scholarly journals Design of Real-Time Dynamic Reversible Lane in Intelligent Cooperative Vehicle Infrastructure System

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Lina Mao ◽  
Wenquan Li ◽  
Pengsen Hu ◽  
Guiliang Zhou ◽  
Huiting Zhang ◽  
...  
Keyword(s):  
Real Time ◽  
Service Level ◽  
Traffic Information ◽  
Control Effect ◽  
Time Service ◽  
Traffic Demand ◽  
The Real ◽  
Time Dynamic ◽  
Lane Changes ◽  
Infrastructure System

The rapidly growing traffic demand and the slowly increasing traffic supply have produced an mounting contradiction, which is mainly manifested in cities as road congestion and unbalanced bidirectional traffic flow. Most of the reversible lanes are implemented on fixed sections and fixed times and are mainly guided by ground markings, road signs, railings, and traffic police officer. It requires a lot of human and material costs. And, the control effect is lagging and inaccurate. Aiming at these problems, a real-time dynamic reversible lane scheme in the Intelligent Cooperative Vehicle Infrastructure System (CVIS) was proposed. Traffic information was collected in real time through the CVIS, and a reversible lane scheme was established based on the real-time service level V/C and BRP functions. A lane change control model was applied to determine the number of lanes and the timing of lane changes. Then, the reversible lanes were managed in real time through intelligent road stud lights and light curtain walls. Buffer sections and no-entry sections were set to ensure reversible lanes operating safely and efficiently. VISSIM simulation was used for case analysis, and the results showed that compared with the traditional time-controlled reversible lane scheme, the real-time dynamic reversible lane scheme could reduce the average vehicle delay by 27.4% and decrease the vehicle VOC, CO and NOX emissions by 13.5%.

scholarly journals Using Digital Twining in Fast-food Production Chain Simulation

2021 ◽  
Vol 343 ◽  
pp. 03005
Author(s):  
Florina Chiscop ◽  
Bogdan Necula ◽  
Carmen Cristiana Cazacu ◽  
Cristian Eugen Stoica
Keyword(s):  
Real Time ◽  
Fast Food ◽  
Virtual Model ◽  
Time Data ◽  
Production Chain ◽  
The Real ◽  
Time Dynamic ◽  
Digital Twin ◽  
Food Company ◽  
The Moment

The topic of this paper represents our research in the process of creating a virtual model (digital twin) for a fast-food company production chain starting with the moment when a customer launches an order, following with the processing of that order, until the customer receives it. The model will describe elements that are included in this process such as equipment, human resources and the necessary space that is needed to host this layout. The virtual model created in a simulation platform will be a replicate of a real fast-food company, thus helping us observe the real time dynamic of this production system. Using WITNESS HORIZON 23 we will construct the model of the layout based on real time data received from the fast-food company. This digital twin will be used to manage the production chain material flow, evaluating the performance of the system architecture in various scenarios. In order to obtain a diagnosis of the system’s performance we will simulate the workflow running through preliminary architecture in compliance with the real time behaviour to identify the bottlenecks and blockages in the flow trajectory. In the end we will propose two different optimised architectures for the fast-food company production chain.

scholarly journals Research on Optimized Control Model of Freeway Based on Dynamic Traffic Demand Estimation

2014 ◽  
Vol 6 ◽  
pp. 797293 ◽  
Author(s):  
Zhu Jiang ◽  
Shubin Li
Keyword(s):  
Optimal Control ◽  
Real Time ◽  
Demand Estimation ◽  
Control Model ◽  
Control Module ◽  
Traffic Demand ◽  
The Real ◽  
Traffic Conditions ◽  
Real Time Traffic ◽  
Global Optimal

According to the estimation information of dynamic traffic demands, a novel optimal control model of freeway was established on the basis of the hierarchical concept. There are four control modules in this model. The OD prediction module predicts the total traffic demands in a long time and determines the upper bound of the future queuing length in advance; the global optimal control module predicts the future traffic state and establishes the coordination constraints for each ramp in the network; the traffic demand estimation module estimates the real-time traffic conditions for each ramp; the local adaptive control module regulates ramp metering rate according to the estimated information of the real-time traffic conditions and the results optimized by the global optimal control module. The simulation results show that this control system is of a good dynamic performance. It coordinates the benefits of various ramps and optimizes the overall performance of the freeway network.

scholarly journals GNSS-Warp Software for Real-Time Precise Point Positioning

2015 ◽  
Vol 50 (2) ◽  
pp. 59-76 ◽  
Author(s):  
Hadaś Tomasz
Keyword(s):  
Real Time ◽  
Precise Point Positioning ◽  
Static Mode ◽  
Time Service ◽  
The Real ◽  
North East ◽  
Satellite Geometry ◽  
Point Positioning ◽  
Performance Validation ◽  
Mode A

Abstract On April 1, 2013 IGS launched the real-time service providing products for Precise Point Positioning (PPP). The availability of real-time makes PPP a very powerful technique to process GNSS signals in real-time and opens a new PPP applications opportunities. There are still, however, some limitations of PPP, especially in the kinematic mode. A significant change in satellite geometry is required to efficiently de-correlate troposphere delay, receiver clock offset, and receiver height. In order to challenge PPP limitations, the GNSS-WARP (Wroclaw Algorithms for Real-time Positioning) software has been developed from scratch at Wroclaw University of Environmental and Life Science in Poland. This paper presents the GNSS-WARP software itself and some results of GNSS data analysis using PPP and PPP-RTK (Real-Time Kinematic) technique. The results of static and kinematic processing in GPS only and GPS + GLONASS mode with final and real-time products are presented. Software performance validation in postprocessing mode confirmed that the software can be considered as a state-ofthe- art software and used for further studies on PPP algorithm development. The real-time positioning test made it possible to assess the quality of real-time coordinates, which is a few millimeters for North, East, Up in static mode, a below decimeter in kinematic mode. The accuracy and precision of height estimates in kinematic mode were improved by constraining the solution with an external, near real-time troposphere model. The software also allows estimation of real-time ZTD, however, the obtained precision of 11.2 mm means that further improvements in the software, real-time products or processing strategy are required.

Research on Real-Time Performance of the Distributed Control System Based on RTLinux

2014 ◽  
Vol 945-949 ◽  
pp. 1372-1375
Author(s):  
Peng Zhang ◽  
Qin Guo ◽  
Bin Wang
Keyword(s):  
Control System ◽  
Real Time ◽  
Robot Control ◽  
Real Time Control ◽  
Control Effect ◽  
The Real ◽  
Time Performance ◽  
Time Control ◽  
Testing Experiment ◽  
Time Systems

Through the analysis of RTLinux source code and real-time performance of various testing experiment on the RTLinux, and its application in a distributed robot control system using CAN bus, realize the real-time control of robot joints. Write the code of real-time module on RTLinux, analyzing the real-time performance using related kernel time testing function. Under Linux using QT write user interface for robot control, running on the Linux user space. The interface program and the real-time program communicate via RT-FIFO. Specify the location of each robot joint in the interface program, compared with the feedback from the actual joint position trajectory, evaluate the control effect of real-time systems.

scholarly journals Real-Time Dynamic Behavior Evaluation of Active Distribution Networks Leveraging Low-Cost PMUs

Energies ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4999
Author(s):  
Xuejun Zheng ◽  
Shaorong Wang ◽  
Xin Su ◽  
Mengmeng Xiao ◽  
Zia Ullah ◽  
...  
Keyword(s):  
Real Time ◽  
Dynamic Behavior ◽  
Low Cost ◽  
Distribution Network ◽  
Distribution Networks ◽  
Assessment Model ◽  
The Real ◽  
Time Dynamic ◽  
Dynamic Index ◽  
Active Distribution Networks

The investigation of real-time dynamic behavior evaluation in the active distribution networks (ADNs) is a challenging task, and it has great importance due to the emerging trend of distributed generations, electric vehicles, and flexible loads integration. The advent of new elements influences the dynamic behavior of the electric distribution networks and increases the assessment complexity. However, the proper implementation of low-cost phasor measurement units (PMUs) together with the development of power system applications offer tremendous benefits. Therefore, this paper proposes a PMU-based multi-dimensional dynamic index approach for real-time dynamic behavior evaluation of ADNs. The proposed evaluation model follows the assessment principles of accuracy, integrity, practicability, and adaptability. Additionally, we introduced low-cost PMUs in the assessment model and implemented them for real-time and high-precision monitoring of dynamic behaviors in the entire distribution network. Finally, a complete model called the real-time dynamic characteristics evaluation system is presented and applied to the ADN. It is pertinent to mention that our proposed evaluation methodology does not rely on the network topology or line parameters of the distribution network since only the phasor measurements of node voltage and line current are involved in the dynamic index system. Thus, the presented methodology is well adaptive to different operation states of ADN despite frequent topology changes. The validation of the proposed approach was verified by conducting simulations on the modified IEEE 123-node distribution network. The obtained results verify the effectiveness and relevance of the proposed model for the real-time dynamic behavior evaluation of ADNs.

Service Level Agreements for Real-Time Service-Oriented Infrastructures

2011 ◽  
pp. 133-159
Author(s):  
Roland Kübert ◽  
Georgina Gallizo ◽  
Theodoros Polychniatis ◽  
Theodora Varvarigou ◽  
Eduardo Oliveros ◽  
...  
Keyword(s):  
Cloud Computing ◽  
Grid Computing ◽  
Real Time ◽  
Service Level ◽  
Service Level Agreements ◽  
Real Time Systems ◽  
Service Oriented Architectures ◽  
Time Service ◽  
Service Oriented ◽  
Time Systems

Service Level Agreements (SLAs) are nowadays used as a cornerstone for building service-oriented architectures. SLAs have been closely investigated in the scope of distributed and Grid computing and are now gaining uptake in cloud computing as well. However, most solutions have been developed for specific purposes and are not applicable generally, even though the most approaches propose a general usability. Only rarely have SLAs been applied to real-time systems. The purpose of this chapter is to analyze different fields where SLAs are used, examine the proposed solutions, and investigate how these can be improved in order to better support the creation of real-time service-oriented architectures.

Service Level Agreements for Real-Time Service-Oriented Infrastructures

2012 ◽  
pp. 1836-1862 ◽  
Author(s):  
Roland Kübert ◽  
Georgina Gallizo ◽  
Thodoris Polychniatis ◽  
Theodora Varvarigou ◽  
Eduardo Oliveros ◽  
...  
Keyword(s):  
Cloud Computing ◽  
Grid Computing ◽  
Real Time ◽  
Service Level ◽  
Service Level Agreements ◽  
Real Time Systems ◽  
Service Oriented Architectures ◽  
Time Service ◽  
Service Oriented ◽  
Time Systems

Service Level Agreements (SLAs) are nowadays used as a cornerstone for building service-oriented architectures. SLAs have been closely investigated in the scope of distributed and Grid computing and are now gaining uptake in cloud computing as well. However, most solutions have been developed for specific purposes and are not applicable generally, even though the most approaches propose a general usability. Only rarely have SLAs been applied to real-time systems. The purpose of this chapter is to analyze different fields where SLAs are used, examine the proposed solutions, and investigate how these can be improved in order to better support the creation of real-time service-oriented architectures.

Early Warning of Low Frequency Oscillation and Analysis of its Related Issues

2012 ◽  
Vol 433-440 ◽  
pp. 7465-7470
Author(s):  
Chao Dong ◽  
Di Chen Liu ◽  
Zhen Chuan Du ◽  
Qing Fen Liao ◽  
Lei Yun ◽  
...  
Keyword(s):  
Real Time ◽  
Early Warning ◽  
Low Frequency ◽  
Local Maximum ◽  
Weak Links ◽  
Frequency Oscillation ◽  
Low Frequency Oscillation ◽  
The Real ◽  
Time Dynamic ◽  
Interconnected Power System

This paper set up the model of power transmissive observational section and put forward the real-time tracking method of power angle curve in steady state which could be used to identify and focus on monitoring the weak links, then to take early warnings of low frequency oscillation. On the dynamic situation of system been disturbed, we extracted the real-time dynamic damping value of the observational section, calculated its fitting curve of local maximum points and took the slope of curve as the criteria, in order to achieve early warning of low frequency oscillation under multiple disturbances in the interconnected power system.

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