bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resolution of a Perennial Water-Cut History Match Challenge Helps to Optimize Drilling Program
Authors: Yusuf Nurudeen Oluwatosin , Andrew Parrish , Silpngarmlers Lynn 
Published: July 2019

Abstract
Reservoir_B7 is one of the top reservoirs in Adobe field and was considered for further development in a multi-year drilling campaign. The initial opportunity identification and new drill forecasts for this reservoir were done using an old simulation model. Over the years, the challenge with this model had been the prediction water production from existing producers which necessitated the introduction of local permeability barriers in the model. However, to validate this opportunity and ensure reliability of production forecasts, a new simulation study was commissioned.
A systematic approach was employed during the new study which involved continuous engagement between Earth Modeler and Simulation Engineer. This led to identification of a low-quality facies which had not been properly characterized. Recharacterization of these facies led to an improvement in history match with an overall good pressure and saturation matches on both well-by-well and reservoir levels. The latest history matched model was used to validate the proposed opportunity and indicated a sub-economic incremental recovery. This led to elimination of hitherto top opportunity from the drilling program and preventing a bad investment by the company.
Experimental Investigation of Nanoskin Formation Threshold for Nano-Enhanced Oil Recovery Nano-EOR
Authors: Omotosho Yetunde A. , Falode Olugbenga A. , Ojo Temilola I. 
Published: July 2019

Abstract
Enhanced Oil Recovery (EOR) methods continue to be dominant in improving world’s oil reserves as producing fields mature. Global growth of 18% was recorded in proved reserves between 2007 and 2017 (BP Statistical Review, 2018), with North America, which has invested in several EOR techniques, contributing about 14% to this growth. This proves that EOR stands as a long-term solution to the menace of dwindling reserves. Recently, nanotechnology has been gaining attention for application in the petroleum industry. It has been established that nanoparticles dispersed in base fluids such as water, brine or certain organic solvents (nanofluid) exhibit some special properties proved to be advantageous for EOR purposes. Additional recovery of about 30% has been recorded. However, permeability damage, which has been widely reported, is yet to be critically studied and analysed.
The objective of this research was to investigate how two important properties; concentration and injection rate of the nanofluid, affect oil recovery, and as well establish the thresholds of conditions which lead to permeability impairment and injection fluid loss during nanoflooding with silica nanoparticles. The permeability impairment layer which is gradually formed at the rock pore surface is termed nanoskin (a concept introduced by the author).
Four core samples were flooded with brine followed by silica nanofluid of four different concentrations viz; 0.01, 0.5, 2.0 amd 3.0% wt/wt respectively. The flooding process was accompanied with changing injection rates viz; 0.5, 1.0, 2.0, 3.0 cm3/min.
The result indicated that concentration of 2.0% wt/wt and injection rate of 2.0 cm3/min were threshold levels that guaranteed optimal oil recovery from the Niger Delta core samples. The overall result demonstrates that nanoflooding is a viable EOR technique and establishes a combination of parameters that will minimize nanoskin formation during nano-EOR process.
Using Deep Learning and Computer Vision Techniques to Improve Facility Corrosion Risk Management Systems 2.0
Authors: Ejimuda Chijioke , Ejimuda Chukwumaijem 
Published: July 2019

Abstract
During fit for service or corrosion risk assessments of oil and gas facility systems, a key parameter required to design and implement an effective risk management strategy is visual inspection. This paper explains how using state of the art computer vision and deep learning techniques could address such challenges. We used majorly the python programming language, Tensorflow Application Programming Interface, Resnet deep learning architecture, GPU machines and cloud computing technologies to achieve this. Beyond the challenges of obtaining sufficient corrosion defects data, our final solution is a systematic method that would assist field personnel, facility engineers, service companies and management more accurately detect corrosion defect types and failure modes unbiasedly. This leads to more cost effective and quicker recommendation of preventive or corrective measures.
Continuous Circulation Technology to Reduce Drilling Days in Offshore West Africa: Case Study
Authors: Johnson Rachel , Zerari Djamel , Salicante Piervittorio , Midolo Paolo 
Published: July 2019

Abstract
Continuous circulation technology is a form of managed pressure drilling (MPD) where the constant circulation of drilling fluid is maintained by allowing the rig pumps to remain on while adding and removing stands of drillpipe. Using continuous circulation, many drilling challenges are solved through continuous hole cleaning and solids transport, including maintaining constant bottomhole pressure (BHP), reducing the loading of solids and cuttings bed formation resulting from a pumps-off state, mitigating stuck pipe incidents, reducing ballooning effects, providing continuous cooling of bottomhole assembly (BHA) components, and improving formation integrity. Continuous circulation technology was used extensively for its hole-cleaning benefits during a 17-month development, gas drilling, and oil drilling campaign on a deepwater drillship in offshore West Africa from 2015-2016. Operations restarted in 2018 and are ongoing in 2019.
Deepwater drilling using continuous circulation in this field provided a solution for significantly helping improve the rate of penetration (ROP) through continuous hole cleaning when drilling one stand per hour or faster. With constant circulation during the drillpipe connection process, the operator was able to significantly decrease the amount of time spent on hole-cleaning activities after a stand was drilled down in both oil-based mud (OBM) and water-based mud (WBM) applications. The enhanced hole cleaning provided by continuous circulation also helped improve cuttings transport efficiency, mitigate stuck pipe incidents, and enhanced the ability to drill a clean hole.
This continuous circulation system was used on a deepwater drillship in offshore West Africa on 16 wells from 2015-2016, following two wells drilled without this technology, and four wells after the restart in 2018. Overall, more than 535 operating days and more than 1230 successful continuous circulation drillpipe connections were performed during both drilling and tripping operations. Because of the increased ROP provided by continuous hole cleaning with the system, approximately five drilling days were saved per well, totaling to an approximate 85 drilling day reduction over the planned drilling campaign from 2015-2016, resulting in a significant cost savings to the operator and to obtain first production much sooner than anticipated.
Continuous circulation technology has proven to reduce overall nonproductive time (NPT) and total drilling days. During a long-term drilling campaign, additional improvements were recognized with superior prewell planning and front-end engineering design to minimize interference with rig operations and equipment and improve understanding and communication between the service company and operator. A newer generation, dual-activity rig helped prevent downtime by providing a platform for continuous repair and maintenance activities while drilling.
Implication of Structural Analysis in the Development and Management of a Maturing Field – The Akpo Case Study
Authors: Nosike Livinus , Uwerikowe Gabriel , Biu Victor , Adeyemi Adeoye , Usman Musa 
Published: July 2019

Abstract
Regional studies are known to show major compartmentalization in an oil field, while observations during development and production often highlight local structural connectivity issues that require fault characterization at field-scale to mitigate uncertainty in reserve or stakes. The Akpo field, located in the deep offshore Niger Delta, exemplifies a maturing field where these structural connectivity issues are dominant and play significant roles in field development. Structural discrepancies in the crest and flanks of the anticline result in varying water contacts and overpressure differences, affecting connected volumes and sweep efficiency.
Qualitative fault throw analysis, aided by 4-D monitoring results, show that same faults may be sealing and communicating at difference areas, across reservoir fairways in the deep offshore turbiditic channel complexes, delineated as architectural elements. Shale Gouge Ratio (SGR) helps in further constraining the sealing/leaking impact of fault gouge at a log-scale, such that adjacent well data can be used quantitatively to assess preferential flow paths across and within faults zones. This revealed an along-fault, up-fault and across-fault connectivity anisotropy.
This work addresses how the fault characterization was used to assess the following: Reservoir compartmentalization, leading to panel separated as fault blocks.Communication across fault, shown by throw map and SGR.The varying water contacts, which tend to result from upwelling of fluid within panel.Sweep across panels, from injectors to producers.The well in real-time operational situation, where well trajectory traverses a fault.
The study resulted in an improved infill well planning and placement, targeting unswept hydrocarbon, where well trajectories were determined by knowledge of fault compartmentalization, initial static connectivity shown by virgin pressures and present dynamic communication across injector-producer pairs. Post-mortem analysis of these infill wells was helpful in understanding the dynamic role of the crestal-collapse faults offsetting the reservoirs in the Akpo anticline, leading to optimization and increased productivity.
Well Control: Hard or Soft Shut-In, The Onshore Experience
Authors: Ogunyemi Ephraim O. , Oghenewoakpo Supreme 
Published: July 2019

Abstract
This paper investigates the effect of pressure surge referred to as "water hammer" on the formation as a result of shut - in procedure. Two methods are generally used to shut – in the well when kick is experienced: a soft shut – in or a hard shut – in. It is generally believed that when a well is hard shut – in, the additional surge pressure is capable of fracturing the formation creating a big issue in well pressure control. Hence, most operators advise against the use of this procedure. Drill sim 50 was used to simulate various kick sizes ranging from 2bbls to 20bbls and the resultant pressure surge due to water hammer was calculated and added. The result obtained indicated that soft shut – in procedure allows additional influx that increases the pressure on the formation while hard shut – in reduces the additional influx thereby reduces the possibility of formation breakdown. For all the kick sizes considered, the BHP for hard shut – in with additional pressure surge due to water hammer effect was not up to formation fracture pressure of the various depths considered.
The paper concludes that more time will be saved to prevent additional influx if hard shut – in procedure is adopted especially in an onshore location of Niger Delta on which the simulation studies was carried out.
Lessons Learnt During Hydraulic Workover for ESP Replacement
Authors: Othman Mohammed , Ojanomare Choja 
Published: July 2019

Abstract
The Well A14 was drilled in 2004 with dual completion and flowed for about 7 years. The well was shut-in due to high water cut and sand production. In December 2011, the well was re-completed single with 7’’ Cased Hole Gravel Pack and ESP + YTool. The well was later sidetracked and deviated to a tie-in point in order to encounter the target at optimal structural positions and provide additional drainage points on the target level to optimize hydrocarbon recovery from the field. The flowed for a period of 2 ½ years and stopped flowing as a result of electric fault on the ESP. Following this and the unfavorable price of crude oil at the time, there was need for an optimized means of intervention; several factors were considered and a HWO intervention using HWPU was selected. This paper addresses the contingent challenges faced and how these were overcome in the course of this 2nd W/O to recover the existing completion and run-in with a new design of ESP and accessories. During POOH the old completion after laying down the D-ESP packer on surface, the well kicked as a result of poor circulation during the killing operation. This resulted in a loss of control and fluid influx spilling to the environment. This challenge was addressed in compliance with the best standards. The W/O was resumed and the entire completion string and ESP assembly + Ytool retrieved. Subsequently during the final installation of the new ESP, the string parted at the threaded connection and the entire ESP completion assembly was lost in hole. This second incident was carefully reviewed by the team involved prior mobilization of fishing equipment and eventual recovery of the lost-in-hole in a single attempt. The entire completion containing the lost-in- hole, on about 2000m of 3 ½" Tubing completion was recovered; the new assemblies were prepared and RIH successfully. The well was eventually completed and currently flowing (≈2000bopd). The responsible team reviewed the incidents, identified lapses and proposed future procedures in order to forestall reoccurrence.
Impact of Well Production Tubing Diameter on Multiphase Flow Regime Profile in Oredo Fields, Niger Delta, Nigeria
Authors: Dala Joshua , Akanji Lateef T. , Olalekan Olafuyi , Bello Kelani , Jadhawar Prashant 
Published: July 2019

Abstract
The impact of production tubing diameter on multiphase flow regime profile is investigated. For a given isolated section of the production tubing in selected wells drilled and completed in Oredo fields, velocity profile and fluid flow characteristics at the production tubing centreline and along the pipe wall were evaluated. Complex flow behaviour is characterised by tubing diameter and asymptotic flow pattern at the tubing surface where no-slip boundary condition was imposed. Future inflow production performance relationship (IPR) and influence on vertical lift performance are determinable from the multiphase flow regime profiles. Furthermore, we investigate the impact of production tubing diameter on multiphase flow regime profile in Oredo oil field Nigeria. Mechanisms responsible for complex fluid flow behaviour and transition in different tubing configuration with implication on production optimisation and performance analysis are also included in the model design and analysis. From the results obtained in this study, it is evident that higher volume of oil is producible from bigger production tubing. However, implications on vertical lift performance and production optimisation require a more critical analyses.
RESEARCH IN THE RETIREMENT VILLAGE COMMUNITY – DOES THE RECRUITED SAMPLE REFLECT THE RESIDENT POPULATION?
Authors: Connolly Martin Joseph , Hikaka Joanna , Bloomfield Katherine , Broad Joanna , Wu Zhenqiang , Boyd Michal , Peri Kathy , Calvert Cheryl , Tatton Annie , Higgins Ann-Marie , Bramley Dale 
Published: July 2019

Abstract
Background

Retirement Villages (RVs) for older people represent a burgeoning industry. However, we know little about residents’ demographics and health/disability issues - information which could inform health planning, facilitate independence and reduce service demand. RVs are semi-closed communities: access for researchers is most conveniently gained via RV managers. We are studying RV residents in Auckland, New Zealand (NZ) to acquire demographic, health, disability and social data, with a randomized-controlled-trial of a multidisciplinary intervention aimed to reduce adverse outcomes. We here describe recruitment problems we encountered.

Methods

We planned to approach all RVs in Auckland/Waitemata Districts, with random sampling of residents in each village using unit/apartment lists as the sampling frame. Exclusions: Refusal of/inability to consent (complying with NZ legislation; ACER<65, or person clinicians felt lacked capacity). We planned access via RV managers and contact residents by ‘letter-drop’ then ‘door-knocks’. In ‘small’ RVs (n<60 units), we planned to contact all residents, with random selection in ‘larger’ RVs.

Results

We approached managers of 53 of the 65 RVs. 38 initially replied positively, of which 34 permitted us to recruit residents, 6 did not reply. Another 9 declined our first approach, of which eight were ‘small’, seven independently-owned. Some managers prohibited ‘letter-drops’ or ‘door-knocks’ at all or without prior residents’ meetings to assess acceptance of this methodology. Hence, we had to recruit volunteers (in 23 villages) via residents’ meetings, posters/newsletters and word-of-mouth. We recruited 578 residents from 33 villages (one village had no volunteers) (median age=82yrs; 420 female; 217 sampled, 361 volunteers).

Conclusions

Due to organizational/managers’ policy, and the fact that NZ legislation did not allow recruitment of residents without legal capacity to consent, our sample does not fully represent our RV population. Future RV research should consider alternative recruitment strategies e.g. random sampling from national census, electoral roll, or via residents’ organizations.
Hematological Reference Ranges for Apparently Healthy Blood Donors in Debre Markos, North West Ethiopia, 2016
Authors: Birhan Mekuriaw Mesfin , Tadele Tigist , Haile Diresbachew , Demeke Dessalegn , Getahun Biruk , Assefa Sefialem 
Published: July 2019

Abstract
Objective

The aim of this study was to determine hematological reference ranges for apparently healthy blood donors in Debre Markos, North West Ethiopia.

Result

A total of 250 adults with the median age of 20 (range 18 to 48) years were recruited. The mean ± standard deviation of hematological values were white blood cells (WBC) count 6.34±1.82×103/µl (males) and 6.96±1.89×103/µl (females); absolute neutrophil count 3.57±1.47×103/µl (male) and 3.99±1.38×103/µl (females); absolute lymphocyte count, 2.09±0.64×103/µl (males) and 2.27±0.68×103/µl (females); absolute mid-sized cell count 0.68±0.36× 103/µl (males) and 0.70±0.37×103/µl (females); red blood cell (RBC) count 5.13±0.49×106/µL (males) and 4.57±0.36×106/µL (females) platelets, 255.86±65.96 × 103/µl (male) and 280.67±65.71× 103/µl (female).
Effects of electroacupuncture therapy for depression: study protocol for a multi-centered, randomized controlled trial
Authors: Cai Wa , Ma Wen , Chen Ai-Wen , Shen Wei-Dong 
Published: July 2019

Abstract
Background

As a major public health problem, depression has a negative impact on individuals and society. The aim of this well-designed trial is to evaluate the efficacy and safety of electroacupuncture (EA) treatment for depression.

Methods/Design

A three-arm parallel, non-blinded, randomized controlled trial was performed in four hospitals (centers). 144 participants will be divided into three groups: electroacupuncture (EA) group, hand acupuncture (HA) group and western medicine group. Participants in EA group and HA group received 12 sessions of acupuncture treatment for 4 weeks. Participants allocated to western medicine group will only take 20mg fluoxetine orally per day for 4 weeks. The primary outcome is Hamilton Depression Scale (HAMD). Secondary outcomes are Self-Rating Depression Scale (SDS), Depression Scale of traditional Chinese medicine (Depression Scale of TCM), brain fMRI and blood biomarkers including neurotransmitters 5-HT, DA, NE, inflammatory cytokines IL-1β, TNF-α, IL-6 and neurotrophin BDNF. All the outcomes will be assessed at baseline, 4 weeks after EA treatment onset and 6-month follow-up.

Discussion

The results of this trial will verify the efficacy and safety of EA treatment for depressive patients and provide acupuncturists and clinicians with robust clinical evidence.
The social media intervention for lower back pain education study (SMILE): a protocol for a randomized trial to reduce occupational low back pain in nursing professionals
Authors: Kazemi Seyedeh Somayeh , Tavafian Sedigheh-Sadat , Montazeri Ali 
Published: July 2019

Abstract
Background Low back pain in nursing profession remains an important health issue. This study aims to assess whether a theory based interactive social media intervention could change job-related risk behaviors among nursing personnel. Methods This is a community-randomized controlled trial. Three settings of hospitals will randomly be assigned to the study arms: Intervention setting 1 receiving an in-person educational package; intervention setting 2 receiving the same material a web-based; and a control setting receiving nothing. The intervention would contain materials related to occupational risk behaviors and will try to promote the knowledge, attitude, skill, and self-efficacy of nurses on low back pain preventive behaviors. The primary outcome will be reduction in low back pain. The study also will assess whether the intervention could reduce pain-related disability and improve the quality of life. Discussion Occupational low back pain among nurses could adversely affect both patients and nurses’ health. This study is an attempt to see if social media could play a role to guide the development and implementation of future interventions.