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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+PHBhcmFtIG5hbWU9ImxvY2F0aW9uIiB2YWx1ZT0iMCIgLz48L3BhcmFtcz48ZmlsdGVycz48ZmlsdGVyIGZpZWxkPSJpbmRleHRlcm1zIiB2YWx1ZT0iJnF1b3Q7UmVzZWFyY2ggc2hpcHMmcXVvdDsiIG9yaWdpbmFsX3ZhbHVlPSImcXVvdDtSZXNlYXJjaCBzaGlwcyZxdW90OyIgLz48L2ZpbHRlcnM+PHJhbmdlcyAvPjxzb3J0cz48c29ydCBmaWVsZD0icHVibGlzaGVkIiBvcmRlcj0iZGVzYyIgLz48L3NvcnRzPjxwZXJzaXN0cz48cGVyc2lzdCBuYW1lPSJyYW5nZXR5cGUiIHZhbHVlPSJwdWJsaXNoZWRkYXRlIiAvPjwvcGVyc2lzdHM+PC9zZWFyY2g+" 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>Experimental study on the transport characteristics of bubbles at the bow of research vessels</title>
      <link>https://trid.trb.org/View/2682185</link>
      <description><![CDATA[Bubble sweep-down represents a critical phenomenon adversely affecting the performance of acoustic equipment on research vessels. To investigate the transport characteristics of bow-entrained bubbles under the hull wake effect, we conducted model tests with a scale ratio of 1:40 in a towing tank. A micro-nano bubble generator was employed to produce an air-water mixture simulating bubble clouds. The motion trajectories of bubbles across multiple cross-sections were captured using high-speed photography combined with fluorescent tracer techniques. Through a self-developed image processing method, we systematically analyzed the morphological features and motion patterns of the bubble clouds. Results indicate that the width, height, and area of bubble clouds gradually increase along the flow direction, with their evolution significantly influenced by the vessel speed. At higher speeds, bubble clouds are more prone to sweep-down toward the vessel bottom and exhibit more pronounced shape variations. While the vertical motion of bubbles generally aligns with the flow streamlines, notable discrepancies are observed in the spanwise direction, reflecting the complex interaction between bubble dynamics and turbulent structures. This study provides experimental insights for optimizing the layout of acoustic equipment and developing effective strategies to mitigate bubble interference.]]></description>
      <pubDate>Wed, 25 Mar 2026 11:44:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/2682185</guid>
    </item>
    <item>
      <title>Model scale noise measurements of the research vessel Nawigator XXI propeller</title>
      <link>https://trid.trb.org/View/2682224</link>
      <description><![CDATA[In the last decades, the prediction and mitigation of ships underwater radiated noise have become an important matter of study for research institutions in naval hydrodynamics, mostly because of the adverse impacts that anthropogenic noise may have on marine ecosystems. Propellers are commonly recognized as the main noise sources, when cavitating, therefore large effort is dedicated to the prediction of propeller cavitation and noise. Model scale noise measurements represent the oldest approach to perform this task, and its effectiveness is generally rather good. Yet the extrapolation of full scale noise from model tests presents many challenges associated to the many scale effects involved, as well as the effects of the adopted facility and experimental procedure. In this framework, the availability of comparisons between model test results and sea trials, as well as comparative studies among various facilities is of utmost importance to define and improve proper testing and scaling procedures for cavitating propeller noise. This work presents the results of the extensive experimental campaign carried out at the University of Genova cavitation tunnel on the model propeller of the research vessel Nawigator XXI. This propeller will be the object of the Round Robin test program planned within the International Towing Tank Conference, therefore current work will provide valuable information on this important test case in the view of future analyses and comparisons.]]></description>
      <pubDate>Wed, 25 Mar 2026 11:44:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/2682224</guid>
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    <item>
      <title>Flow-induced bubble sweep-down and vortex-governed bubble transport in the bow region of a research vessel under drift conditions</title>
      <link>https://trid.trb.org/View/2682957</link>
      <description><![CDATA[This study investigates the coupled mechanisms of flow-induced bubble sweep-down and vortex-governed transport in the bow region of a research vessel under drift conditions. A validated coupled Eulerian–Lagrangian framework is employed, integrating the Improved Delayed Detached Eddy Simulation (IDDES) for turbulence, the Volume of Fluid (VOF) method for the Eulerian multiphase flow (air–water interface), and a Lagrangian particle-tracking method for discrete bubbles. This approach resolves the multiscale interactions between hull-generated vortices and bubble particles under both straight and oblique sailing. Results show that drift angle fundamentally reshapes the bow flow topology, inducing strong asymmetry: a “Sidewall Down-sweep” on the windward side driven by water pile-up, versus complex vortex entrainment on the leeward side. A critical drift-dependent transition in bubble transport is identified. At moderate drift angles, lateral forces cause bubbles to separate from the bilge vortex. At large drift angles, “Cross-flow Transport” dominates, whereby windward-side bubbles traverse the hull bottom and are captured by the leeward vortex system—a process that clearly exemplifies vortex-governed transport. These findings elucidate the spatiotemporal evolution of bubble clouds under realistic navigation conditions and provide direct theoretical guidance for optimizing the placement of hull-mounted acoustic equipment.]]></description>
      <pubDate>Wed, 25 Mar 2026 11:44:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/2682957</guid>
    </item>
    <item>
      <title>An adaptive control method of non-metallic armoured Optical-electrical cable winch system in Oceanographic Research Vessel based on three-dimensional laser scanning point cloud</title>
      <link>https://trid.trb.org/View/2557331</link>
      <description><![CDATA[Non-metallic armoured optical-electrical cables facilitate the deployment and retrieval of deep-sea exploration equipment at extreme ocean depths. However, the deformation of non-metallic materials due to multi-layer spooling presents a significant challenge to maintaining a neat cable arrangement, adversely affecting deployment efficiency and operational safety. This paper presents a three-dimensional (3D) laser scanning-based cable monitoring system for real-time cable condition assessment. A point cloud completion technique extracts critical deformation features by real-time capture of cable deformation and positional changes. By monitoring and reconstructing the 3D status of optical cables, the system offers feedback for precise level-wind mechanism control, dynamically adjusting winch parameters in real-time through an adaptive strategy to compensate for uncertainties from cable variations, thus ensuring orderly cable arrangement and boosting efficiency and reliability. The efficiency of the proposed approach is validated through spooling tests on a full-ocean-depth optical-electrical cable winch, demonstrating its potential to enhance cable management and stability in deep-sea operations.]]></description>
      <pubDate>Thu, 05 Jun 2025 13:30:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/2557331</guid>
    </item>
    <item>
      <title>Solgenia - A Test Vessel Toward Energy-Efficient Autonomous Water Taxi Applications</title>
      <link>https://trid.trb.org/View/2527344</link>
      <description><![CDATA[Autonomous surface vessels are a promising building block of the future’s transport sector and are investigated by research groups worldwide. This paper presents a comprehensive and systematic overview of the autonomous research vessel Solgenia including the latest investigations and recently presented methods that contributed to the fields of autonomous systems, applied numerical optimization, nonlinear model predictive control, multi-extended-object-tracking, computer vision, and collision avoidance. These are considered to be the main components of autonomous water taxi applications. Autonomous water taxis have the potential to transform the traffic in cities close to the water into a more efficient, sustainable, and flexible future state. Regarding this transformation, the test platform Solgenia offers an opportunity to gain new insights by investigating novel methods in real-world experiments. An established test platform will strongly reduce the effort required for real-world experiments in the future.]]></description>
      <pubDate>Wed, 16 Apr 2025 11:26:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/2527344</guid>
    </item>
    <item>
      <title>Multidomain Device-Level Fuel-Cell Modeling and Real-Time Hardware Emulation for Marine Research Vessel Power System</title>
      <link>https://trid.trb.org/View/2364887</link>
      <description><![CDATA[Marine research vessels (MRVs) are redesigned and refurbished to meet higher energy conversion efficiency and modular integration schemes while conforming to stronger environmental regulations. The proton exchange membrane fuel cell (PEMFC) is currently regarded as a potential power source for marine transportation applications due to its advantages of stability, sustainability, and zero emissions. This article proposes a hierarchical scheme for the real-time hardware emulation of the MRV’s power system and a comprehensive multidomain model for PEMFCs. The PEMFC model is presented in the electrochemical, hydration, and thermal domains by ordinary differential equations considering the interactions and dynamics of each domain. Meanwhile, the multidomain PEMFC model considers the implications of the fluctuating supply of the onboard hydrogen circulation system. Moreover, the dynamics of the lithium-ion battery stacks are represented by an equivalent circuit model which considers heat flux phenomena. In the case study, the dc–ac grid of the MRV’s power system and electric propulsion system is configured using extensive electrification technology with an average model. The real-time hardware emulation is conducted on the Xilinx UltraScale+ VCU118 FPGA platform to execute the device-level and system-level behavior transients of the MRV. The results of the real-time hardware emulation have been validated against the full-scale hybrid MRV power system emulation over a wide operating range.]]></description>
      <pubDate>Thu, 30 May 2024 13:56:39 GMT</pubDate>
      <guid>https://trid.trb.org/View/2364887</guid>
    </item>
    <item>
      <title>Shipboard crane digital twin: An empirical study on R/V Gunnerus</title>
      <link>https://trid.trb.org/View/2362546</link>
      <description><![CDATA[The maritime industry is constantly facing new challenges and technological advancements, making the adaptation of innovative solutions like digital twins a bridge enhancing safety and efficiency between theoretical models and real-world maritime applications. Digital twin simulators for complex dynamic operation systems such as shipboard cranes, allow the operators to practice demanding operations in a risk-free immersive environment with various scenarios. This paper presents the process of developing a digital twin-based simulation tool designed for shipboard crane operations. It is based on co-simulation using the Functional Mock-up Interface (FMI) standard. This allows for the integration of the operation scenarios with different physical domain models, including such as the ship, environmental forces, hydraulic power systems, and controllers. In addition, the digital twin has opened up new opportunities for the optimization of maritime systems. It can be used to identify the optimal operating conditions, predict potential risks, and provide onboard support to the operator. A demo crane digital twin is implemented for the Palfinger crane on the Gunnerus research vessel with system validation via a series of marine operations being real-time monitored by the Remote Control Center (RCC).]]></description>
      <pubDate>Tue, 14 May 2024 16:30:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/2362546</guid>
    </item>
    <item>
      <title>Occurrence and characteristics of microplastics in greywater from a research vessel</title>
      <link>https://trid.trb.org/View/2295277</link>
      <description><![CDATA[The discharge of greywater from ships, an uncounted sea-based source of microplastics (MPs), is a growing concern. Yet, empirical data on MPs from this source are currently limited. Here, the abundances and characteristics of MPs in greywater from a research vessel were investigated according to water usage type (e.g., galley, cabin, and laundry). The mean abundance of MPs was highest in greywater from the laundry (177,667 n/m³), followed by the cabins (133,833 n/m³) and galley (75,000 n/m3). However, no significant differences were found in the MP abundances among greywater types due to high variability of triplicate samples collected every five days. Fiber-type MPs accounted for 66% of the total MP abundance and fragment-type MPs for 34%. Microplastics in the size range of 100–200 μm exhibited the highest levels among size classes. The dominant polymer identified in all greywater samples was polyester (53%), followed by polypropylene (23%). Marine coating origin MPs (6.0%) were also observed in all types of greywater. The greywater generation rate during the cruise was 0.15 m³/person∙day. Annual MP emissions per person by the greywater discharge of the research vessel was estimated to be 4.1 × 10⁶ n/person∙year (equivalent to 3.0 g/person∙year).]]></description>
      <pubDate>Mon, 26 Feb 2024 15:42:36 GMT</pubDate>
      <guid>https://trid.trb.org/View/2295277</guid>
    </item>
    <item>
      <title>A comparison of physics-informed data-driven modeling architectures for ship motion predictions</title>
      <link>https://trid.trb.org/View/2239196</link>
      <description><![CDATA[How to select the optimal formulations for building blended physics-machine learning models for ship motions is not currently clear. This work compares and contrasts two approaches to this problem: (1) A black-box deep learning approach based on a new neural network architecture that can better handle varying wave conditions, and (2) a clear-box model based on updates to linear response amplitude operators via a Gaussian process regression. Both models are trained and evaluated on a dataset consisting of more than 15,000 30-minute-long motion observation windows from two research vessels at sea in the Atlantic and Pacific oceans. Three different hindcast weather services are used, including two models from the EU’s Copernicus system and NOAA’s WAVEWATCH III. The evaluation shows that a tradeoff exists between the formulations, with the black-box formulation offering higher accuracy and the cost of less transparency. The weather hindcast used has a small impact on the results, and the ability of both models to generalize predictions between near-sister ships is also encouraging for the practical application of these techniques.]]></description>
      <pubDate>Mon, 16 Oct 2023 17:24:45 GMT</pubDate>
      <guid>https://trid.trb.org/View/2239196</guid>
    </item>
    <item>
      <title>Free roll decay simulation of a polar research vessel with an anti-roll tank based on CFD</title>
      <link>https://trid.trb.org/View/2224722</link>
      <description><![CDATA[The Polar Research Vessel (PRV) must consider both icebreaking and ocean navigation performance, but its hull lines can result in large amplitude roll motion in storms. To address this issue, an anti-roll tank (ART) is fitted to restrain the roll. Using the viscous CFD method, a numerical model is established to couple ship motion with fluid motion in the ART. The simulation accurately captures the fluid motion characteristics in the ART and solves the nonlinearity of fluid motion coupled with roll motion. The study reveals the suppression rule of ART parameters on ship motion and completes the design of ART for polar icebreakers. Investigating the effects of water load, channel height, and installation height of ART on roll motion suppression using an equivalent damping evaluation method provides insight into ART parameter suppression rules on ship motion, facilitating ART design for polar icebreakers.]]></description>
      <pubDate>Wed, 23 Aug 2023 10:14:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/2224722</guid>
    </item>
    <item>
      <title>Experiment and numerical simulation study on resistance performance of the shallow-water seismic survey vessel</title>
      <link>https://trid.trb.org/View/2157202</link>
      <description><![CDATA[In this paper, a new type of shallow-water seismic survey vessel is proposed to solve the problem that the traditional seismic survey vessels cannot satisfy the requirements of the shallow-water marine resources exploration. To reveal the influence of shallow water effect on resistance and flow field, this research is to obtain the resistance and shallow-water characteristics of this shallow-water seismic survey vessel through ship model experiments and numerical methods. Firstly, the ship model experiment predicted the resistance at different speeds in shallow water and obtained the benchmark data to validate numerical methods. Then, the CFD methods were used to calculate the resistance of the ship in deep and shallow water. The numerical results are in good agreement with the experimental results. Finally, this paper provided details of the distribution of wave, pressure and flow fields at different water depth conditions in order to explain the causes of increased resistance in shallow water, providing a reference for the shallow-water seismic survey vessel design.]]></description>
      <pubDate>Tue, 23 May 2023 10:09:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/2157202</guid>
    </item>
    <item>
      <title>On rudder-roll stabilization autopilot based on response models</title>
      <link>https://trid.trb.org/View/2151066</link>
      <description><![CDATA[This study proposes a rudder-roll stabilization (RRS) autopilot by using novel response models developed by Yasukawa and Yoshimura (YY models) since they include the roll-coupling effect. The statistical optimal control theory which used Akaike information criterion (AIC) was used. To verify the proposed RRS autopilot, numerical simulations based were also performed on the onboard monitoring data of a fishery research vessel; the results confirmed its effectiveness for course keeping and roll reduction.]]></description>
      <pubDate>Fri, 21 Apr 2023 09:49:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/2151066</guid>
    </item>
    <item>
      <title>Development and Implementation of a Remote-Control System for an Unmanned Research Small Vessel</title>
      <link>https://trid.trb.org/View/2120044</link>
      <description><![CDATA[The paper presents the results of the development and implementation of a remote-control system for an unmanned research small vessel, consisting of onboard and coastal control subsystems. The developed system was installed and tested on a small vessel manufactured at the Sevastopol State University. The control system allows the navigator to control the vessel at a distance of 1-2 km, to carry out video surveillance of the situation around the vessel, to control the orientation and location of the vessel. Wi-Fi technology is used to connect the coastal and onboard subsystems. Also, the navigator has the opportunity to control the vessel using a portable hand control panel.]]></description>
      <pubDate>Thu, 23 Mar 2023 11:08:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/2120044</guid>
    </item>
    <item>
      <title>An SPH study of slamming and splashing at the bow of SYSU vessel</title>
      <link>https://trid.trb.org/View/2095867</link>
      <description><![CDATA[Operating in extreme sea conditions, vessels often meet horrible wave impact which generates wave breaking and splashing at the bow and poses a great threat to staff safety and structural strength. Characterized with the ticklish issues e.g. multiphase interface and free surface large deformation, the study of slamming and splashing needs more reliable numerical tools. Smoothed particle hydrodynamics (SPH) method, benefiting from its Lagrangian meshless nature, shows superior performance in simulating slamming and splashing properties, which is employed in this paper to model the slamming process of the Sun Yat-sen University (SYSU) scientific research vessel. 2D wedges and 3D hemisphere water-entry benchmarks are simulated to validate the SPH model. After extending 2D to 3D simulation, SPH-based and finite volume method (FVM) -based solvers are exploited with various slamming cases for the SYSU scientific research vessel. Comparisons of the numerical results on dynamic response and bow slamming hydrodynamics of the SYSU vessel between SPH and FVM are performed in this paper. The numerical results demonstrate that except for precise prediction of hull dynamics, SPH is good at tracking the complex interface and splashing details, which possesses practical applicability in the simulation of violent fluid–structure interaction.]]></description>
      <pubDate>Thu, 19 Jan 2023 11:23:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/2095867</guid>
    </item>
    <item>
      <title>Comparison of full-scale measurements and seakeeping calculations for two research vessels in the Adriatic Sea</title>
      <link>https://trid.trb.org/View/2070995</link>
      <description><![CDATA[The paper describes two experimental campaigns of seakeeping measurements for two research vessels in the Adriatic Sea and comparison of the experimental results with the seakeeping calculations. The waves and vessel motions are simultaneously measured at seas. Sea surface elevation of wind waves is measured using a wave buoy, freely floating near the vessel. Measurements of vessel motions are performed using motion sensors mounted on the bridge deck. Measurements are performed for different heading angles between the prevailing wave direction and the vessel. Time signals of the measured waves and resulting heave and pitch motions are treated statistically and subjected to spectral analysis. Wave-induced vessel responses are also calculated by the spectral analysis, employing the 3D panel method for transfer functions. Measured wave spectra are approximated by the standard JONSWAP spectra for that purpose. Statistical properties of the measured and calculated wave-induced motions are then compared. The results of the seakeeping calculations are in fair agreement with the measurements, except for mean zero-crossing period of the responses in following seas, where considerable discrepancies are found.]]></description>
      <pubDate>Fri, 16 Dec 2022 09:41:09 GMT</pubDate>
      <guid>https://trid.trb.org/View/2070995</guid>
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