bluuebunny/crossref_metadata_2025_split huggingface dataset:
Smart Dual ESP Completion To Develop Stacked Reservoirs
Authors: Alsafadi Ghassan , Siyabi Saud 
Published: March 2019

Abstract
Drilling less wells to produce more oil is the ultimate goal that any oil producing company operator is chasing especially during economic hurdles, in fields with stacked reservoirs, producing long term arrested oil behind casings due to un-ability to commingle two formations at the same time is one of the worldwide production challenges faced oil industry which is always looking for methods that allow producing two reservoirs simultaneously and independently from the same wellbore utilizing one production tubing.
The Smart Dual ESP Completion provide an innovative solution for this common production challenge in fields with stacked reservoirs, this Smart Completion has been tested successfully in one of Alghubar wells in PDO, the results was superior as it reduces the UTC by 74% as well maximize the NPV by approximately 200% (adding new formation and save drilling new dedicated well for each formation)
Alghubar field has a multi–highly- fractured carbonate reservoirs (Natih-A/B, Natih-E and Shuaiba), where the main production is from Natih-E and Shuaiba, the majority of the wells in this field used to be completed with dual gas lift strings in 9 5/8" casing. However due to high operating cost of running an aged gas lift compressor, decision was made to phase it out and start ESP conversion campaign instead. Therefore, producing both Natih-E and Shuaiba formations separately and simultaneously from same wellbore was raised as a key challenge.
The project consists of running Smart Dual ESP in parallel separated by a packer (to separate the two reservoirs) in one completion string with a modified Y-tool (to carry the weight of lower ESP and Packer). They are both producing through one string in the wellbore to surface starting from Y-tool block; both ESP's can be optimized separately and controlled by VSD at the surface, while other completion jewelry were introduced based on the reservoir conditions and well control requirements, the trial supported by detailed simulation analysis using a hybrid model from Prosper and GAP (IPM) to design both ESP's capacity and calculate required motor loads at a different reservoir, wellbore and operation conditions.
This successful trial of smart ESP completion design and the sophisticated installation would open a new horizon in production optimization through reducing the total number of development wells to be drilled in the fields of stacked reservoir from one wellbore. Further value were also obtained such as commercialization of marginal layers through existing wells and utilizing one of the ESP as a backup while waiting for workover in case of break down, subsequently further reduction in UTC and additional project value.
Understanding Mauddud Waterflood Performance in a Heterogeneous Carbonate Reservoir with Surveillance Data and Ensemble of Analytical Tools
Authors: Konwar Lakshi , AlOwainati Ebrahim , AlAnaisis Isa , Nemmawi Nadia , Michael Dowen 
Published: March 2019

Abstract
The Bahrain Oil Field was the first oil discovery in the Gulf Region in 1932 and is now in a mature stage of development. Crestal gas injection in the oil bearing, under saturated, layered and heavily faulted carbonate Mauddud reservoir has continued to be the dominant drive mechanism since 1938. Thirty eight 40 acre 5-spot waterflood patterns were implemented from 2011 to 2012. These patterns were located in both the South East and North West part of the Mauddud reservoir with a maximum injection rate of 80,000 bbl/day. With less than 10% PV water injected as of December 2012, premature water breakthrough was observed in most of the producers. Rapid water breakthrough in Mauddud A (Ba) is attributed to presence of high permeability vugs and layers resulting in water cycling and poor sweep in the matrix leaving bypassed oil. Following recommendations from the 2013 partner Peer Assist, the South East and North West waterfloods have been converted from pattern to peripheral with downdip wells providing water injection. Peripheral re-alignment has arrested the production decline, reduced water cut and stabilized production.
Surveillance data such as bottomhole pressure data, production logs, reservoir saturation logs, temperature logs and tracer data form the basis of understanding waterflood performance. Additionally, an array of analytical tools were used for diagnosis and analysis. Amongst the diagnostic tools, the Y- function helped to understand water cycling and sweep; the modified-Hall plot assisted in understanding the high-permeability channel or lack thereof and the water-oil-ratio (WOR) provided the clue on fluid displacement. Additional plots such as the "X" plot, decline curve, Cobb plot, pore volume injected vs. recovery, Jordan plot, and Stagg's plot were generated to gain insight on the waterflood.
Based on the waterflood analysis, a field study was initiated in December 2016 by shutting more than 80% of water injection followed by complete shut-in in September 2017. The purpose was to reduce the water cut, improve production taking advantage of gravity drainage effect of gas injectors located up dip of waterflood areas. The implementation of water injection shut-in is still ongoing in the Bahrain Field and pressure/production performance is being closely monitored. Improved production performance is observed following water injection shut-in.
This study underscores the importance of modern analytical tools to diagnose and analyze waterflood performance. This understanding also paves the way for much improved learning to take appropriate actions and help devise long-term reservoir management strategy.
Turnaround Inspections Performance Measurement Tool
Authors: Cankara Ilker , Al-Azmi Meshaal 
Published: March 2019

Abstract
Turnaround Inspections, or alternatively called Testing and Inspection (T&I) activities are critically important for the integrity of oil and gas facilities, and if not planned and executed properly, can easily lead to catastrophic failures that may possibly result in injuries, fatalities, property damage, and production losses. Measuring the performance of the teams planning and conducting T&Is, and feeding the measurement findings into the existing plans to achieve continuous improvement, is key to the success of these operations posing high risk. This paper provides detailed information on the structure, design criteria, applicability, and benefits of a T&I Performance measurement tool, developed for a hydrocarbon producing department running several gas oil separation, gas compression and utility plants, and continuously performing T&Is of various magnitudes, based on annual equipment inspection schedules. During the design and development stage, several expectations from Operational Excellence Program, Safety Management System, and Corporate Maintenance Council, were incorporated into the tool. The mentioned alignment with various management systems strengthens the measurement coverage, and if used properly, the tool can bridge multiple gaps identified in various programs. The tool provides a single dashboard "T&I KPI" in the form of a composite index, expressed with four (4) major components, which are namely, HSE (Health, Safety and Environment), Cost& Profitability, Reliability, and Effectiveness. These major components are further broken down to planning and executional success factors, obtained from the actual worksite data and planning compliance checklists. Accidents recorded, availability of job safety analysis, confined space, scaffold, and critical lift plans, compliance to corporate requirements prior to execution of the work, work quality, scheduling performance, and budgetary discipline are among the success factors that feed into the performance readiness and execution measurement calculations. The tool can be utilized for T&I activities governed by an annual schedule, a set of critical equipment to be opened up during planned/unplanned shutdowns, or for a multi-component unit with its associated equipment to be tested and inspected under a single scope, such as a gas compressor system. It drives actions as different aspects of the T&I activities are reviewed with a solid scoring methodology that clearly indicates the areas of improvement, which can then be addressed with corrective actions to prevent reoccurrence. Continuous and consistent utilization of the tool can lead to reduction in the accident frequencies, T&I durations, and outages of critical equipment, vessels, and storage tanks, which could possibly impact plant output rates.
Maximizing the Use of Rock Mechanical Data through Empirical Correlation and Data-Driven Analytics
Authors: Khan Khaqan , Almarri Misfer , Al-Qahtani Adel , Syed Shujath Ali , Negara Ardiansyah , Jin Guodong 
Published: March 2019

Abstract
Rock mechanical properties are required as an input in many petroleum engineering applications, such as borehole stability analysis, hydraulic fracturing design, and sand production prediction. Their determination is commonly from various laboratory testing performed on subsurface rock samples. Due to the scarcity of reservoir samples and test cost, rock mechanical data are always very limited. Therefore, empirical correlations are very often used to estimate the mechanical properties from downhole logging measurements. Alternatively, the data-driven analytics techniques have been developed for predicting rock properties from other formation properties that can be determined directly from logs.
This paper presents a study of developing correlation equations and data-driven models that are used to predict the unconfined compressive strength (UCS) from logging data. Various rock mechanical tests including UCS, single- and multi-stage triaxial tests are performed on sandstone samples from three wells in one region. UCS values are obtained either from the UCS testing directly or from the Mohr-Coulomb failure analysis indirectly. Rock properties, such as mineralogy, porosity, grain and bulk density, ultrasonic wave velocities, are measured for each tested sample, which are used to build the correlations and data-driven analytical models for predicting UCS. Results shows that the empirical correlations are not universal and often cannot be used without some modifications, while the data-driven model is more generalized in application. In addition, data quality is very crucial for building correlations or predictive models.
Hydrajet-Based Fracturing Treatment in Unconventional Wells
Authors: Surjaatmadja Jim B. 
Published: March 2019

Abstract
The success of resource shale development has drawn much attention to develop new technologies to economize the extensive fracturing treatments required to make commercial wells. While a single planar hydraulic fracture is the objective in conventional wells, generating a complex fracturing network is commonly the goal when fracturing unconventional wells. Therefore, in shale formations, it is required to establish connectivity to natural fractures and beddings to generate large Stimulated Reservoir Volume (SRV). Two main staged fracturing techniques have been implemented to complete horizontal wells drilled in the challenging unconventional reservoirs: plug-and-perf and sliding sleeves. This paper presents a technique for effective fracture stimulation, including hydrajetting for fracture initiation, then continuous injection for fracture propagation.
Hydrajetting is used to place singular or dual miniholes of approximately 2-in. ID and 2 ft penetration depth to bypass the near wellbore stress field and focus the energy on generating SRV at a distance away from the disturbed near wellbore stress field (due to drilling effects). The procedure involves two steps: hydrajetting at a given depth using coiled tubing equipped with a gravity-oriented jetting tool, and then fracturing by pumping through both the annulus and the jetting tool. Large miniholes offer minimizing the energy loss created by conventional perforations, avoiding tortuous path generation, minimizing possibilities for near wellbore screen-out, and generating complex fracture networks.
This paper discusses the unique mechanics of the new procedure aimed at creating large SRV in shale formations. The new technique is fairly easy to implement and the beneficial impact could be substantial. The technique and resulting benefits in fracture stimulation of shale reservoirs will be presented.
Predicting and Detecting Equipment Malfunctions using Machine Learning
Authors: Bangert Patrick 
Published: March 2019

Abstract
Condition Monitoring usually analyzes each tag individually using limit values provided by human experts. This results in false alarms and unhealthy conditions that are not alarmed. Using machine learning techniques, all tags on a piece of equipment, such as gas and steam turbines, compressors, pumps, valves, heat exchangers and so on, can be analyzed as a single coherent whole to draw conclusions about its current state of health. A mathematical model of the relevant tag is learned using the other tags of the same equipment. This model represents the equipment as a whole and its behavior when it is operating as it should as only data from known healthy operations are used for learning. The computed value is compared to the measured value. If they agree, the current state is healthy. If they do not, an alarm is released, and a maintenance activity must follow. This method is proven to be far more successful than standard condition monitoring in preventing false alarms and alarming unhealthy states.
Optimization of Energy Recovery from Geothermal Reservoirs Undergoing Re-Injection: Conceptual Application in Saudi Arabia
Authors: Santoso Ryan , Hoteit Hussein , Vahrenkamp Volker 
Published: March 2019

Abstract
The tectonic setting of Saudi Arabia enriches the country with significant geothermal resources, such as those in Al-Lith and Jizan in the southwestern area. Recently, there has been interest to explore the geothermal potential to diversify the country's energy-mix, which is driven by the Kingdom's Vision 2030. One key challenge in geothermal systems is in their low efficiency compared to traditional hydrocarbon-fired plants. This inefficiency is related to the thermal flow behavior in the subsurface and to the energy conversion technology at the surface. In this study, we provide a workflow for feasibility assessment of geothermal reservoir development with potential application in Saudi Arabia.
The proposed workflow is within the Design of Experiment (DoE) framework, which allows conducting numerous simulations with low computational cost. Computations are performed using a proxy modeling approach, which reflects a multidimensional response-surface emerging from the optimization problem. Two steps in the workflow were found to be critical. First, identify and select the most significant uncertainty parameters to focus the design. Second, address the nonlinearity of the problem by filling up any potential gaps within the response space. In this work, two-level folded Plackett-Burman design is used to identify and select the most significant parameters relative to the energy recovery and enthalpy production factors. Three-level Taguchi design is then applied to create a more rigorous proxy model. We used a space-filling technique to address lack of sampling and nonlinearity in the response surface. Monte Carlo simulations are performed, at the final stage, to generate probabilistic forecasts under uncertainties.
The energy recovery factor and the enthalpy production behavior are found to be influenced by the volume of the reservoir, rock permeability and porosity, heterogeneity, well spacing, and fluid production rate. Our Monte Carlo simulations show that, at the Jizan's geothermal conditions, the energy recovery factor is within 12% to 24%, which is encouraging as they are above the typical recovery factor of 10%-17% worldwide.
Effects of Low Versus Standard Pressure Pneumoperitoneum on Renal Syndecan-1 Shedding and VEGF Receptor-2 Expression in Living-donor Nephrectomy: A Randomized Controlled Study
Authors: Aditianingsih Dita , Mochtar Chaidir Arif , Lydia Aida , Siregar Nuryati Chairani , Margyaningsih Nur Ita , Madjid Amir Sjarifuddin , Suwarto Suhendro 
Published: March 2019

Abstract
Background Laparoscopic nephrectomy is a preferable technique for living kidney donation. However, due to increased systemic inflammation, endothelial vascular response, and renal tubular injury, positive-pressure pneumoperitoneum may have an unfavourable effect on the remaining kidney and other distant organs. Early detection of renal injury due to increased intraabdominal pressure induced by pneumoperitoneum is needed. This study aimed to assess the effect of low intraabdominal pressure on kidney injury prevention. Transperitoneal laparoscopic living donor nephrectomy was used as a human model of mild increasing intraabdominal pressure. We compared the effects of low and standard pressure pneumoperitoneum on the shedding of syndecan-1 and vascular endothelial growth factor receptor-2 (VEGFR-2) expression, as these are potential early markers of renal tubular and vascular endothelial cell injury due to a systemic inflammatory response. Methods We conducted a prospective randomized study on 44 patients undergoing laparoscopic donor nephrectomy. Subjects were assigned to standard (12 mmHg) or low-pressure (8 mmHg) groups. Baseline, intraoperative, and postoperative plasma interleukin-6, syndecan-1, and sVEGFR-2 were quantified by ELISA. Syndecan-1 and VEGFR-2 expression was assessed immunohistochemically in renal cortex tissue, and renal tubule and peritubular capillary ultrastructure was examined using electron microscopy. Perioperative hemodynamic changes, end-tidal CO2, serum creatinine, blood urea nitrogen, and urinary KIM-1 were recorded. Results The low-pressure group showed significantly lower intra- and postoperative heart rate, intraoperative plasma IL-6, and sVEGFR-2 levels than the standard pressure group. Although statistically insignificant, plasma syndecan-1 was also lower in the low-pressure group. Proximal tubule syndecan-1 expression was significantly higher in the low-pressure group. VEGFR-2 expression in the proximal and distal tubules and peritubular capillary endothelium was significantly lower in the low-pressure group. The low-pressure group showed better morphological renal tubule and peritubular capillary ultrastructure. Conclusion The low-pressure pneumoperitoneum reduced the shedding of syndecan-1 and VEGFR-2 expression, which are the potential early markers of renal tubular and vascular endothelial injury due to a systemic inflammatory response in laparoscopic nephrectomy. Trial registration ClinicalTrial.gov NCT:03219398 on July 17th 2017.
Prevalence of sleep disorders in Parkinson’s disease patients in Ethiopia
Authors: Melka Dereje , Tafesse Abenet , Bower James H. , Assefa Demeke 
Published: March 2019

Abstract
ABSTRACT
Background: Non motor symptoms (NMS) of Parkinson’s disease (PD) are common and can be more disabling than motor symptoms. Sleep disorders can be seen in up to 98% of patients with Parkinson disease. Poor sleep quality has been associated with poverty and race, and yet there has been no prior report on sleep disorders in those with PD living in sub Saharan Africa. We wished to document the prevalence of sleep disorders in PD patients in Ethiopia.

Methods: We conducted a cross-sectional point prevalence study from July 1 to October 30, 2015 of all patients attending the neurology outpatient department in Tikur Anbessa and Zewuditu Memorial Hospitals, Addis Ababa, Ethiopia. Demographic data, clinical history and physical examination findings were collected from participants using a structured questionnaire. We used the Parkinson’s disease sleep scale version two (PDSS-2) and Epworth Sleepiness Scale (ESS) to assess the sleep symptoms.

Results: Of the 155 patients surveyed, all patients reported some sleep problem. Over 23% of patients had a PDSS score > 30. Hoehn and Yahr score > 3 (OR 6.16; 95% CI 1.59-23.9, p=0.009) and PD symptom duration > 5 yrs (OR 5.11; 95% CI 1.41-18.5, p=.013) associated with a high PDSS-2 score. The median score of ESS was 9 (IQR = 5-12), with 77/155 (49.7%) of the patients having possible or definite excessive daytime somnolence.
Conclusions: In Ethiopian PD patients, the prevalence of those with severe sleep disorders is the highest reported to date. The prevalence of possible/definite EDS is amongst the highest in the world. Further investigation into whether poverty or race explains this finding is needed.

Keywords: Parkinson’s disease, Sleep disorders, Africa, poverty
La tensión entre una espiritualidad desde abajo y una espiritualidad desde arriba. Paradojas de la Exhortación Apostólica Amoris Laetitia
Authors: Basualto Porra Lorena 
Published: March 2019

El artículo busca analizar la paradoja que se puede descubrir en Amoris Laetitia entre una espiritualidad desde abajo y una espiritualidad desde arriba. El Papa Francisco busca romper esta tensión entre el ideal y la realidad a través del desarrollo de una espiritualidad familiar que se encuentra con Dios a partir de las flaquezas, de la incapacidad e incluso de los pecados. Ahora bien, cuando se refiere a temas propios de la moral conyugal y familiar, no puede sino articularlo desde arriba, es decir, desde un ideal determinado que muchas veces prescinde del acercamiento fenomenológico, sin embargo, la paradoja encuentra caminos de solución a través de su concepción de la conciencia y el discernimiento.
La inclusión y la inteligencia espiritual en la Universidad del posconflicto en Colombia
Authors: Cabrales Salazar Omar 
Published: March 2019

El presente artículo de reflexión es fruto de la investigación: La Universidad del Futuro en Colombia, donde se planteó entre otros objetivos realizar un análisis de prospectiva sobre el futuro de la Universidad colombiana en un escenario de diez años, en el marco de tres cuestionamientos esenciales: ¿qué enseñar?, ¿cómo enseñar?, y ¿cuándo enseñar? Desde un enfoque cualitativo, se aplicaron encuestas y entrevistas a docentes y estudiantes de diez universidades públicas y privadas colombianas, en cinco ciudades: Bogotá, Cali, Medellín, Cartagena y Manizales. Como resultado del análisis de dos de las preguntas de la encuesta: 1. ¿En qué áreas deberá enfocarse la Universidad del futuro en Colombia para formar profesionales?, y 2. ¿en cuáles competencias personales deberá formar principalmente la Universidad del futuro? Se argumenta sobre la necesidad de implementar una formación en inteligencia emocional, así mismo, de crear una Universidad más incluyente que abra sus espacios a la variedad de agentes que saldrán de la esfera del conflicto para incorporarse a la sociedad civil y de la apertura hacia la tolerancia que tendrá que llevar a cabo. En tal sentido, se sugiere la incorporación de la inteligencia intrapersonal, emocional y espiritual como una posibilidad de desarrollo de las dimensiones trascendentes de sus estudiantes, sin importar su filiación religiosa.