bluuebunny/crossref_metadata_2025_split huggingface dataset:
Absolute Multiphase Electrical Capacitance Tomography Reconstruction Using a Level Set Algorithm
Authors: Alhosani Esra , Soleimani Manuchehr 
Published: November 2016

Abstract
Multiphase flow measurement is a vital topic in the process industries especially the oil and gas industry due to the critical need of measuring the individual phases of any multiphase process. One new method for multiphase flow measurement is the use of process tomography, however, multiphase flow imaging is a challenging topic in industrial process tomography that is still in the stage of research. In this article, simulation and experimental results of reconstructing the permittivity profile of multi-phase material from absolute Electrical Capacitance Tomography (ECT) data are presented. A multiphase narrowband level set algorithm is developed to reconstruct the interfaces between three or four phase permittivity values. The level set algorithm is capable of performing absolute value ECT reconstruction, which is to image multiphase permittivity by using only one set of ECT measurement data. The algorithm is tested with high contrast and low contrast multiphase data, which adds more to the challenge. Simulation and experimental results shows the superiority of this algorithm over classical pixel based image reconstruction methods. Absolute multiphase ECT reconstruction using a level set algorithm is presented and critically evaluated for the first time in this study which was first published in the Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2016.
Systematic Field Validation of New Casing Wear Quantification Process
Authors: Aichinger F. , Dao N. H. , Brillaud L. , Nobbs B. , Delapierre A. , Pinault C. , Rossi X. 
Published: November 2016

Abstract
Casing wear predictions are necessary for a fit-for-purpose, cost efficient casing design. In order to achieve a reliable casing wear prediction from simulations, three objectives have to be met: (1) Accurate modelling of mechanical work, (2) accurate derivation of casing wear from mechanical work and (3) accurate wear factor calibration through MFCL (Multi Finger Caliper Log) interpretation. The paper presents a theoretical description of all three steps and their application on a representative field case, highlighting recent improvements and reducing uncertainties at each step with a focus on a newly developed MFCL interpretation methodology.
To accurately derive the mechanical work an advanced stiff-string model(3) is used to simulate the history of side forces for each rotating operation, of each BHA, which was in contact with the casing. Accurate surveys and small calculation increments are vital. Operation parameters must be data mined with great care.
To properly derive the wear from simulated mechanical work, a 3-D oriented wear model is used. This 3D mesh is able to distinguish the influence of different contact geometries on the wear groove shape and the location of thinnest wall thickness. Due to the usage of an advanced stiff-string model, drillstring body contact points are identified and therefore the wear model allows the input of different wear factors for different types of contacts (Tooljoint, Pipebody, Torque reducer)(12). Additionally, the model allows the application of linear and non-linear wear models.
To properly calibrate wear factors, a reliable and robust MFCL log interpretation must be conducted. Wear is commonly measured by comparing the results of a MFCL to a base MFCL, which ideally was taken at the beginning of the section. In the standard process, the maximum measured diameters per joint of both MFCLs are compared. A more accurate single run-MFCL interpretation methodology will be presented, which relies on statistical analysis of the casing shape.
It was found that the standard MFCL interpretation methodology may be the weak link in the chain. The standard methodology led to significant exaggeration of the wear factor(s), especially if the calibration was done based on mild levels of wear. Casing wear prediction remains a complex issue, due to uncertainties concerning wear and friction factor. The new MFCL calibration methodology, including a robust stiff-string torque and drag model, is capable of significantly reducing the levels of uncertainty. Overall the complete methodology is the basis for accurate wear prediction and reduces the need of casing over-engineering.
Evaluation of Efficiency Gas EOR Techniques Using Advanced PVT-model
Authors: Semenov A.A. , Allouti A. 
Published: November 2016

Abstract
Conventional way of building PVT-models of reservoir fluids consists of creating the simplistic so-called black-oil model. Results from PVT laboratory (fluid densities, bubble-point pressure, GOR, etc…) are using as input data for PVT correlations. All other properties of the reservoir fluids are calculated from widely known PVT correlations. But simplistic black-oil models were not designed for the modelling of change of fluid state (oil to gas and vice versa). Also black-oil models are not capable to simulate effects on the oil-gas contact.
In order to overcome above mentioned issues, compositional PVT-models have been introduced. These models solve equation of state (EOS) for each component. They add number of equations to the numerical simulator (lumping procedure could be introduced), but allow to accurately simulate effects on the gas-oil contact and transfet of one hydraucarbon phase to another. But usually a few results of fluid analysis are availbale and the question is: how to use all those results to build a non contradictive PVT model which is in line with all PVT experiments results?
In order to overcome this challenge, the workflow for quality control (QC) and analysis of fluid PVT data is proposed. That workflow was used to analyse data from reservoirs an Abu Dhabi Offshore field. After selection and cleaning of data set, the lumping of initially broad composition (C36+) was executed. Then regression algorithms from commercially available software have been used to match lumped composition properties with results of PVT experiments. Results of PVT experiments from other wells were used as a blind test for derived composition.
Value at Risk VaR of Dynamic Crude Oil Prices for Project Risk and Economics – Application of Extreme Value Theory EVT and Peak-Over-Threshold POT Model
Authors: Nurhadi Sudirman Rasmin 
Published: November 2016

Abstract
This paper applies Peak Over Threshold (POT) model of extreme value theory, using Generalized Pareto Distribution (GPD) which can give more accurate description on long-heavy-tailed distribution of crude oil prices dynamics. The baseline data are long-run series of historical daily spot prices (WTI and Brent) and basket prices (OPEC). Since the focus is risk perspective of oil producers, this study exercises the loss value of crude oil prices, negative difference of a particular day with previous one.
Value at Risk (VaR) is empirically quantified based on on historical trends, volatility and correlation to estimate the likelihood that given losses will exceed a certain amount. The threshold are determined by sample mean excess function, while General Pareto Distribution (GPD) estimators are obtained using Probability Weighted Moments (PWM) method. Econometric statistics software is used for auto-correlation and heteroscedasticity test of pre-treated raw data, while backtesting of VaR result used Kupiec Proportion of Failure Test and Loglikehood Ratio approach.
The focus is to apply modern method of risk assessment, providing an alternative tool / methodology of quantitative risk analysis for company E&P projects, especially during dynamic-oil-price environment.
Unlocking Ultra Tight Gas Reservoirs – Cased-Hole Mini DST with Wireline Formation Tester – A Case Study of Longest Pumping Time ever in Pakistan
Authors: Bari Abdul , Samir Magdy , Dar Usman , Zubair Talha , Javed Qasim , Shah Syed Firasat , Aslam Muhammad Adeel , Khan Imran , Siddique Faisal Anwar 
Published: November 2016

Abstract
Formation testers are being widely used worldwide in open hole, especially in exploratory wells where fluid identification, downhole sampling, determining pressure and mobilities are very critical. Sometimes, due to tight formations, unconsolidated sands or excessive borehole washouts/breakouts, it is not advisable to pump, because with longer stationary times there is high risk of differential sticking. In this scenario, cased-hole formation tester comes into play. The whole operation involves perforating 1 foot interval in casing, then isolating the perforated interval with straddle packers (3.28 ft or 1m apart). This is followed by pumping to establish fluid type and representative sampling. Later, extended buildup is acquired for reservoir characterization until transient reaches the radial flow regime (Mini-DST).
Well A is located in XYZ Block, Pakistan and is operated by Pakistan Petroleum Limited (PPL).Pressures and mobilities were obtained with wireline formation testing probe module across open-hole which found the formation to be ultra-tight. Pumpout could not be acquired with probe module due to formation tightness, therefore the question of fluid type was unanswered. Additionally, across the prospective zone washouts were observed. Due to these factors, the well was cased to establish fluid type and reservoir characterization (permeability, skin and pressure) through cased-hole dual packer formation tester. After 10 hours of pumping, first gas breakthrough was observed on downhole fluid analyzer. Pumping was carried out for almost 22 hours in order to get representative samples. This was the longest pumping time ever on any well in Pakistan. Later, buildup was acquired since hydrocarbon presence was established (Mini-DST).
Cased-hole formation testing is very helpful when dealing with layered reservoirs as testing of each individual layer on a full-fledge DST operation would be very costly, especially if the layers end up being declared as water bearing. Similarly, conventional DST operation for ultra-tight formations can cost a lot of rig days, whereas mini-drillstem testing can conclude the same with reasonable amount of rig time. The most important benefit of cased-hole formation testing is its capability to pump for longer durations with no risk of differential sticking, thereby expanding the possibilities for formation testing and sampling.
AASP flooding as a Substitute of ASP Flooding for Chemical EOR in Carbonate Reservoirs
Authors: Kalwar S. A. , Elraies K. A. , Abbas G. , Kumar S. , Farouque K. 
Published: November 2016

Abstract
Alkali-Surfactant-Polymer (ASP) flooding is the most effective Chemical Enhanced Oil Recovery (CEOR) method applied in sandstone reservoirs. After the successful results in sandstone formations, its usage has been widened to carbonate reservoirs as well. However, ASP application in carbonate reservoirs is less well understood. The main limitation of ASP flooding in carbonate reservoirs is the presence of carbonate minerals. These minerals react with the added chemicals to form insoluble materials called precipitations. Therefore, an ASP formulation was developed by incorporating acrylic acid as a precipitation inhibitor to overcome the precipitation problems.
The performance of the Acrylic Acid (AA) with an ASP formulation was evaluated using sodium metaborate, surfactant and polymer. Feasibility of applying AA with ASP formula was demonstrated by comprehensive fluid-fluid compatibility tests, interfacial tension tests, viscosity measurements and coreflooding experiments. Hardbrine composition of 59,940 ppm was used to prepare the ASP formulations in the presence and absence of AA. All the chemicals including, alkalis, surfactants, and polymers were compatible with the hard brine used in this study. The presence of acrylic acid exhibited excellent properties in preventing precipitations as the all solutions remained clear for 30 days at 80°C.
The weight ratio of optimum acid concentration of acid to alkali was found to be 0.6:1.0. No precipitation was observed when using this acid to alkali ratio. Interfacial tension and viscosity tests screened the best chemical formulations which were validated by coreflooding. The core flooding tests showed significant improvement in the oil recovery with the use of AASP and ASP flooding by accomplishing a total oil recovery of 75.7% and 88.7% OOIP respectively.
Although, total recovery efficiency of AASP formulation is relatively lower than with ASP, the new AASP formulation can be prepared with any water source such as formation water or seawater. The precipitation inhibitor makes the conventional ASP system more flexible and advantageous for offshore applications by eliminating the need of softening or desalting the seawater. Furthermore, there is no need to remove the calcium and magnesium ions from the injected water as it can be done by using the appropriate concentration of acid and alkali. This eliminates the cost of water treatment equipment and minimizes the use of surface equipment as well.
Glucose Metabolism After Gastric Banding and Gastric Bypass in Individuals With Type 2 Diabetes: Weight Loss Effect
Authors: Holter Marlena M. , Dutia Roxanne , Stano Sarah M. , Prigeon Ronald L. , Homel Peter , McGinty James J. , Belsley Scott J. , Ren Christine J. , Rosen Daniel , Laferrère Blandine 
Published: November 2016

OBJECTIVE
The superior effect of Roux-en-Y gastric bypass (RYGB) on glucose control compared with laparoscopic adjustable gastric banding (LAGB) is confounded by the greater weight loss after RYGB. We therefore examined the effect of these two surgeries on metabolic parameters matched on small and large amounts of weight loss.

RESEARCH DESIGN AND METHODS
Severely obese individuals with type 2 diabetes were tested for glucose metabolism, β-cell function, and insulin sensitivity after oral and intravenous glucose stimuli, before and 1 year after RYGB and LAGB, and at 10% and 20% weight loss after each surgery.

RESULTS
RYGB resulted in greater glucagon-like peptide 1 release and incretin effect, compared with LAGB, at any level of weight loss. RYGB decreased glucose levels (120 min and area under the curve for glucose) more than LAGB at 10% weight loss. However, the improvement in glucose metabolism, the rate of diabetes remission and use of diabetes medications, insulin sensitivity, and β-cell function were similar after the two types of surgery after 20% equivalent weight loss.

CONCLUSIONS
Although RYGB retained its unique effect on incretins, the superiority of the effect of RYGB over that of LAGB on glucose metabolism, which is apparent after 10% weight loss, was attenuated after larger weight loss.
Translation, Cross-cultural Adaptation, and Clinimetric Testing of Instruments Used to Assess Patients With Ankle Sprain in the Brazilian Population
Authors: da Cunha Ronaldo Alves , Hazime Fuad Ahmad , da Silva Martins Maria Cecília , Ferreira Mateus , de Castro Pochini Alberto , Ejnisman Benno 
Published: November 2016

Study Design Clinical measurement study. Background Ankle sprain is a common condition. Therefore, translated, culturally adapted, and clinimetrically tested instruments for measuring the ankle are needed. Objectives To translate and cross-culturally adapt the Sports Athlete Foot and Ankle Score (SAFAS) and the global rating of change (GROC) into Brazilian Portuguese. This study also aimed to test the measurement properties of the SAFAS, the GROC, and the existing Brazilian-Portuguese versions of the numeric pain-rating scale (NPRS) and the ankle-hindfoot scale of the American Orthopaedic Foot and Ankle Society (AOFAS) in a group with ankle sprain. Methods The SAFAS and GROC instruments were cross-culturally adapted into Brazilian Portuguese and pretested in this population (n = 18). The measurement properties of the SAFAS, GROC, NPRS, and AOFAS (internal consistency, ceiling and floor effects, construct validity, reproducibility, and responsiveness) were tested in a test-retest design in patients with ankle sprain at baseline (n = 63) and at follow-up periods of 48 to 72 hours (n = 53) and 4 weeks (n = 43) after baseline. Results The SAFAS, GROC, NPRS, and AOFAS yielded considerable internal consistency (Cronbach alpha ranging from .76 to .97), moderate reliability (intraclass correlation coefficient model 2,1 ranging from 0.59 to 0.80), and dubious agreement (percentage of the standard error of measurement ranging from 13% to 22.43%). The highest correlations on construct validity were observed among the 4 SAFAS subscales (Pearson r = 0.75 to 0.86, P<.01), but statistically significant values appeared in the intercorrelation of instruments. There were no observed floor or ceiling effects in any of the instruments. All of their scores of change showed moderate correlation with the GROC (r = −0.48 to 0.30, P<.05) and could be classified as responsive. Conclusion The Brazilian-Portuguese versions of the SAFAS, GROC, NPRS, and AOFAS had acceptable measurement properties in high-performing athletes. J Orthop Sports Phys Ther 2016;46(12):1042–1050. Epub 8 Nov 2016. doi:10.2519/jospt.2016.6218
Placing Wellbeing
Authors: Ferraro Emilia , Barletti Juan Pablo Sarmiento 
Published: November 2016

AbstractIn this thematic issue we offer anthropologically-informed snapshots of the different forms that wellbeing takes when approached from place-based perspectives. We are interested in highlighting and engaging with the undermining of place in the literature on wellbeing, which has produced a lack of appreciation for the role that culture plays in forming and informing different discourses, understandings and practices of wellbeing, as well as wellbeing scholarship itself. Our articles examine place as part of a project that aims at generating new contexts from which to ‘think otherwise’ about social policy, politics, the creation of knowledge, and, ultimately, existence.
Home and Away
Authors: Thin Neil 
Published: November 2016

AbstractWorldwide, people’s attachments to places are typically ambivalent, and complemented by desires for mobility and scene-changing. So to understand relationships between place and wellbeing, we need to look beyond the simple idea that some kinds of place, local characteristics and place attachments make people’s lives go better. Places matter, but wellbeing is not environmentally determined, it is a complex outcome of lifelong interactions between people and places. Some of these are conscious and deliberate, and some involve deliberate relocation as well as processes of attachment. This article supplements the environmental determinism of ‘good place’ theories, and the social constructionism of ‘healthy place attachment’ theories, with recommendations for a systematic approach to mapping and analysing how wellbeing happens. It pays particular attention to deliberate ‘place appreciation’, which refers to these dynamic interactions through which people actively derive value from places. Ethnographic examples of deliberate ecological self-improvement in later life are explored to highlight three kinds of place-related wellbeing strategies: place-making, local mobility and relocation. A simple analytical system is proposed to highlight the potential relevance to policy and practice of a systematic sociocultural ecology of wellbeing.
Teachings of Tara
Authors: Miles-Watson Jonathan 
Published: November 2016

AbstractThis article presents the case for a rethinking of the academy’s approach to sacred space through a demonstration of the way that a focus on unskilled actors reconfigures established approaches and interpretations. The article opens with an auto-ethnographic account of the powerful effect of Shimla’s Tara Devi temple on personal wellbeing and from this starting point spirals out to explore how Tara (and her sacred places) are connected to wellbeing both in the Himalayan region of Shimla and beyond. Through this process, arguments that I have previously made, concerning both the relation of sacred places to happiness (2010) and the way that sacred places operate in Himalayan North India (2012), are significantly complicated, leading to a reappraisal of the role that unskilled actors play in the constitution of sacred space. The article concludes by drawing these ethnographic reflections and theoretical considerations together to develop a key set of recommendations that call for policy-makers to engage sensitively with sacred places in the contemporary, post-secular city.
The role of Phragmites in the CH4 and CO2 fluxes in a minerotrophic peatland in southwest Germany
Authors: van den Berg Merit , Ingwersen Joachim , Lamers Marc , Streck Thilo 
Published: November 2016

Abstract. Peatlands are interesting as a carbon storage option, but are also natural emitters of the greenhouse gas methane (CH4). Phragmites peatlands are particularly interesting due to the global abundance of this wetland plant (Phragmites australis) and the highly efficient internal gas transport mechanism, which is called humidity-induced convection (HIC). The research aims were to (1) clarify how this plant-mediated gas transport influences the CH4 fluxes, (2) which other environmental variables influence the CO2 and CH4 fluxes, and (3) whether Phragmites peatlands are a net source or sink of greenhouse gases. CO2 and CH4 fluxes were measured with the eddy covariance technique within a Phragmites-dominated fen in southwest Germany. One year of flux data (March 2013–February 2014) shows very clear diurnal and seasonal patterns for both CO2 and CH4. The diurnal pattern of CH4 fluxes was only visible when living, green reed was present. In August the diurnal cycle of CH4 was the most distinct, with 11 times higher midday fluxes (15.7 mg CH4 m−2 h−1) than night fluxes (1.41 mg CH4 m−2 h−1). This diurnal cycle has the highest correlation with global radiation, which suggests a high influence of the plants on the CH4 flux. But if the cause were the HIC, it would be expected that relative humidity would correlate stronger with CH4 flux. Therefore, we conclude that in addition to HIC, at least one additional mechanism must be involved in the creation of the convective flow within the Phragmites plants. Overall, the fen was a sink for carbon and greenhouse gases in the measured year, with a total carbon uptake of 221 g C m−2 yr−1 (26 % of the total assimilated carbon). The net uptake of greenhouse gases was 52 g CO2 eq. m−2 yr−1, which is obtained from an uptake of CO2 of 894 g CO2 eq. m−2 yr−1 and a release of CH4 of 842 g CO2 eq. m−2 yr−1.
Automated Analysis of Orthopaedic X-ray Images based on Digital-Geometric Techniques
Authors: Bandyopadhyay Oishila , Biswas Arindam , Bhattacharya Bhargab B. 
Published: November 2016

This thesis reports several methods for automated analysis and interpretation of bone X-ray images. Automatic segmentation of the bone part in a digital X-ray image is a challenging problem because of its low contrast against the surrounding flesh. In this thesis, we propose a fully automated X-ray image segmentation technique, which is based on a variant of entropy measure of the image. We have also analyzed the geometric information embedded in the long-bone contour image to identify the presence of abnormalities in the bone and perform fracture detection, fracture classification, and bone cancer diagnosis.
La derecha también ríe. El humor gráfico en la revista El Caudillo de la Tercera Posición
Authors: Besoky Juan Luis 
Published: November 2016

Este trabajo presenta un estudio del humor gráfico de la revista peronista El Caudillo de la Tercera Posición.Esa revista fue editada entre 1973 y 1975 como un semanario de información política y se convirtió en una publicación emblemática del peronismo de derecha. De allí se combatió y denunció la “infiltración”de la izquierda. Desde sus primeros números incluyó una sección fija de humor con caricaturas y tiras cómicas. Es a través del análisis de la sección de humor que se hace posible entender la cultura política de la derecha peronista y los estereotipos que esta construyó sobre sus enemigos. Palabras clave: Humor; Derecha; Anticomunismo; Peronismo.