bluuebunny/crossref_metadata_2025_split huggingface dataset:
ISM-Based Study on the Constraints of Yangtze River Mainline Fleet Transportation Development in the Context of Green Intelligence
Authors: Yang Yinhua , Jin Yan 
Published: October 2022

Abstract
To explore the applicability of the explanatory structure model in the analysis of the water transportation system, the study of fleet development constraints of the Yangtze River mainline is studied as an example. Based on defining the fleet transportation system boundary and summarizing each influencing factor, the standard ISM deconstruction method is used to obtain the hierarchical relationship among the influencing factors. The structural hierarchical relationship of the constraints to the development of fleet transportation on the Yangtze River mainline is analyzed, and the root factors that restrict its development are found to be: fleet size and new logistics pattern. The results show that the explanatory structure model can better analyze the hierarchical relationship between the factors of the water transportation system. Based on this, and in the context of the current major strategic decision of “carbon peak, carbon-neutral”, the paper finally proposes a new fleet transportation mode combining single vessel and fleet characteristics as a solution to the root causes, which can be an efficient and green transportation option for the Yangtze River mainline cargo transportation market.
Numerical Simulation of a Subsea Pipeline Subjected to Near-Field Underwater Explosion Loads With the Coupled Eulerian-Lagrangian (CEL) Method
Authors: Liu Zhenhui , Igland Ragnar 
Published: October 2022

Abstract
An underwater unexploded ordnance (UXO) for example a mine filled with trinitrotoluene (also known as TNT), may present a potential threat to subsea structures. An explosion is a complicated physical phenomenon as it involves the interactions among water, seabed, the structure, and the explosive ordnance. The relevance of the paper is the need for removal of a large number of UXO on the Norwegian continental shelf during the installation of subsea pipelines. Numerical simulations have been used to calculate the effect of an explosion, but normally with an assumption of free explosion space. The seabed effects are simply considered by exaggerating the explosive weight with an empirical factor. This paper tries to include the real seabed effects in a near-field explosion underwater explosion events by using the Coupled Eulerian-Lagrangian (CEL) method. The effect of water, soil and the TNT are approached by using the Eulerian formulation with specified Equation of status (EOS). The Us-Up’s form of Mie-Gruneisen equation is used for the water and soil. The soil’s strength is described by linear Drucker-Prager yielding function. The Jones-Wilkins-Lee (JWL) equation of state is used for TNT. The steel is approached by shell elements in a Lagrangian scheme. The strain rate effects have been considered through the Cowper and Symonds equation. The coupling between Eulerian and Lagrangian formulation is done by the general contact features provided by Abaqus Explicit solver. The simulation results are discussed in details with respect to the water, soil and pipeline deformations respectively. Additionally, the axial force is also discussed. It is shown that the seabed plays an important role during the explosion and the empirical factor used to exaggerate the TNT mass is over-conservative. In the near-field explosion, the existence of soil may be beneficial to the pipeline’s damage. Global effects may be also triggered due to the large axial force generated during the explosion.
Safety Evaluation Technique of Annular Pressure in Offshore High-Temperature High-Pressure Gas Wells
Authors: Li Yanjun , Liu Shujie , Gao Deli , Zhang Zhi , Long Yang 
Published: October 2022

Abstract
The high-temperature high-pressure (HTHP) nature gas reserves in the South China Sea are 15 trillion cubic meters, accounting for approximately one-third of the total oil and gas resources in the South China Sea. There are many leak risk points of the HTHP wellbore, so it is very difficult to guarantee the wellbore integrity, and the annular pressure seriously threatens the test and construction security. Based on the safety assessment technology study of the annular pressure offshore HTHP gas fields, this paper designed the whole-life-cycle annular pressure management model and operation measures, developed the risk assessment technology of wellbore integrity, compiled the annular pressure diagnosis model, developed the calculation software of annular pressure critical control value, etc. And then, the critical control value of wellbore pressure can be calculated much more quickly and accurately for different production time, which could better manage the wellbore pressure risk and ensure the wellbore integrity. The safety assessment technology study result in the paper has been applied successfully in Yingqiong (YQ) Basin and achieved “zero” annular pressure during the on-site drilling, completion, and production operations.
Assessment of Situation Awareness for Seafarers Using Eye-Tracking Data
Authors: Virdi S. S. , Ng Yong Thiang , Liu Yisi , Tan Kelvin , Zhang Daniel 
Published: October 2022

Abstract
Situation Awareness (SA) is the perception of the current situation, comprehension of its meaning, and projection of what is going to happen in the near future. It is crucial for navigators to possess high SA in a navigational Bridge to mitigate the risk of human errors and to improve navigational safety. However, the current methodology to assess SA mainly rely on human experts, which might bring in potential problems such as bias, work overload, and it is also hard for the human experts to capture every fine detail of the behaviour of the seafarers being assessed. To overcome these, an objective and automated way to assess Situation Awareness is needed. In this work, eye-tracking data is used for the assessment of SA. With the eye tracking device, it is possible to localize where the navigator is looking at, and by applying computer vision with deep learning algorithm, the ongoing activity being executed by the navigator could be identified. In total 7 activities (using RADAR, ECDIS, checking of ship’s heading, and speed, checking data on Echo Sounder, and data related to ships maneuvering, and others) can be recognized which are used as indicators of SA. A set of training data was recorded using Tobii Pro Glasses 3 to train the deep learning algorithm and test the classification accuracy. To further verify the proposed eye-tracking based assessment, a preliminary experiment has been designed and carried out. Five subjects were recruited for data collection. A full-mission Advanced Navigation Research Simulator (ANRS) was used to provide scenarios for both training data collection and preliminary experiment. From the initial results, it shows that a recognition accuracy of &gt; 99% can be achieved, which gives positive support to the eye-tracking based recognition. The analytics results using data from preliminary experiment also show great potential in using eye-tracking to assess SA of navigators. The proposed assessment could be used in both simulator and on-board and for multiple purposes such as performance evaluation, promotion to the next rank, and Continuing Professional Development.
Influence of Gap Width and Artificial Damping on Gap Resonance
Authors: Ekerhovd Ivan , Ong Muk Chen , Zhao Wenhua 
Published: October 2022

Abstract
Side-by-side offloading between two vessels in offshore operations, creates a narrow gap where blistering free surface motions may be excited due to resonant responses. The present study investigates what influence gap width and artificial damping has on these motions. We run a series of numerical simulations, based on a 3D linear potential flow solver using a numerically validated model from our previous work. The model is meant to simulate a floating liquefied natural gas (FLNG) facility, an LNG carrier, and the narrow gap created between them. In this study, the resonant fluid motions in the gap are investigated based on a configuration where both vessels are fixed. The results show a significant impact on the response of the gap resonance with diverse gap widths. By applying artificial damping to the free surface, we found that there is no significant effect on the resonant motions of the gap surface after the gap width reaches a significant fraction of one ship breadth.
Scenario-Based Risk Management for Arctic Waters
Authors: Bergström Martin , Browne Thomas , Ehlers Sören , Helle Inari , Herrnring Hauke , Khan Faisal , Kubiczek Jan , Kujala Pentti , Kõrgesaar Mihkel , Leira Bernt Johan , Parviainen Tuuli , Polojärvi Arttu , Suominen Mikko , Taylor Rocky , Tuhkuri Jukka , Vanhatalo Jarno , Veitch Brian 
Published: October 2022

Abstract
Arctic shipping is growing driven by a demand for natural resources, climate change, and technological development, among other factors. While this provides many benefits for society, it also entails risks for people, the environment, and property. The purpose of this article is to assist ship designers, operators, owners, and other stakeholders in managing those risks by defining a comprehensive approach to scenario-based risk management for Arctic waters. The approach covers both the management of short-term operational risks, as well as of risks related to a ship’s long-term extreme (design) ice loads and structural response. For operational risk management, a further developed version of the established Polar Operational Limitations Assessment Risk Indexing System (POLARIS) method is defined. In contrast to the established method, the further developed version considers the consequences of potential accidental events. For managing risks related to a ship’s long-term extreme ice loads and structural response, guidelines are provided for the application of existing methods of assessing ice loads, including analytical, numerical, and semi-empirical methods. In addition, to support the design of ice class ship structures, a new approach based on closed-form expressions is defined that can be used in the conceptual design phase to determine preliminary scantlings of primary hull structural members (e.g., transverse web frames).
Calculation of Thrust and Torque of a Tandem Propeller Using a Combined Vortex Lattice Lifting Line Method
Authors: Büsken Andreas , Krüger Stefan 
Published: October 2022

Abstract
This paper describes two procedures for the calculation of thrust and torque coefficients of a tandem propeller. Both procedures are based on a Combined Method, which consists of a Vortex Lattice calculation combined with an extended Goldstein approach. The first procedure performs individual calculations for the two propellers. To account for the interaction of the two propellers the consecutive calculations are linked. Since the linked procedure includes some simplifications it can be used only for calculations in homogeneous inflow. To perform calculations in inhomogeneous inflow or account for additional effects the second procedure is implemented, which carries out the combined calculation for the whole tandem propeller. This allows the direct calculation of the propellers’ influence on each other. The results of the two procedures are compared to measured data from open water tests.
Investigating Hull Blockage and Thruster-Hull Effects on an ASD Tug
Authors: Yiew Lucas J. , Taskar Bhushan , Zheng Yingying , Magee Allan R. 
Published: October 2022

Abstract
Interactions between a vessel’s hull and its propulsor are important design and engineering considerations. For vessels equipped with azimuthing propulsors, these interactions are compounded due to the ability of propulsors to direct thrust over a wider arc, even into its own hull. In this study, we examine the interactions between a pair of thrusters and the hull of an azimuthing stern drive (ASD) tug. Specifically, we analyse thruster-on-hull effects, which can materialise as increases in hull drag when flow around the hull is altered by a thruster, or when thrust is vectored towards the hull and impeded by hull surfaces. A series of captive model tests were conducted to evaluate these effects using static and dynamic planar motion mechanism (PMM) tests, in both bare hull and appended hull configurations. Results from this study identify the conditions contributing to thruster-on-hull interactions, and provide further insights into physical mechanisms affecting thruster and hull performances in different flow regimes.
Numerical Evaluation of the Thermal Performance of Modern Offshore Wind Farm Cables Installed in J-Tubes
Authors: Delizisis Panagiotis , Kokkinos Charilaos , Chatzipetros Dimitrios , Pettas Dionisis , Chrysochos Andreas I. , Loukas Konstantinos 
Published: October 2022

Abstract
The submarine cables used to interconnect Offshore Wind-Farms (OWFs) with the mainland typically pass through large, metallic risers having a J-shape when approaching the Wind Turbine Generators (WTGs). These so-called “J-Tubes” consist of three main parts: water, air and platform sections. The air-section is typically sealed at both ends for practical reasons: its bottom is bounded by the water surface, while the top end by means of the armor hang-off cap. Hence, the cable may experience adverse thermal conditions within this enclosed section and the latter is likely to be the thermal bottleneck of the entire subsea route. Unfortunately, no Standardized method currently exists to calculate the current rating of cables installed in J-Tubes. This paper evaluates the applicability of the semi-empirical formulae existing in literature given the modern export cable and J-Tube designs presently used, which in many cases can give Ra numbers substantially higher than 2.3 · 106. Computational Fluid Dynamics (CFD) coupled with heat transfer analysis is employed for this purpose, while simpler heat transfer models applying the existing analytical methods are also used for comparison purposes. Furthermore, the cable is represented in a more realistic way and the convective heat transfer in the filler interior is also considered. As demonstrated in the paper, the use of analytical methods gives relatively good results for lower Ra numbers compared to the more realistic numerical models developed. However, the analytical methods may lead to very optimistic conductor temperature values when Ra becomes higher than 2.3 · 106, thus making their use rather questionable for larger J-tubes.
Proposal for Cyclic Riser Load Methodology Using High-Resolution Current Data
Authors: Moldestad Lasse , Reinås Lorents , Sætre Stian , Johnsen Øistein 
Published: October 2022

Abstract
Both in riser design and life extension exercises, analytical models are used to determine loads and load effects. For cyclic load assessments it is known that applied current load is an important modelling factor. In guidelines and codes for riser systems, such as DNV-RP-E104 and DNV-RP-F204, the prescribed methodology for including current in the analytical models is usually limited to scenarios with limited available statistical current data. This typically has the effect that the intended approach becomes to implement current conservatively in the analytical models, commonly applying a low current velocity. This paper presents results and findings from case studies of top tension marine drilling risers in shallow water, analyzed using 2D wave energy spectra with alternative approaches for current: high-resolution current velocity and direction data approach, and typical current loading approaches based on DNV-RP-E104. The different approaches are further investigated and supplemented by parameter sensitivity assessments. Based on the above, a methodology is proposed on how to implement current loading for cyclic load analysis when high-resolution current data is available, and the potential benefit of the improved prediction is shown. The motivation behind the proposed methodology is to provide an improved cyclic load prediction method for scenarios where high-resolution current data is available. This may be of particular interest for life extension exercises where historic cyclic riser loads can be reassessed based on historical environment and operational data.
State of the Art in New Semisubmersible Platform Concepts
Authors: Wang Tianying , Cui Qing 
Published: October 2022

Abstract
The semisubmersible platform (Semi) shows superior performance to the Spar, TLP and FPSO owing to its unique and reasonable structure and shape, and thus is one of the most vital and promising equipment for deepsea oil and gas development. Nevertheless, its inherent disadvantages have been gradually revealed through six decades of extensive engineering practices and in-depth research. Much innovative work has been carried out during recent two decades to improve its overall performance and maximize its safety and operability to utilize it in supervisor ways. Firstly, the shape features of a conventional Semi and the operation requirements in different phases during the whole life cycle of a Semi were summarized. Then, the factors affecting the stability and the motion performance of a Semi and their internal relationship were studied according to the principles of hydrostatics and hydrodynamics. After that, representative innovative conceptual Semi designs in the academic papers and the patent documents were reviewed. Finally, the directions for further innovation and growth of the Semi were predicted. This paper aims to provide some inspiration and reference to the experts and scholars engaged in deepwater offshore field development and innovative research on the floating structures.
Aspects of Collision Response of Long-Span Floating Bridges
Authors: Storheim Martin , Dørum Cato 
Published: October 2022

Abstract
Ship collisions are a notable hazard for any bridge spanning a water way. Globally, one sees an increase in the number of planned floating bridges. These long-span floating bridges have unique aspects when exposed to ship collision events due to their size, flexibility, mooring configuration and hydrodynamic effects. A large analysis scope was performed during the Ferry-free E39-project for the Bjørnafjorden crossing in Norway, of which key findings are discussed in this paper. Aspects of analysis methodology and the connection between lateral flexibility and hydrodynamic damping are discussed, as well as residual strength considerations for the bridge in damaged condition.
A Risk-Based Approach to Determine Mobile Offshore Drilling Unit Disconnect Criteria
Authors: Garlid Stian , Hørte Torfinn , Reinås Lorents 
Published: October 2022

Abstract
This paper investigated the feasibility of using structural reliability analysis (SRA) methodology to determine a mobile offshore drilling unit risk-based disconnect criteria. A notational harsh environment shallow water mobile offshore drilling unit (MODU) drilling operation case study has modelled weather conditions that result in significant nonlinear dynamic response. From this case study we have found the use of SRA methodology for establishing risk-based operation specific operating criteria feasible. We advocate operational criteria with a quantified probability of exceedance to be useful to decision makers seeking risk-based operations criteria. For this reason, this paper proposes a generic approach for using SRA intended for a range of marine operations specific operating criteria, e.g., MODU connected to a subsea well or vessel to vessel transfer.
Oil and Gas Technologies as Key Elements for a Viable Deep Sea Mining Industry
Authors: Tjåland Egil , Ellefmo Steinar Løve , Aasly Kurt , Gjersvik Tor Berge , Fichler Christine 
Published: October 2022

Abstract
Deep-marine mineral deposits, including polymetallic nodules, seafloor massive sulfides, and cobalt rich manganese crusts, are known down to 6000 meters water depths. Challenges of such extreme water depths, long distances from supply bases and the need for cost-effective technical solutions, share many similarities with challenges in the oil and gas industry. As in the case of oil and gas, the resource estimation of mineral resources depends to a large extent on geophysical measurements, including seismic and electro-magnetic measurements. Production of deep-marine mineral deposits can draw on experiences from oil and gas production from ultradeep water depths, and transportation of ore from the sea bottom can use riser technology employed in oil and gas projects. Floating Production Storage and Offloading vessels used by the oil and gas industry can be utilized to store ore from seabed mining before transport to onshore mineral processing facilities or, less likely, for mineral processing on the seabed, or onboard the Floating Production Storage and Offloading vessel. However, the large sea depths and the high investments needed to achieve a minimal ecological footprint, will need many innovations and new solutions. Such challenges are similar to what the oil and gas industry has developed for oil and gas exploration and production in deep water. Here we show how technologies from the oil and gas industry can be applied for deep sea mineral extraction.
Fatigue Assessment of Pump Tower in LNG Membrane Tanks
Authors: Storhaug Gaute , Sun Hui , Zang Yuelong , Rognebakke Olav 
Published: October 2022

Abstract
Membrane tanks are used for marine transport and storage of LNG, while LNG fuel tanks is an emerging application. LNG carriers operate with almost full or almost empty membrane tanks, while storage tanks on FSRUs and fuel tanks experience all filling levels. Partly filling may give rise to increased sloshing responses on the pump tower structure inside.
DNV has published rules for alternative survey arrangement for FSRU/FSUs, which opens for longer tank inspection intervals. This alternative survey arrangement can be applied provided that the damage risk is less or equivalent to regular tank inspections intervals as an LNG carrier. The challenge is how to assess this equivalence. A definition of the reference vessel and trade is required.
This paper addresses a new proposed methodology to quantify the relative pump tower fatigue. It is built up of several steps that will be explained including hydrodynamics, satellite tracking, CFD, load combination, fatigue analysis and visualization. This is first done for a representative LNG ship and trade. The methodology is then applied for an FSRU. Combinations of filling levels relevant for the FSRU and artificial wave environments are studied to quantify when the resulting fatigue may exceed the LNG carrier reference case. Uncertainties and challenges are discussed.