bluuebunny/crossref_metadata_2025_split huggingface dataset:
Le champ extérieur de la pesanteur et les équations fondamentales de la géodésie dynamique
Authors: Bragard Lucien 
Published: April 2023

Considering one reference level surface, not external to the topographical earth surface, which contains an equal mass and turns round the same axis of rotation, the author proves the two fundamental equations of the dynamical geodesy (boundary conditions satisfied for the disturbing potential) valuable to the linear approximation for the distances between the two surfaces, respectively for the continental and ocean parts of the topographical earth surface.
Then, the integral equation is obtained, which gives the disturbing potential. Taking into account the boundary conditions, it is possible to get the local distance between the two surfaces in function of the values either global or regional of the measured gravity, the theoretical gravity and the vertical gradient of the theoretical gravity, by means of an integral equation.
For the case where the reference surface is partly external to the topographical surface, the author introduces an external level surface and gives two integral equations to solve the problem regionally.
Espaces-temps du vide admettant une congruence caractéristique simple intégrable
Authors: Cahen Michel , Leroy Jules 
Published: April 2023

We construct the empty space metrics which possess a shearing hypersurface orthogonal eigenvector. Three classes of metrics are obtained, each class depending on one arbitrary constant.
We prove that these metrics are of Petrov type I and that they possess another hypersurface orthogonal eigenvector. We also prove that the spherical metrics admit one Killing vector and two commuting conformai Killing vectors.
Écoulement magnétohydrodynamique en tube de section carrée en présence d'un champ magnétique transversal. Cas où les parois parallèles au champ magnétique sont conductrices
Authors: Jaumotte André Louis , Hirsch Charles , Troch Jean-Louis 
Published: April 2023

Nous présentons dans cette note :
— Les principaux résultats théoriques obtenus pour une section rectangulaire suffisamment large pour que l'écoulement puisse y être considéré comme unidimensionnel (écoulement entre deux plaques parallèles isolantes, un circuit extérieur reliant les deux plaques parallèles au champ magnétique, celles-ci étant rejetées à l'infini).
— Les résultats des mesures effectuées sur un tube de section carrée dont les deux parois perpendiculaires au champ appliqué sont isolantes et les deux parois parallèles au même champ sont conductrices. Ces mesures portent sur :
— la modification du gradient de pression lorsque le débit, le champ appliqué et le courant extérieur varient ;
— la différence de tension à circuit ouvert entre les plaques conductrices en fonction du débit et du champ magnétique appliqué.
Thermalisation du positron dans le plasma des électrons de conduction d'un métal
Authors: Brouers François 
Published: April 2023

On montre que le temps de thermalisation d'un positron dans le plasma électronique d'un métal, calculé en prenant le potentiel effectif de la théorie de la réponse linéaire pour décrire l'interaction électron-positron, est nettement plus grand que celui calculé dans une approximation statique par Lee-Whiting.
Pour l'aluminium, le processus de thermalisation est à peine trois fois plus rapide que le processus d'annihilation. Il semble donc bien que l'on ne puisse considérer, comme c'est généralement admis, que, dans les métaux, le positron est toujours thermalisé avant son annihilation.
СОЦІАЛЬНА СТІЙКІСТЬ СІМ’Ї ЯК ПРІОРИТЕТ ОСВІТИ ДОРОСЛИХ В УМОВАХ ВОЄННОГО СТАНУ
Authors: Пєхота Олена , Купенко Олена 
Published: April 2023

Об’єктом дослідження є соціальна стійкість сім’ї в умовах воєнного стану. Цей феномен визначається через спільні переконання, спільні організаційні процеси, спілкування та спільні процедури вирішення проблем у сім’ї у відповідь на руйнуючі події та лиха. Окрема увага приділена чинникам соціальної стійкості сімей із дітьми, їх базовому стану, навчанню та вихованню дітей в умовах воєнного стану. Метою статті є обґрунтування змісту соціальної стійкості сім’ї як пріоритету освіти дорослих. В якості методології для цього використовується педагогіка пригноблених Пауло Фрейре. Генеративні слова і генеративні теми, сказані людьми в їх життєвих реаліях, розглянуто як освітні інструменти і як освітні результати, а також чинники подальшого поглиблення змісту навчання як практико-орієнтованого партиципаторного дослідження тих, хто навчає і навчається. Представлене в статті дослідження спирається на емпіричну базу проекту «Гендерні аспекти соціальної стійкості територіальних громад», включаючи соціологічне опитування, фокус-групове інтерв’ю, стратегічну сесію. Реалії життя цільових груп освіти дорослих, з урахуванням складних життєвих обставин та їх підсилення в умовах воєнного стану, зафіксовані в ході фокус-групового інтерв’ю у вигляді генеративних слів «житло і дім», «базовий стан», «діти», «навчання», «сім’я», «робота», «фінансовий стан», «здоров’я». Один із варіантів пріоритетної для дорослих проблематики зафіксовано зі слів учасників стратегічної сесії у вигляді генеративних тем: «дитина як особистість», «ми в родині говоримо», «не пощастило із школою», «я не потягну дві школи (приймаючої країни та українську)», «без коріння». За виділеними генеративними темами запропонована репрезентація, що включає суб’єктів, механізми, приклади дії, виклики, пов’язані із цією дію, чинники вразливості та стійкості сім’ї. Запропонована репрезентація включає також ідею про те, що і дорослі, і діти потребують спеціальної системної підтримки в умовах воєнного стану. Причому, надана така підтримка має бути як із боку освіти дорослих, так і з боку стійкої сім’ї. Однак запропонована дана репрезентація як пріоритетний варіант для обговорення та подальших практико-орієнтованих партиципаторних досліджень в освіти дорослих.
Ключові слова: соціальна стійкість сім’ї; освіта дорослих; педагогіка пригноблених; генеративне слово; генеративна тема; партиципаторне дослідження.
On Enumeration and Entropy of Ribbon Tilings
Authors: Chen Yinsong , Kargin Vladislav 
Published: April 2023

The paper considers ribbon tilings of large regions and their per-tile entropy (the logarithm of the number of tilings divided by the number of tiles). For tilings of general regions by tiles of length $n$, we give an upper bound on the per-tile entropy as $n - 1$. For growing rectangular regions, we prove the existence of the asymptotic per tile entropy and show that it is bounded from below by $\log_2 (n/e)$ and from above by $\log_2(en)$. For growing generalized "Aztec Diamond" regions and for growing "stair" regions, the asymptotic per-tile entropy is calculated exactly as $1/2$ and $\log_2(n + 1) - 1$, respectively.
Peran Mediasi Keputusan Pendanaan Pada Peran Struktur Aktiva Terhadap Nilai Perusahaan Pada Perusahaan Idx-80
Authors: Husain Fauziah 
Published: April 2023

Penelitian ini bermaksud untuk menganalisa dampak struktur aktiva pada keputusan pendanaan, struktur aktiva pada nilai perusahaan, keputusan pendanaan pada nilai perusahaan serta peran mediasi keputusan pendanaan pada pengaruh struktur aktiva kepada nilai perusahaan dengan memakai prosedur riset kuantitatif. Teknik pemilihan sampel yang digunakan adalah purposive sampling dan diperoleh 73 perusahaan IDX-80 periode 2019-2021 sehingga total sampel yang digunakan dalam penelitian ini sebanyak 219 sampel. Penelitian ini menggunakan analisis jalur (path analysisi) sebagai metode analisi data. Hasil penelitian menunjukkan bahwa model yang terpilih adalah Random Effect Model (REM) yang menunjukkan struktur aktiva berpengaruh signifikan terhadap keputusan pendanaan, struktur aktiva tidak berpengaruh signifikan terhadap nilai perusahaan, keputusan pendanaan tidak berpengaruh signifikan terhadap nilai perusahaan dan keputusan pendanaan tidak mampu memediasi pengaruh struktur aktiva terhadap nilai perusahaan. Kata kunci: Struktur Aktiva, Keputusan Pendanaan, Nilai Perusahaan
DeepStar Projects Impact on Industry Standardization
Authors: Gomes Joseph Vincent , Shamshy Shakir , Ostebo Runar 
Published: April 2023

Abstract
DeepStar® is an operator-funded Research & Development joint industry consortium including members of the oil community such as oil & gas companies, vendors, regulators, and academic/research institutes working in multidisciplinary technology areas. The DeepStar Project has been in continuous operation since its inception in 1991 and has focused on issues and technologies required to successfully tackle future development and production challenges identified by its members.1
The focus of this manuscript and extension, the presentation, will be on the numerous projects that were the baseline for current industry standards. The DeepStar program is split into six technical areas of focus from subsurface and drilling to topside and autonomous operations and everything in between. The manuscript will be written focusing on those technical areas and the supporting projects in which final documents are used within the standards.
The emphasis will be on three strategic areas of interest for our DeepStar members; first Integrity Management and the integration of our guidelines into the 1) API RP 2SIM Structural Integrity Management of Fixed Offshore Structures2, 2) API RP 2RIM Integrity Management of Risers from Floating Production Systems3 and 3) API RP 2 MIM Mooring Integrity Management.4 The second topic is DeepStar work on AUV interface standards5 and the integration of our work into API RP 17H6 and into the SWIG JIP.7 The final topic highlighted within the session on Standards is DeepStar’ continuous work on Subsea Chemical Storage and Distribution Systems Subsea8 to which DeepStar has developed the business case, background requirements, field case studies, and funding commercialization development on this topic since 2010.9
This manuscript outlines DeepStar’ strategies, projects, and accomplishments through a collaborative effort amongst operators, engineering firms, manufactories, academic intuitions, and government regulators. Through this joint effort, members have been able to minimize the cost and risk of industry-wide engagement and technology development, while at the same time making the most of the organization's particular technology achievements. This aligns with DeepStar’ vision for the development of deepwater technology, which is closely tied to the development and qualification of advanced technologies and gaining acceptance within the oil & gas community. DeepStar has continuously confronted industry-wide issues and provided a forum for discussion and technology acceleration.
Geotechnical Characterization of the US Atlantic Outer Continental Shelf Fine-Grained Cohesive Sediments
Authors: Long Xiaoyan , Fraser Jack , Adhikari Sudarshan , Hargrave Deanne , Peralta Proserpine , Scherschel Craig 
Published: April 2023

AbstractAn offshore geotechnical site investigation campaign was completed for a large wind farm development project along the US Atlantic Outer Continental Shelf (OCS) offshore New Jersey, a frontier location with few published data on soil characterization. Field exploration and a comprehensive onshore geotechnical laboratory testing program have been performed to understand the site-specific soil behavior. This paper describes the geotechnical properties of the fine-grained cohesive sediments encountered at the study site interpreted based on a consistent framework leveraging the sitewide soil data. Discussions of sample quality, soil stress history, soil compressibility and permeability, peak and critical state shear strength, strength anisotropy, and shearing rate effect for the Atlantic OCS fine-grained cohesive soils are presented from oedometer consolidation, permeability, direct simple shear, ring shear, and K0-consolidated triaxial compression and extension tests along with other conventional index and property tests.Furthermore, the Stress History and Normalized Soil Engineering Properties (SHANSEP) parameters, namely S and m, for the cohesive soils, are developed based on the specific monotonic constant volume direct simple shear (CVDSS) tests. The undrained shear strength Su profiles within the specific geotechnical cohesive soil unit developed from the SHANSEP and SP-SPW methods (Quiros, 2000) is compared to the site-specific PCPT data and laboratory undrained shear strength measurements. Comparisons of the discussed engineering properties of the Atlantic OCS fine-grained soils with other published databases for soils of the Gulf of Mexico (GOM), Offshore Trinidad, and Offshore Mozambique also are included.This paper is in a collaborative series that demonstrates the value of an integrated geoscience approach considering regulatory requirements and project design essentials. It provides a comprehensive overview of the engineering characteristics of the Atlantic OCS fine-grained soils and can assist engineers with the assignation of rate-dependant undrained shear strength parameters developed specifically for wind farm foundation design with applicability in a regional setting.
Offshore Integrity Management and Life Extension - A Vision of the Application of Subsea Robotics in Assuring Asset Integrity
Authors: Gower Andrew Stephen 
Published: April 2023

Abstract
The longer operating life of Oil and Gas fields presents challenges to the Risk Based Inspection methodology generally applied to subsea infrastructures once the operating life of projects approaches the original expected operating period or Design Life. For Life Extension, it is anticipated novel sensors or techniques will be required to mitigate the risk of infrastructure failure. There is a strong likelihood that additional requirements will be identified to conduct either an increased frequency of inspection of subsea infrastructure, or to benefit from the emergence of enhanced sensor technologies. Application of emerging sensor technologies (magnetometry, vibration analysis etc) increase the likelihood to detect equipment anomalies earlier.
Traditional inspection by video imaging with the application of additional sensors (e.g. contact CP, wall thickness) typically requires the use of a support vessel. Hence, the requirement of additional or prolonged inspection campaigns, would result in the unsustainable consequence of increasing exposure to risk, higher CO2 emissions and additional cost, while presenting a risk of increasing inspection backlog (more with the same).
There is a rapid emergence of technical solutions of vehicles as a sensor platform with enhanced robotics and autonomy. These solutions offer the opportunity to increase the frequency of inspection campaigns while reducing exposure to risk, CO2 emissions and offers opportunities to reduce inspection costs.
To be presented is the vision of the application of Subsea Robotics from a multi-energy operating Company perspective in assuring Asset Integrity in a Life Extension context. The Concept of Operations will be explored for Autonomous Underwater Vehicles, Remote Operated Vehicles, and duets with Uncrewed Surface Vessels. The challenges of operating in deepwater fields will be discussed also highlighting preliminary opportunities to provide transverse solutions applicable to the inspection requirements of the Offshore Renewable Industries.
Finally, the challenges of testing, qualification and acceptance of those emerging robotic technologies will be discussed to provide a conclusion.
Real Time Pore Pressure Calculation from Drilling Dynamics Data via Machine Learning Techniques
Authors: Reilly Matthew James , Thurmond John B , Chovanetz Koda F , Party J Mike , De Jesus Orlando , Unladi Muhlis 
Published: April 2023

Abstract
A method is proposed to calculate pore pressure at the bit while drilling using all data typically available in a modern drilling operation. This method utilizes a machine learning approach that can estimate pore pressures at the same or lesser range of uncertainty as traditional methods and can do so at the bit in real-time. Traditional pore pressure estimation while drilling utilizes a combination of data sources most of which are detected from logging while drilling (LWD) sensors placed 100's of feet behind the drill bit (where resistivity, sonic, density etc. tools are commonly placed). Furthermore, smoothing algorithms are often used to average the detection data thus increasing the offset from the drill bit to the estimated pore pressure calculation. The result of this is that the pore pressure calculation while drilling is only relevant to the formation that has already been penetrated and not being actively drilled. In hole sections where minor pore pressure changes can have significant impact on operational decisions this has obvious disadvantages. However, while drilling a well multiple sources of data from the drill bit itself are typically left unused in pore pressure calculation. Whereas traditional methods give an estimate of pore pressure after the well has already experienced a change in pressure, this method can calculate pore pressure at the bit, as the change is experienced. Another benefit of applying a machine learning model to pore pressure calculation while drilling is that the computational time is almost instantaneous.
Subsea Processing Systems: An Overview of Promising Technologies on the Subsea Factory Decarbonization Path
Authors: Basilio Leandro Pereira , Machado Priscilla Badega , Sousa Luara Katarine Silva , de Sousa Débora Calaza , de Castro Rafael Vinicius , dos Anjos Rodrigo Petrone , Andreotti Marcelo , Juliano Diego Russo , Chaney Carmela , Matos Sarah , Ryu Sam 
Published: April 2023

Abstract
The proper development of an offshore oil and gas field relies on a project's ability to deliver the maximum economic benefits while maintaining safety and environmental targets. In this sense, offshore oil and gas companies have continually evaluated ways to optimize system designs and streamline operations to ensure the achievement of these objectives. A set of technological alternatives that have been highlighted is subsea processing, which requires moving a processing system from the topsides to the seabed.
The assessment of subsea processing systems has become an important step during the field development strategy definition, especially in terms of flow assurance by mitigating hydrate and wax formation. When combined with mature subsea production technologies, the potential benefits of deploying subsea processing include enhanced reservoir recovery improved facilities availability, reduced topsides processing requirements, and reduced overall field development cost resulting in improvement of project economics. In addition, depending on the subsea architecture chosen, subsea processing can contribute to reducing the carbon footprint, which is in line with the industry's decarbonization goals.
Due to the potential benefits of the subsea processing architectures, new technologies are emerging to overcome the technical challenges to enable this transfer of strategic processes from the topsides to the subsea. The objective of this paper is to present and discuss the mapped subsea processing system archetypes that may significantly increase hydrocarbon production in a cost-optimized way for new fields, tiebacks, and operating facilities.
The mapped archetypes are implemented in an Expert System that integrates all technical areas for offshore field development, providing hundreds of conceptual alternatives to understand the impact of using subsea processing systems. This paper provides an overview of promising technologies that have the potential to increase the scope of subsea processing, leading to the identification of the most favorable architectures for each project.
This study incorporates a detailed analysis of 27 different subsea archetypes, combining processes such as liquid boosting to host, gas compression to host, two-phase and three-phase separation, produced water reinjection or disposal, seawater injection with sulphate removal, dense phase (natural gas or CO2) boosting to reinjection, gas dehydration, and gas compression. Such analysis indicated that equipment with different technological maturity levels can be combined to create a subsea processing arrangement that meets the project requirements.
Scenarios for Subsea Fields Decarbonization: A Mapping of Potential Power Schemes and Solutions
Authors: Delaplace Thomas 
Published: April 2023

Abstract
The objective of this paper is to map the potential levers available to meet the ambitious commitments taken by the Oil & Gas industry to reduce its environmental impact. This paper focuses on subsea developments and the offshore power solutions that may allow to reduce associated scope 1 & scope 2 GHG emissions.
As the usual power generation systems based on the use of gas or fuel turbines are a major source of emissions for offshore production, power generation and power sources represented an interesting field of investigations. A series of scenarios for subsea systems was defined, depending on the equipment to be powered (subsea trees, subsea processing, subsea compression…). On the other hand, a preliminary mapping of all potential power sources for an offshore field was built. Then, implementation of such power sources in various subsea schemes have been investigated and associated benefits, limitation and technology requirements have been discussed.
The presented paper allows to get a quick and quite comprehensive overview of the potential schemes to be investigated to decarbonize power generation for subsea fields. It can be used as a high-level guide to start decarbonization investigations for specific study cases, depending on the available resources and development objectives for the field.