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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=PHNlYXJjaD48cGFyYW1zPjxwYXJhbSBuYW1lPSJkYXRlaW4iIHZhbHVlPSJhbGwiIC8+PHBhcmFtIG5hbWU9InN1YmplY3Rsb2dpYyIgdmFsdWU9Im9yIiAvPjxwYXJhbSBuYW1lPSJ0ZXJtc2xvZ2ljIiB2YWx1ZT0ib3IiIC8+PHBhcmFtIG5hbWU9ImxvY2F0aW9uIiB2YWx1ZT0iMCIgLz48L3BhcmFtcz48ZmlsdGVycz48ZmlsdGVyIGZpZWxkPSJpbmRleHRlcm1zIiB2YWx1ZT0iJnF1b3Q7QW1wbGl0dWRlIG1vZHVsYXRpb24mcXVvdDsiIG9yaWdpbmFsX3ZhbHVlPSImcXVvdDtBbXBsaXR1ZGUgbW9kdWxhdGlvbiZxdW90OyIgLz48L2ZpbHRlcnM+PHJhbmdlcyAvPjxzb3J0cz48c29ydCBmaWVsZD0icHVibGlzaGVkIiBvcmRlcj0iZGVzYyIgLz48L3NvcnRzPjxwZXJzaXN0cz48cGVyc2lzdCBuYW1lPSJyYW5nZXR5cGUiIHZhbHVlPSJwdWJsaXNoZWRkYXRlIiAvPjwvcGVyc2lzdHM+PC9zZWFyY2g+" rel="self" type="application/rss+xml" />
    <description></description>
    <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>
    </image>
    <item>
      <title>Zero-Sequence High-Frequency Voltage Injection-Based Sensorless Method for Open-Winding-PMSM Drives With Common DC Bus</title>
      <link>https://trid.trb.org/View/2665522</link>
      <description><![CDATA[This article proposes a sensorless method for open-winding (OW)-permanent magnet synchronous machine (PMSM) drives with common dc bus utilizing zero-sequence (ZS) high-frequency (HF) voltage injection. The injection pattern is implemented with the ZS steerable space vector pulsewidth modulation. The three phase HF currents are amplitude-modulated by the rotor saliency. The rotor position can be extracted via a position observer with concise demodulation process. Different from other HF injection-based sensorless methods relating to the ZS, the proposed method no longer needs to build the ZS path deliberately. When compared with the classical HF voltage injection-based methods, owing to the separation of the injection voltage and the field-oriented control output voltage, the proposed method exhibits lower loss, vibration, and acoustic noise. Finally, the effectiveness of the proposed sensorless method is verified by experiments on a 12-slot/10-pole OW-PMSM drive platform.]]></description>
      <pubDate>Mon, 01 Jun 2026 09:13:31 GMT</pubDate>
      <guid>https://trid.trb.org/View/2665522</guid>
    </item>
    <item>
      <title>Scaling, Matching, and Variability: Effects of Ground Motion Selection in Performance Uncertainty</title>
      <link>https://trid.trb.org/View/2668494</link>
      <description><![CDATA[The selection of ground motions for time series analysis of structures remains a topic of considerable debate. While both time domain method and spectral matching are permitted by the Caltrans Seismic Design Criteria (SDC), the implications of the choice are not fully understood. To explore and compare how these different modification methodologies affect the estimation of means and distributions of bridge response parameters, two highway bridges in California were analyzed using suites of scaled and spectrally matched motions developed in accordance with Caltrans SDC. Hazard curves for engineering demand parameters (EDPs) are also developed using conditional scenario spectra (CSS) framework for each bridge to be used as a metric to evaluate the results. The results demonstrate that the spectral matching methodology consistently yields lower bias and variability in EDP predictions compared to amplitude scaling for both bridge models and at both sites. Specifically, spectral matching produced means closer to the CSS benchmark and more consistent predictions of peak drift ratios across suites.]]></description>
      <pubDate>Mon, 23 Feb 2026 11:19:43 GMT</pubDate>
      <guid>https://trid.trb.org/View/2668494</guid>
    </item>
    <item>
      <title>The Experimental Study of the Harmonic Composition of String Vibrations in the String Converters When the String Length and the Point of Application of the Excitation Pulse Change</title>
      <link>https://trid.trb.org/View/2407850</link>
      <description><![CDATA[The article is devoted to the study of the string vibration amplitude of a string converter with a constant string tension force. The article considers its dependence on the string length and the point of application of the excitation pulse. The research was carried out on a prototype of a string converter which implements technical solutions under the patent of the Russian Federation. No. 2685803. The article presents the results of theoretical and experimental studies showing the influence of highest harmonics on the amplitude of string vibrations. The factors determining the harmonic composition of the string vibration and the contribution of the highest harmonics to the resulting amplitude of its vibrations are analyzed. The relationship between the measurement error of the controlled parameter and the relative position of the source of string vibrations excitation and the converter of these vibrations into an electrical signal is established. The article suggests ways to expand the measurement range by using string transducers with a constant string tension force.]]></description>
      <pubDate>Fri, 21 Mar 2025 16:02:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/2407850</guid>
    </item>
    <item>
      <title>Automatic Parameter Scheduling of Equivalent Circuit Battery Models Using Local Linear Model Trees and Amplitude-Modulated Pseudo-Random Excitation Signals</title>
      <link>https://trid.trb.org/View/2452496</link>
      <description><![CDATA[The automotive industry is moving rapidly to electrification through development of Battery Electric Vehicles (BEV). Development and sizing of the battery and powertrain requires a detailed understanding of battery cell behavior under different conditions. Achieving this is difficult due to the range of cells available and the large range of condition variables of each cell. Equivalent-circuit models are used for BEV development. However, conventional battery cell characterization testing to parameterize these models are time and resource intensive. Characterization can be performed using well-known techniques such as Hybrid Pulse Power Characterization (HPPC) or Galvanostatic Intermittent Titration Technique (GITT) which are used to optimize parameters of an ESC model pertinent to the dynamics of its voltage response. However, the discrete State-of-Charge (SoC) intervals and demand current amplitudes of these experiments are not optimized for a balance of time and model effectiveness. There is scope to develop methods that can excite a range of current amplitudes and SoC points in a shorter timeframe whilst revealing non-linearities in the system’s time response. In this work an excitation signal design is presented that aims to maximize the amount of information gained about the dynamics of the battery across the SOC range within a short timeframe. An automated means of parameter-scheduling an ESC model is also introduced to best utilise the data from such a randomized, unstructured experiment. The excitation signal design takes the form of pulse signals with pseudo-randomly generated amplitudes and duration, constrained to ensure a specified test duration. This data is used to characterize a variant of the ESC model that automatically schedules parameters of the model via self-organizing Locally Linear Model Trees (LoLiMoT). The resulting models have strong predictive capability even in the extreme low SOC condition, resulting in an 18% reduction in Mean Absolute Error when compared to an ESC model without parameter scheduling over a validation cycle. This constitutes a strong step toward rapid, robust battery modelling processes for the purpose of cell selection and simulation for powertrain/vehicle design.]]></description>
      <pubDate>Mon, 18 Nov 2024 17:08:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/2452496</guid>
    </item>
    <item>
      <title>On vehicle response under non-Gaussian road profile excitation</title>
      <link>https://trid.trb.org/View/2373972</link>
      <description><![CDATA[Gaussian road profile is widely used to study vehicle response and fatigue damage potential, while field measured road profile often is non-Gaussian. In this paper, a new amplitude modulation method which has full control of cutoff frequency (denoted as Wcut) and amplitude of the amplitude modulation signal is firstly presented to synthesize non-Gaussian road profile with different kurtosis. The forced response of a quarter vehicle under non-Gaussian road profile excitation is then calculated using the ramp invariant digital filter method. The relationship between the vehicle response characteristics and the kurtosis of input non-Gaussian road profile are developed. A case study is used to verify the proposed method. The results show that a small Wcut should be selected so that the high kurtosis of the non-Gaussian road profile is correctly transferred to the vehicle response. The Fatigue damage spectrum (FDS) of the vehicle response increases over the entire frequency range as the kurtosis of the input road profile increases.]]></description>
      <pubDate>Thu, 09 May 2024 16:15:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/2373972</guid>
    </item>
    <item>
      <title>Overview of Multilevel Inverter Topologies and Modulation Methods</title>
      <link>https://trid.trb.org/View/2113743</link>
      <description><![CDATA[Multilevel inverter has the advantages of good power quality, high inverting efficiency, small electromagnetic interference and so on. It is widely used in power system, power transmission, motor drive, electromagnetic launch and other large power conversion occasions. In this paper, a brief overview of multilevel inverter topologies is given to provide ideas for the construction of multilevel inverters with different applications and characteristics. The main research achievements of existing multilevel inverter technologies are mainly introduced, including classic multilevel topologies, new multilevel topologies, classic modulation methods, and optimized modulation methods. The common topologies are compared, and the new applications of multilevel inverter in various fields are introduced. The development trend of multilevel inverter technology and the latest progress in control are pointed out, which provides a reference for the wide application of multilevel inverter technology in industry.]]></description>
      <pubDate>Fri, 21 Apr 2023 09:51:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/2113743</guid>
    </item>
    <item>
      <title>Evaluation of an in situ QAM-based Power Line Communication system for lithium-ion batteries</title>
      <link>https://trid.trb.org/View/2035642</link>
      <description><![CDATA[Power Line Communication (PLC) is used to transmit high-fidelity data on internal cell characteristics from within instrumented cells to an external Battery Management System (BMS). Using PLC is beneficial, as it avoids the need for a complex and heavyweight wiring harness within a battery. The use of advanced modulation, such as Quadrature Amplitude Modulation (QAM), is considered here. The existing experimental results of lithium-ion cell impedance characteristics for frequencies of 100 kHz-200 MHz are exploited in order to create a realistic battery model. This model is used to determine the effectiveness and optimal properties of PLC with QAM, as a means of in situ battery communication for Battery Electric Vehicles (BEVs) in combination with a real-world dynamic drive profile. Simulations reveal that the performance of the PLC system is heavily dependent on the selected carrier frequency due to the significant changes in reactance and internal resistance of the lithium-ion cells tested. Furthermore, cells placed in parallel display a decreased performance compared with cells in series. The results highlight that the optimal carrier frequency for in situ QAM-based PLC for a lithium-ion battery system is 30 MHz, and that additional signal conditioning is required for 4-QAM and higher modulation orders.]]></description>
      <pubDate>Mon, 28 Nov 2022 10:56:47 GMT</pubDate>
      <guid>https://trid.trb.org/View/2035642</guid>
    </item>
    <item>
      <title>Intentional Navigation and Phase Transition Analysis in Amygdala of KIV Model</title>
      <link>https://trid.trb.org/View/1806402</link>
      <description><![CDATA[Previous study on the KIV model proved that it is feasible to extract information from the amygdala for navigation tasks. In this work, the authors observed the chaotic dynamics of the KIV model by analyzing the global phase transitions that occur in the amygdala. By using the Hilbert transform, the authors are able to capture the fast global synchronized spatial patterns of amplitude modulation (AM) in the Amygdala. The ultimate goal for identifying the phase transition within the amygdala is to aid the system for decision-making while navigating in a challenging environment with an intentional behavior. In this paper, the authors will concentrate on the phase transition analysis in the amygdala of the KIV model. The authors experiment has shown the detection of phase transition in the amygdala can be done by Hilbert transform.]]></description>
      <pubDate>Fri, 30 Sep 2022 12:09:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/1806402</guid>
    </item>
    <item>
      <title>Experimental investigation on vortex-induced force of a flexible pipe under oscillatory flow</title>
      <link>https://trid.trb.org/View/2005379</link>
      <description><![CDATA[In this paper, vortex-induced force (VIF) characteristics of a flexible pipe under oscillatory flow are experimentally investigated with different KC numbers ranging from 10 to 178, and reduced velocities from 4 to 7.9. The strain information caused by vortex-induced vibration (VIV) at different cross-sections on the flexible cylinder is measured in the model test. Combined with the modal superposition method and inverse analysis method for hydrodynamic force, the hydrodynamic forces on the flexible cylinder are inverted, including the excitation force in phase with velocity and added mass force in phase with acceleration. Then, through a least square method with forgetting factors, the excitation coefficients and added mass coefficients at each time step are identified. The results show that the VIV excitation coefficient of a flexible pipe under oscillatory flow has a significant “acceleration and deceleration” effect, that is, the excitation coefficients are mostly positive at the acceleration section of the oscillatory flow and negative at the deceleration section. This “acceleration and deceleration” effect also explains the response amplitude modulation feature of VIV under oscillatory flow. And this effect can be represented by the dimensionless acceleration parameter γ of the flow field, and the range of γ corresponding to the positive excitation coefficient is affected by the KC number and the maximum reduced velocity. In addition, the added mass coefficients present different time-varying features under oscillatory flow with different maximum reduced velocity. When the maximum reduced velocity is larger than 6.5, the time-varying trend of the added mass coefficient is opposite to that of the flow velocity. While when the maximum reduced velocity is smaller than 6.5, the added mass coefficient is maintained around 2.0 in VIV excitation region; and it is around 1.0 in the non-excited region which is close to the added mass coefficient of a cylinder in still water.]]></description>
      <pubDate>Fri, 26 Aug 2022 16:49:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/2005379</guid>
    </item>
    <item>
      <title>Doppler Measurement of Modulated Light for High Speed Vehicles</title>
      <link>https://trid.trb.org/View/1920718</link>
      <description><![CDATA[Technical details associated with a novel relative motion sensor system are elaborated in the paper. By utilizing the Doppler effect, the optical sensor system estimates the relative motion rates between the sensor and the moving object equipped with modulating light sources and relatively inexpensive electrical components. A transimpedance amplifier (TIA) sensing circuit is employed to measure the Doppler shift exhibited by the amplitude modulated light sources on the moving platform. Implementation details associated with the amplitude modulation and photo-detection processes are discussed using representative hardware elements. A heterodyne mixing process with a reference signal is shown to improve the signal-to-noise ratios of the Doppler shift estimation processing pipeline. Benchtop prototype experiments are used to demonstrate the utility of the proposed technology for relative motion estimation applications.]]></description>
      <pubDate>Fri, 18 Mar 2022 12:17:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/1920718</guid>
    </item>
    <item>
      <title>Large Amplitude Oscillatory Shear to Quantify Elastic and Viscous Nature of Aged and Unaged Bitumen at Different Temperatures</title>
      <link>https://trid.trb.org/View/1856930</link>
      <description><![CDATA[The temperature-sensitive characteristic of the bitumen plays a critical role in the performance of the bituminous binder. The accumulation of distress over a range of temperature depends on the proportion of elastic and viscous behavior of the binder. This paper attempts to separate the elastic and viscous behavior of binder at different temperatures and aging conditions using large amplitude oscillatory shear (LAOS) testing. A binder of VG30 grade as per Indian standard specification was used for this study. The material was sheared using constant strain amplitude for 10 min using a dynamic shear rheometer. Unaged, short-term aged, and long-term aged VG30 binder were subjected to 1% and 5% strain amplitude and the test was conducted at 5 Hz frequency. The test was conducted at the temperatures of 30°C, 45°C, and 60°C. The stress, strain, and strain rate waveform data were used to separate the elastic and viscous stress. The elastic and viscous stress was further used in studying the elastic/viscous behavior dominance at a specific temperature.]]></description>
      <pubDate>Wed, 30 Jun 2021 11:59:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/1856930</guid>
    </item>
    <item>
      <title>Slug flow's intermittent feature affects VIV responses of flexible marine risers</title>
      <link>https://trid.trb.org/View/1696889</link>
      <description><![CDATA[Slug flow is characterized by the variations of internal flow parameters with time and position. This study aims to investigate the slug flow effect (SFE) on the cross-flow Vortex-Induced Vibration (VIV) of a flexible riser. A steady slug-flow model is adopted using several assumptions and empirical correlations. A distribution of van der Pol oscillators is employed to create the VIV effect. A novel approach has been proposed to capture the intermittent feature which is validated by comparisons with experiments. The SFE is explored by comparisons of the dynamic behaviors of a flexible riser subject to two uniform currents, assuming the pipe is filled with still liquid, transporting a single-phase liquid flow and a two-phase slug flow. It has demonstrated that the SFE is much more profound than the single-phase internal flow effect. A flexible riser conveying a slug flow can exhibit quite distinguished dynamics owing to the intermittent feature. Apart from triggering new modes, the combination of slug flow frequency and VIV frequency can generate an amplitude-modulation phenomenon of excited modes. Most distinctively, beating behaviours which corresponds to the resonant synchronization have been captured. This study can contribute to fatigue analysis of a flexible riser conveying a two-phase slug flow.]]></description>
      <pubDate>Fri, 26 Jun 2020 09:51:51 GMT</pubDate>
      <guid>https://trid.trb.org/View/1696889</guid>
    </item>
    <item>
      <title>Aerodynamic Response of a Bridge Girder Segment during Lifting Construction Stage</title>
      <link>https://trid.trb.org/View/1607404</link>
      <description><![CDATA[Investigations on the wind loads and aerodynamic responses of the bridge girder segment during the lifting construction stage are limited. Free vibration tests of a lifting girder segment of a kilometer-span cable-stayed bridge were carried out in a wind tunnel to study its aerodynamic performance. Large aerostatic displacements were observed in the wind velocity range of concern. Large-amplitude limit cycle oscillations (LCOs) around the horizontal axis perpendicular to the bridge span occurred when the full-scale velocity exceeded 25.3 m/s. The analytical expression of the eigenfrequency of the dangerous mode of a lifting girder segment was derived, and the analytical result was compared with those determined by using the finite-element analysis (FEA) and testing results. The characteristics of the large-amplitude LCOs under different conditions were thoroughly analyzed. For various testing cases, the influences of the angle of attack, wind velocity, and vibration amplitude on the vibration frequency and aerodynamic damping ratio were comprehensively investigated and the parameter identification accuracies were verified. It was demonstrated that more attention should be paid to assessing the wind-resistance of lifting girder segments to ensure the construction safety of long-span bridges. The results of the present work can provide beneficial reference for evaluating the wind-resistance performances of similar types of lifting girder segments.]]></description>
      <pubDate>Thu, 13 Jun 2019 17:29:12 GMT</pubDate>
      <guid>https://trid.trb.org/View/1607404</guid>
    </item>
    <item>
      <title>A Novel Regenerative Electrohydraulic Brake System: Development and Hardware-in-Loop Tests</title>
      <link>https://trid.trb.org/View/1575976</link>
      <description><![CDATA[The development of a novel electrohydraulic brake system named REHB is presented in this paper. Neither high-pressure accumulator nor linear valves are adopted to reduce the system cost, the difficulty of manufacturing, assembling, and the risk of leakage. Stroke simulators are implemented to elevate the quality of pedal feel. The braking force blending control strategy is well designed to coordinate regenerative and friction brake force, which has ensured maximized regenerative brake force. In the aspect of underlying control, current amplitude modulation control is adopted to improve the accuracy of hydraulic pressure modulation and eliminate vibration noise. High fidelity models of vehicle and brake system are built based on MATLAB-AMESim co-simulation platform. Three demand levels of one-step-brake scenarios are simulated. Simulation results show the reasonability of proposed hydraulic structure and designed control strategy. A regenerative brake test bench is set up based on a prototype of the developed system. Three identical one-step-brake experiments are conducted on the test bench. According to the bench test results, the blending of regenerative and friction brake force tracks driver brake demand adequately well. Regenerative efficiencies are calculated as 46.32%, 43.93%, and 31.88%, respectively, in three bench tests. Compared with the previous generation, no obvious valve buzzing noise is observed, and jerks are whittled significantly. REHB has provided a brake-by-wire solution of safety, high energy recuperation efficiency with low cost, and uncompromising performance.]]></description>
      <pubDate>Fri, 22 Mar 2019 16:15:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/1575976</guid>
    </item>
    <item>
      <title>Vehicle Positioning and Trajectory Tracking by Infrared Signal-Direction Discrimination for Short-Range Vehicle-to-Infrastructure Communication Systems</title>
      <link>https://trid.trb.org/View/1500436</link>
      <description><![CDATA[In this paper, the authors propose a reliable method to determine the coming direction of an infrared signal, where the direction of the signal sent by the vehicle relative to the receiver is determined by amplitude comparison. The authors utilize a simple symmetric structure comprising four identical planar receiving modules, each with a specific tilt angle relative to the receiving plane, to construct the receiver. The coming direction of the signal is extracted by comparing the signal strengths received by these four receiving modules. With the aid of a simple geometric relation, the trajectory of a vehicle is tracked, i.e., its positions are located, from the coming direction of the signal originated from this vehicle when it travels through the communication area of the system. For several vehicles simultaneously appearing in the communication area, the vehicles can be distinguished in the frequency domain from different frequencies sent by different vehicles. According to signal-direction discriminator proposed by the authors in this paper, it is able to locate the position of the vehicle in a communication area of 6 m in width and 20 m in length. In the lateral direction, this area sufficiently covers a typical traffic lane; in the longitudinal direction, it meets the general requirements of shorter than 20 m for common short-range vehicle-to-infrastructure communication systems, such as electronic-toll-collection applications.]]></description>
      <pubDate>Thu, 22 Mar 2018 12:01:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/1500436</guid>
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