bluuebunny/crossref_metadata_2025_split huggingface dataset:
Computational Model of Heat Transfer in ESP System for Deviated Wells
Authors: Galvão H. L. , Oliva G. B. , dos Santos D. P. , Maitelli A. L. , Costa R. O. , Maitelli C. W. 
Published: May 2015

Abstract
Estimation of temperature effects on wells with artificial lift by Electric Submersible Pump (ESP) is necessary because heat transfer may interfere with fluid characteristics, motor behavior, cables and pump, affecting the whole system. This work presents and describes a computational model of heat transfer in ESP systems for multiphase flow in deviated wells.
The methodology adopted in this work considered geothermal gradient and the heat transfer between motor and production fluids. The geothermal gradient represents how temperature increases inside the well as the true vertical depth increases. For deviated wells, the well is divided by sections and temperature increase at each section is calculated as a function of its true vertical depth and the geothermal gradient. In the transfer of heat between motor and production fluids, calculated changes in motor and fluid temperature occur mostly by forced convection on account of high flow rates available in this artificial lift method.
The computational model was implemented in a program developed to simulate ESP system behavior. To validate developed modeling, results obtained through simulation of vertical wells were compared with field data obtained from wells equipped with bottom-hole sensors. These comparisons showed that calculated temperature values were similar to those obtained from a field data, implying satisfactory results. Deviated wells with ESP system were simulated and the results were also evaluated. Therefore, through analysis of the obtained results for thermal calculation in ESP systems, it is possible to verify if the equipment are working according to their specification, especially those related to the electrical system such as cable and motor.
In order to increase the ESP system efficiency, the results obtained through this work are useful for the development of studies focused on reducing harmful effects caused by the high temperatures present in this artificial lift method.
Well Performance and Production Optimization Through the Use of ESPs as Artificial Lift Method
Authors: Hartenbach Guilherme , Magalhães João , Belsvik Yngve , Pessoa Rui , Lemos Daniel 
Published: May 2015

Abstract
Peregrino field, a Statoil asset in Campos Basin approximately 85 km (53 miles) offshore from Cabo Frio/Rio de Janeiro state in Brazil, completes 4 years of production in April 2015 with the use of electrical submersible pumps as the primary artificial lift method. The oil in Peregrino is highly viscous, reaching up to 365 cP at reservoir conditions (234 bars and 82 °C), and API gravity varies between 13° and 15° API. The field development is accomplished by two drilling- capable wellhead platforms where produced fluids are transferred to a central moored floating production storage and offloading unit (FPSO) through booster pumps. There are 27 producer wells and 6 injector wells in operation. The field is producing close to 100,000 BPD of oil. In nearly 4 years of operation water cut has reached up to 95% in some of the wells and, within specific water cut range, emulsion has become a reality and a challenging factor for ESP operation.
Despite the shear effect that liquid undergoes in centrifugal pumps and sand control screens, during the field basis of design phase emulsions were not expected to be a big concern. However, some actions like downhole chemical injection were taken in case emulsions developed. Maximum viscosity considered was up to 2 times the oil viscosity at reservoir conditions and simulations showed acceptable pump behavior and production. On the other hand field experience has required simulator adjustments up to 11 times the PVT oil viscosity for water cut in the range of 30% and 60%. Empirical modifiers were obtained from controlled in-house loop tests to contemplate viscosity effects on pump head, flow and break horsepower simulations.
Due to the high emulsion viscosity, which generally leads to production loss and flow instability, the ESP performance has been severely affected. This has been observed as high differential pressure and motor electrical current fluctuations leading to possible fatigue of ESP internal components and production deferment. This paper describes the emulsion issues faced in Peregrino and the challenges to minimize their effects.
The objective of this paper is to describe the performance of the field, status and experience gained with Peregrino production regarding optimization and ESP performance.
Use of ESP Motor Cooling Systems
Authors: Mazzola Ricardo , Colla Miguel , Muñoz Heber , Bruni Marcelo , Teves Ricardo , Oyarzun Raul 
Published: May 2015

Abstract
In the last 5 years, GE Oil&Gas and Panamerican Energy worked on alternatives to produce Wells below perforations. All wells are produced by 3.75″ motor having refrigerating shrouds with very good performance. Today's failure index with this technology is 0.20. Besides the fact this is the simplest way to produce below perforations on vertical wells, having mentioned performance for high temperature and deep wells, it is required to overcome some limitations with this technology: In particular one of the problems that shrouded systems have in small series motors is the length of the equipment. This requires up to 30 meters achieving 100hp for a given rating. In general 4 to 5 motors are needed increasing installation time. Also, shrouds have the limitation on well's having doglegs: sometimes shrouds are lost during installation. Long shrouded equipment installed in small casing could also lead to some pressure drops due to scale deposition, reducing production capabilities.
This paper shows the experience in Pan-American Energy on alternative deployments below perforations having production recirculation tubes named Motor Cooling and Snorkel systems, and some comparative results with shrouded system.
Experience With Inverted ESP for Water Injection in Secondary Recovery Project
Authors: Tarabelli Mauro Luis , Blanco Armando , Oyarzun Raul , Russo Martin , Teves Ricardo 
Published: May 2015

Abstract
This paper presents the implementation of an inverted ESP pumping system for injecting water purposes in YPF SA.
In some fields, where it is not yet available facilities in the surface for water treatment and subsequent injection by mean of a conventional system, it is convenient to use an electric submersible pump installed in the injection well. This can be used for pilot testing in some potential areas to start a secondary recovery project. This well has an aquifer available which meets the technical and legislative conditions to be injected in another layer below. This second layer is of particular interest in starting secondary recovery tests.
Both layers are insulated by mean of a standard packer, locked before the ESP deployment.
In the upper side of the packer, the ESP is installed having instrumentation to monitor the water flow rate injected.
In particular this equipment has, unlike a conventional ESP, a seal and a centrifugal pump placed in the bottom side of the motor. A down-hole sensor is located at the top side where all equipment is hanging from.
This report will show the technical challenges and design criteria experienced by YPF SA and GE Oil & Gas for pump selection, instrumentation, fitting and accessories required for completion
Souring Development Associated with PWRI in a North Sea Field
Authors: Evans Paul , Nederlof Eduard , Richmond Will 
Published: May 2015

Abstract
A North Sea Field has been water flooded with commingled produced and aquifer water since 1997. Low- sulphate source waters were selected for injection in order to mitigate barium sulphate scaling and reservoir souring development. Small volumes of seawater are included in the injection water due to operational reasons, but the average sulphate concentration of the overall injection water does not exceed 20 mg/l. Aquifer and produced water has historically been injected with minimal treatment due to the high permeability of the clastic reservoirs.
Despite the low sulphate concentration of the injection water there has been souring development over field life. The reservoir temperature of 104 F is sufficiently low to allow microbiological activity throughout the reservoir. Microbiological monitoring in the produced fluids indicates the presence of sulphate-reducing bacteria (SRB), but the low sulphate availability limits SRB activity.
The injection water was treated with continuous biocide with the intention of controlling SRB activity within the reservoir, and reservoir souring simulations were carried out to investigate the effectiveness of this treatment. The simulation results indicated that the levels of H2S present in the produced water were consistent with the availability of sulphate in the injection water, and that the biocide treatment was not limiting SRB activity. The continuous biocide treatment was discontinued and no subsequent increase in H2S generation was observed in the field, demonstrating that souring development was sulphate limited.
Offshore IOR/EOR Implementation Through Weight and Footprint Reduction
Authors: Henthorne Lisa , Van Pelt Stephen , Johnson Holly 
Published: May 2015

Abstract
Treating water for injection in an offshore environment has always been challenging. As injection water quality becomes more stringently specified to maximize oil production across a wide range of reservoir geologies, the technical and economic complexity of treating the water dramatically increases. The more stringent treatment can include fine filtration to improve injectivity, specific ion treatment such as sulphate, calcium, magnesium removal to reduce precipitation risks and/or to enable chemical EOR, low salinity treatment for IOR/EOR, and deaeration to very low levels of oxygen to reduce corrosion.
One of the most significant aspects of this added complexity is the inherent weight and footprint of the various unit operations of the water treating facilities that are necessary to achieve rigorous treatment. The weight and footprint of these facilities directly impacts capital costs, which in turn affects the economic viability of greenfield projects and, to an even larger degree, dictates the feasibility of brownfield improvements.
The need for robust, lightweight and compact water treatment technologies for offshore injection has driven innovations in filtration, desalination, softening, sulphate removal, and deaeration. Relative to existing conventional seawater injection facilities composed of media filtration followed by vacuum tower deaeration, the subject innovations achieve an approximate 50 and 90% reduction in footprint and weight, respectively. A number of these technologies have recently undergone pilot and field testing to improve their technology readiness levels prior to full-scale commercialization, and to demonstrate capital costs savings. In addition, operating costs were evaluated. This paper presents the performance results of the pilot and field tests of two of these compact technologies: high production reverse osmosis membranes, and membrane deaeration. In addition to performance results, weight and footprint reductions associated with the technologies are provided to demonstrate the expected savings.
Identifying Chinese Microblog Users With High Suicide Probability Using Internet-Based Profile and Linguistic Features: Classification Model
Authors: Guan Li , Hao Bibo , Cheng Qijin , Yip Paul SF , Zhu Tingshao 
Published: May 2015

BackgroundTraditional offline assessment of suicide probability is time consuming and difficult in convincing at-risk individuals to participate. Identifying individuals with high suicide probability through online social media has an advantage in its efficiency and potential to reach out to hidden individuals, yet little research has been focused on this specific field.ObjectiveThe objective of this study was to apply two classification models, Simple Logistic Regression (SLR) and Random Forest (RF), to examine the feasibility and effectiveness of identifying high suicide possibility microblog users in China through profile and linguistic features extracted from Internet-based data.MethodsThere were nine hundred and nine Chinese microblog users that completed an Internet survey, and those scoring one SD above the mean of the total Suicide Probability Scale (SPS) score, as well as one SD above the mean in each of the four subscale scores in the participant sample were labeled as high-risk individuals, respectively. Profile and linguistic features were fed into two machine learning algorithms (SLR and RF) to train the model that aims to identify high-risk individuals in general suicide probability and in its four dimensions. Models were trained and then tested by 5-fold cross validation; in which both training set and test set were generated under the stratified random sampling rule from the whole sample. There were three classic performance metrics (Precision, Recall, F1 measure) and a specifically defined metric “Screening Efficiency” that were adopted to evaluate model effectiveness.ResultsClassification performance was generally matched between SLR and RF. Given the best performance of the classification models, we were able to retrieve over 70% of the labeled high-risk individuals in overall suicide probability as well as in the four dimensions. Screening Efficiency of most models varied from 1/4 to 1/2. Precision of the models was generally below 30%.ConclusionsIndividuals in China with high suicide probability are recognizable by profile and text-based information from microblogs. Although there is still much space to improve the performance of classification models in the future, this study may shed light on preliminary screening of risky individuals via machine learning algorithms, which can work side-by-side with expert scrutiny to increase efficiency in large-scale-surveillance of suicide probability from online social media.
Participation of various habitat groups in the flora of spring niches in the Ojców National Park (Southern Poland)
Authors: Sołtys-Lelek Anna , Barabasz-Krasny Beata , Różkowski Jacek 
Published: May 2015

Abstract
The paper presents composition of vascular plant species in spring niches in the Ojców National Park (Southern Poland). 111 species of vascular plants, fourteen mosses, two liverworts and one species of ferns were recorded during the first comprehensive study carried out in 2009 and 2010. Plants occurring in these places showed different degrees of association with spring niches. The largest group was represented by accidental krenophytes (74 species), while spring plants - obligatory krenophytes, constituted only a small part of the local flora (5 species). Meadow species of the Molinio-Arrhenatheretea class and forest species of the Querco-Fagetea class, penetrating niche areas from the adjacent areas, were the dominating ones. Plants of aquatic and spring communities were scarce, due to the predominance of small type karst springs. The diversity of vegetation was significantly influenced by habitat factors such as availability of light, humidity or the amount of organic matter in the soil.
Myoxanthus ortizianus (Orchidaceae), a new species from southern Colombia
Authors: Kolanowska Marta , Szlachetko Dariusz L. 
Published: May 2015

Abstract
With over 3000 species, Colombian orchid flora represents one of the richest in the World. The neotropical subtribe Pleurothallidinae is the most diverse, but it is still a poorly recognized Orchidaceae group and numerous new discoveries within national representatives are described every year. An examination of material collected recently in the Colombian department of Putumayo revealed the existence of a new species of Myoxanthus, named M. ortizianus, which is described, illustrated and placed within an identification key for national species of the nominal section of the subgenus Myoxanthus.
Ophrys apifera Huds. (Orchidaceae), a new orchid species to the flora of Poland
Authors: Osiadacz Barbara , Kręciała Mirosław 
Published: May 2015

Abstract
The paper provides data on the first locality of Ophrys apifera Huds. s. str. in Poland. Information about its geographical distribution and ecological features is given. A newly discovered population, found in a worked-out dolomite quarry near Imielin (Silesian Upland), is described and illustrated, as also, O. apifera is compared with O. insectifera L.
Management of Chronic Rhinosinusitis with Nasal Polyps and Coexisting Asthma: A Systematic Review
Authors: Rix Iben , Håkansson Kåre , Larsen Christian Grønhøj , Frendø Martin , von Buchwald Christian 
Published: May 2015

Background Chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) and asthma are strongly associated, and patients suffering from both diseases are often difficult to treat. However, no guidelines about the management of patients with CRS and coexisting asthma exist. Objective The purpose of this systematic review was to evaluate the management of CRSwNP and coexisting asthma. Methods We systematically searched electronic databases and included clinical trials in which the clinical outcomes after medical or surgical treatment of patients with CRSwNP and asthma were assessed. The strength of the evidence for each outcome was graded on the basis of study quality and consistency in findings. Results We included seven trials in which the effect of montelukast, omalizumab, erythromycin, and functional endoscopic sinus surgery (FESS) were studied in 317 adults with CRSwNP and asthma. All the interventions improved the majority of subjective and objective nasal outcomes significantly. However, few studies found significant effects on pulmonary function tests. The strength of the evidence was low overall. Conclusion Both FESS and medical interventions with systemic anti-inflammatory drugs improved nasal outcomes, although their efficacy in relation to the lower airways remains unclear. A low number of studies met inclusion criteria for this systematic review, which emphasizes the need for high-quality trials to explore the treatment of patients with CRSwNP and coexisting asthma.
Role of Wnt Signaling Pathway in Progression of Sinonasal Inverted Papilloma to Squamous Cell Carcinoma
Authors: Jung Yong Gi , Lee Hyun Wook , Kim Myung-Gu , Dhong Hun-Jong , Cho Kyu-Sup , Roh Hwan-Jung 
Published: May 2015

Background Sinonasal inverted papilloma (IP) is one of the most common benign tumors of the sinonasal area and malignant transformation has frequently been reported. However, the exact mechanism of the transition from benign lesion to malignancy is not known. The Wnt signaling pathway involves a network of multiple signaling glycoproteins that are known to play an important role in embryogenesis and carcinogenesis. Objective The purpose of this study was to evaluate the role of the Wnt pathway and signaling proteins in malignant transformation of IP to dysplasia and squamous cell carcinoma. Methods Expression of the Wnt signaling pathway proteins, including Wnt-1, beta-catenin, cyclin D1, and Dishevelled-1 (Dvl-1), were detected by immunohistochemistry by using 3-mm tissue core microarrays that consisted of 115 cores of IP tissue. Each of the IP cores was graded as I (prominent squamous metaplasia), II (inverted pattern), III (dysplasia), or IV (squamous cell carcinoma). The expression pattern of each protein and the correlation between the expression of each target protein and IP grade were evaluated. Results Membranous staining of beta-catenin showed a significant positive correlation with IP grade (ρ = 0.247, p < 0.001), as did staining of cyclin D1 (ρ = 0.365, p < 0.001), which showed a nuclear pattern and staining of Dvl-1 (ρ = 0.380, p < 0.001), which showed a membranous, cytoplasmic, and nuclear pattern. For Dvl-1, a nuclear expression pattern was more frequently observed in grade III and IV IP (p = 0.036). In the case of Wnt-1, cytoplasmic expression was observed; however, it did not show a significant correlation with IP grade (ρ = 0.141, p = 0.130). Conclusions Wnt signaling proteins, including beta-catenin, cyclin D1, and Dvl-1, may play crucial roles in the malignant transformation of IP.
Collecting and Preserving Marine and Freshwater Isopoda (Crustacea: Peracarida)
Authors: Wetzer Regina 
Published: May 2015

Isopoda are the most diverse Crustacea. In order to encourage the study of isopod crustaceans and their use in biodiversity studies, systematics, ecology, physiology and more, one needs to know who the isopods are and where to find them.
This is a short “how to” guide focusing on the free-living marine and freshwater isopods: where they live and how to collect and preserve them. The tools and techniques described here are simple, but invaluable in accessing the natural history of these remarkable creatures.
Recherche psychosociale dans des communautés traditionnelles : analyse de l’expérience du programme de pré-initiation scientifique de l’université de São Paulo
Authors: Bernardo Parodi Svartman , Alessandro de Oliveira dos Santos , Alessandra B. M. Martins , Ricardo Casco , Luís Guilherme Galeão-Silva , Gustavo M. Massola 
Published: May 2015

Cet article présente les résultats et les développements psychosociaux d’une recherche articulée au programme de pré-initiation scientifique à l’université de São Paulo. Le but de cette recherche, réalisée par l’Institut de psychologie, en partenariat avec deux écoles techniques de la région de la vallée du Ribeira (SP), a pour objectif de décrire les projets de tourisme à base communautaire, développés par deux communautés traditionnelles de la région : la communauté quilombola d’Ivaporunduva (communatuté des anciens quilombos ) et la communauté caiçara de Marujá (pêcheurs traditionnels). Nous concluons que le programme de pré-initiation scientifique possède un grand potentiel de renforcement des liens entre les écoles et les communautés. En outre, les recherches effectuées en partenariat avec des communautés et des écoles permettent l’élaboration d’une connaissance sur le territoire, qui peut être fondamentale pour le développement d’expériences d’enracinement, ainsi que pour le mouvement de résistance à la globalisation comme à la mondialisation.
La cartographie comme méthode : pistes pour la pratique d’une recherche-intervention
Authors: Virgínia Kastrup 
Published: May 2015

L’objectif de cet article est d’indiquer quelques pistes qui précisent la spécificité de la méthode de la cartographie, dans le contexte de la recherche-intervention pratiquée au Brésil. Il s’agit d’analyser les effets d’une intervention sur quatre niveaux : chez les participants, chez les chercheurs, sur l’orientation même de la recherche et sur le terrain où elle s’insère. L’article apporte des fragments de deux recherches de terrain sur le processus de production de subjectivité et de cognition inventive. La première a été réalisée dans un atelier de lecture pour enfants pauvres en situation de violence, dans le quartier de São Domingos, de la ville de Niceroi. La seconde recherche, qui avait pour objectif d’étudier comment fonctionne l’attention chez des aveugles au cours de processus de création, a été réalisée dans un atelier de céramique de l’Institut Benjamin Constant, à Rio de Janeiro.