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Given anticipated climate change and its inherent uncertainty, a pavement could be subjected to different climatic conditions over its life and might be inadequate to withstand future environmental stresses beyond those currently considered during pavement design. This paper incorporates climate change effects into the mechanistic-empirical (M-E) based pavement design to explore potential climate change and its uncertainty on pavement design and performance. Three important questions are addressed: (1) How does pavement performance deteriorate differently with climate change and its uncertainty? (2) What is the risk if climate change and its uncertainty are not considered in design? and (3) How do pavement designers respond and incorporate this change into M-E design? Three test sites in the United States are examined and results demonstrate a robust and effective approach to integrate climate change into pavement design as an adaptation strategy. Key words: climate change, mechanistic-empirical based pavement design, uncertainty, pavement performance. Une chaussee pourrait etre soumise a differentes conditions climatiques durant sa vie en raison des changements climatiques anticipes et son incertitude inherente et pourrait etre inadequate pour resister aux futures contraintes environnementales superieures a celles considerees actuellement durant la conception de la chaussee. Cet article incorpore les effets du changement climatique dans la conception de chaussee mecanistique-empirique (M-E) afin d'explorer le changement climatique potentiel et son incertitude sur la conception et le rendement des chaussees. Trois questions importantes sont abordees: (1) comment se deteriore le rendement de la chaussee par rapport au changement climatique et son incertitude? (2) quel est le risque si un changement climatique et son incertitude ne sont pas consideres lors de la conception? et (3) comment les ingenieurs d'etude des chaussees repondent a ce changement et l'incorpore dans la conception M-E? Trois sites d'essais aux Etats-Unis sont examines et les resultats montrent une approche robuste et efficace d'integration du changement climatique dans la conception des chaussees en tant que strategie d'adaptation. [Traduit par la Redaction] Mots-cles: changement climatique, conception de chaussees mecanistique-empirique, incertitude, rendement des chausses., Introduction Pavement structures represent a significant infrastructure investment that is critical to the well-being, growth and expansion of any geographic location. As such pavements are expected to be durable and [...]

This paper presents a new approach to rough set theory in pavement rehabilitation and maintenance decision support systems. A rough set-based analysis acts like a knowledge engineer who sits between data and the user. The rough set concept is an effective tool for analysis of information systems in a pavement management system (PMS) database gained by both objective and subjective methods. The rough set approach in a PMS database enables pavement engineers to discover minimal subsets of condition attributes in assessing and describing the pavement conditions, and to derive decision rules in rehabilitation and maintenance decision making. The approach appears to capture information on uncertainty, imprecision, and ambiguity along with precise values in a PMS database.

Railroads have long used track inspection vehicles that capture data on a defined interval as the vehicle travels longitudinally down the track. These data can be captured on a constant interval, near-constant interval, or temporally. The data are normally evaluated in real time against exception thresholds, which define locations of safety or maintenance concern. In addition, railways evaluate multiple inspection runs of the same track over time to determine the rates of degradation. Since most inspection vehicles rely on the operator input of location events (mile posts, signals, switches, etc.) and tachometer-based distance measurement, the resulting inspection data are often longitudinally misaligned, on occasion by as much as several hundred feet. This paper presents an application of classical and advanced time-series methods for aligning data longitudinally. It also presents a novel methodology for aligning data with a nonconstant sampling interval, utilizing a combination of classical techniques. [ABSTRACT FROM AUTHOR]

Byline: Y.O. Adu-Gyamfi, Nii O. Attoh-Okine, A.Y. Ayenu-Prah Pavement profile analysis is a major component in pavement infrastructure management decision making for maintenance and rehabilitation. Road profile data are non-stationary and inherently non-Gaussian. This paper presents the application ensemble empirical mode decomposition (EEMD) to profile data analysis. The EEMD employs multiple applications of empirical mode decomposition (EMD), to which white noise is added, with constant amplitude relative to the target data. The uniform distribution of white noise over the entire time frequency space provides a reference frame for signals of comparative scale to collate in one intrinsic mode function, thus eliminating mode mixing. The EEMD approach was compared with the traditional EMD and it appears that the EEMD outperforms the traditional EMD.

Byline: Juel S. Gibbons, Nii O. Attoh-Okine, Shonali Laha The value of revitalising contaminated or brownfield sites has gained widespread acceptance. The efforts at remediation and eventual redevelopment of these sites involve several stakeholders, because the exercise directly impacts a number of different interests. The key issues to be resolved for the successful rejuvenation of brownfields are technical, legal, financial, future land use and community issues. Satisfactory resolution of these issues results in a happy confluence of interests working together to ensure the full exploitation of these underused assets. This paper fully discusses the issues and the attendant obstacles to redevelopment of brownfield sites, and examines some of the more successful approaches that have been employed.

The decision making in brownfield infrastructure necessitates the consideration of a multiplicity of complex, interrelated issues. However, technical issues, liability issues, financial issues, community concerns, and future land-use concerns are used to construct a hierarchical network for redevelopment decision-making. Finally, the Dempster-Shafer theory of combination is used to combine independent evidence from various issues to determine the overall uncertainty in redevelopment decision making.