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    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <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>
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      <link>https://trid.trb.org/</link>
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    <item>
      <title>Autonomous Route Planning for Ships in Complex Waterways</title>
      <link>https://trid.trb.org/View/1974456</link>
      <description><![CDATA[Route planning for ship navigation is a process to generate the optimal route with the careful consideration of ship maneuvering constraints and environmental conditions. This paper presents a study on a ship’s navigation through a canal estuary area with the strong currents. An autonomous route planning algorithm based on the modified RRT approach (rapidly-exploring random tree) is developed to handle this increased level of complexity. A series of navigation model tests were conducted to verify this route planning algorithm. The optimal route generated from the proposed algorithm could ensure safe navigation of the ship model through this canal estuary area without any collisions with the dikes or the tidal barrier. Autonomous route planning built upon scientific theories and operational experiences has the great advantage to generate optimal routes even in complex waterways, which is possible to minimize human errors in navigation decision.]]></description>
      <pubDate>Fri, 06 Sep 2024 09:27:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974456</guid>
    </item>
    <item>
      <title>Sustainability Assessment of Small Scale Fishing Vessel Operations: A Case Study in Palabuhanratu, Indonesia</title>
      <link>https://trid.trb.org/View/1974446</link>
      <description><![CDATA[The important factor in promoting sustainable fisheries is implementing a sustainable fishing operation that is not only environmentally friendly but also economically and socially acceptable. As most of the existing improvement focused on the fishing gear, this study concentrates on the fishing vessel. Investigation on the existing practices is a key to formulation of management measures, hence a sustainability assessment has been carried out on small-scale fishing vessels by incorporating environmental and economic aspect of fishing operations. A case study was conducted in Palabuhanratu, a region with a significant number of small-scale fishing practices, which is typical of many fishing regions in Indonesia and other developing nations. Assessment was conducted on four principal types of vessels representing pelagic-ground fishing and active–passive fishing. Amongst the studied vessels, the lift net vessel which operates pelagic-passive fishing generates the least impact in both environmental and economic indicators, whilst the largest impact is derived from the trammel net vessel. In general, passive fishing has better performance in comparison to active fishing. Compared to pelagic fishing, ground fishing contributes higher impacts on environment, however in terms of economic, this operation catches more valuable fish than its counterpart. This result suggests the importance of trade-off when formulating management measures to promote the sustainable fishing vessel operations.]]></description>
      <pubDate>Fri, 06 Sep 2024 09:27:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974446</guid>
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    <item>
      <title>Development of Basic Planning Support System Using Marine Logistics Big Data and Its Application to Ship Basic Planning</title>
      <link>https://trid.trb.org/View/1974443</link>
      <description><![CDATA[Recently, the utilization of big data has been conducted in various sectors. Big data is a large collection of datasets that is effective for understanding current situations and future development. In marine industries, big data in the form of automatic identification system (AIS) data, ship principal dimension, port facilities, shipping routes, and international trade data has increased significantly. It is possible to acquire the insights of shipping industry activities with the effective utilization of big data. Similarly, the dynamic situation of the global market requires aggressive ship development. Accordingly, it is critical to realize certain ship specifications to satisfy market requirements. Considering this background, the authors examined the utilization of marine logistics big data to support ship basic planning, and developed a ship basic planning support system that can predict the demand of ships using marine logistic big data. However, in a previous study, a methodology to generate effective information using big data was the focus, and the applicability to practical ship design was not examined. Herein, the applicability of the ship basic planning support system to practical ship design is examined. Hence, the reliability of marine logistics big data (such as AIS data and ship movement data) according to region are examined. Moreover, a ship allocation model is developed in conformity with a marine logistic database. Applying a ship allocation model, the authors can reproduce the actual ship allocation of targeted shipping conditions and predict ships with high future demand. Therefore, effective ship size, ship performance, and ship demand are examined by assuming some future scenarios using the developed system, and some examples are presented.]]></description>
      <pubDate>Fri, 06 Sep 2024 09:27:50 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974443</guid>
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    <item>
      <title>A Simplified Nonlinear Analysis Procedure for the Flexible Risers in Subjected to Combined Loading Effects</title>
      <link>https://trid.trb.org/View/1974404</link>
      <description><![CDATA[A dynamic analysis of flexible risers in large-scale domain remains the offshore industry’s most challenging problems. The cross section of flexible risers, consisting of multiple metallic and plastic layers, experiences inter-layer slippage during cyclic bending. This results in nonlinear and hysteretic bending behavior with rapid dissipation of energy. For the dynamic analysis for flexible risers in the large scale domain, this study replaces all layers of risers with simple beam elements with a nonlinear beam model. This simplified beam model traces the curvature to bending moment relation and captures the variation of stiffness due to the onset of slippage. The suggested methods formulate both the change of configuration due to large deflection and contact between risers and seabed, therefore more realistic and effective analysis can be achieved. In the current study, the details of the analysis method are described. Main formulation methods of the total Lagrangian framework and the interaction between risers and seabed are described as well as the nonlinear bending model for flexible risers. The validity of the developed method is examined through some case studies, and the results show how the bending nonlinearity of flexible risers affects the overall behavior of riser systems during its operation.]]></description>
      <pubDate>Thu, 05 Sep 2024 10:24:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974404</guid>
    </item>
    <item>
      <title>Study on Motion Response of a Floating Offshore Turbines’ Unit with OWC</title>
      <link>https://trid.trb.org/View/1974399</link>
      <description><![CDATA[Recently the problem of the global warming rises an importance of using the renewable energy. Wind energy is recognized as one of the key sustainable energy source. In fact, there are rapidly increase the number of a wind power plant in land and now the power plant extends to offshore area. Therefore, a floating offshore wind turbine (FOWT) system which can be applied to various sea area is attracted. One of the problem is that FOWT must oscillate in waves. Generally, the FOWT system is horizontal axis system as same as those in land, however, the motion of FOWT in waves causes relatively large acceleration at a nacelle. And it is concerned that the acceleration disturbs the maintenance work. Because the vertical axis type FOWT has a nacelle, which many of the mechanical system is in, set near the water level though its efficiency in aerodynamics has disadvantage, it is possible that the maintenance work will be easier. The authors has proposed a concept of twin vertical axis type FOWT. In our past experiment we have confirmed that the twin system can cancel a gyro moments induced by each rotation and the suitable distance of the twin turbine increases the rotational speed of the turbine than the single turbine. On the other hand, the shape of the underwater structure making the needed buoyancy and reducing the passive external hydrodynamic force has relatively small stability inducing acceptable but relatively large pitch motion in waves. So, to reduce the pitch motion while generating the electrical energy, we propose a new concept of a floating offshore twin vertical axis turbines system with oscillated water columns (OWCs). The OWC is one of the type of wave energy converter (WEC).]]></description>
      <pubDate>Thu, 05 Sep 2024 10:24:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974399</guid>
    </item>
    <item>
      <title>A Study of Riser Oscillations Caused by Slug Flows During Subsea Petroleum Production</title>
      <link>https://trid.trb.org/View/1974396</link>
      <description><![CDATA[The theoretical influence of the internal slug flows on the motion of suspended slender pipes is presented here through two examples of computer simulations applied to two types of risers employed in offshore petroleum production – a steel catenary riser (SCR) and a steel lazy wave riser (SLWR) hanging from a floating platform. The results presented here provide strong evidence that slug flows may induce hazardous oscillation, even in the absence of other excitations. The exploitation of hydrocarbons from underground reservoirs in open sea is undertaken amidst very adverse environmental conditions, below ultra deep waters and usually very deep reservoirs, as in the pre-salt and carbonate formations discovered in the Brazilian southeast Atlantic coast basin. In this scenario, large production rates of oil and gas are required to achieve economically feasible operations; which means successfully maintaining an uninterrupted flow of reservoir fluids under safe conditions from many subsea wells. The multiphase petroleum flowing from the wellhead at the sea bottom to the floating process facility at the sea surface is conducted by lengthy pipelines lying on the seabed up to the point where the flow ascends to the sea level through very long and slender pipes – named risers – suspended by its top end at the floating production unit. Risers may be flexible or made from steel rigid pipes and are often subjected to sea current and wave loads and to the movements of its supporting ship or platform, which are dangerous to the pipe integrity. Risers are also excited to oscillate due to the multiphase flow inside them. It is of paramount importance to understand and determine the dynamic behavior of the suspended pipes due to those loads, in order to achieve a service life as extensive as economically possible. The method employed in the present research consists of modifying a computer dynamic simulator of pipeline movement, adding the internal fluid loads arising due to the weight and momentum of the flowing masses of liquid and gas. The simulations show that a steady slug flow may alone produce oscillatory displacements of the riser of rather significant amplitudes, without any other external cause; particularly when the slug’s excitation is near the natural frequencies of the riser. The results indicate that the oscillations are strongly dependent on the slug frequency. The modified simulator is flexible enough to compute the effect of a wide range of slugs’ configurations (geometry, fluids, flow rates etc.), allowing the analysis of fatigue damage and risk of failure under many production conditions.]]></description>
      <pubDate>Thu, 05 Sep 2024 10:24:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974396</guid>
    </item>
    <item>
      <title>Optimizing Ships Using the Holistic Accelerated Concept Design Methodology</title>
      <link>https://trid.trb.org/View/1974393</link>
      <description><![CDATA[The holistic accelerated concept design optimization method is a new method to optimize ships in an efficient way. This optimization method is developed to automatically check feasibility and at the same time optimize ships by generating different design variations. The naval architect uses his creativity and imagination to develop a parametric three-dimensional ship model which can then be checked and optimized by automated software. This way, the naval architect can focus on the innovative and creative aspects of ship design while repetitive labor intensive tasks can be executed by the computer. It is shown in this paper that the holistic design optimization method leads to improved design variations in a short amount of time.]]></description>
      <pubDate>Thu, 05 Sep 2024 10:24:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974393</guid>
    </item>
    <item>
      <title>Communication of Design Space Relationships Learned by Bayesian Networks</title>
      <link>https://trid.trb.org/View/1974389</link>
      <description><![CDATA[Modern ship design often involves the automated creation of thousands of design alternatives; even when provided a Pareto front of optimal solutions designers may struggle to understand the differences in designs and the relationships of design variables. Machine learning Bayesian networks from automatically developed design data can allow us to analyze the designs, understand the variable relationships that drive their differences and optimalities, and lead engineers to better designs. However, the information about variable relationships in Bayesian network are encoded in difficult to interpret conditional probability tables (CPTs). Translation of a Bayesian network’s CPTs into simpler edge weights defining the strength of relationship between nodes allows engineers to more easily interpret and use the complex information encoded in the network through standard network analysis techniques. Bayesian networks developed from a multi-objective bulk carrier design problem developed by Sen are transformed to network adjacency matrices for such analysis in this work.]]></description>
      <pubDate>Thu, 05 Sep 2024 10:24:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974389</guid>
    </item>
    <item>
      <title>“Monitoring Platform” of Monitoring and Visualizing System for Shipyard: Application to Cutting and Subassembly Processes</title>
      <link>https://trid.trb.org/View/1974385</link>
      <description><![CDATA[Owing to the rapid progress of information and communication technology (ICT), a new manufacturing environment that utilizes the ICT infrastructure effectively is expected, and various activities are performed proactively worldwide. This activity is positioned as the Fourth Industrial Revolution (Industrie 4.0) by the information network and is attracting worldwide attention. Even in the shipbuilding industry, the realization of Industrie 4.0 by IoT (Internet of Things) is important. The cyber–physical system (CPS) is the core concept to realize Industrie 4.0; further, it is important to realize the cyber ​system (virtual world) that constitutes this CPS and the “factory visualization system” technology. In this application, we will develop a foundation necessary for developing the monitoring/visualizing system for shipyards based on the factory visualization system and enhance the quality of data obtained by the visualization system. In this study, this foundation is used for developing the “monitoring platform” and will be applied to the actual process of a shipbuilding factory to evaluate its effectiveness. In the factory visualization system that is the base of this research and development, monitoring information is acquired primarily on the image analysis technology of video images. In this research, we add functions to acquire more monitoring information from the video image and develop an additional function of the foundation for developing the monitoring platform. To acquire the level of monitoring information available at the actual factory, we aim to improve both the accuracy and processing speed of image analysis and expand the target area of image analysis. A monitoring platform to develop a visualization system is necessary to realize Industrie 4.0 for shipbuilding. In this study, we organized and implemented additional functions for developing a visualization system of the cutting and subassembly processes and verified the practicality of the monitoring platform.]]></description>
      <pubDate>Thu, 05 Sep 2024 10:24:01 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974385</guid>
    </item>
    <item>
      <title>On the Development of the Arc7 LNG Carrier – Hull Form Development</title>
      <link>https://trid.trb.org/View/1974382</link>
      <description><![CDATA[This paper focuses on the brief history and some fundamental technical issues which are raised during the hydrodynamic design development of DSME Arctic LNG carrier for Yamal area. In 2010, DSME investigates ship design concept and economic aspects for shuttle LNG transportation services from Yamal peninsula to Murmansk. In this study, Arc7 class 85,000 m³ shuttle LNG carrier which is driven by twin pod propulsion system has been developed. The economic evaluation for round trip with three bow design alternatives (bulbous bow, moderate ice bow and extreme ice bow) have been made and found that the extreme type of bow variant can transport the highest annual volume of cargo. The design development for 170,000 m³ class Arctic LNG carrier was undertaken early in 2011. Various types of bow including bulbous bow type were compared based on the model tests and, the performance comparison between different propulsion concepts. After the newbuilding contract for Yamal LNG in 2013, a set of challenging target for open water speed performance and ice capabilities are given. In order to comply with the target, a hull form optimization using utmost advanced CAE technologies were carried out considering multi-operation profiles, i.e. laden and ballast draft conditions including speed variations. In addition to the optimization for conventional open water, bow and specially designed stern shapes are also optimized in view point of ice breaking abilities by applying the constraints of hull form characteristics to maintain the target ice capabilities. And those full scale open water and ice breaking performances are finally well confirmed in official sea trials and ice trial.]]></description>
      <pubDate>Thu, 05 Sep 2024 10:24:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974382</guid>
    </item>
    <item>
      <title>Hydrodynamic Analysis of Offshore Aquaculture Platform and Its Mooring Design</title>
      <link>https://trid.trb.org/View/1974381</link>
      <description><![CDATA[Offshore aquaculture platforms, or fish cages, are increasingly becoming popular in recent years in the effort of meeting the world’s demand for seafood products. As a result, these platforms are being deployed further offshore in order to avoid causing pollution to near shore waters by densely populated platforms. On the other hand, the dimensions of the platforms are also becoming larger, reaching over 100 m in diameter in the recent designs. As the aquaculture platforms are typically of frame type structures consisting of slender beams which support the net around the frame, the hydrodynamic properties of the platform is quite complex and yet is very important to the adequate design of the platform and its mooring system as any significant under design or over design of the platform and mooring system can incur serious economic consequences. In this paper, a method based on the conventional potential flow theory and Morison equation is proposed for the assessment of the hydrodynamic loads on the aquaculture platforms including its frame and net. This method can take into account the sheltering effect due to the surrounding net or beams but neglects the energy dissipation due to the viscosity of the fluid. A Morison model for an aquaculture platform is constructed and a mooring system is designed in this paper followed by the time domain analysis to assess the hydrodynamic forces, motion responses and mooring system performance in various environmental conditions. The numerical results indicate that the motion of the platform and the mooring tension can meet the design requirements in survival environmental conditions, and the proposed method provides a useful and efficient tool for the evaluation of the performances of the aquaculture platforms.]]></description>
      <pubDate>Thu, 05 Sep 2024 10:24:00 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974381</guid>
    </item>
    <item>
      <title>Development and Design of a Floating Type Ocean Current Turbine System</title>
      <link>https://trid.trb.org/View/1974380</link>
      <description><![CDATA[Ocean currents are expected as future renewable energy resources. Recently various ideas are studied all over the world to utilize the power of this ocean current for generation of electricity. Application of various types of turbines has been proposed for this purpose, but very little examples have been reported with regard to actual demonstration in the natural ocean current environment.The Kuroshio Current which flows through near Japan coast is one of the strongest ocean currents in the world. To utilize this plentiful energy, we developed the floating type ocean current turbine system “KAIRYU” under the support of NEDO (New Energy and Industrial Technology Development Organization), and we completed the 100 kW order turbine demonstration test in the natural Kuroshio Current.In this paper, we report design methodologies and the results of the test. Especially we focus on the structural design to enable stable flotation in the water, the control of weight distribution and the center of flotation for balance, and the pressure-resistant design of the shell structure to secure water-tightness in the deep sea.]]></description>
      <pubDate>Fri, 30 Aug 2024 16:58:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974380</guid>
    </item>
    <item>
      <title>Experimental and Numerical Comparisons of a Floating Absorber Wave Energy Converter in Regular Waves</title>
      <link>https://trid.trb.org/View/1974378</link>
      <description><![CDATA[One of main problems of wave energy development is high cost of devices development. Thus the time required to simulate these devices with Computational Fluid Dynamics difficulty the early stages of design process. In this paper the used of simplificated numerical models are used to reduce this time in presented.The aim of this paper, is the comparison and validation of floating absorber of wave energy, between open source software simulations, based in potential theory and tests in a wave tank.Therefore, in the presented cases mathematical models in frequency domain have been computed through Nemoh to obtain the hydrodynamic coefficients, (added mass and damping matrix) and these coefficients are included in BEMIO and WEC-Sim, which execute numerical model in time domain, to tests simulation.]]></description>
      <pubDate>Fri, 30 Aug 2024 15:53:02 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974378</guid>
    </item>
    <item>
      <title>Nonlinear Wave Loads on Deep-Water Semisubmersibles</title>
      <link>https://trid.trb.org/View/1974379</link>
      <description><![CDATA[Among various types of offshore drilling rigs, the semisubmersible platform is the most popular one for the mid and deep-water exploration activities thanks to its good motion characteristics. With the oil exploration activities moving into deeper water and variable deck load capacity growing, the size of semisubmersible units has increased significantly. Because of the increased usage of these large units in harsh environments, the prediction of the extreme wave loads has become more important. The critical responses of the large semisubmersibles include the longitudinal shear force between pontoons, the split force between pontoons, and torsional moment. For these giant deep-water units, the traditional linear analysis overestimates the wave loads, which leads to a substantial increase of the lightship weight and hence the cost of the rig. In this paper, we compare the experimental and linear numerical results of the wave loads of a 7th generation deep-water semisubmersible drilling unit. The linear numerical calculation uses a three-dimensional panel method in the frequency domain. The important findings in this paper are: 1. The wave loads measured in the model tests were 10 to 15% less than the linear analysis, and the torsional moment showed a maximum difference as about 30%. This result indicates potentials of a substantial reduction of the lightship weight by using nonlinear analysis. 2. The linear and nonlinear results also showed different characteristics to different wave directions in some cases. This difference will affect the selection of the critical design wave and thus influence the global structural analysis and the design of the platform.]]></description>
      <pubDate>Fri, 30 Aug 2024 15:53:02 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974379</guid>
    </item>
    <item>
      <title>Real Time Estimation of Local Wave Characteristics from Ship Motions Using Artificial Neural Networks</title>
      <link>https://trid.trb.org/View/1974377</link>
      <description><![CDATA[Wave characteristics such as significant wave height, peak period and main direction have an important effect on all aspects of ship operations. Yet, estimation of these characteristics in real time in an accurate, robust and efficient manner poses a significant challenge. Current approaches include using wave buoys, wave radars, weather forecasts and regression based on ship motion statistics. External sources are not always available or reliable, and wave radars are expensive. Statistics based methods work reasonably well for wave height, but fail to estimate peak period and relative wave direction. In this study the attention is focused on estimating the wave characteristics from ship motions using artificial neural networks. The inputs to the neural networks were the time histories of 6-DOF ship motions, and the outputs were the wave characteristics. Using time series instead of statistics preserves phase differences between signals. Especially when estimating the relative wave direction, these phase differences encode essential features. Therefore, the problem was treated as multivariate time series regression. Two different data sources were used with neural networks: in-service measurement data and numerical simulation data. In-service measurement data was collected from a frigate type vessel for a period of two years. The numerical simulation data was produced by using a time-domain seakeeping and manoeuvring software. In this paper, we present methods to successfully implement neural networks for real time estimation of local wave characteristics. The paper will include details about the measurement data, numerical simulations, the networks architectures and their performances on the measurement and simulation data.]]></description>
      <pubDate>Fri, 30 Aug 2024 15:53:02 GMT</pubDate>
      <guid>https://trid.trb.org/View/1974377</guid>
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