<rss version="2.0" xmlns:atom="https://www.w3.org/2005/Atom">
  <channel>
    <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+PHBhcmFtIG5hbWU9ImxvY2F0aW9uIiB2YWx1ZT0iMCIgLz48L3BhcmFtcz48ZmlsdGVycz48ZmlsdGVyIGZpZWxkPSJpbmRleHRlcm1zIiB2YWx1ZT0iJnF1b3Q7R3Jhdml0eSB3YXZlcyZxdW90OyIgb3JpZ2luYWxfdmFsdWU9IiZxdW90O0dyYXZpdHkgd2F2ZXMmcXVvdDsiIC8+PC9maWx0ZXJzPjxyYW5nZXMgLz48c29ydHM+PHNvcnQgZmllbGQ9InB1Ymxpc2hlZCIgb3JkZXI9ImRlc2MiIC8+PC9zb3J0cz48cGVyc2lzdHM+PHBlcnNpc3QgbmFtZT0icmFuZ2V0eXBlIiB2YWx1ZT0icHVibGlzaGVkZGF0ZSIgLz48L3BlcnNpc3RzPjwvc2VhcmNoPg==" 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>Influence of large-scale shoal and navigation channel on infragravity-wave oscillations in a harbor</title>
      <link>https://trid.trb.org/View/2706856</link>
      <description><![CDATA[This study investigates the influence of a large-scale offshore shoal and a navigation channel on infragravity (IG) wave oscillations within a harbor using Macun Port as a case study. The non-hydrostatic model SWASH was used to simulate wave fields for two channel schemes, one perpendicular and one parallel to the shoal orientation, at design high and low water levels (DHWL/DLWL). The shoal was found to significantly amplify IG waves through nonlinear energy transfer from short waves, with heights up to 6 times the incident values at DLWL. Channel alignment critically influenced this amplification. The scheme with a channel perpendicular to the shoal orientation reduced IG energy entering the harbor by deepening water (suppressing shallow-water IG wave generation) and altering radiation stress fields by wave refraction (suppressing continued energy transfer from short waves), resulting in wharf-side IG wave heights averaging 63% (DLWL) and 74% (DHWL) lower than in the scheme with a shoal-parallel channel. Harbor resonance modes at periods 10–20 times the incident peak period were more sensitive to shoal effects than longer period modes. This shows that optimizing channel alignment can significantly mitigate shoal-enhanced IG waves and associated harbor resonance, providing insights for port engineering in similar environments.]]></description>
      <pubDate>Tue, 02 Jun 2026 13:56:35 GMT</pubDate>
      <guid>https://trid.trb.org/View/2706856</guid>
    </item>
    <item>
      <title>Control of underwater suspended vehicle to avoid ‘falling deep’ under the influence of internal solitary waves</title>
      <link>https://trid.trb.org/View/2434017</link>
      <description><![CDATA[The interaction between the underwater suspended vehicle and the ISWs at different submergence depth is investigated. When the vehicle is above the pycnocline, the surge motion is dominant. While under the pycnocline, the heave displacement will become more significant. The closer it is to the pycnocline, the more drastic the variations of heave displacement and pitch angle will be. As the heave displacement continues to increase, the vehicle will experience the serious ‘falling deep’ accident. To reduce the occurrence of such situations, different control strategies are applied to the vehicle. The control effect, motion response and hydrodynamic characteristics of the vehicle are explored. The results of the study show that the deflection of the vehicle can be effectively reduced with control. The influences differ significantly when different control parameters are applied. If the control is suitable, the heave displacement of the underwater vehicle can be reduced to nearly zero.]]></description>
      <pubDate>Thu, 31 Oct 2024 16:20:32 GMT</pubDate>
      <guid>https://trid.trb.org/View/2434017</guid>
    </item>
    <item>
      <title>Infragravity waves at the Hambantota port located in the North Indian Ocean</title>
      <link>https://trid.trb.org/View/2210307</link>
      <description><![CDATA[Infragravity (IG) waves are the primary cause of harbor oscillations. The Hambantota port located in the North Indian Ocean is taken as an example to study the IG waves in the vicinity and interior of a complex-shaped real harbor and to reveal the energy transfer of IG waves toward the harbor. The research employs a combination of in-situ wave measurement and numerical simulations conducted using the spectral wave model WAVEWATCH III. The latter could provide a long-term estimation of the level of IG wave energy over a broad geographical region, though it cannot reflect the complex mechanism of IG waves near/at the shore. Results indicate that, at the sensor near the harbor entrance, the free IG wave heights HFIG generally exceeds the bound IG wave height HBIG. However, during energetic sea states (significant wave height HS > 2.5 m in this study), HBIG increases significantly and occasionally exceeds HFIG. The spatial distributions of HS, HBIG, and HFIG indicate that the narrow continental shelf surrounding Sri Lanka has a marginal effect on attenuating swell energy. Consequently, the Hambantota port experiences a substantial impact from both swell and accompanying IG waves. If solely considering the maximum acceptable HS, the downtime for large ships would be greatly underestimated. The process of wave propagation into the harbor enables the energy transfer from bound IG waves to free IG waves that finally excite harbor oscillations. Albeit the tidal range is low, the tidal level has a noteworthy impact on harbor oscillations. The IG spectral density during low tides is generally greater than that during high tides due to the enhanced nonlinear interactions of short waves under low-tide conditions.]]></description>
      <pubDate>Wed, 26 Jul 2023 15:59:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/2210307</guid>
    </item>
    <item>
      <title>Wave transformation due to finite floating elastic plate with abrupt change in bottom topography</title>
      <link>https://trid.trb.org/View/2014684</link>
      <description><![CDATA[The propagation of surface gravity waves in the presence of finite floating elastic plate over varying sea bottom profile is investigated using the Timoshenko-Mindlin plate theory. The continuity of velocity and pressure at the interfaces along with the continuity of deflection, slope, bending moment and shear force is employed with the support conditions at the plate edges. The numerical computation is performed to obtain the hydroelastic behaviour of the floating elastic plate due to abrupt change in bottom topography. The validation of the present analytical model is performed with the known results available in the literatures. Further, a detailed comparison of the numerical results is presented for different step bottom topography on the hydroelastic characteristics of a floating elastic platform. The present study will provide an insight into the effect of the ocean bottom profile on wave propagation due to the presence of a large floating elastic plate.]]></description>
      <pubDate>Wed, 30 Nov 2022 10:59:53 GMT</pubDate>
      <guid>https://trid.trb.org/View/2014684</guid>
    </item>
    <item>
      <title>The influence of infragravity waves, wind, and basin resonance on vessel movements and related downtime at the Outer Port of Punta Langosteira, Spain</title>
      <link>https://trid.trb.org/View/2041295</link>
      <description><![CDATA[The coupling of low-frequency oscillatory modes of a harbor with horizontal motions of moored ships can amplify the latter, causing operational and safety problems. The objectives of this study were to analyze infragravity waves and their effect on moored ship motions; to validate the Wavelet Transform Analysis (WTA) method for studying port-ship resonance in the Outer Port of Punta Langosteira, Spain; and to study the climatic forcing of downtimes. The excited resonant modes of the basin (102 and 132 s) were determined using a numerical model and high-frequency water level measurements at different points of the harbor. Yaw and sway motions of three bulk carriers were analyzed in the frequency-time domain using WTA. The results showed that the oscillation periods of the studied vessel motions are directly related to the water depth to vessel draft ratio. In addition, when the wind speeds exceeds 20 km/h, the ship moves away from the fenders, which lead to a lengthening of these periods. Based on the authors' findings, yaw may induce oscillations of the same period in sway. Additionally, operational thresholds were proposed based on outer and inner waves data that will lead to optimize ship stays, avoiding downtimes, and to advance the safety of loading and unloading operations.]]></description>
      <pubDate>Thu, 27 Oct 2022 13:46:58 GMT</pubDate>
      <guid>https://trid.trb.org/View/2041295</guid>
    </item>
    <item>
      <title>Water wave scattering by floating flexible porous plate over variable bathymetry regions</title>
      <link>https://trid.trb.org/View/1727726</link>
      <description><![CDATA[The study deals with the scattering of obliquely incident gravity waves by a horizontal floating flexible porous plate in the water of finite depth having a variable bottom bed. The problem when a vertical rigid wall is placed in the downstream of the plate is also considered. The problem is analyzed under the assumptions of small amplitude water wave theory and structural responses. The undulated bottom bed is finitely extended and lies beneath the floating plate regions. A coupled eigenfunction expansion - boundary element method is used for the solution purpose. Energy balance relations for wave scattering in the presence of the flexible plate and when the vertical rigid wall is placed in the downstream are derived and used to check the accuracy of the numerical results. The effect of sinusoidally varying bottom topography, plate porosity and heading angle of the incident wave on the Bragg resonance is analyzed. Moreover, various results are computed and analyzed to study the role of the wave parameters, bottom undulation and floating porous flexible plate on wave scattering. The proposed solution methodology can be easily extended to deal with wave-structure interaction problems of varied structural configurations and bottom bed.]]></description>
      <pubDate>Wed, 21 Oct 2020 09:52:35 GMT</pubDate>
      <guid>https://trid.trb.org/View/1727726</guid>
    </item>
    <item>
      <title>Wave Attenuation Through Pancake Ice. Measurements From a Moving Vessel in the Barents Sea in 2017</title>
      <link>https://trid.trb.org/View/1717818</link>
      <description><![CDATA[The knowledge about attenuation of gravitational waves in ice can be useful for offshore operations conducted in the vicinity of marginal ice zones. The length and type of ice of the marginal ice zone can vary by region and ocean conditions. There are several studies conducted in different ice condition describing attenuation of waves in ice. In this work, an absolute orientation IMU sensor was built based on open-sourced hardware and software, and it was used to obtain waves attenuation coefficients in thin, small-size pancake ice floes. The study was performed during an educational expedition of the arctic technology department at the University Centre in Svalbard. M/S Polarsyssel, the ship of the governor of Svalbard, was used 22-30 April 2017 to conduct the expedition. Wave attenuation was estimated by measuring heave response of the vessel, while it was transitioning towards ice edge across Spitsbergenbanken, the area between Hopen Island and Bjørnøya Island. A range of attenuation coefficients 0.1×10⁻¹– 0.3×10⁻⁴ m⁻¹ was obtained for the corresponding range of wave spectra 0.1 – 0.2 Hz.]]></description>
      <pubDate>Wed, 15 Jul 2020 09:12:12 GMT</pubDate>
      <guid>https://trid.trb.org/View/1717818</guid>
    </item>
    <item>
      <title>Measuring Sea Surface Gravity Waves Using Smartphones</title>
      <link>https://trid.trb.org/View/1650879</link>
      <description><![CDATA[Typical oceanographic instruments are expensive, specifically designed for a specific proposed, hard to deploy, and requires constant and specialised maintenance. However, here the authors present a simplified technique for measuring the 4-dimensional sea surface elevation (x, y, z, t) in space and time based on a low-cost stereo-video system using smartphones. The system is easy to deploy and mainly requires a fixed platform close to the sea. The time records are mostly limited by the equipment storage limit and battery life, although it can be easily replaced or recharged. In this work,the authors define the key points for this reconstruction and discuss its capabilities and limitations. They illustrate the application of the stereo video by smartphones-system by a beach experiment in the Southeast Brazilian coast.]]></description>
      <pubDate>Fri, 28 Feb 2020 10:12:13 GMT</pubDate>
      <guid>https://trid.trb.org/View/1650879</guid>
    </item>
    <item>
      <title>High Frequency Gravitational Waves - Induced Propulsion</title>
      <link>https://trid.trb.org/View/1560310</link>
      <description><![CDATA[It may be possible to generate high power / high frequency gravitational waves (HFGWs) by high frequency accelerated axial rotation (spin) and/or accelerated high frequency vibration of an electrically charged, possibly asymmetric structure, within the context of non-equilibrium thermodynamics, namely far-from-equilibrium physics, highly non-linear in nature.         The structure which is the HFGW generator (HFGWG), has the ability to control the accelerated modes of vibration and spin of its electrically charged surfaces, in particular the rapid rates of change of accelerated-decelerated-accelerated vibration and/or accelerated-decelerated-accelerated gyration (axial spin) of these electrified surfaces, in this manner delaying the onset of relaxation to thermodynamic equilibrium, thus generating a physical mechanism which may induce anomalous effects. Under certain conditions, involving rapid acceleration transients, it is observed that there will be exponential growth in electromagnetic energy flux with accelerating vibration. In the present paper, high power HFGWs are generated by enabling the Gertsenshtein effect, that is gravitational wave production by propagating electromagnetic radiation through strong magnetic fields.         Controlled motion of charged matter under rapid acceleration transients may enable macroscopic quantum coherence, namely possible quantum mechanical behavior of macroscopic objects. Moreover, the accelerated vibration and/or spin of charged matter may generate high power / high frequency gravitational waves which can be used in a variety of applications, such as advanced field propulsion, namely the design of a workable space drive.         Therefore, it may be feasible to propel a hybrid craft equipped with an HFGWG, by producing high frequency gravitational waves which in turn generate their own gravitational fields upon which the craft would propagate in a ‘wave-surfing’ fashion.       ]]></description>
      <pubDate>Tue, 18 Feb 2020 10:14:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/1560310</guid>
    </item>
    <item>
      <title>Infragravity Seiches in a Small Harbor</title>
      <link>https://trid.trb.org/View/1474072</link>
      <description><![CDATA[A method is developed to estimate harbor seiche at Marina di Carrara, Italy, from the properties of wind-generated incident waves outside the harbor. A linear model of the spatial structure of amplified seiche modes is combined with empirical estimates of the response of each mode to variable incident wave forcing. These empirical coefficients parameterize the complex nonlinear transfer of energy from wind waves to lower frequency seiche. As at other small harbors (<1 km2 surface area) on ocean coasts, and consistent with previous analyses at Carrara, the observed seiche is relatively energetic at several periods between about 1 and 15 min that are highly amplified theoretically, and the spatial structure of modeled and observed seiches agree as well. The longest seiche (≈15 min) mode is almost spatially uniform within the harbor and dominates with low-energy, short-period incident wind waves (measured 1 km offshore of the harbor). Increased wave energy and longer periods excite shorter period (1–3 min) seiche modes with more complex spatial structure, including small areas of high amplification, which have led to operational issues. The energy in each of the six most energetic seiche modes is related in this paper empirically to offshore incident wind wave height and peak period, allowing detailed predictions of harbor seiche from routine wind wave forecasts. The approach appears applicable to relatively small, shallow harbors with reflective quay walls, in which the exterior harbor mouth is exposed, and the interior sheltered from energetic wind-generated waves.]]></description>
      <pubDate>Thu, 27 Jul 2017 10:05:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/1474072</guid>
    </item>
    <item>
      <title>Numerical and Experimental Studies on the Propulsion Performance of a Wave Glide Propulsor</title>
      <link>https://trid.trb.org/View/1426546</link>
      <description><![CDATA[This paper introduces a newly developed Unmanned Wave Glide Vehicle (UWGV), which is driven only by extracting energy from gravity waves, and presents a comprehensive study on the propulsion performance of the UWGV’s propulsor―Wave Glide Propulsor (WGP) in a regular wave. By simplifying the WGP as six two-dimensional (2D) tandem asynchronous flapping foils (TAFFs), a computational fluid dynamics (CFD) method based on Navier-Stokes equations was first used to analyze the hydrodynamic performance of TAFFs with different parameters of non-dimensional wave length m and non-dimensional wave height n. Then, a series of hydrodynamic experiments were performed. The computational results agree well with the experimental results when n≤0.07 and both of them show the thrust force and input power of the WGP are larger at smaller m or larger n. By analyzing the flow field of TAFFs, the authors can see that a larger m is beneficial to the forming, merging and shredding of the TAFFs’ vortices; as TAFFs are arranged in tandem and have the same motions, the leading edge vortex and wake vortex of the TAFFs are meaningful for improving the thrust force of their adjacent ones.]]></description>
      <pubDate>Tue, 25 Oct 2016 10:00:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/1426546</guid>
    </item>
    <item>
      <title>Experimental Study on the Performance of a Wave Pump for Artificial Upwelling</title>
      <link>https://trid.trb.org/View/1398052</link>
      <description><![CDATA[When surface gravity waves propagate past a rigid open-ended pipe, there is a negative pressure at the upper end of the pipe. Recently it has been suggested to be used as a wave pump for artificial upwelling. This paper presents experiments and theoretical analysis to obtain the performance of the wave pump in regular waves. Experiments are performed in a wave tank at different density difference heads, wave amplitudes and frequencies with four different pipe diameters. A theoretical model is proposed taking into account the flow characteristics of artificial upwelling. The performance of the model has been confirmed by the experimental findings. The present results show that the pump capacity and efficiency are functions of the wave amplitude and frequency, geometrical parameters of the pipe and vertical distribution of water density. An upwelling flow of 5–360 m3/h can be generated by the wave pump under a wide range of wave conditions. Moreover, the pumped water flow rate and upwelling efficiency can be increased by optimizing the distance between the upper end of the pipe and the trough of the wave, and increasing the pipe diameter. Further work will have to determine the performance of the wave pump in random waves.]]></description>
      <pubDate>Thu, 24 Mar 2016 10:51:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/1398052</guid>
    </item>
    <item>
      <title>Stokes drift estimation based on long-term variation of wave conditions</title>
      <link>https://trid.trb.org/View/1352434</link>
      <description><![CDATA[This article provides a simple analytical method which can be used to give estimates of the Stokes drift based on long-term variation of wave conditions. This is achieved by providing bivariate distributions of significant wave height with surface Stokes drift as well as with volume Stokes transport. These Stokes drift parameters are defined in terms of significant wave height and characteristic wave periods. This article presents the mean value and the standard deviation of these Stokes drift parameters, that is, more precisely the conditional expected values and the conditional variances for given significant wave height, as well as examples of results corresponding to typical field conditions. Based on, for example, global wave statistics, the present analytical results can be used to make estimates of the Stokes drift.]]></description>
      <pubDate>Fri, 22 May 2015 16:14:09 GMT</pubDate>
      <guid>https://trid.trb.org/View/1352434</guid>
    </item>
    <item>
      <title>Observations of infragravity period oscillations in a small marina</title>
      <link>https://trid.trb.org/View/1320307</link>
      <description><![CDATA[The authors measured water levels in Two Rocks Marina, Western Australia, to investigate infragravity-period (25–300 s) oscillations and their forcing mechanisms. Spectral analyses identified four dominant oscillations in the infragravity band, which were generated through excitation of the marina’s natural periods. The oscillations were present at all times, independent of the offshore conditions, indicating that they were forced by a continuous external energy source. The spectral energy of the oscillations increased by ~50 times during storm events (higher incident wave heights), in comparison to calm events (lower incident wave heights). Wave heights of oscillations within the marina were strongly correlated with offshore incident swell wave heights and reached maximum of 0.5 m. The groupiness factor of swell waves around the marina was 0.6–0.85. Bound infragravity waves associated with swell wave groups were identified as potential forcing mechanism of infragravity-period oscillations within the marina. The bound infragravity waves have broad frequency spectrum without dominant periods matched the marina’s natural periods however, bound infragravity waves of periods in the proximity of the marina NOPs were adequate to generate oscillations at the NOPs of the marina. Frequencies of the oscillations were independent of the forcing frequency, and determined by the marina's geometry.]]></description>
      <pubDate>Wed, 20 Aug 2014 15:36:59 GMT</pubDate>
      <guid>https://trid.trb.org/View/1320307</guid>
    </item>
    <item>
      <title>Surface gravity wave interaction with circular flexible structures</title>
      <link>https://trid.trb.org/View/1320308</link>
      <description><![CDATA[Surface gravity wave interaction with circular floating elastic plates of finite radius is analyzed in both the cases of single and two-layer fluids in finite water depth. The problems are analyzed under the assumption of small amplitude water wave theory and structural response. Further, gravity wave diffraction by circular elastic plates is studied under shallow water approximation based on linearized long wave theory. In the present analysis, the flexible structures are namely flexible circular plates and membranes of negligible draft. From the general formulation of the floating elastic plates, the results associated with the flexible membranes are obtained as special cases. Fourier–Bessel series type expansion formulae for the velocity potentials are obtained in the open water surface region and flexible plate/membrane covered region by the method of separation of variables. Suitable orthogonal mode-coupling relations are used along with the matching of velocity and pressure to obtain system of equations for the determination of the unknowns in the expansion formulae. Numerical results on structural deflection are computed and plotted to understand the hydrodynamic characteristics of the floating structures under water action. In order to understand the flow distribution around the floating circular flexible structures, contour plots are provided.]]></description>
      <pubDate>Wed, 20 Aug 2014 15:36:57 GMT</pubDate>
      <guid>https://trid.trb.org/View/1320308</guid>
    </item>
  </channel>
</rss>