bluuebunny/crossref_metadata_2025 huggingface dataset:
Práticas de higiene em uma feira livre da cidade de Salvador (BA)
Authors: Minnaert Ana Cláudia de Sá Teles , Freitas Maria do Carmo Soares
Published: July 2010

Trata-se de compreender os significados das práticas de higiene dos alimentos em uma feira livre da cidade de Salvador (BA). O estudo etnográfico consegue apreender duas categorias centrais como produção simbólica das práticas higiênicas: o limpo como ordem e o sujo como desordem. Esses códigos culturais fazem correspondências com os estudos de Mary Douglas e Norbert Elias e apresentam especificidades para decifrar um mundo cotidiano em que concepções e práticas de higiene são aspectos normalizados por personagens que compartilham o espaço da feira: feirantes, consumidores, garis e fiscais municipais. O conhecimento técnico-científico e a legislação sanitária são tidos como estranhos ao sistema simbólico dos feirantes. As leis não são efetivas e não têm uma influência importante na construção das práticas higiênicas. As práticas dos fiscais municipais são coercitivas e punitivas e não consideram os valores culturais na formação de novas práticas de higiene.
Reforma psiquiátrica e inclusão social pelo trabalho
Authors: Rodrigues Rúbia Cristina , Marinho Tanimar Pereira Coelho , Amorim Patricia
Published: July 2010

Este estudo busca compreender a relação entre trabalho, adoecimento mental e reabilitação psicossocial a partir da narrativa de pessoas portadoras de transtorno mental e usuárias de substâncias psicoativas sobre o sentido do trabalho. O estudo ocorreu em Centros de Atenção Psicossocial (CAPS) da cidade de Goiânia (GO), do qual participaram oito pessoas adultas e de ambos os sexos, que traziam o trabalho como algo importante em suas vivências. Utiliza-se de metodologia qualitativa e exploratória, por meio da realização de grupo focal. Para o tratamento dos dados, utiliza-se a análise temática. Os resultados apontam os sentidos do trabalho enquanto existencialização e identidade social, autonomia e sociabilidade. Na interface com a saúde mental, o trabalho surge como protetor e/ou adoecedor mental. Os processos de exclusão social dos participantes ocorrem através da dificuldade de acesso à seguridade social relacionada ao trabalho e ao preconceito social vivido na tentativa de ingresso ao mundo do trabalho. Enquanto possibilidade de (re) inserção social, o estudo mostrou que os CAPS têm dificuldades em propor alternativas de inclusão pelo trabalho, apesar da melhoria de vida promovida pelo acompanhamento psicossocial.
Que direito? Trajetórias e percepções dos usuários no processo de acesso a medicamentos por mandados judiciais em Santa Catarina
Authors: Leite Silvana Nair , Mafra Ana Cristina
Published: July 2010

O objetivo do estudo foi analisar as trajetórias dos usuários de Itajaí (SC) que recebem medicamentos via mandados judiciais contra o Estado de Santa Catarina, suas motivações e percepções sobre esta forma de acesso aos medicamentos. A metodologia consistiu de entrevistas semiestruturadas com os solicitantes de medicamentos de Itajaí no ano de 2006. Aceitaram participar dezoito usuários. Nenhum entrevistado sabia que poderia cobrar o medicamento do estado antes de ser avisado pelo médico (39%), Secretaria de Saúde (22%), advogado (11%), amigos ou associações (28%). A análise temática revelou que uma grande categoria, denominada "Não consciência do direito social", é o eixo estruturante de todas as trajetórias e forma pela qual os usuários percebem a construção do processo judicial. Conclui-se que o recebimento atual do benefício não promoveu a conscientização do direito social, pois a forma de condução dos processos não é empoderante, ao contrário, reforça as relações de dependência e a percepção de impotência do usuário.
Integralidade e transdisciplinaridade em equipes multiprofissionais na saúde coletiva
Authors: Severo Silvani Botlender , Seminotti Nedio
Published: July 2010

Este artigo traz uma discussão e reflexão sobre a ativação da integralidade no processo de trabalho das equipes multiprofissionais na saúde coletiva. Alicerçamo-nos na teoria da complexidade de Edgar Morin e na lógica transdisciplinar de Basarab Nicolescu para compreender os paradoxos na ação coletiva dos trabalhadores no desafio de integrar as formações disciplinares com a exigência na prática de processos inter/transdisciplinares. Os trabalhadores encontram dificuldades na reorientação do modelo assistencial na saúde quando sua lógica está centrada na doença.
Discursos sobre comportamento de risco à saúde e a moralização da vida cotidiana
Authors: Bagrichevsky Marcos , Castiel Luis David , Vasconcellos-Silva Paulo Roberto , Estevão Adriana
Published: July 2010

O texto aborda criticamente a polaridade entre discursos sobre estilos de vida saudáveis e sedentarismo no contexto dos novos recursos tecnológicos de busca e disseminação de informações em saúde. Argumenta-se que a racionalidade tecnocientífica contemporânea fez emergir uma "economia das verdades" que, na perspectiva de conduzir a estilos de vida seguros, tem prescrito um ideário normativo de autodisciplina gerador de angústias e de consumo de artefatos agenciadores de gastos calóricos. Na produção hegemônica desses regimes de verdade, o sedentarismo se apresenta como conduta de risco à saúde, equivalendo à falência moral e inaceitável falta de cuidado consigo. Enfatiza-se que a profusão de discursos sobre estilos de vida e risco, tomados como dispositivos biopolíticos imbricados nos processos comunicacionais em saúde, merece foco por suas implicações éticas e políticas. A espetacularização de modos de vida associados ao consumo e a produção de narrativas que influenciam perversamente nossa cultura têm nos distanciado de uma noção de saúde socialmente possível. Discute-se, enfim, a essência reguladora de tais referentes simbólicos na construção de sistemas de conhecimento que vêm (re)definindo o que é ser saudável, normal, doente.
A formação médica e a clínica ampliada: resultados de uma experiência brasileira
Authors: Hafner Maria de Lourdes Marmorato Botta , Moraes Magali Aparecida Alves de , Marvulo Marilda Marques Luciano , Braccialli Luzmarina Aparecida Doretto , Carvalho Maria Helena Ribeiro de , Gomes Romeu
Published: July 2010

Trata-se de um estudo qualitativo que faz parte de uma pesquisa de avaliação de um curso de medicina com o uso de metodologias ativas de ensino-aprendizagem, baseada na triangulação de métodos. O objetivo é avaliar resultados relacionados ao conceito de clínica ampliada. As fontes de informação utilizadas no estudo abrangem dezessete entrevistas semiestruturadas com egressos e uma situação que simulava a prática médica, da qual participaram sete egressos e uma paciente simulada. A análise das informações e a produção dos dados baseiam-se no método de interpretação de sentidos, segundo referencial da hermenêutica-dialética. Os resultados apontam aspectos que fundamentam a clínica ampliada, evidenciados em duas temáticas: a relação médico-paciente e abordagem do paciente. Em termos de conclusão, observa-se que o curso de medicina avaliado se aproxima da formação do médico generalista, humanista, crítico e reflexivo, que pode intervir tanto nos diferentes níveis de atenção de saúde quanto no enfoque individual e coletivo. Conclui-se, ainda, que há limites para a efetivação de uma clínica ampliada nos diversos cenários de saúde.
Humanidades e medicina: razão e sensibilidade na formação médica
Authors: Rios Izabel Cristina
Published: July 2010

No presente artigo, discute-se brevemente o ensino de humanidades na medicina e apresenta-se uma proposta criada no Centro de Desenvolvimento da Educação Médica (CEDEM) da Faculdade de Medicina da Universidade de São Paulo (FMUSP) para a integração dessa área no currículo médico. A integração curricular é uma estratégia de ensino fundamentada na visão sistêmica que envolve ações de amplo alcance educacional. No ensino de humanidades na medicina, são ações que visam à sensibilização das pessoas (para somar, ao escopo técnico, o olhar sobre a condição humana), e ao desenvolvimento de métodos didático-pedagógicos adequados ao seu aprendizado. A proposta de integração curricular constitui-se de seis ações estratégicas, em estados diferentes de desenvolvimento: (1) elaboração dos objetivos terminais da área para a formação do aluno,(2) integração das disciplinas de humanidades do currículo atual, (3) integração dos temas humanísticos em outras disciplinas de acordo com os objetivos terminais, (4) planejamento de cursos de humanidades médicas para docentes, (5) desenvolvimento de sistema de avaliação e acompanhamento da formação humanística,(6) divulgação da área "Humanidades e Medicina".
Controle de infecção oral em pacientes internados: uma abordagem direcionada aos médicos intensivistas e cardiologistas
Authors: Kahn Sérgio , Mangialardo Elen de Saboya , Garcia Carlos Henrique , Namen Fátima Maria , Galan Júnior João , Machado Walter Augusto Soares
Published: July 2010

O objetivo do presente estudo foi verificar o grau de conhecimento médico sobre medicina periodontal e verificar a existência de algum protocolo de controle de infecção da cavidade oral em pacientes internados em hospitais. Para tal, 110 médicos cardiologistas e intensivistas lotados em cinco hospitais no município do Rio de Janeiro foram entrevistados. Dentre os indivíduos, 75,4% afirmaram ter conhecimento sobre o termo medicina periodontal; entretanto, apenas 30% declararam já ter lido algo a respeito. Apenas 2,7% dos médicos possuem o hábito de coletar informações sobre a história odontológica de seus pacientes e 58,2% afirmaram que essa conduta é condicional ao quadro apresentado pelo paciente. Com base nos dados obtidos, pode-se concluir que o conhecimento sobre medicina periodontal e, consequentemente, sobre a importância do controle do biofilme oral na manutenção da saúde sistêmica, apresenta-se pouco difundido entre a classe médica. Verificou-se não haver setor ou pessoa responsável pelo controle de infecção oral dentro dos hospitais avaliados e, consequentemente, a não existência de qualquer protocolo, eficaz ou não, de controle de infecção oral nessas unidades.
Intersetorialidade nas ações de promoção de saúde realizadas pelas equipes de saúde bucal de Curitiba (PR)
Authors: Moretti Andreya Cristina , Teixeira Fabrício Farias , Suss Fabiane Maria Bortoloso , Lawder Juliana Aparecida de Campos , Lima Luciane Silveira Miranda de , Bueno Roberto Eduardo , Moysés Samuel Jorge , Moysés Simone Tetu
Published: July 2010

O objetivo deste estudo foi explorar as ações intersetoriais desenvolvidas pelas equipes de saúde bucal na rede Municipal de Saúde de Curitiba (PR) e analisar a percepção dos gestores locais ligados a estas equipes sobre a intersetorialidade. Utilizou-se um modelo de estudo transversal de metodologia quantitativa e qualitativa, com coleta de dados por meio de um questionário autoaplicável e a técnica do grupo focal. Os resultados mostraram que as maiorias das ações de promoção de saúde realizadas pelas equipes são interdisciplinares e quando há envolvimento de outros setores é na disponibilização de espaços físicos, sem uma perspectiva de ação conjunta e integrada. A percepção dos gestores reitera no conceito as práticas das equipes. Observou-se que a Estratégia da Saúde da Família é facilitadora de ações intersetoriais e que, apesar das dificuldades, a intersetorialidade é uma forma de trabalho desafiadora, mas possível de tornar-se realidade.
Feminização do curso de odontologia da Universidade Estadual de Montes Claros
Authors: Costa Simone de Melo , Durães Sarah Jane Alves , Abreu Mauro Henrique Nogueira Guimarães de
Published: July 2010

Este artigo fundamenta a tese de "feminização" da odontologia através da literatura especializada no tema e concentra na revisão bibliográfica a análise deste fenômeno. Para ilustrar, realizou-se um estudo de caso analisando o número de inscritos no processo seletivo para odontologia na Universidade Estadual de Montes Claros - Unimontes, Brasil, apresentando os selecionados e concluintes, por sexo. A análise refere-se aos anos de 1997 a 2006. O curso desde sua implantação tem apresentado maior porcentagem de mulheres, tanto com relação aos ingressantes e concluintes, como no processo seletivo. O referencial teórico analisado vai ao encontro dos dados empíricos desse estudo de caso, donde se conclui que o fenômeno da feminização também ocorre no curso de odontologia da Unimontes.
Species selection and driven mechanisms jointly generate a large-scale morphological trend in monobathrid crinoids
Authors: Simpson Carl
Published: July 2010

All evolution attributable to natural selection, at any level, is due to a causal covariance between fitness and phenotype. Over macroevolutionary time scales, species selection is one of many possible mechanisms for generating large-scale morphological trends. For species selection to sort morphology, a correlation between morphology and taxonomic diversification rate must be present. Other trend mechanisms (driven mechanisms, e.g., a bias in the direction of speciation) produce a systematic change in the mean phenotype over time. All mechanisms can co-occur. Here I demonstrate (1) an inverse correlation between diversification rate and calyx complexity that demonstrates the effect of species selection on morphology. Genera with simple calyces tend to increase in diversity, whereas genera with complex calyces have a net decrease in diversity; and (2) the presence of a driven trend mechanism in monobathrid crinoids where descendant genera tend to be simpler than their ancestors. The separate effects of these two classes of trend mechanisms can be combined by using the Price's Theorem, which partitions the contribution to the overall change in calyx complexity over time accurately among selection and driven mechanisms. Price's Theorem provides significant conceptual and methodological clarification of the contribution of multiple and interacting hierarchical mechanisms in generating large-scale trends.
Comparison of morphometric techniques for shapes with few homologous landmarks based on machine-learning approaches to biological discrimination
Authors: Bocxlaer Bert Van , Schultheiß Roland
Published: July 2010

Biometric analyses are useful tools for the study of organisms, their phylogenetic affiliation, and the pattern and rate of their evolution. Various morphometric techniques have been developed to analyze morphological variation, but methodological choices are often made arbitrarily because quantitative comparisons are lacking or inconclusive. Here we address morphometric quantification of taxa with few unambiguously identifiable landmarks (<15), utilizing ornamented and unornamented gastropod shells. Support vector machines were applied to evaluate classification performances of landmark (LMA), elliptic Fourier (EFA), and semi-landmark analysis (SLM). This evaluation is based on the discrimination of between-group differences relative to within-group variation, and thus allows comparing how the techniques treat different types of biological information. The results suggest that EFA performs slightly better than SLM (and certainly LMA) in discerning a priori identified taxa with unornamented shells, but that SLM is significantly superior to other techniques for ornamented shells. Alignment and homology problems may cause the subtle variations in ornamentation to become blurred as noise in EFA, even though EFA is often cited to be able to deal with complex shapes. Performance of LMA depends entirely on how accurately the structure can be covered with landmarks. Guidelines in choosing a morphometric technique in diverse cases are provided.
Quantitative comparisons and models of time-averaging in bivalve and brachiopod shell accumulations
Authors: Krause Richard A. , Barbour Susan L. , Kowalewski Michał , Kaufman Darrell S. , Romanek Christopher S. , Simões Marcello G. , Wehmiller John F.
Published: July 2010

The variation in time-averaging between different types of marine skeletal accumulations within a depositional system is not well understood. Here we provide quantitative data on the magnitude of time-averaging and the age structure of the sub-fossil record of two species with divergent physical and ecological characteristics, the brachiopodBouchardia roseaand the bivalveSemele casali.Material was collected from two sites on a mixed carbonate-siliciclastic shelf off the coast of Brazil where both species are dominant components of the local fauna.

Individual shells (n= 178) were dated using amino acid racemization (aspartic acid) calibrated with 24 AMS radiocarbon dates. Shell ages range from modern to 8118 yearsb.p.for brachiopods, and modern to 4437 years for bivalves. Significant differences in the shape and central tendency of age-frequency distributions are apparent between each sample. Such differences in time-averaging magnitude confirm the assumption that taphonomic processes are subject to stochastic variation at all spatial and temporal scales. Despite these differences, each sample is temporally incomplete at centennial resolution and three of the four samples have similar right-skewed age-frequency distributions. Simulations of temporal completeness indicate that samples of both species from the shallow site are consistent with a more strongly right-skewed and less-complete age-frequency distribution than those from the deep site.

We conclude that intrinsic characteristics of each species exert less control on the time-averaging signature of these samples than do extrinsic factors such as variation in rates of sedimentation and taphonomic destruction. This suggests that brachiopod-dominated and bivalve-dominated shell accumulations may be more similar in temporal resolution than previously thought, and that the temporal resolution of multi-taxic shell accumulations may depend more on site-to-site differences than on the intrinsic properties of the constituent organisms.
Seasonality, the latitudinal gradient of diversity, and Eocene insects
Authors: Archibald S. Bruce , Bossert William H. , Greenwood David R. , Farrell Brian D.
Published: July 2010

In the modern world, biotic diversity is typically higher in low-latitude tropical regions where there is abundant insolation (light and heat) and low thermal seasonality. Because these factors broadly covary with latitude, separating their possible effects on species diversity is difficult. The Eocene was a much more equable world, however, with low temperature seasonality extending into lower-insolation higher, cooler latitudes, allowing us to test these factors by comparing insect species diversity in (1) modern, temperate, low-insolation, highly seasonal Harvard Forest, Massachusetts, U.S.A., 42°29'N; (2) modern, tropical, high-insolation, low-seasonality La Selva, Costa Rica, 10°26'N, and; (3) Eocene, temperate, low-insolation, yet low-seasonality McAbee, British Columbia, Canada, above 50°N paleolatitude. We found insect diversity at McAbee to be more similar to La Selva than to Harvard Forest, with high species richness of most groups and decreased diversity of ichneumon wasps, indicating that seasonality is key to the latitudinal diversity gradient. Further, midlatitude Eocene woody dicot diversities at McAbee, Republic (Washington, U.S.A.), and Laguna del Hunco (Argentina) are also high, similar to modern tropical samples, higher than at the modern midlatitude Harvard Forest. Modern correlations between latitude, species diversity, and seasonal climates were established some time after the Eocene.
Field Study of Ricinus Viking Formation
Authors: Bu F. , Stemler P. , Cheng A.
Published: July 2010

This field study was based on 50 fracturing jobs at 42 wells that Halliburton pumped from 1977 to 2006 for Petro-Canada Oil and Gas Ltd., producing from the Viking formation in the Ricinus area. Four different fluid systems (Guar-borate, CO2, gelled oil and gelled CO2/oil) were investigated to compare their effects on the skin factor, effective fracture half-length, percentage of screenout jobs and production rate. All available fracturing and buildup data were collected and analyzed. Gelled CO2/oil fracture treatment showed the best results on the effective fracture half-length and production rate, and proved to be the best option among these four systems.

This study was also focused on investigating the reasons for a high percentage of fracture jobs being screened out; 85% of the fractures investigated exhibited pressure-dependent leakoff (PDL) behaviour believed to be the primary characteristic of the unsuccessful jobs. Treating the formation at a pressure lower than the fissure opening pressure was considered to be a possible way to avoid screening out. A field case was used to investigate this possibility with the application of a fracture-simulation model, but it was not possible to pump at a rate low enough to prevent opening the natural fractures. Since July 17, 2002, the service company fractured all wells with gelled CO2/oil at high pumping rates and achieved a 100% success rate. This proved that pumping at a high rate is the only option so far to combat PDL and place the proppant successfully. Economic value to the customer (EVC) analysis showed $460,000 in savings on ten gelled CO2/oil high rate fracture jobs for Petro-Canada Oil and Gas Ltd.

Fluid Systems

Four fluid systems have been used to pump 50 fracture stimulation jobs in 42 Ricinus area wells producing from the Viking Formation. Figure 1 shows the area of these 42 wells. Among these 50 fracturing jobs, six used Guar-borate, 12 used gelled oil, 15 used CO2 and 17 used gelled CO2/oil. These fracture stimulation jobs were pumped since 1977. Figure 2 shows the percentage distribution for the four systems involved in this study.
Phase-Behavior Study of Hydrocarbon/Water/Methanol Mixtures at Reservoir Conditions
Authors: Bang Vishal , Pope Gary A. , Sharma Mukul M.
Published: July 2010

This paper presents a study of gas/condensate hydrocarbon mixtures and the effect of water, methanol, and isopropanol on their phase behavior. Only sparse data are available on the phase behavior of hydrocarbon/water/methanol mixtures at the high temperatures typical of these reservoirs. Such data are needed for compositional reservoir simulations of well treatments to optimize the performance of solvent treatments of blocked wells. Constant-composition expansion (CCE) experiments were performed to measure the phase behavior of hydrocarbon/water/methanol mixtures up to 300°F. The effects of temperature, pressure, and water and methanol concentration on the phase behavior were measured. The Peng-Robinson equation of state (EOS) was used to model hydrocarbon/water/methanol mixtures. The binary interaction parameters were tuned to fit the data and were found to show a linear variation with temperature. The binary interaction parameters and temperature-dependent volume-shift parameters are the key parameters to model these complex polar mixtures. Both the classical van der Waals and the Huron-Vidal (Huron and Vidal 1979) mixing rules were used and were found to give good agreement with the data. Phase-behavior experiments performed on hydrocarbon/water/isopropanol mixtures showed that isopropanol decreases the aqueous-phase volume fraction and increases the liquid-hydrocarbon-phase volume fraction compared with the analogous hydrocarbon/water/methanol mixtures. These data are needed to predict the conditions under which methanol/isopropanol treatments can be applied successfully in gas wells to remove water and condensate blockage.
Analysis of Production Data From Hydraulically Fractured Horizontal Wells in Shale Reservoirs
Authors: Medeiros F.. , Kurtoglu B.. , Ozkan E.. , Kazemi H..
Published: July 2010

This paper discusses the analysis of production data from hydraulically fractured horizontal wells in shale reservoirs. The stimulated volume around the well is simulated by a naturally fractured region. A semianalytical model incorporating the key features of reservoir heterogeneity and the details of hydraulic fracture and wellbore flow is used to present production-decline characteristics in terms of transient-productivity index. Production-decline analysis of fractured horizontal wells in shale-oil and shale-gas formations by transient-productivity index is explained and demonstrated by field applications.
Validation of Blowout-Rate Calculations for Subsea Wells
Authors: Oudeman P..
Published: July 2010

Calculating the blowout rate of oil and gas wells is commonly one of the first steps in environmental-impact assessment, contingency planning, and emergency response. The blowout rate is a direct measure for the economic and environmental damage caused by a blowout and an indicator for the effort required to regain control over the well. Hence, a simulator was developed to estimate blowout rates.

This simulator was validated for field cases by comparing calculated blowout rates with estimates based on observable phenomena such as flame length and heat release rates. This limited validation to onshore- and platform-well blowouts, which are usually governed by critical outflow conditions at surface, because ambient pressure is usually considerably less than the wellbore pressure just upstream of the outflow. For subsea wells, blowing out against the substantially higher pressures at seabed, this does not apply. The blowout rate is determined by the total system performance from inflow at sandface to outflow at seabed.

To validate the blowout-rate calculations under these conditions, data were collected on high-rate well flow through an annulus against elevated surface pressures, resembling subsea blowout conditions. A comparison of the measured rates with the calculated rates demonstrated that the rates could be predicted with a high accuracy, provided that the mechanical condition of the tubulars is taken into account properly. Default assumptions for the hydraulic roughness of the tubulars lead to overestimates of the blowout rates and consequently to worst-case estimates for the environmental and economic damage caused by a blowout.
Why We Don't Learn What We Should From HAZOPs
Authors: Duhon Howard J , Sutton Ian
Published: July 2010

During the last 15 years, the process industries have made dramatic improvements in occupational safety. Recordable injury rates have dropped by close to an order of magnitude (Pitlblado 2008). Accurate information pertaining to progress in process safety in the same time period is not available. However, it is likely that improvements in process safety are not nearly so great (Sutton 2009).

From its beginnings in the late 1980s and early 1990s, hazards analysis has been a key item in all process safety programs. After all, if hazards are not identified, they cannot be remediated. Of the various hazards-analysis techniques, the Hazard and Operability Method (HAZOP) has probably gained the greatest acceptance. Therefore, if the process industries are to achieve the same levels of success in process safety as they have in occupational-safety improvements, the effective use of HAZOPs is probably going to be of central importance.

This paper discusses some of the cognitive, social, organizational, and procedural factors that limit the effectiveness of projects in general and of HAZOPs in particular. From this discussion, insights can be developed that can provide ideas for improving the HAZOP process and process-safety-management systems in general.
Faster Convergence in Seismic History Matching by Dividing and Conquering the Unknowns
Authors: Sedighi F.. , Stephen K.D.. D.
Published: July 2010

Seismic history matching is the process of modifying a reservoir simulation model to reproduce the observed production data in addition to information gained through time-lapse (4D) seismic data. The search for good predictions requires that many models be generated, particularly if there is an interaction between the properties that we change and their effect on the misfit to observed data. In this paper, we introduce a method of improving search efficiency by estimating such interactions and partitioning the set of unknowns into noninteracting subspaces. We use regression analysis to identify the subspaces, which are then searched separately but simultaneously with an adapted version of the quasiglobal stochastic neighborhood algorithm. We have applied this approach to the Schiehallion field, located on the UK continental shelf. The field model, supplied by the operator, contains a large number of barriers that affect flow at different times during production, and their transmissibilities are highly uncertain. We find that we can successfully represent the misfit function as a second-order polynomial dependent on changes in barrier transmissibility. First, this enables us to identify the most important barriers, and, second, we can modify their transmissibilities efficiently by searching subgroups of the parameter space. Once the regression analysis has been performed, we reduce the number of models required to find a good match by an order of magnitude. By using 4D seismic data to condition saturation and pressure changes in history matching effectively, we have gained a greater insight into reservoir behavior and have been able to predict flow more accurately with an efficient inversion tool. We can now determine unswept areas and make better business decisions.
An Alternative Method of Dealing With Pressure: Friction Reducer for Water Packing of Long Horizontal Open Holes in Low-Fracturing-Gradient Environments
Authors: Baser B.. , Shenoy S.. , Gadiyar B.. , Jain S.. , Parlar M..
Published: July 2010

Water packing is the most commonly used gravel-packing technique for openhole horizontal completions. With this technique, the packing of a horizontal well occurs through two sequential events, called the α wave and the β wave. Because the carrier fluid is diverted into and must travel through the narrow annulus between the screen base pipe and the wash pipe all the way to the toe, pressure builds up steadily during the β wave as the packing proceeds from toe to heel because of high friction pressures in that annulus. This rise in pressure may result in exceeding the fracturing pressure of the reservoir, which in turn causes a premature screenout and an incomplete gravel pack.

This is a well-known problem, which in the past, often limited the horizontal well length that can be gravel packed in many deep-water developments because of a narrow operating window. Today, various methods are available to solve this problem, including mechanical solutions that create a short cut for fluid returns and the use of lightweight gravel that allows pumping at lower rates without having to worry about gravel settling in the work string but still having an α-wave height that will cover the screens.

In this paper, we present an alternative method of dealing with the pressure rise during the β wave, reducing the friction pressures through addition of a friction reducer to brine carrier fluid. We first detail the laboratory-scale experiments used for screening of many additives considered, including laboratory-scale friction pressure measurements, compatibility with high-density brines, gravel settling, formation, and gravel-pack damage. We then discuss the results from full-scale friction tests conducted in pipe and annular geometries, using the best-candidate friction reducer selected on the basis of laboratory tests. The results indicate that a drag reduction of 20 to 70% is attained with an environmentally friendly friction reducer, with gravel-pack retained permeability in the range of 75 to 90%, depending on test conditions, and with minimal to no impact on gravel settling and, thus, on α-wave height.
Simulation of Two-Phase Flow in Reservoir Rocks Using a Lattice Boltzmann Method
Authors: Ramstad Thomas , Øren Pål-Eric , Bakke Stig
Published: July 2010

We present results from simulations of two-phase flow directly on digitized rock-microstructure images of porous media using a lattice Boltzmann (LB) method. The implemented method is performed on a D3Q19 lattice with fluid/fluid and fluid/solid interaction rules to handle interfacial tension and wetting properties. We demonstrate that the model accurately reproduces capillary and wetting effects in pores with a noncircular shape. The model is applied to study viscous coupling effects for two-phase concurrent annular flow in circular tubes. Simulated relative permeabilities for this case agree with analytical predictions and show that the nonwetting-phase relative permeability might greatly exceed unity when the wetting phase is less viscous than the nonwetting phase.

Two-phase LB simulations are performed on microstructure images derived from X-ray microtomography and process-based reconstructions of Bentheimer sandstone. By imposing a flow regulator to control the capillary number of the flow, the LB model can closely mimic typical experimental setups, such as centrifuge capillary pressure and unsteady- and steady-state relative permeability measurements. Computed drainage capillary pressure curves are found to be in excellent agreement with experimental data. Simulated steady-state relative permeabilities at typical capillary numbers in the vicinity of 10−5 are in fair agreement with measured data. The simulations accurately reproduce the wetting-phase relative permeability but tend to underpredict the nonwetting-phase relative permeability at high wetting-phase saturations. We explain this by pointing to percolation threshold effects of the samples. For higher capillary numbers, we correctly observe increased relative permeability for the nonwetting phase caused by mobilization and flow of trapped fluid. It is concluded that the LB model is a powerful and promising tool for deriving physically meaningful constitutive relations directly from rock-microstructure images.
Support-Vector Regression for Permeability Prediction in a Heterogeneous Reservoir: A Comparative Study
Authors: Al-Anazi A.. , Gates I.D.. D.
Published: July 2010

Permeability is a key parameter in reservoir-engineering computation, and the relationship between rock petrophysical properties and permeability is often complex and difficult to understand by using conventional statistical methods. Neural-network-based methods can be employed to develop more-accurate permeability correlations, but the correlations from these methods have limited generalizability and the global correlations are usually less accurate compared to local correlations. In this research, the objective is to build a permeability model with promising generalization performance. Recently, support-vector machines (SVMs) based on statistical-learning theory have been proposed as a new intelligence technique for both prediction and classification tasks. The formulation of SVMs embodies the structural-risk-minimization (SRM) principle, which has been shown to be superior to the traditional empirical-risk-minimization (ERM) principle employed by conventional neural networks. This new formulation deals with kernel functions, allows projection to higher planes, and solves more-complex nonlinear problems. SRM minimizes an upper bound on the expected risk, as opposed to ERM, which minimizes the error on the training data. It is this difference that equips SVMs with a greater ability to generalize, which is the goal in reservoir-characterization statistical learning. This novel support-vector-regression (SVR) algorithm was first introduced in well-logs intelligent analysis. Here, a permeability-prediction model using SVR from well logs in a heterogeneous sandstone reservoir is developed. Also, an attempt has been made to review the basic ideas underlying support-vector machines for function estimation. To demonstrate the potential of the proposed SVM's regression technique in prediction permeability, a study was performed to compare its performance with multilayer perceptron neural network, generalized neural network, and radial-basis-function neural networks. Accuracy and robustness were investigated, and statistical-error analysis reveals that the SVM approach is superior to the other methods for generalizing previously unseen permeability data.
A Wet Cold-Flow Technology for Tackling Offshore Flow-Assurance Problems
Authors: Azarinezhad R.. , Chapoy A.. , Anderson R.. , Tohidi B..
Published: July 2010

Flow assurance is a major challenge in offshore and deepwater operations. Conventional approaches for preventing gas-hydrate formation involve using thermodynamic inhibitors (e.g., methanol, glycol) or kinetic hydrate inhibitors or operating outside the hydrate- stability zone by insulating the pipeline and/or active heating.

These techniques are not always economical and in some cases are not practical for deepwater operations, long tiebacks, or aging reservoirs with high water cuts. The industry needs new and novel flow-assurance techniques to address these challenging conditions. The approach presented in this paper is a wet cold-flow-based method in which gas-hydrate management rather than prevention is the goal.

The HYDRAFLOW concept is to allow/encourage gas-hydrate formation, but prevent agglomeration in the pipeline and thus avoid blockage. The idea is to convert most of the gas phase into hydrates and transfer it in the form of hydrate-slurry in the pipeline. Where produced water is insufficient for maximum hydrate formation, excess water can be added from other sources such as seawater (hence wet cold flow, because the presence of a free aqueous phase is desired). It is also possible to adjust the hydrate-slurry viscosity by adjusting the amount of water. Antiagglomerants (AAs) and other additives may be necessary to control the hydrate-crystal size and prevent solid blockage in these systems.

Where possible, it is proposed to use a closed-loop concept that allows partial recirculation of the liquid phase and its associated additives. The recycled fluid acts as carrier fluid, transferring produced hydrocarbons to their destination (e.g., platform). In this case, part of the additives, including AAs, can be recycled, reducing the operational costs and potential environmental impact.

This paper presents the latest developments of the HYDRA- FLOW technology, including studies on hydrate-growth rates, viscosity/transportability of slurries for different low- and high- gas/oil-ratio (GOR) systems, and the effect of salts from reservoir brines and/or seawater.
High-Integrity Wellbore Surveying
Authors: Ekseth Roger , Torkildsen Torgeir , Brooks Andrew , Weston John , Nyrnes Erik , Wilson Harry , Kovalenko Kazimir
Published: July 2010

Position-uncertainty estimates are used to determine if there is adequate probability of hitting a geological target, of avoiding collision with offset wells, and of drilling a successful relief well in the event of a blowout. These high-value decisions are based on tool-error-model predictions, the validity of which is highly dependent on the application of rigorous quality-control (QC) procedures to the survey data. Directional surveys that do not conform to their model's error predictions represent a risk in terms of lost production, damage to infrastructure, and loss of life.

This paper documents weaknesses in conventional directional-survey QC procedures. Theoretical considerations, statistical analyses of real survey data, and real examples of failed surveys that have made it through conventional QC procedures without detection are presented. The paper defines principles for survey-program design and implementation to eliminate these weaknesses. It proposes a new set of minimum requirements for survey validation.

Where the cumulative QC data do not support the model, it is necessary to adjust the model to fit the data. In the longer term, it might be possible to rework the tools and procedures in the hope of meeting the original model's specification, but the uncertainty estimate assigned to a survey must be valid at all times.

The methods described in this paper are capable of ensuring valid positional data and should be incorporated into standard practice. However, to implement these techniques correctly and consistently, it is probably necessary to establish a specialized supervisory function, responsible for the integrity of wellbore positioning across a company's entire operation.

This paper is the product of a collaborative work within the SPE Wellbore Positioning Technical Section (SPE-WPTS), and combines two previous papers on the subject by Ekseth et al. (2006, 2007).
Simulation Analysis of the Effects of Fractures? Geometrical Properties on the Performance of Vapour Extraction Process
Authors: Fatemi Seyyed M. , Bahonar Mehdi
Published: July 2010

Vapour extraction (VAPEX), a newly developed heavy oil recovery (HOR) method, has been extensively studied, both theoretically and experimentally, in conventional sandstone models. However, the applicability of this process to naturally fractured reservoirs has not yet been addressed. The objective of this work is to evaluate the effects of fractures' geometrical properties, such as orientation, length of extension, discontinuity in both the upper well region (UWR) and the far well region (FWR) and vertical fracture location on VAPEX performance. Additionally, the effects of horizontal and vertical fracture dispersion in various density, dispersion scheme and networking on the performance of the VAPEX process are assessed. A fracture's discontinuity effect has also been scrutinized in the presence of parallel-piped networked fractures, which confirmed the results in the case of either horizontal or vertical fracture systems. It was found that the VAPEX process enhances performance in the case of longer vertical fractures, lower horizontal fracture dispersion, shorter horizontal fracture extension and lower vertical fracture discontinuity. Vertical fracture dispersion scheme also affects performance. The ultimate oil recovery, in the case of networked fractures, will be higher than the conventional model if the horizontal fractures have poor connectivity to each other.
Numerical Simulation and Economic Evaluation of Hybrid Solvent Processes
Authors: Frauenfeld Ted W.J. , Jossy Chris , Ivory John
Published: July 2010

Solvent-based processes for recovery of heavy oil and bitumen have potential application to a variety of reservoir situations. Potential processes range from steam assisted gravity drainage (SAGD) to VAPEX, with a range of hybrid processes in between. Over 50 laboratory-scale and 80 field-scale simulations were run to determine optimum operating points for various hybrid processes. The results showed that steam-butane simulations yielded two "sweet spots" where the cost objective function was lower than that for SAGD. Economic analysis was done based on a set of field-scale simulations. This analysis showed that a hybrid solvent process for an Athabasca reservoir was an alternative to SAGD. The analysis may be extended to other reservoir types as needed.
Environmental Considerations in Waste Disposal from Drilling In the Shallow Beaufort Sea
Authors: Swanston H.W. , Heffler H.R.
Published: July 2010

Imperial Oil Limited's exploration program in the Canadian Arctic hasreceived close examination of the environmental consequences of marine disposalof drilling wastes. An extensive literature search provided data to assess theaquatic ecology and to identify potentially deleterious effects on theenvironment. Beak Consultants' laboratories analyzed samples of drilling wastefor a broad spectrum of physical and chemical characteristics. They alsoevaluated acute toxicity, using standard laboratory bioassay methods. Study ofseveral alternative methods of waste disposal identified two methods ofpretreatment which merited on-site testing. Both aeration, to reduce oxygendemand and acute toxicity, and filtration to reduce the volume of dischargedsolids were evaluated.

To date, drilling wastes have been discharged to both the open andice-covered waters of the Beaufort Sea. A local blanketing effect and a changein the pH in the immediate vicinity of the discharge point were the onlyenvironmental concerns expressed. This study concluded that, except for pHadjustment and removal of extraneous contaminants, no other treatment isrequired for the systems examined. Monitoring is continuing in order to assessthe long-term environmental impact at these Arctic drilling sites.

Introduction

The work reported here covers two studies done by Imperial Oil Limited and Beak Consultants Limited. The objective of the first project was to examine theinfluence of the disposal of drilling wastes from off-shore exploration wellsin the Mackenzie Delta on the immediate marine environment. In the secondproject, two methods of treatment of drilling wastes were evaluated by fieldtesting. This work also included monitoring of the discharged volume andsampling for chemical and bioassay analyses.
Lake Erie - offshore natural gas exploration and development opportunities in Ontario
Authors: Fox John N. , Rybansky Rudy M. , Trevail Robert A.
Published: July 2010

Lake Erie is the fourth largest of the Great Lakes covering an area of 25665 km2. The international boundary runs through the lake and 12 768km2 of the lake are under the control of the province of Ontario.The oil and natural gas rights under Lake Erie are owned by the province of Ontario. This paper describes the province's Lake Erie land tenure system ofexploratory licences and production leases. The paper also presents an overviewof offshore drilling, completion and production operations in Lake Erieincluding typical costs associated with such operations. When examining anyexploration and development opportunities it is essential that consideration begiven to the various factors that influence the attractiveness of suchopportunities. To this end, this paper presents a brief description of thegeology and reservoir characteristics of producing horizons underlying thelake, a summary of the lake's remaining proven and potential natural gasreserves and the advantages enjoyed by Ontario natural gas producers withrespect to gas pricing and marketing.

Introduction

The mineral rights under the waters of Lake Erie (Fig. 1) are held by the Crown in the right of Ontario. The lands are disposed of by the Ontario Ministry of Natural Resources in accordance with regulations under the Mining Act. The regulations provide for the granting of exploratory licences ofoccupation and production leases. The objectives of the Lake Erie land tenuresystem are to ensure the orderly and efficient development, in the publicinterest, of the natural gas resources of the province while providing anattractive investment climate for the oil and gas industry.