bluuebunny/crossref_metadata_2025 huggingface dataset:
Margaret Storm Jameson and the Spanish Civil War : The Fight for Human Values
Authors: Birkett Jennifer
Published: November 2018

Spain is not generally thought of as a significant theme in Jameson’s writing, or her political formation. But careful study of her life and writing discloses numerous connections to the country from the early 1930s onwards, and No Victory for the Soldier (1938), the novel she published under the pseudonym of James Hill, in the 1930s, closes with a lengthy section on the Spanish Civil War. The tragic heroism of the Republic at war provides the ideal context for Jameson’s exploration of the capacity of modernist art, or rather, modernist artists (the Auden generation) to speak in the name of the future of the common man. Spain, and especially the Basque country, fighting the fascist war machine, is one of the last repositories of humane living and European values: reason, justice, humanity and decency.
Educação escolar indígena Mehî (Krahô). Das possibilidades da Caxekwýj e outras histórias na escola
Authors: Jokakwyj Letícia
Published: November 2018

Este texto busca problematizar práticas pedagógicas coloniais ainda presentes na escola Krahô. Mais especificamente se pensa sobre a importância das histórias dos antigos para a formação das crianças e jovens mehi (indígena). Simultaneamente, questiona-se a disciplina história, presente na grade curricular das escolas Krahô. Em primeiro lugar, do ponto de vista de seu conteúdo, a história é contada quase sempre a partir da narrativa não indígena. Em segundo lugar, a narrativa se adapta por sua forma a um modelo disciplinar de educação, ou seja, de uma maneira que fragmenta o conhecimento e o elabora a partir de uma episteme ocidental.
Application of experimental designs for genetic study
Authors: Mandal B. N. , Dash Sukanta , Kumar Anil , Kumar Devendra
Published: November 2018

Design of experiments are mainly consist of two parts. One as construction and second is data analysis using the inference drawn. In this article we have described some of the methods used for diallel crosses and partial diallel crosses in plant breeding. A procedure for analysis of these type of designs was also described in sequel. These type of experiments are generally used for both animal as well as plant breeding experiments. An illustration of the analysis of mating designs is also described with results.
Effect of crop regulation practices on yield and economics in Guava (Psidium gjajava L.) fruit crop
Authors: Gurjar Praveen Kumar Singh , Lekhi Rajesh , Singh Lal
Published: November 2018

An experiment on the effect of crop regulation practices on Guava fruit crops was conducted during 2016-17 and 2017-18. The results revealed maximumand statistically higher yield (119.73 q/ha.), gross return (Rs 32925 per hectare) and Net return (Rs230529 per hectare) under application of 800 PPM NAA plant growth regulator. Highest cost benefit ratio (1:3.33) was also recorded under the treatment of 800 ppm of NAA which was most economic and feasible practice of crop regulation in guava fruit crop.
Diagnosis of various pathological conditions causing mortality in Asian koels (Eudynamys Scolopaceus)
Authors: Manjunatha V. , Rout M. , Satish R. , Muniyellappa H.K. , Byregowda S.M.
Published: November 2018

Asian koel (Eudynamys scolopaceus) belongs to a member of the Cuculiforme order of birds, the Cuculiformes and like other birds they are prone to many infectious and non-infectious conditions. In the present study, various pathological conditions observed during necropsy of Asian koels were summarized. A total of 15 Asian koels of different age groups were received from the Wild Animals Rescue and Rehabilitation Centre, Bannerghatta for necropsy during the year 2014 to 2016. Gross and microscopic findings observed were suggestive of various pathological conditions affecting various systems towards the probable cause of death. Most of the avian diseases were also prevalent in Asian koels and hence warrants proper attention towards their prevention and control measures.
Molecular epidemiology and phylogenetic analysis of foot and mouth disease virus type ‘O’ and evaluation of its carrier state in cattle of Assam by Real time PCR
Authors: Baro Sangeeta , Sharma Krishna , Sharma Biswajyoti , Tamuly Shantanu , Deka P. , Boro Prince , Das S.K.
Published: November 2018

The molecular epidemiological study of foot-and-mouth disease virus (FMDV) has been carried out from different outbreaks in Assam the present study is based on the nucleotide sequencingof circulating FMDV serotype. The samples were subjected to sandwich ELISA, multiplex-PCR and molecular phylogeny to identify the type species. The phylogenetic analysis of virus sequence revealed similarity with theBangladesh isolates in the major branching pattern. The serotype ‘O’has found to be dominant and responsible for most of the recentoutbreaks.Thepersistence of serotype ‘O’ and cytokines expression of IL-1á, IL-1â, IFN-á, TNF-á in blood of recovered animals were done by Real time PCR. The findings indicated that IL-1á, IFN-á and TNF-á genes were up-regulated upto 3 months post infection but IL-1â found to be down regulated with progression of recovery. The present study thus supports that real-time PCR is a powerful technique for reliable detection of persistent FMDV in recovered animals.
Prevalence of bovine tuberculosis in buffaloes in Hyderabad and Tando Allahyar districts of Sindh, Pakistan
Authors: Malhi Kanwar Kumar , Kamboh Asghar Ali , Kumar Chandar , Dewani Prakash , Kumar Mukesh , Abro Shahid Hussain , Leghari Ambreen , Wang Xiaolan , Yu Shengqing
Published: November 2018

An investigation in buffaloes was carried out in Hyderabad and Tando Allahyar districts, Sindh province, Pakistan to determine the prevalence of bovine tuberculosis. The buffaloes (n=120) were first screened through single intradermal tuberculin test (SITT), then their sera were used for enzyme-linked immunosorbent assay (ELISA). Attempts were further made to isolate the Mycobacterium bovis organism from the milk samples using traditional culture test. Overall prevalence of 4.16%, 8.33% and 2.5% was recorded by SITT, ELISA and culture test respectively. A somewhat higher prevalence was recorded in Tando Allahyar district (SITT 6.66%; ELISA 10%; culture test 5%) as compared to Hyderabad district (SITT 1.66%; ELISA 6.66%; culture test 0%). Statistical analysis did not show any association (P> 0.05) of herd size, sex, age, milk yield and farming type with the prevalence of the disease. Whereas, SITT showed a significant (P Less than 0.05) association of sex, age and milk yield with the prevalence of the disease in Tando Allayer district. The results of present study revealed that bovine tuberculosis is present in apparently healthy buffalo herds of Hyderabad and Tando Allayer districts. Moreover, infected animals shed the M. bovis pathogen in milk that could be a potential hazard to public health.
A general construction of mutually orthogonal latin squares of prime order
Authors: Saka J. A. , Oyadare O. O.
Published: November 2018

This paper presents a general method of constructing a complete set of Mutually Orthogonal Latin Squares (MOLS) of the order of any prime, via the use of generating functions dened on the nite eld of this order. Apart from using the generating function to get a complete set of Mutually Orthogonal Latin Squares, the studies of the generating functions opens up the possibility of getting at the deep structural properties of MOLS. Copious examples were given for detailed illustrations.
The Origin of the Most Energetic Galactic Cosmic Rays: Supernova Explosions into Massive Star Plasma Winds
Authors: Biermann Peter , Kronberg Philipp , Allen Michael , Meli Athina , Seo Eun-Suk
Published: November 2018

We propose that the high energy Cosmic Ray particles around the spectral turn-down commonly called the {\it knee} and up to the upturn, commonly called the {\it ankle}, mostly come from Blue Super Giant star explosions. At the upturn, i.e. the {\it ankle}, Cosmic Rays probably switch to another source class, most likely extragalactic sources. To show this we recently compiled a set of Radio Supernova data to list the magnetic field, shock speed and radius scale (Biermann et al. 2018) \cite{Biermann18}. Using particle acceleration theory at shocks, those numbers can be transformed into characteristic {\it knee} and {\it ankle} energies. Without adjusting any free parameters both of these observed energies are directly indicated by the supernova data. We now proceed to the next step in the argument, and use the Supernova Remnant data of the starburst galaxy M82. Assuming that they are Blue Supergiant star explosions, the shock will race to their outer edge with a magnetic field that follows ${B (r) \, r \, \sim \, const.}$. We argue that the shock runs through the entire magnetic plasma wind region at full speed all the way out to the wind-shell, which is of order parsec scale. The speed is observed to be $\sim \, 0.1 \, c$ at about ${10^{16} \, {\rm cm}}$ radius in the plasma wind. This demonstrates how Blue Supergiant star explosions can provide the Cosmic Ray particles across the {\it knee} and up to the {\it ankle} energy range. The data from the CREAM (Cosmic Ray Energetics and Mass Experiment) mission will test this cosmic ray concept which is reasonably well grounded in two independent radio supernova data sets. The next step in developing our understanding is to obtain accurate Cosmic Ray data near to the {\it knee}, and use unstable isotopes of Cosmic Ray nuclei at high energy to probe the "piston" driving the explosion. We plan to combine these data with the physics of the budding black hole which is probably forming in each of these stars to learn more.
Formulated Mathematical Model for Delayed Particle Flow in Cascaded Sub-Surface Water Reservoirs with Validation on River Flow
Authors: Richard Ombaki , Joash Kerongo , M. James Okwoyo
Published: November 2018

Pollution of sub-surface water reservoirs mainly rivers and streams through contaminated water point sources (CWPS) was studied. The objective was to formulate a discrete time delay mathematical model which describes the dynamics of reservoir pollution using mixing-problem processes that involve single species contaminants such as nitrates, phosphorous and detergents. The concentration  of pollutants was expressed as a function of the inflow and outflow rates using the principle for the conservation of mass. Systems of ODEs generated from principles of mixing problems were refined into a system of DDEs so that the concentration of pollutant leaving the reservoir at time would be determined at some earlier instant, for the delay. The formulated model is a mathematical discrete time delay model which would be used to describe the dynamics of sub-surface water reservoir pollution. The results from the validation of the model were analyzed   to determine how time delays in the mixing processes affect the rate of particle movement in water reservoirs.
The Role of Body Weight and Growing in Body Height to Nonspecific Musculoskeletal Pain in a Cohort of Bosnia and Herzegovina Schoolchildren
Authors: Pranjic Nurka , Azabagic Selma
Published: November 2018

Background Children often suffer the nonspecific musculosceletal pain as reported in literature. Aim To determine relationship between body weights with development of musculoskeletal pain and to determine whether growing in body height is associated with musculoskeletal pain in schoolchildren. Subjects/ Methods A prospective longitudinal study included 1315 school children aged 7-14 years (652 boys and 663 girls) and was performed in 13 elementary schools in B&H. Child body height and body weight were measured. The survey of perception of musculoskeletal pain in different body regions of subjects was conducted by adjusted Nordic Musculosceletal Questionnaire (NMQ). Results The highest prevalence of an overweight and obesity in the 10th year 35.7% and the lowest frequency 17.8% in the 14th year was. In the age 14th obesity was’nt found. Boys have more prevalence of overweight. Using logistic regression model, we found that school children with normal BMI were protected with increased body height of acute lower back pain (β= -0.089, 95%CI, -9.730- -0.023, P< 0.049), and increased body height was protector of obese school children of acute upper back pain (β= -0.356, 95%CI, -14.077- -3.878, P< 0.001) and chronic lower back pain (β= -0.356, 95%CI, -14.077- -3.878, P< 0.001). Conclusion Schoolchildren with normal weight more often have had musculosceletal pain than those with overweight or obesity. This can be associated with intense physical growth period in height, especially. The assumption is that the increase in height changes the relationship between excessive BMI and musculoskeletal pain in children of school age.
High-throughput of measure-preserving integrators for constant temperature molecular dynamics simulations on GPUs
Authors: Guarneros-Nolasco Luis , Terrón-Mejía Ketzasmin A. , Mulia-Rodríguez Jorge , Osorio-Gonzalez Daniel , López-Rendón Roberto , Rodriguez-Romero Felipe
Published: November 2018

Molecular dynamics simulation is currently the theoretical technique eligible to simulate a wide range of systems from soft condensed matter to biological systems. However, of the excellent results that the technique has arrogated, this approach remains computationally expensive, but with the emergence of the new supercomputing technologies bases on graphics processing units graphical processing units-based systems GPUs, the perspective has changed. The GPUs allow performing large and complex simulations at a significantly reduced time. In this work, we present recent innovations in the acceleration of molecular dynamics in GPUs to simulate non-Hamiltonian systems. In particular, we show the performance of measure-preserving geometric integrator in the canonical ensemble, that is, at constant temperature. We provide a validation and performance evaluation of the code by calculating the thermodynamic properties of a Lennard-Jones fluid. Our results are in excellent agreement with reported data reported from literature, which were calculated with CPUs. The scope and limitations for performing simulations of high-throughput MD under rigorous statistical thermodynamics in the canonical ensemble are discussed and analyzed.
Qualification and Implementation of Oil-Based Mud as a Cost-Effective and Low-Damaging Perforation Fluid for High-Pressure/High-Temperature Fields: Gudrun Case History
Authors: Fleming Niall , Karunakaran Mary , Hireche Sammy
Published: November 2018

With an increasing focus on identifying cost-effective solutions to well design with a minimal impact on productivity, this paper will focus on an alternative to cesium (Cs) formate as the perforation fluid in the high-pressure/high-temperature (HP/HT) Gudrun Field operated by Equinor. Cs formate has been used with success for drilling and perforating many HP/HT wells. However, because of the significant cost of this fluid coupled with low oil prices, Equinor wanted to perform testing to assess the performance of an alternative oil-based mud (OBM) as a perforation fluid. In this paper we describe the extensive qualification testing that we have conducted, which includes coreflooding using representative plugs from Gudrun Field under downhole temperature and pressure conditions. In addition, eight API RP19B (2014) Section IV perforation tests have been conducted to compare the performance of the Cs formate with the OBM. These tests were undertaken using gas- and oil-saturated cores to reflect different production scenarios. The main aspects of the perforation operation that were reflected in the test design were as follows:

Perforating at a reservoir pressure and a laboratory-testing temperature of approximately 100°C Simulating an extended shut-in period after perforation Undertaking a cleanup sequence using scaled-down flow rates

On the basis of the results of the coreflooding combined with the API RP19B (2014) Section IV testing, the OBM was selected as the perforating fluid for use on Gudrun Field. The perceived benefits of using the OBM were as follows:

Simplification, by using the same fluid for drilling and perforating the reservoir section Tangible time savings and cost savings in the fluid cost of approximately 40 million NOK (USD 5 million) Potentially increased productivity compared with the Cs formate Improved standardization of the operational sequence

Perforation modeling is described, and a comparison is made between this and the API RP19B (2014) Section IV tests. Finally, the well-startup experiences and the production data are presented, demonstrating the effectiveness of the OBM as a perforation fluid.
How Personality Tendencies Impact Performance
Authors: Fisher Rob , Senior Garcia David
Published: November 2018

This interactive session is intended to inform attendees of the impact our personality tendencies have on how people see, manage and mitigate risk. Our research and practical application have shown that expanding the understanding of traditional human factors and human and organizational performance to include personality elements results in a further developed body of knowledge, enhancing traditional methods of reducing errors, events and incidents.

We have gathered, analyzed and verified over 500,000 personality tendency data points related to how people behave in given situations, communicate, lead and see and manage risk. Where most ‘personality typing’ regimens focus primarily on how people behave and interact with others, we have paid specific attention to how human performance error traps impact different personalities, how and why we follow or don't follow procedures, and what we can do about it. The data associated with "what makes it difficult for me to stop work" and "how could I get hurt" has been game-changing in understanding and managing risk at all levels of the organization. Many of the standard human and organizational performance error reduction tools do not effectively consider that different people need different types of information to effectively use the tools to reduce the probability of error.

The overall conclusion of the last ten years of gathering and analyzing the data is that different people with different personality tendencies see, manage and mitigate risk differently. Understanding this critical element will allow organizations to reduce errors and incidents, especially on critical or high-risk tasks. In addition, taking these elements into account drives more effective and usable procedures and processes that more people adhere to. Several methods will be discussed as to how attendees can immediately put into action some of the new understandings.

The 10,000 volunteers at Super Bowl 51 in Houston, TX used some of this understanding to improve interactions with visitors. Schools around the globe are using awareness and management of personality tendencies to reduce bullying, decrease absenteeism, improve engagement, and increase graduation potential.

Traditional safety, engineering, human factors, and human & organizational performance approaches do not effectively account for personality tendencies in a way that minimizes risk. From the oilfield, to electric power generation and distribution, to construction and manufacturing, these techniques have been used to effectively reduce and mitigate risk, improve engagement, and improve organizational safety culture.
Efficiency and Innovation for Borehole Seismic Acquisition in a Well Completed with Permanent Fiber: DAS Technology for Saving Time and Minimizing Risk
Authors: Ferla Maurizio , Miranda Francesco , Nutricato Giacomo , Galli Giuseppe , Moriggi Sara , Malossi Alfio , Guglielmo Carmelo , Tesconi Marcello , Mangione Alessandro , Stocchi Donatella , Naouar Aymen , Bettinelli Pierre , Manai Nabil , Slail Osama , Pagnin Andrea
Published: November 2018

Efficiency is a key factor on any operation. In this paper, we introduce the heterodyne Distributed Vibration Sensing (hDVS), which is an innovative technology based on fiber optic system to improve the duration of borehole seismic operations.

We designed a survey aimed at comparing standard downhole geophone accelerometers measurements to i) optical fiber seismic installed inside the hybrid Wireline cable and ii) optical fiber clamped permanently to the well completion tubing. This comparison was conducted using a standard rig source VSP in association to advanced Offsets VSP. The purpose of the study was to evaluate this innovative technology and to assess the feasibility of drastic operation time reduction without compromising output data quality.

To better evaluate the readiness of the technology, we decided to compare three distinct types of downhole measurements and designed a specific advanced acquisition which allowed us to compare various configurations. Consequently, the borehole seismic acquisition performed in the MR-SE1 well located in Makhrouga field (Tunisia) was split into two phases. Phase #1: during open-hole Wireline logging, using the standard downhole geophone accelerometers (VSI) and fiber optic seismic cable (single-mode cable) installed inside the Wireline logging cable (called hybrid Wireline cable). Phase #2: at the departure of the drilling rig, using a fiber optic seismic cable (single-mode cable) installed permanently along the intelligent completion. The results highlight the effectiveness of the hDVS technology with a proven decrease on operation timing, with reliable and good SNR recorded data.

Nowadays, efficiency is a key requirement for any data acquisition process. The heterodyne Distributed Vibration Sensing (hDVS) is an innovative technology designed to achieve such effectiveness by making the Vertical Seismic Profile (VSP) a matter of minutes instead of hours, as using standard downhole equipment, without compromising output data reliability and allowing the measurements repeatability (no well interventions required).

Finally, based on the quality of the dataset acquired, further analysis can be conducted for imaging purpose by analyzing the reflected waveforms, which could bring additional information and could change the way we are operating.
Comprehensive ICD/ICV Completion Design Workflow Practiced in Green Oilfield Offshore, Abu Dhabi
Authors: Javid Khalid , Mustafa Hammad , Chitre Sunil , Anurag Atul , Sayed Mohamed , Kuliyev Myrat , Mishra Anoop , Al Hosany Khalil , Saeed Yawar
Published: November 2018

The workflow is implemented for designing Lower completion with inflow control devices &/or inflow control valves (ICD/ICV) for high departure long horizontal wells in a Green Field located North West offshore Abu Dhabi. The major challenges that being faced in the field development include reservoir heterogeneity with high permeability contrast ranging from 0.1 to 500 md, fault network and high uncertainty about Tar Mat surface & Oil Water contact.

Main objectives of ICD/ICV completions are; to have uniform influx/flow profile from all sublayers of reservoir by dividing horizontal drain in compartments based on reservoir properties variations, minimize heel to Toe effect, controlled inflow from high permeability streaks, without compromising total well deliverability; most importantly to encourage more inflow from the lower permeability regions.

The ICD/ICV Completion design workflow utilized in the industry and available in literature was followed along with new improved & integrated approach of dynamic simulation modelling. An appropriate reservoir sector model having one deviated gas injector, one/two horizontal water injector(s) and one ICD/ICV candidate oil producer was extracted to be used for this study.

Single time step static modelling and dynamic sector modeling simulation approaches were implemented for ICD/ICV modeling. The dynamic simulation model workflow included Local Grid Refinement across the candidate well & gas injector along with well segmentation. Sensitivity & optimization cases include Open hole (base) case, ICD/ICV completions with different nozzles sizes, and varying compartment/segment lengths for better control & improving oil flow profiles, and cumulative oil production.

This workflow has provided valuable design data prior to drilling this challenging horizontal well candidate, lower completion equipment allocation based on compartment requirements and final optimization of ICD/ICV after receiving open hole logs; where latest suit of logs were run, are discussed in this paper.

The completion design of the well resulted from this workflow included ICD configurations with swell packer arrangements to create 8 compartments along the reservoir section. Simulation results from ICD/ICV completion proved successful in delaying water & gas breakthrough in representative multi-well dynamic sector model.

This Workflow adopted by the team in designing the lower completion resulted in successful installation of the ICD(s) & ICV(s) in the field for various oil producer wells.

This paper also covers the challenges being faced while real time fine tuning of ICD/ICV design model. This workflow would be useful for any future designing & applications of this type of smart completions for any field worldwide with similar challenges.
Investigation of Barrier Water Injection at Gas-Oil Contact as Co-Development Plan for Gas Cap Reservoirs
Authors: Sharif Ahmed
Published: November 2018

A numerical simulation study was conducted to explore feasibility of gas cap and oil column co-development plans. Unlike conventional development schemes that entail to optimally produce first from oil column while deferring gas cap development, the co-development strategy studied here involves simultaneous production from oil column and gas cap. The drive mechanism consists of down-dip peripheral water injection for oil column in conjunction with barrier water injection at or near gas-oil contact that is designed to separate the gas cap from the oil column and thereby facilitate gas production. The basic objective of the study is twofold: to assess the merits of the concept of barrier water injection and to identify key subsurface and operational parameters that have most significant impact on oil and gas recovery. Extensive numerical simulations were conducted to explore the conditions under which the concept of barrier water injection is favourable as a recovery process. Important issues related to the viability of the development concept are how fast a barrier water can be established, how long it can be sustained and how many wells are needed. Furthermore, effects of gas cap relative size, reservoir geometry (e.g., dip-angle and surface area of the gas-oil contact), trapped gas, rock heterogeneity and off-take rates have been investigated in detail. The work shows that the feasibility of the co-development scheme is mainly controlled by pressure maintenance and balance of injection, relative size of gas cap, reservoir geometry and rock heterogeneity.
Chasing Middle Cretaceous Stratigraphic Traps in Offshore Abu Dhabi by Incorporating 3D Seismic Data into Machine Learning Methodology
Authors: Caeiro Maria Helena , Neves Fernando , Taher Ahmed
Published: November 2018

The aim of this study is to explore the Middle Cretaceous hydrocarbon potential particularly associated with prograding units. A machine learning based methodology is applied to evaluate the exploration potential of the Cretaceous Mishrif clinoforms in offshore Abu Dhabi, where a recent high-quality 3D seismic data have been acquired. The exploration objectives are to perform structural interpretation of the play; to infer reservoir quality, such as porosity; and to characterize the internal geometry of the reservoir and its seismic lithofacies.

Machine learning is a branch of artificial intelligence (AI) that plays a crucial role for evaluating data and building knowledge. In the context of subsurface characterization, the integration of AI into hydrocarbon exploration brings a substantial value for appraising different plays in a faster, robust and reliable manner. This is especially relevant in early exploration stages, when the availability of well data is limited but huge amount of high quality seismic data exist. Advantages of applying machine learning algorithms are its capability (1) to deal with several types of information and large 3D seismic data; (2) to learn by themselves from these data; and (3) to assist in interwell pre-drill estimates and associated uncertainties in a semi-automated context.

Seismic inversion is a process that integrates both 3D seismic and well data to derive reservoir properties. The seismic derived elastic models can be incorporated in reservoir modelling stage as secondary data, indicating the variability of the properties where there is no well information. Moreover, assessing the uncertainty related to reservoir quality of the Mishrif play will allow more effective exploration decisions, such as well placement and volumetric estimations.

Clinoforms depositional surfaces are identified in the seismic inverted elastic models, displaying lateral variation in geometry and reservoir properties. Given the high correlation achieved between acoustic impedance and log-porosity, it is infer with relative high confidence that better porosity development is expected to be found at the topmost part of the clinoforms. The quality of the reservoir is anticipated to degrade towards the edge of the clinoforms. Hydrocarbon charge model from the nearby Shilaif source rock kitchens will be incorporated to reduce the risk of future exploration activities in the area.
Optimal Thermowell Design Improves Plant Safety & Integrity
Authors: Ganesan Sankara Subramanian
Published: November 2018

The intent of this paper is to highlight the enhancements in latest Performance Test Codes (ASME PTC 19.3), evaluate the causes of failures occurred in thermowells and define the importance of optimal thermowell design.

Failure of a thermowell can have catastrophic consequences, which results in loss of containment and affects the plant safety, integrity & profitability. Hence, an efficient design, the proper selection and the operation within limits are essential to achieve 100% HSE and ensure a fit-for-future service.
Collaborative Approach to Bit Development for Drilling Abrasive Formations in Browse Basin
Authors: Edge David , Sadawarte Sagar , Shepherd Aaron , Spoljaric Hrvoje
Published: November 2018

A development programme offshore Western Australia required near horizontal 8.1/2" wellbores to be drilled through challenging formations. The hole section intersected sand-shale interlayers, referred to as the Tiger Sands, which is an abrasive formation with unconfined compressive strength (UCS)between 15,000psi and 20,000psi, with maximum UCS recorded up to 30,000psi. Underlying the Tiger Sands is the well cemented, abrasive Brewster sandstone with average UCS of 15,000psi and maximum UCS recorded up to 21,000psi, which has demonstrated a propensity to natural fractures. These challenges resulted in poor bit durability, low rate of penetration (ROP), difficult directional control,excessive shocks and downhole vibrations and significant downhole mud losses. The complexity of the drilling conditions required a systematic approach to be employed to optimise the poly-diamond crystalline (PDC) drill bit solution in order to improve durability and optimise ROP while successfully managing directional control, losses and ultimate drilling cost through the interval.

In addition to drill log analysis, after operations reviews (AORs) provided a comprehensive summary of operations from a rig perspective. These summaries were then used by the onshore engineering team to work in collaboration with the service sompany engineering team to develop a bit optimisation strategy. The first development well of the campaign was drilled with a standard 8 bladed 13mm PDC bit.

Natural fractures were penetrated and a total of ~4,500bbl of synthetic sased sud (SBM) was lost to the formation. The bit suffered impact damage and, therefore, had reduced durability. To solve thisproblem, a systematic approach was followed to gradually introduce improved design elements. Bit design progressed from cutter design, improved technology and ultimately, the introduction of new PDC cutter technology to record the fastest on bottom ROP for the drilling campaign of 10.32m/hr. Improved ROP and optimisation of the loss treatment strategy, allowed drilling operations to continue with minimal exposure to losses when present. Positive AOR feedback and continuous development from the service company resulted in further improvements to the PDC bit design with the introduction of ridged diamond elements and the latest generation conical elements to further improve steerability and ROP.

Continued developments resulted in New Design 4 being run in well 10. The entire interval was drilled in one run with excellent steerability and an overall 159% improvement in ROP equating to a reduction in drilling time by 5 days going from the original 813 PDC to the final New Design 4. In addition to ROP improvements, losses did not prove prohibitive to reaching TD due to drilling efficiency. Subsequent further improvements in ROP have been realized, with the entire interval drilled at 16m/hr.
PWHT Requirement for Submarine Pipelines Challenges and Way Forward
Authors: Singh Nawin , Kulshrestha Manoj , Nair Sajith
Published: November 2018

The objective of this study is to assess the provision of Post Weld Heat Treatment (PWHT) of girth weld on C-Mn steel submarine pipelines and propose an alternative to avoid PWHT. As per prevailing industry practice, the majority of the existing submarine pipelines handling sour service fluid, limit the steel grade to 450 MPa SMYS (X65). Such limitations on steel grade for sour service application results in high wall thickness especially for high pressure pipelines. This necessitates stress relieving requirements and hence leads to an uneconomical scenario for the project. Performing PWHT for girth weld of submarine pipelines is neither practical nor a cost- effective solution for the project.

The stress relieving requirement of girth weld is linked with pipeline wall thickness and such limitations on thickness varies based on selected governing design code for the submarine pipeline system.

ASME Pipelines Code has exempted PWHT to 32 mm of pipe wall thickness and such a limit is quite often surpassed for large diameter high pressure gas pipelines designed using Grade X65 steel.

To eliminate the need for impractical (in most cases) and expensive offshore PWHT, available alternate options include use of higher strength steel of grade X70 or above. However, in certain cases even higher steel grades do not help in elimination of the stress relieving requirement. Performing PWHT may further result in restricting the larger diameter (i.e. seam welded) pipe material to non-TMCP (Thermo Mechanically Controlled Processing). In such cases, necessary engineering analysis as per the provisions of pipeline design code needs to be performed. This paper discusses a systematic approach based on the provisions made in the Design Standards for waiver of PWHT, with further detailed engineering assessment based on fracture mechanics. A case study has been discussed the feasibility of PWHT waiver.

This paper will address the current limitation of using a higher grade of steel (e.g. X70, X80, etc.) for sour service and submarine applications. Provisions made in Design Standards for waiver of PWHT shall be evaluated by demonstrating an alternate method using fracture mechanics duly supplemented with engineering assessment.

Results from the case study substantiated by detailed engineering critically assessment (ECA) show that the acceptance criteria can be achieved without the requirement of PWHT. The mechanical properties of weldment are also acceptable without having stress relieving of the pipeline girth weld. A suitable methodology is discussed and presented to adopt in case such scenario arises for designing the submarine pipeline system.
De-Risking Chemical EOR Application in the Sabriyah Lower Burgan Reservoir through the Design of a Large-Scale Field Application
Authors: Al-Ghnemi Mohammad , Ozkan Erdal , Al-Murayri Mohammed , Pitts Malcolm , Dean Elio
Published: November 2018

The Sabriyah Lower Burgan (SALB) is a multi-billion-barrel reservoir located in north of Kuwait with favorable fluid and rock properties, with the addition of a strong active aquifer. The presence of the aquifer is favorable for primary development of the field but is a challenge for chemical EOR. The objective of this study is to identify the key challenges to be managed to increase the probability of success for a large-scale field implementation. The SALB has passed multiple stages of the EOR process (technical screening, laboratory formulation design, SWCT, pilot design) and is currently in the implementation phase for chemical EOR pilot. This paper assumes that the pilot is successful and addresses larger scale implementation concerns. It discusses the necessity of a large-scale multi-well pilot to evaluate economic viability and considers the risks of large-scale chemical EOR implementation in Sabriyah Lower Burgan. Three challenges are documented as key risks that can jeopardize a large-scale field implementation: (1) EOR Chemical/water incompatibility with reservoir, (2) economic factors, and (3) geologic features such as the aquifer.

The key findings and conclusion of this paper is the use of Monte Carlo simulation on reservoir simulation and economic parameters to evaluate their impact on the success of the project and outline the main risk parameters.
Production Potential of Shilaif Formation in UAE Using an Integrated Reservoir Characterization Approach
Authors: Alzaabi Mohamed A. , Uzun llkay , Eker Erdinc , Kazemi Hossein , Ozkan Erdal
Published: November 2018

As a result of shale oil and gas production success in the United States, development of shale resources elsewhere around the world has gained great interest. In the Middle East, where much of the world's conventional reserves are located, huge investments have been deployed to evaluate the potential of shale reservoirs. In this paper, we present an integrated reservoir characterization study of Shilaif shale formation in the United Arab Emirates, which includes an assessment of the primary production from a test well using a multi-phase, dual-porosity model. We also evaluated enhancing production performance via improved well completion.

In characterizing Shilaif's unconventional shale reservoir potential, we developed an integrated plan and workflow that included gathering and assessing the geological, petrophysical, and production data from a horizontal exploration well. The data used in the workflow included well-logs, cores, completion information, and pressure transient and production data from the well. The analysis of pressure build-up data ensuing the rate-transient period provided an estimate of effective formation permeability, which is a unique aspect of this study because such tests are not routinely conducted in shale reservoirs. The hydraulic fracture stimulation had improved the effective permeability nearly two orders of magnitude compared to the matrix permeability from cores and well logs. For the ultimate assessment and future performance, we developed a multi-phase dual-porosity numerical model. The simulation model was used to history-match the production data of hydraulically fractured horizontal well in Shilaif formation and case studies were conducted to evaluate the production potential.

For future development plans, it was determined that decreasing the fracture spacing from 250 feet to 150 feet was not economically feasible because the incremental production was around eight percent during the first year of production. Nonetheless, the simulation model indicated that Shilaif's large shale reservoirs may be viable for future development targets in the Middle East arena.
Successful Implementation of Torque and Drag Management Techniques in High Departure Wells is the Key to Safely Reach Wells Planned Total Depth in Offshore Artificial Islands
Authors: Diaz Nerwing , Paila Phalgun , Kirby Cliff , Akl Bassam , Mahmoud Dalia , Al Kindi Rashid Khudaim , Kasem Youssef , Benygzer Mhammed , Haddad Mohamed , Leon Vicente
Published: November 2018

Directional drilling from artificial islands has become a common offshore practice in the United Arab Emirates, looking to minimize footprint while optimizing cost to reach maximum number of targets from a single location. This drilling practice brings some challenges such as torque and drag limitations, which is vital in order to safely reach wells total depth in well profiles with a high departure. The purpose of this paper is to discuss in detail the successful implementation of torque reduction techniques, focused on case histories from an artificial offshore island in the United Arab Emirates.

During the planning phase, Drilling Engineers estimate expected torque and drag for the different sections based on modeling and historical data, this process is key to assess the limitations and initiate the process of evaluating the different torque and drag reduction techniques to be implemented based on the application. The case histories presented in this paper show the successful implementation of proven torque and drag management techniques, such as; well profile optimization, torque reduction subs, deployment of lubricated mud, use of real-time directional data to minimize hole tortuosity, and deployment of Rotary Steerable Systems from top to bottom for improved hole quality.

There are different factors considered in the planning phase that make torque and drag management crucial, but drill pipes torque limitation was the main challenge to overcome in order to reach planned total depth in the case histories discussed in this paper. Wells trajectory and BHA optimization played an important role during the execution phase, as well as the deployment of lubricated mud and torque reduction subs which in conjunction provided an overall surface torque reduction of up to 28%.

The implementation of different torque and drag reduction methods are illustrated with the modeling results and actual drilling data collected during the drilling of these wells. Information and data discussed in this paper can serve as documentation to aid in the planning phase for wells with similar challenges.
Optimization of Gas Lift Throughout the Well Lifecycle in Unconventional Reservoirs
Authors: Ayoub Joseph , Gao Sunhua , Jin Bikai , Blakey Brian , Krishnamurthy Shalini , Thambynayagam Michael
Published: November 2018

Given the pronounced nature of production decline in shale reservoirs, an integrated reservoir-well model that can efficiently anticipate the changes in reservoir and lift parameters over time is required in order to maintain optimum performance. The solution presented in this paper uses a novel integrated reservoir-well model specifically tailored for unconventional reservoirs to calculate the system deliverability and optimize gas injection throughout the well life. The integrated model is deployed in the cloud. It enables automation of the above process and allows more valuable exploitation of oilfied sensors such as multiphase flowmeters and of process control equipment in digital oilfields.

The model calculates for each well, the oil rate versus gas injection rate at any time during the well lifecycle by simultaneous solution of the reservoir transient IPR and the wellbore model. The resulting gas demand displays the typical maximum oil production and corresponding maximum gas injection rate beyond which oil rates would decline. The derivative is then used to calculate the gas injection rates versus time that meet a specific predefined economic objective. Single-well and multi-well scenarios are investigated and the impact of gas supply limit is evaluated to illustrate the practical applicability of the solution. Examples illustrate how the gas allocation among the different wells is calculated to achieve the optimum impact. Comparison of the production when gas injection supply is unrestricted versus production results with restricted gas supply is made and results of staggered production are presented.
Improved Zonal Isolation Achieved with Novel Scrubbing Spacer Deployed in Saudi Arabia
Authors: Al Mutahr Ammar , Shine Joe , Taoutaou Salim , Bazuhair Mohammed , Al-Sahlawi Ziyad , Jaafari Ahmed
Published: November 2018

Zonal isolation is reliant on successful cement placement. Part of the key criteria to achieve zonal isolation includes effective mud removal and fluid displacement efficiencies. To meet the mud removal requirements, a spacer system promoting physical or mechanical scrubbing appears to increase the efficiency of filter cake removal. The spacer has been deployed in Saudi Arabian wells containing water- and oil-based mud systems. For any given application, this paper discusses advanced laboratory testing to obtain performance properties such spacer stability and spacer integrity while managing the downhole plugging risks. This paper will document examples demonstrating results the spacer performance including cement evaluation logs supporting the use for achieving similar cement placement objectives.
Miscibility Effects on Performance of Cyclic CO2 Injection in Hysteretic Tight Oil Reservoirs
Authors: Assef Yasaman , Pereira Almao Pedro , Pourafshary Peyman
Published: November 2018

Dependency of relative permeability on saturation path during cyclic CO2 injection (CCI) in various operational constraints affects the oil recovery in different ways. A compositional reservoir sector model is built based on the available production data of hydraulically fractured horizontal well in Bakken formation. The work discusses the simulation results of the CCI and investigates the contributions of non-wetting phase's relative permeability hysteresis in oil production below and above the minimum miscibility pressure (MMP).

A CMG-GEM model is built based on the Bakken geological settings, well production and live oil PVT data. Relative permeability hysteresis model is incorporated within the simulator using the Killough's method. A cyclic CO2 injection (CCI) EOR scheme is designed and implemented in the numerical model. Effects of structural trapping and hysteresis-induced CO2 /gas retardation on oil recovery are studied during CCI in which a strong flow reversals may occur.

The results of simulation revealed that in non-hysteretic model, performing cyclic CO2 injection at immiscible (2000psi) and miscible (5000psi) conditions increases the recovery up to 12.8% and 22.64% respectively. Recovered oil after inclusion of relative permeability hysteresis demonstrate major corresponding effects of gas retardation, CO2 trapping and improved water permeability. The results show mole fraction of CO2 invading the reservoir remains constant at miscible condition and is not affected by hysteresis. Yet in hysteretic model, the oil recovery factor is slightly declined as the relative permeability to water is improved. The immiscible-hysteretic model incorporates high residual gas/ CO2 gas saturation at the end of each production (imbibition) cycle which increases gradually with historical gas saturation. CO2 mole fractions in both gas and oil phases are intensely decreased due to hysteresis following by decline in CO2 injectivity. Residual CO2 trapped during early cycles, limits the CO2 extent in reservoir and makes the recovery less efficient. In addition to residual saturation, oil composition varies due to different rates of vaporization and diffusion by CO2 as a result of its uneven distribution in reservoir.

We accurately evaluated the efficiency of cyclic CO2 injection in to Bakken tight oil reservoir by incorporating gas-trapping mechanisms in the model. Shortcomings of uncertainties associated with the previous simplified non-hysteretic reservoir models is reduced. Various operational conditions are tested. Our results draw a distinction amongst underlying mechanisms of recovery induced by hysteresis at different miscibility conditions.