246 research outputs found
Lunar contour mapping system /lucom/ final report, 5 aug. 1964 - 18 mar. 1965
Radar sensor system for acquisition of lunar surface data - Lunar contour mapping syste
On-Pavement Signing
Pavement marking legends are placed on the roadway to remind drivers of the speed limit or to slow down. Use of wording on the pavement surface is more dramatic than use of signing only, which can get lost in the clutter of a streetscape. On-pavement speed limit markings have been used to reinforce speed limits or to indicate a transition zone.
For more on this topic by these authors, see also Evaluation of Dynamic Speed Feedback Signs on Curves: A National Demonstration Project : http://www.trb.org/main/blurbs/172092.asp
Chevrons and Oversized Chevrons
Chevrons provide additional emphaÂsis and guidance for drivers. If spaced properly, chevrons can delineate the curve so drivers can interpret the sharpÂness of the curve. Table 2C-2 of the Manual on Uniform Traffic Control Devices (FHWA 2009a) recommends the size of chevron alignment (W1-8) signs by roadway type. Several agencies, including the Iowa Department of Transportation (Iowa DOT), have applied a larger chevron size to a roadway than suggested by this table. The idea is that larger chevrons will be more prominent and visible to drivers. These larger chevÂrons may be particularly useful if sight distance issues exist
Vertical Delineation
Vertical delineators are intended to warn drivers of an approaching curve while providing them with a better appreciation of the sharpness of a curve. Drivers can then select an appropriate speed before entering the curve. Delineation can also provide continuous tracking information once drivers are within the curve to help position their vehicles within the travel lane while traversing the curve. The most common type of vertical delineation is post mounted delineators (PMDs). These devices are usually flexible or rigid posts with some amount of reflective surface mounted along the roadside to provide additional delineation. Another treatment that has been used is to provide additional delineation on chevron posts
Evaluation of Low Cost Traffic Calming for Rural Communities – Phase II [Updated]
The main goal of the research described in this report was to evaluate countermeasures that agencies can use to reduce speeds as drivers enter rural communities located on high-speed roadways. The objectives of this study were as follows: * Identify and summarize countermeasures used to manage speeds in transition zones * Demonstrate the effectiveness of countermeasures that are practical for high- to low-speed transition zones * Acquire additional information about countermeasures that may show promise but lack sufficient evidence of effectiveness * Develop an application toolbox to assist small communities in selecting appropriate transition zones and effective countermeasures for entrances to small rural communities The team solicited small communities that were interested in participating in the Phase II study and several communities were also recommended. The treatments evaluated were selected by carefully considering traffic-calming treatments that have been used effectively in other countries for small rural communities, as well as the information gained from the first phase of the project. The treatments evaluated are as follows: * Transverse speed bars * Colored entrance treatment * Temporary island * Radar-activated speed limit sign * Speed feedback sign The toolbox publication and four focused tech briefs also cover the results of this work
Transverse Speed Bars for Rural Traffic Calming
Small rural communities often lack the expertise and resources necessary to address speeding and the persistent challenge of slowing high-speed through traffic. The entrances to communities are especially problematic given that drivers must transition from a high-speed, often-rural roadway setting to a low-speed community setting.
A number of traffic-calming devices were evaluated to determine their effectiveness in reducing speeds along the main road through a small rural community. Five different treatments were selected and installed in six rural Iowa communities. This tech brief highlights use of transverse speed bars
Speed Management Toolbox for Rural Communities
The primary objective of this toolbox is to summarize various known traffic-calming treatments and their effectiveness. This toolbox focuses on roadway-based treatments for speed management, particularly for rural communities with transition zones. Education, enforcement, and policy strategies should also be considered, but are not the focus of this toolbox. The research team identified treatments based on their own research, a review of the literature, and discussion with other professionals. This toolbox describes each treatment and summarizes placement, advantages, disadvantages, effectiveness, appropriateness, and cost for each treatment. The categories of treatments covered in this toolbox are as follows: horizontal physical displacement, vertical physical displacement, narrowing, surroundings, pavement markings, traffic control signs, and other strategies. Separate 3- to 4-page Tech Briefs for various aspects of this toolbox are attached to this record: Center Islands with Raised Curbing for Rural Traffic Calming, Colored Entrance Treatments for Rural Traffic Calming, Dynamic Speed Feedback Signs for Rural Traffic Calming, Transverse Speed Bars for Rural Traffic Calming. This toolbox and the tech briefs are related to the report Evaluation of Low Cost Traffic Calming for Rural Communities – Phase II, which is also included in this record or can be found at http://publications.iowa.gov/id/eprint/1476
Center Island with Raised Curbing for Rural Traffic Calming
Small rural communities often lack the expertise and resources necessary to address speeding and the persistent challenge of slowing high-speed through traffic. The entrances to communities are especially problematic given that drivers must transition from a high-speed, often-rural roadway setting to a low-speed community setting.
A number of traffic-calming devices were evaluated to determine their effectiveness in reducing speeds along the main road through a small rural community. Five different treatments were selected and installed in six rural Iowa communities. This tech brief highlights use of temporary curbing to create center islands
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A Statistical Study of the use of the "Mystic Chord" in the First Four Piano Sonatas of Alexander Scriabine
The purpose of this paper is to discover the environmental characteristics of the "Mystic Chord" in the first four Sonatas for Piano by Alexander Scriabine. This paper explores the manner of approach, manner of resolution, harmonic function, position, melodic function, and rhythmic position of the "Mystic Chord"
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