Drivers' Behavior at Railroad Grade Crossings: Before and After Safety Campaign, HR-335, 1992

In April 1991 the Iowa Department of Transportation, the CNW Transportation Company, the SOO Line, and local agencies and business in the Mason City/Clear Lake area initiated an Operation Lifesaver program to attempt to increase public awareness of safety issues and safe behavior at railroad-highway grade crossings. This document reports an initial study of data on traffic characteristics at a selected set of grade crossings in Cerro Gordo County taken before and after the safety program. Twenty-two crossings were studied. The 13 crossings at which collisions were reported for the five years prior to the study were included in the sample of sites. Two field observations were made at each study crossing before the Operation Lifesaver campaign was in full swing, and two observations were made after the conclusion of the main effort of the campaign. The summary of each data set is contained in a companion volume. The research shows that Operation Lifesaver altered drivers' behavior in the following ways: (1) reduced approach speeds and crossing speeds at crossings with low speed limits, (2) reduced the percent of drivers approaching the crossing at speeds in excess of the posted speed limit, and (3) increased alertness of drivers to railroad crossing hazards as evidenced by more drivers looking for a clear track. Thus, Operation Lifesaver enhanced safety in street and highway traffic operations in the vicinity of railroad-highway grade crossings.

Analysis of Safety Benefits for Shielding of Bridge Piers, 2009

The highway system in the State of Iowa includes many grade separation structures constructed to provide maximum safety and mobility to road users on intersecting roadways. However, these structures can present possible safety concerns for traffic passing underneath due to close proximity of piers and abutments. Shielding of these potential hazards has been a design consideration for many years. This study examines historical crash experience in the State of Iowa to address the advisability of shielding bridge piers and abutments as well as other structure support elements considering the offset from the traveled way. A survey of nine Midwestern states showed that six states had bridge pier shielding practices consistent with those in Iowa. Data used for the analyses include crash data (2001 to 2007) from the Iowa Department of Transportation (Iowa DOT), the Iowa DOT’s Geographic Information Management System (GIMS) structure and roadway data (2006) obtained from the Office of Transportation Data, and shielding and offset data for the bridges of interest. Additionally, original crash reports and the Iowa DOT video log were also utilized as needed. Grade-separated structures over high-speed, multilane divided Interstate and primary highways were selected for analysis, including 566 bridges over roadways with a speed limit of at least 45 mph. Bridges that met the criteria for inclusion in the study were identified for further analysis using crash data. The study also included economic analysis for possible shielding improvement.

On-Pavement Signing, 2014

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.aspx

Sprinkle Treatments for Asphalt Concrete, HR-507, 1986

In recent years, the Iowa Department of Transportation has put greater emphasis on improving highway safety. This effort has been relatively successful with a reduction in traffic-related fatalities to levels experienced prior to 1950. The nationwide speed limit of 55 mph was probably the greatest contributor to the decline in traffic fatalities, but there have been many other efforts that have also contributed to this decline. The Iowa DOT has been testing all paved roadways periodically for friction coefficient since 1969. New techniques have been used to obtain a greater depth of surface texture on paved roadways. Transverse tined grooving has been used on portland cement concrete to provide increased texture depth.

Safety Benefits of Paved Shoulders, 2009

Single vehicle run-off-road (ROR) crashes are the largest type of fatal passenger vehicle crash in the United States (NCHRP 500 2003). In Iowa, ROR crashes accounted for 36% of rural crashes and 9% of total crashes in 2006. Run-off-road crashes accounted for more than 61.8% of rural fatal crashes and 32.6% of total fatal crashes in Iowa in 2006. Paved shoulders are a potential countermeasure for ROR crashes. Several studies are available which have generally indicated that paved shoulders are effective in reducing crashes. However, the number of studies that quantify the benefits are limited. The research described in this report evaluates the effectiveness of paved shoulders. Model results indicated that covariate for speed limit was not significant at the 0.05 confidence level and was removed from the model. All other variables which resulted in the final model were significant at the 0.05 confidence level. The final model indicated that season of the year was significant in indicating expected number of total monthly crashes with a higher number of crashes occurring in the winter and fall than for spring and summer. The model also indicated that presence of rumble strips, paved shoulder width, unpaved shoulder width, and presence of a divided median were correlated with a decrease in crashes. The model also indicated that roadway sections with paved shoulders had fewer crashes in the after period as compared to both the before period and control sections. The actual impact of paved shoulders depends on several other covariates as indicated in the final model such as installation year and width of paved shoulders. However, comparing the expected number of total crashes before and after installation of paved shoulders for several scenarios indicated around a 4.6% reduction in the expected number of monthly crashes in the after period.

Päällystyksen vaikutus paperin ja kartongin laserleikattavuuteen

Tämän diplomityön tarkoituksena oli selvittää päällystyksen vaikutusta paperin ja kartongin laserleikattavuuteen. Aiheeseen liittyi myös laserparametrien vaikutuksen selvittäminen leikattaessa päällystettyjä paperi- ja kartonkilaatuja. Päällystepigmentteinä käytettiin kalsiumkarbonaattia ja kaoliinia sekä niiden seosta. Leikkausnopeus alenee päällystyspigmentistä ja sen määrästä riippuen 5 – 20 % verrattuna saman neliöpainoisiin päällystämättömiin materiaaleihin. Yli 1000 W:n laserteholla leikkausnopeuden kasvu tehon funktiona pysähtyy kalsiumkarbonaatilla päällystetyillä kartongeilla. Päällystetyllä paperilla vastaava tehoraja on 1400 W. Polttopisteen optimi paikkaan päällystyksellä ei ole vaikutusta. Myöskään leikatun reunan laatuun päällystyksellä ei ole suurta vaikutusta. Leikkauksessa muodostuvat savut ovat pääasiassa selluloosan pilkkoutumistuotteita. Suuri osa savuista on myrkyllisiä, joten leikkauskohdan riittävästä ilmanvaihdosta on huolehdittava. Sopivilla prosessiparametreilla voidaan saada 10 – 20 %:n parannuksia leikkausnopeuteen.

Disseny d’un motllo i components per a la seva fabricació

Partint del disseny en 3D i del plànol d’una peça de plàstic, es vol fabricar un motllo d’injecció de plàstic per a la seva producció amb un bon disseny comercial i un cost acceptable per al mercat actual. La peça serà el botó/polsador “ASL” (AUTOMATIC SPEED LIMIT) del quadre de comandament del model de cotxe “JAGUAR XF”. A sota de la peça anirà un let per il•luminar les zones indicades en ambients foscos o de nit, per a la indicació a l’usuari de la seva funció i per qüestions estètiques

Is speeding a "real" antisocial behavior? A comparison with other antisocial behaviors

The relationship between speed and crashes has been well established in the literature, with the consequence that speed reduction through enforced or other means should lead to a reduction in crashes. The extent to which the public regard speeding as a problem that requires enforcement is less clear. Analysis was conducted on public perceptions of antisocial behaviors including speeding traffic. The data was collected as part of the British Crime Survey, a face-to-face interview with UK residents on issues relating to crime. The antisocial behavior section required participants to state the degree to which they perceived 16 antisocial behaviors to be a problem in their area. Results revealed that speeding traffic was perceived as the greatest problem in local communities, regardless of whether respondents were male or female, young, middle aged, or old. The rating of speeding traffic as the greatest problem in the community was replicated in a second, smaller postal survey, where respondents also provided strong support for enforcement on residential roads, and indicated that traveling immediately above the speed limit on residential roads was unacceptable. Results are discussed in relation to practical implications for speed enforcement, and the prioritization of limited police resources. (c) 2006 Elsevier Ltd. All rights reserved.

Road and Traffic Signs Recognition using Vector Machines

Intelligent Transportation System (ITS) is a system that builds a safe, effective and integrated transportation environment based on advanced technologies. Road signs detection and recognition is an important part of ITS, which offer ways to collect the real time traffic data for processing at a central facility.This project is to implement a road sign recognition model based on AI and image analysis technologies, which applies a machine learning method, Support Vector Machines, to recognize road signs. We focus on recognizing seven categories of road sign shapes and five categories of speed limit signs. Two kinds of features, binary image and Zernike moments, are used for representing the data to the SVM for training and test. We compared and analyzed the performances of SVM recognition model using different features and different kernels. Moreover, the performances using different recognition models, SVM and Fuzzy ARTMAP, are observed.

Road Sign Recognition based onInvariant Features using SupportVector Machine

Since last two decades researches have been working on developing systems that can assistsdrivers in the best way possible and make driving safe. Computer vision has played a crucialpart in design of these systems. With the introduction of vision techniques variousautonomous and robust real-time traffic automation systems have been designed such asTraffic monitoring, Traffic related parameter estimation and intelligent vehicles. Among theseautomatic detection and recognition of road signs has became an interesting research topic.The system can assist drivers about signs they don’t recognize before passing them.Aim of this research project is to present an Intelligent Road Sign Recognition System basedon state-of-the-art technique, the Support Vector Machine. The project is an extension to thework done at ITS research Platform at Dalarna University [25]. Focus of this research work ison the recognition of road signs under analysis. When classifying an image its location, sizeand orientation in the image plane are its irrelevant features and one way to get rid of thisambiguity is to extract those features which are invariant under the above mentionedtransformation. These invariant features are then used in Support Vector Machine forclassification. Support Vector Machine is a supervised learning machine that solves problemin higher dimension with the help of Kernel functions and is best know for classificationproblems.

Estimated lifetimes of road pavements in Sweden using time-to-event analysis

Maintenance planning of road pavement requires reliable estimates of roads’ lifetimes. In determining the lifetime of a road, this study combines maintenance activities and road condition measurements. The scope of the paper is to estimate lifetimes of road pavements in Sweden with time to event analysis. The model used includes effects of pavement type, road type, bearing capacity, road width, speed limit, stone size and climate zone, where the model is stratified according to traffic load. Among the nine analyzed pavement types, stone mastic had the longest expected lifetime, 32 percent longer than asphalt concrete. Among road types, ordinary roads with cable barriers had 30 percent shorter lifetime than ordinary roads. Increased speed lowered the lifetime, while increased stone size (up to 20 mm) and increased road width lengthened the lifetime. The results are of importance for life cycle cost analysis and road management.

Benchmark Evaluation of HOG Descriptors as Features for Classification of Traffic Signs

The purpose of this paper is to analyze the performance of the Histograms of Oriented Gradients (HOG) as descriptors for traffic signs recognition. The test dataset consists of speed limit traffic signs because of their high inter-class similarities.   HOG features of speed limit signs, which were extracted from different traffic scenes, were computed and a Gentle AdaBoost classifier was invoked to evaluate the different features. The performance of HOG was tested with a dataset consisting of 1727 Swedish speed signs images. Different numbers of HOG features per descriptor, ranging from 36 features up 396 features, were computed for each traffic sign in the benchmark testing. The results show that HOG features perform high classification rate as the Gentle AdaBoost classification rate was 99.42%, and they are suitable to real time traffic sign recognition. However, it is found that changing the number of orientation bins has insignificant effect on the classification rate. In addition to this, HOG descriptors are not robust with respect to sign orientation.

Review of the effectiveness of vehicle activated signs

This paper reviews the effectiveness of vehicle activated signs. Vehicle activated signs are being reportedly used in recent years to display dynamic information to road users on an individual basis in order to give a warning or inform about a specific event. Vehicle activated signs are triggered individually by vehicles when a certain criteria is met. An example of such criteria is to trigger a speed limit sign when the driver exceeds a pre-set threshold speed. The preset threshold is usually set to a constant value which is often equal, or relative, to the speed limit on a particular road segment. This review examines in detail the basis for the configuration of the existing sign types in previous studies and explores the relation between the configuration of the sign and their impact on driver behavior and sign efficiency. Most of previous studies showed that these signs have significant impact on driver behavior, traffic safety and traffic efficiency. In most cases the signs deployed have yielded reductions in mean speeds, in speed variation and in longer headways. However most experiments reported within the area were performed with the signs set to a certain static configuration within applicable conditions. Since some of the aforementioned factors are dynamic in nature, it is felt that the configurations of these signs were thus not carefully considered by previous researchers and there is no clear statement in the previous studies describing the relationship between the trigger value and its consequences under different conditions. Bearing in mind that different designs of vehicle activated signs can give a different impact under certain conditions of road, traffic and weather conditions the current work suggests that variable speed thresholds should be considered instead.

Triggering Solar-Powered Vehicle Activated Signs using Self Organising Maps with K-means

Solar-powered vehicle activated signs (VAS) are speed warning signs powered by batteries that are recharged by solar panels. These signs are more desirable than other active warning signs due to the low cost of installation and the minimal maintenance requirements. However, one problem that can affect a solar-powered VAS is the limited power capacity available to keep the sign operational. In order to be able to operate the sign more efficiently, it is proposed that the sign be appropriately triggered by taking into account the prevalent conditions. Triggering the sign depends on many factors such as the prevailing speed limit, road geometry, traffic behaviour, the weather and the number of hours of daylight. The main goal of this paper is therefore to develop an intelligent algorithm that would help optimize the trigger point to achieve the best compromise between speed reduction and power consumption. Data have been systematically collected whereby vehicle speed data were gathered whilst varying the value of the trigger speed threshold. A two stage algorithm is then utilized to extract the trigger speed value. Initially the algorithm employs a Self-Organising Map (SOM), to effectively visualize and explore the properties of the data that is then clustered in the second stage using K-means clustering method. Preliminary results achieved in the study indicate that using a SOM in conjunction with K-means method is found to perform well as opposed to direct clustering of the data by K-means alone. Using a SOM in the current case helped the algorithm determine the number of clusters in the data set, which is a frequent problem in data clustering.

Draft Proposed Public Transportation Routes for Waterville, ME

Currently, there is a public bus transportation route in Waterville, Maine. However, this system could be improved. Our goal was to use GIS to find optimal public transportation routes throughout the city based on given points of interest and high population density areas. Three different groups of points of interest were created in the North, West, and South sections of Waterville. Using the Network Analyst tool, which calculates optimal routes, using existing street data, based on the input of stops, barriers, and impedance, we ran an analysis of what we thought would be the routes that best served the greatest number of people. Two different sets of routes were found: one with length as the impedance (the shortest length between the selected stops was favored), and one with population density as the impedance (the roads with the highest population density were favored). Finally, the times of the resulting routes (given a constant speed limit of 25 mph) were calculated and evaluated.