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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>Investigation on mechanical and microwave heating characteristics of asphalt mastic using activated carbon powder as electro-magnetic absorbing materials</title>
      <link>https://trid.trb.org/View/2605941</link>
      <description><![CDATA[Activated carbon, one of carbon-based materials with developed pore structure and favourable microwave radiation absorption, was added in asphalt to investigate its possibility as microwave heating enhancement in asphalt materials. Effect of activated carbon powder (ACP) on mechanical performance of asphalt mastic was firstly studied. Mechanical tests including multiple stress creep and recovery (MSCR) test, temperature sweep test, time sweep test, and linear amplitude sweep (LAS) test were conducted to evaluate rutting resistance, liner viscosity, and fatigue resistance. Interactions between fillers and asphalt were then observed by scanning electron microscope (SEM). Besides, microwave heating capacity of asphalt mastic with different amount of ACP was investigated to ensure its potential in microwave heating acceleration. Cost of activated carbon powder in asphalt mixture was roughly estimated and compared with other microwave absorbing materials. Results showed that addition of ACP slightly influenced physical properties of mastic, permanent deformation at high temperature of asphalt mastic decreased and creep recovery increased. Increase of complex shear modulus and rutting factor suggested that asphalt was stiffened by adding ACP and rutting resistance was also improved. Fatigue resistance was improved and fatigue life was extended most when ACP replacement was 100% volume fraction of fillers. Wetting surface between ACP and asphalt was smooth with less folds and voids which means it had good contact and interaction with asphalt. Mastic with larger amount of ACP had a quick temperature rise under microwave radiation and heating rate (HR) defined as temperature increment per seconds was applied. It is found that surface temperature increased firstly fast and then slowly when dividing heating process as two stage. Results basically ensured the feasibility of ACP in enhancing mechanical performance and microwave heating capacity of asphalt materials. The extra cost from ACP is relatively lower. Partial substitution of ACP in fillers and reused ACP from pollution treatment factories may further reduce the amount and cost from ACP application.]]></description>
      <pubDate>Mon, 24 Nov 2025 10:23:28 GMT</pubDate>
      <guid>https://trid.trb.org/View/2605941</guid>
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    <item>
      <title>Assessment of Electromagnetic Exposure Levels for Humans from Electric Vehicle DC Charging Stations</title>
      <link>https://trid.trb.org/View/2611423</link>
      <description><![CDATA[The potential health risks of DC charging piles to human health were investigated by quantifying the internal electromagnetic exposure level. In this study, the transformer in the DC/DC circuit of a DC charging pile was selected as the radiation source, and two realistic human models (adult and child) were used as exposure subjects. A simulation model, including the vehicle body, charging pile, and transformer, was established using COMSOL(COMSOL Multiphysics 6.2) Multiphysics software to calculate the magnetic induction intensity (B-field) and electric field intensity (E-field) in various organs at distances of 0.1 m, 0.3 m, and 0.6 m from the charging pile. The results show that at 0.1 m, the peak B-field (1.91 microT) and E-field (447 mV/m) in the adult body were 1.91% and 2.07% of the ICNIRP occupational exposure limits, respectively, and 7.07% and 4.14% of the public exposure limits. For the child model, the peak electromagnetic exposure levels (2.31 microT and 259 mV/m) were only 8.56% and 2.40% of the public limits. Further evaluation of exposure levels for in-vehicle occupants during charging showed that the peak B-field and E-field for an adult driver and a child in the front passenger seat were 0.0225 x 10-2 microT, 0.0237 x 10-2 microT, 5.81 mV/m, and 5.82 mV/m, respectively, far below the ICNIRP public limits. Additionally, analyses at multiple frequency bands (85 kHz, 90 kHz, and 95 kHz) under a typical scenario (adult at 0.1 m from the charging pile) revealed that the B-field in the human body decreased with increasing frequency, while the E-field showed minimal variation due to shielding effects. All electromagnetic exposure levels were below both ICNIRP public and occupational limits, indicating the broad applicability of the results. Under normal operating conditions of DC charging piles, the electromagnetic exposure from the DC/DC transformer fully complies with safety standards and poses no threat to human health. This study provides a scientific basis for alleviating public concerns about the health risks of electromagnetic radiation from DC charging piles for electric vehicles.]]></description>
      <pubDate>Thu, 23 Oct 2025 09:22:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/2611423</guid>
    </item>
    <item>
      <title>A Polarization and Radiation Beam Reconfigurable Integrated Antenna With Broadband and High Gain for mmWave Vehicular Communication</title>
      <link>https://trid.trb.org/View/2582764</link>
      <description><![CDATA[A novel integrated antenna supporting polarization and radiation beam reconfigurability is proposed for emerging millimeter-wave (mmWave) vehicular communication. To meet the reconfigurability requirement of the vehicular communication system, a compact shared-aperture two-dimensional leaky-wave antenna (LWA) is designed. The LWA is generated by the parallel-plate waveguide (PPW) long-slot structure and its open stopband issue is suppressed completely by employing a unit cell with two asymmetrical slots, leading to high-gain and broadband characteristics. Besides, a multifunction feeding network constituted by four switchable input ports, four parabolic reflector systems, and an integrated multifunction coupler is seamlessly incorporated with the radiation aperture within a single substrate, realizing a low-cost solution for vehicular communication applications. Based on the proposed design concept, a broadband high-gain integrated antenna featuring polarization and radiation beam reconfigurability is engineered, fabricated, and installed into an antenna measurement system for validation. Experimental results demonstrate that the proposed antenna achieves a peak gain of 23.6 dBi together with a bandwidth of 56.6% from 19 GHz to 34 GHz. Additionally, it exhibits good polarization and radiation beam reconfigurable capability, providing horizontal/vertical linear-polarization single-beam, right-/left-handed circular-polarization single-beam, and dual-linear-polarization equal/unequal-amplitude dual-beam operating capability. Furthermore, a wide beam scanning coverage of 105 degrees in xoz-plane and 108 degrees in yoz-plane is achieved by the presented design. The extraordinary advantages of the proposed integrated antenna such as wide bandwidth, high gain, polarization and radiation beam reconfigurability, and low cost make it suitable for various millimeter-wave vehicular communication application scenarios.]]></description>
      <pubDate>Wed, 06 Aug 2025 15:01:59 GMT</pubDate>
      <guid>https://trid.trb.org/View/2582764</guid>
    </item>
    <item>
      <title>Analysis of Performance and Radiation Regulation Compliance for a Small Sub-Array Based Ka Band Antenna</title>
      <link>https://trid.trb.org/View/2512405</link>
      <description><![CDATA[The integration of non-terrestrial networks (NTN) and terrestrial networks, driven by the developments in 5G, 5G-advanced, and 6G, have resulted in an abundance of new and unique application scenarios for exploiting existing and upcoming satellite networks. With an increasing number of available satellites, there is a growing demand for user terminals to support NTN services, particularly for earth stations on mobile platforms (ESOMP). In order to allow usability of these user terminals on ESOMPs, low cost, small, and power-efficient antennas need to be developed. Moreover, regulatory issues must be taken into account, in order for the new terminals to be capable to interoperate and not interfere with existing systems. This paper investigates the radiation performance of small Ka band satcom antennas as well as their compliance with current European Telecommunications Standards Institute (ETSI) radiation regulations.]]></description>
      <pubDate>Thu, 01 May 2025 09:36:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/2512405</guid>
    </item>
    <item>
      <title>E-Argus: Drones Detection by Side-Channel Signatures via Electromagnetic Radiation</title>
      <link>https://trid.trb.org/View/2449348</link>
      <description><![CDATA[The increasing misuse of commercial drones for illicit activities poses significant challenges in their detection and identification. Existing methods, such as acoustic-based, radio frequency-based, and computer vision approaches, face limitations due to factors like miniaturization, stealth, and background noise. In this paper, the authors propose E-Argus, a system that leverages the electromagnetic radiation (EMR) emitted by the memory of drones. It is a basic fact that, with all types of drones, the implementation of arbitrary behavior must be digested in the built-in memory, and electromagnetic radiation is thus generated. Specifically, the memory clock drives the switching regulator causing current fluctuations that generate EMR signals at the clock frequency. E-Argus combines the relationship between the flight pattern of the drone and the memory EMR signal, analyzes the unique side-channel signatures, and utilizes advanced neural network-based identification; E-Argus can accurately detect and identify various types of illegal drones. They designed a system prototype based on USRP B210 and conducted experiments in a wide range of scenarios. The evaluation shows that E-Argus has low latency, high accuracy, and robustness in real environments.]]></description>
      <pubDate>Thu, 17 Apr 2025 16:55:18 GMT</pubDate>
      <guid>https://trid.trb.org/View/2449348</guid>
    </item>
    <item>
      <title>Ferrite Absorbers of Electromagnetic Radiation in Microwave Range</title>
      <link>https://trid.trb.org/View/2407731</link>
      <description><![CDATA[The study is devoted to the development of compositions and technology for applying a radio-absorbing ferrite-containing coating to the surface of corundum armored ceramics products to ensure radar protection of technical weapons. The results of a study of radio absorption in the microwave range of ferrite absorbers of various crystal-chemical nature are presented. The objects of study were the synthetic compositions of hexaferrites and ferrites of the spinel group, including industrially manufactured ferrites of the 6000NM1, 3000NMS, 2500NMS, and 600NN grades. The most technological in manufacturing and reproducibility of properties are barium, barium - zinc, lithium and nickel-zinc ferrites. In the frequency dependence (from 8 to 18 GHz) of absorption of electromagnetic radiation of various ferrites, blurred extremums are found. The characteristic frequency dependence of the radio-absorbing properties of the investigated types of fillers indicates a single mechanism for the absorption of electromagnetic radiation. The research results are interpreted from the standpoint of the structural type of ferrites, the nature of the material formed by the microstructure and electromagnetic parameters. It is shown that magnetically soft and magnetically hard ferrites in terms of their physicochemical nature, crystal-chemical type and electromagnetic parameters correspond to the greatest extent to the requirements for active fillers. To ensure broadband absorption of an electromagnetic signal, soft magnetic and hard magnetic ferrites in combination with carbonyl iron and discrete carbon fibers should be used as active absorbers.]]></description>
      <pubDate>Wed, 19 Mar 2025 10:12:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/2407731</guid>
    </item>
    <item>
      <title>Correlation of Automotive Electromagnetic Emissions Measurements</title>
      <link>https://trid.trb.org/View/1783194</link>
      <description><![CDATA[Although automotive electromagnetic emissions measurements are conventionally carried out at a range of 10 m under semi-anechoic conditions, some standards permit 3 m measurements to be used if a 10 dB adjustment is applied to the limit. Experimental and theoretical studies have been used to investigate this approach, and to assess whether data recorded in a fully anechoic environment can be used in this manner. This work indicates that measurements at 3 m can provide more accurate electric field data and that the effect of the ground plane is small at this range. These studies also suggest that a 5 dB adjustment may be more appropriate to estimate emissions levels at the 10 m range.]]></description>
      <pubDate>Sat, 07 Sep 2024 12:06:59 GMT</pubDate>
      <guid>https://trid.trb.org/View/1783194</guid>
    </item>
    <item>
      <title>Monitoring Model for Three-Way Catalyst Converter Efficiency Based on Exotherm</title>
      <link>https://trid.trb.org/View/2203830</link>
      <description><![CDATA[This paper analyzes the mass-transfer and diathermancy of the three-way catalytic converter (TWCC). Applying mass-conservation and energy-conservation for gas and solid, the paper establishes a TWCC inner equation and makes the model dimensionless. The numerical models between the conversion efficiency and outlet-inlet gas temperature difference of TWCC working at a stable condition are derived. Lastly, the verified experiment is processed and the reasons for the errors are explained. The results show that the models are useful.]]></description>
      <pubDate>Thu, 25 Jul 2024 17:12:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/2203830</guid>
    </item>
    <item>
      <title>Electromagnetic Radiation from High-Voltage Transmission Lines: Impact on UAV Flight Safety and Performance</title>
      <link>https://trid.trb.org/View/2317300</link>
      <description><![CDATA[Unmanned aerial vehicles (UAVs) have emerged as versatile tools across various sectors, including power distribution infrastructure. While UAVs offer significant advancements in the time and cost-effectiveness of energy distribution infrastructure inspections, such operations present several challenges. The main challenges include the risk of collision with transmission cables themselves and the high potential for electromagnetic interference caused by high-voltage power lines. This research investigates the strength of the electromagnetic field (EMF) emitted by high-voltage power lines while identifying potential concerns for UAVs operating nearby. The research team conducted a series of experiments to quantify the strength of magnetic, electric, and radiofrequency fields induced by power transmission lines. A thorough understanding of the magnitude and potential effects of EMF from power lines is of great importance when conducting UAV flights in their direct vicinity. This understanding is crucial not only for ensuring the safety of infrastructure inspection flights but also for the safety of all UAV flights carried out near high-voltage lines. Our study contributes to the body of knowledge concerning the influence of electromagnetic radiation from high-voltage transmission lines on UAVs, providing valuable insights into mitigating risks associated with UAV flights in critical infrastructure inspections, as well as other operations.]]></description>
      <pubDate>Fri, 29 Mar 2024 16:58:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2317300</guid>
    </item>
    <item>
      <title>Significant changes in cloud radiative effects over southwestern United States during the COVID-19 flight reduction period</title>
      <link>https://trid.trb.org/View/2293981</link>
      <description><![CDATA[Aircraft-induced clouds (AICs) are one of the most visible anthropogenic atmospheric phenomena, which mimic the natural cirrus clouds and perturb global radiation budget by reducing incoming shortwave (SW) radiation and trapping outgoing longwave (LW) radiation. The COVID-19 pandemic has caused a 70 % global decline in flight numbers from mid-March to October 2020, which provided a unique opportunity to examine the climatic impact of AICs. Among various regions, Western Europe and the Contiguous United States experienced the most substantial reduction in air traffic during the COVID-19 pandemic. Interestingly, only the Southwestern United States demonstrated a significant decrease in cirrus clouds, leading to notable changes in shortwave (SW) and longwave (LW) cloud radiative effects. Such changes were likely due to the reduction in AICs. However, further investigations indicated that this region also experienced abnormal high pressure and low relative humidity in the middle and upper atmosphere, resulting in unusual subsidence and dryness that prohibit the formation and maintenance of cirrus cloud. While it remains challenging to quantify the exact climatic impact of reduced AICs, the remarkable anomalies documented in this study provide valuable observational benchmark for future modelling studies of the climatic impact AICs.]]></description>
      <pubDate>Mon, 11 Dec 2023 08:58:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/2293981</guid>
    </item>
    <item>
      <title>Shared-Metasurface Antenna With Diverse Reflection, Radiation and Polarization Characteristics for Vehicular Communications</title>
      <link>https://trid.trb.org/View/2201080</link>
      <description><![CDATA[This paper presents a shared-metasurface antenna with frequency, directivity and polarization diversities for vehicular communications. The designed metasurface can be simultaneously used as the radiation source of a wideband metasurface antenna, the surface waveguide of a surface-wave antenna and the frequency selective surface (FSS) of a circularly-polarized (CP) array. By placing a printed dipole below the metasurface, the linearly-polarized (LP) broadside radiation in the frequency band of 3.65~4.58 GHz is realized. Besides, surface waves are excited and supported within the metasurface. Dual quasi-endfire patterns are then generated at two edges from 5.70 to 5.96 GHz due to the discontinuousness. In addition, the broadside CP radiation performance can be realized from 19.45 to 21.85 GHz by placing a CP array below the printed dipole. The designed antenna is simulated and measured. Measured results indicate that the proposed shared-metasurface antenna can be simultaneously applied to the vehicular terrestrial 5G, vehicle-to-everything (V2X) and vehicle-to-satellite (V2S) communications.]]></description>
      <pubDate>Tue, 27 Jun 2023 09:16:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/2201080</guid>
    </item>
    <item>
      <title>Compact Dual-Band Filtenna With Controllable Radiation Nulls for Vehicle Application</title>
      <link>https://trid.trb.org/View/2138498</link>
      <description><![CDATA[This paper presents a compact dual-band filtenna with controllable radiation nulls for Shark-Fin scenarios. The proposed filtenna is composed of three quarter-wavelength dual-band resonators. The resonator in the middle is fed by the probe. The other resonators on both sides of the middle resonator are coupled by the mixed electromagnetic (EM) field. Since the electric and magnetic couplings can be cancelled, the mixed EM coupling can be used to obtain more radiation nulls with less order than the other coupling mechanisms. Thus, the proposed antenna is straightforward and compact. Furthermore, the dual-band Quasi-elliptical responses are realized. Four radiation nulls are realized on both sides of two pass-bands, and the positions can be flexibly adjusted in dual bands. Without extra filtering circuits, high radiation efficiency can be achieved. To analyze and guide antenna design, the RLC equivalent circuit and extraction method are provided. For demonstration, the proposed filtenna is implement-ed. Radiation efficiency is about 64% and 83% within 2.4–2.5 GHz and 5.0–5.88 GHz, respectively. Moreover, the out-of-band suppression is over 20 dB. Compared with the traditional antenna, the in-band radiation performance of the proposed antenna is almost maintained, whereas out-of-band suppression is significantly enhanced. The proposed filtenna is suitable for Shark-Fin scenarios where multiple antennas operating at different frequency bands coexist. The interference from antennas at adjacent bands is reduced significantly due to the out-of-band suppression. Specially, the isolation between the proposed dual-band filtenna and antennas operating at the other bands can be improved by about 21 dB.]]></description>
      <pubDate>Thu, 23 Mar 2023 10:19:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/2138498</guid>
    </item>
    <item>
      <title>Micro-pressure wave radiation from tunnel portals in deep cuttings</title>
      <link>https://trid.trb.org/View/2100394</link>
      <description><![CDATA[The reflection and radiation of steep-fronted wavefronts at a tunnel exit to a deep cutting is studied and contrasted with the more usual case of radiation from over-ground portals. A well-known difference between radiation in odd and even dimensions is shown to have a significant influence on reflected wavefronts, notably causing increased distortion that complicates analyses, but that can have practical advantages when rapid changes are undesirable. Likewise, micro-pressure waves (MPWs) radiating from the portal into a cutting are shown to exhibit strong dispersion that does not occur in the corresponding radiation into an open terrain. In the latter case, formulae that represent the behaviour of monopoles and dipoles are commonly used to estimate conditions beyond tunnel portals, but no such simple formula exists (or is even possible) for cylindrical radiation that is characteristic of MPWs in cuttings. An important outcome of the paper is the development of an approximate relationship that predicts the maximum amplitudes of these MPWs with an accuracy that should be acceptable in engineering design, at least for initial purposes. The formula shows that peak pressure amplitudes decay much more slowly than those from an overground portal, namely varying approximately as r−⁰.⁵ compared with r−¹, where r denotes the distance from the portal.]]></description>
      <pubDate>Mon, 13 Mar 2023 10:23:38 GMT</pubDate>
      <guid>https://trid.trb.org/View/2100394</guid>
    </item>
    <item>
      <title>Time domain potential and source methods and their application to twin-hull high-speed crafts</title>
      <link>https://trid.trb.org/View/2107911</link>
      <description><![CDATA[The numerical accuracy of time dependent potential and source methods is compared against analytical and other numerical results using an in-house transient wave-body interaction three-dimensional wave Green function computational tool of ITU-WAVE. The time dependent Impulse Response Functions (IRFs) are used to predict the behaviour of radiation forces, exciting forces, and response of floating bodies. For radiation force IRFs, the numerical results show that potential method converges with less numbers of panels compared to source method, while in the case of diffraction force IRFs, the convergence is achieved with the same number of elements for both potential and source methods. As potential method achieves convergence faster than source method for radiation force IRFs prediction, potential method is applied for the hydrodynamic and response parameters of a twin-hull high-speed craft. The present ITU-WAVE numerical results, which are compared with experimental, analytical, and other numerical results for validation purposes show satisfactory agreements.]]></description>
      <pubDate>Mon, 27 Feb 2023 08:51:34 GMT</pubDate>
      <guid>https://trid.trb.org/View/2107911</guid>
    </item>
    <item>
      <title>A Fast Prediction Approach of Radiated Emissions From Closely-Spaced Bent Cables in Motor Driving System</title>
      <link>https://trid.trb.org/View/1987492</link>
      <description><![CDATA[Three-phase cables in a motor driving system are the major ways of electromagnetic radiation, which result in potential interference to the nearby electronic equipment on electric vehicle. Numerical simulation of radiated emissions from cables is time-consuming, which becomes insufficient to compute large numbers of cables for actual applications. Hence, this article proposes a fast prediction approach that can highly improve the computational efficiency. Since cables are often close to each other and arbitrarily bent in the real application due to confined working space, the influence of proximity effects caused by closely-spaced cables on radiated emissions is also considered in the calculation model by multi-transmission line and Hertzian dipole theories. Besides, an equivalent model is presented to characterize the measured motor impedance. On the basis of the proposed cables model, a complete motor driving system model is originally developed by integrating a radiated electromagnetic interference (EMI) source model of inverter and a load equivalent model of motor impedance. The system model is of vital value to identify the mechanism concerning radiated EMI issues on electric vehicles and efficiently evaluated in the end. Both numerical simulations and experiments are conducted for the validation of proposed approach, which show that the proposed approach can save over 90% computational time with desired evaluation accuracy.]]></description>
      <pubDate>Thu, 21 Jul 2022 11:42:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/1987492</guid>
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