bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fiber Optic Distributed Temperature Sensing as an Alternative Interpreted Intelligent Completions.
Authors: Minggu Nur'ain , Kamarulzaman Ammar , Riyanto Latief , Ting Chang Siong , Kamat Dahlila , Ho Dylan Zhe , Zamdy Siti Nurdyana , P. Mosar Nur Faizah , Kalidas Sanggeetha , Tan Chee Seong 
Published: November 2020

Abstract
This study aims to validate and track valve positions for all the zones applying recorded distributed temperature sensing (DTS) data interpretation to propose the best combination of downhole inflow control valve (ICV) openings to optimize Well X-2 multizone commingled production. Fiber DTS is relied on as an innovation against downhole conditions that has compromised the three out of four downhole dual-gauges and valve position sensors.
For zonal water control purpose, ICV cycling and positioning have been attempted in 2019. The valve position tracking derived from the compromised downhole dual gauges and valve position sensors does not tally with the surface flow indication overall. Consequently, the original measurement intention of the fiber DTS as back-up zonal-rate calculation profiling and as potential sub-layer flow-contribution indicators is brought in as contingency zonal valve-opening tracking and guide that proved valuable for subsequent production optimization.
Downloaded DTS data is depth matched and validated against known operating conditions like time of each cycling stage and surface well test parameters (i.e. Liquid Rate, Watercut, Tubing Head Pressure (THP), Total Gas, Gas-Oil Ratio (GOR)), etc. To establish a baseline, several DTS traces of historical operating condition during a known stable period were selected, i.e. stable flowing condition at only Zone 4stable shut-in condition at surface with only ICV Zone 4 is opened
Downhole valve-position tracking can be interpreted alternatively from induced fiber temperature activities across the valve depth with a good temperature baseline benchmarking from DTS temperature profiling. In one of these alternative interpretations based on fiber temperature, it is found and validated that Zone 1 ICV is Closed, Zone 2, 3 and 4 are in opened position and continuously producing at any cycles. This is in conflict of zonal production control understanding initially based on the compromised downhole sensor indicating that all the zonal valves are supposedly in fully closed position.
In this case-study, DTS data has been proven useful and as an innovative alternative to determine downhole valve opening with analogue to flow contribution derivation methodology. Therefore, anytime in the future where Well X-2 valves cycling is planned to be carried out, there is a corresponding operating procedure that needs to incorporate onsite real-time DTS data monitoring to validate tracked valves positioning.
Installation of Annulus Cement Plugs Using Perforation, Wash and Cement Technique, a Lookback from a First for Australia
Authors: Bothamley Ryan , Haigh Mike , Soudi Mehdi 
Published: November 2020

Abstract
The Gorgon Foundation Project (GFP) development comprises of the Gorgon and Jansz-Io gas fields located in offshore Western Australia. To maintain gas supply, the Gorgon Stage 2 (GS2) project will expand the existing infrastructure with additional subsea production wells. The Gorgon Stage 2 (GS2) well architecture is designed to deliver a 7 5/8 in. tubing × 7 in. production liner Cased Hole Orientated Perforation completion (CHOP).
An unsuccessful production liner primary cement job resulted in an area of uncemented wellbore -casing annulus and a sand containing mobile water exposed. This led to the unresolvable uncertainty of water crossflow into adjacent produced sands. Under the current flow assurance restrictions, the risk of produced water could reduce production rates or require the well to be shut-in. To mitigate water flow potential, cement plug annulus impediments (baffles) were installed. The objective of these plugs are for reservoir management, not abandonment barrier plugs. This allowed an optimized scope for verification and contingency operations planned and executed.
This paper provides an insight into the collaborative efforts made by the Subsurface, Drilling and Completions (Wells) teams and Service Partners to plan and successfully execute two (2) Perforate, Wash and Cement plug jobs. Operations include the use of Tubing Conveyed Perforations (TCP) and Closed Loop Cup Type Wash and Cement tool, a first for Chevron in Australia. The cement plugs were deployed from a semi-submersible in ~220 m of water and placed at depths of ~5,700 mMD and ~5,500 mMD respectively, at inclinations of 60° and in high static bottom hole temperatures up to ~157°C.
The key challenges and lesson are discussed including planning to optimize swab cup integrity in high temperature operations.
Application of Computational Fluid Dynamics for Parametric Optimization of Jet-Type P/W/C Technique
Authors: Phadke Amal , Hovda Lars , Gonuguntla Praveen , Mueller Dan 
Published: November 2020

Abstract
Perforate-Wash-Cement (P/W/C) is a well plugging technique extensively used by ConocoPhillips in the Greater Ekofisk Area over the last ten years. In Jet-type P/W/C, Tubing Conveyed Perforating (TCP) guns perforate casing in the target interval before the zone is washed and a cross-sectional cement plug is installed using a specialized Bottom Hole Assembly (BHA). The goal is to maximize the cement plug quality through optimizing the BHA and operational process parameters within constraints imposed by the operating conditions. This paper describes application of Computational Fluid Dynamics (CFD) to achieve this objective. CFD is well suited for modeling wash and cement processes including the associated non-Newtonian fluids. A CFD model of these processes employs unsteady multiphase Reynolds Averaged Navier Stokes (RANS) based Volume of Fluid (VOF) approach with a Shear Stress Transport (SST) K-omega turbulence model. BHA translation and rotation are simulated using moving deforming-layering mesh with interface approach. Physical properties of non-Newtonian fluids selected are based on in-situ conditions and derived via lab tests. CFD-specific considerations such as domain size, turbulence model, mesh type and size, and computational timestep are discussed in this paper. The magnitude and duration of the jet-induced "pressure pulse" in the annular space between the formation wall and the casing are a key to efficient displacement during the wash and cementing processes. Displacement efficiency, in terms of the percentage of mud or cement in a control volume as a function of time, depends on perforation size and density, nozzle size/number, flow rate, fluid properties, as the ROP/BHA pulling speed and tool RPM. Key findings from a parametric study to optimize these parameters are presented. To validate CFD nozzle flow predictions and to rule out potential for false results due to cavitation, laboratory tests were performed under pressurized conditions. A comparison of results from CFD simulations using traditional versus optimized parameters are presented, demonstrating significant efficiency improvement achieved. The study initially focused on North Sea application. Encouraged by substantial improvement in process efficiency through parametric optimization, the technique was extended to UK operations and is planned for the Bayu-Undan field. Cementing simulation results for Bayu-Undan specific well configurations are presented, showing how CFD modeling helped reveal less than ideal cementing efficiency. Ultimately, this work provides significant time savings and quality improvement for P&A projects while maintaining a high safety standard.
Bridging the Gap Between Reservoir and Sample; Reducing Asset Development Risk by using Down-Hole Mercury Trapping and Non-Reactive Sampler for Trace Component Sampling
Authors: Dybdahl Bjorn , Lie Siv , Langford Michael , Thowsen Oddfinn 
Published: November 2020

Abstract
Accurate mercury and hydrogen sulphide measurements are essential for facilities design. Existing sampling methods are flawed in that they are not guaranteed to preserve the full quantity of reactive trace components present in a hydrocarbon sample. Subsequent incomplete measurements can have significant cost and HSE impact.
A novel down-hole sample capture and preservation of reactive components system is presented, enabling quicker, definitive identification of risks to plant integrity, worker and environmental exposures and sales value.
A selection of materials and coatings were tested for their inertness in relation to both mercury and hydrogen sulphide, in a variety of fluids (gas, oil, water and multiphase). All materials also had to be suitable for use in anticipated down-hole conditions.
The available literature was reviewed, and a mercury capturing system was designed and tested in a variety of fluids.
Once materials and designs had been selected, prototypes were tested using both certified calibration materials and samples spiked with known amounts of mercury.
The selected material and coating combination, when constructed in a chamber free from lubricants, O-rings and pistons, was shown to result in minimal sulphur component loss over an extended period, and to sufficiently delay the loss of mercury to allow it to be captured at reservoir concentrations.
Hydrogen sulphide concentrations were maintained in the tools for an extended period of time, allowing for the retrieval to surface of bottom-hole samplers, resulting in surface concentrations representative of those down-hole.
Mercury was successfully captured at down-hole conditions, preventing the impact of temperature and pressure changes at surface. Once at surface the mercury can be quantified without any losses associated with traditional sample handling.
Earlier identification of the presence of these species, along with accurate quantification, will aid facility design, such as whether removal facilities are required to meet sales specifications, and prevent harm to workers and the environment through unconsidered emissions of toxic components during production.
This paper presents a data collection process enhancing the quality of information essential for field development and maintenance planning and introduces a novel sampling approach that is capable of capturing representative down-hole samples for trace analysis of mercury and sulphur species, without losses experienced using existing techniques. The tool can be used within traditional sampling systems.
Optimising the Placement of Acid Treatments for Damage Removal and Well Stimulation
Authors: Mokogwu Ike , Wilson Sam , Stalker Robert , Graham Gordon 
Published: November 2020

Abstract
The requirement for appropriate placement in matrix acidizing to achieve efficient, effective stimulation or removal of formation damage has long been recognized. Despite this, assessing the effectiveness of an acid treatment in terms of placement and treatment efficiency prior to field deployment remains a challenge.
This paper presents a scenario where carefully designed core flood tests have been deployed alongside the use of a near-wellbore simulator to model and predict acid stimulation using viscosified fluids for treatments in a range of scenarios. Dual linear core flood tests were conducted to assess placement and clean-up efficacy of a viscosified acid treatment.
The efficiency of the treatment was then modelled using a state-of-the-art computer simulator. The computer simulator used is one which has been used extensively to model and optimize scale-inhibitor squeeze treatments in long-reach/complex wells. Its capability was extended to evaluate effects of fluid viscosification (staged or otherwise) on stimulation treatments.
Cases where partial/localised clean-up of a damaged zone was achieved, resulting in uneven stimulation were also examined. Results obtained from the model were validated with dual-linear core flood tests using simulated damaged and non-damaged zones. Resulting laboratory injection/diversion was compared to model predictions.
Core flood tests highlighted the importance of laboratory simulation of viscosified treatments. These tests showed how improved placement can be achieved by careful fluid design using viscosity alterations. The model was used to demonstrate the benefit (or otherwise) of different degrees of viscosification on evenness of treatment placement for systems with permeability contrasts, pressure differentials, presence of a water-producing zone, and various degrees and depths of skin per zone (including consideration of the effects on placement of acid reactivity on this damage).
Results showed that often even modest viscosification of the treatment fluid (~20 cP) improved placement. The greater the fraction that was viscosified (for staged treatments), the more even the placement. Viscosification invariably improved placement where a difference in native permeability existed (as opposed to a difference due to damage) and in most cases reduced the fraction of treatment fluid entering a water-producing zone.
What Does a Carbon Price do to Your Reserves and Development Plans?
Authors: Wong Daniel Lorng , Solomon Phillip , Jenvey Nigel 
Published: November 2020

Abstract
The paper presents a risk management tool that assesses the impact that potential future carbon taxes will have on a company's hydrocarbon Reserves base and associated cashflows. Based on a number of case studies, this paper will present a practical application of the open-source engineering-based model called Oil Production Greenhouse Gas Emissions Estimator (OPGEE), developed by Stanford University. The paper will demonstrate the application of the OPGEE model in the assessment of a range of carbon taxes, how they may vary the economic limit of a field's Reserves, and how this may influence a company's future field development decisions. This tool becomes useful in the risk management of the portfolio planning and capital allocation process where carbon tax risk can be objectively assessed and tested. If utilised correctly, the model can help to future-proof a company's hydrocarbon assets in an increasingly carbon constrained world. Asset owners or potential asset acquirers can assess the materiality of potential carbon tax impositions on assets and can prepare and adjust portfolios accordingly on an informed basis.
Application of Machine Learning for Fatigue Prediction of Flexible Risers - Digital Twin Approach
Authors: Repalle Nitin , Thethi Ricky , Viana Pedro , Tellier Elizabeth 
Published: November 2020

Abstract
Flexible pipes have a range of potential failure modes, however fatigue damage of the tensile, and eventually, the pressure armour, is one of the most common problems affecting the longevity of service life and the OPEX due to the common need for flexible riser replacement. With increasing utilisation of flexible pipe for current and future field developments, compounded by the recurrent need for field life extension, it is essential to monitor the riser fatigue regularly to maintain integrity, maximise asset life and to allow for informed appraisal before extending its operational life.
This paper presents a novel method of using the refined finite element analysis (FEA) in combination with Artificial Neural Network (ANN) to develop a riser digital twin that can be utilised as an operational decision-making tool for integrity management and life extension. A digital twin model is trained on a subset of available metocean and vessel motion data utilising advanced neural networks which can then be utilised to predict fatigue under the full spectrum of metocean and internal pressure conditions. This approach allows for a significant reduction in the estimation time of the fatigue damage compared to conventional FEA as well as improved accuracy of prediction.
The methodology presented in the paper has been primarily developed with the view of deepwater riser applications but is easily adaptable to shallow water application in combination with various floating vessels. A case study is presented to demonstrate how this technology is being deployed offshore. A comparison of FEA and digital twin approach is also presented to highlight the speed and efficiency of digital twin model whereby real-time insights on fatigue life can be evaluated for informed operational decisions.
Novel MYO15A Variants are Associated with Hearing Loss in the Two Iranian Pedigrees
Authors: Khatami Somayeh , Askari Masomeh , Bahreini Fatemeh , Chaleshtori Morteza Hashemzadeh , Hematian Saeed , Asgharzade Samira 
Published: November 2020

Abstract
Background: Clinical genetic diagnosis of non-syndromic hearing loss (NSHL) is quite challenging. With regard to its high heterogeneity as well as large size of some genes, it is also really difficult to detect causative mutations using traditional approaches. One of the recent technologies called whole-exome sequencing (WES) has been thus developed in this domain to remove the limitations of conventional methods.Methods: This study was a report on a research study of two unrelated pedigrees with multiple affected cases of hearing loss (HL). Accordingly, clinical evaluations and genetic analysis were performed in both families.Results: The results of WES data analysis to uncover autosomal recessive non-syndromic hearing loss (ARNSHL) disease-causing variants was reported in the present study. Initial analysis identified two novel variants of MYO15A i.e. c.T6442A:p.W2148R and c.10504dupT:p.C3502Lfs*15 correspondingly which were later confirmed by Sanger validations and segregation analyses. According to online prediction tools, both identified variants seemed to have damaging effects.Conclusion: In this study, whole exome sequencing were used as a first approach strategy to identify the two novel variants in MYO15A in two Iranian families with ARNSHL.
Benefit of dosimetry distribution for patients with multiple brain metastases from non-small cell lung cancer by Cyberknife Stereotactic radiosurgery (SRS) system
Authors: YU Xuyao , Wang Yuwen , Yuan Zhiyong , Yu Hui , Song Yongchun , Zhao Lujun , Wang Ping 
Published: November 2020

Abstract
Background: In order to obtain a high dose conformal index of tumor and steep dose fall-off in healthy tissues for brain metastasis stereotactic radiosurgery (SRS), the aim of this study was to investigate SRS planning optimization by comparing one multiple-lesions plan (MLP) with multiple single-lesion plans (SLPs) for patients with multiple brain metastases using the Cyberknife (CK) system.Methods: Fifty non-small cell lung cancer (NSCLC) patients (28 males and 22 females) with 2-4 brain metastases, inter-tumour distances less than 3 cm, were retrospectively replanned with the original prescription dose (12-32 Gy) in the original fractions (1-3). Two different clinical CK SRS plans (SLPs and MLP) were generated for the same patients with the same collimator and prescription isodose line (62-68%) by the CK Multiplan System. Both SLPs and MLP were able to achieve >95% PTV volume covered prescription dose and met the Timmerman 2011 organs at risk (brainstem, optic nerve and pituitary) constraints.Results: Compared with those in the SLPs, the maximum dose (Dmax) and mean dose (Dmean) of brainstem in the MLP were reduced 0.22-3.13% (2.62%) and 2.71-12.56% (5.57%), respectively, all P<0.05. Meanwhile, the volumes of the whole brain minus the tumors that received a single dose equivalent of 8-16 Gy (V8Gy-V16Gy) were effectively reduced in the MLP. The treatment time parameters, the total number of beams and monitor units, of the MLP were reduced by 3.31% and 1.47% (P<0.05), respectively. Although there were a few differences in the conformity index (CI) and homogeneity index (HI) between the two treatment plans, the differences were not statistically significant (P = 2.94 and 1.08>0.05).Conclusion: One multiple-lesions plan for brain metastases could achieve higher precision in the target and lower doses in healthy tissue while shortening the treatment time and improving the treatment efficiency over multiple single-lesion plans.
Socializing One Health: An Innovative Strategy to Investigate Social and Behavioral Risks of Emerging Viral Threats
Authors: Saylors Karen , Wolking David J. , Hagan Emily , Martinez Stephanie , Francisco Leilani , Euren Jason , Olson Sarah H. , Miller Maureen , Daszak Peter , Kreuder-Johnson Christine , Mazet Jonna A.K. 
Published: November 2020

Abstract
In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT program funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security.