Field tests for evaluating cooperative intersection signal violation warning system (CISVWS)

The rear-end collision warning system requires reliable warning decision mechanism to adapt the actual driving situation. To overcome the shortcomings of existing warning methods, an adaptive strategy is proposed to address the practical aspects of the collision warning problem. The proposed strategy is based on the parameter-adaptive and variable-threshold approaches. First, several key parameter estimation algorithms are developed to provide more accurate and reliable information for subsequent warning method. They include a two-stage algorithm which contains a Kalman filter and a Luenberger observer for relative acceleration estimation, a Bayesian theory-based algorithm of estimating the road friction coefficient, and an artificial neural network for estimating the driver’s reaction time. Further, the variable-threshold warning method is designed to achieve the global warning decision. In the method, the safety distance is employed to judge the dangerous state. The calculation method of the safety distance in this paper can be adaptively adjusted according to the different driving conditions of the leading vehicle. Due to the real-time estimation of the key parameters and the adaptive calculation of the warning threshold, the strategy can adapt to various road and driving conditions. Finally, the proposed strategy is evaluated through simulation and field tests. The experimental results validate the feasibility and effectiveness of the proposed strategy.

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Empirical Analysis of Safe Distance Calculation by the Stereoscopic Capturing and Processing of Images Through the Tailigator System

Sensors ◽

10.3390/s19225044 ◽

2019 ◽

Vol 19 (22) ◽

pp. 5044

Author(s):

Gerd Christian Krizek ◽

Rene Hausleitner ◽

Laura Böhme ◽

Cristina Olaverri-Monreal

Keyword(s):

Low Cost ◽

Field Tests ◽

Warning System ◽

Collision Warning ◽

The Road ◽

Cost System ◽

Straight Line ◽

Real Value ◽

On The Road ◽

Forward Collision Warning

Driver disregard for the minimum safety distance increases the probability of rear-end collisions. In order to contribute to active safety on the road, we propose in this work a low-cost Forward Collision Warning system that captures and processes images. Using cameras located in the rear section of a leading vehicle, this system serves the purpose of discouraging tailgating behavior from the vehicle driving behind. We perform in this paper the pertinent field tests to assess system performance, focusing on the calculated distance from the processing of images and the error margins in a straight line, as well as in a curve. Based on the evaluation results, the current version of the Tailigator can be used at speeds up to 50 km per hour without any restrictions. The measurements showed similar characteristics both on the straight line and in the curve. At close distances, between 3 and 5 m, the values deviated from the real value. At average distances, around 10 to 15 m, the Tailigator achieved the best results. From distances higher than 20 m, the deviations increased steadily with the distance. We contribute to the state of the art with an innovative low-cost system to identify tailgating behavior and raise awareness, which works independently of the rear vehicle’s communication capabilities or equipment.

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Progressive failure of a constrained creeping landslide

Proceedings of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rspa.2011.0063 ◽

2011 ◽

Vol 467 (2133) ◽

pp. 2444-2461 ◽

Cited By ~ 11

Author(s):

Alexander M. Puzrin ◽

Andreas Schmid

Keyword(s):

Slip Surface ◽

Pore Water Pressure ◽

Progressive Failure ◽

Water Pressure ◽

Field Tests ◽

Warning System ◽

Earth Pressure ◽

Compression Zone ◽

Slowing Down ◽

In The Beginning

The ski resort town of St Moritz, Switzerland, is partially constructed on a large creeping landslide, which has been causing damage to buildings and infrastructure. At the town centre, the landslide is constrained by a rock outcrop, creating a compression zone in the sliding mass. After decades of gradual slowing down,s in the beginning of 1990s the landslide started to accelerate, in spite of the fact that the average yearly precipitation and the pore water pressure on the sliding surface remained fairly constant. The paper shows that a constrained creeping landslide experiences progressive failure caused by the propagation of a zone of intense shearing along the slip surface resulting in significant earth pressure increase and visco-plastic yielding of soil in the compression zone. This basic physical mechanism, relying on extensive laboratory and field tests and long-term displacement monitoring, explains the paradox of the St Moritz landslide acceleration. Although the model predicts that the landslide could eventually slow down, its displacements may become excessive for some buildings, requiring an early warning system and further stabilization of the historic Leaning Tower. In general, by predicting the onset of yielding, the model can provide an important timeframe for stabilization of constrained landslides.

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System Integration and Field Tests for Developing In-Vehicle Dilemma Zone Warning System

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1826-08 ◽

2003 ◽

Vol 1826 (1) ◽

pp. 53-59 ◽

Cited By ~ 7

Author(s):

Young-Jun Moon ◽

Jooil Lee ◽

Yukyung Park

Keyword(s):

System Integration ◽

Red Light ◽

Field Tests ◽

Warning System ◽

Field Testing ◽

Signalized Intersections ◽

Dilemma Zone ◽

Stopping Distance ◽

Real Traffic ◽

Warning Device

The basis for system integration and field testing was developed for assessing a dilemma zone warning system for signalized intersections. The system consists of hardware (an in-vehicle warning device, roadside antenna, and traffic signal controller) and software to operate and test the integrated component warning and communications systems. Field tests were conducted in real traffic situations to test the system’s warning initiation time from the signal controller, the activation and duration of the visual and audible signals, and the warning delay, on the basis of relationships between distance variables that include the safe stopping distance and the location of roadside antenna. Findings from the field tests at two signalized intersections indicated that the system could be implemented at signalized intersections to eliminate the dilemma zone, relative to approach speeds, and to reduce red-light violations and intersection collisions by means of an in-vehicle warning device.

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Structural monitoring of a curve portion of an elevated railroad including the effects of the 19 September 2017 earthquake

Earthquake Spectra ◽

10.1177/8755293020961106 ◽

2020 ◽

Vol 36 (2_suppl) ◽

pp. 262-287

Author(s):

David Murià-Vila ◽

Baruo Daniel Aldama-Sánchez ◽

Miguel Ángel García-Illescas ◽

Abraham Roberto Sánchez-Ramírez ◽

Santiago Loera

Keyword(s):

Structural Integrity ◽

Soft Soil ◽

Structural Response ◽

Field Tests ◽

Warning System ◽

Ambient Vibration ◽

Great Earthquake ◽

Seismic Events ◽

Fundamental Frequencies ◽

Design Values

This article presents the most significant structural response parameters of a railway system analyzed with data gathered during 5 years. The structure is the instrumented curved portion of an elevated railroad that consists of a simply supported beam resting on cantilever columns on soft soil. A monitoring system was implemented to determine, within a few minutes, a preliminary structural state analyzing ambient vibration or seismic events. To assess the state of health of the structure, the response obtained from the seismic events, applying the proposed methodology, is compared with that obtained from controlled field tests conducted at the end of its construction and compared with design values. The monitoring system’s results showed minimal frequency variations caused by external works and a transitory variation of the fundamental frequencies during the 19 September 2017 great earthquake that, however, did not affect the structural integrity. The warning system showed acceptable performance, and only suggested checking the support beam-column condition.

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AUSTRALIA-JAPAN QZSS EMERGENCY WARNING SERVICE TRIAL PROJECT

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xliv-3-w1-2020-21-2020 ◽

2020 ◽

Vol XLIV-3/W1-2020 ◽

pp. 21-28

Author(s):

S. Choy ◽

Y. B. Bai ◽

S. Zlatanova ◽

A. Diakite ◽

E. Rubinov ◽

...

Keyword(s):

Field Tests ◽

Warning System ◽

Relevant Information ◽

Satellite System ◽

Ground Station ◽

Warning Message ◽

South Wales ◽

Spatial Coverage ◽

Message Structure ◽

Tsunami Warnings

Abstract. This paper provides an overview and the results of the Australia-Japan 2020 Quasi Zenith Satellite System (QZSS) Emergency Warning System trial project. The project aimed to evaluate and demonstrate the feasibility of utilising the QZSS system to support emergency warning and response in Australia. The trial has focussed on bushfire and tsunami warnings with an emphasis on the message structure and standards for incorporation on the available signal bandwidth, and the spatial coverage extent of the messages. It also aimed to address the need for a space-based communication capability in Australia, which could potentially facilitate effective emergency warning system unconstrained by the limitations of terrestrial telecommunications.A newly dedicated MobileApp was developed to decode the warning message and visualise relevant information on a map. Two messages for bushfire and tsunami warnings were generated in Australia and sent to the QZSS ground station for satellite transmission. The developed application was tested in Victoria and New South Wales. The trial was successful in the sense that the emergency warning message could be received and decoded using the QZSS enabled receivers and the dedicated MobileApp. The field tests showed that the systems are capable of delivering the required information to users with the required timeliness and completeness. Several technical issues encountered during testing can be primarily attributed to the alpha state of the app, and the specific receiver used for testing. Neither of which are considered to be significant barriers to the on-going development of an operational satellite EWS system.

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Development of Industry Standard for Pipeline Security Pre-Warning Technology

Volume 4: Pipelining in Northern and Offshore Environments; Strain-Based Design; Risk and Reliability; Standards and Regulations ◽

10.1115/ipc2012-90075 ◽

2012 ◽

Author(s):

Yunjie Li ◽

Juan Zheng ◽

Dongjie Tan ◽

Yanshuang Liu ◽

Pengchao Chen

Keyword(s):

Petroleum Industry ◽

Field Tests ◽

Warning System ◽

Signal Acquisition ◽

Long Distance ◽

Long Distance Transport ◽

Industry Standard ◽

State Administration ◽

Speed Up ◽

Standardization Process

This article describes the development of industry standard for pipeline security pre-warning (PSP) technology which is an achievement of China National Petroleum Corporation’s Eleventh Five-Year science and technology project. By comprehensive application of signal acquisition and identification technologies, the PSP system monitors the pipeline for real time and promptly warns and locates the damages caused by illegal excavation, drilling hole for oil-stealing, pipeline erosion and natural disaster. This technology applied and operated well on some long distance transport pipelines in China and was listed on the Recommendation Projects for Safe and Security by the State Administration of Work Safety in 2009. To speed up the industrial application and promotion of the PSP technology, the Oil & Gas Storage and Transportation Standardization Committee (OGSTSC) of the Petroleum Industry organized the development of the standard from which transferred the research and development results. The standardization process has taken two years and gone through five major steps: first, determining the standard range; second, researching relative standards, laws and regulations; third, carrying out field tests; fourth, drafting the specifications, finally, revision and finalizing the standard. The development of PSP standard is a typical example for OGSTSC of transferring knowledge from R&D to industrial standard and finally to end users. The PSP standard development process was finished in 2010 and the industry standard SY/T 6827 Specification for Security & pre-warning System of Oil & gas Pipeline was published in the July of 2011.

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Food Safety Security: A new Concept for Enhancing Food Safety Measures

International Journal for Vitamin and Nutrition Research ◽

10.1024/0300-9831/a000114 ◽

2012 ◽

Vol 82 (3) ◽

pp. 216-222 ◽

Cited By ~ 4

Author(s):

Venkatesh Iyengar ◽

Ibrahim Elmadfa

Keyword(s):

Food Safety ◽

Hazard Analysis ◽

Warning System ◽

Shared Responsibility ◽

Fine Tuning ◽

Strategic Action ◽

Surveillance Network ◽

Measurement Systems ◽

Critical Control Points ◽

The Impact

The food safety security (FSS) concept is perceived as an early warning system for minimizing food safety (FS) breaches, and it functions in conjunction with existing FS measures. Essentially, the function of FS and FSS measures can be visualized in two parts: (i) the FS preventive measures as actions taken at the stem level, and (ii) the FSS interventions as actions taken at the root level, to enhance the impact of the implemented safety steps. In practice, along with FS, FSS also draws its support from (i) legislative directives and regulatory measures for enforcing verifiable, timely, and effective compliance; (ii) measurement systems in place for sustained quality assurance; and (iii) shared responsibility to ensure cohesion among all the stakeholders namely, policy makers, regulators, food producers, processors and distributors, and consumers. However, the functional framework of FSS differs from that of FS by way of: (i) retooling the vulnerable segments of the preventive features of existing FS measures; (ii) fine-tuning response systems to efficiently preempt the FS breaches; (iii) building a long-term nutrient and toxicant surveillance network based on validated measurement systems functioning in real time; (iv) focusing on crisp, clear, and correct communication that resonates among all the stakeholders; and (v) developing inter-disciplinary human resources to meet ever-increasing FS challenges. Important determinants of FSS include: (i) strengthening international dialogue for refining regulatory reforms and addressing emerging risks; (ii) developing innovative and strategic action points for intervention {in addition to Hazard Analysis and Critical Control Points (HACCP) procedures]; and (iii) introducing additional science-based tools such as metrology-based measurement systems.

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