bluuebunny/crossref_metadata_2025_split huggingface dataset:
Exploring the Effects of Disk Thickness on the Black Hole Reflection Spectrum
Authors: Taylor Corbin , Reynolds Christopher S. 
Published: March 2018

Abstract
The relativistically broadened reflection spectrum, observed in both AGN and X-ray binaries, has proven to be a powerful probe of the properties of black holes and the environments in which they reside. Emitted from the innermost regions of the accretion disk, this X-ray spectral component carries with it information not only about the plasma that resides in these extreme conditions, but also the black hole spin, a marker of the formation and accretion history of these objects. The models currently used to interpret the reflection spectrum are often simplistic, however, approximating the disk as an infinitely thin, optically thick plane of material orbiting in circular Keplerian orbits around the central object. Using a new relativistic ray-tracing suite (Fenrir) that allows for more complex disk approximations, we examine the effects that disk thickness may have on the reflection spectrum. Assuming a lamppost corona, we find that finite disk thickness can have a variety of effects on the reflection spectrum, including a truncation of the blue wing (from self-shadowing of the accretion disk) and an enhancement of the red wing (from the irradiation of the central “eye wall” of the inner disk). We deduce the systematic errors on black hole spin and height that may result from neglecting these effects.
Accurate Ray-tracing of Realistic Neutron Star Atmospheres for Constraining Their Parameters
Authors: Vincent Frederic H. , Bejger Michał , Różańska Agata , Straub Odele , Paumard Thibaut , Fortin Morgane , Madej Jerzy , Majczyna Agnieszka , Gourgoulhon Eric , Haensel Paweł , Zdunik Leszek , Beldycki Bartosz 
Published: March 2018

Abstract
Thermal-dominated X-ray spectra of neutron stars in quiescent, transient X-ray binaries and neutron stars that undergo thermonuclear bursts are sensitive to mass and radius. The mass–radius relation of neutron stars depends on the equation of state (EoS) that governs their interior. Constraining this relation accurately is therefore of fundamental importance to understand the nature of dense matter. In this context, we introduce a pipeline to calculate realistic model spectra of rotating neutron stars with hydrogen and helium atmospheres. An arbitrarily fast-rotating neutron star with a given EoS generates the spacetime in which the atmosphere emits radiation. We use the Lorene/nrotstar code to compute the spacetime numerically and the Atm24 code to solve the radiative transfer equations self-consistently. Emerging specific intensity spectra are then ray-traced through the neutron star’s spacetime from the atmosphere to a distant observer with the Gyoto code. Here, we present and test our fully relativistic numerical pipeline. To discuss and illustrate the importance of realistic atmosphere models, we compare our model spectra to simpler models like the commonly used isotropic color-corrected blackbody emission. We highlight the importance of considering realistic model-atmosphere spectra together with relativistic ray-tracing to obtain accurate predictions. We also insist upon the crucial impact of the star’s rotation on the observables. Finally, we close a controversy that has been ongoing in the literature in the recent years, regarding the validity of the Atm24 code.
Du paganisme au christianisme en Normandie occidentale ( iv e - v e siècles) : premiers éléments de synthèse
Authors: Roupsard Mathilde 
Published: March 2018

Cet article reprend une étude de synthèse effectuée pendant deux années dans le cadre d’un travail universitaire. Il porte sur la période de transition entre le paganisme et le christianisme comprise entre le iv e et le vi e siècle. À partir d’une analyse croisée de sources de natures variées, plusieurs thématiques ont pu être abordées : la chronologie de la transition entre le paganisme et le christianisme, l’étude architecturale et fonctionnelle des lieux de culte, et enfin, l’environnement d’implantation des sites cultuels et funéraires. Cela a permis d’établir des conclusions sensiblement différentes des postulats dominants jusqu’à maintenant. Le schéma d’un désintérêt progressif et largement pacifique du paganisme dès le iii e siècle a été dégagé. Parallèlement, l’implantation très progressive, superficielle et largement urbaine du christianisme, en grande partie sous l’impulsion des premiers clercs, soutenus par l’autorité royale, a pu être observée tout au long de la période considérée.
Le Maître de Caen et la production enluminée en Normandie occidentale au début du XV e siècle
Authors: Chenu Rachel 
Published: March 2018

Première étude consacrée à la production enluminée en Normandie occidentale au xv e siècle, cet article consacré à l’œuvre enluminée du Maître de Caen ne se contente pas de mettre au jour une production locale destinée à la petite noblesse et à la bourgeoisie de province. Il offre également un aperçu de la circulation des modèles, des artistes, des œuvres et des commanditaires en Normandie, sous l’occupation anglaise.
Retour sur le parcours d’Eugène Maës, promoteur de sports aquatiques à Caen
Authors: Auvray Emmanuel 
Published: March 2018

À Caen, le nouveau Stade nautique nouvellement dénommé, en 2014, Eugène Maës (1890-1945) pose la question de l’histoire locale du développement des sports aquatiques et de la mémoire collective de ceux qui ont fréquenté l’établissement « Chez Maës, Au Lido ». Cette étude historique vise donc à identifier les éléments du cheminement biographique d’Eugène Maës qui, d’une guerre à l’autre, ont conduit le conseil municipal de Caen à adopter ce choix pour honorer la mémoire d’un animateur de la vie sociale et sportive caennaise mort en déportation en 1945. Eugène Maës, footballeur de renom, a amorcé localement le développement de la natation sportive et du water-polo, contribué à sauver des vies en apprenant à nager à de nombreuses personnes, favorisé, dans le tissu associatif local, les conditions d’un brassage social par le biais de manifestations spectaculaires et originales, et enfin, permis aux Caennais de venir danser et écouter du jazz dans son café-dancing « Au Lido ». Ce choix constitue aussi un acte politique républicain contre l’oubli des victimes du nazisme.
Empirical study on the integrated management system in Algerian companies
Authors: Benyettou Samiya , Abdellatif Megnounif 
Published: March 2018

Purpose: The integrated management system concept has been installed recently in Algerian companies. A theoretical model is proposed which is based on a functional analysis of the systemic approach. This model is a cycle of seven requirements (organization context, leadership, planning, support, implementation of operational activities, performance evaluation and improvement), in addition to the inputs and outputs. The purpose of this article is to investigate the current status of integrated management system and test its performance in Algerian CompaniesDesign/methodology/approach: In order to achieve this objective, a survey based on 250 companies, only 115 of them responded to the survey where half of them are implementing IMS. A descriptive and an exploratory factor analysis (EFA) are provided. Additionally, the confirmatory Factor Analysis (CFA) the correlation and the regression analyzeFindings: From the results, the research reflects the status of IMS in Algeria. The findings suggest that the Algerian company have difficult to implementing the IMS. Research limitations/implications: One of the major limitations of this study is the small simple size, which precludes generalization of the findings. This study provides a starting point for further research in developing countries.Originality/value: This paper offers first key insights into IMS implementation in Algeria. This will encourage these organizations and developed countries in adopt IMS.
Clavardage pédagogique : performances en écriture et interactions entre pairs chez des élèves du secondaire en difficulté d'apprentissage
Authors: Gonthier Marie-Ève , Ouellet Chantal , Lavoie Natalie 
Published: March 2018

Bien que fort populaire chez les jeunes d'aujourd'hui, le clavardage semble peu utilisé en classe. Cet article fait état d'une recherche qualitative centrée sur l'utilisation du clavardage pédagogique en contexte d'écriture, dont les objectifs sont les suivants : 1) analyser et comparer un texte rédigé individuellement à l'ordinateur et un texte écrit en collaboration avec le clavardage, 2) analyser les interactions lors des séances de clavardage et 3) les mettre en lien avec les textes produits. Les scripteurs (N = 20) et leurs équipiers (N = 20), qui les ont soutenus avec le clavardage pour le second texte, sont des élèves en difficulté de première et de deuxième secondaire (12-14 ans). Les textes ont été analysés d'après différents critères et les interactions ont été classées dans des catégories. Il a aussi été vérifié dans quelle mesure les propositions des pairs ont été transférées dans les textes. Grâce au clavardage, les jeunes des deux niveaux ont mieux réussi à certains critères d'évaluation (orthographe grammaticale, respect des consignes et construction des phrases). Les interactions cognitives centrées sur la tâche dominent dans leurs discussions ; d'ailleurs, ils ont pris en compte plus de la moitié des propositions discutées. En somme, les jeunes ayant un intérêt certain pour le clavardage, il demeure judicieux d'y faire appel afin d'écrire en classe.
The Operational Benefits of 30-in. Casing While Drilling CwD Conductor Installation
Authors: Roy C. H. , Frederick A. T. , Thibodeaux J. J. 
Published: March 2018

Abstract
The paper reports a best-practices case study regarding the Casing-while-Drilling (CwD) installation of large outer-diameter (OD) tubulars—30-inch casing, specifically—in a troublesome zone in Campeche Bay, Mexico. The 30-in. CwD job was an industry first for this pipe size. The installation was an ambitious attempt to drill a 30-in. conductor in an area historically fraught with extreme wellbore instability and to produce better results than conventional drilling could deliver.
Another objective was to push the 30-in. conductor to a depth that had been unattainable in previous instances of comparable lithology. Hammering was too disruptive for such a precarious formation, and conventional drilling, with its manual equipment and serial tripping, was too time-consuming, making well collapse probable. CwD, therefore, was the best option.
The CwD process entailed a 30-in. Casing Running Tool (CRT) with hydraulic pick-up arms and a remotely operated Single Joint Elevator (SJE) handling the casing, the first joint bearing a 34-in. drillbit. In one run, the 30 × 34-in. conductor section was drilled, cased, and cemented at a total depth of 256m—78m reaching/jetting into seabed, 178m drilling. The job only took 9.52h, with an average Rate of Penetration (ROP) of 18.04m/h, and drill-time was reduced by 1.31d (26.3%) when compared to conventional drilling. And there were no stuck pipe issues, problems while tripping in the hole, or safety incidents.
Successful completion of the well hinged on the CRT's multi-functionality and capacity for running large-OD tubulars. Filling, or pumping, the string while lowering served as a lubricator, evacuating cuttings more effectively and resolving the hole-cleaning inefficiencies experienced in adjacent wells. The improved running efficiencies were also realized due to the hydraulic arms enabling better control of pipe movement; more specifically, the operational benefits of superior handling of large-OD pipe were three-fold.
First, rotation of the string enhanced the plaster/smear effect, strengthening the wellbore, averting lost circulation, and minimizing formation damage. Second, the large casing-to-wellbore diameter ratio created a gauged well, the smoother, more circular profile contributing to better well stability and requiring less cement. Third, a small, mono-bore annulus (between wellbore and casing) and consequent higher annular velocity facilitated cutting transport, prevented wellbore erosion, and resulted in hydraulic optimization while running 256m of conductor.
Impact of Injection Scenario on CO2 Leakage and CO2 Trapping Capacity in Homogeneous Reservoirs
Authors: Al-Khdheeawi Emad A. , Vialle Stephanie , Barifcani Ahmed , Sarmadivaleh Mohammad , Iglauer Stefan 
Published: March 2018

Abstract
The impact of different injection scenarios on the vertical CO2 leakage and on the capacity of CO2 storage in homogeneous reservoirs has been systematically investigated by comparing the total vertical CO2 plume migration distance, the amount of free CO2 and the capacities of capillary and solubility trapping obtained. A 3D homogeneous reservoir simulation model has been developed to simulate a CO2 plume behavior for three different injection scenarios (water alternating CO2 (WACO2) injection, periodic injection and standard continuous CO2 injection). The injection period was 20 years and the total amount of injected CO2 was 20 Mton, for all injection scenarios. Then, after the end of the injection period, a storage period of 200 years was simulated. We then compared the CO2 leakage and the amount of free, dissolved and trapped CO2 between these three injection scenarios. The results show that, after 200 years CO2 storage period, injection scenario significantly affects the vertical CO2 leakage and the CO2 trapping capacities in homogeneous reservoirs. Firstly, our results show that the standard continuous CO2 injection and periodic injection scenarios lead to increase the CO2 mobility and vertical CO2 leakage. In addition, the simulation results show that the amount of CO2 trapped (by both residual and solubility trapping) in the standard continuous CO2 injection scenario is less than that trapped in the other injection scenarios. Thus, we conclude that injection scenario has an important effect on the CO2 sequestration processes.
Rapidly Rig Installable and Re-Usable Suction Bucket Wellhead Platforms
Authors: Deeks Andrew , Gaunt Peter , Torgersrud Øyvind , Boylan Noel , O'Leary Darren , Field David 
Published: March 2018

Abstract
A combined offshore jacket structure and foundation concept is presented, which is installable from a jack-up drilling rig. This novel system integrates the various components with extensive track record in both the offshore oil & gas and windfarm industries. It is founded on suction buckets that use water underpressure to drive installation of the foundation. It is rapid and quiet to install and re-usable; utilising the same jack-up that will be drilling and/ or abandoning the wells to perform the installation/relocation. The scope of the paper is to present the technical aspects of installation, structural and foundation engineering necessary for successful development of such facilities. This includes consideration of interaction between the structure and jack-up during both installation, but also during operation (work-over) and re-use.
Well Design for Methane Hydrate Production: Developing a Low-Cost Production Well for Offshore Japan
Authors: Yamamoto Marcio , Miura Kazuo , Wada Ryota , Takagi Ken 
Published: March 2018

Abstract
The key word for the production development of offshore methane hydrate reserves is "Low-cost". In this article, we propose the design of a subsea production well that could be deployed at the Nankai Trough, offshore Japan. Instead the traditional drillship, we intend to use a combination of three specialized vessels: (i) top-hole drilling vessel, (ii) well intervention vessel equipped with Coiled Tubing Unit and (iii) subsea equipment support vessel. These three specialized vessels have cheaper daily rates than a single last generation drillship. Keeping the limitations of such vessels in mind, we propose a well with a top-hole composed only by the surface casing. Further, we intend to use the "coiled tubing drilling" technology to drill-in, what shall reduce the operational time. Then a liner could be used as interface with the reservoir. In terms of completion, the methane shall be produced by the annular and a tubing shall be installed to remove the water from the well bore using a pump that is installed outside the well. Such arrangement makes the installation and maintenance of the pump easier because the equipment can be replaced without the need of a heavy workover.
Summarizing, the use of specialized vessel in distinct phases of the well construction may reduce the cost in 2 ways: cheaper daily rates than a traditional drilling and reduced operational time due to specialization itself (reduced time for rig up/down of equipment for distinct phases). Further, the use of coiled tubing and a simple completion shall reduce the operational time and equipment costs.
Innovative Noise Analysis Modeling Scheme Produces Results in Half the Time of the Traditional Method
Authors: Zhu Ruiyi , Wooi Theam KoK , Xu Dong , Wu Jer-Fang 
Published: March 2018

AbstractBecause noise issues onboard marine and offshore structures can adversely affect the performance and health of crew members, the subject has gained increasing attention in recent years. Noise analysis is necessary to improve acoustic design and mitigate inappropriate noise.The innovative modeling scheme for noise analysis presented in this paper focuses on simplifying the noise modeling method. Case studies were conducted for an anchor handling tug supply (AHTS) vessel (Nam Cheong Limited 1st design project NCA80E – 64.8m 80t AHTS DE) and an 80,000 deadweight long-range product tanker to demonstrate the simplified modeling method. Noise analysis results were compared with the measurement data to validate the proposed method.Two models – including the whole vessel model and the simplified model, comprising only part of the vessel encompassing the accommodation block and engine room area – were analyzed under transit conditions using the statistical energy analysis (SEA) software Designer Noise. The analysis accounted for multiple noise paths from major noise and vibration sources, including airborne path, first structure-borne path, and secondary structure-borne path. The primary structures, compartments of interest, and outfitting were modeled to calculate the sound attenuation from the sources to the receiver rooms.Differences in the case study analysis results, calculated using the entire vessel model and the simplified model, are 0.03 dB for the AHTS and 0.17 dB for the tanker, which is negligible. Moreover, the analysis results of the simplified model are all higher than those of the entire model, which indicates that the simplified method is slightly on the conservative side. By comparing the analysis results of the simplified model with the actual measured noise levels of the AHTS for a total of 35 sites, it is found that 51.4% of the sites are within 3 dB, and 28.6% of the sites are within 3-5 dB, while only 20 % of the sites are larger than 5 dB. By comparing the analysis results of the simplified model with the actual measured noise levels of the tanker for a total of 48 sites, it is found that 60.4 % of the sites are within 3 dB, and 29.2% of the sites are within 3-5 dB, while only 10.4 % of the sites are larger than 5 dB.The proposed method can reduce the modeling time of the main hull by approximately 50% while still maintaining comparable accuracy.
CO2 Direct Utilization Technology for Economic Development of High CO2 Gas Field: A Technology Assessment Study
Authors: Lahuri H Mumtaz , Seman Akbar A , Berahim N Hafizah , Onn M Syazwan , Nor M Ghaddaffi M 
Published: March 2018

Abstract
Permanent abatement of CO2 has become a major challenge in many gas field developments especially within this South –East Asia region. Among the challenges are on how to dispose or utilize this huge amount anthropogenic CO2 safely and economically. Therefore, the objective of this study is to identify the best technology for non-catalytic CO2 Direct utilization to manage and support economic development of high CO2 gas field in Malaysia. A Market survey was conducted to a few shortlisted technologies to assess on the technology landscape and the market potential. The feedback was analyzed based on the criteria established on the basis of company requirement. From the study, ‘Mineral Carbonation’ has been identified as one of the potential technology solution for permanent sequestration of CO2 in Malaysia. The future of this technology application is very promising due to the availability of the local feedstock, mineral waste and the potential market of this product especially for carbonate product such as precipitated calcium carbonate (PCC). However, this technology still possesses some technical challenges due to slow kinetic reaction. For a large scale application, this will become more demanding especially in terms of footprint as the current technology is mainly on batch process. Therefore, the current R&D should look into area where this process kinetic can be improved and to look into continuous or semi-continuous process for smaller footprint.
Development of Technologies of Floating LNG Bunkering Terminal and Assessment of Safety and Performance
Authors: Kim Y. , Cho S. , Jung D. , Sung H. , Hong J. , Jung S. 
Published: March 2018

Abstract
The concept of Floating LNG Bunkering Terminal (FLBT) has been developed for offshore bunkering services in Korea. FLBT which has a 220k m3 storage capacity is under developing, which can receive LNG from LNG carriers or transfer LNG to LNG bunkering shuttles at sea. FLBT is consisted of the hull, the mooring system and equipments including the berthing system, the ship-to-ship transfer system. As the safe LNG transfer operation is the most essential point for this facility, a series of experiments was performed in order to verify the operational safety of LNG loading and unloading operations at ocean environment.
The preliminary design includes FLBT hull design, operational site, requirements, side-by-side and turret mooring system, and LNG transfer process. Experiments of ship-to-ship mooring configurations were performed in the ocean engineering basin of Korea Research Institute of Ships and Ocean engineering(KRISO). Experimental results were reviewed with aspect to motion responses of floaters, tensions at the ship-to-ship mooring system, and relative motions between LNG loading arms and corresponding manifolds.
In the experiments, the loads on the ship-to-ship mooring system did not exceed their maximum breaking loads, while motion responses of bunkering shuttles were relatively large. The experimental results will be also analyzed in terms of the reliability of ship-to-ship mooring lines and the applicability of a conventional rigid LNG loading arm. Finally, the design will be updated continuously with the conceptual development of FLBT and the feedback from the stability check.
Applications of Hydrocarbon Prediction in Malaysian Offshore Using a New Attribute in Place of Conventional AVO Fluid Factor
Authors: Changcheng Liu , Ishikura Kazuki , Hermana Maman , Sum Chow Weng , Ghosh Deva Prasad 
Published: March 2018

Abstract
Seismic interpretation is one of key steps in the hydrocarbon predication. However, amplitude interpretation using post-stack data is ambiguous because P-wave, S-wave velocity and density can be given by different rock case. A high-porosity brine-filled rock can produce a response same as a mid-low-porosity and hydrocarbon-filled rock as shown in Figure 1.