bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterisation of incinerator ash treated expansive soils
Authors: Al-Rawas A. A. 
Published: November 2009

This paper investigates the physical, engineering, chemical and microfabric characteristics of two soils from Oman treated with incinerator ash produced at Sultan Qaboos University. First, the physical, engineering and chemical properties of the incinerator ash and the soils used were determined. The soils were then mixed with the incinerator ash at 0%, 10%, 15%, 20%, 25% and 30% by dry weight of the soils. Liquid limit and plastic limit tests were performed on specimens after 24 h of curing, whereas tests for swell per cent and direct shear were carried out on specimens cured for 1, 7 and 14 days. In addition, scanning electron microscope micrographs of representative treated samples were taken to examine the microfabric changes caused by the addition of the incinerator ash. The results showed that the incinerator ash used was a non-hazardous waste material. All treated samples showed a reduction in swell per cent and cohesion, and an increase in angle of internal friction with the addition of incinerator ash for all curing periods. The use of 20% and 30% additive showed clearly the development of aggregations that contributed to reduction of swell per cent of the soils. Cet exposé é tudie les caractéristiques physiques, mécaniques, chimiques et microstructurales de deux sols d'Oman traités à la cendre d'incinérateur provenant de l'Université Sultan Qaboos. Tout d'abord, nous avons déterminé les propriétés physiques, mécaniques et chimiques de la cendre d'incinérateur et des sols utilisés. Ces sols ont ensuite é té mélangés à de la cendre d'incinération dans des proportions de 0%, 10%, 15%, 20%, 25% et 30% du poids à sec des sols. Nous avons réalisé des essais de limite liquide et de limite plastique sur des spécimens après 24 h de cuisson; nous avons réalisé les tests de gonflement et de cisaillement direct sur des spécimens cuits pendant 1, 7 et 14 jours. De plus, nous avons fait des micrographes par microscope é lectronique à balayage sur les é chantillons représentatifs traités afin d'examiner les changements de microstructure causés par l'adjonction de la cendre d'incinération. Les résultats ont montré que la cendre d'incinération utilisée était une matière de récupération non dangereuse. Tous les é chantillons traités ont montré une réduction du pourcentage de gonflement et de la cohésion ainsi qu'une augmentation de l'angle de friction interne lors de l'adjonction de la cendre d'incinération pendant toutes les périodes de cuisson. L'utilisation de 20% et de 30% d'additifs a montré clairement le développement d'agrégations qui ont contribué à la réduction du pourcentage de gonflement des sols.
Stabilisation of rice husk ash for use as cushion below foundations on expansive soils
Authors: Sivapullaiah P. V. , Subba Rao K. S. , Gurumurthy J. V. 
Published: November 2009

Placing a cushion between the expansive soil and the foundation is an attractive proposal for overcoming the problems associated with construction of structures over expansive soils such as Indian black cotton soil. Extensive studies on cohesive non-swelling soil as a cushion have shown that it is ineffective over cycles of swelling and shrinkage of soil. The present paper explores the possibility of using rice husk ash (RHA) as a cushion. It was found that RHA stabilised with 3–9% of lime (LSR) or 10% of cement (CSR) and cured for about a week develops the properties required for an effective cushion material. Stabilised RHA reduces the bandwidth of vertical movements in expansive soil not only during the first cycle of swelling but also during subsequent cycles of swelling and shrinkage. The reduction increases with the thickness of the cushion. However, it is found that the middle level between the equilibrium swollen and equilibrium shrunken levels, called the operating level, decreases with the use of LSR/CSR as a cushion. LSR is more effective than CSR.Le fait de placer un coussin entre un sol expansif et une fondation est une proposition intéressante pour venir à bout des problèmes associés à la construction de structures sur des sols expansifs comme le sol de coton noir indien. Des études poussées sur le sol cohésif non gonflant employé comme coussin ont montré qu'il n'a aucun effet sur des cycles de gonflement et de rétrécissement du sol. Cet exposé explore la possibilité d'utiliser de la cendre d'enveloppe de grains de riz (RHA) comme coussin. Nous avons trouvé que le RHA stabilisé avec 3 à 9 % de chaux (LSR) ou 10 % de ciment (CSR) et cuit pendant environ une semaine développait les propriétés nécessaires pour former un coussin efficace. Le RHA stabilisé réduit la largeur de bande des mouvements verticaux dans le sol expansif, non seulement pendant le premier cycle de gonflement mais aussi pendant les cycles ultérieurs de gonflement et rétrécissement. La réduction augmente en même temps que l'épaisseur du coussin. Cependant, il est apparu que le niveau moyen entre les niveaux d'équilibre gonflé et d'équilibre rétréci, appelé niveau opératoire, diminuait avec l'utilisation du LSR/CSR comme coussin. Le LSR s'est révélé plus efficace que le CSR.
Plastic limit and compaction characteristics of finegrained soils
Authors: Sridharan A. , Nagaraj H. B. 
Published: November 2009

Laboratory determination of the compaction characteristics of soils is important for use in earthwork constructions. The purpose of compacting earth fills such as earth dams and embankments (highway, railway and canal) is to produce a soil mass that will satisfy the two basic criteria: reduction in settlement and increase in shear strength. For preliminary design and assessment, correlations with the liquid limit have been attempted by various investigators. However, from the present study it is seen that the correlations are not up to a satisfactory level. In this paper the results of detailed investigations carried out are examined to find which of the index properties correlate well with the compaction characteristics. In the analysis, apart from the authors' experimental results, results from the available literature have also been considered. It is found that the plastic limit bears a good correlation with the compaction characteristics, namely optimum moisture content and maximum dry unit weight, much better than liquid limit or plasticity index. La détermination en laboratoire des caractéristiques de compaction des sols est importante pour les constructions à terrassement. Les remblais de terre compactée comme les levées de terre et les talus (autoroutes, voies ferrées et canaux) ont pour but de produire une masse de sol qui satisfera deux critères de base: la réduction du tassement et l'amélioration de la résistance au cisaillement. Pour la conception préliminaire et l'évaluation, divers chercheurs ont tenté d' établir des corrélations avec la limite liquide. Cependant, cette étude montre que les corrélations ne sont pas d'un niveau satisfaisant. Dans cet exposé, nous examinons les résultats de ces recherches détaillées afin de trouver celles des propriétés indice qui correspondent le mieux aux caractéristiques de compaction. Dans cette analyse, outre les résultats expérimentaux obtenus par les auteurs, les résultats disponibles publiés ont é galement é té pris en compte. Nous avons trouvé que la limite plastique montre une bonne corrélation avec les caractéristiques de compaction, nommément la teneur en eau optimum et le poids unitaire sec maximum, bien mieux qu'avec l'indice de limite liquide ou l'indice de plasticité.
Quality control in Central Japan International Airport construction
Authors: Kitazume M. , Satoh T. 
Published: November 2009

Recently, a pneumatic flow mixing method has been developed for sea reclamation and land development, in which soft soil is mixed with a relatively small amount of stabilising agent in a transporting pipe. The soil mixture forms several separated mud plugs in the pipe, and is thoroughly mixed with the help of turbulent flow during transportation. This method was adopted to construct part of a man-made island for the Central Japan International Airport at the Ise Bay area in Nagoya. In the construction project, a total of 8.6 million m3 of dredged soil was stabilised by the method for sea reclamation. During the construction, quality control and assurance of manufacturing the treated soil were carried out with an automated control system and laboratory tests on sampled soils. In this paper, the quality control system developed in this project and the quality assurance of the improved ground are described in detail. Récemment, une méthode de mixage á flux pneumatique a été développée pour récupérer des terrains sur la mer et les développer, méthode consistant à mélanger un sol tendre avec une quantité relativement faible d'agents stabilisants dans une canalisation de transport. Le mélange de terre forme plusieurs bouchons de boue séparés dans la canalisation et se trouve mélangé à l'aide d'un flux turbulent pendant le transport. Cette méthode a été adoptée pour construire une partie d'une île artificielle pour l'aéroport international Central Japan dans la région de Ise Bay ´ Nagoya. Dans le projet de construction, un total de 8,6 millions de m3 de sol draguéa été stabilisé par cette méthode. Pendant la construction, le contrîle et l'assurance qualité concernant la fabrication de sol traité ont été effectués par un systéme de contrîle automatisé et des essais en laboratoire suré chantillons de sol. Dans cet exposé, nous décrivons en détail le systéme de contrîle de la qualité développé dans ce projet ainsi que l´assurance qualité du sol amélioré.
Mechanisms of Enhanced Natural Imbibition With Novel Chemicals
Authors: Zhang Jieyuan , Nguyen Quoc P. , Flaaten Adam K. , Pope Gary A. 
Published: November 2009

Summary
A large body of literature has reflected an extensive experimental study of natural imbibition driven by local capillary pressures at high interfacial tension (IFT). However, water imbibition induced by emulsification at low IFT is not well understood. Recently, anionic surfactants have been shown to induce imbibition in mixed- and oil-wet carbonates. Sodium carbonate has been used to reduce the surfactant adsorption. However, calcium and other divalent cations can cause precipitation of the alkali unless soft water is used. This is a significant limitation of sodium carbonate. The present research both advances our understanding of the use of chemicals to enhance oil recovery (EOR) from fractured carbonate reservoirs and indicates how the process can be optimized using novel chemicals. This research applies to the improvement of oil recovery from mixed- and oil-wet fractured carbonate reservoirs.
We show how to select and evaluate new chemicals as natural imbibition enhancers in carbonate rocks. A novel experimental method has also been developed to quantify the significance of capillary and emulsification driven imbibition because of the presence of the chemical imbibition enhancers. An in situ imbibition profile was visualized using a computed tomography (CT) X-ray scanning technique. The results show that formation of microemulsion strongly promotes water imbibition. The rate was highest for Winsor Type II microemulsion and lowest for Winsor Type I microemulsion. The alkalis exhibited a striking imbibition enhancement driven mainly by alteration of capillary pressure. The performance of the imbibition enhancers was found to be consistent for different core-plug sizes and boundary conditions. A novel alkali has been tested that shows a high tolerance for hardness and, thus, may be a good alternative to sodium carbonate under some conditions.
The application of low-cost chemicals to EOR from fractured carbonates is an extremely significant development owing to the vast volumes of oil in such reservoirs and the lack of practical alternative methods of recovering such oil.
Field Applications of Capacitance-Resistance Models in Waterfloods
Authors: Sayarpour M. , Kabir C. S. , Lake L. W. 
Published: November 2009

Summary
Application of fast, simple and yet powerful analytic tools, capacitance-resistance models (CRMs), is demonstrated with four field examples. Most waterfloods lend themselves to this treatment. This spreadsheet-based tool is ideally suited for engineers who manage daily flood performance. We envision CRM application to precede any detailed full-field numerical modeling.
We have selected field case studies in a way to demonstrate CRM capabilities in different settings: a tank representation of a field, its ability to determine connectivity between the producers and injectors, and understanding flood efficiencies for the entire field or a portion of a field.
Significant insights about the flood performance over a short time period can be gained by estimating fractions of injected fluid being directed from an injector to various producers and the time taken for an injection signal to reach a producer. Injector-to-producer connectivity may be inferred directly during the course of error minimization. Because the method circumvents geologic modeling and saturation matching, it lends itself to frequent usage without intervention of expert modelers.
Comparison of Stochastic Sampling Algorithms for Uncertainty Quantification
Authors: Mohamed Linah , Christie Mike , Demyanov Vasily 
Published: November 2009

Summary
History matching and uncertainty quantification are two important research topics in reservoir simulation currently. In the Bayesian approach, we start with prior information about a reservoir (e.g., from analog outcrop data) and update our reservoir models with observations (e.g., from production data or time-lapse seismic). The goal of this activity is often to generate multiple models that match the history and use the models to quantify uncertainties in predictions of reservoir performance. A critical aspect of generating multiple history-matched models is the sampling algorithm used to generate the models. Algorithms that have been studied include gradient methods, genetic algorithms, and the ensemble Kalman filter (EnKF).
This paper investigates the efficiency of three stochastic sampling algorithms: Hamiltonian Monte Carlo (HMC) algorithm, Particle Swarm Optimization (PSO) algorithm, and the Neighbourhood Algorithm (NA). HMC is a Markov chain Monte Carlo (MCMC) technique that uses Hamiltonian dynamics to achieve larger jumps than are possible with other MCMC techniques. PSO is a swarm intelligence algorithm that uses similar dynamics to HMC to guide the search but incorporates acceleration and damping parameters to provide rapid convergence to possible multiple minima. NA is a sampling technique that uses the properties of Voronoi cells in high dimensions to achieve multiple history-matched models.
The algorithms are compared by generating multiple history- matched reservoir models and comparing the Bayesian credible intervals (p10-p50-p90) produced by each algorithm. We show that all the algorithms are able to find equivalent match qualities for this example but that some algorithms are able to find good fitting models quickly, whereas others are able to find a more diverse set of models in parameter space. The effects of the different sampling of model parameter space are compared in terms of the p10-p50-p90 uncertainty envelopes in forecast oil rate.
These results show that algorithms based on Hamiltonian dynamics and swarm intelligence concepts have the potential to be effective tools in uncertainty quantification in the oil industry.
Combined Underground Gas Storage and Enhanced Oil Recovery in a Fractured Reservoir
Authors: de Kok Joop , Clemens Torsten 
Published: November 2009

Summary
The Schönkirchen Tief reservoir is located in the Vienna basin. The reservoir contained 19 std m3 oil originally in place. The current recovery factor after 45 years of production is 59%. The field was produced by water injection. The wells, located at the crest of the high relief structure are exhibiting a high water cut. In 2006–07, a comprehensive study was performed to optimize the future development of the field.
The field is made up of different types of dolostones. The lower part of the field consists of fractured dolomite, the upper part of weathered dolomite and dolomite debris. A dual-permeability model was used to simulate the flow in the dolomite and the weathered zone, whereas a single-permeability model was sufficient for the debris.
The main recovery mechanisms for this reservoir are imbibition and water/oil gravity drainage. Laboratory experiments indicated that the dolomite is water-wet to mixed-wet at reservoir conditions of 100°C.
The results of the study show that an economically attractive option for the field development is establishing an underground gas storage (UGS) and using the injected gas to increase the oil recovery. Because of the fact that the current reservoir pressure is below initial pressure, within half a year, approximately 1 billion std m3 can be injected. Only approximately one-third of this gas has to remain as cushion gas during the first cycle. To further increase the amount of gas that can be used for UGS, fluids have to be withdrawn from the reservoir. Drilling horizontal wells close to the original oil/water contact enables injection of an additional 2 billion std m3 gas.
The gas injection leads to gas/oil gravity drainage of the oil and water present in the matrix of the fractured reservoir. The oil is collected by the horizontal wells, resulting in incremental oil recovery of up to 5% of oil originally in place.
Monitoring and Control of Drilling Utilizing Continuously Updated Process Models
Authors: Iversen F. P. , Cayeux E. , Dvergsnes E. W. , Gravdal J. E. , Vefring E. H. , Mykletun B. , Torsvoll A. , Omdal S. , Merlo A. 
Published: November 2009

Abstract
Recent developments in drilling technology, such as increased sensory information, enhanced data processing and transmitting capacity and capability, and developments in computer controlled machinery, together with adaptation of already available process technology and know-how, are opening up new possibilities for drilling operations. Application of these combined technologies, together with advanced computer modeling, enables enhanced monitoring and increased optimization and control of drilling operations. This paper presents such an integrated system for monitoring and control of the drilling process, currently in the test phase.
A key element in the methodology used here is that the models for fluid flow and drilling mechanics are continuously updated in real-time according to the measured data using Kalman filtering techniques. By comparing the calibrated models to real-time data, unwanted occurrences can be detected quickly, and mitigating actions may be taken, either through system control or through manual intervention.
Using the calibrated models, safe limits for the drilling operation are computed and enforced, and procedures are optimized. The modules developed cover tripping and reaming, pump start up, friction tests, stick-slip prevention, bit load optimization and monitoring.
The methodology may be applied to drilling operations where the drilling equipment is computer controlled. Surface and preferably downhole data must be available in real time. Rigorous testing with drilling data from offshore drilling operations has been performed, and several full-scale tests have been run on a test rig. The ability to maintain the drilling operation within critical limits has been demonstrated. The methodology may contribute to increased safety and reduced down time during drilling operations.
Deleterious Associations of Sitting Time and Television Viewing Time With Cardiometabolic Risk Biomarkers
Authors: Thorp Alicia A. , Healy Genevieve N. , Owen Neville , Salmon Jo , Ball Kylie , Shaw Jonathan E. , Zimmet Paul Z. , Dunstan David W. 
Published: November 2009

OBJECTIVE
We examined the associations of sitting time and television (TV) viewing time with continuously measured biomarkers of cardio-metabolic risk in Australian adults.

RESEARCH DESIGN AND METHODS
Waist circumference, BMI, resting blood pressure, triglycerides, HDL cholesterol, fasting and 2-h postload plasma glucose, and fasting insulin were measured in 2,761 women and 2,103 men aged ≥30 years (mean age 54 years) without clinically diagnosed diabetes from the 2004–2005 Australian Diabetes, Obesity and Lifestyle (AusDiab) study. Multivariate linear regression analyses examined associations of self-reported sitting time and TV viewing time (hours per day) with these biomarkers, adjusting for potential confounding variables.

RESULTS
For both women and men, sitting time was detrimentally associated with waist circumference, BMI, systolic blood pressure, fasting triglycerides, HDL cholesterol, 2-h postload plasma glucose, and fasting insulin (all P &lt; 0.05), but not with fasting plasma glucose and diastolic blood pressure (men only). With the exception of HDL cholesterol and systolic blood pressure in women, the associations remained significant after further adjustment for waist circumference. TV viewing time was detrimentally associated with all metabolic measures in women and all except HDL cholesterol and blood pressure in men. Only fasting insulin and glucose (men only) remained deleteriously associated with TV viewing time after adjustment for waist circumference.

CONCLUSIONS
In women and men, sitting time and TV viewing time were deleteriously associated with cardio-metabolic risk biomarkers, with sitting time having more consistent associations in both sexes and being independent of central adiposity. Preventive initiatives aimed at reducing sitting time should focus on both nonleisure and leisure-time domains.
Postprandial Diabetic Glucose Tolerance Is Normalized by Gastric Bypass Feeding as Opposed to Gastric Feeding and Is Associated With Exaggerated GLP-1 Secretion
Authors: Dirksen Carsten , Hansen Dorte L. , Madsbad Sten , Hvolris Lisbeth E. , Naver Lars S. , Holst Jens J. , Worm Dorte 
Published: November 2009

OBJECTIVE
To examine after gastric bypass the effect of peroral versus gastroduodenal feeding on glucose metabolism.

RESEARCH DESIGN AND METHODS
A type 2 diabetic patient was examined on 2 consecutive days 5 weeks after gastric bypass. A standard liquid meal was given on the first day into the bypassed gastric remnant and on the second day perorally. Plasma glucose, insulin, C-peptide, glucagon, incretin hormones, peptide YY, and free fatty acids were measured.

RESULTS
Peroral feeding reduced 2-h postprandial plasma glucose (7.8 vs. 11.1 mmol/l) and incremental area under the glucose curve (iAUC) (0.33 vs. 0.49 mmol · l−1 · min−1) compared with gastroduodenal feeding. β-Cell function (iAUCCpeptide/Glu) was more than twofold improved during peroral feeding, and the glucagon-like peptide (GLP)-1 response increased nearly fivefold.

CONCLUSIONS
Improvement in postprandial glucose metabolism after gastric bypass is an immediate and direct consequence of the gastrointestinal rearrangement, associated with exaggerated GLP-1 release and independent of changes in insulin sensitivity, weight loss, and caloric restriction.