bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanical properties and microstructural analysis of a diamond-like carbon coating on an alumina/glass composite
Authors: Christiansen S. , Albrecht M. , Strunk H. P. , Hornberger H. , Marquis P.M. , Franks J.
Published: March 2008

We investigate the mechanical and microstructural properties of a diamond-like carbon coating (DLC) which is deposited by plasma enhanced chemical vapor deposition (PECVD) onto an alumina/aluminosilicate glass composite used for biomedical applications. Ball-on-ring tests yield a fracture strength that is essentially influenced by the surface topology/roughness. The surface topology of the coating is investigated by atomic force microscopy (AFM). Tribology tests and nanoindentation represent the wear resistance and hardness; these are properties that are mainly influenced by the microstructural properties of the DLC coating. This microstructure is investigated by transmission electron microscopy (TEM) and analyzed by parallel electron energy loss spectroscopy (PEELS). For the general applicability of the coated composite, the interfacial adhesion of the DLC coating on the comparably rough substrate (roughness amplitudes and wavelengths are in the micrometer range) is important. Therefore, we focus on TEM investigations that show the interface to be free of gaps and pores that we, together with a characteristic microstructure adjacent to the interface, relate to the excellent adhesion. The interlayer consists of a high density of SiC grains, part of them directly bound to the substrate, and part of them bound to other SiC grains. This interlayer is followed by an essentially different region of the coating as concerns the microstructure; this region consists of nanocrystalline diamond particles embedded in an amorphous carbon matrix. It is this heterogeneous microstructure to which we attribute (i) the good adhesion based upon the interface stabilizing SiC grains, and (ii) the high hardness and wear resistance based upon the diamond nanocrystals in the coating.
The effect of nitrogen on pulsed laser deposition of amorphous silicon carbide films: Properties and structure
Authors: Yee Andrew L. , Ong H. C. , Xiong Fulin , Chang R. P. H.
Published: March 2008

The influence of nitrogen on amorphous silicon carbide films deposited at room temperature using pulsed laser ablation has been investigated. Depositions were carried out either in ultrahigh vacuum or in a nitrogen ambient ranging from 10 to 100 mT. The mechanical and optical properties, as well as composition and structure of the resulting films, were evaluated using a variety of analytical techniques. Vacuum-deposited films exhibited high hardness but suffered from high compressive stresses (>1 GPa). At low nitrogen background pressures (<30 mT), films with an optimum balance among hardness (∼16 GPa), adhesion, and intrinsic stress (<220 MPa) were found, making them ideal candidates for protective coating applications. As nitrogen pressure was increased, mechanical performance degraded due to the increasing amount of SiO2 found in the films as evidenced by spectroscopic ellipsometry, infrared spectroscopy, and Auger electron spectroscopy measurements. The source of oxygen is attributed to residual water vapor present in our vacuum system. Optical emission spectroscopy was used to confirm the presence of Si–O species in the laser-induced plasma plume.
Composition dependence of morphology, structure, and thermoelectric properties of FeSi2 films prepared by sputtering deposition
Authors: Tsunoda Tatsuo , Mukaida Masakazu , Watanabe Akio , Imai Yoji
Published: March 2008

Direct β–FeSi2 film preparation from gaseous phase was examined using a radio-frequency (rf) sputtering deposition apparatus equipped with a composite target of iron and silicon. Films composed of only β–FeSi2 phase were formed at substrate temperatures above 573 K when the chemical composition of the film was very close to stoichiometric FeSi2. The β–FeSi2 films thus formed showed rather large positive Seebeck coefficient. When the chemical composition of the films were deviated to the Fe-rich side, ∈–FeSi phase was formed along with β–FeSi2. On the other hand, α–FeSi2 phase, which is stable above 1210 K in the equilibrium phase diagram, was formed at the substrate temperature as low as 723 K when the chemical composition was deviated to the Si-rich side. The formation of α–FeSi2 phase induced drastic changes in the morphology and thermoelectric properties of the films. The α–FeSi2 phase formed in the films was easily transformed to β–FeSi2 phase by a thermal treatment.
Structural transitions and electrical conductivity of C60 films at high temperature
Authors: Gong Jinlong , Ma Guobin , Chen Guanghua
Published: March 2008

X-ray diffraction analysis on C60 films shows that besides fcc phase, there also exists hcp phase, as well as a new crystalline phase with interplanar spacing (d-spacing) of planes parallel to the substrate 0.95 nm. The new phase may relate to the intercrystalline packed C60 molecules between fcc crystallites. The room temperature electrical conductivity of C60 films is found to be in the range of 10−5–10−8 (Ω · cm)−1. The room temperature conductivities of C60 films annealed at temperatures above 473 K are lower by one order of magnitude than those at temperatures below 463 K. This is because the interconnection between the fcc crystallites is weakened due to the disappearance of the new intercrystalline phase and the subsequent heightening of the intercrystalline potential barrier. From the measurement on the conductivity versus time when the film is maintained at a constant temperature, we identified the increase of conductivity is the result of the decrease of hcp phase, while the decrease of conductivity is due to the decrease of the new intercrystalline phase. Because the structures of the films become highly ordered, and defect states in the energy band gap decrease on annealing at high temperature, the conductivity activation energy increases.
Triagem familiar para o gene HBB*S e detecção de novos casos de traço falciforme em Pernambuco
Authors: Bandeira Flavia Miranda Gomes C , Santos Magnun Nueldo Nunes , Bezerra Marcos André M , Gomes Yara M , Araujo Aderson Silva , Braga Maria Cynthia , Souza Wayner Vieira , Abath Frederico G C
Published: March 2008

OBJETIVO: Estimar o incremento no número adicional de afetados com base na prevalência de síndromes falciformes em familiares de casos-índice. MÉTODOS: Estudo transversal em familiares de amostra aleatória dos casos-índice identificados por programa de triagem neonatal em Pernambuco, no período de 2001 a 2005. O modelo de triagem familiar ampliado incluiu 463 membros familiares de 21 casos-índice. Os familiares foram categorizados como: núcleo reduzido (NR -pai, mãe e irmãos); de primeiro grau (N1 - avós, tios e primos de primeiro grau); de segundo grau (N2 - filhos dos primos de primeiro grau); ampliado (NA - NR+N1+N2) e ampliado de primeiro grau (NA1 -NR+N1). A confirmação da presença de HBB*S e detecção de hemoglobinas anormais foram realizadas por meio da High Performance Liquid Chromathgraphy. A associação entre a presença de HBB*S e variáveis foi testada pelo cálculo da razão de prevalência e respectivos IC 95% e a diferença entre médias verificadas pelo teste t de Student, ao nível de significância de 5%. RESULTADOS: A anemia falciforme era desconhecida por 81% dos familiares; o gene HBB*S esteve presente em 114 familiares. Observou-se que 53,3% da população estudada estava na faixa considerada reprodutiva e 80% das pessoas portadoras do gene HBB*S já tinham gerado filhos. A freqüência foi maior no núcleo NR (69%), mas também elevada no N1 (22,8%). O NA1 resultou na detecção de 69 portadores adicionais (aumento de 172%). CONCLUSÕES: Os resultados indicam que a triagem familiar para identificação de portadores de síndrome falciforme deve ser estendida para os familiares até o primeiro grau.
Knowledge, attitude and practice of mammography among women users of public health services
Authors: Marinho Luiz Alberto Barcelos , Cecatti José Guilherme , Osis Maria José Duarte , Gurgel Maria Salete Costa
Published: March 2008

OBJECTIVE: To evaluate knowledge, attitude and practice related to mammography among women users of local health services, identifying barriers to its performance. METHODS: A total of 663 women were interviewed at 13 local health centers in a city of Southeastern Brazil, in 2001. Interviewees were randomly selected at each center and they were representative from different socioeconomic conditions. The number of interviewees at each center was proportional to monthly mean appointments. For data analysis, answers were described as knowledge, attitude, practice and their respective adequacies and then they were correlated with control variables through the chi-square test. RESULTS: Only 7.4% of the interviewees had adequate knowledge on mammography, while 97.1% of women had an adequate attitude. The same was seen for the practice of mammography that was adequate in 35.7% of the cases. The main barrier to mammography was lack of referral by physicians working at the health center (81.8%). There was an association between adequacy of attitude and five years or more of education and being married. There was also an association between adequacy of mammography practice and being employed and family income up to four minimum wages. CONCLUSIONS: Women users of local health services had no adequate knowledge and practice related to mammography despite having an adequate attitude about this exam.
Alcoolemia em vítimas fatais de acidentes de trânsito no Distrito Federal, Brasil
Authors: Modelli Manoel Eugenio dos Santos , Pratesi Riccardo , Tauil Pedro Luiz
Published: March 2008

O objetivo do estudo foi analisar a presença de alcoolemia em vítimas fatais de acidentes de trânsito, no Distrito Federal, em 2005. De 442 óbitos, 163 foram resultantes de atropelamentos, 84 de capotagem e 195 de colisão. A alcoolemia foi dosada em 238 casos (53,7%). A maioria das vítimas era jovem, entre 18 e 35 anos e do sexo masculino. Entre as vítimas de colisão, 44,2% tinham níveis de alcoolemia acima de 0,6 g/l; nas vítimas de capotagens, esse percentual foi de 57,7% e, entre os pedestres, 32,5%. A diferença entre as proporções de vítimas com alcoolemia positiva foi estatisticamente significativa para os que sofreram acidentes de capotagem em relação aos demais.
Perfis de saúde dos idosos no Brasil: análise da Pesquisa Nacional por Amostra de Domicílios de 2003 utilizando o método grade of membership
Authors: Alves Luciana Correia , Leite Iúri da Costa , Machado Carla Jorge
Published: March 2008

O objetivo deste estudo foi identificar os perfis de capacidade funcional e saúde dos idosos no Brasil, bem como a prevalência destes perfis, no ano de 2003. Os dados foram obtidos da Pesquisa Nacional por Amostra de Domicílios de 2003 (PNAD 2003). A amostra foi constituída de 33.786 idosos. O Grade of Membership foi utilizado na definição dos perfis. Três perfis foram gerados. Os idosos com total pertinência ao Perfil 1 ("idosos saudáveis") foram caracterizados por possuírem menor probabilidade de ocorrência de qualquer tipo de incapacidade funcional e doenças crônicas em relação à população total. Os idosos com pertinência total ao Perfil 2 ("idosos com incapacidade funcional leve") apresentaram principalmente hipertensão e problemas na coluna. Quanto à capacidade funcional, os idosos foram independentes nas atividades de vida diária e apresentaram grande dificuldade na mobilidade. Os idosos tipos puros do Perfil 3 ("idosos com incapacidade funcional grave") tiveram maior probabilidade de ocorrência de todas as doenças crônicas, grande dificuldade com as atividades de vida diária e dependência na mobilidade. Os perfis observados apontam que a abordagem da capacidade funcional se torna essencial para a promoção da saúde dos idosos.
Overcoming health inequity: potential benefits of a patient-centered open-source public health infostructure
Authors: Marques Jr. Ernesto T. A. , Maciel Filho Romulo , August Paul Nordstrom
Published: March 2008

The past 20 years have witnessed an astonishing increase in computational power and an incredible reduction in the cost of contemporary computer systems, but the public health infostructure in most countries has not changed significantly. This article discusses the potential benefits of applying patient-centered infostructure at the primary medical "points-of-care" services, based on networked integrated open-source technology and programming standards to develop tools to detect and reduce health inequalities. Such systems, which could be implemented from the local to the national level, would enable the expansion of evidence-based medicine, clearer identification of health inequalities, and more accurate cost-benefit analyses. In addition, the public health sector could link such databases to traditional Electronic Patient Record (EPR) systems at a greatly reduced cost by promoting the use of standards-based formats for data transfer and storage. Ultimately, the new health infostructure would help decrease health inequity. In fact, developing countries like Brazil, India, and South Africa are well-positioned to take advantage of the open-source movement and "leapfrog" countries burdened by legacy systems.
Corrimento vaginal referido entre gestantes em localidade urbana no Sul do Brasil: prevalência e fatores associados
Authors: Fonseca Tânia M. V. da , Cesar Juraci A. , Hackenhaar Arnildo A. , Ulmi Eduardo F. , Neumann Nelson A.
Published: March 2008

Por intermédio de delineamento transversal, buscou-se determinar a prevalência e identificar fatores associados à ocorrência de corrimento vaginal referido entre gestantes da cidade de Rio Grande, Rio Grande do Sul, Brasil. Utilizando-se de questionário padrão, foram investigadas características sócio-econômicas, demográficas, reprodutivas, condições de moradia, assistência recebida e ocorrência de corrimento vaginal referido entre estas gestantes. Para as comparações entre proporções utilizou-se teste do qui-quadrado e para análise multivariada regressão de Poisson. Dentre as 339 gestantes estudadas, 51,6% referiram corrimento vaginal na gestação. As seguintes variáveis mostraram-se significativamente associadas à ocorrência de corrimento vaginal referido: idade (razão de prevalências: RP= 1,49), estado civil (RP = 1,31), ocorrência de infecção urinária (RP = 1,56), hiperglicemia na gestação atual (RP = 1,48), uso de dispositivo intra-uterino (RP = 2,35), ocorrência prévia de parto prematuro (RP = 1,37) e utilização de anticoncepcional oral como fator de proteção (RP = 0,79). Este estudo mostrou prevalência elevada de corrimento vaginal referido entre as gestantes estudadas e permitiu identificar aquelas com maior risco de adoecer por esta causa, o que pode contribuir para a adoção de medidas preventivas.
Sistema de informações hospitalares do sistema único de saúde (SIH-SUS): uma avaliação preliminar do seu desempenho no monitoramento da doença hemolítica perinatal Rh(D)
Authors: Lobato Gustavo , Reichenheim Michael Eduardo , Coeli Claudia Medina
Published: March 2008

Considerando a utilização de bases administrativas na vigilância epidemiológica, propõe-se aqui avaliar a adequação do Sistema de Informações Hospitalares do Sistema Único de Saúde (SIH-SUS) na identificação dos casos de doença hemolítica perinatal ocorridos no Instituto Fernandes Figueira, Fundação Oswaldo Cruz (IFF/FIOCRUZ), entre 1998 e 2003. Foram analisadas informações disponibilizadas pelo Serviço Neonatal, pelo Arquivo Médico e os dados da Autorização de Internação Hospitalar (AIH) consolidados no SIH-SUS. A identificação dos casos de doença hemolítica perinatal se deu através dos campos Diagnóstico Primário, Diagnóstico Secundário e Procedimento Realizado. Nesse período, 194 neonatos foram diagnosticados com doença hemolítica perinatal. No Arquivo Médico, 148 casos foram registrados, porém apenas 147 AIHs foram emitidas e 145 consolidadas no SIH-SUS. Entre essas, 84 AIHs arrolavam a doença hemolítica perinatal como Diagnóstico Primário; considerando também o Diagnóstico Secundário, mais 38 casos foram identificados; e nenhum caso adicional foi recuperado pelo Procedimento Realizado. Assim, o SIH-SUS identificou apenas 122 (62,9%) dos 194 neonatos com doença hemolítica perinatal assistidos no IFF/FIOCRUZ. Mesmo que ainda requerendo uma reavaliação em outros hospitais, a utilização do SIH-SUS no monitoramento da doença hemolítica perinatal não parece recomendável. Estudos ancilares são necessários quando do emprego de dados secundários nesse contexto.
O trabalho em saúde mental: um estudo de satisfação e impacto
Authors: Rebouças Denise , Abelha Lúcia , Legay Letícia Fortes , Lovisi Giovanni Marcos
Published: March 2008

Apesar da importância, no planejamento de políticas públicas, do conhecimento da satisfação e do impacto do trabalho nos profissionais de saúde mental, há escassez de estudos sobre o assunto no Brasil. Este estudo investigou a satisfação e o impacto do trabalho em 133 profissionais de quatro serviços de saúde mental do Rio de Janeiro, com as escalas SATIS-BR, IMPACTO-BR e um questionário sobre características sócio-demográficas e do trabalho. Para a análise das associações entre variáveis foram empregados os testes Kruskal-Wallis, Mann-Whitney, qui-quadrado e regressão linear múltipla. O programa SPSS 10.1 foi utilizado nas análises. O escore médio de satisfação foi de 3,30 e o escore médio de impacto foi de 2,08, em escala variando de 1 até 5. Sessenta e dois vírgula quatro por cento dos profissionais apresentaram um nível intermediário de satisfação. Observou-se que quanto maior a escolaridade, menor a satisfação. O impacto do trabalho não está associado com quaisquer das variáveis estudadas. O nível intermediário de satisfação obtido é compatível com os resultados de outros estudos. O impacto do trabalho sobre estes profissionais é reduzido. Diferentemente de outros estudos realizados nos Estados Unidos e Europa, não foram observadas diferenças entre equipes hospitalares e comunitárias.
Relacionamento probabilístico de registros: uma aplicação na área de morbidade materna grave (near miss) e mortalidade materna
Authors: Sousa Maria Helena de , Cecatti José Guilherme , Hardy Ellen , Serruya Suzanne Jacob
Published: March 2008

Apresentar uma experiência de relacionamento do Sistema de Informações Hospitalares (SIH) com o Sistema de Informações sobre Mortalidade (SIM), e do SIH com ele próprio, aplicados na área de morbidade materna grave (near miss) e mortalidade materna. Trata-se de um estudo empírico, utilizando-se dados brasileiros das capitais de estados e do Distrito Federal em 2002. Para os dois relacionamentos, aplicados separadamente em cada uma das capitais, estabeleceu-se estratégia de blocagem em três passos simples, bem como a de múltiplos passos relacionados, e duas de revisão manual. Do total de pares verdadeiros dos dois relacionamentos, menos de 8% não puderam ser localizados pelos passos simples, enquanto que a estratégia de múltiplos passos deixou de localizar apenas 0,7%. Foi possível explorar o assunto de mortalidade e morbidade materna grave nos bancos de dados. O número de pares formados e revisados sob a estratégia de múltiplos passos foi inferior à soma dos pares nos três passos simples e, além disso, menos pares foram perdidos. Porém, para o relacionamento do SIH com ele próprio, sugerem-se as duas estratégias.
Resolutividade dos serviços de saúde por inquérito domiciliar: percepção do usuário
Authors: Turrini Ruth Natalia Teresa , Lebrão Maria Lúcia , Cesar Chester Luiz Galvão
Published: March 2008

Estudo para identificar a capacidade resolutiva dos serviços de saúde utilizados pela população que referiu pelo menos um problema de saúde nos 15 dias anteriores à entrevista, e conhecer sua percepção sobre a resolução deste problema. As informações foram obtidas de inquérito domiciliar realizado com 10.199 entrevistados na região sudoeste da Grande São Paulo, Brasil, entre 1989/1990. Destes, 31,3% referiram algum episódio de doença e 47,7% procuraram ajuda para resolver o problema. O serviço de atenção primária à saúde foi a principal porta de entrada no sistema (35,7%), seguido pelos hospitais (25,4%) e clínicas/ambulatórios (24,3%). A capacidade resolutiva dos serviços para as consultas médicas foi superior a 90%; 44,5% referiram solução do problema de saúde, 35,5% estavam em tratamento e 10,5% não tiveram seu problema resolvido. A maioria dos problemas resolvidos pertencia ao capítulo das doenças dos aparelhos respiratório e digestivo, infecciosas e parasitárias e sinais e sintomas mal definidos. A proporção de indivíduos ainda em tratamento não permitiu concluir que os serviços eram resolutivos à época do inquérito, embora tenham sido capazes de atender à demanda.
Acompanhamento do crescimento em crianças menores de um ano: situação nos serviços de saúde em Pernambuco, Brasil
Authors: Carvalho Michelle Figueiredo , Lira Pedro Israel Cabral de , Romani Sylvia de Azevedo Mello , Santos Iná S. , Veras Ana Amélia Corrêa de Araújo , Batista Filho Malaquias
Published: March 2008

Realizou-se um diagnóstico situacional da ação de acompanhamento do crescimento em menores de 1 ano da Região Metropolitana do Recife e interior do Estado de Pernambuco, Brasil. Foi utilizado o banco de dados da pesquisa Atenção à Saúde Materno-infantil no Estado de Pernambuco, constituído por 816 crianças e 120 unidades de saúde. Para a análise utilizou-se o Epi Info versão 6.04. Na estrutura dos serviços observou-se que 15,8% das unidades de saúde não dispunham de balança pesa-bebê nem de Cartão da Criança; 75,4% não possuíam as normas de acompanhamento do crescimento e desenvolvimento. Dessas variáveis, as duas primeiras revelaram diferença entre as áreas estudadas. Quanto ao processo, 81,2% das mães dispunham do cartão da criança; 53,1% das crianças foram pesadas; e apenas 21% foram medidas em seu comprimento. A orientação dada às mães foi bastante deficitária. Nessas variáveis houve diferença entre as duas áreas. A atenção à criança sob risco nutricional foi pouco considerada nas duas áreas, embora não tenha revelado diferença significante entre interior e região metropolitana. Portanto, a ação de acompanhamento do crescimento não estava efetivamente consolidada no Estado de Pernambuco.
Fórum: racionamento dos cuidados de saúde. Introdução
Authors: Pinho Micaela Moreira
Published: March 2008

O racionamento explícito dos cuidados de saúde é um dos temas mais importantes em discussão nos meios acadêmicos e políticos nos países desenvolvidos e em desenvolvimento. Os artigos apresentados neste Fórum propõem-se a abordar algumas das questões suscitadas por essa problemática. A abordagem é multidisciplinar percorrendo as complexas questões da ética e a contribuição da economia para a reflexão. As análises revelam as especificidades associadas à mudança de uma abordagem implícita de racionar os cuidados de saúde, tradicionalmente dominante nos sistemas de saúde, para um método sistemático e explícito de priorização, em geral, e a potencial incompatibilidade entre os objetivos da eficiência e da eqüidade nas políticas de saúde, em particular. As reflexões do Fórum estão diretamente relacionadas com as correntes discussões em torno das questões "Por que racionar os cuidados de saúde?" e "Como racionar os cuidados médicos?", presentes em todo o mundo.
Racionamento dos cuidados de saúde: problemática inerente
Authors: Pinho Micaela Moreira
Published: March 2008

A escassez de recursos que caracteriza os sistemas de saúde obriga a tomada de decisões de priorização que se traduzem em escolhas entre programas/serviços alternativos e/ou entre pacientes ou grupos de pacientes. Na ausência de mecanismo de preços, o estabelecimento de prioridades consagra uma forma de afetação dos escassos recursos no mercado dos cuidados de saúde, traduzido em racionamento. Tradicionalmente, nos sistemas de saúde públicos as decisões de afetação dos recursos têm sido tomadas de forma discricionária, sobretudo pelos médicos. Contudo, a crescente limitação dos recursos, associada a um aumento das expectativas por parte dos doentes, apela a formas mais explícitas de racionamento legitimadas socialmente. Internacionalmente, o desenvolvimento de processos explícitos de priorização tem-se revelado difícil e controverso.
Racionamiento vía listas de espera: medidas de mejora y posibles implicaciones
Authors: Rodríguez Eva , Álvarez Begoña , Abad Pilar
Published: March 2008

En este trabajo se discuten las principales estrategias que se han planteado en la gestión sanitaria para mejorar la situación de las listas de espera. En primer lugar, se describen aquellas medidas que tratan de mejorar los indicadores tradicionales de las listas de espera (tiempo de espera y tamaño de la lista), distinguiendo entre aquéllas que tratan de incidir en el incremento de la oferta y las que tratan de controlar la demanda. En segundo lugar, se analizan aquellas medidas que no implican necesariamente una mejora en los indicadores tradicionales, pero sí consiguen mejoras significativas en la calidad de la espera. Para cada una de las estrategias se muestran tanto sus efectos esperados como otros efectos colaterales que alertan sobre su eficacia a la hora de mejorar la situación de las listas de espera.
A Case-Based Approach to Understand the Complexity of Causal Connections Related to Well Integrity Problems
Authors: Abdollahi J. , Carlsen I. M. , Randhol P. , Tenold E. , Haga H. B. , Jakobsen T.
Published: March 2008

This paper demonstrates the applicability of a combined Case-Based Reasoning (CBR) and Model-Based Reasoning (MBR) methodology for diagnosis of well integrity problems. Through 18 selected cases, it is shown how previous solved cases and experience can be systemized and used for new and unsolved cases. Researchers at SINTEF Petroleum Research have assisted Norsk Hydro (now StatoilHydro) in their work to understand the causal connections of leaking wells at the Norwegian Continental Shelf. Norsk Hydro's database, including both leaking and non-leaking wells, has formed the basis for this work. A chronological documentation of the well activities, observations, actions and outcomes during the well life-cycle has been studied. The experience from this study shows that implementing and demonstrating this methodology is a time consuming process. This is due to the novelty of this methodology to the petroleum industry and the lack of a defined template. The main challenge for further tool development is related to the encoding for formulating the cases in question.
Capillary-Tube Technology in Downhole Pressure Acquisition and its Application in Campos Basin, Brazil
Authors: Cassarà Pier Giovanni , Almanza Edgar , Burgoa Juan Carlos , Ringgenberg Paul
Published: March 2008

A capillary-tube realtime data acquisition system has been installed in the BG-16 Petrobras Well, located at Bagre Field, Campos Basin, Brazil to acquire downhole pressure data in real time. Petrobras considers cost-effectiveness, safety, and reliability as important requirements for any downhole pressure monitoring system. Therefore, any new technologies that offer the possibility of improving these criteria are considered for trial by Petrobrás.

This paper discusses the results of the first use of the capillary-tubing downhole monitoring system in Brazil to collect reservoir information for pressure transient analysis during flowing and surface shut-in periods. The results are then compared with reservoir information collected by other methods; i.e., downhole pressure gauges and memory gauges, to allow evaluation of the performance of this system against other data-acquisition techniques.

The results attained from use of this system illustrate the benefits of this application for long-term continuous reservoir monitoring. The system not only provided the engineers with the capability to determine the reservoir geometry and to make future field development decisions based in the analysis of the information collected during the reservoir evaluation, but also, it allowed the analysis of two transients at different moments during the production life of the evaluated well to be made.

These enhancements resulted in improved economics, more extensive reservoir knowledge, operational efficiency, and greater safety both for the involved personnel and the environment to be realized.
US Chemical Safety Board: Fatal Oilfield Investigation and Industry Lessons Learned
Authors: Banks Johnnie
Published: March 2008

This Case Study examines an explosion at the Partridge-Raleigh oilfield in Raleigh, Mississippi. The incident occurred at about 8:30 a.m. on June 5, 2006, when Stringer's Oilfield Services contract workers were installing pipe from two production tanks to a third (figure 1). Welding sparks ignited flammable vapor escaping from an open-ended pipe about four feet from the contractors' welding activity on tank 4. The explosion killed three workers who were standing on top of tanks 3 and 4. A fourth worker was seriously injured.

In the weeks preceding the incident, Stringer's workers had relocated tanks 3 and 4 from other oilfield sites on the Partridge-Raleigh property to the #9 well site. On the day of the incident, the four workers were completing the piping connection between the tanks.

To connect the piping from tank 3 to tank 4, the workers had to weld a pipe fitting onto the side of, and a few inches below the top of, tank 4. To prepare for the welding operation, they removed the access hatch at the base of tank 4 and entered the tank to remove the crude oil residue. Then they flushed the tank with fresh water and allowed hydrocarbon vapor to evaporate for several days. They did not clean out or purge tanks 2 and 3.
Deepwater Bitumen Drilling: What Happened Downhole?
Authors: Han Gang , Hunter Keith , Ressler Jamie , Osmond Jerry
Published: March 2008

Bitumen formations have posed significant challenges to deepwater Gulf of Mexico drilling operations. Many operators such as ConocoPhilips (Spa Prospect), Chevron (Big Foot), BP (Mad Dog) have reported bitumen encounters and associated significant costs. The current consensus is to avoid bitumen formations as much as possible. However, fundamental questions still remain unclear and controversial. For example, what bitumen behaves at in-situ conditions (i.e. high stress and high temperature), what shape is bitumen formation, what mechanisms drive bitumen into wellbore.

This paper highlights a part of comprehensive efforts to drill through the bitumen encountered in a deepwater Gulf of Mexico field. A series of lab tests have been done to investigate the effect of temperature, pressure, and drilling fluids on bitumen mechanical behaviors. A material model for in-situ bitumen is therefore derived and applied in detailed 3D numerical analyses. At reservoir scale, the numerical models analyze the stress and deformation inside and around the bitumen formations with different lateral extensions and thickness, and evaluate the stability of various bitumen shapes at in-situ conditions. At wellbore scale, 3D models are used to study the factors of bitumen mobilization, including overburden stress, bitumen stress, and borehole pressure. The relative importance of each factor has been quantified.

One of the key findings is the role of overburden in bitumen mobilization. We find that, for the bitumen encountered adjacent to the salt body, the radial stress gradient (i.e. horizontal if well is vertical) is dominant to flow the bitumen at the beginning after borehole introduction. The overburden effect becomes evident later. Further, both mechanisms result in stress concentrations within short distance around the wellbore. Another finding contradictory to previous publications is the mud pressure required to stop bitumen movement. The simulations indicate for the bitumen studied in this paper as long as the mud pressure at the bitumen formation reaches the level of in-situ minimum horizontal stress (i.e. fracture gradient instead of overburden gradient), the bitumen stops moving. However, even 0.25ppg mud pressure fluctuation may trigger the mobilization again.

These studies improve the understandings of in-situ bitumen and near-wellbore bitumen flow conditions, and may help to develop a successful strategy to drill through.
Complex Extended-Reach Drilling to Exploit Reservoirs in Environmentally Sensitive Area, Offshore California
Authors: Hertfelder Gary P. , Menge Mathias , Patel Max , Ruszka Jon
Published: March 2008

The marine environment offshore California is an environmentally sensitive location. To minimise environmental impact, platforms installed in the 1980's continue to be utilised for field development without the requirement to install additional jackets or disturb the seabed with subsea completions and flow lines. As the field developments continued, extended reach drilling (ERD) techniques were developed and employed to exploit the outer reaches of the fields and develop new satellite deposits. In order to fully utilise the capabilities of the existing platforms and as they became slot constrained, ERD sidetracks from existing ERD wells became necessary. Some of these sidetracks required highly complex three-dimensional profiles to reach the new targets.

This paper discusses some of the challenges drilling offshore California and how the use of extended reach drilling techniques allowed full utilisation of available drilling infrastructure while minimising environmental impact. Also discussed is the specialist drilling technologies employed on these challenging wells together with lessons learned, illustrated with examples from real wells.
A Design Strength Equation for Collapse of Expanded OCTG
Authors: Klever Frans J.
Published: March 2008

Expandable tubulars provide exciting new opportunities for well design and construction. This technology has permitted access to hydrocarbons that could not be reached by conventional drilling techniques. Design tools similar to those available for conventional oil country tubular goods (OCTG) are required to facilitate further dissemination and application of expandable tubulars. In particular, equations for performance properties of expanded pipe are needed.

This paper describes the development of an equation for the design collapse strength of expanded pipe. It is based on the combination of collapse test data and theoretical modeling, and its statistical approach is fully consistent with that used for conventional OCTG described in ISO 10400 (2007). The recipe how to derive the design collapse strength of expanded pipe is also applicable to any particular pipe product that a manufacturer and an end-user may wish to qualify for well use.

Based on an example set of expanded L80 pipes, results are presented describing the collapse data using either a simple power law, or the KT collapse equation that has been recently calibrated to conventional OCTG. By adapting one parameter, the KT model can also model the collapse strength of the expanded pipe data over a range of pipe diameters, wall thicknesses and expansion ratios. The new equation takes account of the effect of internal pressure and axial load on collapse.

The API SC5 RG ET Resource Group on Expandable Tubulars is incorporating the approach presented in this paper into the draft API RP 5-EX Recommended Practice.
New Large Capacity Compact Drawworks for New Builds and Upgrade Jobs
Authors: Kverneland Hege , Moe Magne , Austefjord Arne , Kyllingstad Åge
Published: March 2008

A new drawworks using Permanent Magnet Motor Technology is being developed to make a small and compact drawworks for use on new builds and upgrade jobs. This new technology using an "inside-out" PM-motor integrated in the winch drum was first introduced to the offshore market three years ago, in a manrider winch application. The technology is now adapted to larger horsepower winches such as crane winches and drawworks. This paper will be focusing on the drawworks application reducing size and weight of the drawworks substantially compared with standard drawworks with equivalent hoisting capacity.
Dumbarton Field, UKCS: Rapid Redevelopment of a Complex, Mature North Sea Asset Using New Rotary-Steerable and Geosteering Technologies
Authors: John Ukpe , Tribe Ian , Manson Jim , Stewart Andy , Pendlebury Martin , Ferguson Emily , Melvill Kenneth , Bourgeois Daniel , Lepp Rebecca
Published: March 2008

The Dumbarton Field, operated by Maersk Oil North Sea in Block 15/20 has a number of drilling and well placement challenges, which hampered development during the 80's and 90's when operated by the previous owner. These include formation instability, directional-drilling control issues and thin complex reservoirs which are poorly imaged on seismic. Reservoir overburden is fast drilling formations with hard stringers. The field pore-pressure gradient is at 9.07ppg EMW but mud density needed for wellbore stability is greater than 11.6ppg. This resultant high overbalance and other issues such as hole cleaning, complex directional profile, ECD management at high ROPs, can lead to inefficient motor drilling. The soft formations also create limitations for push-the-bit rotary steerable systems to deliver the required directional performance to land wells.

To overcome these drilling challenges a new point-the-bit, rotary steerable system with a high dogleg capability has been utilised for successful landing of these wells into reservoir sections without need for pilot holes or mechanical sidetracks. Additionally a new LWD tool that allows monitoring of the distance and direction to formation boundaries up to 15 ft away from the wellbore has been used to proactively guide the wells along the thin oil reservoir units/sands. These tools also enabled the wells to be placed as close to the reservoir roof shales as possible to maximize stand-off from the waterleg and hence increase overall oil recovery. Distance and direction to boundary data displays are intuitive to interpretation allowing better geosteering decisions without compromising ROP and drilling efficiency.

Within six months six wells were delivered including three sidetracks (One top hole and two horizontal sections). All wells penetrated more reservoir sand than prognosed and all were drilled faster than prognosed. Initial production testing was higher than expectation.
PRD12,000 Drill Ship; Increasing Efficiency in Deep Water Operations
Authors: Fossli Børre , Hendriks Sjoerd
Published: March 2008

In the deep water environment large and expensive to operate 5th and 6th generation drilling rigs are utilized to drill exploration wells, drill development wells, perform completion activities and intervene and work over development wells. In the current market with spiraling day rates new drilling systems and improved functional specifications have been incorporated into a new build vessel of a reduced size, with improved capabilities and with functional specifications that will make drilling and work over intervention of subsea wells more efficient and cost effective against the traditional MODU.

The new vessel has the characteristics in size of an earlier generation, but the functionality of the next generation vessel.

The application areas are: Drilling subsea wells with a conventional subsea BOP and marine riser system in up to 5,000 ft water depth and ability to drill deepwater exploration wells with a split BOP and High Pressure (HP) riser system in up to 12,000 ft water depth.With a unique HP riser and split BOP, coupled with a system for Managed Pressure Drilling (MPD) particularly developed for deepwater subsea drilling, operations are enabled to cover all deepwater areas around the world.Underbalanced intervention work over and drilling performed through the same HP riser and BOP system.Motion characteristics of the vessel while in DP over a subsea well that will not compromise activities such as retrieving/landing Xmas trees or completions and/or through tubing drilling.High transit speed of 12-14 Knots for quick mobilization.

New drainage holes can be drilled with this system in mature areas often made inaccessible with conventional drilling technology due to depleted and variable formations pressure.

The drilling technology and the fit-for-purpose drilling unit combined may lead well up to 50% well cost reduction compared to 5th or 6th generation MODU's and traditional drilling methods.
Safety and Maintenance—Benefits of Applying Them Together
Authors: Lanza Mario
Published: March 2008

SYNOPSIS

The following report shows the relationship between safety and maintenance. Applying them together has resulted in the improvement of the safety conditions of the equipment, a decrease in lost working hours, and a decrease in the quantity of man-hours in hazardous jobs.

In order to maintain this improvement, these results are recorded to redesign maintenance routines and safety procedures.

Our goal is to break the paradigm that divides safety from maintenance systems and thus, we will reach our zero accidents and zero failures objective.
Multiple-Layer Completions for Efficient Treatment of Multilayer Reservoirs
Authors: Rytlewski Gary
Published: March 2008

A new method of completing multiple-layer formations has been successfully tested in the United States and Canada. This new method places sliding sleeve valves in the casing string and completes the well with normal cementing operations. The sliding sleeve valves are opened one at a time to fracture layers independently without perforating.

Completions using these casing valves are called Treat And Produce (TAP) Completions and have a unique design feature in the valves that allows a theoretically unlimited number of valves to be placed in a single well without incremental reductions to the internal diameter (ID). This near full bore feature allows normal cementing operations to be preformed with a special cement wiper plug. A control line is connected between sequential valves. When the bottom valve opens, the control line becomes pressurized and transfers the bore pressure to a piston in the valve immediately above. This piston squeezes a C-ring and makes the ID smaller. At the end of the fracture treatment to the lower valve, a dart is dropped during the flushing operation. This dart lands on the squeezed C-ring and seals the bore inside the sliding sleeve. Pressure is then increased until the next valve is pumped open. When this valve opens, the next control line is pressurized, squeezing the next C-ring.

The main feasibility issue with this cemented sliding sleeve concept was fracture initiation pressure through the cement and into the formation without perforated holes. Significant laboratory testing was conducted which predicted fracture initiation pressure to be similar to that encountered in openhole or even lower. Fracture initiation pressures were closely monitored during several field installations and confirmed that perforations were not needed to initiate fractures in the formations.

This paper describes TAP Completions, how the TAP valves work, and how the valves performed. Information on a TAP Completion with 6 layers is presented in detail and an overview of all installations to date.
H.S.E. Culture—One from Many
Authors: Crochet David , McClaine Rick , Offshore Hercules , Callen Kris
Published: March 2008

In three years, Hercules Offshore, Inc. went from a privately held company with five jack-up drilling rigs and 22 liftboats to a publicly held corporation with 73 drilling rigs, 64 liftboats, and a workboat fleet. This rapid growth has left the challenge of growing one HSE or safety culture from 10 different parts. Initially we counted on the talent of the teams with only a basic safety management system as a framework. Leaving people to do what they have always done fostered a protective or closed culture rather than the culture of open dialogue and reporting desired in a robust safety culture.

We intend to share the methodologies being currently used to grow one safety culture from many. Best practices are only a starting point. Often safety professionals attempt to grow a safety culture by adding to what is already in place, looking for more tools, and complicating the basic tools. This operates under the assumption that most understand the purpose and workings of the basic tools in their safety management system.

Our observation has been that not only have some of our tools turned into paper exercises, but many do not even get that they might be something more. We are now working under the assumption that the basic safety tools like Job Safety Analysis, Permits to Work, Time-Out and Hero (our behavioral observation tool) are not obvious. They are the building blocks of a safety management system requiring understanding. Through immersion training involving everyone, we are getting back to purpose by simplifying and streamlining, and creating belief and accountability.

Over the years we have over-complicated simple concepts. Our goal is to simplify the basic safety tools, so that when people are using them, they are using them well and for the right reasons.
Well-Integrity Issues Offshore Norway
Authors: Vignes Birgit , Aadnoy Bernt S.
Published: March 2008

A number of serious well failures in recent years led to investigations of well integrity issues. The Petroleum Safety Authority Norway (PSA) performed a "pilot well integrity survey" based on supervisory audits and requested input from 7 operating companies, 12 pre-selected offshore facilities and 406 wells. The wells were a representative selection of production and injection wells with variation both in age and development categories.

The pilot project indicates that 18% of the wells in the survey have integrity failure, issue or uncertainties and 7 % of these are shut in because of well integrity issues. The selection of wells and the companies indicate that the statistics is representative.

The well incidents in the past and the results of "pilot well integrity survey" revealed that the industry needs to increase focus on the barrier philosophy. Control of barrier status is an important SHE factor to avoid major incidents caused by e.g. unintentional leaks and well control situations. Knowledge of well integrity status at all times enables the companies to take the right actions in a proactive manner and thereby prevent incidents.

The paper presents the results and the conclusions from the pilot survey. In addition a number of technical well failures will be presented, identifying critical elements such as corrosion, leaks and operational factors. In particular, the understanding of barrier regulations, standards and implementation was found inadequate.