bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of Boron-Based Nanomaterial Enhanced Additive in Water-Based Drilling Fluids: A study on Lubricity, Drag, ROP and Fluid Loss Improvement
Authors: Krishnan Shutesh , Abyat Zahra , Chok Calvin 
Published: January 2016

Abstract
The present work focuses on application of boron-based nanomaterial enhanced additive (PQCB) in water based mud system. The additive is specially formulated to improve friction, torque and hydraulic drag in challenging subterranean formations with bottom-hole temperature reaching 200°C. Extreme pressure tests were conducted using the standard 10 lb/gal and 13.5 lb/gal water based muds. For 10 lb/gal mud system addition of 5% of this additive gives torque reduction of 80% while for 13.5 lb/gal mud the torque reduction was 52%. We noticed an increase in rheology of the mud with the addition of this additive showing higher PV, YP and gel strength as compared to the commercially available lubricant. Low RPM rheology for high mud weight formulation showed a two-fold increase. Higher low RPM rheology will improve the drilling-hole cleaning and weighting materials suspension capability. PQCB also shows a consistent HPHT fluid loss control performance in 10 lb/gal and 13.5 lb/gal muds. This is due to its ability to withstand the higher conditioning temperature and prevent early breakdown of the polymers in the mud system. During a field trial in Myanmar at one of the wells with known hard subterranean formation, PQCB demonstrated an excellent performance with torque reduction of 36.36% and return permeability of 41% while the commercial lubricant gives torque reduction of approximately 13.64% and return permeability of 49%. Unlike any other ester based additives, PQCB shows no hydrolysis problem on both the mud systems tested. This enables the elimination of silicone and alcohol based de-foamers in the mud formulation. The nanomaterial enhanced PQCB additive is also biodegradable and helps to prevent the wear and tear of drilling tools that ultimately will reduce the overall production cost.
Managing Risks around Rigs Using Autonomous Marine Vehicles
Authors: Pai Sudhir 
Published: January 2016

Abstract
Obtaining accurate data is an important factor in drilling operations and can have lasting effects on exploration and production objectives. This abstract focuses on the use of autonomous marine vehicles (AMVs), a hybrid sea-surface and underwater vehicle that's capable of crossing thousands of kilometers of ocean to gather oceanographic data, for effective environmental seep surveys, taking meteorological readings while maintaining a stationary position, or circling a rig at a preset distance to provide early warning of security and environmental threats. Once deployed, it uses no crew, requires no fuel and produces no emissions, thus eliminating both risk to personnel and impact on the environment.
1Two AMV's were used to conduct a baseline survey offshore Northwest Australia. Quality data was acquired by the AMV's prior to commencing pipeline dredging work for the construction of two liquefied natural gas (LNG) trains and a domestic gas plant, 12 km west of Onslow on the Pilbara coast.
2A major operator used the AMV equipped with Acoustic Doppler Current Profilers (ADCPs) to aid in operations during a seismic survey in Gulf of Mexico. The AMV was deployed to measure current parameters, and to transmit this data in real-time via satellite to the seismic vessel as the survey was underway.
1The vehicles travelled a total of 1,424 miles over the 60-day mission, waypoint tracking remained stable and there was no lost survey time.
2This information helped the navigators to determine how closely the vessel could pass obstructions in order to minimize infill while at the same time avoiding entangling the streamer on the marine structure.
Both operations were completed in a cost-effective manner, and the vehicle replaced manned vessels, which were deployed for other important navigational challenges on the operation. The survey was optimized without compromising results due to the vehicle's ability to overcome a number of challenges including a significant dust storm which caused bio fouling, limiting data recording times, and a hurricane causing the vehicles to be piloted to a designated holding area. By utilizing AMVs, both operators were able to accurately estimate the uncertainties of a seismic survey, in a remote location in the presence of assets like rigs and process platforms where data was not readily available and to circumvent lost survey time during pipeline dredging operations.
This technology provides persistent ocean presence and a reliable data acquisition platform which can support numerous drilling applications. To date these vehicles have conducted 28 missions in the oil and gas industry with more than 3,100 days at sea. AMV's have proven to be a very cost-effective way to conduct exploration business while managing risks.
Successful Application of Innovative Engineering Approach to Reenter Problematic Reservoirs Leads to Astonishing Results: A Case Study
Authors: Al-Refai I. M. , Gratia P. I. 
Published: January 2016

Abstract
Objectives/Scope: Sidetrack drilling in depleted unconsolidated sandstone reservoirs with overlying reactive shale faces many engineering and operation challenges. Depleted reservoirs require a low mud weight to avoid stuck pipe due to differential sticking. Reactive unstable shale requires a higher mud weight to provide hole stability. Installing sand screens across the reservoir adds additional complication to drilling operations.
Proper planning is key to overcoming drilling challenges. Planning includes selection of well design, directional trajectory planning and mud selection. The selection of casing design depends on reservoir pressure and logging requirements. The requirement for a dual lateral completion also affects the hole configuration. The optimum kickoff point, maximum dog leg severity, inclination across the shale zone, shale footage and trajectory azimuth play important roles in the success of sidetracking operations. Mud weight and mud rheology are thoroughly planned and closely monitored during the operations. Drilling with a rotary steerable Bottom Hole Assembly (BHA) and deploying sand screen completion, such that it reduces chances of differential sticking, are also critical parts of the planning.
Many wells have been successfully sidetracked and completed to meet reservoir management objectives. The casing design of reentry wells has evolved from two (2) hole sections to one (1) hole section and has saved 32% of the drilling time and has reduced the well cost by 23%. Appropriate well direction (azimuth) and correct mud weight related to maximum or minimum stress direction have been identified utilizing special geomechanics software. The salinity of an oil-based mud (OBM) is critical while drilling through reactive shale. Water activity tests on shale samples is used to design the proper OBM and special monitoring protocols were established to ensure the rheology of the OBM. A modified sand screen completion has been proven to reduce the potential occurrence of stuck pipe.
Most of key factors in planning can be applied in all wells to some extent. Each well is uniquely based on its subsurface targets and reservoir pressure.
3D Offset Well Analysis in Petrel
Authors: King Emma , Dwyer Jean , Ilett Thomas , Houette Olivier , Gunawan Henny , Correa Juan , Lepp Becky , Tawakol Mohamed , Blasdale Tim 
Published: January 2016

Abstract
Prior to undertaking any drilling campaign, the process of offset well analysis is of paramount importance. When performed accurately and presented properly it provides the basis for all design work and risk analysis.
A new feature in the modelling software Petrel called Drilling Risk Manager offers the ability to be able to carry out the offset well analysis in a 3D environment.
The aims of this study is to investigate the means in which the Drilling Risk Manager feature of Petrel can aid in de-risking wells during the offset well analysis process and to highlight the potential efficiency savings that can arise.
The efficiency savings of using Petrel have been highlighted through the use of a case study focusing on the initial development work that was carried out in conjunction with TAQA for their North Cormorant and Cormorant East fields in the UK continental shelf. In this study a Schlumberger engineer worked closely with TAQA on classifying the offset well data for the field, populating the data into a 3D shared earth model in Petrel and then using this model to perform a full risk analysis.
For TAQA, using Petrel has made it easier to clearly view all of the drilling hazards that have occurred on the North Cormorant and Cormorant East fields. Using all of the extra information, two wells drilled on the Cormorant East field were well prepared for hazards which are common in the area. Using the 3D model to aid in the risks analysis process saved a considerable amount of time in comparison to the usual method employed by TAQA.
Schlumberger are in the process of fully developing the use of Petrel as a means of derisking wells in mature fields in to a value added service that can be provided throughout a drilling campaign. Projects are being developed for several UK Operators in this field, incorporating well bore stability and drilling analysis in order to provide efficiency savings throughout a drilling campaign.
Pressure-Transient Analysis of a Finite-Conductivity Inclined Fracture Connected to a Slanted Wellbore
Authors: Jia Pin , Cheng Linsong , Huang Shijun , Liu Hongjun 
Published: January 2016

Summary
The principal focus of this work is on pressure-transient analysis of a finite-conductivity inclined fracture connected to a slanted wellbore, on the basis of a semianalytical model. Detailed analysis of unsteady-state pressure behavior of a fully penetrating inclined fracture in an infinite-slab reservoir was provided. The study has shown that a finite-conductivity inclined fracture may exhibit five flow regimes: bilinear flow, formation linear flow, early radial flow, compound linear flow, and pseudoradial flow. The characteristics of bilinear flow and formation linear flow are predominantly determined by fracture conductivity. In the case of a low formation-thickness/fracture-half-length ratio and small inclination angle, both early radial flow and compound linear flow may be absent. Analytical solutions for transient responses during different flow regimes are similar to that for a fully penetrating vertical fracture and can be correlated with the cosine of fracture-inclination angle with consideration of permeability anisotropy. Effect of inclination angle and reservoir-permeability anisotropy on transient responses is strong, which extends to pseudoradial-flow period. Formation thickness mainly influences the middle to late flow periods. In addition, the pseudoskin factor is also investigated in detail.
Evaluating the Value of Single-Point Data in Heterogeneous Reservoirs With the Expectation-Maximization Algorithm
Authors: Nakayasu Masahiro , Goda Takashi , Tanaka Kei , Sato Kozo 
Published: January 2016

Summary
A better characterization of reservoir heterogeneity is indispensable to improve the prediction accuracy on production performance of heterogeneous petroleum reservoirs. Measuring physical properties at a single point can provide us with local information on reservoir heterogeneity, which is also beneficial in reducing some degree of uncertainty about global reservoir heterogeneity, and thus leads us to an improved prediction accuracy. It is not necessarily the case, however, that an improvement of the prediction accuracy implies an increase of our ability to make a proper decision. In this paper, we discuss how to quantify such a value of single-point data, obtained by measuring physical properties at a single point, for decision making in development of heterogeneous reservoirs by using the value-of-information (VOI) theory. We present an efficient algorithm to evaluate the value of single-point data with the help of reservoir simulation, Gaussian random field models, Monte Carlo integration, and the expectation-maximization (EM) algorithm. We validate our algorithm through a toy problem, and then demonstrate the practical usefulness of our algorithm through numerical experiments.
Die Rolle von Eiche, Totholz und Efeubeeren bei der Habitatwahl des Mittelspechts
Authors: Spühler Lisa , Krüsi Bertil O. , Pasinelli Gilberto 
Published: January 2016

The role of oak, deadwood and ivy for habitat selection of the middle spotted woodpecker
Due to their habitat needs, woodpeckers are generally considered to be excellent indicators of forest habitat quality and biodiversity. In the EU and in Switzerland, the middle spotted woodpecker acts as a flagship species for nature conservation in forests. After several decades of decline in the Canton of Zurich, the population of the indicator species more than doubled between 2002 and 2012. The reasons for this positive development are so far unknown. It is hypothesized that an increased availability of ivy berries, sometimes eaten by the middle spotted woodpecker, may have contributed to the population growth. Based on the woodpecker monitoring 2012 in the Canton of Zurich, in 2013 the availability of trees with ivy berries at sites with and without presence of the middle spotted woodpecker was examined in eight forests. At the same time we also studied the availability of oaks and standing dead trees, two habitat factors well known to be important for the middle spotted woodpecker. Results revealed significantly shorter distances to large oaks and a tendency towards shorter distances to dead trees at points with middle spotted woodpecker presence than at points without. The distance to trees with ivy berries, on the other hand, was the same at presence and absence points. Occurrence probability of the middle spotted woodpecker was best explained by the distances to the closest large oak and to the closest standing dead tree, respectively. The importance of ivy contributing to the structural diversity in forest ecosystems and providing food and refuge to many species is widely recognized. Therefore, ivy should not be eliminated and oaks and dead trees should be continued to be fostered.
Sustained Immune Control in HBeAg-Positive Patients who Switched from Entecavir Therapy to Pegylated Interferon-α2a: 1 Year follow-up of the OSST Study
Authors: Han Meifang , Jiang Jiaji , Hou Jinlin , Tan Deming , Sun Yongtao , Zhao Mianzhi , Ning Qin 
Published: January 2016

Background In the OSST study, hepatitis B e antigen (HBeAg)-positive chronic hepatitis B patients who switched from long-term entecavir (ETV) therapy to pegylated interferon-α2a (PEG-IFN-α2a; 40 kDa) achieved higher rates of HBeAg seroconversion and hepatitis B surface antigen (HBsAg) loss than those who continued ETV. Herein we report the sustainability of serological responses during 1 year of untreated follow-up in patients who switched from ETV to PEG-IFN-α2a therapy. Methods A total of 62 patients who completed 48 weeks of PEG-IFN-α2a therapy were followed-up for 48 weeks off treatment. Primary end points were HBeAg seroconversion and maintenance of HBeAg seroconversion at 48 weeks post-treatment. Secondary end points included HBsAg loss, HBV DNA <1,000 copies/ml and alanine aminotransferase normalization (<1 x upper limit of normal). Results The HBeAg seroconversion rate increased from 17.7% (11/62) at the end of treatment to 38.7% (24/62) 1 year post-treatment. Sustained HBeAg seroconversion was achieved by 63.6% (7/11) patients with end-of-treatment responses, while late HBeAg seroconversion was achieved by 33.3% (17/51) of patients who did not have end-of-treatment responses. Sustained HBsAg loss was documented in 6 of 7 patients, and sustained HBV DNA suppression was achieved in 60% (27/45) of patients with an end-of-treatment response. Conclusions In patients who do not achieve HBeAg sero-conversion during long-term ETV therapy, switching to finite treatment with PEG-IFN-α2a produces HBeAg sero-conversion in a substantial proportion of patients at end of treatment and during 1 year of follow-up. Moreover, HBeAg seroconversion and HBsAg loss are sustained in most patients during 1 year of untreated follow-up.
L’être en relation thérapeutique en analyse transactionnelle : La vérité de l’amour ou l’amour de la vérité
Authors: Bonds-White Frances , Bailleau Patrick 
Published: January 2016

Les années 1990 ont vu s’opérer un glissement dans les théorisations cliniques au sein des approches psychodynamiques orientées sur le Moi, dont l’analyse transactionnelle. L’interprétation et l’insight ne sont plus considérés comme les moyens premiers du changement thérapeutique. Des thérapeutes de nombreuses et différentes orientations théoriques mettent dorénavant l’accent sur les composantes relationnelles, transférentielles et contre-transférentielles du processus thérapeutique. La littérature clinique est submergée par les modèles et le langage relationnel : processus mutuel, empathie, accordage, attachement, environnement « holding », relations d’objet, connaissance relationnelle implicite, intersubjectivité, réciprocité, synchronicité émotionnelle, connexion, moment de rencontre et résonance. Ce « zeitgeist » 2 relationnel a été renforcé par la popularité des modèles centrés sur la féminité tel que le modèle relationnel développé au Stone Center du Wellesley College et les approches centrées sur le traumatisme qui, tous les deux, mettent l’accent sur le rôle relationnel actif, maternant et correctif du thérapeute. Alors que ces approches maternantes/relationnelles ont beaucoup fait pour corriger les styles unidirectionnels, paternalistes et autoritaires qui prévalaient dans la psychanalyse classique et dans les orientations cognitives et comportementalistes, nous voyons apparaître maintenant dans l’analyse transactionnelle contemporaine des applications aveugles de divers modèles relationnels qui pourtant, selon nous, mériteraient une critique sérieuse.
Les demandes de facteurs de production en France
Authors: Ducoudré Bruno , Plane Mathieu 
Published: January 2016

Avec la crise débutée en 2008, les facteurs de production ont connu en France une contraction sans précédent depuis la Seconde Guerre mondiale. La crise se caractérise par sa longueur : sept ans après son commencement, les facteurs de production n’ont toujours pas retrouvé leur niveau d’avant-crise. Face à un tel choc, il s’agit de savoir si, au regard de la crise, les ajustements opérés sur les facteurs de production sont en lien avec les évolutions de l’activité et si la crise a entraîné des ruptures dans le comportement des entreprises. Pour répondre à cette question, nous estimons d’une part des équations de demandes de facteurs sur les périodes 1980-2007 et 1980-2014 et nous analysons et comparons les paramètres estimés sur ces deux périodes. D’autre part, nous réalisons des simulations dynamiques de l’emploi et de l’investissement que nous comparons aux évolutions observées de ces deux variables, afin d’établir si les déterminants traditionnels des équations permettent de comprendre les évolutions des facteurs de production depuis le début de la crise. Concernant la tendance de productivité, nous conduisons des tests de détection et de datation des ruptures de tendance de productivité, ainsi que des estimations récursives des paramètres. Les résultats des équations économétriques n’indiquent pas de rupture majeure au moment de la crise dans les déterminants fondamentaux de l’investissement et de l’emploi. Enfin, nous exposons les propriétés variantielles des deux équations de demande de facteurs, puis nous évaluons l’impact depuis 2011 des politiques de consolidation budgétaire dans la zone euro et de la dégradation du taux de marge des entreprises sur l’emploi salarié marchand et le stock de capital productif en France. Toutes choses égales par ailleurs, les politiques de consolidation budgétaire dans la zone euro seraient, selon nos évaluations, responsables en France de la destruction de 772 000 à 822 000 emplois salariés dans le secteur marchand et d’une chute de l’investissement des entreprises non-financières comprise entre 6,8 % et 7,6 %, soit une contraction de 1,6 % à 1,7 % du capital productif. La baisse du taux de marge depuis 2011 aurait conduit à réduire l’investissement des entreprises de 2,1 % à 2,5 %, ce qui correspond à une baisse du capital productif de 0,3-0,4 %.
La crise de 2008 et la productivité totale des facteurs des entreprises françaises
Authors: Guillou Sarah , Nesta Lionel 
Published: January 2016

Nous mesurons la productivité totale des facteurs (PTF) de plus de 2 millions d’entreprises françaises entre 2002 et 2011, réparties en 6 grands secteurs : manufacturier, construction, services de basses et moyennes technologies, services de hautes technologies, autres services, services financiers et immobilier. Nous observons que la crise s’est traduite par une baisse transitoire de la PTF, à l’exception des services de hautes technologies ou de la construction. Les plus grandes entreprises ont des niveaux de productivité plus élevés et ont mieux résisté à la crise de 2008. La crise a stoppé les effets d’apprentissage des firmes, si bien que le peu de croissance (de la TFP) observé après 2008 vient des phénomènes de réallocation des ressources entre entreprises. Enfin, la crise de 2008 a significativement altéré la corrélation entre investissement et croissance de la PTF, l’investissement post-2008 étant associé à un ralentissement de la croissance de la PTF. Des changements de la nature des investissements tout autant que des effets de volume peuvent expliquer l’inefficacité de l’investissement après la crise.
France et Allemagne : une histoire du désajustement européen
Authors: Le Moigne Mathilde , Ragot Xavier 
Published: January 2016

La divergence économique entre la France et l’Allemagne depuis 1993 est impressionnante. Alors que les deux pays étaient dans des situations comparables à la fin des années 1990, l’Allemagne est aujourd’hui au voisinage du plein emploi – en dépit d’inégalités en hausse – et est devenue l’un des pays les plus exportateurs du monde. La France connaît un niveau de chômage historique et voit ses performances commerciales se dégrader continûment. Plusieurs explications à cette divergence ont été proposées. Cet article quantifie la contribution particulière de la modération salariale allemande débutant outre-Rhin au milieu des années 1990 sur l’écart de performances économiques franco-allemand. En effet, les salaires allemands sont restés extraordinairement stables après la réunification allemande, et ce essentiellement dans les services. À l’aide d’un modèle quantitatif de commerce international, nous estimons que la modération salariale allemande est responsable de l’ordre de la moitié de l’écart de performances à l’exportation de la France par rapport à l’Allemagne, et explique environ 2 % du taux de chômage français. Le problème de l’offre en France est essentiellement le résultat du désajustement européen.