Ultraviolet Headlamp Technology for Nighttime Enhancement of Roadway Markings and Pedestrians

1998 ◽  
Vol 1636 (1) ◽  
pp. 124-131 ◽  
Author(s):  
Dan Turner ◽  
Marsha Nitzburg ◽  
Richard Knoblauch
Keyword(s):  
Field Study ◽  
Traffic Control ◽  
Performance Test ◽  
Motor Vehicle ◽  
Research Effort ◽  
Subjective Evaluation ◽  
The United States ◽  
Static Tests ◽  
Pavement Markings ◽  
Instrumented Vehicle

Motorists driving at night are two to three times more likely to be involved in a crash than during the day. Although, about half of the motor vehicle deaths occur at night, death rates based on miles driven are about four times higher at night than during the day. Nighttime driving also frustrates a large number of people, the majority of which are seniors. There is an effort under way to evaluate the use of supplemental ultraviolet (UV) automobile headlights to increase nighttime visibility. Research conducted in Sweden has shown very promising results, and a preliminary field research effort recently completed in the United States found that the visibility of pavement markings increased 25 percent with UV, and subjects generally favored its use. An extensive field study was conducted to determine the conditions under which driver performance could be improved with fluorescent traffic control devices and auxiliary UV headlights. Several static tests were done to evaluate fluorescent pavement markings, post-mounted delineators, and various pedestrian scenes under two headlight conditions (low beam only and low beam with UV). Dynamic tests included a subjective evaluation of two headlamp conditions and a performance test in which subjects drove an instrumented vehicle. The results of the field study indicated that pavement markings could be observed 30 percent further, and pedestrians could be observed over 90 percent further with the addition of UV. Subjects consistently evaluated the use of UV headlamps as beneficial.

Studying the Nighttime Visibility Performance of Retroreflective Pavement Markers

2019 ◽  
Vol 2673 (9) ◽  
pp. 334-344
Author(s):  
Fan Ye ◽  
Adam Pike
Keyword(s):  
Traffic Control ◽  
The United States ◽  
Performance Criterion ◽  
Visual Performance ◽  
Performance Criteria ◽  
Pavement Markings ◽  
Driving Speed ◽  
Study Results ◽  
State And Local ◽  
Local Agencies

Retroreflective pavement markers (RPMs) supplement or substitute for pavement markings and provide superior visibility during wet nights when the visibility of most pavement markings is significantly reduced. Many state and local agencies in the United States install and maintain RPMs even though they are not required to use them by the Manual on Uniform Traffic Control Devices. A lack of visual performance criterion for in-service RPMs results in non-uniform installation and maintenance of RPMs from agency to agency. There is a need to better establish guidance on the visual performance of RPMs. This paper develops a visibility level (VL) model to assess the visibility of RPMs, based on drivers’ visual demands. After validating the VL model for RPMs, the impacts of retroreflectivity, spacing, number of RPMs, glare, and driving speed on the visibility of RPMs are explored using the VL model. The study results not only confirm the superior visual performance of RPMs over pavement markings but also suggest the RPM performance criteria including placement criteria and minimum luminance/retroreflectivity levels.

Pavement Marking Retroreflectivity Requirements for Older Drivers

1996 ◽  
Vol 1529 (1) ◽  
pp. 65-70 ◽  
Author(s):  
Johnny R. Graham ◽  
Joseph K. Harrold ◽  
L. Ellis King
Keyword(s):  
Field Study ◽  
Traffic Control ◽  
Older Drivers ◽  
Subjective Ratings ◽  
Pavement Markings ◽  
Subjective Evaluations ◽  
Significant Difference ◽  
Control Devices ◽  
Traffic Control Devices ◽  
Pavement Marking

Traffic pavement markings serve to regulate, guide, and channelize traffic and supplement other traffic-control devices. Because of their retroreflective properties pavement markings are critical for guidance at night, when reference objects near the edge of the roadway are difficult to see. Nighttime luminance levels provided by pavement markings that may be adequate for younger drivers may be less than adequate for older drivers. Both subjective evaluations and quantitative measures of in-place roadway markings were made to determine minimum marking retroreflectivity levels required for older drivers. In the field study more than 85 percent of subjects aged 60 years or older rated a marking retroreflectance of 100 mcd/m2/lx as adequate or more than adequate for night conditions. This base value does not include the effects of windshields and headlights that are less than clean or the variability of individual vehicle headlight performance. A comparison between the results for older drivers and the results of a similar 1989 study of younger drivers was also made. It was found that whereas the average subjective ratings were similarly distributed relative to the retroreflectivity of pavement markings, there was a significant difference in the subjective ratings made by older and younger drivers. Older drivers consistently rated the retroreflectivity of markings lower than did younger drivers.

Investigation of Alternative Bicycle Pavement Markings with the Use of a Bicycle Simulator

2017 ◽  
Vol 2662 (1) ◽  
pp. 143-151 ◽  
Author(s):  
Henry Brown ◽  
Carlos Sun ◽  
Zhu Qing
Keyword(s):  
Traffic Control ◽  
The United States ◽  
Sustainable Transportation ◽  
Pavement Markings ◽  
Transportation Modes ◽  
Correct Location ◽  
Green Circle ◽  
To Receive

The past decade has seen increased public interest in sustainable transportation modes in the United States. However, there is a relative lack of guidance regarding standards and specifications for bicycle facilities compared with the highway mode. This project sought to address this deficiency through the investigation of alternative pavement markings for bicycle wayfinding and proper bicycle placement at signalized intersections as part of the federal Nonmotorized Transportation Pilot Program in Columbia, Missouri. This evaluation was accomplished with a bicycle simulator study and postsimulator survey with 27 participants. A network of 37 intersections with characteristics similar to intersections in Columbia was created with the ZouSim simulator. The survey included questions regarding bicycling habits and preferences for the alternative markings. For wayfinding, two alternative types of pavement markings and the signage recommended by the Manual on Uniform Traffic Control Devices (MUTCD) were evaluated. Both the survey and the simulator results indicated that the Type 2 wayfinding markings with a green circle performed better with respect to visibility and delineating the bicycle route. The bicycle placement portion of the study investigated three alternative types of markings as well as the MUTCD markings and signage to help riders position their bicycle at the correct location to receive a green signal. The bicycle placement results indicated that the Type 1 and Type 2 experimental detector markings resulted in the fewest number of missed detections, while the Type 1 marking was the preferred alternative of the survey participants.

Field Evaluation of Fluorescent Strong Yellow-Green Pedestrian Warning Signs

1996 ◽  
Vol 1538 (1) ◽  
pp. 39-46 ◽  
Author(s):  
Kenneth L. Clark ◽  
Joseph E. Hummer ◽  
Navaneet Dutt
Keyword(s):  
Traffic Control ◽  
Research Effort ◽  
Field Evaluation ◽  
The United States ◽  
Warning Signs ◽  
Experimental Methodology ◽  
Perceived Safety ◽  
Before And After ◽  
Pedestrian Accidents ◽  
Pedestrian Crossing

Recent improvements in manufacturing processes have allowed the development of a fluorescent, microprismatic sign material with a unique strong yellow-green color. Although this color is listed in the Manual on Uniform Traffic Control Devices, it is currently unassigned. Pedestrian accidents continue to be a major safety problem in the United States, and the Federal Highway Administration has requested research on the application of fluorescent strong yellow-green warning signs for pedestrian, bicycle, and school crossing applications. The research effort sought to evaluate the effectiveness of fluorescent strong yellow-green pedestrian warning signs in improving safety at midblock pedestrian crossing areas, using sound experimental methodology and encompassing multiple users and varied crossing conditions in several North Carolina cities. An experimental plan with a single treatment was used (replacement of existing signs with fluorescent strong yellow-green) and followed a model of before and after with a comparison site. The measures of effectiveness used were vehicle-pedestrian conflicts and motorist slowing and stopping. Results indicate that the fluorescent strong yellow-green treatment produced only marginal improvements in perceived safety at the crossing sites. Although the occurrence of motorists slowing and stopping increased significantly at three of the seven test sites, the proportion of vehicle pedestrian conflicts did not change significantly. Based on the results it is recommended that FHWA tentatively designate fluorescent strong yellow-green for nonmotorized applications until such time that long-term accident-based and cost-effectiveness research is available to justify permanent designation or alternative uses.

Complex Solution of Ecological and Economic Problems of Traffic Jams

2019 ◽  
pp. 6-15
Author(s):  
Oleksandr M. Matsenko ◽  
Yaroslav S. Kovalev ◽  
Olena M. Tkachenko ◽  
Yaroslava V. Chorna
Keyword(s):  
Traffic Control ◽  
Motor Vehicle ◽  
Motor Vehicles ◽  
Water Runoff ◽  
Negative Consequences ◽  
Traffic Lights ◽  
Economic Problems ◽  
Traffic Jams ◽  
Economic Sphere ◽  
Flows Over Time

The article explores the congestion level in traffic of motor vehicles and its negative environmental and economic consequences in case of Kiev. The amount of pollution from traffic jams in Kiev and the number of vehicles which got into them in 2009-2018 is analyzed. The loss of earnings on the side of automobile owners from their standby are calculated with corresponding quantitative expressions found and described. For the course of the research, the methods of system-structural and comparative analysis were used for analyzing the environmental and economic problems of modern automobile systems; methods of formal logical analysis were used for substantiating the innovative infrastructure of transport routes. Separately economic and statistical methods were used in the study for trends development, structure analysis, and estimation of the influence of road congestion on the environmental and economic sphere. Pearson test has indicated a close relationship between the number of cars in Kiev and the number of values from traffic jams in environmental and economic sphere. Solutions to this problem are offered in forms of automated traffic control systems, improvisation of organizational and technical methods for the distribution of traffic flows over time, namely reverse traffic, road junctions, smart traffic lights, road extension, and the transition to alternative modes of transport. In all countries of the world there are new research methods that affect pollutants from motor vehicles. It is proved that they are forced by the recipients. In addition, landscaping can improve landscape design, reduce greenhouse gas emissions, surface water runoff and noise pollution. In this regard the policy implication of the research are aimed to eliminate the negative consequences from the use of vehicles during traffic jams, and the necessary number of trees for planting in Kiev is calculated. Key words: motor transport, congestion, traffic jam, motor vehicle, greening, compensation effect, lost profits, losses.

scholarly journals Personal Watercraft Incident Court Decisions: The Plaintiff’s Odds?

2021 ◽  
Vol 13 (9) ◽  
pp. 5096
Author(s):  
Eui-Yul Choi ◽  
Woo Jeong Cho
Keyword(s):  
Motor Vehicle ◽  
The United States ◽  
Insurance Companies ◽  
Court Decisions ◽  
Regression Analyses ◽  
Demographic Information ◽  
Slowing Down ◽  
Personal Watercraft ◽  
Successful Adults ◽  
Significant Factors

A personal watercraft (PWC) is a vessel that uses an inboard motor powering a water jet pump as a source of power and is operated by a person sitting, standing, or kneeling. Maneuvering a PWC is different from operating a motor vehicle or boat. An obstacle cannot be avoided by slowing down and turning the watercraft; throttle power is required to turn or maneuver the PWC. The watercraft stops only by drifting or turning sharply. The study examined sixty court decisions published in LexisNexis databases of the United States over the last decade. Cases included individuals injured while operating a PWC as a driver, passenger, or as a result of contact with a watercraft. A content analysis identified items to be used in the study. Crosstab and logistic regression analyses were used to identify demographic information and the characteristics of those who succeeded in a court of law. One-third of the cases were successful; adults, males, and the party who sustained a severe injury were more successful in a court of law with the exception of the statistically significant factors (high risk maneuvers and sharp turns). Among the additional results, we should be aware that insurance companies may not pay; additionally, it is unwise to loan a PWC to a female who has no experience.

scholarly journals Liposomal Encapsulated FSC231, a PICK1 Inhibitor, Prevents the Ischemia/Reperfusion-Induced Degradation of GluA2-Containing AMPA Receptors

Pharmaceutics ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 636
Author(s):  
Lindsay M. Achzet ◽  
Fanny Astruc-Diaz ◽  
Phillip H. Beske ◽  
Nicholas R. Natale ◽  
Travis T. Denton ◽  
...  
Keyword(s):  
Intracellular Calcium ◽  
Ampa Receptors ◽  
Research Effort ◽  
Ischemia Reperfusion ◽  
Glucose Deprivation ◽  
The United States ◽  
Excitatory Neurotransmitter ◽  
Protein Levels ◽  
Neurotransmitter Glutamate ◽  
Subsequent Degradation

Strokes remain one of the leading causes of disability within the United States. Despite an enormous amount of research effort within the scientific community, very few therapeutics are available for stroke patients. Cytotoxic accumulation of intracellular calcium is a well-studied phenomenon that occurs following ischemic stroke. This intracellular calcium overload results from excessive release of the excitatory neurotransmitter glutamate, a process known as excitotoxicity. Calcium-permeable AMPA receptors (AMPARs), lacking the GluA2 subunit, contribute to calcium cytotoxicity and subsequent neuronal death. The internalization and subsequent degradation of GluA2 AMPAR subunits following oxygen–glucose deprivation/reperfusion (OGD/R) is, at least in part, mediated by protein-interacting with C kinase-1 (PICK1). The purpose of the present study is to evaluate whether treatment with a PICK1 inhibitor, FSC231, prevents the OGD/R-induced degradation of the GluA2 AMPAR subunit. Utilizing an acute rodent hippocampal slice model system, we determined that pretreatment with FSC231 prevented the OGD/R-induced association of PICK1–GluA2. FSC231 treatment during OGD/R rescues total GluA2 AMPAR subunit protein levels. This suggests that the interaction between GluA2 and PICK1 serves as an important step in the ischemic/reperfusion-induced reduction in total GluA2 levels.

Effect of Changing a Traffic Control Device Color on Driver Behavior and Perception across Different Age Groups

2021 ◽  
pp. 036119812110111
Author(s):  
Hatem Abou-Senna ◽  
Mohamed El-Agroudy ◽  
Mustapha Mouloua ◽  
Essam Radwan
Keyword(s):  
Traffic Control ◽  
Traffic Management ◽  
Driving Simulator ◽  
Age Groups ◽  
The United States ◽  
Time Of Day ◽  
General Purpose ◽  
Traffic Density ◽  
Driving Conditions ◽  
And Performance

The use of express lanes (ELs) in freeway traffic management has seen increasing popularity throughout the United States, particularly in Florida. These lanes aim at making the most efficient transportation system management and operations tool to provide a more reliable trip. An important component of ELs is the channelizing devices used to delineate the separation between the ELs and the general-purpose lane. With the upcoming changes to the FHWA Manual on Uniform Traffic Control Devices, this study provided an opportunity to recommend changes affecting safety and efficiency on a nationwide level. It was important to understand the impacts on driver perception and performance in response to the color of the EL delineators. It was also valuable to understand the differences between demographics in responding to delineator colors under different driving conditions. The driving simulator was used to test the responses of several demographic groups to changes in marker color and driving conditions. Furthermore, participants were tested for several factors relevant to driving performance including visual and subjective responses to the changes in colors and driving conditions. Impacts on driver perception were observed via eye-tracking technology with changes to time of day, visibility, traffic density, roadway surface type, and, crucially, color of the delineating devices. The analyses concluded that white was the optimal and most significant color for notice of delineators across the majority of subjective and performance measures, followed by yellow, with black being the least desirable.

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