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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" />
    <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>Optimization of power system parameters for multi-mode hybrid electric vehicles based on regional demand</title>
      <link>https://trid.trb.org/View/2608030</link>
      <description><![CDATA[The performance of the vehicle power system for multi-mode hybrid electric vehicle (M-MHEV) can be improved through meticulous parameter matching and optimization. This paper developed the powertrain parameter design and dynamic performance calculation program based on the structure design, parameter matching calculation, and powertrain system selection. A HOQM of M-MHEV is formulated to ascertain the weight coefficient of vehicle performance indicators according to different regional requirements and a parameter matching and optimization method for power system, employing the Particle Swarm Optimization (PSO) algorithm, is suggested to assess and harmony the vehicle’s performance. Firstly, a house of quality model of M-MHEV is constructed to ascertain the weight coefficient of vehicle performance indicators derived from different regional demands. Additionally, a method is introduced for optimization of power system parameters of M-MHEV based on regional demand, the PSO algorithm is employed to optimize the characteristic parameters. And sensitivity analysis of characteristic parameters is conducted relying on user needs in different regions. The simulation results show that users in the northern and southern regions have different final weight coefficients for vehicle performance indicators and the parameters not only exert a substantial individual influence but also exhibit an interaction effect on the vehicle performance. Finally, a series of comparative simulations, are carried out with two optimization parameters respectively, the simulation outcomes demonstrate that the solution obtained through optimized design parameters solution could markedly enhance the technical parameters of the vehicle. The efficacy and viability of the proposed method based on user needs in different regions are verified. The conclusion provides a useful reference for differentiated design.]]></description>
      <pubDate>Mon, 15 Dec 2025 10:33:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/2608030</guid>
    </item>
    <item>
      <title>Energy management and health monitoring for hybrid ship power plants</title>
      <link>https://trid.trb.org/View/2582940</link>
      <description><![CDATA[Intelligent real-time management and monitoring of ship power plants’ performance and health state are essential to develop autonomous ships and operate uncrewed engine rooms. This study proposes a novel methodology to integrate the energy management strategy with the health monitoring for the hybrid power plant of a short-sea shipping vessel. The energy management strategy employs the equivalent consumption minimisation strategy (ECMS), whereas the health monitoring is based on Dynamic Bayesian Networks (DBNs) with the components' failure rates being updated using a Wiener process model (WPM), considering the operating conditions history. The proposed methodology is demonstrated and verified by investigating a scenario of 500 h of operation. The results demonstrate that the energy management strategy results in achieving engine operation with high efficiency, whereas the battery reaches the set state of charge in each operating mode. The health monitoring indicates that the turbocharger compressor is the most critical component for the first 320 h of operation, whereas cooling water pumps become most critical afterwards. The reliability time variation reveals challenges in achieving 500 h of autonomous operation. This study provides insights for the integration of energy management with health monitoring; hence contributing to the development of intelligent decision support systems for autonomous ships.]]></description>
      <pubDate>Fri, 26 Sep 2025 13:39:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/2582940</guid>
    </item>
    <item>
      <title>Selection of the Ship's Propulsion Complex Taking into Account the Criteria of Energy Efficiency of the Ship Power Plant</title>
      <link>https://trid.trb.org/View/2406942</link>
      <description><![CDATA[The main criterion for the modernization and design of ships is their energy efficiency. The paper describes the method of selecting the composition and main parameters of the propulsive complex of a marine transport ship, and suggests criteria for evaluating this choice. The most important criteria from the point of view of energy efficiency of ship power plants are determined. Using this technique, the problem of choosing the number of propeller shafts in the design of high-speed transport ships is solved. The problem is solved in relation to the RO-RO ship of the “Sergey Kirov” type (design speed of 17 knots) and the FESCO container ship Baikal (design speed of 22 knots). As criteria for evaluating design solutions, a set of values is used: the propulsive coefficient, the hourly fuel consumption in the main engines and the total cost of funds for the purchase and operation of the main engines during the estimated period.]]></description>
      <pubDate>Thu, 24 Jul 2025 11:31:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/2406942</guid>
    </item>
    <item>
      <title>Enhancement of Two-Motor Hybrid Engine Start-up Vibration Performance by Motor Starting Torque Control Considering Power Plant Resonance</title>
      <link>https://trid.trb.org/View/2556922</link>
      <description><![CDATA[In order to suppress the variation in body vibration at the start-up of a compact two-motor hybrid vehicle, this study focused on the coupling between the initial frequency of the input shaft torque fluctuation due to the forcing force, in addition to the torsional damper resonance and power plant rigid body resonance, which are the causes of the vibration. By increasing the starting torque rise, these coupling effects were avoided, power plant vibration was reduced, and the variation in body vibration was reduced to the same level as the target for a mid-size vehicle.]]></description>
      <pubDate>Thu, 26 Jun 2025 16:12:49 GMT</pubDate>
      <guid>https://trid.trb.org/View/2556922</guid>
    </item>
    <item>
      <title>A Method for Calculating Power Plant Order-Based Frequency Response Functions Using Finite Element Model</title>
      <link>https://trid.trb.org/View/2529552</link>
      <description><![CDATA[This study reports the development of a method for calculating an Order-based FRF using CAE analysis with a finite element model (FEM) for enhancing the sound quality of engine combustion noise. An FEM was created from a power plant model equivalent to a bench vibration test, and it was confirmed that an Order-based FRF similar to the experiment could be calculated. In order to simplify the analysis model, verification was carried out, so the main motion system model was omitted and a method of inputting the excitation force to the main bearing was considered. As a result, it was found that an Order-based FRF equivalent to the actual machine experiment could be calculated with only the power plant structure model. By using the CAE analysis method constructed in this study to calculate the Order-based FRF, it is possible to identify the frequency band and mode of concern for sound quality deterioration and to consider countermeasures at the pre-prototype stage.]]></description>
      <pubDate>Wed, 09 Apr 2025 09:52:23 GMT</pubDate>
      <guid>https://trid.trb.org/View/2529552</guid>
    </item>
    <item>
      <title>The Impact of Vehicle Engine Characteristics on Vehicle Exhaust Emissions for Transport Modes in Lagos City</title>
      <link>https://trid.trb.org/View/2458828</link>
      <description><![CDATA[The study delves into how vehicle engine characteristics impact the release of air pollutants from various vehicle fleets in Lagos, Nigeria. It involved the direct measurement of emissions from the exhaust pipes of 88 vehicles using gas analyzers. The vehicle fleets encompassed motorcycles, tricycles, private cars, minibuses, large buses, and trucks. A statistical analysis was conducted on carbon monoxide (CO) and nitrogen oxide (NOx) emissions to develop a model equation based on vehicle type, engine type, vehicle age, and purchase status. Results indicate that personal cars and minibuses predominantly emit CO from gasoline engines, whereas large buses and trucks significantly contribute to NOx emissions from diesel engines. Further scrutiny revealed that 66% of the vehicles examined were over 10 years old, resulting in a 65% increase in emission levels. Approximately 60% of gasoline and 75% of diesel vehicles exceeded the permissible emission limits, leading to air quality deterioration and heightened health risks. The study underscores the risks associated with ageing vehicles and different engine types, emphasizing the imperative for a gradual transition to low-carbon or electric vehicles in developing African cities to combat air pollution and mitigate health hazards.]]></description>
      <pubDate>Mon, 16 Dec 2024 11:59:21 GMT</pubDate>
      <guid>https://trid.trb.org/View/2458828</guid>
    </item>
    <item>
      <title>Analysis of fuel consumption and noise of a regional turbopropeller aircraft with a hybrid power plant</title>
      <link>https://trid.trb.org/View/2450508</link>
      <description><![CDATA[This article assesses the ecological efficiency of hybrid-electric aircraft (HEA) and simulates their parameters using a regional aircraft as an example. The noise problem is addressed by modernising the power plant of the An-26 aircraft. The proposed noise reduction method involves optimising the operating modes of engines. The sound pressure level created by the HEA at certification points was used as the optimisation criterion. The acoustic characteristics of HEA propellers are calculated using the Gutin-Deming model. The HEA flight trajectories were determined based on the results of solving the system of differential equations. The results of the calculations showed that the use of optimal HEA operating procedures allows for reduced fuel consumption and reduced noise in the area. The reduction of 70 dB SEL contour area was 50.6% during takeoff and 21.9% during landing. A maximum reduction of 2.8 EPNLdB was achieved at the flyover certification point for HEA.]]></description>
      <pubDate>Tue, 19 Nov 2024 14:39:49 GMT</pubDate>
      <guid>https://trid.trb.org/View/2450508</guid>
    </item>
    <item>
      <title>Multi-objective parameter optimization strategy based on engine coordinated control for improving shifting quality</title>
      <link>https://trid.trb.org/View/2329963</link>
      <description><![CDATA[In order to address the poor shifting quality issue of a certain model of heavy-duty vehicles, a multi-objective parameter optimization strategy based on engine coordinated control is proposed. This strategy aims to improve shifting quality by reducing the sliding friction work and impact during the shifting process. The Non-Dominated Sorting Genetic Algorithm II (NSGA-II) is employed to perform multi-objective optimization on the coordinated control parameters, which include external control torque of the engine, start of fuel cut-off timing, and duration of fuel cut-off. By comparing the performance of different parameter combinations in terms of sliding friction work and impact, the optimal parameter combination is determined. Through bench testing verification, it has been demonstrated that utilizing the optimized parameters for engine coordinated control during the torque phase of the shifting process can significantly enhance shifting quality. This strategy provides an effective solution for addressing shifting quality issues.]]></description>
      <pubDate>Tue, 27 Feb 2024 16:03:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/2329963</guid>
    </item>
    <item>
      <title>Model Free Time Delay Compensation for Damped Impedance Method Interfaced Power System Co-Simulation Testing</title>
      <link>https://trid.trb.org/View/2289558</link>
      <description><![CDATA[The joint real-time co-simulation, which involves the virtual integration of laboratories located in different locations, is met with challenges, especially the communication latency or delay, which significantly affects co-simulation accuracy and system stability. The real-time power system co-simulation is particularly susceptible to these delays and could lose synchronism, which affects the simulation fidelity and limits dynamic and transient studies. This paper proposes a model-free framework for predicting and compensating delays in the virtual integration of real-time co-simulators through the damped impedance interface method to address this issue. The framework includes an improved co-simulation interface algorithm called the Damping Impedance Method (DIM) and a model-free predictor system designed to predict and compensate for delays without decomposing and reconstructing signals at coupling points. The predictor systems use one design parameter and two design parameters to achieve delay compensation through a first-order time delay compensation system. The framework enhances the accuracy and stability of the system, making it suitable for dynamic and transient studies.]]></description>
      <pubDate>Mon, 20 Nov 2023 16:06:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/2289558</guid>
    </item>
    <item>
      <title>Aspects of Remote Monitoring of the Transport Vessel Under Operating Conditions</title>
      <link>https://trid.trb.org/View/1975266</link>
      <description><![CDATA[Remote monitoring is one of the most important steps in operating of a modern transport vessel. Monitoring of technical condition includes the use of vehicle-to-infrastructure (V2I) systems for the formation and application of separate systems of the ship power plant maintenance and repair. The information V2I model developed by the authors is characterized by the vibrational field of the transport vessel, means of monitoring of the technical condition parameters and infrastructure components for monitoring of any transport vessel. The article describes the features of the information V2I system, the process of preparation, monitoring and assessment of the technical condition of the transport vessel power plant under operating conditions with the possibility of predicting its technical condition. The main idea is to implement the information V2I system for monitoring of the technical condition of the transport vessel power plant in the practice of transport operation.]]></description>
      <pubDate>Thu, 23 Feb 2023 09:31:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/1975266</guid>
    </item>
    <item>
      <title>Transverse impact response of hybrid biaxial/uniaxial braided composite tubes</title>
      <link>https://trid.trb.org/View/2016158</link>
      <description><![CDATA[Tubular composites in automobile engineering are susceptible to transverse loading events. This paper deals with transverse low-velocity impacts on interply hybrid tubes made of biaxial/uniaxial braided fabric layers. For comparison, drop weight tests were performed on hybrid tubes with biaxial braided surface layers and uniaxial braided inner layer (BUB), with contrary stacking sequence (UBU), pure biaxial and uniaxial braided tubes (BBB and UUU). Numerical models were established to predict the impact behaviors and evaluate the hybrid effects. X-ray micro-computed tomography (Micro-CT) was also employed to identity the cracking location and characterize the damage mechanism. The results showed that the impact response of braided tube was related to its structural deformation resistance, which was determined by properties of reinforced layers varying with different stacking sequence. The hybrid effect became more obvious at higher impact energy. At impact energy of 15.4 J, hybrid tube (BUB) yielded the highest impact resistance with small structural deformation. The biaxial braided layer protected the specimen surface by constraining intralaminar crack propagation through the interlacing patterns. Meanwhile, it promoted crack tip propagating to the subsequent uniaxial braided layer and transferred the impact load. Thus, the material involvement of the inner layer was improved, which was responsible for providing a higher in-plane tensile property due to its low yarn crimp.]]></description>
      <pubDate>Thu, 17 Nov 2022 10:15:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/2016158</guid>
    </item>
    <item>
      <title>Study of Engine Vibration Due to Piston Slap on Single Cylinder High Powered Engine</title>
      <link>https://trid.trb.org/View/1802682</link>
      <description><![CDATA[The piston slap is an important phenomenon in the engine, which governs the vibration, noise, and wear of liner surfaces. It occurs due to transverse and rotational motion of piston, which depends on clearance between piston and liner and is governed by geometry, mass and inertia properties of reciprocating parts, and gaseous loads. Piston slap is studied on single cylinder high-powered engine, which showed large vibrations and noise during the field trials. The classical methodology is used to determine secondary movement, contact forces and kinetic energy loss due to piston impact. The calculated result showed no major impact of piston on liner surfaces due to presence of hydrodynamic lubrication between two mating surfaces. The loss of kinetic energy due to the impact is of the order of 0.007 Nm, which is negligibly small. The calculated values were compared with measured field trial and engine dynamometer test results, and observed predominant frequency value of 36 Hz, which is much lower to normal piston slap frequency value of 200 to 400 Hz. In addition, the engine endurance experimental results showed no severe marks on the piston and liner surface. This clearly indicated that the problem is not due to piston assembly. The technique is extended to predict the wear of critical engine parts like piston and liner surface. Thus, the finite element method and piston transverse movement calculation technique is satisfactorily used to predict engine vibrations and noise due to piston slap.]]></description>
      <pubDate>Wed, 28 Sep 2022 16:56:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/1802682</guid>
    </item>
    <item>
      <title>Performance and Reliability Monitoring of Ship Hybrid Power Plants</title>
      <link>https://trid.trb.org/View/1938466</link>
      <description><![CDATA[Recently, the marine industry has been under a paradigm shift toward adopting increased automation, and initiatives to enable the autonomous operations of ships are ongoing. In these cases, power plants require advanced monitoring techniques not only for the performance parameters but also to assess the health state of their critical components. In this respect, this study aims to develop a monitoring functionality for power plants that captures the performance metrics while considering the overall system and its components’ reliability. A hybrid power plant of a pilot boat is considered a case study. A rule-based energy management strategy is adopted, which makes the decisions on the power distribution to the investigated power plant components. Additionally, a dynamic Bayesian network is developed to capture the temporal behavior of the system’s/components’ reliability accounting for the power plant’s operating profile. Results demonstrate that the selected hybrid power plant monitoring capabilities are enhanced by providing the power plant performance along with the estimation of the system’s health state. Furthermore, these extended monitoring capabilities can provide the essential metrics to facilitate decision making, enabling the autonomous operation of the power plant.]]></description>
      <pubDate>Mon, 22 Aug 2022 16:14:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/1938466</guid>
    </item>
    <item>
      <title>Distributed Power System Architecture for Electric Propulsion Applications</title>
      <link>https://trid.trb.org/View/1783936</link>
      <description><![CDATA[The Hall Effect Thrusters (HET's), which are presently available in a broad range of power levels, are recognized as an economic, efficient, and effective means to perform numerous propulsion functions for commercial and military satellite applications. Also, the HET technology is the preferred alternative for future constellations of LEO satellites, and several GEO applications. Power Processing Units (PPU's) for electric thrusters are very complex custom designs which require long and expensive development and qualification cycles. The core element of a HET PPU is its Discharge Power Supply (DPS) which processes more than 95% of the input power. Traditional DPS designs cannot easily accommodate parametric changes, and for severe thermal and EMI issues must be overcome high power applications. These custom approaches require lengthy developments, lack proven “heritage”, are costly. A distributed power architecture for the DPS, employing space-qualified high power density DC-to-DC converters (COTS), provides an attractive solution to the industry stringent demands for low-cost, light-weight, low-volume, shorter time-to-market, established heritage, development risk mitigation, and built-in redundancy.]]></description>
      <pubDate>Tue, 26 Jul 2022 13:18:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/1783936</guid>
    </item>
    <item>
      <title>Li-Ion Prismatic Cell Development and Performance</title>
      <link>https://trid.trb.org/View/1780998</link>
      <description><![CDATA[This paper is a summation of past, present and future work with Li-Ion cells. Direct emphasis will be placed upon the development of cycle life and related components. Other discussion includes: cell design, operational temperature variations, rate capability and energy density. Accelerated performance will be characterized both in GEO and LEO “on-orbit” profiles. To support findings and authenticity of the test data being presented, details of the test configuration and test parameters will be covered as applicable. In addition, future endeavors will be discussed, encompassing expected performance improvements and developmental planning. The intent is to keep the satellite community abreast of recent developments at the cell level and to help direct sound decisions in power system design variations from the current Nickel-Hydrogen (NiH2) and Nickel-Cadmium (NiCd) technologies.]]></description>
      <pubDate>Tue, 26 Jul 2022 13:18:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/1780998</guid>
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