bluuebunny/crossref_metadata_2025_split huggingface dataset:
Controlled Pressure Drilling and Downhole Isolation Valve Technologies for Enhancing Coal Seam Gas Drilling and Completion Operations in Australia
Authors: McHardy Mark Lawrence , Wuest Chad Henry , Toralde Julmar Shaun 
Published: September 2014

Abstract
The use of controlled pressure drilling (CPD) techniques in tandem with downhole isolation valve (DIV) technologies to improve drilling and completion operations for coal seam gas (CSG) in Australia has yet to be maximized, especially for wells that are drilled into dewatered coal formations where reservoir pressures are below sub-hydrostatic levels and cannot be drilled conventionally as circulation losses would result.
Advancements in rotating control devices (RCD) and CPD technologies where backpressure is exerted on the annulus of the well during drilling in order to control the bottomhole pressure while drilling with air, mist or foam fluid systems have increased their potential to enhance the drilling process. The utilization of a DIV to keep the well underbalanced during tripping and when the completion assembly is ran minimizes the pressure spikes that the inherently unstable coal formation sees and helps ensure that the completion is ran to the ideal depth and maximum production is realized. Together, CPD and DIV solutions can improve the economics of CSG wells in Australia. Case studies of previous deployments involving a tandem application of these technologies and their impact will also be discussed.
A Probabilistic Approach to Predicting Coalbed Methane Well Performance Using Multi-Seam Well Test Data
Authors: Burgoyne M. W. , Clements G. M. 
Published: September 2014

Abstract
Significant heterogeneity in production rates from coalbed methane (CBM) wells is observed throughout the Surat and Bowen Basins in Eastern Queensland, Australia. Typically, individual well performance predictions are conducted using deterministic coal properties obtained from core data in combination with permeability and pressure measurements from multi-seam well testing. Due to the heterogeneous nature of the coal, the total permeability measured across the tested interval in a single well will likely not represent the behaviour of even the closest of neighbouring wells. This leads to challenges in mapping permeability between and away from wells, and producing representative predictions for field development.
A new method is proposed to take a statistically significant population of multi-seam CBM permeability test results, correct to equivalent expected single seam test results and, using the full dataset, relate those results to a probabilistic single well performance envelope for a defined area with similar geological properties and setting. Depth, gas content, saturation, total net coal isopachs and any unique structural features are the primary control points for defining these ‘geodomains’.
The resultant single well performance envelopes remove the need to subjectively choose an average permeability to use for each well or coal measure. The results have been demonstrated to reasonably represent the range of observed actual peak water and gas productivities across a variety of geological areas in the Surat and Bowen basins.
This provides a method by which discrete representations of well families can be made for a particular geologic setting; leading to an understanding of the range of potential well outcomes which cannot be achieved using a typical deterministic approach.
Studies on ASP Flooding Formulations Based on Alkylbenzene Sulfonate Surfactants
Authors: Zhu Youyi , Cao Fengying , Bai Ziwu , Wang Zhe , Wang Hongzhuang , Zhao Shumei 
Published: September 2014

Abstract
Alkali-surfactant-polymer (ASP) flooding field tests showed a significantly enhanced oil recovery in Chinese mature oilfields. However, there were still some limitations remained in ASP flooding technique, including scaling, corrosion and emulsification bring problems in lifting system, and produced liquid hard to treatment in strong caustic ASP system (using sodium hydroxide with high concentration for example). In order to avoid the side effects caused by strong alkali, development of chemical combination flooding system with low damage formulations is being a hot topic in application of ASP flooding technique.
In this research, the preparation, interfacial tension (IFT) properties and oil displacement experiments of synthesized alkylbenzene sulfonate surfactants were mainly studied in weak alkaline ASP flooding, in order to better understand the relationship between IFT performance and surfactant structure at different types of alkali condition, and to optimize low damage formulations in ASP Flooding.
A series of alkylbenzene sulfonate surfactants were synthesized. The IFT measurements of both model oil/water and crude oil/formation water indicated that the molecular structure of surfactants such as length of carbon chains could remarkably affect the IFT. Low damage formulation of ASP system was selected for Daqing crude oil and formation water, based on adjusting both of molecular weight and structures of alkylbenzene sulfonate surfactant. The ultralow IFT between crude oil and ASP displacing liquid was obtained at the concentration range of surfactants from 0.05wt% to 0.3wt% and Na2CO3 or Na2CO3+NaHCO3 (1:1) from 0.4wt% to 1.0wt%. The pH value of the chemical systems was lower than that of NaOH system. Core flooding experiments showed that the incremental oil recovery by weak alkaline ASP flooding formulations could reach 22-23% over water flooding.
Development of chemical flooding with low damage formulations is very important and might facilitate the further applications of ASP chemical combination flooding in the different types of reservoirs.
Field Pilot of Gel Barriers Placement for In-depth Fluid Diversion in Daqing Oil Field
Authors: Lv Jing , Li Junjian , Liu Yuzhang , Xiong Chunming , Li Yikun , Wei Falin 
Published: September 2014

Abstract
Due to severe heterogeneity of thick positive rhythm reservoir and the gravity influence, the injected water channels and ineffectively cycles in high-permeability layers at the bottom of thick reservoir. An innovative in-depth fluid diversion technique, gel barrier placement, will be a promising approach to tap the potential of remaining oil in positive rhythm reservoirs in the period of high water-cut, which involves injecting gel into the radial laterals in the vertical wells between the injectors and producers to form ‘gel barriers’, then follow-up injected water will bypass these barriers and be diverted into the upper low permeability zones where the remaining oil is relatively enriched. As a result, the sweep efficiency of the upper low-permeability zones can be increased. A pilot of gel barrier placement was conducted in Daqing oil field. The paper deals with well pattern and chemical agents’ selection, injection scheme design, numerical simulation, and field implementation results.
Research on Pipe-in-Pipe Coiled Tubing
Authors: Chen Yingchun , Zhang Shimin , Xu Kebin , Wang Wenming , Xiong Minghao 
Published: September 2014

Abstract
Under balanced technology is now urgently needed to handle weak and leakage conditions. This paper describes a new Pipe-in-Pipe Coiled Tubing which can form its own circulation passage. Due to its unique property, Pipe-in-Pipe Coiled Tubing is especially suitable for low-washed sand, plugging, drilling and grinding, drilling and other operations. Current applications of Pipe-in-Pipe Coiled Tubing is overviewed in this paper; an indoor bench is also built to experimentally study the axial force transfer behavior of Pipe-in-Pipe Coiled Tubing, results shows: due to the difference on Moment of inertia, Pipe-in-Pipe Coiled Tubing's axial force transfer efficiency would be higher than that of Traditional Coiled tubing under the same condition. This paper would be useful for the practical application of Pipe-in-Pipe Coiled Tubing.
Water Control Success in Onshore and Offshore Horizontal Wells Completed with Slotted Liners by Annular Isolation - Case Studies from China
Authors: Wei F. , Liu Y. , Xiong C. , Liu H. , Li Y. , Xu H. , Chen R. , Li L. 
Published: September 2014

Abstract
This paper describes the applications of annular chemical packer (ACP) with highly tailored thixotropic characteristics in horizontal wells completed with slotted liners. The purpose of the applications was to provide a cost effective annular isolation method for water control in horizontal sections.
The rheological properties of ACP, the placement techniques of ACP, the subsequent treatment procedures, and the uncertainties involved were provided.
The oil rate of the candidate onshore horizontal well M28-P7 was only 0.5m3/d, with 99% water cut. Production logging identified that about 86% of liquid rate was produced from the toe section. The ACP was placed across the shale between the two different liquid-producing zones, and a mechanical plug was dropped at middle of the ACP site. Then effective acidizing was performed for the heel section in order to gain higher permeability. After the treatments, the water cut decreased to 83% while the corresponding oil gain reached up to 5.3m3/d, 20 times that of the pre-treatment scenario.
The other similar treatment was performed in offshore horizontal well A2h after production logging. Two ACP plugs were designed and an optimized recompletion string was put into the well. The water control operation went smoothly, which significantly decreased the water cut to 3% from 74% and the oil rate was increased to 187m3/d, with the net oil increased by about 100m3/d over the pre-treatment scenario. This is the first ever successful water control operation with water diagnosis in an offshore well with a tough completion in the South China Sea.
Case histories indicate that using ACPs was the right choice for blocking water in the sand screen liner completion with high level technical success and economic feasibility. Also a comprehensive and detailed water control design based on production logging results, completion, and reservoir permeability distribution is the key for successful water shutoff.
Petrophysical Evaluation of Deep Sandstone Gas-Bearing Reservoirs Using LWD Time-Independent Logs Paradigm
Authors: Fakolujo Kehinde M. , Al-Belowi Ali , Gzara Kais , Onuigbo Oluchukwu L. 
Published: September 2014

Abstract
Formation evaluation can become complex when the invading mud-filtrate properties are unusual, variable or unknown like in sodium potassium (Na/K) formate water base mud (WBM) environments. In these situations, computed reservoir properties are adversely affected and become strongly dependent on the formation invasion status.
The Permian age reservoir discussed in this paper, consists of highly unconsolidated heterogeneous sandstone sequences, saturated with condensate rich gas. From a drilling engineering perspective, the shales are often unstable, requiring high mud overbalance to maintain hole stability in wells with high inclinations, which resulted in recurrent differential sticking incidents. The use of formate based drilling fluids in this field, gained acceptance over time, primarily to minimize drilling problems.
The downside of formate muds, however, is that log data interpretation encounters serious challenges because of the uncertain petrophysical properties of the mud, affecting log measurements in two ways. The first are those effects related to the mud present inside the borehole and surrounding the tool, or so-called environmental effects. The second are those related to the invading mud-filtrate present inside the formation, resulting in pessimistic porosity, mineralogy and permeability estimates.
This paper shows how Na/K formate WBM filtrate effects can be identified and eliminated using Logging-While-Drilling (LWD) time-lapse data acquisition and analysis to provide time-independent logs in a manner that renders the logs immune to various mud-filtrate effects. These logs, together with a corresponding new petrophysical model, make it possible to do away with the mud-filtrate petrophysical properties, and to solve for porosity, mineralogy and fluid saturations from standalone nuclear measurements, irrespective of the formation invasion status.
Moreover, the results demonstrate how valuable LWD time-lapse data acquisition can be, and that data acquired while drilling – especially resistivity data in this instance – are important to validate this novel formation evaluation interpretation approach.
A Laboratory and Numerical Simulation Study of Co-optimizing CO2 Storage and CO2 EOR
Authors: Kamali Fatemeh , Hussain Furqan , Cinar Yildiray 
Published: September 2014

Abstract
This paper presents experimental observations that delineate co-optimization of CO2 EOR and storage. Pure supercritical CO2 was injected into a homogeneous, outcrop sandstone under various miscibility conditions. A mixture of hexane and decane was used for the oil phase. Three experiments were run at 70°C and different pressures (1,300, 1,700 and 2,100 psi). Each pressure was determined using a PVT simulator to create immiscible, near-miscible and miscible displacements. Oil recovery, differential pressure and compositions were recorded during experiments. A co-optimization function for CO2 storage and incremental oil was defined and calculated using the measured data for each experiment. A compositional simulator was then used to examine gravity effects on displacements and derive relative permeabilities.
Experimental observations demonstrate that an almost similar oil recovery was achieved during miscible and near-miscible displacements whereas about 18% less recovery was recorded in the immiscible displacement. More decane was recovered in the miscible and near-miscible displacements than the immiscible displacement. The co-optimization function suggests that the CO2 storage efficiency was highest in the near-miscible displacement and that the near-miscible displacement displayed the best performance for coupling CO2 EOR and storage. Numerical simulations show that, even on the laboratory scale, there were significant gravity effects in the near-miscible and miscible displacements. It was revealed that the near-miscible and miscible recoveries depend strongly on the end-point CO2 relative permeability which increased with miscibility.
High-performance simulation-based algorithms for an alpine ski racer’s trajectory optimization in heterogeneous computer systems
Authors: Dębski Roman 
Published: September 2014

Abstract
Effective, simulation-based trajectory optimization algorithms adapted to heterogeneous computers are studied with reference to the problem taken from alpine ski racing (the presented solution is probably the most general one published so far). The key idea behind these algorithms is to use a grid-based discretization scheme to transform the continuous optimization problem into a search problem over a specially constructed finite graph, and then to apply dynamic programming to find an approximation of the global solution. In the analyzed example it is the minimum-time ski line, represented as a piecewise-linear function (a method of elimination of unfeasible solutions is proposed). Serial and parallel versions of the basic optimization algorithm are presented in detail (pseudo-code, time and memory complexity). Possible extensions of the basic algorithm are also described. The implementation of these algorithms is based on OpenCL. The included experimental results show that contemporary heterogeneous computers can be treated as μ-HPC platforms-they offer high performance (the best speedup was equal to 128) while remaining energy and cost efficient (which is crucial in embedded systems, e.g., trajectory planners of autonomous robots). The presented algorithms can be applied to many trajectory optimization problems, including those having a black-box represented performance measure
Conceptual Modeling of Drag-Augmented Supersonic Retropropulsion for Mars Entry, Descent, and Landing
Authors: Skeen Michael A. , Starkey Ryan P. 
Published: September 2014

The development of new decelerator technologies will be required as the payload mass for future Mars landing missions increases beyond the current state-of-the-art capability. This study examines the potential for supersonic retropropulsion applied on entry, descent, and landing vehicles to increase the landed payload mass. This study describes the development of a model characterizing the drag augmentation capabilities of peripheral-nozzle supersonic retropropulsion flow interactions. The model captures the dominant flow physics of pressure conservation through shock cascade structures and predicts an increase in the drag coefficient over the nominal drag coefficient of a 70 deg sphere-cone aeroshell by 14% at high Mach numbers. This study also describes drag-augmented supersonic retropropulsion operation concepts for use in Mars entry, descent, and landing. Drag-augmented supersonic retropropulsion is found to be most effective when used in the region of maximum freestream dynamic pressure. The vehicle dry mass is increased by 47% over the reference ballistic trajectory. The region of influence for aerodynamic–propulsive interactions is identified for a set of constant-thrust supersonic retropropulsion trajectories. A hybrid concept combining supersonic retropropulsion and an inflatable aerodynamic decelerator is found to be capable of providing vehicle dry masses that are 707% larger than the baseline vehicle studied.
Gamma Knife rhizotomy-induced histopathology in multiple sclerosis–related trigeminal neuralgia
Authors: Phillips David B. , Del Bigio Marc R. , Kaufmann Anthony M. 
Published: September 2014

Object
In this report, the authors describe the pathological changes in the human trigeminal nerve after Gamma Knife radiosurgery.

Methods
Three trigeminal nerves of patients with multiple sclerosis (MS)–related trigeminal neuralgia (MSTN) after Gamma Knife radiosurgery and other ablative procedures were examined by a neuropathologist. These cases were compared with 3 patients with typical TN who underwent partial surgical rhizotomy following recurrent symptoms after gasserian injury procedures, as well as with autopsy specimens from patients with and without MSTN.

Results
The three irradiated MS-TN specimens exhibited axon loss, demyelination, myelin debris, and fibrosis. Mild lymphocytic infiltrate was present in all 3 samples from MS-TN patients. The nonirradiated trigeminal nerve samples were generally well myelinated with rare degenerating axons. The microscopic findings in trigeminal nerve autopsy specimens were normal in patients without TN, with MS but not TN, and MS-TN.

Conclusions
The inflammation observed in MS-TN specimens collected following Gamma Knife radiosurgery has not previously been described in the literature. These data provide new insight into the changes that occur in trigeminal nerve following stereotactic radiosurgery.
The role of spinal fusion in the treatment of cervical synovial cysts: a series of 17 cases and meta-analysis
Authors: Bydon Mohamad , Lin Joseph A. , de la Garza-Ramos Rafael , Sciubba Daniel M. , Wolinsky Jean Paul , Witham Timothy F. , Gokaslan Ziya L. , Bydon Ali 
Published: September 2014

Object
This study was undertaken to compare surgical outcomes between patients with atlantoaxial versus subaxial cervical synovial cysts (CSCs) and to compare outcomes between patients who underwent decompression alone versus decompression and fusion for the treatment of CSCs.

Methods
The authors present a series of 17 cases involving patients treated at their institution and report the surgical outcomes. Due to the rarity of CSCs, a meta-analysis was conducted, and results of the literature search were combined with the case series to enhance the power of the study.

Results
Seventeen patients underwent surgical treatment for CSCs at our institution: 3 patients (17.6%) had atlantoaxial cysts and 14 (82.3%) had subaxial cysts. Of the 17 patients, 16 underwent a decompression and fusion; most patients experienced symptom resolution at last follow-up, and there were no cyst recurrences. A total of 54 articles (including the current series) and 101 patients were included in the meta-analysis. The mean age at presentation was 64 ± 13.9 years, and the most common symptoms were motor and sensory deficits. Forty-one patients (40.6%) presented with atlantoaxial cysts, and 60 (59.4%) with subaxial cysts. There were no significant differences between groups in terms of presenting symptoms, Nurick scores, surgical treatment, or surgical outcomes. Fifty-two patients (51.4%) underwent surgical decompression without fusion, while 49 patients (48.6%) underwent fusion. The preoperative Nurick scores were significantly lower in the fused group (p = 0.001), with an average score of 1.32 compared with 2.75 in the nonfused group. After a mean follow-up of 16.5 months, a difference of means analysis between final and preoperative Nurick scores revealed that patients who received a decompression alone improved on average 1.66 points (95% CI 1.03–2.29) compared with 0.8 points (95% CI 0.23–1.39) in the fused group (p = 0.004). However, there was no statistically significant difference in symptom resolution between the groups, and the rate of cyst recurrence was found to be 0%.

Conclusions
In this study, patients with CSCs had similar outcomes regardless of cyst location and regardless of whether they underwent decompression only or fusion. In the authors' institutional experience, 16 of 17 patients underwent fusion due to underlying spinal instability. While there were no reports of cyst recurrence in their series or in the literature in patients who only received decompression, this is likely due to the limited follow-up time available for the study population. Longer follow-up and prospective and biomechanical studies are needed to corroborate these findings.
Avec sa jambe de boiteuse. Lecture ethnocritique d' À une passante de Baudelaire
Authors: Ménard Sophie 
Published: September 2014

Cette lecture ethnocritique d’« À une passante » de Baudelaire vise à prendre en compte la culture du poème en réinscrivant cette passante dans une dynamique anthropologique du passage (celui du « grand deuil ») et en établissant une équivalence symbolique entre la « jambe de statue » et la boiterie. Alliant une poétique du texte et une ethnologie du symbolique, cet article fait l’hypothèse générale que le poème obéit à des réglages culturels bien particuliers, qui mettent l’accent sur des logiques de la traversée rituelle et de la mobilité entravée.
Passé, présent et futur de l'anthropologie littéraire en Italie
Authors: Scafoglio Domenico , Lamb Mary 
Published: September 2014

L’article aborde les relations entre anthropologie et littérature en Italie. Il montre d’abord comment l’intérêt pour la littérature « cultivée » a remplacé progressivement celui pour la littérature « populaire ». Le livre The Broken Fountain de Thomas Belmonte et les travaux menés à l’université de Salerne ont contribué ensuite à renouveler les débats du côté des anthropologues. De leur côté, les spécialistes italiens de la littérature, influencés notamment par les travaux de Bakhtine, ont aussi intégré certaines réflexions des anthropologues.
Des enfants, des fous, des chiens. Des jeux brutaux et sérieux dans les mornes haïtiens
Authors: Mézié Nadège 
Published: September 2014

Dans les mornes haïtiens, par intermittence, de manière disruptive, et rarement prémédités, deux événements collectifs donnent à voir des accès de violence perpétrés principalement par des enfants : l’explosion agressive des enfants à l’égard de personnes considérées comme folles et la chasse aux chiens prédateurs de bétail. Dans les deux cas, l’exécution d’actions violentes est accompagnée d’une exultation collective et d’une émulation compétitive témoignant du caractère ludique de ces deux moments intenses de la vie sociale enfantine. Ces deux événements collectifs sont à inscrire dans le répertoire varié et riche des manifestations violentes à Haïti lors desquels les enfants font l’apprentissage de manières d’être et de faire violentes valorisées par le groupe.