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    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <language>en-us</language>
    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
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    <item>
      <title>Unsupervised pavement anomaly detection via conditional diffusion model and domain adaptive feature selection</title>
      <link>https://trid.trb.org/View/2628265</link>
      <description><![CDATA[Pavement defects pose serious threats to road safety and infrastructure longevity. Following a full-supervised manner, many existing detection methods rely heavily on extensive labeled data. In this paper, motivated by the inherent diversity and imbalance of real-world pavement images, we propose a reconstruction-based unsupervised pavement anomaly detection framework. It leverages a conditional guided blurring diffusion model to reconstruct abnormal images as defect-free, combined with domain-adaptive feature refinement and a defect-aware feature selection module for robust anomaly scoring. By integrating simplex noise within the conditional guiding framework, our approach effectively preserves normal pavement textures while removing defects, enabling precise localization without relying on pixel-level annotations. Extensive comparison and ablation experiments on the Pavementscape dataset demonstrate that our method outperforms other unsupervised anomaly detection techniques and remains competitive with fully supervised segmentation approaches. These results underscore the potential of our unsupervised, diffusion-driven pipeline to address the costly annotation bottleneck in large-scale pavement inspection, offering a scalable and highly accurate solution for real-world road maintenance.]]></description>
      <pubDate>Tue, 20 Jan 2026 09:09:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/2628265</guid>
    </item>
    <item>
      <title>An investigation of the asphalt blending during recycling using the analytical solutions of the binder diffusion models</title>
      <link>https://trid.trb.org/View/2548850</link>
      <description><![CDATA[Diffusion occurs during the blending process of asphalt recycling. The coefficient of diffusion between any two diffusing materials in asphalt recycling is estimated as a constant value, which is found to vary in the order of 10⁻⁹–10⁻¹⁶ $ {𝓂²}/𝒔 in past studies. In this study, Fick’s law of diffusion is solved analytically and modelled to simulate asphalt binder diffusion. A comparative study is performed among the models used to study the variability in asphalt binder diffusion. It is observed that the binder concentration gradients are inconsistent with similar initial and parametric values with the change in the boundary conditions adopted in the binder diffusion models. Similarly, the coefficient of diffusion predicted by the models varies for the models adopted under a constant time. From a comparative study of the models, it is observed that the complete blending condition may not be achieved in some cases.]]></description>
      <pubDate>Thu, 26 Jun 2025 11:42:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/2548850</guid>
    </item>
    <item>
      <title>Enhancing Rare Object Detection on Roadways Through Conditional Diffusion Models for Data Augmentation</title>
      <link>https://trid.trb.org/View/2449351</link>
      <description><![CDATA[The detection of rare objects within traffic environments is critically important for the safety and reliability of autonomous driving systems. However, the scarcity of sufficient data and the long-tail effect associated with rare objects pose significant challenges to their detection. To address this issue, this study introduces a Conditional Diffusion Model, the RareGenDiffuse Model, which generates images of rare objects by taking traffic background images and corresponding bounding box images as inputs. Based on diffusion models, the RareGenDiffuse Model enables control over the category and location of the generated rare objects by adjusting the bounding box images. Experimental results demonstrate that the proposed model offers the advantages of high clarity and controllability. Utilizing the generated rare object dataset significantly enhances the detection outcomes for rare objects. The methodology proposed in this study can effectively reduce the efforts required for data acquisition and labeling, presenting a valuable solution to the challenges of rare object detection in traffic scenarios.]]></description>
      <pubDate>Thu, 17 Apr 2025 16:55:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/2449351</guid>
    </item>
    <item>
      <title>Orientation of a diffuse reflector for improved coverage in ID-FSOC for vehicular communications</title>
      <link>https://trid.trb.org/View/1982117</link>
      <description><![CDATA[Even with no line-of-sight (LoS), stations can optically communicate using Indirect line-of-sight diffused-light free-space optical communications (ID-FSOC). A diffuse reflector in the LoS of the stations reflects diffused light to them. But despite having diffused reflections in almost all directions, the orientation of a flat diffuse reflector defines the communications coverage. Therefore, there is a need for a tool that describes the relationship between the orientation of the diffuse reflector, the coverage, and the achievable data rates for the effective deployment of ID-FSOC. In this paper, the authors propose a model of the coverage of a diffuse reflector that can allow us to estimate the achievable data rates as a product of the orientation of the diffuse reflector. They use ground-to-vehicle communications as a demanding example scenario. They also propose RISE, a heuristic algorithm that optimizes the horizontal and vertical tilt angles of the reflector to maximize the achievable data rates. They show that 50% or more of the transmitted power of light is reflected, thereby achieving 1 Gbps or higher data rates across the optical local area network.]]></description>
      <pubDate>Wed, 24 Aug 2022 15:02:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/1982117</guid>
    </item>
    <item>
      <title>Implications and outcomes of controlling a LED AFS (Adaptive Front-Lighting System) using fuzzy logic for the South American Markets</title>
      <link>https://trid.trb.org/View/1819376</link>
      <description><![CDATA[The vehicular illumination system has had, in the past decades, huge technological advances such as the use of a light emitting diode (LED) adaptive front-lighting system (AFS), which represents an industry breakthrough in lighting technology and is rapidly becoming one of the most important innovative technologies around the world in the lighting community. This paper presents AFS control alternatives using fuzzy logic (type 1 or 2) to determine its operating parameters taking into consideration both the driver's and road conditions from the state of Sao Paulo (Brazil). Fuzzy logic is a well-known extension of the conventional (Boolean) logic that enables the treatment of uncertainty presented in the information, through the definition of intermediary membership values between the “completely true” and the “completely false”. This technique or modeling strategy is particularly important when a multi-parameter decision must be taken or the decisions are based on the human knowledge. The results show the potentiality of the methodology proposed and its suitability for the add light control, providing night time driving safer according to the driver's and market needs.]]></description>
      <pubDate>Thu, 30 Jun 2022 15:05:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/1819376</guid>
    </item>
    <item>
      <title>Car Wake Flows and Ultrafine Particle Dispersion: From Experiments to Modelling</title>
      <link>https://trid.trb.org/View/1899503</link>
      <description><![CDATA[Improving air quality in urban environments and transportation systems is crucial. Concerns are related to health and environmental issues associated with huge costs. Car cabin is a microenvironment where pollutants can accumulate with possible risks for occupants. In automotive engineering, it has then become mandatory to study the path and dispersion of such pollutants emitted from the tailpipe of a car. In the present paper, the relation between the flow topology and the dispersion of ultrafine particles (UFP) in the wake of a vehicle is discussed. Experiments were undertaken at a reduced scale using simplified car models. Experimental conditions were defined to be representative of a vehicle in an urban environment. Based on experimental data, a simplified analytical model is developed, which aims at describing the concentration fields of UFP in the wake of a single vehicle for different rear slant angles. The strengths and limits of the present model are discussed and ways of improvements are suggested. Additional experiments are presented to assess the influence of the inter-vehicle distance on this recirculation region. Critical inter-vehicle distances were determined based on defined criteria for different rear slant angles of the leading vehicle and compared to safety clearances.]]></description>
      <pubDate>Tue, 21 Dec 2021 16:47:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/1899503</guid>
    </item>
    <item>
      <title>Dispersion of ultrafine particles in the wake of car models: a wind tunnel study</title>
      <link>https://trid.trb.org/View/1899472</link>
      <description><![CDATA[Worldwide around 7 million annual deaths are due to air pollution. Among all pollutants, Ultrafine Particles (UFP) cause strong adverse effects. In this paper, the dispersion of UFP is studied in the wake of car models characterized by different rear slant angles (?). Velocities and UFP concentrations are collected in a wind tunnel. The influence of the flow topology on the dispersion of these UFP is discussed. The results indicate that its structure strongly influences their dispersion. Whatever the rear slant angle is, the size of the recirculation region is a key parameter governing the dispersion of these UFP. For ? ?= ?0°, the flow is almost symmetric and concentration levels are higher and homogeneous in the close wake. The recirculation region is the largest one. The dispersion is enhanced in both horizontal and spanwise directions. For ? ?= ?25°, the flow is attached on the rear slant leading to a strong downwash effect. The volume of the recirculation region is the smallest. Longitudinal vortices develop from the edges of car model entrapping particles. Particle Number Concentration field is no more symmetric. For ? ?= ?35°, results are almost similar to those obtained for ? ?= ?0°. Comparisons with previous studies are discussed and possible applications are suggested.]]></description>
      <pubDate>Tue, 21 Dec 2021 16:45:04 GMT</pubDate>
      <guid>https://trid.trb.org/View/1899472</guid>
    </item>
    <item>
      <title>Removing Outliers from 3D Macrotexture Data by Controlling False Discovery Rate</title>
      <link>https://trid.trb.org/View/1601641</link>
      <description><![CDATA[Measurement of pavement macrotexture by noncontacting means is often contaminated by erroneous readings made by the instrument. These errors can be caused by extreme diffusion or refraction of the light source by aggregate or bitumen and are manifest in the data as outliers in both the positive and negative directions. In three dimensions, these errors can manifest themselves along the width and length of the measured profile as singularities or packets of continuous data. The problem is confounded by the constantly changing nature of pavement surfaces and large quantity of data gathered in three-dimensional (3D) applications. The identification and treatment of outliers proposed in this work is a new method that effectively treats outliers while continuously adapting to the surface measured. This is done by controlling the rate of false discoveries (measurements incorrectly identified as outliers) without affecting adjacent, correct, measurements.]]></description>
      <pubDate>Tue, 04 Jun 2019 09:41:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/1601641</guid>
    </item>
    <item>
      <title>Laermschutz: effektiv aber unauffaellig - wirksame Massnahmen brauchen keine hohen Mauern</title>
      <link>https://trid.trb.org/View/1491996</link>
      <description><![CDATA[Den mit dem Bahnbetrieb verbundenen Schallemissionen laesst sich mit einigen Massnahmen begegnen. Hohe Laermschutzwaende aber sind heute keineswegs mehr erste Wahl, inzwischen gibt es bessere, umgebungsvertraeglichere Loesungen. Die beim Rad-Schiene-Kontakt entstehenden Schallwellen und Vibrationen lassen sich direkt an der Schiene bekaempfen. Weitere neue Laermschutzloesungen dicht neben dem Gleis, gefertigt aus Gummi- oder Polymermischungen, sind niedrig, fuegen sich in die Umgebung sehr gut ein und sind wirkungsvoll. (A) ABSTRACT IN ENGLISH: Sound emission caused by rail operation is to handle effectively with several measures. Today, however, high noise barriers are not the first choice as there are better and more ambient compatible solutions. Sound waves and vibrations occurring by wheel-rail contact can be controlled directly on the rail itself. Some further new sound protection solutions which are situated close beside the tracks are made of rubber or polymer compounds. The construction is low, effective and fit in the environment very well.]]></description>
      <pubDate>Mon, 29 Jan 2018 09:48:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/1491996</guid>
    </item>
    <item>
      <title>Classification of rainfall radar images using the scattering transform</title>
      <link>https://trid.trb.org/View/1460371</link>
      <description><![CDATA[The main objective of this paper is to classify rainfall radar  images by using the scattering transform, which gives us  a translation invariant representation of the images and preserves  high-frequency information useful to encode important  morphological aspects of the meteorological phenomena under  study. To demonstrate the usefulness of the approach,  a classification framework is considered, where the images  are to be classified into 4 morphological classes: light rain,  shower, unorganised storm and organised storm. Experiments  show that the benefits of the scattering are threefold:  1) it provides complementary information with respect to  more traditional features computed over the distribution of  the rainfall intensities, 2) it provides strong invariance to  deformations, 3) second order coefficients of the scattering  transform nicely encodes spatial distribution of rain intensity]]></description>
      <pubDate>Fri, 17 Mar 2017 10:40:42 GMT</pubDate>
      <guid>https://trid.trb.org/View/1460371</guid>
    </item>
    <item>
      <title>Reclaimed Asphalt Pavement - Virgin Binder Diffusion in Asphalt Mixes</title>
      <link>https://trid.trb.org/View/1399572</link>
      <description><![CDATA[An importatnt factor when Reclaimed Asphalt Pavement (RAP) is considered for new hot mix asphalt is the blending between RAP and virgin binders to ensure pavement resistance to moisture damage, permanent deformation, and cracking.  It is shown that RAP-virgin binder diffusion in RAP mixes follows the same scientific concept as observed previously for extracted RAP-virgin binder diffusion alone.  The diffusion takes considerable amount of time even at elevated temperature.  Nevertheless, virtually all RAP binder can be homogenized with virgin binder.  A simulation of diffusion during realistic mix production, storage, and paving temperatures was performed.  It was demonstrated that binder diffusion may not be completed by the time the pavement constuction is completed.  Low extent of blending between RAP and virgin binder can result in lower mix stiffness when compared to that expected based on blending charts in AASHTO M 323.  Prolonged silo storage at elevated temperature can assist binder blending, however mix hardening due to binder oxidation, evaporation and aggregate absorption can be significant.  The outcomes of the study are based on laboratory testing of small mix specimens.  Due to high variability of testing, the conclusions from this study should be verified for variety of mix designs and eventually by a field study.]]></description>
      <pubDate>Fri, 26 Feb 2016 10:41:40 GMT</pubDate>
      <guid>https://trid.trb.org/View/1399572</guid>
    </item>
    <item>
      <title>Einfluss der Absorption von Laermschutzwaenden auf die Schallbeugung</title>
      <link>https://trid.trb.org/View/1359072</link>
      <description><![CDATA[Der Einfluss der absorbierenden Bekleidung von Laermschutzwaenden (LSW) auf das Abschirmmass wird numerisch und experimentell untersucht. In den RLS-90 (Richtlinien fuer den Laermschutz an Strassen) werden derartige Schall absorbierende Bekleidungen nicht beruecksichtigt. Fuer die numerischen Simulationen wird das Randelementeverfahren (BEM) verwendet, da mit dieser Methode Brechungs- und Beugungseffekte an Hindernissen wie LSW mit vorgegebenen absorbierenden Impedanzrandbedingungen berechnet werden koennen. Zuerst wird das zweidimensionale Problem untersucht, bei dem eine Linienquelle vor einer unendlich langen, geraden, reflektierenden und Schall absorbierenden LSW ueber schallhartem Boden betrachtet wird. Die Simulationen zeigen, dass in der unmittelbaren Naehe hinter der LSW die Wirkung der absorbierenden Bekleidung besonders ausgepraegt ist. Um das dreidimensionale Schallfeld einer Punktquelle vor reflektierenden und Schall absorbierenden LSW zu simulieren, wird - wie beim zweidimensionalen Problem - ebenfalls eine Halbraum-BEM angewendet, bei der der Boden als schallhart angenommen wird. Zur messtechnischen Validierung dieser Simulationsrechnungen werden Messungen an einer LSW unter Laborbedingungen im reflexionsarmen Raum durchgefuehrt und mit den Berechnungen der 3-D-BEM verglichen. Die zugehoerigen Einzahlwerte werden bestimmt. Sowohl die Mess- als auch die Rechenergebnisse zeigen, dass nur die quellseitige und die beidseitige Bekleidung mit Absorptionsmaterial nennenswerte Auswirkungen auf das Abschirmmass haben. Die BEM-Berechnungen liefern dann eine Erhoehung des Abschirmmasses um im Mittel 1-3 Dezibel (dB(A)) unter der Bedingung, dass sich der Messpunkt nicht oberhalb der Kante der LSW befindet.]]></description>
      <pubDate>Thu, 25 Jun 2015 08:55:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/1359072</guid>
    </item>
    <item>
      <title>Influence of moisture content on chloride diffusion in concrete</title>
      <link>https://trid.trb.org/View/1314908</link>
      <description><![CDATA[Chloride penetration into the cover of reinforced concrete is often at the origin of early damage due to corrosion of the steel reinforcement. The penetration rate of chloride, however, depends strongly of the water content. If diffusion coefficients as measured on saturated concrete are used for the prediction of service life by means of Fick's second law, chloride penetration may be overestimated. The mobility of chloride in concrete in hygral equilibrium with different relative humidity of the surrounding air was determined experimentally. Chloride mobility in concrete, which is in equilibrium with 50 % RH, is very low. This has to be taken into consideration in realistic service life prediction. (A)]]></description>
      <pubDate>Thu, 03 Jul 2014 15:24:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/1314908</guid>
    </item>
    <item>
      <title>FE² Method for Coupled Transient Diffusion Phenomena in Concrete</title>
      <link>https://trid.trb.org/View/1313201</link>
      <description><![CDATA[A coupled finite-element squared (FE²)-framework is formulated and employed for simulation of a transient and coupled moisture-chloride ion diffusion problem in concrete. Simulations are carried out on the macroscale, where the material response is obtained concurrently in the computations by introducing a representative volume element (RVE) in the macroscale quadrature points. The RVE, in turn, contains the mesoscale heterogeneities of concrete in terms of cement paste, aggregates, and interfacial transition zone (ITZ). In this fashion, the RVE comes to serve as a constitutive model for the macroscale. A numerical example is given to show how the transient macroscale diffusion is influenced by the composition of the mesoscale constituents. Parametric studies were carried out with respect to the aggregate content within the RVE, both including and excluding the ITZ, and the coupling parameters of moisture and chloride ions.]]></description>
      <pubDate>Mon, 30 Jun 2014 09:44:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/1313201</guid>
    </item>
    <item>
      <title>Evaluation of Moisture Sorption and Diffusion Characteristics of Asphalt Mastics Using Manual and Automated Gravimetric Sorption Techniques</title>
      <link>https://trid.trb.org/View/1308682</link>
      <description><![CDATA[One of the most important factors influencing the durability of asphalt mixtures is moisture-induced damage resulting from the presence and the transport of moisture in pavements. Moisture-induced damage is an extremely complicated phenomenon that is not completely understood but believed to be governed by the interaction of moisture with asphalt mix components (mastic and aggregates). The objective of this study was, therefore, to characterize the sorption and diffusion characteristics of asphalt mastic using gravimetric vapor sorption techniques. Moisture transport, in the hygroscopic region, in asphalt mastics was studied using both static and dynamic gravimetric vapor sorption techniques to determine equilibrium moisture uptake and diffusion coefficients as a function of aggregate and filler types. For the 25-mm diameter thin asphalt mastic films and the testing conditions (23°C and 85% relative humidity) considered, the kinetics of moisture uptake obtained were characteristic of Fickian diffusion with a concentration-dependent diffusion coefficient. Equilibrium moisture uptake and diffusion coefficient estimated from the static measurements were comparable and of the same order of magnitude as those from dynamic sorption techniques. Both measurement techniques ranked the mixes similarly, which suggest either method could be used to characterize moisture transport in asphalt mastics. Equilibrium moisture uptake was relatively higher in mixtures containing granite aggregates compared with limestone aggregate. In contrast, the diffusion coefficient of limestone aggregate mastics was higher than granite. Thus, an inversely proportional relationship exists between moisture uptake and diffusivity of the asphalt mastics studied. The results suggest moisture transport is a function of aggregate type and that both equilibrium moisture uptake and diffusion coefficient are useful in studying moisture susceptibility in asphalt mixtures. The effect of mineral filler type on diffusion coefficient was minimal in the mastics containing granite aggregate but relatively high in mastic samples containing limestone aggregates. Diffusion coefficient was found to increase with sample thickness, which was unexpected because diffusion coefficient (in an isotropic material) is considered an intrinsic property that is independent of sample size. The results suggested anisotropic diffusivity can occur in asphalt mastics and could be attributed to factors, including mineralogy, microstructure, air voids, and the tendency of the aggregates to settle at the bottom of asphalt mastic with time. In addition to characterizing moisture transport in asphalt mastics, the results presented in this paper will be useful as inputs for numerical simulation of moisture damage in asphalt mixtures.]]></description>
      <pubDate>Wed, 28 May 2014 15:21:17 GMT</pubDate>
      <guid>https://trid.trb.org/View/1308682</guid>
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