    With the rapid development of the aviation industry in China,air traffic safety problem has become the focus of the people,air traffic control system becomes the important factor of air traffic safety..As the aviation disaster has occurred in recent years,it has also sounded the alarm for the safety of air traffic control in China..Therefore,we should greatly strengthen the air traffic safety management, improve the safety and reliability of the air traffic control system.The reliability of air traffic control system can prevent the occurrence of air accidents in the greatest degree..This paper mainly explores some key technologies of the reliability of air traffic control system,and hopes to provide theoretical support for aviation security in China..%随着我国航空行业的迅猛发展,空中交通安全问题也成为人们关注的焦点,空管系统成为空中交通安全问题的重要制约因素。随着近段时间各国以来航空灾难的不断发生,也为我国的空管安全敲响了警钟。因此,我国要大大加强空中交通安全管理,提升空管系统的安全性和可靠性。具有可靠性的空管系统技术可以在最大程度上预防空中安全事故的发生。本文主要对有关空管系统可靠性的若干关键技术进行了探究,希望能为我国航空安全提供理论上的支持。

  3. Central cholinergic control of vasopressin release in conscious rats

    Energy Technology Data Exchange (ETDEWEB)

    Iitake, K.; Share, L.; Ouchi, Y.; Crofton, J.T.; Brooks, D.P.

    1986-08-01

    Intracerebroventricular (icv) administration of carbachol into conscious rats evoked a substantial increase in vasopressin secretion and blood pressure in a dose-dependent manner. These effects were blocked by pretreatment with the muscarinic blocker, atropine (10 g icv), but not by the nicotinic blocker, hexamethonium (10 g icv). Hexamethonium did, however, block the increase in blood pressure, the decrease in heart rate, and they very small elevation in the plasma vasopressin concentration induced by nicotine (10 g icv). These results indicate that stimulation of either central nicotinic or muscarinic receptors can affect the cardiovascular system and suggest that the cholinergic stimulation of vasopressin secretion may involve primarily muscarinic receptors in the conscious rat.

  4. Networks and their traffic in multiplayer games

    Directory of Open Access Journals (Sweden)

    Cristian Andrés Melo López

    2016-06-01

    Full Text Available Computer games called multiplayer real-time, or (MCG are at the forefront of the use of the possibilities of the network. Research on this subject have been made for military simulations, virtual reality systems, computer support teamwork, the solutions diverge on the problems posed by MCG. With this in mind, this document provides an overview of the four issues affecting networking at the MCG. First, network resources (bandwidth, latency and computing capacity, together with the technical limits within which the MCG must operate. Second, the distribution concepts include communication architectures (peer-to-peer, client / server, server / network, and data and control architectures (centralized, distributed and reproduced .Thirdly, scalability allows the MCG to adapt to changes in parameterization resources. Finally, security is intended to fend off the traps and vandalism, which are common in online games; to check traffic, particularly these games we decided to take the massively multiplayer game League of Legends, a scene corresponding to a situation of real life in a network of ADSL access network is deployed has been simulated by using NS2 Three variants of TCP, it means SACK TCP, New Reno TCP, and TCP Vegas, have been considered for the cross traffic. The results show that TCP Vegas is able to maintain a constant speed while racing against the game traffic, since it avoids the packet loss and the delays in the tail caused by high peaks, without increasing the size of the sender window. SACK TCP and TCP New Reno, on the other hand, tend to increase continuously the sender window size, which could allow a greater loss of packages and also to cause unwanted delays for the game traffic.

  5. The frontoparietal control system: A central role in mental health

    Science.gov (United States)

    Cole, Michael W.; Repovs, Grega; Anticevic, Alan

    2014-01-01

    Recent findings suggest the existence of a frontoparietal control system consisting of ‘flexible hubs’ that regulate distributed systems (e.g., visual, limbic, motor) according to current task goals. A growing number of studies are reporting alterations of this control system across a striking range of mental diseases. We suggest this may reflect a critical role for the control system in promoting and maintaining mental health. Specifically, we propose that this system implements feedback control to regulate symptoms as they arise (e.g., excessive anxiety reduced via regulation of amygdala), such that an intact control system is protective against a variety of mental illnesses. Consistent with this possibility, recent results indicate that several major mental illnesses involve altered brain-wide connectivity of the control system, likely altering its ability to regulate symptoms. These results suggest that this ‘immune system of the mind’ may be an especially important target for future basic and clinical research. PMID:24622818

  6. 民航空管安全文化建设探析%Establishment of the safety culture in civil aviation air traffic control

    Institute of Scientific and Technical Information of China (English)

    张健; 宋祥波; 王万乐

    2012-01-01

    Based on the objective law of civil aviation safety development, it is necessary to establish and sustain-ably improve effective means and measures on safety culture construction in civil aviation air traffic control for ensuring the continuous safety of civil aviation in China, with consideration of synthetically requirement of carrying out continuous safety concept for ATM, the requirement of reducing human errors in air traffic control and the requirement of building ATM safety management system. In-depth exploration is launched on the safety culture construction pathways, and relevant suggestions and measures are put forwarded, such as developing cultural and entertaining activities, establishing psychological training and counseling mechanism for air traffic controllers, enhancing air traffic controllers adaptability to ATM new technology. ATM safety culture establishment is the strong backing of ATC development, and effective means and measures promoting construction will become the strong safeguard of a-viation operation safety.%根据民航空管安全发展的客观规律,在综合考虑践行空管持续安全理念、减少空管人为差错、建设空管安全管理体系的基础上,提出要实现我国民航的持续安全,就要构建并不断完善空管安全文化建设的有效手段和途径.对空管安全文化建设的途径展开了深入探索,并提出了相关建议和措施,包括开展技能竞赛等文化娱乐活动、建立管制员心理培训与辅导机制、提升管制员新技术适应能力等.空管安全文化的建设是空管发展的坚强后盾,有效手段和措施建设的推进将成为航空运行安全的有力保障.

  7. 空管系统中飞行数据处理的研究与应用%Research and application of flight data processing in air traffic control system

    Institute of Scientific and Technical Information of China (English)

    赵振宇

    2015-01-01

    In recent years,with the rapid development of China's aviation industry,China has now become a veritable aviation power,but also because of this,air traffic control is facing tremendous pressure.In view of this situation,in order to meet the demand of the healthy development of the aviation industry, China needs to construct and proficient in use of air traffic control system(hereinafter referred to as the air traffic control system),in order to effectively alleviate the pressure of air traffic control,raise the level of traffic control.This paper takes air traffic control system as the research center,and analyzes the research and application of flight data processing in air traffic control system,aiming at providing security for flight safety.%近年来,伴随着我国航空事业的迅猛发展,我国现已成为名副其实的航空大国,也正因如此,空中交通管制面临着巨大压力。鉴于此种情况,为了满足航空事业稳健发展的需求,我国亟需建设并娴熟应用空中交通管制系统(以下简称空管系统),以此有效缓解空中交通管制压力、提升交通管制工作水平。本文以空管系统为研究中心,重点探析空管系统中飞行数据处理的研究与应用,旨在为空中飞行的安全提供保障。

  8. 基于无线传感器网的智能交通信号控制设计%Design of intelligent traffic singal control based on wireless sensors network

    Institute of Scientific and Technical Information of China (English)

    任晓莉

    2011-01-01

    为了控制车辆在交叉路口顺畅通行,提出了一种基于无线传感器网的智能交通信号控制设计.利用传感器节点收集的交通信息,结合多Agent的协同方法,在不同的时段采用不同的路口控制模式,控制终端根据采集到的交通信息自适应地控制车辆通行时间,实现了交通信号灯的无线智能控制,从而提高车辆通行效率,实现交通信号控制的智能化、网络化.%In order to control the vehicles to pass the crossing smoothly, the design of intelligent traffic signal control based on wireless sensors network is proposed. Capturing the traffic informations by the sensor nodes, combing the cooperation method of multi-Agent, and adopting the crossing control modes in the different periods of time, the control terminal may control the vehicles' passing time adaptively. So the wireless intelligent control of the traffic signal lamp is realized, by which the vehicles' traffic efficiency is improved, and the intelligent and netting traffic control function is realized.

  9. A traffic priority language for collision-free navigation of autonomous mobile robots in dynamic environments.

    Science.gov (United States)

    Bourbakis, N G

    1997-01-01

    This paper presents a generic traffic priority language, called KYKLOFORTA, used by autonomous robots for collision-free navigation in a dynamic unknown or known navigation space. In a previous work by X. Grossmman (1988), a set of traffic control rules was developed for the navigation of the robots on the lines of a two-dimensional (2-D) grid and a control center coordinated and synchronized their movements. In this work, the robots are considered autonomous: they are moving anywhere and in any direction inside the free space, and there is no need of a central control to coordinate and synchronize them. The requirements for each robot are i) visual perception, ii) range sensors, and iii) the ability of each robot to detect other moving objects in the same free navigation space, define the other objects perceived size, their velocity and their directions. Based on these assumptions, a traffic priority language is needed for each robot, making it able to decide during the navigation and avoid possible collision with other moving objects. The traffic priority language proposed here is based on a set of primitive traffic priority alphabet and rules which compose pattern of corridors for the application of the traffic priority rules.

  10. Cell fate control in the developing central nervous system

    Energy Technology Data Exchange (ETDEWEB)

    Guérout, Nicolas; Li, Xiaofei; Barnabé-Heider, Fanie, E-mail: Fanie.Barnabe-Heider@ki.se

    2014-02-01

    The principal neural cell types forming the mature central nervous system (CNS) are now understood to be diverse. This cellular subtype diversity originates to a large extent from the specification of the earlier proliferating progenitor populations during development. Here, we review the processes governing the differentiation of a common neuroepithelial cell progenitor pool into mature neurons, astrocytes, oligodendrocytes, ependymal cells and adult stem cells. We focus on studies performed in mice and involving two distinct CNS structures: the spinal cord and the cerebral cortex. Understanding the origin, specification and developmental regulators of neural cells will ultimately impact comprehension and treatments of neurological disorders and diseases. - Highlights: • Similar mechanisms regulate cell fate in different CNS cell types and structures. • Cell fate regulators operate in a spatial–temporal manner. • Different neural cell types rely on the generation of a diversity of progenitor cells. • Cell fate decision is dictated by the integration of intrinsic and extrinsic signals.

  11. Central Control of Heat Pump for Smart Grid Purposes Tested on Single Family Houses

    DEFF Research Database (Denmark)

    Pedersen, Tom S.; Andersen, Palle; Nielsen, Kirsten M.

    2013-01-01

    A challenge in Denmark in the near future is to balance the electrical grid due to a large increase in the renewable energy production mainly from wind turbines. In this work a central control system using heat pumps in single family houses to help balancing the grid is investigated. The central...

  12. New Cancer Prevention and Control Central Institutional Review Board Established | Division of Cancer Prevention

    Science.gov (United States)

    The NCI Central Institutional Review Board (CIRB) Initiative announced the establishment of the Cancer Prevention and Control (CPC) CIRB January 14, extending the benefits of centralized review to investigators participating in clinical trials sponsored by the Division of Cancer Prevention (DCP). |

  13. 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…

  14. Cellular Automata Based Traffic Flow Simulation and Actuated Signal Control Strategy%基于CA方法的交通流数值模拟及信号灯感应控制策略研究

    Institute of Scientific and Technical Information of China (English)

    陈晨; 陈建桥

    2011-01-01

    According to the theory of cellular automata ( CA), the urban traffic flows at 4 intersections were investigated and a set of discrete equations were proposed to describe the traffic dynamics. The effect of two signal control strategies, i.e., synchronous timing control and actuated control, on traffic flow were discussed. Simulation results show that ( 1 ) the effect of signal control strategies is related to the density of traffic flow; (2) and there exists a certain range of actuated control parameters in which the efficiency of traffic flow can be optimized. Therefore, in order to ensure the efficiency of traffic flow, one the proper signal control strategy should be chosen for different global densities of traffic flow.%采用细胞自动机方法(Cellular Automata:CA)模拟含4个路口的城市道路交通流状态,并通过离散方程描述车辆的运动过程.研究了信号灯控制策略(同步定时控制及感应控制)对交通流状态的影响.数值模拟结果表明,信号灯对交通流的影响与道路中车辆密度有关,同时,感应控制参数的选取存在一合理的取值范围,可优化交通流通行效率.因此,为保证交通流的通行效率,应针对不同的车辆密度,选取适当的信号灯控制方式.

  15. CERN'S TECHNICAL CONTROL ROOM (TCR) A CENTRAL SERVICE FOR EVERYONE

    CERN Multimedia

    Mario Batz

    2002-01-01

    The Technical Control Room (TCR) monitors and operates the entire technical infrastructure of CERN 24 hours a day, 365 days a year. It registers and dispatches troubleshooting requests to the appropriate equipment services. In addition, the TCR executes first-line interventions on the entire CERN site. Troubleshooting requests are transmitted to the TCR either via a computerised control system or via the phone number '72201'. More than 10'000 such requests are dispatched and dealt with every year. The TCR's diverse field of activity concerns the following systems: electrical and fluid distribution networks, heating, cooling, ventilation, air-conditioning and gas equipment, safety and communication installations, electromechanical systems (e.g. lifts, cranes, machine tools, motorised doors), sanitary systems (leaks, sewage), control and monitoring infrastructure equipment, buildings. These systems can either be part of the administrative infrastructure, such as offices or restaurants, or part of the t...

  16. CERN'S TECHNICAL CONTROL ROOM (TCR) A CENTRAL SERVICE FOR EVERYONE

    CERN Multimedia

    Mario Batz

    2001-01-01

    The Technical Control Room (TCR) monitors and operates the entire technical infrastructure of CERN 24 hours a day, 365 days a year. It registers and dispatches troubleshooting requests to the appropriate equipment services. In addition, the TCR executes first-line interventions on the entire CERN site. Troubleshooting requests are transmitted to the TCR either via a computerised control system or via the phone number '72201'. More than 10'000 such requests are dispatched and dealt with every year. The TCR's diverse field of activity concerns the following systems: electrical and fluid distribution networks, heating, cooling, ventilation, air-conditioning and gas equipment, safety and communication installations, electromechanical systems (e.g. lifts, cranes, machine tools, motorised doors), sanitary systems (leaks, sewage), control and monitoring infrastructure equipment, buildings. These systems can either be part of the administrative infrastructure, such as offices or restaurants, or part of the t...

  17. CERN'S TECHNICAL CONTROL ROOM (TCR) A CENTRAL SERVICE FOR EVERYONE

    CERN Multimedia

    Mario Batz

    2002-01-01

    The Technical Control Room (TCR) monitors and operates the entire technical infrastructure of CERN 24 hours a day, 365 days a year. It registers and dispatches troubleshooting requests to the appropriate CERN equipment services or contractors. In addition, the TCR executes first-line interventions on the entire CERN site. Troubleshooting requests are transmitted to the TCR either via a computerised control system or via the phone number '72201'. More than 10'000 such requests are dispatched and dealt with every year. The TCR's diverse field of activity covers the following systems: electrical and fluid distribution networks, heating, cooling, ventilation, air-conditioning and gas equipment, safety and communication installations, electromechanical systems (e.g. lifts, cranes, machine tools, motorised doors), sanitary systems (leaks, sewage), control and monitoring infrastructure equipment, and buildings. These systems can either be part of the administrative infrastructure, such as offices or restaur...

  18. CERN'S TECHNICAL CONTROL ROOM (TCR) A CENTRAL SERVICE FOR EVERYONE

    CERN Multimedia

    Mario Batz / TCR Responsible

    2000-01-01

    The Technical Control Room (TCR) monitors and operates the entire technical infrastructure of CERN 24 hours a day, 365 days a year. It registers and dispatches troubleshooting requests to the appropriate equipment services. In addition, the TCR executes first-line interventions on the entire CERN site. Troubleshooting requests are transmitted to the TCR either via a computerised control system or via the phone number 72201. More than 10'000 such requests are dispatched and dealt with every year. The TCR's diverse field of activity concerns the following systems: electrical and fluid distribution networks, heating, cooling, ventilation, air-conditioning and gas equipment, safety and communication installations, electromechanical systems (e.g. lifts, cranes, machine tools, motorised doors), sanitary systems (leaks, sewage), control and monitoring infrastructure equipment, buildings. These systems can either be part of the administrative infrastructure, such as offices or restaurants, or part of the tec...

  19. CERN'S TECHNICAL CONTROL ROOM (TCR) A CENTRAL SERVICE FOR EVERYONE

    CERN Multimedia

    Mario Batz (TCR Responsible)

    2001-01-01

    The Technical Control Room (TCR) monitors and operates the entire technical infrastructure of CERN 24 hours a day, 365 days a year. It registers and dispatches troubleshooting requests to the appropriate equipment services. In addition, the TCR executes first-line interventions on the entire CERN site. Troubleshooting requests are transmitted to the TCR either via a computerised control system or via the phone number 72201. More than 10'000 such requests are dispatched and dealt with every year. The TCR's diverse field of activity concerns the following systems: electrical and fluid distribution networks, heating, cooling, ventilation, air-conditioning and gas equipment, safety and communication installations, electromechanical systems (e.g. lifts, cranes, machine tools, motorised doors), sanitary systems (leaks, sewage), control and monitoring infrastructure equipment, buildings. These systems can either be part of the administrative infrastructure, such as offices or restaurants, or part of the tec...

  20. CERN's Technical Control Room (TCR) A Central Service for Everyone

    CERN Multimedia

    Mario Batz

    2001-01-01

    The Technical Control Room (TCR) monitors and operates the entire technical infrastructure of CERN 24 hours a day, 365 days a year. It registers and dispatches troubleshooting requests to the appropriate equipment services. In addition, the TCR executes first-line interventions on the entire CERN site. Troubleshooting requests are transmitted to the TCR either via a computerised control system or via the phone number '72201'. More than 10'000 such requests are dispatched and dealt with every year. The TCR's diverse field of activity concerns the following systems: electrical and fluid distribution networks, heating, cooling, ventilation, air-conditioning and gas equipment, safety and communication installations, electromechanical systems (e.g. lifts, cranes, machine tools, motorised doors), sanitary systems (leaks, sewage), control and monitoring infrastructure equipment, buildings. These systems can either be part of the administrative infrastructure, such as offices or restaurants, or part of the t...

  1. TRANSIMS traffic flow characteristics

    CERN Document Server

    Nagel, K; Pieck, M; Donnelly, R; Barrett, C L; 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 versions of the TRANSIMS microsimulation.

  2. An Agent-Based Model for Analyzing Control Policies and the Dynamic Service-Time Performance of a Capacity-Constrained Air Traffic Management Facility

    Science.gov (United States)

    Conway, Sheila R.

    2006-01-01

    Simple agent-based models may be useful for investigating air traffic control strategies as a precursory screening for more costly, higher fidelity simulation. Of concern is the ability of the models to capture the essence of the system and provide insight into system behavior in a timely manner and without breaking the bank. The method is put to the test with the development of a model to address situations where capacity is overburdened and potential for propagation of the resultant delay though later flights is possible via flight dependencies. The resultant model includes primitive representations of principal air traffic system attributes, namely system capacity, demand, airline schedules and strategy, and aircraft capability. It affords a venue to explore their interdependence in a time-dependent, dynamic system simulation. The scope of the research question and the carefully-chosen modeling fidelity did allow for the development of an agent-based model in short order. The model predicted non-linear behavior given certain initial conditions and system control strategies. Additionally, a combination of the model and dimensionless techniques borrowed from fluid systems was demonstrated that can predict the system s dynamic behavior across a wide range of parametric settings.

  3. Topological-based bottleneck analysis and improvement strategies for traffic networks

    Institute of Scientific and Technical Information of China (English)

    WU JianJun; GAO ZiYou; SUN HuiJun

    2009-01-01

    ck,and make appropriate policies for traffic demand management.Meanwhile,the method has very important theoretical significance and practical worthiness in optimizing traffic organization,traffic control,and disposal of emergency.

  4. Sit4p/PP6 regulates ER-to-Golgi traffic by controlling the dephosphorylation of COPII coat subunits.

    Science.gov (United States)

    Bhandari, Deepali; Zhang, Jinzhong; Menon, Shekar; Lord, Christopher; Chen, Shuliang; Helm, Jared R; Thorsen, Kevin; Corbett, Kevin D; Hay, Jesse C; Ferro-Novick, Susan

    2013-09-01

    Traffic from the endoplasmic reticulum (ER) to the Golgi complex is initiated when the activated form of the GTPase Sar1p recruits the Sec23p-Sec24p complex to ER membranes. The Sec23p-Sec24p complex, which forms the inner shell of the COPII coat, sorts cargo into ER-derived vesicles. The coat inner shell recruits the Sec13p-Sec31p complex, leading to coat polymerization and vesicle budding. Recent studies revealed that the Sec23p subunit sequentially interacts with three different binding partners to direct a COPII vesicle to the Golgi. One of these binding partners is the serine/threonine kinase Hrr25p. Hrr25p phosphorylates the COPII coat, driving the membrane-bound pool into the cytosol. The phosphorylated coat cannot rebind to the ER to initiate a new round of vesicle budding unless it is dephosphorylated. Here we screen all known protein phosphatases in yeast to identify one whose loss of function alters the cellular distribution of COPII coat subunits. This screen identifies the PP2A-like phosphatase Sit4p as a regulator of COPII coat dephosphorylation. Hyperphosphorylated coat subunits accumulate in the sit4Δ mutant in vivo. In vitro, Sit4p dephosphorylates COPII coat subunits. Consistent with a role in coat recycling, Sit4p and its mammalian orthologue, PP6, regulate traffic from the ER to the Golgi complex.

  5. Controle de tráfego agrícola e atributos físicos do solo em área cultivada com cana-de-açúcar Agricultural traffic control and soil physical attributes in sugarcane areas

    Directory of Open Access Journals (Sweden)

    Antoniane Arantes de Oliveira Roque

    2010-07-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito do controle de tráfego agrícola na compactação do solo em áreas cultivadas com cana-de-açúcar no sistema de colheita mecanizada. O trabalho foi realizado em delineamento de blocos ao acaso, em parcelas subsubdivididas com os tratamentos: colheita mecanizada tradicional; corte mecanizado com controle de tráfego; e corte mecanizado com controle de tráfego e uso do piloto automático. Os atributos físicos do solo foram avaliados nas camadas de 0,0-0,1, 0,1-0,2 e 0,2-0,3 m de profundidade, na linha de plantio, no local em que o rodado passa e no entrerrodado. Avaliaram-se também os efeitos desses tratamentos sobre a produtividade da cana-de-açucar, respectivamente. O tráfego das máquinas agrícolas aumenta a densidade do solo e diminui o diâmetro médio ponderado dos agregados e a macroporosidade na linha de rodado em relação à linha de plantio, o que causa a degradação cumulativa da qualidade física do solo, ao longo dos anos de cultivo. Os dois anos de controle de tráfego agrícola da colheita não influenciaram os atributos físicos do solo estudados.The objective of this work was to evaluate the effect of traffic control on soil compaction in sugarcane areas with mechanical harvesting system. The study was carried out in a randomized complete block design in a split plot arrangement, with the following treatments: traditional mechanical harvesting, mechanical harvesting with traffic control, mechanical harvesting with traffic control and automatic tractor guidance. Soil physical properties were assessed at 0.0-0.1, 0.1-0.2 and 0.2-0.3-m depths, at the planting row, at the wheel tracks, and between wheel tracks. The effects of these treaments on sugarcane yield were evaluated, respectively, too. Agricultural traffic increases soil density, and reduces aggregate mean geometric diameters and macroporosity at the wheel tracks in comparison to the planting row, which leads to

  6. Peeling the Onion: Why Centralized Control / Decentralized Execution Works

    Science.gov (United States)

    2014-04-01

    tion missions are under way elsewhere in the battlespace. Moreover, there is an ongoing dynamic targeting effort against theater ballistic missiles. To...coordinating the search for theater ballistic missiles. The AWACS also provides high-value airborne-asset control, protection, and deconfliction for tankers...instead of rapidity in the context of irregular warfare. Consider the mission of Constant Hawk in Iraq where postmission forensic analysis of

  7. 城市交通拥堵传播规律与消散控制策略研究%Congestion propagation law and dissipation control strategies for urban traffic

    Institute of Scientific and Technical Information of China (English)

    高自友; 龙建成; 李新刚

    2011-01-01

    The key issue to solve urban traffic congestion is that deeply understanding the mechanism for traffic congestion formation and evolution, then make scientific manage and control strategy. In this paper, some basic concepts for urban traffic congestion, and the progress on studies for urban traffic congestion propagation and dissipation control strategies are firstly given, then the works by our group in urban traffic congestion propagation and dissipation control strategies are mainly introduced. It includes establishing the congestion propagation model by combine the micro and macro methods, analyzing the formation and evolution law of urban traffic congestion induced by accident, identifying the congestion bottleneck with high traffic demand, proposing dynamic congestion dissipation control strategies.%解决城市交通拥堵的关键是深入理解城市交通拥堵的形成机理与演变规律,从而制定科学的管理控制策略.本文首先介绍了城市交通拥堵基本概念,以及城市交通拥堵传播规律与消散策略的最新研究进展,在此基础上重点介绍了本课题组在城市交通拥堵传播规律与消散控制策略方面的研究成果.包括采用微观与宏观相结合的方法建立拥堵传播模型,分析突发事件所导致交通拥堵传播规律,交通需求增长所导致拥堵瓶颈识别,提出动态拥堵消散控制策略.

  8. Simple method of designing centralized PI controllers for multivariable systems based on SSGM.

    Science.gov (United States)

    Dhanya Ram, V; Chidambaram, M

    2015-05-01

    A method is given to design multivariable PI/PID controllers for stable and unstable multivariable systems. The method needs only the steady state gain matrix (SSGM). The method is based on the static decoupler design followed by SISO PI/PID controllers design and combining the resulted decoupler and the diagonal PI(D) controllers as the centralized controllers. The result of the present method is shown to be equivalent to the empirical method proposed by Davison EJ. Multivariable tuning regulators: the feed-forward and robust control of general servo-mechanism problem. IEEE Trans Autom Control 1976;21:35-41. Three simulation examples are given. The performance of the controllers is compared with that of the reported centralized controller based on the multivariable transfer function matrix.

  9. Central suboptimal mean-square H ∞ controller design for linear stochastic time-varying systems

    Science.gov (United States)

    Basin, Michael V.; Elvira-Ceja, Santiago; Sanchez, Edgar N.

    2011-05-01

    This article designs the central finite-dimensional H ∞ controller for linear stochastic time-varying systems with integral-quadratically bounded deterministic disturbances, that is suboptimal for a given threshold γ with respect to a modified Bolza-Meyer quadratic criterion including the attenuation control term with the opposite sign. In contrast to the previously obtained results, this article reduces the original H ∞ controller problem to the corresponding optimal H 2 controller problem, using the technique proposed in Doyle et al. (Doyle, J.C., Glover, K., Khargonekar, P.P., and Francis, B.A. (1989), 'State-space Solutions to Standard H 2 and H ∞ Control Problems', IEEE Transactions on Automatic Control, 34, 831-847). Numerical simulations are conducted to verify the performance of the designed controller for a linear stochastic system against the central suboptimal H ∞ controller available for the corresponding deterministic system.

  10. Car-following models of vehicular traffic

    Institute of Scientific and Technical Information of China (English)

    翁彦琳; 吴铁军

    2002-01-01

    The Car-following model is a kind of microscopic simulation model for vehicular traffic, which describe the one-by-one following behaviors of vehides in the same traffic lane. As a common traffic phenomenon, following behavior is of great importance in the micro-study of intelligent traffic control.Compared with other traffic-flow models, car-following model embodies the human factors and feflects the real traffic sit-uation in a better way. This paper gives a systematic review of the development and actuality of car-following models by introducing and analyzing in detail the advantages and disavantages of GHR model, OV model,CA model and fuzzy-logic model. In addition, local stability and asymptotic stability of car-following models are discussed in this paper.

  11. 11th Traffic and Granular Flow Conference

    CERN Document Server

    Daamen, Winnie

    2016-01-01

    The Conference on Traffic and Granular Flow brings together international researchers from different fields ranging from physics to computer science and engineering to discuss the latest developments in traffic-related systems. Originally conceived to facilitate new ideas by considering the similarities of traffic and granular flow, TGF'15, organised by Delft University of Technology, now covers a broad range of topics related to driven particle and transport systems. Besides the classical topics of granular flow and highway traffic, its scope includes data transport (Internet traffic), pedestrian and evacuation dynamics, intercellular transport, swarm behaviour and the collective dynamics of other biological systems. Recent advances in modelling, computer simulation and phenomenology are presented, and prospects for applications, for example to traffic control, are discussed. The conference explores the interrelations between the above-mentioned fields and offers the opportunity to stimulate interdisciplinar...

  12. Car-following models of vehicular traffic

    Institute of Scientific and Technical Information of China (English)

    翁彦琳; 吴铁军

    2002-01-01

    The Car-following models is a kind of microscopic simulation model f or vehicular traffic, which describe the one-by-one following behaviors of v ehicles in the same traffic lane. As a common traffic phenomenon, following behavior is of great importance in the micro-study of intelligent traffic control. Compared with other traffic-flow models, car-following model embodies the human factors a nd reflects the real traffic situation in a better way. This paper gives a syste matic review of the development and actuality of car-following models by introd u cing and analyzing in detail the advantages and disadvantages of GHR model, OV m odel, CA model and fuzzy-logic model. In addition, local stability and asymptot ic stability of car-following models are discussed in this paper.

  13. Using Visualization Techniques in Multilayer Traffic Modeling

    Science.gov (United States)

    Bragg, Arnold

    We describe visualization techniques for multilayer traffic modeling - i.e., traffic models that span several protocol layers, and traffic models of protocols that cross layers. Multilayer traffic modeling is challenging, as one must deal with disparate traffic sources; control loops; the effects of network elements such as IP routers; cross-layer protocols; asymmetries in bandwidth, session lengths, and application behaviors; and an enormous number of complex interactions among the various factors. We illustrate by using visualization techniques to identify relationships, transformations, and scaling; to smooth simulation and measurement data; to examine boundary cases, subtle effects and interactions, and outliers; to fit models; and to compare models with others that have fewer parameters. Our experience suggests that visualization techniques can provide practitioners with extraordinary insight about complex multilayer traffic effects and interactions that are common in emerging next-generation networks.

  14. Optimization Design of Traffic Light Control Program Based PLC%基于PLC的交通灯控制程序优化设计

    Institute of Scientific and Technical Information of China (English)

    刘爱云

    2012-01-01

    Based on Siemens S7-200 PLC instruction system for crossroads traffic lights control program design, my paper gives three different design methods which use of bit logic instruction, sequential control instruction and compare instruction. By comparing, the method which using compare instruction is more simple and easy to understand.%文章利用西门子S7 -200PLC指令系统进行十字路口交通灯控制的程序设计,给出利用位逻辑指令、顺控指令、比较指令三种不同的设计思路,通过对比,利用比较指令实现的程序,更加简单和容易理解.

  15. Traffic Flow Characteristics with Transportation Plans Components

    Directory of Open Access Journals (Sweden)

    Hrvoje Baričević

    2012-10-01

    Full Text Available Knowledge of traffic characteristics is useful to the highwayengineer in developing highway and transportation plans, performingeconomic analyses, establishing geometric design criteria,selecting and implementing traffic control measures, andevaluating the pe1[ormance of transportation facilities. Doze/ISof measures have been employed to describe the quality andquantity of traffic flow. This paper presents information onthose flow characteristics that fundamentally bear on the planning,design, and operation of highway and transport facilities:traffic speed, travel time, volume, and density.

  16. Microgrid Central Controller Development and Hierarchical Control Implementation in the Intelligent MicroGrid Lab of Aalborg University

    DEFF Research Database (Denmark)

    Meng, Lexuan; Savaghebi, Mehdi; Andrade, Fabio

    2015-01-01

    This paper presents the development of a microgrid central controller in an inverter-based intelligent microgrid (iMG) lab in Aalborg University, Denmark. The iMG lab aims to provide a flexible experimental platform for comprehensive studies of microgrids. The complete control system applied...... in this lab is based on the hierarchical control scheme for microgrids and includes primary, secondary and tertiary control. The structure of the lab, including the lab facilities, configurations and communication network, is first introduced. Primary control loops are developed in MATLAB....../Simulink and compiled to dSPACEs for local control purposes. In order to realize system supervision and proper secondary and tertiary management, a LabVIEW-based microgrid central controller is also developed. The software and hardware schemes are described. An example case is introduced and tested in the iMG lab...

  17. Road traffic injuries

    Institute of Scientific and Technical Information of China (English)

    WANG Zheng-guo 王正国

    2003-01-01

    @@ The appearance of cars has raised materialistic civilization and living standard to an unprecedented level. Today, it is hard to imagine how we human beings can live without cars.Yet, motor vehicles can cause a great number of deaths and injuries as well as considerable economic losses, which have constituted the global burden. Understanding of the occurrence and development of road traffic injuries will contribute to the prevention and control of crash and to the implementation of "everybody has the right to enjoy health" proposed by WHO.

  18. The potential of Connecterd Cruise Control in the Netherlands

    NARCIS (Netherlands)

    Klunder, G.A.; Jonkers, E.; Woldeab, Z.T.

    2013-01-01

    This paper presents the in-car advisory system Connected Cruise Control. The system gives advice – which is determined in a central back office based on the traffic state – to the driver, in order to prevent or solve suboptimal traffic flow conditions. The system aims at optimal lane distribution in

  19. Tracking with asymptotic sliding mode and adaptive input delay effect compensation of nonlinearly perturbed delayed systems applied to traffic feedback control

    Science.gov (United States)

    Mirkin, Boris; Haddad, Jack; Shtessel, Yuri

    2016-09-01

    Asymptotical sliding mode-model reference adaptive control design for a class of systems with parametric uncertainty, unknown nonlinear perturbation and external disturbance, and with known input and state delays is proposed. To overcome the difficulty to directly predict the plant state under uncertainties, a control design is based on a developed decomposition procedure, where a 'generalised error' in conjunction with auxiliary linear dynamic blocks with adjustable gains is introduced and the sliding variable is formed on the basis of this error. The effect of such a decomposition is to pull the input delay out of first step of the design procedure. As a result, similarly to the classical Smith predictor, the adaptive control architecture based only on the lumped-delays, i.e. without conventional in such cases difficult-implemented distributed-delay blocks. Two new adaptive control schemes are proposed. A linearisation-based control design is constructed for feedback control of an urban traffic region model with uncertain dynamics. Simulation results demonstrate the effectiveness of the developed adaptive control method.

  20. Central control of circadian phase in arousal-promoting neurons.

    Directory of Open Access Journals (Sweden)

    Carrie E Mahoney

    Full Text Available Cells of the dorsomedial/lateral hypothalamus (DMH/LH that produce hypocretin (HCRT promote arousal in part by activation of cells of the locus coeruleus (LC which express tyrosine hydroxylase (TH. The suprachiasmatic nucleus (SCN drives endogenous daily rhythms, including those of sleep and wakefulness. These circadian oscillations are generated by a transcriptional-translational feedback loop in which the Period (Per genes constitute critical components. This cell-autonomous molecular clock operates not only within the SCN but also in neurons of other brain regions. However, the phenotype of such neurons and the nature of the phase controlling signal from the pacemaker are largely unknown. We used dual fluorescent in situ hybridization to assess clock function in vasopressin, HCRT and TH cells of the SCN, DMH/LH and LC, respectively, of male Syrian hamsters. In the first experiment, we found that Per1 expression in HCRT and TH oscillated in animals held in constant darkness with a peak phase that lagged that in AVP cells of the SCN by several hours. In the second experiment, hamsters induced to split their locomotor rhythms by exposure to constant light had asymmetric Per1 expression within cells of the middle SCN at 6 h before activity onset (AO and in HCRT cells 9 h before and at AO. We did not observe evidence of lateralization of Per1 expression in the LC. We conclude that the SCN communicates circadian phase to HCRT cells via lateralized neural projections, and suggests that Per1 expression in the LC may be regulated by signals of a global or bilateral nature.

  1. 基于ZigBee的无线交通同步控制系统的设计与实现%Design and Realization of Wireless Synchronized Traffic Control System Based on ZigBee Technology

    Institute of Scientific and Technical Information of China (English)

    崔丽珍; 于洤

    2012-01-01

    The ZigBee agreement and the Wireless Sensor Network synchronization control algorithm were studied. A Traffic Con trol System based on ZigBee technology is proposed. The hardware node was designed based on ATmegal28L microcontroller, CC2420 RF transceiver and other chips. A wireless traffic system was improved to collect the information of the vehicle, and transfer data to traffic control center. The traffic control center sent data packets through the sink node to the wireless traffic lights. Testing results demonstrate that the system design has a good practical value.%通过研究ZigBee协议和无线传感器网络同步控制算法,提出了基于ZigBee技术的交通控制系统方案,设计了基于ATmega128L单片机、CC2420射频收发器等芯片的硬件节点,实现了无线交通系统通过对路面交通信息的采集,传输到交通指挥中心,再通过关卡节点发送数据包来对交通信号灯进行无线控制.研究及实验结果表明该设计在实际生活中具有很好的实用价值.

  2. Lyapunov-Based Control Scheme for Single-Phase Grid-Connected PV Central Inverters

    NARCIS (Netherlands)

    Meza, C.; Biel, D.; Jeltsema, D.; Scherpen, J. M. A.

    2012-01-01

    A Lyapunov-based control scheme for single-phase single-stage grid-connected photovoltaic central inverters is presented. Besides rendering the closed-loop system globally stable, the designed controller is able to deal with the system uncertainty that depends on the solar irradiance. A laboratory p

  3. Exposure to traffic-related air pollution and the risk of developing breast cancer among women in eight Canadian provinces: a case-control study.

    Science.gov (United States)

    Hystad, Perry; Villeneuve, Paul J; Goldberg, Mark S; Crouse, Dan L; Johnson, Kenneth

    2015-01-01

    A few recent studies have reported positive associations between long-term exposure to traffic-related air pollution and the incidence of breast cancer. We capitalized on an existing Canadian multi-site population-based case-control study to further investigate this association. We used the National Enhanced Cancer Surveillance System, a population-based case-control study conducted in eight of 10 Canadian provinces from 1994 to 1997. A total of 1569 breast cancer cases and 1872 population controls who reported at least 90% complete self-reported addresses over the 1975-1994 exposure period were examined. Mean exposure levels to nitrogen dioxide (NO2) (an indicator of traffic-related air pollution) were estimated for this period using three different measures: (1) satellite-derived observations; (2) satellite-derived observations scaled with historical fixed-site measurements of NO2; and (3) a national land-use regression (LUR) model. Proximity to major roads was also examined. Using unconditional logistic regression, stratified by menopausal status, we estimated odds ratios (ORs) adjusted for many individual-level and contextual breast cancer risk factors. We observed positive associations between incident breast cancer and all three measures of NO2 exposure from 1975 to 1994. In fully adjusted models for premenopausal breast cancer, a 10ppb increase in NO2 exposure estimated from the satellite-derived observations, the scaled satellite-derived observations, and the national LUR model produced ORs of 1.26 (95% confidence intervals (CIs): 0.92-1.74), 1.32 (95% CI: 1.05-1.67) and 1.28 (95% CI: 0.92-1.79). For postmenopausal breast cancer, we found corresponding ORs of 1.10 (95% CI: 0.88-1.36), 1.10 (95% CI: 0.94-1.28) and 1.07 (95% CI: 0.86-1.32). Substantial heterogeneity in the ORs was observed across the eight Canadian provinces and reduced ORs were observed when models were restricted to women who had received routine mammography examinations. No associations

  4. Traffic control and VMS collaborative technique in sudden disaster%突发灾害下交通控制与VMS协同技术

    Institute of Scientific and Technical Information of China (English)

    林赐云; 龚勃文; 赵丁选; 刘雪莲

    2012-01-01

    估计了可变信息板(VMS)的影响范围,构建了交通控制与VMS的协同一体化模型。通过VMS影响驾驶人的出行路径选择行为,引导路网交通流向最优交通流分布模式发展。通过交通控制调整交叉口信号参数,实现路网交通流的截流与分流,最终形成路网交通流最优交通分布模式。采用Frank—Wolfe均衡分配和遗传算法相结合对模型进行优化求解,利用ParamicsAPI开发模型和算法。以Paramics软件为仿真平台,以山东省淄博市淄博新区为模拟路网,在路网突发灾害下对模型和算法进行了验证。验证结果表明:路网饱和度越大,构建的模型相对于Synchro模型,提高路网交通流运行性能指标的效果越明显,促进路网交通流稳定性的能力越强,越能均衡分配路网负载。当受灾交通流疏散完成80%,路网连线饱和度分别为不大于0.8,大于0.8且不大于1.0,大于1.0时,相比Synchro模型,构建模型的受灾交通流疏散时间分别减少11.55、21.84、25.64min,疏散速度分别提高25.98%、31.83%、20.16%。%The influence scope of variable message signs(VMS) was estimated, and a collaborative model integrated of traffic control and VMS was constructed. The route choice behavior of driver was impacted by VMS, and the development of network traffic flow was guided by VMS to the optimization distribution mode. The interception and shunt of network traffic flow were fulfilled by adjusting intersection signal parameters in traffic control to form an optimal traffic flow distribution mode. The model was optimized and solved by combining Frank-Wolfe equilibrium assignment and genetic algorithm. The model and algorithm were developed by using Paramics API. In the condition of network with burst disaster, the model and algorithm were verified by taking software Paramics as simulation platform and Zibo New District of Shandong

  5. Basic study on a simulation model for the traffic stream on urban expressway merging area

    Energy Technology Data Exchange (ETDEWEB)

    Makigami, Y. [Ritsumeikan Univ., Kyoto (Japan). Faculty of Science and Engineering; Sakai, T. [Ritsumeikan Univ., Kusatsu, Shiga (Japan). Civil and Environmental SystemsJP; Ishizuka, T.

    2000-07-01

    In this study a merging traffic simulation model was developed on the results of a traffic survey covering a merging section which is located on the Central Loop of the Hanshin Expressway and often causes congestion during heavy traffic period. The merging traffic simulation model is a kind of microscopic model treating the merging model flow as compressible fluid. The merging simulation model gives very appropriate and reliable results indicating the effect of improvement plan for reducing traffic congestion. (orig.)

  6. Efficient traffic grooming with dynamic ONU grouping for multiple-OLT-based access network

    Science.gov (United States)

    Zhang, Shizong; Gu, Rentao; Ji, Yuefeng; Wang, Hongxiang

    2015-12-01

    Fast bandwidth growth urges large-scale high-density access scenarios, where the multiple Passive Optical Networking (PON) system clustered deployment can be adopted as an appropriate solution to fulfill the huge bandwidth demands, especially for a future 5G mobile network. However, the lack of interaction between different optical line terminals (OLTs) results in part of the bandwidth resources waste. To increase the bandwidth efficiency, as well as reduce bandwidth pressure at the edge of a network, we propose a centralized flexible PON architecture based on Time- and Wavelength-Division Multiplexing PON (TWDM PON). It can provide flexible affiliation for optical network units (ONUs) and different OLTs to support access network traffic localization. Specifically, a dynamic ONU grouping algorithm (DGA) is provided to obtain the minimal OLT outbound traffic. Simulation results show that DGA obtains an average 25.23% traffic gain increment under different OLT numbers within a small ONU number situation, and the traffic gain will increase dramatically with the increment of the ONU number. As the DGA can be deployed easily as an application running above the centralized control plane, the proposed architecture can be helpful to improve the network efficiency for future traffic-intensive access scenarios.

  7. Delay-bound Admission Control for Real-time Traffic in Fourth Generation IMT-Advanced Networks based on 802.16m

    Directory of Open Access Journals (Sweden)

    POUDYAL, N.

    2011-02-01

    Full Text Available In this paper a novel schedulability criteria is developed to provide Quality of Service (QoS guarantees in terms of both minimum available bandwidth and maximum tolerated packet delay as required by the real-time traffic class. The contribution makes use of a measurement based admission control scheme at the base station of the 802.16m based 4G IMT�advanced network by considering the effects of various kinds of delays including the channel access delay, queuing delay and MAC layer transmission delay on the system's end to end delay. The paper also provides a way for the mobile station to proactively increase the chances of success of bandwidth grants by predicting in advance whether its bandwidth request will be approved by the base station, and then modifying or suspending its bandwidth request in case the chances of success is not favorable at that instant.

  8. Organizational climate in air traffic control Innovative preparedness for implementation of new technology and organizational development in a rule governed organization.

    Science.gov (United States)

    Arvidsson, Marcus; Johansson, Curt R; Ek, Asa; Akselsson, Roland

    2006-03-01

    A positive and innovative organizational climate is of great importance in order to manage and adapt to change. Such a climate seldom evolves in organizations closely governed by rules and regulations. Because of ongoing organizational and technical changes within the Swedish Air Navigation Services Provider, a study concerning the organizational climate for changes and innovations was conducted to investigate the organization's capacity to cope with changes. Study locations were the two Swedish main air traffic control centers and parts of the civil aviation administration headquarters. In the study 390 subjects took part and the CCQ questionnaire was used to measure the organizational climate. The results show that the organizational climate is quite positive despite the rule-governed work. The results also show that administrative personnel assess the organizational climate as more positive than operative personnel. Comparisons between management positions did not result in any differences.

  9. A centrally controlled shuffle network for reconfigurable and fault-tolerant architecture

    OpenAIRE

    Biswas, Nripendra N; SRINIVAS, S; Dharanendra, Trishala

    1987-01-01

    The paper describes a multistage shuffle interconnection network which is controlled by a central monitor. A control code broadcast by the monitor to all the basic switching elements of the network simultaneously, makes the network dynamically reconfigurable. The control code plays three vital roles. Firstly, it establishes conflict-free paths between several source-destination pairs. Thus the problem of collision, a major obstacle of a self-routing network,is completely eliminated. Secondly,...

  10. The influence of diabetic peripheral neuropathy on local postural muscle and central sensory feedback balance control.

    Science.gov (United States)

    Toosizadeh, Nima; Mohler, Jane; Armstrong, David G; Talal, Talal K; Najafi, Bijan

    2015-01-01

    Poor balance control and increased fall risk have been reported in people with diabetic peripheral neuropathy (DPN). Traditional body sway measures are unable to describe underlying postural control mechanism. In the current study, we used stabilogram diffusion analysis to examine the mechanism under which balance is altered in DPN patients under local-control (postural muscle control) and central-control (postural control using sensory cueing). DPN patients and healthy age-matched adults over 55 years performed two 15-second Romberg balance trials. Center of gravity sway was measured using a motion tracker system based on wearable inertial sensors, and used to derive body sway and local/central control balance parameters. Eighteen DPN patients (age = 65.4±7.6 years; BMI = 29.3±5.3 kg/m2) and 18 age-matched healthy controls (age = 69.8±2.9; BMI = 27.0±4.1 kg/m2) with no major mobility disorder were recruited. The rate of sway within local-control was significantly higher in the DPN group by 49% (healthy local-controlslope = 1.23±1.06×10-2 cm2/sec, Pcontrol balance behavior in DPN patients. Unlike local-control, the rate of sway within central-control was 60% smaller in the DPN group (healthy central-controlslope-Log = 0.39±0.23, Pcontrol rate of sway with neuropathy severity (rPearson = 0.65-085, Pcontrols. However, as soon as they perceived the magnitude of sway using sensory feedback, they chose a high rigid postural control strategy, probably due to high concerns for fall, which may increase the energy cost during extended period of standing; the adaptation mechanism using sensory feedback depends on the level of neuropathy and the history of diabetes.

  11. Subjective safety in traffic.

    NARCIS (Netherlands)

    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 reason

  12. 基于隐形传态的网络流量控制研究%Network traffic control based on quantum teleportation2

    Institute of Scientific and Technical Information of China (English)

    胡晓欢; 周小清; 李智伟; 朱聿蔚

    2016-01-01

    Based on the classical channel to facilitate control indirectly to control quantum channel. By setting up two virtual circuit list amended rules:Rule 1 and Rule 2, to control the virtual circuit list. Control of the information flat of quantum channel by recompose virtual circuit list, to control quantum network traffic.%文章通过对经典信道施加控制间接对量子信道进行控制。通过设立两个虚电路列表修改规则:规则1与规则2,控制节点中虚电路列表的添加与删除。通过虚电路列表控制间接控制量子信道的信息发送平率,从而达到对量子网络的流量进行控制。

  13. The application of electronics in traffic risk control. Contribution to CEC / ECMT / COST International Seminar Electronics and traffic on major roads; Technical, reglementary and ergonomic aspects, Paris, 4-6 June 1985, Session 3: Assessment, Preprints, pp. 133-145

    NARCIS (Netherlands)

    Wouters, P.I.J.

    1985-01-01

    The introduction of electronic aids in traffic offers special opportunities for alleviating tasks of both public bodies and individual road users. However, the introduction is often problematical. In this context potential and existing applications are discussed in a functional classification, base

  14. 75 FR 9014 - Notice of Availability of a Draft Environmental Assessment for a Proposed Airport Traffic Control...

    Science.gov (United States)

    2010-02-26

    ... libraries: Kalamazoo Public Library, Washington Square Branch, 1244 Portage Street, Kalamazoo, MI 49001. Kalamazoo Public Library, Central Library, 315 S. Rose St., Kalamazoo, MI 49007. Portage District Library, 300 Library Lane, Portage, MI 49002. ] ADDRESSES: The FAA will accept written comments on the...

  15. Neurotoxicity of traffic-related air pollution.

    Science.gov (United States)

    Costa, Lucio G; Cole, Toby B; Coburn, Jacki; Chang, Yu-Chi; Dao, Khoi; Roqué, Pamela J

    2017-03-01

    The central nervous system is emerging as an important target for adverse health effects of air pollution, where it may contribute to neurodevelopmental and neurodegenerative disorders. Air pollution comprises several components, including particulate matter (PM) and ultrafine particulate matter (UFPM), gases, organic compounds, and metals. An important source of ambient PM and UFPM is represented by traffic-related air pollution, primarily diesel exhaust (DE). Human epidemiological studies and controlled animal studies have shown that exposure to air pollution, and to traffic-related air pollution or DE in particular, may lead to neurotoxicity. In particular, air pollution is emerging as a possible etiological factor in neurodevelopmental (e.g. autism spectrum disorders) and neurodegenerative (e.g. Alzheimer's disease) disorders. The most prominent effects caused by air pollution in both humans and animals are oxidative stress and neuro-inflammation. Studies in mice acutely exposed to DE (250-300μg/m(3) for 6h) have shown microglia activation, increased lipid peroxidation, and neuro-inflammation in various brain regions, particularly the hippocampus and the olfactory bulb. An impairment of adult neurogenesis was also found. In most cases, the effects of DE were more pronounced in male mice, possibly because of lower antioxidant abilities due to lower expression of paraoxonase 2.

  16. Bayesian Data Assimilation for Improved Modeling of Road Traffic

    NARCIS (Netherlands)

    Van Hinsbergen, C.P.Y.

    2010-01-01

    This thesis deals with the optimal use of existing models that predict certain phenomena of the road traffic system. Such models are extensively used in Advanced Traffic Information Systems (ATIS), Dynamic Traffic Management (DTM) or Model Predictive Control (MPC) approaches in order to improve the

  17. The development of area wide traffic management scenarios

    NARCIS (Netherlands)

    Van Zuylen, H.J.; Lu, S.; Li, J.; Yusen, C.

    2014-01-01

    Traffic management in cities with congestion is a big challenge with still unused opportunities. Intersection control is a corner stone but this should be done in an area-wide context. The dominant traffic process on urban roads is the traffic flow on the intersections. Spill back is a most importan

  18. Complex Road Traffic Congestion and Optimizing Control Method Simulation%复杂路段交通拥堵优化调控方法研究与仿真

    Institute of Scientific and Technical Information of China (English)

    刘美莲; 熊光洁; 吴雪

    2012-01-01

    Study the optimal control in the period of traffic congestion. The paper put forward a traffic congestion control 3cheme of twe-level anti-collision phase control algorithm. According to the complex road conditions, it set up two phases of vehicle queue length and its variation to determine the phase two-level traffic congestion. According to different road congestion, it determined more control conditions in the time domain to ensure the adjust efficiency. The simulation results show that the twe-level anti-collision control algorithm is effective to reduce the average vehi-cle delay time and improve the operation efficiency of traffic.%研究了交通拥堵时段的优化控制问题.提出一种二级防冲突相位控制算法的交通拥堵调控方案.根据复杂路况,建立两相位的车辆排队长度和变化量,确定二级相位的交通紧张度;根据不同相位的道路紧张程度,确定时域内的多点控制条件,保证调节效率.仿真结果显示,二级防冲突控制算法有效地降低了车辆平均延误时间,提高了交通运行效率.

  19. The influence of diabetic peripheral neuropathy on local postural muscle and central sensory feedback balance control.

    Directory of Open Access Journals (Sweden)

    Nima Toosizadeh

    Full Text Available Poor balance control and increased fall risk have been reported in people with diabetic peripheral neuropathy (DPN. Traditional body sway measures are unable to describe underlying postural control mechanism. In the current study, we used stabilogram diffusion analysis to examine the mechanism under which balance is altered in DPN patients under local-control (postural muscle control and central-control (postural control using sensory cueing. DPN patients and healthy age-matched adults over 55 years performed two 15-second Romberg balance trials. Center of gravity sway was measured using a motion tracker system based on wearable inertial sensors, and used to derive body sway and local/central control balance parameters. Eighteen DPN patients (age = 65.4±7.6 years; BMI = 29.3±5.3 kg/m2 and 18 age-matched healthy controls (age = 69.8±2.9; BMI = 27.0±4.1 kg/m2 with no major mobility disorder were recruited. The rate of sway within local-control was significantly higher in the DPN group by 49% (healthy local-controlslope = 1.23±1.06×10-2 cm2/sec, P<0.01, which suggests a compromised local-control balance behavior in DPN patients. Unlike local-control, the rate of sway within central-control was 60% smaller in the DPN group (healthy central-controlslope-Log = 0.39±0.23, P<0.02, which suggests an adaptation mechanism to reduce the overall body sway in DPN patients. Interestingly, significant negative correlations were observed between central-control rate of sway with neuropathy severity (rPearson = 0.65-085, P<0.05 and the history of diabetes (rPearson = 0.58-071, P<0.05. Results suggest that in the lack of sensory feedback cueing, DPN participants were highly unstable compared to controls. However, as soon as they perceived the magnitude of sway using sensory feedback, they chose a high rigid postural control strategy, probably due to high concerns for fall, which may increase the energy cost during extended period of standing; the adaptation

  20. Between Normalization and Reality:Review of Road Traffic Control System%规范与现实之间:道路交通管制制度检视

    Institute of Scientific and Technical Information of China (English)

    何湘

    2013-01-01

    The concept of traffic control which is a serious traffic administrative act ruled by Road Traffic Safety Law , has been widely misread.The analysis of the Article 39, 40 of the Road Traffic Safety Law and Article 15 of the People's Police Law helps to correctly understand this concept .The three chaos in the practical operation of the traffic control system deviate from the provi -sions of the law and have brought a lot of negative consequences , which indicates that the original concept is urgently to be thrown back;administrative philosophy is to be updated;the legal basis for administrative law enforcement is incorrect;regulations of lo-cal laws deviate the higher-level laws;and rules of the traffic control system are to be improved .%  交通管制作为《道路交通安全法》规定的一种严肃的交通行政行为,其概念被广泛误读;分析该法第39条、第40条和《人民警察法》第15条之规定,有助于对交通管制概念的正确理解;交通管制制度实践运作中的三种乱象背离了法律规定并带来了诸多消极后果。这些表明:交通管制原始概念亟待回归,行政理念尚需更新,行政执法的法律依据适用错误,地方性法规规定违反上位法,交通管制制度的规则有待完善。