bluuebunny/crossref_metadata_2025_split huggingface dataset:
Maintain Objectivity To Push Through Transitions
Authors: Duncan Andrew 
Published: February 2016

Discover a Career
If I had a time machine, would I travel back in time to change anything if I could do it again? Should I have taken that job offer as a public relations guy on a treasure-hunting dive boat in the Philippines? No, I do not think so. All experience makes us who we are, and some say they would not change a thing. On the other hand, if I have to change one thing I would have striven harder to learn the languages of the countries in which I have previously worked and would recommend the same to anyone with similar opportunities. I also recommend pursuing variety in one’s career. Change brings opportunities and challenges. Only through change, is progress possible.
When I was growing up in northern Canada, we were offered career advice in high school to learn a trade and work as a welder, truck driver, or get a job on the rigs. I did not feel these career options suited me as I was thinking in terms of further education and I have always enjoyed traveling. Hence, weighing both of these, I decided to pursue a university degree abroad. Since then, I completed my university studies, joined the oil and gas industry, and have enjoyed a diverse career overseas.
Throughout my career transitions, maintaining objectivity has been the most recurring challenge I have dealt with. Through experience, I have learned an important rule when it comes to expatriate life (which applies equally to other career transitions): Never make career-altering decisions in the first 6–12 months after moving to a new country or taking up a new role. It is human psychology to feel excited and motivated about any new location or job immediately after arrival. However, after about 6 months a period of negativity (or reality) sets in and one begins to see only the downside of a new position or new location. My experience suggests that the period of negativity does pass, and when it does, the experience can be truly objective—bringing the positive and useful aspects of past experience to bear while learning and experiencing the best that a new role has to offer.
Over my career, I have gained a lot through changes in my role, career path, or location. Changes in setting can often provoke one to become more open, a better listener, and more patient. I have learned the importance of clear communication and that “communication” involves explaining, listening, and confirming that both parties truly understand both directions.
E&P Notes (March 2015)
Authors: Jacobs Trent , Betz Jack 
Published: February 2016

E&P Notes
Pushing the Limits of Deepwater Stimulation
Trent Jacobs, JPT Technology Writer
The lower tertiary formation found in the pre-salt layers of the Gulf of Mexico has become a proving ground for extending what is possible when completing multistage fracturing in ultradeepwater wells. The stimulation vessels that pump fracturing fluids, acids, and proppant into these wells are key to achieving the volume of production needed to make them profitable.
Baker Hughes operates one of the industry’s youngest fleets of such vessels in the North Sea and offshore west Africa, Brazil, and Vietnam. But because of the strength of lower tertiary rocks and the pressure required to improve contact between the well and the formation, some of the company’s newest and most advanced vessels are reserved for the Gulf.
Automation Program Looks Outside Industry for Inspiration
Jack Betz, JPT Staff Writer
The University of Texas at Austin (UT) will launch an initiative in April to promote cross-discipline collaboration and student research on automated technology in the oil field.
Called Rig Automation and Performance Improvement in Drilling (RAPID), the initiative will enrich UT’s existing drilling research by connecting petroleum-oriented researchers with other engineers and scientists in disciplines outside the oil and gas industry, which have benefited from sophisticated automation. These fields include aerospace, mechanical engineering, and computer engineering.
Dual-Gradient Drilling Debuts in Gulf of Mexico
Jack Betz, JPT Staff Writer
Statoil has successfully used dual-gradient drilling for the first time ever in the US Gulf of Mexico (GOM) on an upper-hole section.
During the trial, Enhanced Drilling’s EC-Drill system successfully maintained a desired bottomhole pressure by controlling mud volume in the riser and the rate of its return to the surface. The technique is called controlled mud level.
“We drilled for about 10,000 ft on the first [GOM] well, and the system ran for 600 hours,” said John-Morten Godhavn, a managed pressure drilling specialist at Statoil, at a recent SPE Gulf Coast Section event.
Unconventional Proppant Combined With Channel Fracturing Increases Effectiveness
Authors: Wilson Adam 
Published: February 2016

This article, written by Special Publications Editor Adam Wilson, contains highlights of paper IPTC 17409, “Channel Fracturing Enhanced by Unconventional Proppant Increases Effectiveness of Hydraulic Fracturing in Devonian Formations of Russia’s Oil Fields,” by Rifat Kayumov, SPE, Artem Klyubin, Andrey Konchenko, SPE, and Alexey Yudin, Schlumberger; and Alexander Khalzov, Vladislav Firsov, Evgeniy Nikulshin, Zdenko Kaluder, and Suleyman Sitdikov, SPE, Rosneft, prepared for the 2014 International Petroleum Technology Conference, Doha, Qatar, 20–22 January. The paper has not been peer reviewed.
Implementation of channel fracturing enhanced by rod-shaped proppant brings substantial value for depleted Devonian formations in the Orenburg region of Russia. Highly conductive channels inside the proppant pack significantly minimize the influence of multiphase and non-Darcy flow on overall production. The use of rod-shaped proppant in the final stage provides the highest possible conductivity in the critical near-wellbore region and eliminates the potential problem of proppant flowback.
Introduction
Fracturing is a standard completion method for all wells producing from Devonian formations in the Orenburg region of Russia’s Volga-Urals basin. Experience has shown that these fracturing treatments usually have some specific differences from fracturing in other parts of Russia. Low fracturing-fluid efficiency forces the use of large pad volumes and special fluid-loss additives. These actions decrease the risk of premature screenout but lead to significant reduction of fracture conductivity and effective fracture half-length, and, subsequently, result in a decrease in post-fracturing production. Even with large pad fluid volumes, almost all fracturing treatments in Devonian sandstone formations were finished in a tip-screenout regime when proppant starts to pack in the fracture during the treatment.
Just 5 years ago, proppant flowback was not observed frequently in Devonian formations. But, recently, the operating company noticed proppant- flowback problems becoming increasingly pronounced. The reason is reservoir- pressure depletion and severely increased multiphase flow inside the fractures.
To overcome the increasing negative effects of multiphase and non-Darcy flow on fracture conductivity, channel-fracturing technology was used. Although channel fracturing has already resulted in outstanding performance elsewhere, the technology was still new for conditions in the Volga-Urals Devonian formations (i.e., significant proppant packing is not typical for channel fracturing). Therefore, it was important to evaluate productivity through pilot wells stimulated with the new technique. For many treatments in the fracturing campaign described here, channel fracturing was enhanced by rod-shaped proppant to eliminate potential proppant-flowback problems and maximize conductivity of the near-wellbore region.
Hydraulic-Fracture Design: Optimization Under Uncertainty
Authors: Wilson Adam 
Published: February 2016

This article, written by Special Publications Editor Adam Wilson, contains highlights of paper OTC 25179, “Hydraulic-Fracture Design for the Lower Tertiary Gulf of Mexico: Optimization Under Uncertainty,” by S.B. Podhoretz, SPE, and P.P. Valko, SPE, Texas A&M University, prepared for the 2014 Offshore Technology Conference, Houston, 5–8 May. The paper has not been peer reviewed.
Massive hydraulic fracturing is a costly operation, particularly offshore where logistic constraints and high rig rates add significant financial risk. For the Lower Tertiary Gulf of Mexico, limited production from analogous fields and very high appraisal-drilling costs result in huge uncertainty for key reservoir parameters and a lack of consensus on best practices for fracture design. This paper provides new approaches to fracture design for thick, vertically anisotropic reservoirs, when considerable uncertainty in reservoir parameters amplifies the financial risks associated with water depth and remoteness.
Risk Analysis
Offshore applications are subject to significant risk because of hostile operating environments and the extreme costs involved. Although multistage hydraulic fracturing for productivity is common onshore, with financial risks well understood, the same cannot be said for offshore.
Compared with the entire cost of drilling and completing an offshore well, the proppant cost is nearly insignificant. However, the risk associated with fracturing is paramount because any nonproductive time could cost millions of dollars because of high day-rate costs.
For future analysis and forecasting, a Markov chain of completion time with respect to number of stages was generated. The Markov chain represents an independent transition from one state to the next. The transition does not depend on the previous states, only on the current state. Assuming a log-normal distribution, a series of Markov chains is generated to predict nonproductive time associated with fracturing additional stages.
These realizations are used to generate probability-density curves representing the time associated with fracturing more stages. The probability- density plots are given in Fig. 1.
These results can be used in determining the expected value and standard deviation of total (productive plus nonproductive) time associated with fracturing additional stages. Not surprisingly, increasing the number of stages moves the location of the peak to the right, but the spread of the curves grows even faster.
Application of Intelligent-Well Technology to an SAGD Producer: Firebag Field Trial
Authors: Carpenter Chris 
Published: February 2016

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 170153, “Application of Intelligent-Well Technology to an SAGD Producer: Firebag Field Trial,” by Richard M. Stahl and Jennifer D. Smith, Suncor Energy; Scott Hobbs, Halliburton; and Colin M. Clarke, Baker Hughes, prepared for the 2014 SPE Heavy Oil Conference—Canada, Calgary, 10–12 June. The paper has not been peer reviewed.
An even temperature conformance along the length of the horizontal well is key in maximizing steam-assisted- gravity-drainage (SAGD) production rates. When temperature logs are run in SAGD producers, temperature variations of greater than 50°C between the hottest and coldest spots are commonly observed. The authors theorize that this temperature distribution is related to an inflow distribution and that production rates could be improved if this temperature variance was narrowed.
Introduction
The Firebag project in northeastern Alberta uses SAGD to recover bitumen from the McMurray formation. SAGD uses stacked horizontal-well pairs, with the top well (injector) located 4 to 6 m above the bottom well (producer). Steam is injected into the top well, warming the bitumen and decreasing its viscosity to a point at which it will flow by gravity to the bottom well. The bottom well typically uses artificial lift to draw fluid into the wellbore and push it up to the surface facilities.
Firebag production wells are designed to promote even temperature conformance to maximize bitumen-production rates. The standard Firebag mechanical-lift design is shown in Fig. 1. Temperature conformance is measured by fiber-optic temperature logging while the production well is shut down for an electrical-submersible-pump (ESP) change.
A temperature survey was performed on a typical well, indicating that the coolest temperature (150°C) is located near the heel of the well (approximately 700 m) with a maximum value of 210°C near the midpoint of the well (approximately 1050 m). Field history at Firebag suggests that well conformance and bitumen-production rates could be improved through well design.
Epidemiological investigation and case–control study: a Legionnaires’ disease outbreak associated with cooling towers in Warstein, Germany, August–September 2013
Authors: Maisa Anna , Brockmann Ansgar , Renken Frank , Lück Christian , Pleischl Stefan , Exner Martin , Daniels-Haardt Inka , Jurke Annette 
Published: February 2016

Between 1 August and 6 September 2013, an outbreak of Legionnaires’ disease (LD) with 159 suspected cases occurred in Warstein, North Rhine-Westphalia, Germany. The outbreak consisted of 78 laboratory-confirmed cases of LD, including one fatality, with a case fatality rate of 1%. Legionella pneumophila, serogroup 1, subtype Knoxville, sequence type 345, was identified as the epidemic strain. A case–control study was conducted to identify possible sources of infection. In univariable analysis, cases were almost five times more likely to smoke than controls (odds ratio (OR): 4.81; 95% confidence interval (CI): 2.33–9.93; p < 0.0001). Furthermore, cases were twice as likely to live within a 3 km distance from one identified infection source as controls (OR: 2.14; 95% CI: 1.09–4.20; p < 0.027). This is the largest outbreak of LD in Germany to date. Due to a series of uncommon events, this outbreak was most likely caused by multiple sources involving industrial cooling towers. Quick epidemiological assessment, source tracing and shutting down of potential sources as well as rapid laboratory testing and early treatment are necessary to reduce morbidity and mortality. Maintenance of cooling towers must be carried out according to specification to prevent similar LD outbreaks in the future.
A FORMATION SCENARIO FOR THE DISK OF SATELLITES: ACCRETION OF SATELLITES DURING MERGERS
Authors: Smith Rory , Duc Pierre Alain , Bournaud Frederic , Yi Sukyoung K. 
Published: February 2016

ABSTRACT
The Disk of Satellites (DoS) observed in the Andromeda galaxy is a thin and extended group of satellites, nearly perpendicular to the disk plane, that share a common direction of rotation about the center of Andromeda. Although a DoS is also observed in the Milky Way galaxy, the prevalance of such structures in more distant galaxies remains controversial. Explanations for the formation of such DoSs vary widely from filamentary infall, or flattening due to the potential field from the large-scale structure, to galaxy interactions in a Mondian paradigm. Here we present an alternative scenario—during a merger, a galaxy may bring its own satellite population when merging with another galaxy. We demonstrate how, under the correct circumstances, during the coalescence of the two galaxies, the satellite population can be spread into an extended, flattened structure, with a common direction of rotation about the merger remnant. We investigate the key parameters of the interaction and the satellite population that are required to form a DoS in this scenario.
THE GLOBAL IMPLICATIONS OF THE HARD EXCESS. II. ANALYSIS OF THE LOCAL POPULATION OF RADIO-QUIET AGNs
Authors: Tatum M. M. , Turner T. J. , Miller L. , Reeves J. N. , DiLiello J. , Gofford J. , Patrick A. , Clayton M. 
Published: February 2016

ABSTRACT
Active galactic nuclei (AGNs) show evidence for reprocessing gas, outflowing from the accreting black hole. The combined effects of absorption and scattering from the circumnuclear material likely explain the “hard excess” of X-ray emission above 20 keV, compared with the extrapolation of spectra from lower X-ray energies. In a recent Suzaku study, we established that the ubiquitous hard excess in hard, X-ray-selected, radio-quiet type 1 AGNs is consistent with a reprocessing of the X-ray continuum in an ensemble of clouds, located tens to hundreds of gravitational radii from the nuclear black hole. Here we add hard X-ray-selected, type 2 AGNs to extend our original study and show that the gross X-ray spectral properties of the entire local population of radio-quiet AGNs may be described by a simple unified scheme. We find a broad, continuous distribution of spectral hardness ratio and Fe Kα equivalent width across all AGN types, which can be reproduced by varying the observer's sightline through a single, simple model cloud ensemble, provided that the radiative transfer through the model cloud distribution includes not only photoelectric absorption but also three-dimensional (3D) Compton scattering. Variation in other parameters of the cloud distribution, such as column density or ionization, should be expected between AGNs, but such variation is not required to explain the gross X-ray spectral properties.
ON THE NATURE OF X-RAY SURFACE BRIGHTNESS FLUCTUATIONS IN M87
Authors: Arévalo P. , Churazov E. , Zhuravleva I. , Forman W. R. , Jones C. 
Published: February 2016

ABSTRACT
X-ray images of galaxy clusters and gas-rich elliptical galaxies show a wealth of small-scale features that reflect fluctuations in density and/or temperature of the intracluster medium. In this paper we study these fluctuations in M87/Virgo to establish whether sound waves/shocks, bubbles, or uplifted cold gas dominate the structure. We exploit the strong dependence of the emissivity on density and temperature in different energy bands to distinguish between these processes. Using simulations we demonstrate that our analysis recovers the leading type of fluctuation even in the presence of projection effects and temperature gradients. We confirm the isobaric nature of cool filaments of gas entrained by buoyantly rising bubbles, extending to 7′ to the east and southwest, and the adiabatic nature of the weak shocks at 40″ and 3′ from the center. For features of ∼5–10 kpc, we show that the central 4′ × 4′ region is dominated by cool structures in pressure equilibrium with the ambient hotter gas while up to 30% of the variance in this region can be ascribed to adiabatic fluctuations. The remaining part of the central 14′ × 14′ region, excluding the arms and shocks described above, is dominated by apparently isothermal fluctuations (bubbles) with a possible admixture (at the level of ∼30%) of adiabatic (sound waves) and by isobaric structures. Larger features, of about 30 kpc, show a stronger contribution from isobaric fluctuations. The results broadly agree with a model based on feedback from an active galactic nucleus mediated by bubbles of relativistic plasma.
EFFECTS OF DYNAMICAL EVOLUTION OF GIANT PLANETS ON THE DELIVERY OF ATMOPHILE ELEMENTS DURING TERRESTRIAL PLANET FORMATION
Authors: Matsumura Soko , Brasser Ramon , Ida Shigeru 
Published: February 2016

ABSTRACT
Recent observations started revealing the compositions of protostellar disks and planets beyond the solar system. In this paper, we explore how the compositions of terrestrial planets are affected by the dynamical evolution of giant planets. We estimate the initial compositions of the building blocks of these rocky planets by using a simple condensation model, and numerically study the compositions of planets formed in a few different formation models of the solar system. We find that the abundances of refractory and moderately volatile elements are nearly independent of formation models, and that all the models could reproduce the abundances of these elements of the Earth. The abundances of atmophile elements, on the other hand, depend on the scattering rate of icy planetesimals into the inner disk, as well as the mixing rate of the inner planetesimal disk. For the classical formation model, neither of these mechanisms are efficient and the accretion of atmophile elements during the final assembly of terrestrial planets appears to be difficult. For the Grand Tack model, both of these mechanisms are efficient, which leads to a relatively uniform accretion of atmophile elements in the inner disk. It is also possible to have a “hybrid” scenario where the mixing is not very efficient but the scattering is efficient. The abundances of atmophile elements in this case increase with orbital radii. Such a scenario may occur in some of the extrasolar planetary systems, which are not accompanied by giant planets or those without strong perturbations from giants. We also confirm that the Grand Tack scenario leads to the distribution of asteroid analogues where rocky planetesimals tend to exist interior to icy ones, and show that their overall compositions are consistent with S-type and C-type chondrites, respectively.
AN HST SURVEY OF THE HIGHEST-VELOCITY EJECTA IN CASSIOPEIA A*
Authors: Fesen Robert A. , Milisavljevic Dan 
Published: February 2016

ABSTRACT
We present Hubble Space Telescope WFC3/IR images of the Cassiopeia A supernova remnant that survey its high-velocity, S-rich debris in the NE jet and SW counterjet regions through [S iii] λλ9069, 9531 and [S ii] λλ10,287–10,370 line emissions. We identify nearly 3400 sulfur emitting knots concentrated in ∼120° wide opposing streams, almost triple the number previously known. The vast majority of these ejecta knots lie at projected distances well out ahead of the remnant’s forward blast wave and main shell ejecta, extending to angular distance of

to the NE and

to the SW from the center of expansion. Such angular distances imply undecelerated ejecta knot transverse velocities of 15,600 and 12,700 km s−1, respectively, assuming an explosion date

AD and a distance of 3.4 kpc. Optical spectra of knots near the outermost tip of the NE ejecta stream show strong emission lines of S, Ca, and Ar. We estimate a total mass ∼0.1

and a kinetic energy of at least

erg for S-rich ejecta in the NE jet and SW counterjet. Although their broadness and kinetic energy argue against the Cas A SN being a jet-induced explosion, the jets are kinematically and chemically distinct from the rest of the remnant. This may reflect an origin in a jet-like mechanism that accelerated interior material from a Si-, S-, Ar-, and Ca-rich region near the progenitor’s core up through the mantle and H-, He-, N-, and O-rich outer layers with velocities that greatly exceeded that of the rapidly expanding photosphere.