bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Low Motion FPSO Design Hosting SCR and TTR in Harsh Environment
Authors: Mansour Alaa , Wu Chunfa , Peng Cheng , Zuccolo Ricardo , Bagaria Ashish , Bhat Shankar , Yu Jim , Sung Hong Gun 
Published: April 2017

Abstract
In the development of remote offshore oil and gas fields with minimal or no infra-structure, the Floating Production Storage and Offloading (FPSO) unit is the preferred solution. The FPSO has the advantage of providing the required storage in the hull and direct offloading to tankers of opportunity. Steel Catenary Risers (SCRs) are the preferred solution in wet-tree applications due to their simplicity, robustness and low Capital cost (CAPEX) and Operational cost (OPEX) compared to other riser options. Also, Top Tensioned Risers (TTRs) have their well-known advantages in allowing direct vertical access to production wells and hence enhanced recovery. However, due to its relatively high dynamic motion, conventional FPSO is not a feasible host for TTRs or SCRs in most environments.
In this paper, a Low Motion FPSO (LM-FPSO) design with the ability to host SCRs and TTRs is presented and evaluated for applications in deepwater field developments. A case study is prepared to compare the technical and commercial aspects of a field development in 250m water depth using a conventional FPSO to those using a wet-tree LM-FPSO supporting SCRs and a dry-tree LM-FPSO hosting TTRs. The constructability, transportability and installability of the new design along with its performance verification through physical scale model testing are discussed and presented in this paper.
Subsea All-Electric
Authors: Abicht Daniel , Halvorsen Glenn-Roar , Ramberg Rune Mode 
Published: April 2017

Abstract
The trend in subsea development is heading towards simplification, industrialization, digitalization and commercial optimization in an environment of longer step-out and deep / ultra-deep water applications. With that the limitation of existing electro hydraulic systems as exposed. Statoil has launched an All-Electric Subsea (AES) initiative to prove the feasibility of new flexible, cost efficient subsea production system (SPS) to meet future demands. While most of the main technology elements are available and proven in use, full market and operator acceptance seems to be a challenge. However, in the current and future situation and with the experience gained from the Åsgard subsea compression system, all electric is considered as a feasible future option for SPS.
The strategy for the AES initiate is to identify all electric concepts with SPS vendors in order to establish cost effective solutions and strive for standardization of products and interfaces. The AES initiative aims to have system approach and examine the impact on all elements of a subsea development, i.e. covering topside, umbilical, SPS and downhole etc. This will ensure the benefit of an all-electric implementation is presented. The intention is to present the advantages seen with an all-electric for all aspects, i.e. with respect to cost, project execution, operational flexibility, standardization.
This paper will present the current status of the AES initiative covering: –the fundamental features of the AES technology and concepts–the potential of this technology for operation in production control systems–status of the all-electric initiative with respect to technology maturity–the activities required to close the identified technical gaps–the implementation of all electric SPS solutions
Use of Surfactant in Cement Slurry to Mitigate Incompatibility with Synthetic-Based Drilling Fluids
Authors: Pereira R. , Cardozo J. , Bogaerts M. , McNulty J. , Lehr J. , Santos L. 
Published: April 2017

Abstract
In deepwater Gulf of Mexico, the use of synthetic-based drilling fluids (SBM) is common practice in all types of wells drilled by different operators. These fluids have been under constant development in past years. However, even with the latest in SBM technology, cementing operations can be adversely affected when this type of fluid is used, which can compromise the quality of the cement jobs.
One of the challenges faced is the rheological incompatibility between the cement slurry and the SBM. This may lead to issues such as induced losses during primary cementing operations, due to higher friction pressures, or stuck pipe during plug placement, among others. The higher friction pressures during cement placement in primary jobs can also lead to an inaccurate or inconclusive post-job evaluation when attempting to match software-simulated pressures with actual pressures acquired during the jobs.
Despite the use of mechanical separation and spacers, the post-job analysis of several recent cement jobs suggests that contact between cement slurry and drilling fluid is often still occurring. As expected, this contact is most frequently occurring in the annular space wherein there is typically an absence of mechanical separation. In these jobs, laboratory test results using mixtures of slurry and SBM with various ratios have shown levels of incompatibility, which have been correlated to evidence of higher-than-expected friction pressures in the same jobs.
The solution proposed for this scenario is to add surfactant or surfactant-based chemical additives at low concentrations to the cement slurry. The addition of surfactant to cement slurries has been proven to reduce rheological incompatibility between the slurry and SBM and the impact of contamination on set cement properties.
This paper presents the laboratory test results, operational concerns, mitigation, and a case study showing the application and effectiveness of this technique comparing similar strings that were cemented in different wells.
Case Histories: Improved Hydraulic Fracturing Design in a Constrained Oil Price Environment
Authors: Johnson Matthew 
Published: April 2017

Abstract
In this paper, we have demonstrated how frac fluid design has changed since the downturn beginning in 2014. We have standardized proppant per stimulated foot and have provided production metrics on the aggregate level for the various fluid design systems. We will give an overview of the U.S. onshore and three case studies of the Eagle Ford, Midland Basin and Delaware Basin.
Managed Pressure Cementing in HPHT Utilizing Real Time Pressure Estimation and Control Software – A Case Study
Authors: Rostami S. Ameen , Mirrajabi M. , Stoian E. , Babar K. 
Published: April 2017

Abstract
MPD enables drillers to navigate through narrow drilling windows to reach designed target depths. After a hole section is drilled, pressure management is still required to pull drill strings out and run and cement liners. Conventional cementing programs and procedures may not be practical for a challenging hole section that has been drilled by MPD. Elaborate wellbore pressure management is required to ensure safe and efficient cementing operations. The same closed loop circulation system utilized for drilling is used to manage the wellbore pressure during cement operations. The technique of pressure management during liner cement jobs was utilized repeatedly by a major client in one of the most challenging HPHT campaigns in the North Sea. This paper provides an insight into the technique as well as information on the procedures, challenges and lessons learned pertinent to these operations. Various cases studies describing the setup, planning and execution of operations, simulation vs measured data will be compared.
Drilling wells in complex environments with century-old technology is difficult at best and unsafe at worst. From drilling through narrow pore-pressure/fracture-pressure gradient windows to mitigating kicks and differential sticking, managed pressure drilling (MPD) succeeds when conventional techniques are likely to fail. MPD entails the use of specialized equipment to control wellbore pressure profiles more precisely than is possible with conventional drilling methods. MPD enables drillers to navigate through narrow drilling windows to reach designed target depths. After a hole section is drilled, pressure management is still required to pull drill strings out and run and cement liners. Conventional cementing programs and procedures may not be practical for a challenging hole section that has been drilled by MPD. Elaborate wellbore pressure management is required to ensure safe and efficient cementing operations. The same closed loop circulation system utilized for drilling is used to manage the wellbore pressure during cement operations. A case study describing the setup, planning and execution of operations, and simulation is presented in this paper.
Project Cost Reduction and De-Risking with Large-AUVs for Hydrographic and Pipeline Surveys
Authors: Ricketts Leonard , Ordonez Christopher 
Published: April 2017

Abstract
AUVs first entered the Oil and Gas market in the 1990s due to a requirement to solve challenges posed by deep water survey. In particular, ROV tether management systems were highlighted as a major technical hurdle. Nowadays, demand for AUV surveys is being fuelled by commercial and quality demands. The data quality and resolution that AUVs deliver are seen as the major contributing factors in de-risking projects, starting from the FEED stage.
AUV technology has developed to such a degree that since October 2012, DOF Subsea reliability figures of over 320 dives yielding +25000km of survey, delivered less than 4% downtime on 8 different vessels for 6 different clients and these figures are not isolated. Other AUV service providers can claim similar successes, testament to the major strides forward the AUV industry has made since the 1990s.
Evaluation of Flowloop Uncertainty with Live Hydrocarbon Process Fluids for Multiphase Flowmeters Validation
Authors: Amin A. , Harsono E. , Kamies E. , Heyen G. , Vos G. De 
Published: April 2017

Abstract
The validation of multiphase flowmeters (MPFMs) in a controlled flowloop using live hydrocarbon fluid is examined with emphasis on the impact of measured and modelled fluid properties uncertainty on the loop reference measurements.
A customized process model based on data reconciliation with integrated thermodynamics package is built to evaluate the loop reference flowrates and their uncertainties at the multiphase flowmeter test station conditions. The process model accounts for data redundancy and physical constraints to ensure consistency of the reconciled measured and unmeasured variables used in the validation of multiphase flowmeters.
The model is applied to a generic set of test points performed in a high pressure (HP) flowloop. The paper discusses the modeling and operational aspects involved in validating the subsea meter's measured flowrates. It also highlights the sensitivity of different inputs and their uncertainties on MPFM performance evaluation.
For the first time, the proposed approach enables operators to achieve the reality of subsea operations inside a highly controlled flowloop environment without resorting to overly simplified assumptions and practices. The approach is further validated by applying it to a high-pressure, high-volume, true multiphase flowloop using actual hydrocarbon fluids.
High Voltage Subsea Pump – A Low Cost Subsea Boosting Enabler
Authors: Margarida A. , Pimentel J. , Thibaut E. , Cardoso E. 
Published: April 2017

In a cost constrained scenario, technology driven solutions aiming at CAPEX reductions are crucial to make Subsea Processing (SSP) projects economically attractive. Subsea Processing encompasses three main fields: (i) Subsea Gas or Liquid Separation, (ii) Subsea Compression and (iii) Subsea Boosting - Multiphase or Water. Despite the fact that Boosting is a SSP discipline in itself, both Separation and Compression will also rely on subsea pumps to support the process.
Although subsea boosting technology is available and has been successfully deployed in several projects, high cost of system infrastructure is still a barrier for a broader technology adoption. Typically, a high boost subsea pumping system will require both topside and subsea infrastructure. Topsides, at the floating production unit, a subsea pump will require electric power, a variable frequency drive (VFD) to control motor speed, and a hydraulic power unit (HPU) to supply subsea barrier fluid to the motor (except for ESPs). Subsea, a pump module, power connections and a high voltage umbilical are necessary pieces of equipment without which the pump cannot be powered or installed. Aiming to reduce subsea umbilical cross-section and consequently overall system cost, operators have collaborated to develop a high(er) voltage subsea motor. Currently, existing subsea motors are powered with voltages ranging from 4.16 kV to 6.6 kV. For umbilical power dissipation, higher voltage yields a square-law reduction effect. Since ampacity (amount of electric current a conductor can carry) is a function of to the amount of copper, lower amps translate into less copper. The program scope comprises the design, components qualification and prototype build of a permanent magnet subsea motor to operate at 13.6 kV. Beta prototype design and ratings were based on a existing 3.2 MW Permanent Magnet Motor (PMM).
Integrity, Monitoring, Inspection, and Maintenance of FPSO Turret Mooring Systems
Authors: Duggal Arun , Izadparast Amir , Minnebo Joerik 
Published: April 2017

Abstract
The long-term in-service performance of turret mooring systems is becoming increasingly important given the exponential increase in the number and complexity of FPSO facilities worldwide. The trend of floating production systems being developed in deeper waters and harsher environments coupled with longer service life requirements make the knowledge and understanding of long-term performance, monitoring, inspection, and maintenance even more important.
The paper discusses the key aspects of the long-term integrity of FPSO turret mooring systems, focusing on inspection, monitoring and maintenance of critical components of the mooring system, i.e., the anchor leg, bearing, and swivel systems. The paper provides recommendations on practical methods of monitoring and inspection of these critical components and highlights the importance of training of the operation team to ensure the recommendations are followed.
Liquefaction Technologies and Mechanical Drive Considerations for Floating LNG
Authors: Tierling Shane , Attaway Doug 
Published: April 2017

Abstract
Floating LNG (FLNG) technologies are being deployed to monetize mid-sized offshore gas reservoirs, avoiding constructing a sub-sea gas pipeline to a land based LNG facility and export jetty. A previous OTC-Brasil paper (OTC-26158 Gas Pretreatment Considerations for Floating LNG) has discussed the pre-treatment options available for FLNG and this paper is a continuation discussing the liquefaction and mechanical drive options. The discussion will be broken down to offshore safety and economic considerations, the liquefaction technologies available and the mechanical drive technologies available.
Offshore liquefaction technologies are often novel and many lack offshore references. The available offshore liquefaction technologies and Licensors will be presented. Because of the diversity of liquefaction technologies, the technologies will be grouped by process configuration, and then these groupings of technologies will be compared with an emphasis on safety, economics, scale and weight. Application of mechanical drives for centrifugal compressors in an offshore environment is well-practiced. Given this maturity, types of technologies will be compared on power ratings, availability, flexibility and weight, without reference to individual suppliers.
The reader will come away with an understanding of the trade-offs involved in technology selection of liquefaction and mechanical drives.
Advances in GIS-Based 3-D Predictive Geotechnical Soil Model Tools
Authors: Bruce Brittany A. , Campbell Kerry J. , Dean Cornelia 
Published: April 2017

AbstractThis paper describes and illustrates recent advances in and current functionality of geographical information system (GIS)-based marine geotechnical (typically soil) model tools that are being used to predict geotechnical conditions throughout a specified 3-D space. Marine soil models are developed by integrating seismic survey and geotechnical data and then using GIS technology to efficiently manage, analyze, extract, and display predicted soil conditions. The tools described here provide geotechnical engineers, designers, and other end users with a quick and convenient way to predict general soil stratigraphy and properties at any selected location down to the depth of the model (locations are not constrained to geophysical survey lines).Specifically, a suite of customized soil model tools have been developed to provide a rapid and innovative approach to extracting, summarizing, and exporting geotechnical soils information from GIS-based 3-D soil models. Collectively, the soil model tools are referred to as the Virtual Soil Boring (VSB) tools. The VSB tools are conveniently packaged and launched from a custom toolbar installed as an add-in to a GIS map application. The VSB tools provide the user with an instantaneous means of determining geotechnical variability among user-selected locations, and provides an efficient way of exporting this information for use in complementary analyses. The VSB tools represent a major technical and efficiency advancement over the traditional "maps and 2-D profiles" method still being used by some. Importantly, the VSB tools are very user friendly and users do not have to be GIS specialists. In short, the VSB tools allow better decisions about site selection and foundation design to be made faster by end users.The GIS-based VSB tools described here are one of the most recent contributions to integrated site characterization methods that have been evolving for several decades. The VSB tools are but one aspect of the accelerating trend to provide comprehensive 3-D functionality to predictive ground (or earth) models of stratigraphy, geotechnical/earth materials, and geologic conditions. Robust 3-D predictive ground models are essential for providing reliable and comprehensive characterization and assessment of soil conditions and geohazards as a basis for optimum site selection and efficient foundation design for offshore structures.
Driving for Competitive and Affordable Projects in the Gulf of Mexico
Authors: Pledge David De , Pereiras Andrew , Bryson Bill , Orlean Robert 
Published: April 2017

Abstract
Deepwater developments CAN be affordable in low price environments! One key is to view designs through a new lens as we create our development concepts. This paper describes how Shell un-shackled the talents of the industry's engineering and construction communities to create very viable, low cost development systems for potential Gulf of Mexico prospects. The paper speaks to the ways that corporate orthodoxies were challenged to enable these solutions, engaging Shell's technical experts creatively to define new solutions. The results of our findings were both surprising and compelling. Most importantly, there continues to be space for new, low cost deep water developments.
This paper presents an alternative approach to the design and execution of low cost deep water development systems that are demonstrably affordable in a low price environment.
The paper describes how Shell un-shackled the talents of the industry's engineering and construction communities to create very viable, low cost development systems for potential Gulf of Mexico prospects. It speaks to the ways that corporate orthodoxies were challenged to enable these solutions, engaging Shell's technical experts creatively to define new solutions. The approach used was simultaneously rigorous and un-fettered.
Shell's efforts began by defining bare-bones surface and subsea facilities that included only minimal systems and sparing, and smaller compliments of Operations personnel. Shell relied heavily on input from the contractor community to define these initial, minimum systems. During the subsequent review of these facilities designs, Shell asked of all internal stakeholder a series of key questions designed to make visible incremental costs and functionalities of additional systems above the proposed minimums. This bottoms-up approach resulted in the selection of only high value-added functionalities that mitigate business risk, while making transparent the decision processes that lead to them. The final designs represented very workable, operable and maintainable systems that reduced capital cost by between 15 and 25%, based solely on scope reductions.
As a result of this approach, Shell has reset the baseline from which they will develop future prospects. We conclude from this approach that deep water developments can be affordable in low price environments. One key is to view designs through a new lens as we create our development concepts. Most importantly, there continues to be space for new, low cost deep water developments into the future.
Lower Limb and Trunk Biomechanics After Fatigue in Competitive Female Irish Dancers
Authors: Wild Catherine Y. , Grealish Avril , Hopper Diana 
Published: April 2017

Context: Because of the increasing popularity of participation in Irish dance, the incidence of lower limb injuries is high among this competitive population.Objective: To investigate the effects of fatigue on the peak lower limb and trunk angles as well as the peak lower limb joint forces and moments of competitive female Irish dancers during the performance of a dance-specific single-limb landing.Design: Cross-sectional study.Setting: Laboratory.Patients or Other Participants: Fourteen healthy, female, competitive Irish dancers (age = 19.4 ± 3.7 years, height = 165.3 ± 5.9 cm, mass = 57.9 ± 8.2 kg).Intervention(s): Participants performed an Irish dance–specific leap before and after a dance-specific fatigue protocol. During each landing movement, 3-dimensional lower limb kinematics (250 Hz) and ground reaction forces (1000 Hz) were collected. Paired t tests were performed to determine the differences (P ≤ .05) in lower limb and trunk biomechanics prefatigue and postfatigue.Main Outcome Measure(s): Peak lower limb and trunk angles as well as peak lower limb joint reaction forces and external moments.Results: Compared with the prefatigue trials, dancers landed with reduced ankle plantar flexion (P = .003) and hip external rotation (P = .007) and increased hip-adduction alignment (P = .034) postfatigue. Dancers displayed greater anterior shear (P = .003) and compressive (P = .024) forces at the ankle and greater external knee-flexion moments (P = .024) during the postfatigue compared with the prefatigue landing trials.Conclusions: When fatigued, dancers displayed a decline in landing performance in terms of aesthetics as well as increased ankle- and knee-joint loading, potentially exposing them to a greater risk of injuries.
An investigation of virgin variation of branching pattern of ECA and CCA: a case report
Authors: Rajani S. 
Published: April 2017

Abstract
Introduction: Common carotid and its two major branches, external and internal carotid arteries form arterial network for blood supply in the head and neck region. Variations in configuration and branching pattern of these arteries change the irrigation pattern and complicate the identification of specific arteries during surgical intervention coupled with imagery interpretation for diagnosis. Though handful variations have been documented yet there is strong need to report unusual, new and virgin organization of configuration and branching pattern in these arteries. Case Report: During dissection of head and neck region, anomalous branching pattern consisting of bilateral trifitrcation/quadrification of common and external carotid arteries and abnormal trifitrcation of distal external carotid artery was observed. Conclusion: Lack of knowledge of these variants in branching coniguration may lead to unfortunate differential diagnosis and iatrogenic complications.