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From manual to automatic pavement distress detection and classification

Detection and classification of distresses is a fundamental activity in the road pavement management. Even in the early stages of deterioration, road pavement needs to be monitored to identify problems, evaluating the actual conditions and predicting what the future conditions will be. Monitoring activities through manual/visual inspections are time consuming, costly and cause of safety concerns.

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The European Directive 2008/96/CE on Road Infrastructures Safety Management gives great emphasis to road Safety Inspections SI as tool for safety management of existing roads. In this framework, development of surrogate measures of safety derived from data collected during safety inspections can provide a source of information for risk assessment. Furthermore, SIs derived information seems to be p

Investigating the influence of passing relief lane sections on safety and traffic performance

As it is well known, one of the keys to improve traffic performance of two lane rural roads with high traffic volumes is to provide passing sections. However, providing a long segment in which the passing maneuver is allowed, is not always feasible, especially when suburban areas are considered. The retrofitting of some road sections by adding a passing relief lane can improve traffic performance

Investigating the influence on safety of retrofitting Italian motorways with barriers meeting a new EU standard

Objective: A new European Union (EU) regulation for safety barriers, which is based on performance, has encouraged road agencies to perform an upgrade of old barriers, with the expectation that there will be safety benefits at the retrofitted sites. The new class of barriers was designed and installed in compliance with the 1998 (European Norm) EN 1317 standards for road restraint systems, which l

Comparison of Italian and Hungarian Black Spot Ranking

Black spot ranking is an important tool for finding the sites with potential safety improvement on the road network. The EU Directive on Road Infrastructure Safety Management also demands the ranking of high accident concentration sites. This paper gives an introduction to localizing high accident concentration sites and the indicators used by Italy and Hungary. Accident and traffic volume data ar

The assessment of road safety for passing relief lanes using microsimulation and traffic conflict analysis

Most crash prediction models are statistically-based prediction methods which require significant efforts in crash data collection and may not be applied in particular traffic environments due to the limitation of data sources. Traffic conflict studies have been proposed to mitigate this issue using short time survey to count traffic conflicts which are assumed as a surrogate measure of safety. Un

Comparison of in situ devices for the assessment of pavement subgrade stiffness

The subgrade is the top surface of a roadbed upon which the pavement structure is constructed. The purpose is to provide a platform for construction of the pavement and to support the pavement without unwanted deflection that would reduce its performance. For those reasons subgrade bearing capacity have to be investigate during the construction process as a quality control, based on the design res

Assessing the stochastic variability of the Benefit-Cost ratio in roadway safety management

Road Agencies set quantitative targets and adopt related road safety strategies within the priorities and the available resources at the time of an economic crisis. In this framework, benefit-cost analyses (BCA) are carried out to support the decision making process and alternative measures are ranked according to their expected benefit and benefit-cost ratio calculated using a Safety Performance

Reliability-based assessment of benefits in roadway safety management

Road agencies set quantitative targets and adopt related road safety strategics in accordance with each agency's priorities and available resources. Benefit-cost analyses are carried out to support the decision-making process, and alternative measures are ranked according to their expected benefits and benefit-cost ratios, calculated with a safety performance function (SPF) and crash modification

Investigating transferability and goodness of fit of two different approaches of segmentation and model form for estimating safety performance of motorways

The analysis of a road network could be carried out using different techniques, the most advanced of which for the identification of hazardous sites are based on a statistical tool known as a "Safety Performance Function" (SPF). SPFs are fundamental to procedures in the Highway Safety Manual (HSM) and Safety Analyst, both of which require calibration of the SPFs to local conditions. In the case of

Dread and Risk Elimination Premium for the Value of a Statistical Life

The value of a statistical life (VSL) is a widely used measure for the value of mortality risk reduction. As VSL should reflect preferences and attitudes to risk, there are reasons to believe that it varies depending on the type of risk involved. It has been argued that cancer should be considered a "dread disease," which supports the use of a "cancer premium." The objective of this study is to in

DMAC: Deadline-Miss-Aware Control

The real-time implementation of periodic controllers requires solving a co-design problem, in which the choice of the controller sampling period is a crucial element. Classic design techniques limit the period exploration to safe values, that guarantee the correct execution of the controller alongside the remaining real-time load, i.e., ensuring that the controller worst-case response time does no

A functional agonist of insect olfactory receptors : Behavior, physiology and structure

Chemical signaling is ubiquitous and employs a variety of receptor types to detect the cacophony of molecules relevant for each living organism. Insects, our most diverse taxon, have evolved unique olfactory receptors with as little as 10% sequence identity between receptor types. We have identified a promiscuous volatile, 2-methyltetrahydro-3-furanone (coffee furanone), that elicits chemosensory

Ubiquitous neocortical decoding of tactile input patterns

Whereas functional localization historically has been a key concept in neuroscience, direct neuronal recordings show that input of a particular modality can be recorded well outside its primary receiving areas in the neocortex. Here, we wanted to explore if such spatially unbounded inputs potentially contain any information about the quality of the input received. We utilized a recently introduced

Traffic conflicts analyses for 2+1 road sections

The additional passing lanes and 2+1 roads improve significant road safety. Studies indicate sections with additional passing lanes (relief or alternately), which may cause reduction in the number of accidents by 50%. However, how geometric design affects the safety performance of such sections is not in depth investigated. Previous studies are carried out with two approaches, i.e. the most often,

Physiology, Metabolism, and Fossilization of Hot-Spring Filamentous Microbial Mats

The evolutionarily ancient Aquificales bacterium Sulfurihydrogenibium spp. dominates filamentous microbial mat communities in shallow, fast-flowing, and dysoxic hot-spring drainage systems around the world. In the present study, field observations of these fettuccini-like microbial mats at Mammoth Hot Springs in Yellowstone National Park are integrated with geology, geochemistry, hydrology, micros

Sperm count in Swedish clinical stage I testicular cancer patients following adjuvant treatment

BACKGROUND: Little is known regarding sperm production following adjuvant treatment in testicular cancer (TC) clinical stage I (CS I) patients. PATIENTS AND METHODS: A total of 182 TC patients aged 18-50 years were prospectively included during 2001-2006 at any given time within 5 years of orchiectomy. Semen samples were delivered postorchiectomy but before further treatment, 6, 12, 24, 36 and 60

A review and evaluation of circular business model innovation tools

The circular economy has been heralded as a potential driver for sustainable development by business, academia, and policymakers. In a future circular economy, new business models are needed that slow, close and narrow resource loops to address key resource and climate challenges. After a phase of excitement and inspiration, an operationalization phase needs to start to ensure the best possible im