Net pay determination by Dempster rule of combination: Case study on Iranian offshore oil fields

International audienceNet pay detection is a key stage in reservoir characterization for several purposes: reserve estimation, reservoir modeling and simulation, production planning, etc. Determining productive zones always is simultaneous with some amount of uncertainty due to lack of enough data, insufficiency of knowledge and wild-nature of petroleum reservoirs. It becomes even more challenging in carbonates, because of their highly heterogeneous environment. Conventionally, evaluating net pays is done by applying petrophysical cutoffs on well-logs, which results in crisp classification of pay or non-pay zones. In addition, cutoff based method is developed in sandstones, and does not provide suitable results in carbonates at all. Proposed methodology of this work, Dempster-Shafer Theory, is a generalization of Bayesian Theory of conditional probabilities. Net pays are studied in two oil reservoirs by this theory; one of them is carbonate reservoir of Mishrif, the other is sandy Burgan reservoir. For validation, results 2 are compared to well tests and output of conventional cutoff method. The advantages of using Dempster-Shafer Theory, comparing to conventional cutoff based method in studying net pays is: to have a continuous fuzzy output, based on geological facts, with high generalization ability and more compatibility with well test data

Net pay determination by artificial neural network: Case study on Iranian offshore oil fields

International audienceDetermining productive zones has always been a challenge for petrophysicists. On the other hand, Artificial Neural Networks are powerful tools in solving identification problems. In this paper, pay zone determination is defined as an identification problem, and is tried to solve it by trained Neural Networks. Proposed methodology is applied on two datasets: one belongs to carbonate reservoir of Mishrif, the other belongs to sandy Burgan reservoir. The results showed high precision in classifying productive zones in predefined classes with Classification Correctness Rate of more than 85% in both geological conditions. Applicability of proposed pay zone determination procedure in carbonate environment is a great advantage of developed methodology. Fuzzified output, being independent of core tests and verification with well tests results are of other advantages of Neural Network-based method of pay zone detection

Implication of an Integrated Approach to the Determination of Water Saturation in a Carbonate Gas Reservoir Located in the Persian Gulf

Water saturation determination is one of the most important tasks in reservoir studies to predict oil and gas in place needed to be calculated with more accuracy. The estimation of this important reservoir parameter is commonly determined by various well logs data and by applying some correlations that may not be so accurate in some real practical cases, especially for carbonate reservoirs. Since laboratory core analysis data have a high accuracy, in this study, it is attempted to use core and geological core description data to present an improved method to determine an optimized cementation factor (m) and a saturation exponent (n) in order to evaluate water saturation within carbonate reservoirs compared to default values (m=2, n=2, a=1) in a carbonate gas reservoir located in the Persian Gulf. Based on integrating core petrography and velocity deviation log (VDL), core samples were classified based on the type of porosity and geology description, and then by employing log-log plots of formation resistivity factor (FRF) versus porosity and formation resistivity index (FRI) versus water saturation, saturation parameters (m,n) were determined for each classification. Utilizing default and optimized values of saturation parameters, water saturation logs were obtained through different conductivity models by employing Multi min algorithm. Then, optimized water saturation was compared to core data. Error analysis showed that water saturation data resulted in optimized saturation parameters having a lower average error of 0.08 compared to the default ones with an average error of 0.14, and based on cumulative histogram, optimized water saturation data are in good agreement with the trend of core water saturation

¿Agentes de cambio? los estudiantes del programa Pas en el departamento de Córdoba

Tesis de Maestría en SociologíaEste estudio se sitúa en la intersección entre las nociones de sociología de la educación, agencia y cambio social. La investigación busca indagar si un programa específico, el Programa Preparación para la Acciónn Social (PAS) ubicado en el departamento de Córdoba, puede mostrar indicios sobre cómo estas tres nociones interactúan en un caso particular a través de un caso de estudio de sus estudiante

Success factors for strategic change initiatives: A qualitative study of healthcare administrators\u27 perspectives

Success factors related to the implementation of change initiatives are well documented and discussed in the management literature, but they are seldom studied in healthcare organizations engaged in multiple strategic change initiatives. The purpose of this study was to identify key success factors related to implementation of change initiatives based on rich qualitative data gathered from health leader interviews at two large health systems implementing multiple change initiatives. In-depth personal interviews with 61 healthcare leaders in the two large systems were conducted and inductive qualitative analysis was employed to identify success factors associated with 13 change initiatives. Results from this analysis were compared to success factors identified in the literature, and generalizations were drawn that add significantly to the management literature, especially to that in the healthcare sector. Ten specific success factors were identified for the implementation of change initiatives. The top three success factors were (1) culture and values, (2) business processes, and (3) people and engagement. Two of the identified success factors are unique to the healthcare sector and not found in the literature on change models: service quality and client satisfaction (ranked fourth of 10) and access to information (ranked ninth). Results demonstrate the importance of human resource functions, alignment of culture and values with change, and business processes that facilitate effective communication and access to information to achieve many change initiatives. The responses also suggest opportunities for leaders of healthcare organizations to more formally recognize the degree to which various change initiatives are dependent on one another

Healthcare strategic management and the resource based view

Purpose – The purpose of this paper is to examine how two large health systems formulate and implement strategy with a specific focus on differences and similarities in the nature of strategic initiatives across systems. The aim is to gain a better understanding of the role of resource dependency theory (RDT) and resource based view (RBV) in healthcare strategic management. Design/methodology/approach – A comparative case study design is used to describe, categorize and compare strategic change initiatives within a children\u27s health and a multi-hospital system located in two competitive metropolitan markets. A total of 61 in-person semi-structured interviews with healthcare administrators were conducted during 2009. Summary statistics and qualitative content analysis were employed to examine strategic initiatives. Findings – The two health systems have as their top initiatives very similar pursuits, thus indicating that both utilize an externally oriented RDT method of strategy formulation. The relevance of the RBV becomes apparent during resource deployment for strategy implementation. The process of healthcare strategic decision-making incorporates RDT and RBV as separate and compatible activities that are sequential. Research limitations/implications – Results from this comparative case study are based on only two health systems. Further, the RBV perspective only takes managerial resources and time into consideration. Practical implications – Given that external resources are likely to become more constrained, it is important that hospitals leverage relevant internal resources, in the identification of competitive advantages and effective execution of strategic initiatives. Originality/value – The author propose a refined healthcare strategic management framework that takes both RDT and RBV into consideration by systematically linking strategy formulation with deployment of resources

Healthcare strategic management and the resource based view

Purpose – The purpose of this paper is to examine how two large health systems formulate and implement strategy with a specific focus on differences and similarities in the nature of strategic initiatives across systems. The aim is to gain a better understanding of the role of resource dependency theory (RDT) and resource based view (RBV) in healthcare strategic management. Design/methodology/approach – A comparative case study design is used to describe, categorize and compare strategic change initiatives within a children\u27s health and a multi-hospital system located in two competitive metropolitan markets. A total of 61 in-person semi-structured interviews with healthcare administrators were conducted during 2009. Summary statistics and qualitative content analysis were employed to examine strategic initiatives. Findings – The two health systems have as their top initiatives very similar pursuits, thus indicating that both utilize an externally oriented RDT method of strategy formulation. The relevance of the RBV becomes apparent during resource deployment for strategy implementation. The process of healthcare strategic decision-making incorporates RDT and RBV as separate and compatible activities that are sequential. Research limitations/implications – Results from this comparative case study are based on only two health systems. Further, the RBV perspective only takes managerial resources and time into consideration. Practical implications – Given that external resources are likely to become more constrained, it is important that hospitals leverage relevant internal resources, in the identification of competitive advantages and effective execution of strategic initiatives. Originality/value – The author propose a refined healthcare strategic management framework that takes both RDT and RBV into consideration by systematically linking strategy formulation with deployment of resources

Cohort profile update: Tehran cardiometabolic genetic study

The Tehran cardiometabolic genetic study (TCGS) is a large population-based cohort study that conducts periodic follow-ups. TCGS has created a comprehensive database comprising 20,367 participants born between 1911 and 2015 selected from four main ongoing studies in a family-based longitudinal framework. The study's primary goal is to identify the potential targets for prevention and intervention for non-communicable diseases that may develop in mid-life and late life. TCGS cohort focuses on cardiovascular, endocrine, metabolic abnormalities, cancers, and some inherited diseases. Since 2017, the TCGS cohort has augmented by encoding all health-related complications, including hospitalization outcomes and self-reports according to ICD11 coding, and verifying consanguineous marriage using genetic markers. This research provides an update on the rationale and design of the study, summarizes its findings, and outlines the objectives for precision medicine