scholarly journals Dynamometer Tests to Estimate Efficiencies of Slow Moving Vehicles

2017 ◽  
Keyword(s):  
Moving Vehicles ◽  
Slow Moving

scholarly journals Operational and Safety Evaluation of Freeways with Posted Minimum Speed Limit

2010 ◽  
Author(s):  
Victor Muchuruza ◽  
Renatus Mussa
Keyword(s):  
Safety Evaluation ◽  
Maximum Speed ◽  
Speed Limit ◽  
Crash Data ◽  
Minimum Speed ◽  
Driving Speed ◽  
Moving Vehicles ◽  
Slow Moving ◽  
The Mean ◽  
The Difference

An operational and safety evaluation was conducted in relation to the posting of the minimum speed limit of 40 mph and the maximum speed limit of 70 mph on the Florida rural interstate freeway system. The results showed that 57% of the recorded vehicles exceeded the maximum speed limit. Additionally, while only 0.14% of recorded vehicles had speeds below the 40 mph posted minimum speed limit, 9% of crash-involved vehicles were estimated to have speeds below 40 mph. The overrepresentation of slow-moving vehicles in the crash data suggests that even a small proportion of under-40-mph vehicles can have negative implications on safety. Thus, regulation of vehicle speeds at the lower end of the speed distribution is equally important. The second order polynomial model developed to estimate the risk of a vehicle being involved in a crash as a function of the speed deviation from the mean speed of traffic indicated that the minimum risk occurred when the driving speed was 8 mph above the mean speed, equal to the 85th percentile speed observed in the field. Further, the Poisson regression modeling indicated that the difference between the 85th and 15th percentile speeds had a positive effect on crashes.

SLOW-MOVING VEHICLES IN SWEDISH TRAFFIC

2004 ◽  
Vol 10 (2) ◽  
pp. 121-126 ◽  
Author(s):  
S. Pinzke ◽  
P. Lundqvist
Keyword(s):  
Moving Vehicles ◽  
Slow Moving

Effect of connected and autonomous vehicles on traffic flow at a bidirectional road

2021 ◽  
Author(s):  
H. Echab ◽  
A. Khallouk ◽  
H. Ez-Zahraouy
Keyword(s):  
Traffic Flow ◽  
Autonomous Vehicles ◽  
Negative Influence ◽  
Conventional Vehicle ◽  
Cooperative Driving ◽  
Moving Vehicles ◽  
Penetration Ratio ◽  
Slow Moving ◽  
The Impact ◽  
Cv Model

The objective of this study was to investigate the impact of connected and autonomous vehicles (CAVs) on traffic flow under various parameters. For this purpose, we propose a mixed CAV and conventional vehicle (CV) model to investigate a bidirectional two-lane traffic flow under the periodic boundary condition. The traffic flux and the phase diagrams of the system in the ([Formula: see text]) area are constructed in both cases: with and without CAVs. The overtaking frequency is also calculated. The simulation findings show that the traffic capacity is greatly enhanced with the increase in the CAV penetration ratio. Owing to the cooperative driving strategy, with the increase in penetration ratio of the CAV, the portion of smooth overtaking is boosted. Furthermore, it is found that the traffic throughput is positively correlated to the speed limit of the fast vehicle where the flux increases as [Formula: see text] increases. Also, even if there is a low rate of slow moving vehicles in the system, it will have an appreciable and a significant negative influence.

Jet-Propelled Remote-Operated Underwater Vehicles Guided by Tilting Nozzles

1989 ◽  
Vol 26 (02) ◽  
pp. 131-144
Author(s):  
Sathya N. Gangadharan ◽  
Heinz L. Krein
Keyword(s):  
Circular Disk ◽  
Underwater Vehicles ◽  
Propulsion System ◽  
Stepper Motor ◽  
Innovative Design ◽  
Flow Rates ◽  
Total Head ◽  
Moving Vehicles ◽  
Slow Moving ◽  
Loss Coefficients

This paper is a study and experimental analysis of a forced jet propulsion system with tilting-type nozzles for slow-moving remotely operated underwater vehicles (ROV's). A test setup simulating the motion of the underwater vehicle was fabricated to investigate the effect of nozzle configurations on the propulsion of such vehicles. Plexiglass nozzles of different conical contraction angles (θ = 4 to 28 deg), different conical expansion angles (θ = 3 to 9 deg), and a straight cylindrical section were used in the study. Tests were carried out underwater, and the parameters measured include thrust, flow rate, angular velocity, and total head. Different circular disk type drag plates were used to simulate the drag of the vehicle underwater. Efficiency of propulsion is the criterion for comparing the performance of each nozzle. An expression for the optimum efficiency was derived neglecting the effect of inlet head recovery, which can be assumed for slow-moving vehicles. The energy loss and loss coefficients in submerged propulsion nozzles were found both theoretically and experimentally. A proposal for the fabrication and testing of an innovative design of a jet-propelled ROV guided by tilting nozzles is presented. The design uses a stepper motor for tilting the nozzles. A comparison is made between stationary and swivel-type configurations. The nozzles were tested for optimum area ratio. The propulsion system and the ROV was designed and checked for stability. The study revealed that for a range of flow rates, one particular nozzle was the most efficient compared to other nozzles.

Planning for Movement of Very Large, Slow‐Moving Vehicles

1992 ◽  
Vol 118 (3) ◽  
pp. 381-390
Author(s):  
John Morrall ◽  
Walid Abdelwahab ◽  
Al Werner
Keyword(s):  
Moving Vehicles ◽  
Slow Moving

scholarly journals Modelling vehicular behaviour using trajectory data under non-lane based heterogeneous traffic conditions

2019 ◽  
Vol 52 (4) ◽  
pp. 95-108 ◽  
Author(s):  
Hari Krishna Gaddam ◽  
K. Ramachandra Rao
Keyword(s):  
Traffic Flow ◽  
Fast Moving ◽  
Frictional Resistance ◽  
Separation Distance ◽  
Heterogeneous Traffic ◽  
Trajectory Data ◽  
Traffic Conditions ◽  
Moving Vehicles ◽  
Slow Moving ◽  
Lane Based

The present study aims to understand the interaction between different vehicle classes using various vehicle attributes and thereby obtain useful parameters for modelling traffic flow under non-lane based heterogeneous traffic conditions. To achieve this, a separate coordinate system has been developed to extract relevant data from vehicle trajectories. Statistical analysis results show that bi-modal and multi-modal distributions are accurate in representing vehicle lateral placement behaviour. These distributions help in improving the accuracy of microscopic simulation models in predicting vehicle lateral placement on carriageway. Vehicles off-centeredness behaviour with their leaders have significant impact on safe longitudinal headways which results in increasing vehicular density and capacity of roadway. Another interesting finding is that frictional clearance distance between vehicles influence their passing speed. Analysis revealed that the passing speeds of the fast moving vehicles such as cars are greatly affected by the presence of slow moving vehicles. However, slow moving vehicles does not reduce their speeds in the presence of fast moving vehicles. It is also found that gap sizes accepted by different vehicle classes are distributed according to Weibull, lognormal and 3 parameter log logistic distributions. Based on empirical observations, the study proposed a modified lateral separation distance factor and frictional resistance factor to model the non-lane heterogeneous traffic flow at macro level. It is anticipated that the outcomes of this study would help in developing a new methodology for modelling non-lane based heterogeneous traffic.

scholarly journals REAR SIDE CONSPICUITY OF HEAVY GOOD VEHICLES BASED ON LIGHTING COMPONENTS

2020 ◽  
Vol 7 (9) ◽  
pp. 72-79
Author(s):  
Siti Aishah Yahya ◽  
Nur Baitul Izati Rasli ◽  
Nor Azam Ramli ◽  
Syabiha Shith
Keyword(s):  
Rear Side ◽  
Safety Measures ◽  
High Compliance ◽  
Psychological Phenomenon ◽  
Moving Vehicles ◽  
Slow Moving ◽  
Heavy Goods Vehicles ◽  
Toll Plaza

In Malaysia, accidents that involve collisions with rigid and articulated trucks are mainly related to the conspicuity issue i.e. the issue of the conspicuity of the lighting components on heavy goods vehicles (HGVs). Thus, visibility and conspicuity must be improved because such an improvement can help drivers encounter safety measures on the psychological phenomenon. Conspicuity is the ability of a vehicle to be noticed without observers intentionally searching for it.  In Malaysia, HGVs must be equipped with lighting components for improved visibility. The study aims to analyse the percentages of lighting components that comply with the MS ISO 303:2004. This research is conducted at Jawi Toll Plaza, Nibong Tebal, Pulau Pinang from 9:00 a.m. to 5:00 p.m.  Results show that 93% of two-axle box trucks have installed rear lighting components that adhere to the standard. Meanwhile, other categories are between 38% and 91%.  In conclusion, even though Heavy Goods Vehicles recorded as having high compliance levels of the rear lighting components, the accident still occurred.  The types of crashes are based on the inadequate visibility involved when the moving vehicles are approaching the rear or sides of slow-moving or stationary vehicles at night.

Sign in / Sign up

Export Citation Format

Share Document