bluuebunny/crossref_metadata_2025_split huggingface dataset:
Monitoring of Under-Reamer Function Status to Confirm In-Gauge Hole, Technology Validated by Open Hole Calliper: Case Study
Authors: Huggett Tom , Hunter Craig , Alahmad Mohammad , Eatough Oliver 
Published: February 2019

Abstract
Challenging conditions in a HP/HT well in the UK Central North Sea, led to the deployment of a contingent expandable liner. Under-reaming tools were needed to facilitate running of the contingent liner. Under-reaming operations are associated with a degree of uncertainty on the final hole diameter. A technology was deployed to monitor cutter position, wear and vibrations. With the aim of removing the above uncertainty. An open-hole calliper run was performed to validate the technology.
The monitoring system utilizes an arrangement of sensors to measure variables that are critical to under-reaming operations. The sensors are housed within the expandable cutting structure of the under-reamer and comprises of a cutter block position indicator and a PDC cutting structure wear sensor. The monitoring system can also record downhole dynamics at the under-reamer. The system can therefore determine, via memory data, the actual under-reamer extension size at any point during the run, therefore allowing the minimum hole diameter to be derived. Providing immediate feedback at the rig site once the tool is at surface.
The first run globally of the 12 ¼" × 14" size is presented, the monitoring system recorded 187 hrs of data. The cutter blocks position sensor showed the cutting structure was fully expanded as required whilst pumping at drilling flow rate once the tool was activated. The wear sensors were fully active and showed no wear for the duration of the systems battery life. A combination of the positional and wear sensors indicated full gauge hole to the recorded depth. Due to the type of contingent liner the delivery of gauge hole was critical. As such, the data was validated using a dedicated open-hole calliper run on wireline. The calliper confirmed the open-hole diameter calculated based on data provided by the wear and position sensors. Based on this result the requirement for an open-hole calliper run can be reconsidered. In addition, the acceleration recorded was well correlated with the MWD recorded vibration data and allowed parameter recommendations to be generated.
The ability to monitor the position and status of the under-reamer cutting structure eliminates uncertainty on the final hole size following under-reaming operations and identifies any problem areas and their probable causes prior to running casing/liner. In turn this has the potential to eliminate the need for wireline runs and therefore reduce the open-hole time in a potentially unstable formation.
Overcoming Challenges in an HP/HT Abandonment in the North Sea
Authors: Rublevskyi Anton , Reid James , Joneja Galen , Nafikova Svetlana , Salazar Jose 
Published: February 2019

Abstract
With the increase in decommissioning/abandonment work in the North Sea, a major operator had the objective to permanently abandon a well that had been temporarily suspended. There were several key challenges associated with this project: high pore pressure and temperature, a completion packer set in a target abandonment interval, and small cement plug volumes. These obstacles had to be overcome to complete the abandonment safely and efficiently. The primary barrier to the deepest potential flow zone, zone 1, was established by running flush slimline tubing through the 5-in. tubing and 9 7/8-in. production packer. The cement plug was then successfully placed below, across, and above the production packer. The cement plug was successfully tagged and inflow tested, creating a primary barrier against zone 1. This approach eliminated the need to remove the production packer prior to the abandonment plug being set, which saved the operator approximately 10 days of rig time. This paper outlines the detailed design preparations and presents the case history where these steps were implemented successfully.
A Paradigm in Rotary Steerable Drilling - Market Demands Drive a New Solution
Authors: Clegg John , Mejia Camilo , Farley Steve 
Published: February 2019

Abstract
This paper reviews how the Rotary Steerable System (RSS) market has changed over the last two decades. It explores current market forces; specifically the shift in RSS philosophy resulting from ever-improving motor steerable technology. It describes how the need for longer laterals with minimal tortuosity, maximum drilling efficiency, reduced risk of unplanned events, and elimination of AFE overspend, along with the paradigm shift in the directional drilling market seen since 2014, drove the specification for a new-generation RSS tool. The paper describes the development of a new RSS with a topology and control concept that allows full proportional control of bias from a fully rotating, push-the-bit tool, with the ability to "turn off" any bias during operations where side force is undesirable and to minimize potential tortuosity. It describes how the design team focused on modular design and rapid turn around of tools, in order to maximize utilization and efficiency. Field-test results are included, which demonstrate build and turn at up to 10°/100 ft. and the ability to drill accurate lateral sections. Field results also include the use of ultrasonic imaging while drilling to investigate hole quality.
Validation of Directional Survey Data Against Positional Uncertainty Models
Authors: Willerth Marc , Maus Stefan 
Published: February 2019

Abstract
Positional uncertainty is a critical component of managing collision risk while drilling. Ensuring that survey data meet the requirements of their uncertainty models has historically required complicated analysis. Most consumers of survey data are not experts and knowing when escalation is required in a high-risk situation can be unclear. This problem will increase as more data is evaluated by automated decision-making systems. Two novel methods are proposed to analyze sets of survey data against uncertainty models with the intent to answer the questions: "Is it safe to continue drilling" and "Does this wellbore need to be resurveyed?".
The proposed methods evaluate a survey set using the error sources, error magnitudes, and error propagations contained in positional uncertainty models. A quality control error covariance matrix is constructed, and the set is evaluated against it. Two statistical outputs are generated: a statistical distance that explains how well an additional survey fits with the existing survey data, and an overall survey assessment that describes the likelihood of an error-model compliant system producing the observed dataset.
The methods are used to evaluate downhole magnetic survey data that was flagged after evaluation by subject matter experts, but traditional quality control measures had failed to identify as problematic. Errors that do not fit the expectations of the error model are flagged in a way that is apparent to a non-expert user and can be integrated into an automated alert system. How to include these procedures in drilling workflows is discussed, including when escalation to a subject matter expert is required.
A system is proposed where, with minor modification to existing error models, this analysis can be automated for wellbore surveys of all kinds. Additional discussion is included on how these methods will fit into the upcoming API recommended practice on wellbore surveying.
Using Big Data to Study the Impact of Wellbore Tortuosity on Drilling, Completions, and Production Performance
Authors: Baumgartner Theresa , Lin Chris , Liu Yu , Mendonsa Aaron , Zimpfer Douglas 
Published: February 2019

Abstract
The principal indicators for drilling performance have traditionally been measures of time. For instance, time vs. depth and ROP serve as instant KPIs that are easy to measure and have obvious implications. Other potential performance parameters, such as the quality of the constructed wellbore are not considered in the drilling process. A standardized wellbore quality index has not been established yet. This work aims to narrow the gap between drilling and subsequent completion, production and plug & abandonment operations.
The operator gathered large data sets to link wellbore tortuosity with non-productive time (NPT) in drilling and completion and production outcome. A previously published measure of wellbore geometry, tortuosity index developed at the University of Texas (Zhou et al., 2016), was adjusted to better fit the requirements for the tortuosity study presented in this paper. Tortuosity values for horizontal, curve and vertical sections are calculated from about 2400 publicly available directional surveys for a basin in the US. The study uses data from hundreds of these wells to reveal correlations of tortuosity with drilling and completion NPT and correlations with production values in one out of three reservoir layers analyzed in this work.
Change Management Challenges Deploying a Rig-Based Drilling Advisory System
Authors: Behounek Michael , Millican Blake , Nelson Brian , Wicks Matthew , Rintala Eugene , White Matthew , Thetford Taylor , Ashok Pradeepkumar , Ramos Dawson 
Published: February 2019

Abstract
Sophisticated drilling analysis software is available to provide drillers with advice on setting and modifying drilling parameters such as WOB, RPM, etc., but getting a driller to accept the recommendations of the software is still complicated. Additionally, it is not sufficient that a driller on one test rig accept the changes to the drilling techniques and modified workflows. The challenge is to scale across an operator’s mixed rig contractor fleet getting fleet-wide driller and stakeholder buy-in.
The system used for this paper consists of a Rig-based Drilling Advisory System (RDAS) where new advisory information is displayed in the driller’s cabin running real-time pattern recognition algorithms to detect drilling dysfunctions. When a drilling dysfunction is encountered, a change in drilling parameters is suggested. Additionally, drilling parameters from offset wells are made automatically available for the driller’s use on the drilling screen. Through this process, we are entrusting the field personnel with a slightly higher level of technical responsibility. The team iteratively improved the system using feedback from drillers who used the RDAS.
Two rigs were selected for testing on how the drillers and the wellsite supervisors utilize the system. Feedback from these two rigs pointed to the need for customization on a well by well basis. Working through the on-site drilling engineers on the test rigs, modifications were then made to the system to fine tune how they wanted the drilling advisory to behave. For example, a wellsite supervisor wanted the system to ignore mild stick slip in a short drill section - a rigid system with no customization could not provide an adequate solution. Being adaptable helped to improve the acceptance, as the driller now started seeing the advisory more as a support tool. Agile software development was critical to success and the rig personnel appreciated the quick modifications to the system. This also gave them confidence in the process, and made them more responsive to change. Comparing drilling performance from wells before and after deployment provided a way to quantify the benefits. Seven total systems were deployed over a five month period. The operator continues to deploy to additional rigs until all active rigs are covered.
Change management is challenging. Many projects fail when this process is not properly executed. Presented here in detail is the process used by an operator to successfully implement a drilling advisory system across a mixed group of rig contractors. This process and the learnings presented in this paper serve as a case study for other companies embarking on such deployments.
Offline Cementing Technique
Authors: Urdaneta Javier , Wiriawan I Made , Barragan Gabriel , Curtis James , Casado Carlos , Schaefer Preston 
Published: February 2019

Abstract
The expansion phase of the offshore Mafumeira major capital project in Angola commenced in 2015. Because ofthe global low-oil-price environment, the team was challenged to revise the basis of design and operational procedures to help reduce well construction time by more than 50% and accelerate the date of first oil production.A major focus of this effort was to conduct as many offline activities as possible during the well construction.
Offline activities were performed before or after the jackup rig movedonto the slot, reducing the overall project cycle time. The feasibility of conducting offline cementing was evaluated and risk-assessed for several of the planned casing strings. The concept was conceived and implemented, initially for the 20-in. surface casings, for the second batch of wells in the expansion project. The ability to cement the surface casing offline allowed the rig to move to another slot and drill the next well in the batch campaign while simultaneously cementing, cutting the casing, and installing the wellhead on the previous well.
Nine tophole sections have been cemented in Angola using the offline cementing technique, providing USD 4 million intotal cost savings and reducing rig time approximately 18 hours per well, which helped achieve the overall target of reducing well construction time by 50%.The cementing objectives were successfully achieved in all cases, including adequate top of cement (TOC) and formation integrity tests (FITs) upon drilling out the shoes.
As part of continuous performance improvement, the opportunity to perform cementing offline in deeper hole sections of the well is being assessed.
Irreversible fatal contrast-induced encephalopathy: a case report
Authors: Zhao Wei , Zhang Jinping , Song Yun , Sun Lili , Zheng Meimei , Yin Hao , Zhang Jun , Wang Wei , Han Ju 
Published: February 2019

Abstract
Background: Contrast-induced encephalopathy (CIE) is a well-known complication of iodinated contrast agents during angiography and vascular interventions. It can manifest as hemiparesis, cortical blindness, speech changes, Parkinsonism, confusion, seizure, and coma. Most of the reported CIE cases have been transient and reversible. Irreversible fatal CIE cases have been rarely reported. All the fatal CIE cases reported involved the use of ionic high osmolar contrast agents. Here, we document a heretofore unreported fatal CIE after digital subtraction angiography（DSA）using iopamidol, which is a type of non-ionic monomer low osmolar contrast agent.
Case presentation: A 71-year-old woman was admitted to our Department of Neurology for paroxysmal buzzing of the brain. The cerebral magnetic resonance angiography (MRA) indicated the presence of arteriosclerosis of the cerebral arteries and bilateral stenosis of the middle cerebral arteries. The patient underwent DSA for further diagnostic work-up. The total amount of iopamidol used during the procedure was 110 ml. The patient experienced headache during the procedure, followed by dizziness with nausea and vomiting. Although the patient was treated with anti-oedema drugs, her deterioration was continuous. She gradually became comatose and suffered irreversible fatal cerebral oedema, which was confirmed by cerebral computed tomography (CT). Finally, the patient died 56 days after the procedure due to irreversible fatal cerebral oedema.
Conclusions: This report documents that iopamidol-induced encephalopathy may not always have a benign outcome and can result in irreversible fatal cerebral oedema.
When the pits fill up: (in)visible flows of waste in urban India
Authors: Prasad C. S. Sharada , Ray Isha 
Published: February 2019

Abstract
India's flagship program on sanitation and hygiene – the Swachh Bharat Mission – aims to eliminate open defecation and to manage urban waste for a ‘Clean India’. The emptying of toilet pits and the transport of waste are as critical as more toilets are for sustainable sanitation. In unsewered cities of the global South, these services are mainly provided by privately run cleaning trucks. We find that the physical and social mechanisms through which these services are organized are virtually invisible in national fecal sludge and waste management policies. Based on a rich ethnography of cleaning trucks in Bangalore, India, we show that trucking operations dispose of sludge in ways that harm both public health and the environment, and that the caste composition of sanitation work helps to keep it invisible from officials and the public. We draw on the concept of the social role of disgust to explain the seen-and-unseen nature of these trucks. ‘Seeing’ sludge management as it is practiced is essential for understanding how the sanitary city is being produced and for the success of future sanitation reforms.
This article has been made Open Access thanks to the generous support of a global network of libraries as part of the Knowledge Unlatched Select initiative.
Illuminating utility benchmarking data with analysis and consumer feedback – insights from Nepal
Authors: Ogata R. , Khatri N. , Sakamoto M. 
Published: February 2019

Abstract
The Government of Nepal, with the support of the Japan International Cooperation Agency (JICA), conducted a benchmarking activity with performance indicators, water quality tests, and a consumer survey for 26 larger and older town water supply services in the country. Performance indicators varied widely between the different towns: number of staff/1,000 connection (staff ratio), for example, ranged from 2.8 to 15.3, whereas water supply coverage ranged from 13.8% to 98.4%, and operating ratios which indicate financial performance ranged from 0.24 to 2.8. Critically poor biological water quality was found in water quality tests that 55% of tap water samples were Escherichia coli-contaminated. Overall, customer satisfaction ranged between 14% and 97%. Analysis showed that the operating ratio was significantly correlated with the staff ratio, the number of water supply connections, the water coverage, and the metered ratio. Results of water quality tests and the consumer survey revealed risk in direct drinking of tap water and a need to improve tap water quality by managing free residual chlorine and leakage reduction. Customers' satisfaction with water sufficiency was found to be significantly correlated with their perception of the reliability of supply time rather than the number of supply hours and water consumption rate.
This article has been made Open Access thanks to the generous support of a global network of libraries as part of the Knowledge Unlatched Select initiative.
Treatment of road runoff by coagulation/flocculation and sedimentation
Authors: Nyström F. , Nordqvist K. , Herrmann I. , Hedström A. , Viklander M. 
Published: February 2019

Abstract
A laboratory investigation of the treatment potential of a coagulation process in the context of stormwater treatment was undertaken. The initial 25 L road runoff generated from four rain events was collected and subjected to a jar-testing regime with two commercial coagulants. The treatment effect was assessed by analysing the runoff before and after treatment for turbidity, suspended solids and metal content. The coagulation process resulted in particle and total metal reduction of more than 90% compared to 40% for only sedimentation. Up to 40% reduction of dissolved Cr, Cu and Pb was also observed compared to 0% for sedimentation. This study shows that coagulation may be a useful process for stormwater treatment systems when the treatment requirements are high.
Ultrastructural Analysis of Human Gallstones using Synchrotron Radiation µCT
Authors: Chen Weixin , Liu Riming , Tao Suo , Shen Weixing , Zhou Weihong , Song Chao , Lu Huanhua , Xing Chungen 
Published: February 2019

Objective:
Gallstone formation is a pathological process of mineralization in the human
body. Determination of the morphology and ultrastructure of gallstones holds the key to
understanding the pathophysiology of gallbladder disease. Synchrotron radiation phase-contrast Xray
microtomography is a novel technology, which is designed for comprehensive analysis of
gallstone ultrastructure.

Materials and Methods:
Nine human gallstones were obtained from the Department of Pathology,
Qingpu branch of Zhongshan Hospital Affiliated to Fudan University (China), and scanned by
synchrotron radiation µCT (SR µCT). The imaging data generated by SR µCT scan were analyzed.

Results:
The three-dimensional ultrastructure of human gallstones corresponding to their
cholesterol and bile pigment composition was determined.

Conclusions:
The ultrastructure of gallstones exhibits considerable diversity and complexity. The
synchrotron radiation phase-contrast X-ray microtomography is a valuable tool for in-depth study
of human gallstones.
Discovery and Optimization of a Series of Sulfonamide Inverse Agonists for the Retinoic Acid Receptor-Related Orphan Receptor-α
Authors: Doebelin Christelle , He Yuanjun , Campbell Sean , Nuhant Philippe , Kumar Naresh , Koenig Marcel , Garcia-Ordonez Ruben , Chang Mi Ra , Roush William R. , Lin Li , Kahn Susan , Cameron Michael D. , Griffin Patrick R. , Solt Laura A. , Kamenecka Theodore M. 
Published: February 2019

Background:
Despite a massive industry endeavor to develop RORγ-modulators for
autoimmune disorders, there has been no indication of efforts to target the close family member
RORα for similar indications. This may be due to the misconception that RORα is redundant to
RORγ, or the inherent difficulty in cultivating tractable starting points for RORα. RORα-selective
modulators would be useful tools to interrogate the biology of this understudied orphan nuclear receptor.

Objectives:
he goal of this research effort was to identify and optimize synthetic ligands for RORα
starting from the known LXR agonist T0901317.

Methods:
Fourty-five analogs of the sulfonamide lead (1) were synthesized and evaluated for their
ability to suppress the transcriptional activity of RORα, RORγ, and LXRα in cell-based assays.
Analogs were characterized by 1H-NMR, 13C-NMR, and LC-MS analysis. The pharmacokinetic
profile of the most selective RORα inverse agonist was evaluated in rats with intraperitoneal (i.p.)
and per oral (p.o.)dosing.

Results:
Structure-activity relationship studies led to potent dual RORα/RORγ inverse agonists as
well as RORα-selective inverse agonists (20, 28). LXR activity could be reduced by removing the
sulfonamide nitrogen substituent. Attempts to improve the potency of these selective leads by
varying substitution patterns throughout the molecule proved challenging.

Conclusion:
The synthetic RORα-selective inverse agonists identified (20, 28) can be utilized as
chemical tools to probe the function of RORα in vitro and in vivo.