bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hierarchical scales of soft-sediment deformation in erg deposits, Lower Jurassic Navajo Sandstone, Moab area, Utah, U.S.A.
Authors: Chan Marjorie A. , Hasiotis Stephen T. , Parrish Judith Totman 
Published: October 2020

ABSTRACTExtensive soft-sediment deformation (SSD) of multiple expressions and scales record active and dynamic events and processes in erg deposits of the Lower Jurassic Navajo Sandstone near Moab, Utah. The erg deposits preserve depositional environments of eolian dune, interdune, fluvial, playa, lake, and spring. A large range of SSD features, from intact beds showing little deformation to pervasively disturbed beds, exist in many of these deposits. A simplified classification index captures the different scales of SSD in ascending order of deformation intensity: 1) mostly intact bedding with small-scale wavy or undulatory deformation structures within single beds; 2) dish and flame structures; 3) meter-scale, kinked, slumped, rolled, overturned, vertical, and detached contorted crossbedding, and associated centimeter- to meter-scale pipes; and 4) disruptive diapirs and laterally extensive massive sandstone. The SSD features of deformed crossbed sets, diapirs, and massive sandstone beds, are consistently juxtaposed, and are thus genetically linked.Although the Navajo Sandstone has been considered a classic example of an extensive dry eolian system, both individual and combinations of strata bounded SSD features exemplify dynamic deformation, liquefaction, and fluidization that took place at various times after deposition. The lowest degree of deformation, SSD 1, is largely attributed to autogenic––inherent to the eolian system––or local allogenic processes. Larger degrees of deformation, SSD 2–4, were more likely produced by allogenic, external-forcing processes from regional changes in climate and/or near-surface groundwater conditions originating from the Uncompahgre uplift, with the deformation triggered by some event(s). Possible significant ground motion could have led to large-scale disruption in the Navajo sand sea across kilometer-scale intervals. The Navajo example establishes valuable hierarchical relationships of processes and products for recognizing and interpreting SSD in other ancient and modern eolian systems. This has particular relevance to sedimentary discoveries on Mars, where SSD features are visible from remote sensing imagery and rover exploration.
Attic Oil Recovery in the Alvheim Field
Authors: Langaas Kåre , Urazovskaya Oxana , Gueze Nicolas , Jeurissen Emile 
Published: October 2020

Abstract
The Boa and Kameleon accumulations in the Alvheim field have thin oil rims developed with long horizontal wells. Several of the latest wells are characterized as attic infill wells, drilled in the remaining oil rim, close to the gas cap, and shallower than the early wells. Autonomous inflow control technology is a key enabler for these wells. This paper describes the design, execution and performance review of a Boa attic well.
This well combined passive and autonomous inflow control devices (AICD). The AICDs used were tested with Alvheim fluid in the laboratory. A clear lower completion strategy was essential in the planning and execution of this well, e.g. to use AICD close to the gas cap and to design inflow linked to estimated oil per drainage area. 4D seismic interpretation, pilot wells information and deep resistivity logging while drilling were other critical factors to plan and optimize the well path. Tracers were mounted in the sand screens to monitor clean-up, inflow per zone and the onset of water production. The steady state inflow model was used extensively in the execution and review phases.
Pilot wells information and logging while drilling enabled successful geo-steering. During the drilling phase, the steady-state model was updated with the as-drilled information and the lower completion design adjusted to get what was estimated to be an optimal inflow. Tracers sampled during the clean-up indicated good clean-up of the entire well. The initial well performance with no water and low free gas amounts gave a larger pressure drop than expected. A later tracer based chemical PLT gave also slightly different results than expected. Pressure data, tracer data, log data and the effective multi-phase AICD model were thoroughly investigated to derive scenarios, that could explain this discrepancy. The most likely scenario gives a good history match for both pressure and tracers and gives extra insight into key reservoir parameters, zonal inflow and the effective behavior of the AICDs during multi-phase flow.
The well has exceeded pre-drill production rate expectations, despite the larger than expected pressure drop. This is partly explained by the autonomous choking on gas inflow along the wellbore. The post-review evaluation enables continuous improvements for Alvheim and similar fields.
A Structured Approach of Reliability Demonstration Test in the Development of Electromechanical Remotely Operated Downhole Control Device for Increased Operations Efficiency
Authors: Chakkungal Joseph , Christie Michael John , Shrivastava Pankaj 
Published: October 2020

Abstract
The remotely operated electromechanical control device (ECD) is coupled to an open-close valve that would normally require hydraulic lines from surface. With each function of the valve, an intervention is eliminated, which increases operational efficiency and saves rig time. As these devices are permanently installed in severe downhole environments, design-in reliability is paramount. Reliability demonstration test (RDT) is a key element of the design-for-reliability process to verify that the product satisfies the system reliability target. This paper presents a structured RDT approach to demonstrate the reliability of a remotely operated ECD in a cost- and time-efficient manner.
The reliability target of the ECD was established based on the tasks requirements (open-close functions), well conditions, and mission life. Key subassemblies of the ECD were identified, and a system reliability target was allocated to the subsystem level using a weight factor-based approach. A test-to-success methodology was used to design the RDT of individual subassemblies by identifying the underlying failure mechanism, applicable test stresses, and acceleration factors. A parametric cumulative binomial test design model was used to optimize the test parameters, such as sample size, test time, and number of valve open-close functions.
Conducting a system reliability test is often cost prohibitive. Therefore, performing a reliability test at the subsystem level is an alternative approach of verifying system reliability. Reliability allocation weight factors are determined based on the cost, time, and relative difficulty in testing the design feature. Aging parameters were found to be the number of valve open-close functions based on the underlying tasks, operating time, and well environment (temperature).
This paper highlights the structured methodology and application requirements of RDT to meet the mission reliability target of a remotely operated ECD. A comprehensive reliability target was established based on the underlying tasks, operating time, and well environment. A combination of overstress (temperature) and use-rate accelerations was used in the test design. An optimum value assessment of test design parameters was performed for developing a cost-effective test design. The approach and benefits of structured reliability test design are discussed in the paper.
High-Frequency, Azimuthal, Sonic LWD Tool Helps to Improve Compressional Velocity Processing in Formations with Harsh Logging Conditions: Case Study
Authors: Narayan Acharya Mihira , Al-Mershed Abdul Mohsen , Abdulkarim Anar 
Published: October 2020

Abstract
The oil and gas industry drills wells in harsher conditions year after year. Besides drilling challenges, these harsh conditions make it difficult to obtain accurate and consistent petrophysical measurements, particularly sonic and density data, because of high temperature, high pressure, and high mud weight (MW) in highly deviated wells.
Such conditions, in particular the high MW, attenuate sonic waves significantly, affecting the detection of sonic arrivals as well as ultrasonic caliper measurements. In addition, extremely high MW affects density data and invalidates photoelectric effect (Pe) measurements because of the high barite content. The Pe is typically used as an input to volumetric lithology interpretations in a four-mineral model. When the Pe is unreliable, sonic velocities can be applied to the interpretation workflow instead, if they are accurate. This paper discusses engineering solutions for software and hardware challenges and operational and technical aspects of acquiring the sonic log in combination with conventional triple-combo data.
As a result of the introduction of a high-frequency sonic logging-while-drilling (LWD) tool and advanced processing techniques, signal coherence tripled from an initial 0.3 (30%) to almost 0.9 (90%), significantly improving the quality of the data. Additionally, ultrasonic caliper coverage quadrupled from 25 to 100% of the logging interval, compared to previous runs in offset wells.
Furthermore, acoustic velocities play an important role as an input to geomechanical models, which study the stress regime and allow for estimation of rock moduli. Thus, an azimuthal acoustic tool measuring velocities 360° around the borehole provides information on formation stress anisotropy. Estimating formation rock moduli requires accurate density and acoustic properties provided by high- frequency sonic measurements.
For wells with inclination greater than 60°, it becomes difficult to run wireline logging. Therefore, LWD quad combo with a high-frequency, azimuthal acoustic tool is a viable solution for this environment. Additionally, it is advantageous that formation-evaluation measurements can be acquired while in drilling mode, saving rig time and reducing well-construction costs.
Driving Operations Efficiency Through Right Skilling and Remote Operations
Authors: Khan Awes Ahmed , Hamre Irene Brekne , Nabili Asal 
Published: October 2020

Abstract
Operation Efficiency and reduced well cost has been the focus in the oil & gas industry since as long as the industry has existed. The parameters of measuring the efficiency and the KPIs have evolved overtime. Historically, KPIs have been in a single domain of either maximizing the ROP from the bit, drilling the section in a single trip, increasing hole stability with performance drilling fluids, moving rigs in record time within the HSE boundaries and extracting the last barrels from brown field developments. With initiatives in the industry, such as reducing the carbon footprint, decrease the POB on hardship locations and deploying technology to assist in conventional operations, the scope of operational efficiency has expanded beyond just a single domain.
The latest advancements in digitization and technology are making virtual presence a reality. This emerging capability aided in transforming conventional offshore day-to-day operations into a new model based on maximizing remote operations. Implementing these models successfully requires collaboration and change management from all stakeholders as it challenges the status quo of the historical oilfield careers. Additionally, it requires a comprehensive look into existing standard procedures, as well as calls for the appropriate risk mitigation measures to ensure safe transition to this new operational model.
This paper will discuss the role of technology in enabling this new operational model. It will provide a detailed skill mapping of offshore tasks to transfer to remote onshore centers as well as a comprehensive gap analysis to prescribe the required training to address those gaps. Finally, it will also present the milestones achieved in operational efficiency resulting from the implementation of the new model.
This paper will present in detail the Right Skilled operational roles that enable new operational model to be implemented in spirit and add the efficiencies in execution.
A Rapid, Simple, Portable Tool to Design and Analyse the Value of Inflow Control Devices ICD and Autonomous Inflow Control Devices AICD
Authors: Prakasa Bona , Corona Gina , Allen Clifford 
Published: October 2020

Abstract
The criticality and a means of modelling latest generation wells employing Inflow Control Device (ICD) and Autonomous Inflow Control Device (AICD) completions providing solutions to the production constraints encountered in multi-reservoir contact wells is presented in this paper. ICD-AICD wells enable a better-distributed production/injection from/into different reservoir zones/layers by adding a passive and or autonomous downhole restriction. ICD-AICD technology thereby enables more efficient field development by improving sweep efficiency, potentially reducing the number of production/injection wells required and maintaining well longevity and profitability.
Modelling the completion interaction with the reservoir is critical to determine the incremental value of applying such technology. This being achieved by coupling the wellbore model, which includes the lower completion, to the reservoir properties. The modelling technique, a grid-based numerical well/reservoir simulation, necessitates knowledgeable personnel and detailed, sometimes uncertain, geological data. The multiple model iterations required when using ICD-AICD technology further increases the reservoir simulators' computing time.
A new tool was developed to design and analyse ICD-AICD efficiency, bridging between a simple steady-state inflow snapshot evaluation and a full dynamic reservoir simulation. The new model uses the proven classical method of fractional flow, combined with the performance of specific flow control devices installed in the well. This allows fast forecasting of the production profile and oil recovery, as well as optimizing ICD-AICD configuration at the well design stage.
The proposed workflow is implemented as either a production forecast or a diagnostic tool for an ICD-AICD well in an immiscible gas or aquifer-supported oil field. It provides one missing link between today's ICD-AICD design workflows and the long-term value evaluation of a specific design when a full reservoir simulation is either not available or too time consuming. The method's transparency and ease of implementation of its algorithms can make it a useful tool for well and reservoir engineers to design and analyse the value of ICD-AICD devices.
Well Design Changes Extend Well Life in Subsiding Overburden at Valhall From 7 to 24 Years
Authors: Kristiansen Tron Golder 
Published: October 2020

Abstract
Normal casing design in the oil and gas industry is based on uniform pressure load cases, where the load cases are given by the pressure of various fluids and gases that can be encountered during various scenarios during the well life. In some cases, the exploitation for oil and gas can result in substantial changes in in-situ rock stress and resulting deformations in the subsurface that will result in other types of loads on the well structure. An overview of various well structure/tubular deformation modes experienced in the oil and gas industry is given by Dusseault, et al.,2001. There do also exist a substantial literature of tubular deformations in wells going through salt. A summary of some of these cases is given by Willson et. al, 2003.
The Valhall case, from the Norwegian Continental Shelf (NCS) discussed here in this paper, is one type of reservoirs where casing and liners have been deformed. The Valhall type of reservoirs are the ones with large amounts of reservoir compaction that result in large enough deformation in the overlaying overburden to deform casing and liners. Typical reservoirs experiencing this are chalk, diatomite and HPHT reservoirs, but also others with large depletion, weak reservoir rocks, very thick reservoirs or a combination of these attributes. The documentation of the Valhall case is therefore applicable to many reservoirs in the industry.
This paper documents the Valhall case from the first observations of deformations in the overburden, including cases with production of overburden shale and clay through damaged tubulars. We also present the most important parts of the work that was performed to understand the mechanisms causing the deformations. Then we present the well design changes that one selected to implement, like steel grades, thickness/diameter (t/D)-ratio and concentric cemented liner laps. Some of this was covered in Kristiansen et al., 2000. We also present a prioritized list of design options in terms of their impact on well life. We also look at how the results of these design changes is estimated to have increased the average well life at Valhall from 7 to more than 24 years around 20 years after the changes to the well design had been implemented.
Perception Of Oral Hygiene Practices And Dental Treatment Permissible During Fasting Amongst Dental Patients: A Cross-Sectional Study In Pakistan
Authors: Tariq Khaloud , Hassan Arooj Ul , Hassan Muhammad , Din Shahab Ud , Arooj Zunaira , Baig Moghees A. 
Published: October 2020

Abstract
Background:
Fasting places prohibitions on eating and drinking for a certain period of time. Although many dental treatments have been said to be safe and can be performed while fasting, other may result in breaking of fast. The study aims to evaluate the perception of dental patients of Lahore, Pakistan regarding effect of such treatments and hygiene measures during fasting.

Methods :
It was a cross-sectional survey carried out in 2 dental teaching hospitals of Lahore, Pakistan from September- October 2018. Patients were asked to complete a self-administered structured questionnaire developed to assess the knowledge regarding dental treatments, and hygiene practices while fasting. The questionnaire consisted of 7 items regarding the influence of dental treatments such as filling, scaling, and extraction etc. on fasting. Questions were also added regarding maintenance of oral hygiene such as brushing and its effect on fast. Frequencies and percentages are used to display results. Chi-squared test was used for statistical analysis to estimate difference between gender, and educational status with perception of procedures breaking fast.

Results :
Out of 415 responses, 374 were included for analysis. About 76.2% respondents believed that undergoing extraction broke fast. Scaling was thought to nullify the fast by 45.5% of respondents. 52.9% perceived root canal treatment to break fast along with 67.6%, who believed anaesthesia administration broke fast. As far as oral hygiene was concerned, brushing was reported to break fast by 57.5% with the use of mouthwash invalidating fast by 63.4%.
Conclusion :
The respondents were generally aware of some procedures not breaking fast however, most thought that administration of anaesthesia, undergoing root canal treatment, and extraction invalidated fast. Also, hygiene maintenance measures such as brushing and use of mouthwash during was also thought to break fast. It is imperative that the healthcare providers should be familiar with the effect of dental treatments and oral hygiene measures on fasting state that can influence the treatment plan of the patients.
CatBoost for Big Data: an Interdisciplinary Review
Authors: Hancock John , Khoshgoftaar Taghi M 
Published: October 2020

Abstract
Gradient Boosted Decision Trees (GBDT’s) are a powerful tool for classiﬁcation and regression tasks in Big Data. Researchers should be familiar with the strengths and weaknesses of current implementations of GBDT’s in order to use them eﬀectively and make successful contributions. CatBoost is a member of the family of GBDT machine learning ensemble techniques. Since its debut in late 2018, researchers have successfully used CatBoost for machine learning studies involving Big Data. We take this opportunity to review recent research on CatBoost as it relates to Big Data, and learn best practices from studies that cast CatBoost in a positive light, as well as studies where CatBoost does not outshine other techniques, since we can learn lessons from both types of scenarios. Furthermore, as a Decision Tree based algorithm, CatBoost is well-suited to machine learning tasks involving categorical, heterogeneous data. Recent work across multiple disciplines illustrates CatBoost’s eﬀectiveness and shortcomings in classiﬁcation and regression tasks. Another important issue we expose in literature on CatBoost is its sensitivity to hyper-parameters and the importance of hyper-parameter tuning. One contribution we make is to take an interdisciplinary approach to cover studies related to CatBoost in a single work. This provides researchers an in-depth understanding to help clarify proper application of CatBoost in solving problems. To the best of our knowledge, this is the ﬁrst survey that studies all works related to CatBoost in a single publication.
Knockdown of RNF6 Inhibits Cervical Cancer HeLa Cells Growth by Suppressing the MAPK/ERK Signaling
Authors: Zhu Kang , Bai He , Mu Mingzhu , Xue Yuanyuan , Duan Zhao 
Published: October 2020

Abstract
Background

Given its crucial role in human malignancies, how Ring finger protein 6 (RNF6) functions in cervical cancer has yet to be elucidated. In our research, we explored the biological significance of RNF6 in cervical cancer HeLa cells and its possible regulatory mechanism.
Methods

The expression levels of RNF6 mRNA and protein in cervical cancer tissues and cells were both analyzed, the former by Gene Expression Profiling Interactive Analysis (GEPIA), and the latter by quantitative real-time PCR (qRT-PCR) and immunohistochemistry assays. In vitro cell proliferation was tested through MTT assay and flow cytometer was used to detected Cell apoptosis. The activation of ERK(extracellular signal regulated kinase) was explored by Western Blot.
Results

In the present research, we found that the expression of RNF6 was high in both primary tissues and cervical cancer cells. RNF6 could promote cervical cancer HeLa cells growth. Once knockdown of RNF6 in cervical cancer cells, cell proliferation could be suppressed and cell apoptosis was promoted. Moreover, its elevation had an adverse effect on the prognosis of cervical cancer. Further studies showed that ERK activation is one of the potential mechanisms.
Conclusion

These findings provided evidence that the up-regulated RNF6 could activate the MAPK/ERK pathway to regulate the cell growth in cervical cancer, which suggested that RNF6 could be a promising target for diagnosis and treatment for cervical cancer.