bluuebunny/crossref_metadata_2025_split huggingface dataset:
Follow-up imaging to detect recurrence of surgically treated pediatric arteriovenous malformations
Authors: Lang Shih-Shan , Beslow Lauren A. , Bailey Robert L. , Vossough Arastoo , Ekstrom Joanna , Heuer Gregory G. , Storm Phillip B. 
Published: April 2012

Object
The true postoperative incidence of arteriovenous malformation (AVM) recurrence in the pediatric population remains largely unreported. Some literature suggests that delayed imaging studies should be obtained at 6 months to 1 year after negative findings on a postoperative angiogram. The aim of this study was to describe the timing of AVM recurrences after resection and the neuroimaging modalities on which the recurrences were detected.

Methods
This study was performed in a retrospective cohort of all pediatric patients treated surgically for AVM resection by a single neurosurgeon between 2005 and 2010. Patients were followed after resection with MR angiography (MRA) or conventional angiography, when possible, at various time points. A visual scale for compactness of the initial AVM nidus was used, and the score was correlated with probability of recurrence after surgery.

Results
A total of 28 patients (13 female, 15 male) underwent an AVM resection. In 18 patients (64.3%) an intraoperative angiogram was obtained. In 4 cases the intraoperative angiogram revealed residual AVM, and repeat resections were performed immediately. Recurrent AVMs were found in 4 children (14.3%) at 50, 51, 56, and 60 weeks after the initial resection. Recurrence risk was 0.08 per person-year. No patient with normal results on an angiogram obtained at 1 year developed a recurrence on either a 5-year angiogram or one obtained at 18 years of age. All patients with recurrence had a compactness score of 1 (diffuse AVM); a lower compactness score was associated with recurrence (p = 0.0003).

Conclusions
All recurrences in this cohort occurred less than 15 months from the initial resection. The authors recommend intraoperative angiography to help ensure complete resection at the time of the surgery. Follow-up vascular imaging is crucial for detecting recurrent AVMs, and conventional angiography is preferred because MRA can miss smaller AVMs. One-year follow-up imaging detected these recurrences, and no one who had negative results on an angiogram obtained at 1 year had a late recurrence. However, not all of the patients have been followed for 5 years or until 18 years of age, so longer follow-up is required for these patients. A lower compactness score predicted recurrent AVM in this cohort.
Micro Reactors, Flow Reactors and Continuous Flow Synthesis
Authors: Watts Paul , Wiles Charlotte 
Published: April 2012

Dr Paul Watts is a reader in organic chemistry at The University of Hull and since graduating from the University of Bristol, where he completed a PhD in bio-organic natural product synthesis, he has led the Micro Reactor Group at Hull. In this role, he has published 90 papers, and he regularly contributes to the field by way of invited book chapters, review articles, and keynote lecturers on the subject of micro reaction technology in organic synthesis. Dr Charlotte Wiles is the Chief Technology Officer at Chemtrix BV, and has been actively researching within the area of micro reaction technology for 10 years, starting with a PhD entitled Micro reactors in organic chemistry, which she obtained from The University of Hull in 2003. In the past decade, she has authored many scientific papers and review articles, recently co-authoring a book on the subject of micro reaction technology in organic synthesis. More recently, she has tailored her experience to the development and evaluation of commercially available continuous flow reactors, systems and peripheral equipment. This review article explains the advantages of micro reactors and flow reactors as tools for conducting organic synthesis and describes how the technology may be used in research and development as well as production. A selection of examples is taken from the literature to illustrate how micro reactors enables chemists to perform their reactions more efficiently than when using batch processes.
Approche interactionnelle et didactique invisible – Deux concepts pour la conception et la mise en œuvre de tâches sur le web social
Authors: Ollivier Christian 
Published: April 2012

Cet article commence par revenir sur ce qu'est la compétence d'action et de communication que nous concevons comme ayant lieu, toutes les deux, sous contrainte relationnelle. Sur cette base est proposée une approche interactionnelle de l'enseignement / apprentissage des langues qui ajoute aux catégories de tâches telles qu'elles sont généralement conçues (notamment par le CECRL) des tâches de la vie réelle à réaliser dans des interactions sociales réelles dépassant le cadre de la classe.Nous abordons ensuite le principe de didactique invisible qui a permis de construire les sites du projet Babelweb (Ollivier et al.) dans le but de créer des espaces d'interaction de type web social sur lesquels les apprenants peuvent se comporter en "acteurs sociaux" à part entière. La comparaison, croisée avec les résultats de recherches antérieures, du comportement langagier des apprenants sur un blogue de Babelweb et de francophones réalisant une tâche très similaire sur le web social permet de faire émerger les convergences et divergences entre le comportement de ces deux groupes et de faire ressortir les limites, mais aussi les avantages de la didactique invisible.
An Integrated Approach Towards Well Control of a HPHT Well
Authors: Shrivastav Piyush 
Published: April 2012

Abstract
Rising demand for energy has pushed the oil & gas exploration andproduction operations to harsher environments. High pressure and hightemperature (HPHT) is one of such challenging areas. HPHT developments presentchallenges at every stage. HPHT wells are defined as well having pressure above10,000 psi and temperature above 300°F. However the threshold is now pushing20,000 psi at 450°F. Many techniques that are applied to normal pressured wellmust be reexamined before its application in HPHT well else might result inconsiderable financial loss.
High pressure and high temperature impact mud properties in a dynamic way andcan have major effect on well control. This paper presents an integratedapproach on impact of high pressure and high temperature on mud rheology andthermo physical properties. It also discusses mechanism of thermaldisintegration of different types of mud i.e. bentonite mud, polymer mud andoil based mud, and measures to extend their temperature limits. This paper alsodiscusses various symptoms and remedial action to improve mud properties.
Preventing and controlling influxes of reservoir fluid into the well calledkicks are always central to drilling safety, but in HPHT wells the dangers froma kick are amplified. The three issues of HPHT drilling safety are kickprevention, kick detection and well control. This paper gives an overview aboutdetection of kick in a HPHT well, measures to prevent kick and well controlmeasures in case of a kick.

Introduction
The drilling of HPHT wells pose special challenges compared to standardwells:–High pressures and temperatures impact mud properties in a dynamic way, andcan have effects on well control–Increase in mechanical and fluid friction with well depth.–The majority of mud treatment chemicals derived from natural products beginto degrade at temperatures between250 and 275°F.–The volume of a HTHP gas kick remains virtually unchanged as it rises in theannulus from 14,000 to 10,000 ft [4265 to 3050 m]. From 10,000 to 2000 ft [610m] its volume triples. But from 2000 ft to the surface, there is a hundred-foldexpansion.–Put simply, a gas influx of 10 barrels at 14,000 psi becomes 4000 barrelsunder atmospheric conditions.–As reservoir fluid rapidly expands, it forces mud out of the well unloadingreducing mud in the well, cutting hydrostatic pressure at the formation, allowing additional reservoir fluids to enter, and ultimately causing ablowout.

Drilling Mud Composition
Drilling mud is a mixture of many components with different properties. Thevarious components react differently to pressure (p) and temperature (T). Thegas solubility and mixture properties of more complex hydrocarbon influxes varysignificantly. The most common components are base oil, water and weightmaterials (solids). Other components are chemically active, mix or dissolveinto the primary components of the mud for certain time periods during specificoperations on the well.
High-Resolution Seismic Imaging and Reservoir Characterization for Drilling Risk and Production Management
Authors: Yu Jen H. , Smith Mike 
Published: April 2012

Abstract
Often well planning, formation evaluation, reservoir engineering, andproduction management can ultimately be condensed to analyze and utilize thenature and spatial distribution of reservoirs and fluid properties. Thisobservation provides the motivation for this paper's objectives to:reviewthe impact of seismic resolution in imaging the reservoir, andexamine thechallenges and benefits of characterizing the reservoirs and fluid propertiesby integrating seismic, well, and engineering data at different measuringscales (resolutions) and sampling densities.
Two real case studies for sand andcarbonate reservoirs are used to illustrate how a new high resolution techniqueaffects seismic image and elevates reservoir characterization beyond thetraditional resolution enhancement methods.

Introduction
The use of resolution enhancement techniques to improve the seismic image hasbeen part of the seismic industry almost since the origin of seismic signalprocessing. Geophysicists have used statistical deconvolution, signaturedeconvolution, spectral whitening, log-bases blueing, and log-based waveletshaping to better improve the seismic resolution, image the subtle geologicalfeatures, and evaluate the prospects.
This paper begins with the theory of a novel resolution enhancement techniquein the continuous wavelet transform domain and its implementation methodology. Then it introduces a rigorous workflow to improve signal-to-noise ratio (SNR), velocity analysis, resolution, and anisotropic migration for better flattenedPSTM gathers, image, and prestack inversion. Finally, presents real casestudies for conventional and unconventional play types to illustrate how highresolution (HR) in seismic imaging and inversion improves the subsurface imagefor detailed stratigraphical and structural interrelation, reservoircharacterization, and production management. The two case studies are:complex Yegua sands with various thickness and spatial distribution fromlowstand deltas and slope fans in a shelf margin environment, andlowporosity Edward carbonate reservoirs from distal slope wackestones, reef andbank complexes, and back reef lagoonal deposits in a progradational sequence.
Both studies are presented to show the holistic workflow of prestack dataprocessing, resolution enhancement, petrophysical evaluation, and prestackinversion.

Theory: High Resolution Enhancement with Bandwidth Extension
The bandwidth extension technique described here attempts to recover the lostwavelet characteristics from the available bandwidth in seismic data. Theavailable bandwidth acts as the fundamental frequencies, for which harmonicsand subharmonics are computed from and compared with the data, and then addedback to the wavelet by a convolutional-like process in the CWT domain. Thiseffectively reshapes the wavelet and broadens the seismic bandwidth. Any highharmonic and low subharmonics frequencies that do not match reflectivity in therecorded seismic data will not remain in the final result (Smith et al.,2008).
The Benchmarking of the new ISO for the Site Specific Assessment of Mobile Jack-Up Units
Authors: Stiff John James , Lewis David Roger 
Published: April 2012

Abstract
The paper presents the logic behind, and the results of, a series of comparisonanalyses between a number of jack-up site-specific assessments using both thenew ISO 19905-1 on the site-specific assessment of mobile jack-up units [Ref.1] and the Society of Naval Architects and Marine Engineers Technical &Research Bulletin 5-5A [Ref. 2]. The study shows that the differences in theresults of analyses between those undertaken using 5-5A and ISO 19905-1 aregenerally small, although one area of potentially larger difference, which wasintentionally excluded from the comparison, (the normally lower kinematicsreduction factor in 19905) could lead to lower wave loads in 19905calculations.
ISO 19905 is largely based on 5-5A, however, the ISO development incorporatedsome major changes, including:Enhancements to calculation methodsSignificant changes in the geotechnical calculations, including the method ofcalculating acceptable bearing capacity, incorporation of deep penetrationcases, distinction between backfill and backflow, etc.Changes to enhance compatibility with other ISO documents in the 19900series, particularly ISO 19902 addressing Fixed Offshore Structures [Ref. 3](e.g. the structural code checks for tubular members)Introduction of additional structural member checksRe-structuring of 5-5A into a more logical ISO formatIntroduction of "benign" changes required for ISO compatibility (e.g.introduction of apparent and intrinsic wave periods), although some proved tobe less benign than othersAdditional loadcases for jack-ups operating close to resonance
Given so many changes, there was concern that the ISO may not be useable (e.g.there would be gaps, inconsistencies, and serious transposition errors), andeven if an analysis could be undertaken using it, the analysis results would besignificantly different from a similar assessment using 5-5A.
To ensure the compatibility and acceptability of ISO assessments results, a twopart benchmarking process was undertaken:
Part 1 Contract a single consultant to ensure the complete ISO could be used toproduce an answer. In effect, could an analysts start an analysis using thedocument and arrive at a solution - regardless of whether the solution wascorrect. This work resulted in some important changes.
Part 2 Contract four consultants to assess four jack-up designs, and comparethe results to a comparable series of assessments based on SNAME Bulletin 5-5A. In most cases each jack-up was assessed by two consultants with the analysesaligned at specific points. Alignment allowed differences in ISO interpretationto be identified, and ensured that results did not diverge as they progressed.A detailed sample calculation "Go-By" was also produced.
Production Optimization by Solving the Well Location Problem
Authors: Santana Roberta 
Published: April 2012

Abstract
The paper presents a process for determining optimal subsurface producing wellsand production unit location in a field to improve reservoir performance, recovery and reduce the pipeline total length used, decreasing costs, maximizing the revenue. The process is illustrated by optimizing well locationsusing statistics analysis, after several static reservoir model simulations, under defined parameters. These locations are then optimized with dynamic flowsimulation values' Sensibility Analysis. The response surface methodology isapplied to understand the flow distributing along the pipelines and thendetermine the best production unit location. This method is demonstrated byapplying it to a field scale simulation model considering only producingwells.

1. Introduction
The reservoir simulation is related to the development and management of an oilfield in order to establish a field fluid behavior model, previewing the oilrecovery. It provides enough data to analyze if the project matches theeconomic and safety prospection. During the development of the field, thereservoir simulation model is used as a decision tool to select the bestdevelopment project and also provide for the production of oil, gas and waterfield. Simulators are used in order to receive the characteristics of the rock, fluid and location of the field as well as its faults, creating a realthree-dimensional model of the subsurface reservoir. The location of wells inthe reservoir to be explored is one of the challenging steps in the process ofdecision the best strategy for developing a field that includes severalparameters, such as uncertainties and geological properties of confinedfluids.
Optimum well placement is a crucial step in a field development. The distancesbetween wells and platform are related to their productivity: short distancesperform less pressure drop along pipelines leading to higher production. Thenecessity to obtain maximum recovery with minimum investments can be addressedby reducing the cost of the installations as pipelines and equipments. Thus, the cost of the facilities necessary to maintain a satisfactory production of afield cannot bring enough profit and that field is not economically attractiveand viable. The structure optimization in the allocation of productionfacilities should also consider the economic variables associated[2] with theunderstanding that the scenario that produces more may not be the mostinteresting for the company.
SS MTS: Subsea Monitoring - High Resolution 3D Laser Imaging for Inspection, Maintenance, Repair, and Operations
Authors: Embry Carl , Hardy Mark , Nickerson Brett , Manning Neil , Goodyear Damien , Richardson Donald , Pappas James Marcus 
Published: April 2012

Abstract
In January 2011, 3D at Depth was awarded a RPSEA contract to bringhigh-resolution three-dimensional (3D) laser imaging technology from the labinto an underwater environment for the oil and gas industry. During theproject, CDL Inc. provided expert engineering support and materials to marinizethe system. The project included two underwater trials which demonstrated thefeasibility of utilizing high resolution laser detection and ranging (LADAR) ina subsea environment.
3D laser imaging is a powerful data collection system that provides 3-Dinformation for a specific area of interest. It is the predominate technologyfor terrestrial survey, construction, as-built analysis, and large-scaleretro-fits. The 3D laser imaging market is a mature multi-billion dollarindustry with an eco-system of software, expertise, and best practices. Developing the technology to provide high-definition subsea laser imagingenables the deep water industry to use the current state of the art in 3Dmetrology and related best practices developed for the terrestrialmarket.
This paper discusses some of the theory behind subsea laser imaging andcompares this theory to the first set of underwater tests in a pool. Terrestrial laser scanners commonly produce centimeter spatial and rangeaccuracy at several hundred meter range. Due to the absorption of water, realizable deepwater systems are limited to tens of meters range depending onthe target and water conditions. To our knowledge, this is the first timesub-centimeter accuracy at greater than 6m range is demonstrated for anunderwater laser system.
This technology is essential for better management of deep water assets. Thelack of timely and accurate survey-quality 3D measurements poses an integritymanagement challenge for such assets. A lack of accurate data results in eitherhigher risks or higher costs to build and maintain environmentally safeproduction and product transportation systems. The speed and precision of thetechnology developed by this project reduces operating costs for underwaterinspection, maintenance, and repair; reduces environmental risk through moreaccurate inspection; significantly improves construction practices and quality/ reliability; reduces risks to high value assets; and provides rapid access tosharable survey-quality as-built data before, during and afterconstruction.
New Research and Application of High Efficient Development Technology for Offshore Heavy Oil in China
Authors: Liu Dong , Zhao Chunming , Su Yanchun , Li Yunpeng , Zhang Fengyi , Huang Yinghui 
Published: April 2012

Abstract
China Offshore oilfield is rich in heavy oil, M oilfield in Bohai Bay is themost thick heavy oil field in offshore by far with the formation oil viscosityas high as 450 ~ 950mPa.s. Using conventional oil field development (depletionand water flooding), the heavy oil field exposed its limits, such as lowproductivity of single well, low production rate and low predictedrecovery.
As we all know, the development effect of thermal recovery is not only relatedwith the thermal recovery methods (steam stimulation, steam flooding, etc.), but also related with the thermal medium (steam, hot water, flue gas etc.). Anew thermal media called multi-thermal fluid, which contains steam, hot waterand flue gas was researched for horizontal well stimulation, which is to injectN2 and CO2 at the same time when injecting steam. This multi-thermal fluidcould employ various mechanisms of each fluid, including reducing oil viscosityby heating and dissolving gas, increasing pressure by injecting gas, expandingheating range, reducing heat loss and gas assisting gravity drive etc. With theadvantages of single thermal injection, this method made up the disadvantagesof single thermal fluid injection and can improve steam stimulation effect insome special formation conditions.
In this article, the author first analyzed the characterization ofmulti-thermal fluid, and then researched its stimulation theory. Based on thistheory, the single element of geological data, such as dip angle, permeability, rock compression coefficient, formation thickness, oil viscosity, and injectiondata, such as injection volume, gas-water-ratio and CO2 concentration wasanalyzed using numerical simulation software. Based on this result, selectingdata that make more contribution in incremental oil, production rate, and EORto make sensitivity study to summarize formation that multi-thermal fluid couldbe applied.
Dynamic Response of the Baldpate Compliant Tower Platform to Major Hurricanes in Gulf of Mexico
Authors: Chang Ben C. , Peng Bor-Feng , Edel James Craig , Kallaby Joe 
Published: April 2012

Abstract
The first free-standing compliant tower structure, Hess Corporation's"Baldpate" platform in Garden Banks Block 260 in the Gulf of Mexico, wasinstalled in a water depth of 1,648 ft in 1998. After its installation, Hessinstalled accelerometers at the upper deck level. Since then, four majorhurricanes have occurred in the Gulf of Mexico: Ivan (2004), Katrina (2005), Rita (2005), and Ike (2008).
The platform has been analyzed using hindcasts for several of these storms. Thework for Rita is complete and of some interest, and so it is presented in thispaper. Rita was one of the most intense Atlantic hurricanes ever observed inGulf of Mexico, and its track passed just west of GB260. This paper compares, and shows good correlation between measured and predicted structural responsesfor Rita. In addition, the paper presents analysis results in terms of AISCstress ratios and pile-load safety factors.
Also presented is a comparison between: the original design storm criteria;newly-generated 100-year criteria based on the GOMOS08 database (which includeshindcasts of all the storms mentioned above); and API RP 2INT-MET West CentralRegion design guidelines.

Introduction
The first part of this paper presents measured responses from Rita, Katrina, Ivan and Ike. These are followed by a presentation of the results of astructural analysis [1][2], via time-domain simulation, of the platform using ahindcast of Rita conditions at the site.
For orientation, Figure 1 is a plot of the platform structural model, alongwith the coordinate system. Figure 2 shows a plan of the base of the platformand the skirt-pile system.
An Overview of Baldpate Compliant Tower Platform Project can be found inReference [3].