bluuebunny/crossref_metadata_2025_split huggingface dataset:
Methods for Calculating Cartel Damages: A Survey
Authors: Maria Doose Anna 
Published: September 2014

Abstract
The paper focuses on the various methods used to quantify cartel damages, which have become more and more important as private damage suits in the aftermath of antitrust litigation increase. The approaches implementation is embedded into current legal environments with regards to the estimation approaches being used for quantification of cartel damages. The direct comparison of methods shows that difference methods convince due to their simplicity and plausibility in results as well as replicability. Cost-based approaches have to overcome hurdles but still are easy to conduct and comparatively more accurate. In contrast, price prediction takes market changes into account and the market simulation presents the most sophisticated and flexible approach, provided that assumptions are correct and correctly implemented, and therefore approaches the „real world“ counterfactual as approximate as possible.
Scaleup of Effective Mass Transfer in Vapour-Extraction Process Accounting for Field-Scale Reservoir Heterogeneities
Authors: Leung Juliana 
Published: September 2014

Summary
Vapour extraction (VAPEX) is a nonthermal process using vapourized solvents, with promising potential to reduce steam consumption in heavy-oil recovery. The key recovery mechanisms are convection and molecular diffusion enhanced by various spreading mechanisms [e.g., capillarity and velocity variations at the micro and macroscale (i.e., dispersion and mixing)]. The efficiency of diffusion/dispersion depends significantly on reservoir heterogeneities, which exhibit a wide range of length scales. This paper demonstrates a procedure for quantifying the scaling characteristics of effective mass transfer accounting for heterogeneities based on the volume-averaging approach. Volume averaging is a mathematical technique used to derive continuum equations at coarse scales given representative transport equations at fine scales. Although treatment of transport problems has been published in the past, application to stochastic geological systems is limited. In the proposed procedure, results from a fine-scale numerical flow simulation reflecting the full physics of VAPEX over a small element of the reservoir are integrated by use of the volume-averaging technique to provide effective description of mass transfer at the coarse scale. Scaling characteristics of effective mass transfer are investigated systematically for different heterogeneity distributions. Results show (1) spatial variability of effective-mass-transfer coefficients increases as a solvent chamber advances through the reservoir; (2) mean and variance of effective-mass transfer vary with length scale in a fashion similar to that of recovery statistics; and (3) variability in effective-mass transfer is a strong nonlinear function of heterogeneity. An original contribution is to provide a general framework for developing scaling relationships of effective mass transfer in VAPEX accounting for reservoir heterogeneities. It also presents an important potential in modelling of other solvent-injection applications. Results demonstrate that effective-mass transfer varies with length scale and heterogeneity; hence, it should be represented properly for accurate prediction of recovery performance in simulations using scaled-up reservoir models.
Pulse Amplitude Modulation Fluorometry Technique and Laboratory Cultivation of Qatari Corals: Studying Coral Growth and Photosynthetic Efficiency
Authors: Al-Naema Nayla , Saeed Suhur , Deb Nandita , Dupont Jennifer 
Published: September 2014

Abstract
The Arabian Gulf is well known as being probably the most extreme environment in which zooxanthellate coral reef communities occur. A combination of both extremely high and low temperatures as well as high salinities, combined with shallow profile of the coastal waters (high luminosity) imply high stress for coral physiology that may explain much of the coral bleaching events observed during the last decade. We proposed to investigate corals Symbiodinium response to different levels of those three elements. Among the different available methods; fluorescence technique (Imaging Pulse Amplitude Modulation - PAM) and buoyant weight were used to assess photosynthetic activity and health stress. Porites sp. samples were collected from two Qatari marine areas and exposed to high levels of the three essential elements in controlled laboratory conditions. Our results suggested that Imaging-PAM parameters (Maximum Quantum Yield Fv/Fm, Electronic Transfer Rate ETR, and Non-Photochemical Quenching NPQ) and growth gain percentage provided useful routine tools to detect stress situation in hospite Symbiodinium in Porites sp. Moreover, the high resolution images derived from PAM were able to capture the stress before it become visible to observer eyes. Elevated levels of temperature (38 °C) and salinity (50 psu) negatively influenced corals health and caused death events. Coral bleaching started after the sixth day of exposure suggesting that coral are affected only when extreme conditions persists for more than one week. With regards to raised light intensity, no stress was detected; in contrary growth and photosynthetic efficiency increased.
Critical Concentration of Foam and Enhanced Oil Recovery
Authors: Fejoli Rômulo Fieni , Romero Oldrich Joel 
Published: September 2014

Abstract
One of the most important tasks in Petroleum Engineering is the characterization of the properties of the reservoirs for the application of the method that will bring a greater oil recovery factor. Among the different special recovery methods with great potential for improving the oil recovery factor, the foam injection can be mentioned. The foam may be used as a selective block agent of the reservoir, which reduces the effective permeability zones already swept with high permeability. A widely used tool for this purpose is the simulation of petroleum reservoirs, which through the application of numerical methods allows for the solution of the hydraulic diffusivity equation. This project deals with the computational modeling of foam injection in oil reservoirs using a numerical software. The main objective of this research is to understand which are the parameters that maximize the oil recovery factor when the foam injection is used. Simulation results showed that the main acting parameters for the method of recovery are the oil viscosity and the concentration of surfactant for foam generation. The initial increases in surfactant concentration were that promoted a greater increase in oil production, achieving a recovery above of 30% of oil. Above a certain critical surfactant concentration of about 0.2 lb/stb the production increase was not significant.
Prediction of Horizontal Well Production Performance by Design of a Pressure Test of Partial Penetration in Heavy Oil Fields
Authors: Porlles J. W. 
Published: September 2014

Abstract
Recently, a big heavy oil province has been discovered in a remote area of the Amazonian rainforest in Peru. These fields tested heavy oil production (&lt; 12° API); commercial decision on developing this area will take into account results of drilling appraisal wells, evacuation of the heavy oil from the Peruvian jungle to the cost and environmental concerns in a high biodiversity region.
This study provides the necessary test design considerations to calculate, from a conventional pressure transient analysis, the timing for the start and the end of all the flow regimes happening in a partial penetration test; thus, some recommendations were drawn to reduce wellbore storage and ensure the hemispherical flow regime appears, as longer as possible during the test, to measure vertical permeability. A partial penetration test was carried out in an exploratory well supported by this methodology; anisotropy and productivity index was calculated. In addition, a comparison analysis was done to calculate dimensional productivity index and predict production performance for different well types by simulation, and precise decision-making process towards optimizing well trajectories for exploiting reservoirs to produce.
Thermal Expansion of Cement and Well Integrity of Heavy Oil Wells
Authors: Loiseau A.. 
Published: September 2014

Abstract
Proper well construction involves long-term integrity; thus, accurate characterization of the physical properties of set cement systems is mandatory. Chemical stability, compressive strength, and permeability are commonly the main parameters determined for oilfield cement systems. The knowledge of these properties is most often enough to estimate if a cement system will maintain well integrity. However, some hydrocarbon recovery processes are highly aggressive toward the cement sheath. Under thermal processes for recovery of heavy oil, such as steam-assisted gravity drainage (SAGD) or cyclic steam stimulation (CSS), the well temperature can reach up to 350°C. The casing expands during the heating-up phase, and this outward expansion increases the stress on the annular cement sheath. Under such conditions, simulations show that a key intrinsic thermal property, the linear coefficient of thermal expansion (LCTE), is equally as important as the other physical properties to maintain well integrity.
To determine the LCTE of set cement, one needs to understand the thermal-expansion theory of solid materials. An experimental setup for measuring this parameter for set cement has been developed, and essential precautions for performing accurate measurements have been formulated.
The LCTE of cement is a critical parameter in the development of new cement technologies for high-temperature (HT) well applications; the chemical composition of the cement system and the curing conditions can affect the LCTE of oilfield cement systems.
Improved understanding of this critical parameter has allowed significant improvement of the reliability of cement systems used in these hostile environments and provides better solutions in the form of thermally responsive cement systems.
Flow Assurance Applied Research Proposal for Heavy Oil Crudes from Green Offshore Naturally Fractured Reservoirs to Delivery Points
Authors: Camacho-Velázquez Rodolfo , Gómora-Figueroa A. Paulina , Cortés- Cortés Miguel , Pérez-Robles Víctor , Velázquez-Franco Martín 
Published: September 2014

AbstractThis paper presents a research project proposal to ensure the optimum flow assurance for the development of heavy crudes, from offshore reservoirs to delivey points, considering several field facilities, which include optimum application and performance of chemicals to suppress or attenuate the precipitation of organic and inorganic deposits, corrosion inhibitors, as well as the treatment of emulsions produced due to the presence of formation water during production. The interaction between chemicals employed in well stimulation treatments and those used for crude dehydration is also considered.This proposal intends setting the basis to optimize flow assurance by minimizing the chemical dosage in the production and transportation facilities, maximizing the useful life of the employed chemical products. In order to achieve this goal it is necessary to include;– Laboratory studies to characterize heavy oil, water and gas properties and the interactions between the different fluids present, which allow evaluating the generation and stability of emulsions, hidrocarbons stability, and corrosion index of water, for example. – Evaluation of chemicals for flow assurance in the reservoir, lifting fluids in production wells, including artificial lift systems, as well as surface transportation and treatment fluids, and the interaction between these chemicals at different points during hydrocarbons production. – Generation of reservoir, well completion, wellbore and surface transport models.Pressure analyses show that production is dominated by high porosity vugs, and that the vertical permeability of vuggy areas is relevant for fields sharing an aquifer due to water channeling and the possible formation of emulsions inside the reservoir in the reion close to the producing wells.The assessement of the aforedmentioned issues can lead to the control and/or prevention of emulsion formation, solids deposition and corrosion. Besides, addressing each of these issues individually, it is important to assess the influence of a mixture of several chemicals at the bottomhole and surface facilities, providing useful information to anticipate and avoid additional complications derived from the application of several chemicals to address flow assurance problems from the reservoir to the delivery points.
Green Products for Reducing the Viscosity of Heavy Oil
Authors: Rodrigues S.. , Oliveira A. P. , Pucciarelli N.. , Tooge C.. , Souza R.. 
Published: September 2014

Abstract
The production of heavy oil has emerged as one of the great challenges of the oil industry today. The high viscosity, characteristic of these oils is linked to factors such as the presence of higher molecular weight components, asphaltenes, paraffins, resins and even due to emulsion stability. Highly emulsified oils are seen as a big problem because it directly affects the oil production and the costs involved to do it. Already the phase behavior of asphaltenes has been the subject of discussion in various jobs that match to recognize its complexity. Thus it is of utmost importance to develop new technologies that act reducing the viscosity and consequently reflecting in higher yields with lower costs. This study aimed to develop products that act reducing the viscosity, in operations where asphaltene dispersion and controlled droplet size of emulsified water from the system increased, so as to promote a significant reduction in viscosity with the use of environmentally products correct. A sample of oil used in the tests was from an exploratory field onshore Colombia. Products containing mixtures of different green chemical-polymeric agents with the intention of promoting a multifunctional and excellent synergy with the proposed system were developed. The analyzes were performed oil viscosity in a Haake RS 600, wherein the oil had its SARA and its water content measured by Karl Fischer. The results obtained with viscosity reduction were highly significant and promising, as the oil used in this study, no previous treatment had a viscosity of approximately 180000 cP, and after the development and application of the product is reached viscosities of up to 25 cP, while optimizing the process of demulsification end of oil.
Design and Optimization of Orifice based Flow Control Devices in Steam Assisted Gravity Drainage: A Case Study
Authors: Kyanpour Mohammad , Chen Zhangxin 
Published: September 2014

The classical SAGD (Steam Assisted Gravity Drainage) involves drilling wells in parallel horizontal pairs. Steam is injected into the upper well (injector) to heat the reservoir and mobilize bitumen/heavy oil so that it drains to the lower well (producer) and can be lifted to the surface. In this process, steam distribution in the injector and a sustainable liquid level above the producer are key to achieve steam chamber conformance. The completion designs of these wells are critical in order to achieve optimal bitumen/heavy oil recovery and steam chamber development1.
Orifice based Flow Control Devices (FCDs) are being used in the SAGD wells. The FCDs in the injector (Steam Splitters) are used to customize steam distribution along the well. The FCDs in the producer (Inflow Control Devices) are used to develop a uniform inflow along the horizontal wellbore.
In this paper, a method will be presented for determining the size and position of Steam Splitters and Inflow Control Devices. This method can be used for both simple and complex reservoirs containing geological heterogeneity, hydraulic barriers and baffles. The validation of the design by field data in a Case Study will also be presented. It is shown that using FCDs in the wellbores helps to improve conformance and performance of SAGD well pairs significantly.
Challenges in PCP Smart Wells Application in a Heavy Oil Field
Authors: Toelsie S.. , Mohan A.. , Griffith C. R. , Wong Fong Sang M.. , Chin A Lien H.. 
Published: September 2014

Abstract
As of February 2014, Staatsolie operates 1560 active wells mainly with Progressive Cavity Pumps (PCP) for artificial lifting of heavy crude oil of averagely 16°API. These pumps are installed at an average depth of 1000 feet, producing crude from unconsolidated Tertiary sand reservoirs. Average pump life time of 2 months up to 25 years have been realized with these PCP's. Optimal operation of these PCP's requires sufficient submergence in liquid to prevent the pump running dry and causing early failures. To achieve maximum pump life time, a minimum wellbore annulus liquid level between 50 to 100 feet above pump intake is applied to avoid partial cavity filling problems and dry running of the PCP.
The liquid levels in the wells are mainly acoustically surveyed. Significant challenges in well optimizations to achieve optimal well production conditions at the lowest submergence level were experienced with a foamy liquid column in the annuli resulting into apparent high flowing bottomhole pressure (FBHP). The application of downhole pressure gauges started in 2005 with the main objective to increase the reliability of actual FBHP based on downhole memory and surface read out pressure sensors. Main disadvantage of the memory sensors was the required well intervention jobs to retrieve the gauge to download the recorded data, while surface read out downhole pressure sensors had the advantage of real-time data availability. With the development in downhole pressure sensor applications, smart well operation was initiated in 2011. A smart well at Staatsolie operates around a preset target fluid level. This is achieved by automatic regulation of the pump speed via a variable frequency drive. Smart monitoring can be done locally as well as remotely through an online interface option. Both monitoring methods have the possibility of automatic shutdown control once enabled. The smart application focused mainly on the effective control of the PCP speed to prevent downhole pump failures caused by running dry of the pump and the possibility in achieving optimized production.
This paper intends to cover the experienced operational challenges, advantages and disadvantages based on the testing of different smart well technologies in the Staatsolie heavy oil fields.
Autonomous Inflow Control Valve for Heavy and Extra-Heavy Oil
Authors: Aakre Haavard , Halvorsen Britt , Werswick Bjørnar , Mathiesen Vidar 
Published: September 2014

AbstractOne of the challenges in heavy and extra heavy oil production are the relatively low recovery rate. A major challenge is to improve recovery from existing fields by developing and implementing new technologies that make mature and marginal fields more profitable. One of the challenges in heavy oil field with water drive or gas cap is the mobility ratio. Due to the high viscosity water and/or gas breakthrough will occur after short time production. This means that after a period of production, all wells will have water and/or gas breakthrough. As the breakthrough expands the production have to be limited due to excessive gas and/or water production. This means that production from the well have to be choked or stopped, even there is oil left along the wellbore. Inflow Control Device (ICD) and Autonomous Inflow Control Device (AICD) has shown that the oil production and recovery can be increased significantly with better inflow control along the well. However, neither ICD nor AICD is able to shut off the unwanted gas and water production completely. The newly developed and patented Autonomous Inflow Control Valve (AICV®) can shut off the unwanted fluid completely. This is the next generation autonomous inflow control. The technology can be installed in both new horizontal wells and recompleted into old wells with high water productions. The new completion technology is presented and experimental test results with gas, oil and water are presented together with reservoir simulations that confirm that the AICV® will give significantly increased recovery in field suffering from gas or water breakthrough.
Evaluation of Different Strategies for Selective Steam Injection in Stratified Heavy-Oil Reservoirs
Authors: Hoyos Perdomo R.. , Ardila Cubillos L. J. , Munoz Navarro S. F. , Rincon Canas M. M. , Palma-Bustamante J. M. , Naranjo Suarez C. E. 
Published: September 2014

Abstract
Steam injection is one of most successful techniques for improving oil recovery in heavy oil fields. However some reservoirs have characteristics that are not adequate for the implementation of this technique due to reservoir heterogeneity, where steam driving is present in most favorable areas as a result giving a channeling which does not allow the existence of a uniform vertical steam distribution, leaving unheated areas, decreasing the process efficiency and obtaining unexpected oil recovery factors.
Therefore in this paper different strategies were evaluated using a numerical reservoir simulator to determine most suitable option with the greatest chance of technical success for the implementation of selective steam injection. For the development of this research initially a study of selective steam injection process was performed in stratified reservoirs, once it was made this, the strategies for selective injection were raised: Steam injection at maximum and minimum rates for different layers, the product of each layer permeability by thickness and reservoir stimulation preceded by selective injection. Finally, the strategies selected were implemented in conceptual simulation models built in this case for a stratified homogeneous and heterogeneous reservoir developed with the properties of a Colombian heavy oil field using a comercial software.
The final results were analyzed based on the behavior of the oil recovery factor and the injection profile, these confirmed the efficiency of the technique, allowing to heat the formations by appropriate injection rate and for this reason an increase in the amount of recovered oil.
After obtaining the simulation results is set the better or best possibilities for implementing selective injection, it determines the range of application where selective steam injection could be run efficiently obtained from the ratio of the product of the permeability by the thickness and it is determined that treatment is best for the reservoir with cyclic steam simulation before selective steam injection.
Zeroing of state variables in fractional descriptor electrical circuits by state-feedbacks
Authors: Kaczorek Tadeusz 
Published: September 2014

Abstract
The problem of zeroing of the state variables in fractional descriptor electrical circuits by state-feedbacks is formulated and solved. Necessary and sufficient conditions for the existence of gain matrices such that the state variables of closed-loop systems are zero for time greater zero are established. The procedure of choice of the gain matrices is demonstrated on simple descriptor electrical circuits with regular pencils