bluuebunny/crossref_metadata_2025_split huggingface dataset:
Connectivity and climate change drive the global distribution of highly invasive termites
Authors: Duquesne Edouard , Fournier Denis 
Published: April 2024

Termites are amongst the most abundant and ecologically-important groups of insects in tropical forests. However, the destructive potential of some species amounts to billions of dollars in damage each year. Despite their economic and ecological impacts, only a limited number of invasive termite species have been studied using distribution modelling and no studies have taken trade, transport and demography variables into account. We used Species Distribution Models (SDMs) to investigate the potential distribution of 10 highly-invasive termites. Our study includes bioclimatic conditions, land-use patterns, elevation and connectivity predictors (i.e. urban areas, human population, accessibility to cities and private vessels), alongside different climatic and socioeconomic change scenarios.
The distribution of the termite species hinges on bioclimatic and connectivity variables, highlighting the significance of these latter factors in invasive species analyses. Our models demonstrate the potential of these invasive termites to thrive in large urbanised and connected areas within tropical and subtropical regions and to a lesser extent within temperate regions. As climate changes and urbanisation intensifies, most species’ range could expand, particularly under a “fossil fuel-driven development” scenario. Furthermore, while some species may have a slightly reduced range, they could extend their presence into more urbanised and connected areas, increasing the risks and costs associated with termite damages. Our models highlight the anticipated role of growing connectivity and climate change dynamics in facilitating the widespread proliferation of invasive termites in the coming years.
Vers un enseignement secondaire moderne et démocratique ?
Authors: Fabre Mélanie 
Published: April 2024

Cet article propose une introduction à la déposition de Jean Jaurès réalisée le 25 février 1899 devant la commission d’enquête parlementaire chargée de la réforme de l’enseignement secondaire sous la direction d’Alexandre Ribot. Ce travail revient sur le contexte de l’enquête – concurrence des établissements secondaires libres défavorable aux collèges et lycées publics – et analyse la manière dont Jaurès se positionne sur les différents points traités par la commission, comme la question du maintien de l’examen du baccalauréat, celle de la revalorisation de la filière moderne, sans grec ni latin, ou encore celle de l’ouverture de l’enseignement secondaire et aux classes moyennes et populaires, scolarisées dans l’ordre primaire. Jaurès navigue alors entre attachement à la tradition universitaire classique, dont il est le produit, et conscience de la nécessité de faire évoluer l’enseignement secondaire pour lui permettre d’être en phase avec la modernité et de se démocratiser.
La politique étrangère de Joe Biden : priorité chinoise et leadership rétréci
Authors: Kandel Maya 
Published: April 2024

Joe Biden avait promis de restaurer le leadership américain après Donald Trump et de concentrer les ressources et l’attention de la politique étrangère des États-Unis sur leur principal rival et défi stratégique : la Chine. Son administration a réussi à renforcer les bases industrielles de la compétition technologique avec la Chine. Mais l’impasse des affrontements en Ukraine et le conflit à Gaza ont aussi illustré les limites de ce leadership, rétréci à l’Occident et de plus en plus contesté ailleurs par la Russie, la Chine et les pays dits « du Sud global ». Le bilan général ressemble ainsi, comme sous Barack Obama, à un pivot contrarié .
Independent Game Production in Southern China
Authors: Davies Hugh 
Published: April 2024

This article examines the interplay between commerce and creativity within Southern China’s game development by examining three sites of tension within that media production sector. These are the long hours demanded by the digital media industries in which many independent game makers are employed; the tight government controls dictating what game content can be published; and the commercially driven game types that many independent game makers rally against. Revealed here is that strict videogame regulation policies enacted by the Chinese government are experienced as a positive force by many independent game makers. These government policies prevent commercial games from dominating the market, thereby enabling a space for independent games and their makers to exist. These commerce/creativity dialectics in Southern China connect to media industries globally and highlight the resilience of Chinese indies in balancing commercial, creative, and governmental constraints. Drawing on recent scholarship combined with ethnographic fieldwork, this article expands awareness of game production beyond Anglo-centric and neoliberal understandings by illuminating understanding of Southern China’s independent game community and the circumstances of their creative practice.
La place des outre-mer du Pacifique dans la stratégie française et l’architecture régionale de sécurité
Authors: Gravelat Caroline 
Published: April 2024

La contribution de la France à la sécurité et à la stabilité de la région Pacifique répond prioritairement à des besoins nationaux et à une responsabilité de voisinage. L’action de la France dans le Pacifique s’inscrit dans une architecture complexe qui mêle acteurs infranationaux (les territoires français), nationaux (gouvernement de la République) et supranationaux (Union européenne) autonomes les uns par rapport aux autres. Ce maillage, par lequel chaque acteur participe, chacun dans son domaine de compétences, à l’architecture régionale de sécurité implique adaptation, coordination et nuance dans l’appropriation de l’action. Deux des trois collectivités françaises du Pacifique, jouissent en effet d’un tel niveau d’autonomie, qu’elles peuvent devenir membre d’organisations internationales, après accord de l’État, nommer des représentants auprès des États de la région et signer des engagements politiques, la seule limite étant la signature d’engagements internationaux juridiquement contraignants pour laquelle, elles doivent obtenir les pouvoirs de la République. Elles peuvent donc conduire leur propre diplomatie en quasi-liberté. Ces contraintes de « partage de souveraineté » amènent à s’interroger sur la place réelle des collectivités françaises du Pacifique à la fois dans les stratégies nationale et européenne ainsi que dans l’architecture régionale.
Untethered Pressure Sensor Conveyance for Bottomhole Pressure Measurement
Authors: Seren H. , Hillman T. , Zeghlache M. Larbi , Deffenbaugh M. , Naseer F. , Thiel Tim 
Published: April 2024

Abstract
Bottomhole pressures of wells are commonly used to evaluate reservoir characteristics such as permittivity and permeability and connectivity between wells. To measure bottomhole pressure, a sensor needs to be conveyed either through an invasive method such as wireline, or it can be permanently installed downhole. These methods can be costly. In this paper, we are introducing a new conveyance method using an untethered well logging tool. We used an untethered well logging tool that can autonomously move in the vertical parts of liquid wells by changing its buoyancy. It takes a small dissolvable weight to descend in a well, and at a programmed depth the weight is released to make the tool buoyant. The recorded data can be retrieved after the tool returns to the surface. We expanded this tool’s capability so that it can land at the bottom of the well and stay for a programmed time frame. To do this, the dissolvable weight was coated to delay the dissolving time during the logging which also eliminated exothermic heating due to the dissolution process. For the demonstration a 900-ft deep test well with 4-in casing was used that has no connectivity with the formation. The tool was programmed to release its weight 6 hours after the start of the logging. Since the tool moves around 0.35 ft/s speed, this provided more than 5 hours of time frame for continuous recording of the pressure and temperature at the well bottom. The tool was collected from the well 6.5 hours after the deployment and the data was downloaded. As expected, the pressure stayed constant during the test. A very low-cost conveyance method was demonstrated for pressure sensor placement at the well bottom.
Qualification of a Subsea Pump for Dense Phase Fluid Applications in Brazilian Deep-Water Pre-Salt Fields
Authors: Kus B. , Schneider L. , Bourne M. , Cunha L. S. , Machado H. , Bidart A. M. F. , Passarelli F. M. , Vieira A. J. M. , Spelta M. J. M. , Moura D. A. G. , Oliveira F. S. , Silva N. E. , Brandão A. A. T. E , Da Silva Campos R. , Da Silva L. C. T. 
Published: April 2024

Abstract
An extensive de-risking program was conducted to qualify the subsea dense gas pump project design. As part of this program, a subsea pump prototype, a back-to-back centrifugal pump, was designed, constructed, and evaluated using a dense CO2/N2 mixture, referred to as dense gas. This dense fluid has a gas-like viscosity, but a density closer to that of a liquid.
The pump prototype was evaluated at varying suction pressures ranging from 150 to 200 bar, up to a maximum discharge pressure of 350 bar. The machine was operated at a maximum speed of 6,000 rpm, delivering a flow rate of up to 700 m3/h of gas mixture. The composition and pressure of the working fluid was selected to simulate Brazilian Pre-salt field conditions at the seabed. A vertical integrated pump-motor unit with environmentally friendly barrier fluid (BF) was configured using radial centrifugal impellers in a similar fashion as a multiphase subsea booster, to pump the homogeneous dense mixture.
The main objectives of the test campaign were to validate the hydraulic performance prediction and assess the rotordynamic behavior of the pump when operated with a dense fluid. Additionally, a series of slug tests were performed to prove the robustness of the pump in case of the transient high-load scenarios. The pump passed all the required tests and demonstrated anticipated robustness, which is crucial for subsea operation. The measured hydraulic performance exceeded predictions at high-load, high-speed conditions, which may be partly attributed to the conservatism in the selection process.
The successful combination of hydraulic performance, robust rotordynamic behavior, and an efficient control strategy provides strong evidence for the viability and effectiveness of the current subsea pump design for dense gas application.
Comparison Between Coupled and Uncoupled Dynamic Analysis of Floating Offshore WTG Support Structure
Authors: Gupta A. , Desai A. , Sarada S. , Seo B. 
Published: April 2024

Abstract
This study presents a comparative analysis of hydrodynamics for floating offshore structures, with a focus on the coupled and uncoupled analysis methods for a floating offshore Wind Turbine Generator (WTG) support structures. The primary objective is to assess the impact of these two parallel methods on key parameters such as fairlead tension and platform responses. The hydrodynamic analysis performed for this study employs two distinct software platforms, OpenFAST by NREL (National Renewable Energy Laboratory) and MOSES by Bentley, and highlights the effects of using coupled and uncoupled methods for response characteristics of the mooring lines. The authors conducted a similar study on the fixed offshore WTG support structure. This study established a benchmark methodology for the industry to calibrate uncoupled analysis to facilitate the exchange of information between turbine manufacturers and substructure designers within the restrictions of intellectual property rights. The study proposes checks and balances to verify intermediate outputs at various stages of design development. (Gupta, et al. 2023).In this study, VolturnUS-S reference floating offshore wind turbine semisubmersible designed by University of Maine along with International Energy Agency (IEA)-15- 240-RWT 15 megawatt (MW) reference wind turbine is used for the analysis. For the coupled analysis, an integrated global model of the floating hull structure with a WTG is modeled in OpenFAST and the coupled effect is captured by combining the hydrodynamic and aerodynamic responses. For the uncoupled analysis, response is generated by combining the hydrodynamic forces calculated in MOSES with aerodynamic forces using the AeroDyn module from OpenFAST. Results from both analyses are compared and presented in the paper.The coupled analysis provides a comprehensive representation of the system's behavior, capturing intricacies of the coupled behavior of the integrated model. In contrast, the uncoupled analysis simplifies the system but may potentially overlook vital coupling effects. The study contributes to a deeper understanding of the coupled and uncoupled analysis methods and their implications while providing valuable insights to engineers for the design process with respect to the varying effects of these methods on dynamic behavior of the integrated system.
Feasibility of Steel and HDPE Sea Water Intake Risers for Deepwater Applications
Authors: Mercan B. , Volk B. L. , Campbell M. , Guerin P. 
Published: April 2024

Abstract
There is a growing desire in the offshore oil and gas industry to lower CO2 emissions from operations, especially in FPSOs and FLNG units. One method to lower CO2 emission is to reduce power consumption by improving the cooling system so that it utilizes colder water from deep sea. Traditionally, Sea Water Intake Risers (SWIRs), which are usually made of reinforced rubber hoses, are used to supply water from water depths up to 150m to the topside, resulting in an in-take temperature of at least 15°C. Nowadays, many operators have been trying to reach colder water (5-7°C) with target SWIR depths up to 700 m in order to support emission reduction efforts. However, there are many design and material restrictions to achieve this goal. Therefore, this paper focuses on the feasibility for steel and HDPE SWIR configurations for deep sea applications (up to 700m).
Conducting a site-specific feasibility assessment at early design stage plays an important role in selecting an optimum SWIR configuration. The main pipe of the SWIRs is generally made of reinforced rubber, steel, or high-density polyethylene (HDPE). The SWIRs are installed in a free hanging configuration at the keel or on the sides of the FPSO. Their design can be challenging for deep water applications due to harsh environmental effects (i.e., wave and current). Interference with adjacent structures such as production risers or mooring lines can make their design even more complicated.
In order to investigate the feasibility of 350 m and 700 m SWIRs, nonlinear finite element simulations are performed using HDPE and steel pipes for a conceptual field. The steel SWIRs may provide more confidence in long term reliability as steel is a conventional material for dynamic pipelines (e.g., production risers), but can lead to weight and fabrication constraints for deep water applications. HDPE is neutrally buoyant and eliminates weight restrictions but is also prone to creep, large displacements, and connection challenges.
Today, there are many SWIRs in service, operating up to 150 m water depth and their design and operational requirements are well known by the oil and gas industry. Pumping sea water at depths greater than 150 m is a significant advancement for the industry as deeper SWIRs provide colder water and further reduction in the CO2 emission of FPSO's cooling systems. This paper focuses on the challenges and design limits for deep SWIRs (350 m and 700m) made of steel or HDPE.
Exploring the Potential of Laser Technology in Oil Well Drilling: Recent Advances and Future Recommendations
Authors: Gowida Ahmed , Elkatatny Salaheldin 
Published: April 2024

Abstract
Conventional rotary drilling techniques employed in crude oil and natural gas extraction present notable challenges and financial burdens. To mitigate these obstacles and minimize drilling expenditures, oil enterprises are investigating innovative cost-saving approaches. Laser technology has emerged as a non-invasive alternative to traditional methods, garnering attention within the oil and gas sector. This study assesses the feasibility of laser drilling as a promising departure from rotary drilling practices. The research undertakes a comprehensive examination of global studies on the utilization of lasers in oil and gas well drilling, providing insights into the technology's potential and offering recommendations for its practical integration in the oilfield. Extensive lab-scale experiments have showcased the proficiency of contemporary laser models in spalling, melting, and vaporizing various rock formations, ranging from Berea sandstone to highly resilient granite and basalt. Analyzing the rate of penetration against the required specific energy under diverse conditions facilitates an assessment of the technique's efficacy. Experimental findings indicate that fluid saturation within drilled rock does not impede the drillability rate. Advantages over conventional methods include heightened penetration rates, reduced tripping, casing, and bit costs, improved well management, and enhanced side-tracking capabilities. Consequently, laser technology promises to facilitate sustainable field operations, offering manifold benefits in operational efficiency, cost reduction, and environmental preservation. Nevertheless, technological challenges such as borehole cleaning, well control, beam downhole delivery, and complex formation conditions necessitate further exploration. The development of laser-assisted drill bits and downhole laser drilling machinery holds promise with advancing laser technology and sustained research into the technique's viability from both technical and economic standpoints. Crucial technical recommendations for laser drilling technology in the oil and gas industry encompass conducting feasibility studies, investing in research and development, validating technology through field trials, prioritizing safety and environmental concerns, performing cost analyses, instituting training programs, ensuring regulatory compliance, fostering collaboration and knowledge exchange, and continuously monitoring and enhancing performance. Adhering to these recommendations enables the industry to optimize drilling efficiency, curtail costs, and champion environmental stewardship, thereby advancing sustainable practices in oil and gas exploration.
Application and Experience of Hydrogen Deoxidizers in Seawater Deoxygenation Systems
Authors: Isdahl O. M. , Shamshiri S. 
Published: April 2024

Abstract
The scope of the research presented in this paper encompasses over 25 years of cumulative experience in employing hydrogen deoxidizers within water deoxygenation process systems. Seawater is injected into the system to strip the O2 from water by means of inert nitrogen gas. In these systems, the nitrogen stripping gas is circulated in a closed loop and regenerated over a chemical catalytic reactor, where a purity of at least 99.995 % is achieved. This paper presents empirical data derived from the operation of these systems.
A test system has been purpose-built to leverage several years of experience gained from hydrogen-fueled water deoxygenation in analogous onshore systems, with the aim of making it applicable to a new seawater deoxygenation system. This system is designed to purify a nitrogen stream, which is utilized to remove oxygen from seawater. Consequently, the nitrogen stream initially contains oxygen, and it is reused for the deoxygenation process, necessitating the removal of oxygen. The elimination of oxygen occurs within the hydrogen deoxidizer by introducing hydrogen upstream of a reactor equipped with a palladium catalyst. Hydrogen and oxygen react to produce water. The gas stream is driven by a liquid jet compressor, and the research presents operational procedures encompassing the control of hydrogen levels in the gas stream, control system considerations, safety protocols, and the regulation of other process variables, such as temperature, both upstream and downstream of the reactor. Notably, nitrogen shares similar thermal properties as hydrogen, and the reaction characteristics within such a reactor closely resemble the reaction in deoxo-reactors for deoxygenation hydrogen in Alkaline hydrogen production by electrolysis.
Results from hydrogen deoxidizer performance will be presented together with design considerations for generic hydrogen deoxo-reactors. Historically, this process has been driven by methanol offshore, and the paper will explore the feasibility of offshore on-demand hydrogen generation for the deoxo-reaction and evaluate alternatives for the supply of hydrogen such as storage solutions.
The novelty of the research is the combination of hydrogen deoxo-reactors with other process streams in combination with the seawater deoxygenation process.
Hybrid Structural Health Monitoring of an FPSO: Measuring Stress at Un-Instrumented Structural Details
Authors: Andoniu A. , de Lauzon J. , Pidery K. 
Published: April 2024

Abstract
Well designed and implemented Asset Integrity Management strategies are key to ensure safe operations and high availability of assets. In a world where data is king and data-driven decisions are becoming the norm, it will be difficult to imagine such strategies without the extensive use of monitoring technologies.
In the past years, Bureau Veritas has developed a hybrid Structural Health Monitoring technique that combines strain gauge measurements with state-of-the-art hydro-structure simulations. At the core of this approach lies the conversion matrix method: by projecting the structural response on a carefully chosen basis of distortion modes, a relationship can be found between any physical quantities related to hull deformation. In this manner, stresses anywhere on the structure, including un-instrumented structural details, can be expressed as a function of stresses at only a few instrumented locations.
However, accurately reconstructing structural response at locations where local effects are present can be challenging in all types of hybrid monitoring methods. This paper aims to show that these difficulties can be overcome, and the conversion matrix method can be successfully applied to reconstruct the local stress response at side shell stiffeners of an FPSO. Several sensor configurations used as input in the conversion matrix are tested and discussed. Validation is performed by comparing thousands of hours of direct sensor measurements with reconstructed stress time histories. The results show consistent improvement compared to virtual monitoring which is exclusively based on numerical simulations using encountered sea states.
Hybrid Structural Health Monitoring is the key to cost-effective monitoring. By leveraging the power and flexibility of numerical simulations, the capabilities of direct measurements are expanded to reach the entire structure, even at un-instrumented locations subjected to local effects.