scholarly journals Impact of Automated Truck Platooning on the Performance of Freeway Mixed Traffic Flow

2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Seolyoung Lee ◽  
Cheol Oh ◽  
Gunwoo Lee
Keyword(s):  
Traffic Flow ◽  
Energy Savings ◽  
Automated Driving ◽  
Average Speed ◽  
The Road ◽  
Mobility Performance ◽  
Vehicle Platooning ◽  
Negative Effect ◽  
The Difference ◽  
On The Road

Vehicle platooning service through wireless communication and automated driving technology has become a reality. Vehicle platooning means that several vehicles travel like a train on the road with a minimum safety distance, which leads to the enhancement of safety, mobility, and energy savings. This study proposed a framework for exploring traffic mobility and safety performance due to the market penetration rate (MPR) of truck platoons based on microscopic traffic simulations. A platoon formation algorithm was developed and run on the VISSIM platform to simulate automated truck maneuvering. As a result of the mobility analysis, it was found that the difference in network mobility performance was not significant up to MPR 80%. Regarding the mobility performance of the truck-designated lane, it was found that the average speed was lower than in other lanes. In the truck-designated lane of the on-ramp section, the average speed was identified to be approximately 33% lower. From the viewpoint of network safety, increasing the MPR of the truck platoon has a positive effect on longitudinal safety but has a negative effect on lateral safety. The safety analysis of the truck-designated lane indicated that the speed difference by lane of MPR 100% is 2.5 times higher than that of MPR 0%. This study is meaningful in that it explores traffic flow performance on mobility and safety in the process of platoon formation. The outcomes of this study are expected to be utilized as fundamentals to support the novel traffic operation strategy in platooning environments.

Determination of Resistance to Abrasive Wear. VIII. Influence of Softeners in Tests with the Akron-Croydon and Du Pont Machines

1949 ◽  
Vol 22 (1) ◽  
pp. 259-262
Author(s):  
J. F. Morley
Keyword(s):  
Unit Area ◽  
Published Data ◽  
The Road ◽  
Abrasive Surface ◽  
Abrasive Power ◽  
The Difference ◽  
On The Road ◽  
The Right ◽  
Abrasion Testing

Abstract These experiments indicate that softeners can influence abrasion resistance, as measured by laboratory machines, in some manner other than by altering the stress-strain properties of the rubber. One possible explanation is that the softener acts as a lubricant to the abrasive surface. Since this surface, in laboratory abrasion-testing machines, is relatively small, and comes repeatedly into contact with the rubber under test, it seems possible that it may become coated with a thin layer of softener that reduces its abrasive power. It would be interesting in this connection to try an abrasive machine in which a long continuous strip of abrasive material was used, no part of it being used more than once, so as to eliminate or minimize this lubricating effect. The fact that the effect of the softener is more pronounced on the du Pont than on the Akron-Croydon machine lends support to the lubrication hypothesis, because on the former machine the rate of wear per unit area of abrasive is much greater. Thus in the present tests the volume of rubber abraded per hr. per sq. cm. of abrasive surface ranges from 0.03 to 0.11 cc. on the du Pont machine and from 0.0035 to 0.0045 cc. on the Akron-Croydon machine. On the other hand, if the softener acts as a lubricant, it would be expected to reduce considerably the friction between the abrasive and the rubber and hence the energy used in dragging the rubber over the abrasive surface. The energy figures given in the right-hand columns of Tables 1 and 3, however, show that there is relatively little variation between the different rubbers. As a test of the lubrication hypothesis, it would be of interest to vary the conditions of test so that approximately the same amount of rubber per unit area of abrasive is abraded in a given time on both machines; this should show whether the phenomena observed under the present test conditions are due solely to the difference in rate of wear or to an inherent difference in the type of wear on the two machines. This could most conveniently be done by considerably reducing the load on the du Pont machine. In the original work on this machine the load was standardized at 8 pounds, but no figures are quoted to show how abrasion loss varies with the load. As an addition to the present investigation, it is proposed to examine the effect of this variation with special reference to rubbers containing various amounts and types of softener. Published data on the influence of softeners on the road wear of tire rubbers do not indicate anything like such large effects as are shown by the du Pont machine. This throws some doubt on the value of this machine for testing tire tread rubbers, a conclusion which is confirmed by information obtained from other workers.

scholarly journals Behavioral Changes to Repeated Takeovers in Highly Automated Driving: Effects of the Takeover-Request Design and the Nondriving-Related Task Modality

2018 ◽  
Vol 61 (5) ◽  
pp. 839-849 ◽  
Author(s):  
Fabienne Roche ◽  
Anna Somieski ◽  
Stefan Brandenburg
Keyword(s):  
Subjective Experience ◽  
Vehicle Control ◽  
Behavioral Changes ◽  
Behavior Changes ◽  
Automated Driving ◽  
The Road ◽  
Gaze Patterns ◽  
On The Road ◽  
Task Modality ◽  
Highly Automated Driving

Objective: We investigated drivers’ behavior and subjective experience when repeatedly taking over their vehicles’ control depending on the design of the takeover request (TOR) and the modality of the nondriving-related task (NDRT). Background: Previous research has shown that taking over vehicle control after highly automated driving provides several problems for drivers. There is evidence that the TOR design and the NDRT modality may influence takeover behavior and that driver behavior changes with more experience. Method: Forty participants were requested to resume control of their simulated vehicle six times. The TOR design (auditory or visual-auditory) and the NDRT modality (auditory or visual) were varied. Drivers’ takeover behavior, gaze patterns, and subjective workload were recorded and analyzed. Results: Results suggest that drivers change their behavior to the repeated experience of takeover situations. An auditory TOR leads to safer takeover behavior than a visual-auditory TOR. And with an auditory TOR, the takeover behavior improves with experience. Engaging in the visually demanding NDRT leads to fewer gazes on the road than the auditory NDRT. Participants’ fixation duration on the road decreased over the three takeovers with the visually demanding NDRT. Conclusions: The results imply that (a) drivers change their behavior to repeated takeovers, (b) auditory TOR designs might be preferable over visual-auditory TOR designs, and (c) auditory demanding NDRTs allow drivers to focus more on the driving scene. Application: The results of the present study can be used to design TORs and determine allowed NDRTs in highly automated driving.

scholarly journals Accurate whole-night sleep monitoring with dry-contact ear-EEG

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Kaare B. Mikkelsen ◽  
Yousef R. Tabar ◽  
Simon L. Kappel ◽  
Christian B. Christensen ◽  
Hans O. Toft ◽  
...  
Keyword(s):  
High Performance ◽  
Well Being ◽  
Extensive Study ◽  
Sleep Monitoring ◽  
The Road ◽  
Scalp Eeg ◽  
Dry Contact ◽  
Negative Effect ◽  
On The Road

AbstractSleep is a key phenomenon to both understanding, diagnosing and treatment of many illnesses, as well as for studying health and well being in general. Today, the only widely accepted method for clinically monitoring sleep is the polysomnography (PSG), which is, however, both expensive to perform and influences the sleep. This has led to investigations into light weight electroencephalography (EEG) alternatives. However, there has been a substantial performance gap between proposed alternatives and PSG. Here we show results from an extensive study of 80 full night recordings of healthy participants wearing both PSG equipment and ear-EEG. We obtain automatic sleep scoring with an accuracy close to that achieved by manual scoring of scalp EEG (the current gold standard), using only ear-EEG as input, attaining an average Cohen’s kappa of 0.73. In addition, this high performance is present for all 20 subjects. Finally, 19/20 subjects found that the ear-EEG had little to no negative effect on their sleep, and subjects were generally able to apply the equipment without supervision. This finding marks a turning point on the road to clinical long term sleep monitoring: the question should no longer be whether ear-EEG could ever be used for clinical home sleep monitoring, but rather when it will be.

Vehicle Association and Tracking in Image Sequences Using Feature-Based Similarity Comparison

2014 ◽  
Vol 536-537 ◽  
pp. 176-179 ◽  
Author(s):  
Du Hyung Cho ◽  
M. Naushad Ali ◽  
Seok Ju Chun ◽  
Seok Lyong Lee
Keyword(s):  
Image Sequences ◽  
Similarity Comparison ◽  
Current Frame ◽  
The Road ◽  
Multiple Vehicles ◽  
Feature Based ◽  
The Difference ◽  
On The Road ◽  
Difference Operation ◽  
Object Association

Object association and tracking have attracted great attention in the computer vision. In this paper, we present an object association and tracking method for monitoring multiple vehicles on the road based on objects' visual features and the similarity comparison between them. First, we identify vehicles using the difference operation between the current frame in CCTV image sequences and the referential images that are stored in a database, and then extract various features from the vehicles identified. Finally, we associate the objects in the current frame with those in the next frames using similarity comparison, and track multiple objects over a sequence of CCTV image frames. Empirical study using CCTV images shows that our method has achieved the considerable effectiveness in tracking vehicles on the road.

scholarly journals Will Automated Vehicles Negatively Impact Traffic Flow?

2017 ◽  
Vol 2017 ◽  
pp. 1-17 ◽  
Author(s):  
S. C. Calvert ◽  
W. J. Schakel ◽  
J. W. C. van Lint
Keyword(s):  
Traffic Flow ◽  
Gradual Transition ◽  
Mixed Traffic ◽  
Limited Data ◽  
Automated Vehicles ◽  
Automated Driving ◽  
Low Level ◽  
Negative Effect ◽  
Vehicle Automation ◽  
Capacity Drop

With low-level vehicle automation already available, there is a necessity to estimate its effects on traffic flow, especially if these could be negative. A long gradual transition will occur from manual driving to automated driving, in which many yet unknown traffic flow dynamics will be present. These effects have the potential to increasingly aid or cripple current road networks. In this contribution, we investigate these effects using an empirically calibrated and validated simulation experiment, backed up with findings from literature. We found that low-level automated vehicles in mixed traffic will initially have a small negative effect on traffic flow and road capacities. The experiment further showed that any improvement in traffic flow will only be seen at penetration rates above 70%. Also, the capacity drop appeared to be slightly higher with the presence of low-level automated vehicles. The experiment further investigated the effect of bottleneck severity and truck shares on traffic flow. Improvements to current traffic models are recommended and should include a greater detail and understanding of driver-vehicle interaction, both in conventional and in mixed traffic flow. Further research into behavioural shifts in driving is also recommended due to limited data and knowledge of these dynamics.

scholarly journals FOURIER ANALYSIS OF THE TRAFFIC FLOW INTENSITY

2021 ◽  
pp. 46-59
Author(s):  
M.G. Boyarshinov ◽  
◽  
A.S. Vavilin ◽  
A.G. Shumkov ◽  
◽  
...  
Keyword(s):  
Time Series ◽  
Fourier Series ◽  
Traffic Flow ◽  
Harmonic Functions ◽  
Traffic Flows ◽  
The Road ◽  
Flow Intensity ◽  
Software And Hardware ◽  
On The Road ◽  
Amplitude Characteristics

The relevance of this work is determined by the need to find modern ways to process the information about traffic flows for regulating and controlling the movement of transport and pedestrians, to reduce congestion, road accidents, etc. The object of study is a part of road with heavy two-way traffic, equipped with a software and hardware complex that allows to measure the characteristics of the transport flow. The subject of the study is the daily intensity of the cars flow during the week, from Monday to Sunday. The purpose of this study is to analyze the amplitudes, frequencies, and periods of harmonic functions obtained by decomposing the time series of road traffic intensities to identify the main patterns of traffic flow formation. As a theoretical and methodological approach, the decomposition of the function of the traffic flow intensity in the Fourier series with respect to harmonic functions is used. The approach developed by the authors using the fast Fourier transform procedure made it possible to determine the amplitude-frequency characteristics of the time series under consideration, which is a scientific novelty of the analysis. It is proposed to use the «period-amplitude» characteristics as physically more meaningful instead of the «frequency-amplitude» dependencies traditionally used for the analysis. The processing of data obtained from software and hardware complexes allowed us to determine dependences of the car flow intensity on the road of the Perm city at different averaging intervals, to describe the features of the motor transport movement on the road under consideration. As a result of the study, the amplitude-frequency characteristics of time series are obtained. It is shown that the individual harmonics of the Fourier series expansion of the traffic flow intensity, which exhibits the properties of a random function, duplicate the periodicity of the global, local, and intermediate extremes of the original function and have similar periods. The practical significance consists in the use of the decomposition of the function of the traffic flow intensity in the Fourier series of harmonic functions for predicting traffic flows, controlling the operation of traffic lights, monitoring the operation of equipment, as well as in the reconstruction, design and construction of roads and road objects. The study will continue in the direction of obtaining, processing and determining the «period-amplitude» characteristics for time series of traffic flow intensity for other road networks.

scholarly journals Future mobility as a bio-inspired collaborative system

2021 ◽  
Author(s):  
Naroa Coretti Sanchez ◽  
Juan Múgica Gonzalez ◽  
Luis Alonso Pastor ◽  
Kent Larson
Keyword(s):  
Autonomous Vehicles ◽  
Swarm Robotics ◽  
System Level ◽  
Urban Mobility ◽  
The Road ◽  
Collaborative System ◽  
Current Trends ◽  
Vehicle Platooning ◽  
On The Road ◽  
Open Question

The current trends towards vehicle-sharing, electrification, and autonomy are predicted to transform mobility. Combined appropriately, they have the potential of significantly improving urban mobility. However, what will come after most vehicles are shared, electric, and autonomous remains an open question, especially regarding the interactions between vehicles and how these interactions will impact system-level behaviour. Inspired by nature and supported by swarm robotics and vehicle platooning models, this paper proposes a future mobility in which shared, electric, and autonomous vehicles behave as a bio-inspired collaborative system. The collaboration between vehicles will lead to a system-level behaviour analogous to natural swarms. Natural swarms can divide tasks, cluster, build together, or transport cooperatively. In this future mobility, vehicles will cluster by connecting either physically or virtually, which will enable the possibility of sharing energy, data or computational power, provide services or transfer cargo, among others. Vehicles will collaborate either with vehicles that are part of the same fleet, or with any other vehicle on the road, by finding mutualistic relationships that benefit both parties. The field of swarm robotics has already translated some of the behaviours from natural swarms to artificial systems and, if we further translate these concepts into urban mobility, exciting ideas emerge. Within mobility-related research, the coordinated movement proposed in vehicle platooning models can be seen as a first step towards collaborative mobility. This paper contributes with the proposal of a framework for future mobility that integrates current research and mobility trends in a novel and unique way.

scholarly journals Households’ Willingness to Adopt Technological and Behavioral Energy Savings Measures: An Empirical Study in The Netherlands

Energies ◽  
2019 ◽  
Vol 12 (22) ◽  
pp. 4294 ◽  
Author(s):  
Véronique Vasseur ◽  
Anne-Francoise Marique
Keyword(s):  
The Netherlands ◽  
Energy Saving ◽  
Energy Savings ◽  
The Road ◽  
Empirical Survey ◽  
Small Market ◽  
Willingness To Adopt ◽  
On The Road ◽  
Household Preferences ◽  
At Home

The aim of this paper is to investigate households’ willingness to adopt technological and behavioral energy savings measures, in their dwellings and for daily mobility. Based on the evidence that occupants’ behavior has a major impact on energy uses at home and on the road, this paper aims at investigating which determinants influence household preferences for energy-saving measures, both technical as well as behavioral ones, as well as highlighting the key determinants for adopting energy-savings measures, at the household scale. This paper will attempt to shed more light on the factors that may bridge the intention–behavior gap. The analysis is based on an empirical survey carried out in the Netherlands. Main results show that (1) behavioral energy saving measures are more acceptable than technical ones; (2) the adoption of energy savings measures at home is more likely than on the road; (3) there is a relatively small market for technical energy measures, especially through the initial investment and the low return on investment; (4) environmental aspects seem to be more important for relatively expensive technical energy measures; (5) the reason for taking technological energy measures is rather to be found in differences among socio-demographic background than in environmental concerns; and (6) comfort at home and on the road is an important explanatory variable that many respondents used to justify not implementing energy savings measures and should be investigated in further research.

scholarly journals Analysis of the advancements in real-life performance of highly automated vehicles' with regard to the road traffic safety

2018 ◽  
Vol 231 ◽  
pp. 05003 ◽  
Author(s):  
Arkadiusz Matysiak ◽  
Paula Razin
Keyword(s):  
Traffic Safety ◽  
Large Scale ◽  
Road Traffic ◽  
Real Life ◽  
Automated Vehicles ◽  
Automated Driving ◽  
The Road ◽  
Road Traffic Safety ◽  
On The Road ◽  
The Impact

The article presents the analysis of the performance of the vehicles equipped with automated driving systems (ADS) which were tested in real-life road conditions from 2015 to 2017 in the state of California. It aims at the effort to assess the impact on the road safety the continuous technological advancements in driving automation might have, based on of the first large-scale, real-life test deployments. Vehicle manufacturers and other stakeholders testing the highly automated vehicles in California are obliged to issue yearly reports which provide an insight on the test scale as well as the technology maturity. The so-called 'disengagement reports' highlight the range and number of control takeovers between the ADS and driver, which are made either based on driver's decision or information provided by the vehicle itself. The analysis of these reports allowed to investigate the development made in automated driving technology throughout the years of tests, as well as the direct or indirect influence of the external factors (e.g. various weather conditions) on the ADS performance. The results show that there is still a significant gap in reliability and safety between human drivers and highly automated vehicles which has been yet steadily decreasing due to technology advancements made while driving in the specific infrastructure and traffic conditions of California.

scholarly journals PSYCHOMOTOR AND COGNITIVE SKILLS THAT MAKE A DIFFERENCE IN TENNIS PLAYERS AT NATIONAL LEVEL

2020 ◽  
pp. 390-404
Keyword(s):  
Reaction Time ◽  
Cognitive Skills ◽  
National Level ◽  
Cognitive Model ◽  
Tennis Players ◽  
Sports Clubs ◽  
The Road ◽  
The Difference ◽  
On The Road ◽  
Materials Used

Tennis has become an extremely complex sport, with tennis players needing a team of specialists to maximise their sports performance. Performance tennis has proven that the difference between the players, in the conditions of similar technical-tactical performances, is made by the physical and mental training. Our paper aimed to investigate the subjective reality of junior tennis players in order to optimise their actions and activities by identifying a psychomotor and cognitive model of athletes ranked in the top area nationally. The research involved 75 tennis players - 40 boys and 35 girls aged between 14 and 16 years. The materials used were represented by the PSISELTEVA psychological testing system developed by the RQ Plus Company and calibrated to the Romanian population, which contains: levers, desk with buttons, pedals. The tests belonging to the computerised battery used in the research are: TRS (simple reaction time), TRD (discrimination reaction time), RCMV (intersegmental coordination), TUD (eye-hand coordination), ANALOGIE (analogical transfer), TAC (attention concentration), MT (topographical memory) and RNE (resistance to mental fatigue). Through the Mann-Whitney (U) test, significant differences were identified between the first tennis players in the national ranking and the players placed in the middle or final zone of the ranking, in terms of different psychomotor and cognitive coordinates (investigated in various environmental conditions). The results obtained are useful both for specialists working in the field of tennis (coaches, sports psychologists, physical trainers), athletes (boys and girls) aspiring on the road to great performance, but also for sports clubs.

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