bluuebunny/crossref_metadata_2025_split huggingface dataset:
AVALIAÇÃO INSTITUCIONAL: uma análise de indicadores de desempenho institucional em uma IFES
Authors: Erasmo Eduardo Andrea Lemus , Duarte Michelle M. Semiguen L. T. , Pires Nunes Enedina Betânia Leite de Lucena , Mendes Rayenne Neres Montelo 
Published: October 2018

Esta pesquisa teve como objetivo analisar os resultados dos indicadores de desempenho institucional considerando as diretrizes estabelecidas e observando as recomendações oriundas dos mecanismos de Avaliação Institucional. Caracteriza-se como exploratória e descritiva e levantamento bibliográfico e documental, com abordagem quali-quantitativa desenvolvida a partir da análise de resultados de indicadores institucionais dos anos de 2016 e 2017, associados, especialmente, ao Eixo 3 – Políticas Acadêmicas, do Sistema Nacional de Avaliação Superior - Sinaes. Os resultados e análises apresentados têm a sua aplicabilidade e relevância institucional, no sentido de apoiar a implementação de estratégias e ações para o desenvolvimento e planejamento institucional da Universidade Federal do Tocantins.

PALAVRAS-CHAVE: Avaliação Institucional; Indicadores de desempenho; Sinaes.

ABSTRACT
This study aimed to analyze the results of the institutional performance indicators considering the established guidelines and observing the recommendations from the mechanisms of Institutional Evaluation. It is characterized as descriptive and exploratory, with bibliographical and documental survey, using an quali-quantitative approach developed from the analysis of the results of institutional indicators of year 2016 and 2017, associated, in particular, with the axis 3 - Políticas Acadêmicas, do Sistema Nacional de Avaliação Superior – Sinaes (Academic Policies of the National System of Higher Assessment). The analyses and results presented have the applicability and an institutional relevance, in order to support the implementation of strategies and actions for the development and institutional planning at the Federal University of Tocantins.

KEYWORDS: Institutional Assessment; Performance indicators; Sinaes.

RESUMEN
Esta investigación tuvo como objetivo analizar los resultados de los indicadores de desempeño institucional considerando las directrices establecidas y observando las recomendaciones oriundas de los mecanismos de Evaluación Institucional. Se caracteriza como exploratoria, descriptiva, levantamiento bibliográfico y documental, con abordaje cualitativito-cuantitativo desarrollada a partir del análisis de resultados de indicadores institucionales de los años 2016 y 2017, asociados, especialmente al Eje 3 – Políticas Académicas, del Sistema Nacional de Evaluación Superior – SINAES. Los resultados y análisis presentados tienen su aplicabilidad y relevancia institucional, en el sentido de apoyar la implementación de estrategias y acciones para el desarrollo y planeación institucional de la Universidad Federal de Tocantins.

PALABRAS CLAVE: Evaluación Institucional; Indicadores de desempeño; Sinaes.
Argentina’s Shale Play is Beginning To Live up to Expectations
Authors: Rassenfoss Stephen 
Published: October 2018

The Vaca Muerta has gone “from a great opportunity to a fact.” The fact is that the giant shale formation is beginning to deliver on high expectations, according to GermÁn Macchi, Argentine country manager for PlusPetrol.
Recent test wells the company drilled there “were better than the upper case,” producing more and richer gas. He was one of nine operators who reported equally strong results at a recent update meeting on the Vaca Muerta in Houston put on by the IAGP—the Spanish acronym for the Argentine Institute of Gas and Oil.
Two years ago when the group representing Argentina’s oil and gas industry held a similar day-long gathering, the talks focused on the formation’s huge potential because production was sparse. This time it distributed a map showing a number of blocks with pilot projects in progress and a growing number with commercial development. The fact is the rock is productive.
Now operators have moved on to worrying about the need for more rigs, roads, pipelines, water, and sand. With promising results and high prices paid for oil and gas—which sells for a subsidized price—they see problems ahead.
The equipment available for drilling and completions “needs to improve significantly,” said Javier Gutierrez, global operations manager for Tecpetrol. If not, “new operators coming into the Vaca Muerta will stretch those resources to the breaking point.”
Those in the packed room heard a message over and over, the rock is really productive, but: “It will take many other ingredients than the rock to make it a global super basin,” said Ed Kruijs, Shell technical manager, Argentina.
They were speaking to service companies who were asked to be ready to expand and government officials who will need to support the regulations and construction needed to sustain a decades-long effort to develop the formation. The cost of drilling a well there is down by 50% or more, but it is lagging behind the costs of the Permian Basin, where there have been similar reductions from a lower base cost.
“We are in a position within our company where we are competing for capital,” said James Blaine, project executive for international projects for ExxonMobil, adding that while the cost of the Argentine operations run by its XTO Energy division are high compared with the Permian, “these are early days.”
“We do see a path to success. The question is, how fast will we get there?” Blaine said.
A big reason for the hopeful tone has been government policy changes loosening regulations on money and equipment flowing in and out of Argentina.
For example, the country eliminated a rule discouraging imports of used equipment by charging the same import duty it would on higher-value new machinery. An executive with an oil tools rental company asked about changing a rule that prevents it from exporting worn tools back to its shops in the US for repairs it cannot do in Argentina.
Machine Learning Overcomes Challenges of Selecting Locations for Infill Wells
Authors: Wilson Adam 
Published: October 2018

This article, written by Special Publications Editor Adam Wilson, contains highlights of paper SPE 190101, “Infill-Well Location-Selection Procedures in Lost Hills Using Machine Learning,” by T.H. Kim, SPE, D.J. Crane, and E.F. Grijalva, SPE, Chevron, prepared for the 2018 SPE Western Regional Meeting, Garden Grove, California, USA, 22–27 April. The paper has not been peer reviewed.
For most conventional reservoirs, numerical simulation is successful in forecasting and extracting valuable information regarding optimal locations for new wells. The results of numerical simulations for the Lost Hills field, however, were not successful because of the special characteristics of its diatomite reservoirs—low permeability but high porosity, weak rock strength, and strong imbibition. Machine learning (ML) has been considered because it does not require specific physical models but can provide good estimations with enough data.
Introduction
The Lost Hills field is approximately 45 miles northwest of Bakersfield, California, USA. It was discovered in 1910, and hydraulic fracturing was introduced in the late 1970s. Waterflooding was introduced in 1992 and has become the main production method. The main reservoir rock type is diatomite, which is formed by the accumulation of diatoms, single-cell organisms. The aver-age pay thickness is approximately 800 to 1,000 ft, and depth to the reservoir base is approximately 2,000 ft. The estimated original oil in place is more than 2 billion bbl.
ML Algorithms and Voronoi Diagram
K-Means Clustering. K-means clustering is one type of unsupervised learning algorithm. As opposed to supervised algorithms, unsupervised learning algorithms do not need answers supplied. K-means clustering algorithms identify the members of each cluster by iterating the following steps:
Generate the centroid of each of the clusters randomly. The number of clusters, K, is a user input.
Each data point is assigned to its nearest centroid so that K clusters are created.
The new centroid of each cluster is updated so that the Euclidian distances to the centroid are minimized.
Repeat Steps 2 and 3 until convergence has been reached.
Support Vector Machine (SVM). SVM is a supervised ML algorithm. For supervised learning algorithms, the answers must be supplied to train and build a predictive model. SVM has two main applications, classification and regression, and classification is used in this study.
SVM builds a hyperplane or set of hyperplanes that separate data into groups (classification) or form a regression line; a hyperplane is a subspace of one dimension less than its ambient space (e.g., a plane in 3D space). Fig. 1 shows an example of classification in 2D space. The red line is a hyperplane set to have the maximum gap between two classes. Data vectors in circles are borderline members and are called support vectors. When building a hyperplane is difficult, data are mapped into a higher-dimensional space to facilitate finding a hyperplane.
Dynamic Steam-Trap-Control Simulation Technique: Formulation, Implementation, and Performance Analysis
Authors: Heidari M.. , Nghiem Long X. 
Published: October 2018

Summary
Steam-trap subcool is a technique that is used to maintain the energy efficiency of the steam-assisted-gravity-drainage (SAGD) process by most heavy-oil producers in Canada. The concept is rather simple (i.e., create a liquid pool around the production well to prevent steam from escaping from the steam chamber into the production well). A numerical steam trap based on a thermodynamic approach was implemented by Edmunds (2000), and it has been used in simulations with different types of wellbore models in commercial codes. In this approach, a thermodynamic relationship is solved as a well-residual equation to guarantee that the bottomhole temperature (BHT) is less than the saturation temperature of water at the hottest location along the wellbore. The location of the hottest spot along the wellbore is static in time. Steam trap is a dynamic process, and inflow temperatures can vary significantly along the wellbore according to the local fluid and rock properties along the well. It is highly possible that the location of the hottest spot along the well changes frequently with time during the SAGD operation.
In this study, the simulation of a dynamic steam-trap-control technique is provided. The location of the hottest spot along the wellbore is scanned at every timestep. Severe numerical instabilities are observed when the thermodynamic approach is used. A new constraint based on the total production rate at reservoir condition is introduced. Details of the mathematical formulation and the numerical behavior of the new method are discussed in this paper. Several real field models with different wellbore designs (multiple tubing strings) are simulated, and the results of the new approach are compared with the thermodynamic approach. Simulation results show that the numerical performance of this new approach is significantly more stable. We also compared the run time of simulation between cases with new well constraint and thermodynamic steam-trap control, and results show a significant improvement in simulation run time.
Improving Casing Integrity With Induction Brazing of Casing Connections
Authors: Ernens D.. , Hariharan H.. , van Haaften W. M. , Pasaribu H. R. , Jabs M.. , McKim R. N. 
Published: October 2018

SummaryBrazing technology allows metallurgical joining of dissimilar materials using a filler material. In this paper, brazing technology applied to casing connections is presented as an enhancement of existing (premium) connections and/or a replacement of metal/metal seals. The initial application was triggered by challenges with mechanical and pressure integrity after the expansion of casing connections. Creating a strong bond between the pin and the box could resolve this and remove the need for a metal/metal seal. Brazing was selected because of the combination of ductility and high bond strength and the relatively fast process to create the bond. The brazing process or the temperature/torque/time (TTT) process is performed using regular casing connections, a filler material deposited by flame spray and a flux. Two processes were developed, one for expandable (VM 50) grade material and one for quenched and tempered grade material. A rig-ready (Class 1, Division 1) prototype brazing system was developed consisting of an induction coil as the heat source, an environmental chamber to shield the hot work, and a modified power tong to provide torque. The results of a series of brazing trials on 8⅝- and 9⅝-in.-casing connections are presented. The brazed connections were subsequently capped, end-pressure tested, expanded (when applicable), and load cycled. It is concluded that both processes produced leak-tight casing connectors before and after expansion (when applicable), as shown by full-scale tests.
Comparative Study of Oil-Dilution Capability of Dimethyl Ether and Hexane as Steam Additives for Steam-Assisted Gravity Drainage
Authors: Baek Kwang Hoon , Sheng Kai , Argüelles-Vivas Francisco J. , Okuno Ryosuke 
Published: October 2018

Summary
Dimethyl ether (DME) was investigated as a potential additive to steam to improve steam-assisted gravity drainage (SAGD) in a previous simulation study. The main objective of this research is to compare DME with n-hexane in terms of the capability of viscosity reduction for Athabasca bitumen. In addition, new experimental data are presented for bubblepoint pressures, densities, and viscosities of Athabasca bitumen and its mixtures with DME and n-hexane.
Results show that DME results in slightly higher viscosity than n-hexane when they are mixed with the same Athabasca bitumen at a given pressure, temperature, and molar concentration. For example, the equimolar mixture of DME with Athabasca bitumen is 79 cp, and that of n-hexane with the same bitumen is 49 cp at 328 K and 60 bar. However, the two solvents are equivalent as diluent at temperatures higher than 380 K. For example, the difference is approximately 1 cp at 382 K and 35 bar between the equimolar mixture of Athabasca bitumen with DME and that with n-hexane.
The viscosity data measured for bitumen/n-hexane mixtures and bitumen/DME mixtures in this research were correlated with three different viscosity models: a modified Arrhenius model, the power-law model, and the Walther (1931) model. The viscosity data were well-correlated with the modified Arrhenius model, but not with the original Arrhenius (log-linear mixing) rule. The modified Arrhenius model can be used directly with a commercial simulator.
Liquid/liquid separation for solvent/bitumen mixtures, which occurred for n-butane/Athabasca bitumen in Gao et al. (2017), was not observed for any of the DME/bitumen and n-hexane/bitumen mixtures in this research. The highest solvent concentration in this study was 80 mol% DME for the DME/bitumen system and 92 mol% n-hexane for the n-hexane/bitumen system.
Development and Application of a Fully Implicitly Coupled Wellbore/Reservoir Simulator To Characterize the Transient Liquid Loading in Horizontal Gas Wells
Authors: Tang Hewei , Rashid Hasan A.. , Killough John 
Published: October 2018

Summary
Liquid loading is a challenging issue in most mature gas fields. The dynamic interaction between wellbore and reservoir when liquid loading happens cannot be comprehensively simulated by a single wellbore simulator or a single reservoir simulator. In this paper, we develop a fully implicitly coupled wellbore/reservoir model to characterize the flow transients in liquid-loaded horizontal gas wells.
We fully couple a wellbore model with an in-house reservoir simulator based on the control-volume finite-difference method. Wellbore transient material-balance equations and mixture momentum-balance equations are solved simultaneously with the reservoir equations to obtain pressure, mixture velocity, and phase holdup in each wellbore segment. Also, we propose a modified drift-flux model that is capable of predicting the flow-regime transition for different pipe inclinations from vertical to horizontal. The modified drift-flux model is integrated in the coupled wellbore/reservoir simulator to characterize the two-phase flow in horizontal wellbores. We validate the coupled wellbore/reservoir model with a commercial multisegment wellbore (MSW)/reservoir simulator. The revised drift-flux formulation not only matches a commercial simulator in production forecast and wellbore pressure, but also predicts the subsequent unstable liquid production caused by flow-regime transitions. For a synthetic field-scale case, the new model predicts gas production that lasts 23 days longer than the prediction of a commercial simulator.
This paper extends the capability of a fully implicitly coupled wellbore/reservoir simulator to simulate the transient liquid-loading phenomenon. The model can serve as a promising tool for gasfield development.
Tunnel-Length Modeling for Coiled-Tubing-Acid-Tunneling Stimulation in Carbonate Reservoirs
Authors: Livescu Silviu , Craig Steven , Aitken Bill 
Published: October 2018

Summary
A coiled-tubing (CT)-acid-tunneling-stimulation technique has been successfully applied in the preceding 15 years on limestone and dolomite reservoirs around the world (the Middle East, southeast Asia, North America, South America, and Europe). Several case histories were presented in the past showing that this technique might bring significant benefits over other carbonate-stimulation methods in openhole wells. In this paper, the parameters affecting the predicted and achieved tunnel lengths are discussed for the first time.
The acid-tunneling technique consists of pumping hydrochloric acid (HCl) through conventional CT and a bottomhole assembly (BHA) with jetting nozzles to create (without drilling) stable drainage holes (tunnels) into the reservoir pay zone. The BHA also includes a special kickoff tool, with two pressure-activated bending joints, that controls the tunnel-creation direction. The acid that is not consumed during the main tunneling process leaks into the reservoir rock, creating wormholes that improve the connectivity between the reservoir and the wellbore and positively influence well production. This acid-tunneling technique can potentially create numerous tunnels with different depths. The optimization of the tunnel-creation-depth selection is made by production-software simulation using such critical information as the well parameters (trajectory and size), available logs (image, resistivity, caliper, drilling), and past reservoir information.
The results from many field case histories involving the CT acid-tunneling technique from around the world were presented previously. However, many questions remain unanswered regarding the actual downhole tunnel-initiation/creation process. In this study, a detailed discussion of acid-tunneling modeling is included to answer some of those questions. The parameters affecting the predicted tunnel lengths and the parameters that could be monitored or adjusted to create the tunnels smoothly are discussed.
This paper describes the CT acid-tunneling technology and discusses some of the most important questions regarding downhole CT acid-tunneling creation. The acid-tunneling-technique performance and benefits confirmed during field operations are presented.
Darcy-Scale Simulation of Boundary-Condition Effects During Capillary-Dominated Flow in High-Permeability Systems
Authors: Andersen Pål Ø. , Brattekås Bergit , Nødland Oddbjørn , Lohne Arild , Føyen Tore L. , Fernø Martin A. 
Published: October 2018

Summary
We present numerical interpretations of two experimental sets of spontaneous-imbibition tests with combined cocurrent/countercurrent flow in high-permeability, unconsolidated sandpacks. The experiments were conducted using the two-ends-open free-spontaneous-imbibition (TEOFSI) boundary condition, in which one end face was in contact with the wetting (W) phase and the other with the nonwetting (NW) phase. The simulations quantified the impact from boundary-condition effects during capillary imbibition in the low-capillary sandpacks; the flow resistance in the outlet filter controlled imbibition rates, end recovery, and countercurrent production in tests with high NW-phase viscosity. A hydrostatic water column of a few centimeters at the W-phase end face also affected the imbibition process. Numerical and analytical solutions provided insight into when such boundary effects become important. In particular, the observed linear recovery with time and variations in time scale could not be explained by conventional modeling, but were captured by incorporating a thin, low-permeability filter into the models. For high-viscosity NW-phase tests with a low-permeability filter, countercurrent production is strongly enhanced and controlled by the capillary backpressure (CBP).
System Run Life Improvement for Rod Driven PCP in High Deviation Well
Authors: Khadav Sandeep , Agarwal Shubham , Kumar Piyush , Pandey Nimish , Parasher Arunabh , Kumar Sanjeev , Agarwal Vinay , Tiwari Shobhit 
Published: October 2018

Abstract
Bhagyam is a shallow onshore field in the northwestern region of India developed by Cairn Oil & Gas, a vertical of Vedanta Limited in two different phases with over 106 oil-producers with deviations as high as 70° and Dog Leg Severity (DLS) up to 7 deg/30m. Rod driven Progressive Cavity Pumps (PCP) were selected as the primary mode of artificial lift. The produced fluid properties which included high wax content and variable fluid viscosity ranging up to 250 cP were the main drivers in the selection of PCPs. A total of 250 unique installations of PCP systems have been completed in over 100 wells. These systems have accumulated a cumulative run-time of over 150,000 days over a total period of more than 2550 days from first installation, with an average tubing-pump system run-life of 600 days.
A major disadvantage of using a rod driven artificial lift system is metal to metal wear between rod and the tubing during operation. This metal wear in rod and tubing results in string failure, increasing costly well interventions and increased system downtime. This paper will demonstrate through specific case studies how pump operating parameters and well design were optimized over time to reduce well interventions and operating expenditures (OPEX).
A centralized data base with real time data configured with a predictive analytical model and automated performance analyzer have enhanced PCP monitoring and troubleshooting. Predictive modelling has improved preventative maintenance such as preemptive rod change outs which greatly reduced the number of rod failures increasing system uptime. In conjunction with joint industry program, detailed root-cause analysis supported with Dismantle Inspection and Failure Analysis (DIFA) laid the foundation for operational and design improvements in PCP operated wells.
Some of the recent improvements employed in system design for PCP operated wells are: Installation of through tubing PCP on an insertable anchor/pump sitting nippleInstallation of packer with completion stringUse of peened rods with molded guidesSnap-on and spin thru guided rodsInstallation of externally flushed hollow rod stringReplacement of conventional vam top tubing with boronized tubingInstallation of high volume PCPs.