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Sample records for reservoir architecture modeling

  1. Reservoir architecture modeling: Nonstationary models for quantitative geological characterization. Final report, April 30, 1998

    Energy Technology Data Exchange (ETDEWEB)

    Kerr, D.; Epili, D.; Kelkar, M.; Redner, R.; Reynolds, A.

    1998-12-01

    The study was comprised of four investigations: facies architecture; seismic modeling and interpretation; Markov random field and Boolean models for geologic modeling of facies distribution; and estimation of geological architecture using the Bayesian/maximum entropy approach. This report discusses results from all four investigations. Investigations were performed using data from the E and F units of the Middle Frio Formation, Stratton Field, one of the major reservoir intervals in the Gulf Coast Basin.

  2. The rudist buildup depositional model, reservoir architecture and development strategy of the cretaceous Sarvak formation of Southwest Iran

    Directory of Open Access Journals (Sweden)

    Yang Du

    2015-03-01

    Full Text Available This paper studies the lithofacies, sedimentary facies, depositional models and reservoir architecture of the rudist-bearing Sar-3 zone of Cretaceous Sarvak in the Southwest of Iran by utilizing coring, thin section, XRD data of five coring wells and 3D seismic data. Research results include the following: According to lithofacies features and their association, the rudist-mound and tidal flat are the main microfacies in the Sar-3 depositional time. By investigating the regional tectonic setting and seismic interpretation, a depositional model was built for the Sar-3 zone, which highlights four key points: 1 The distribution of the rudist-buildup is controlled by the paleo-high. 2 The build-up outside of the wide colonize stage but reached the wave-base level in a short time by regression and formation uplift, and was destroyed by the high energy current, then forming the moundy allochthonous deposition after being dispersed and redeposited. 3 The tidal flat develops widely in the upper Sar-3, and the deposition thickness depends on the paleo-structure. The tidal channel develops in the valley and fringe of the Paleo-structure. 4 The exposure within the leaching effect by the meteoric water of the top of Sar-3 is the main controlling factor of the reservoir vertical architecture. The Sar-3 zone featured as the dualistic architecture consists of two regions: the lower is the rudist reef limestone reservoir and the upper is the tidal condense limestone interlayer. The thickness of each is controlled by the paleo-structure. The Paleo-high zone is the preferential development zone. Based on reservoir characteristics of the different zones, a targeted development strategy has been proposed. Keeping the trajectory in the middle of the oil-layer in the paleo-high, and in the paleo-low, make the trajectory crossing the oil-zone and then keep it in the lower.

  3. Modeling Architectural Patterns Using Architectural Primitives

    NARCIS (Netherlands)

    Zdun, Uwe; Avgeriou, Paris

    2005-01-01

    Architectural patterns are a key point in architectural documentation. Regrettably, there is poor support for modeling architectural patterns, because the pattern elements are not directly matched by elements in modeling languages, and, at the same time, patterns support an inherent variability that

  4. Modeling Architectural Patterns Using Architectural Primitives

    NARCIS (Netherlands)

    Zdun, Uwe; Avgeriou, Paris

    2005-01-01

    Architectural patterns are a key point in architectural documentation. Regrettably, there is poor support for modeling architectural patterns, because the pattern elements are not directly matched by elements in modeling languages, and, at the same time, patterns support an inherent variability that

  5. Modeling Architectural Patterns' Behavior Using Architectural Primitives

    NARCIS (Netherlands)

    Kamal, Ahmad Waqas; Avgeriou, Paris; Morrison, R; Balasubramaniam, D; Falkner, K

    2008-01-01

    Architectural patterns have an impact on both the structure and the behavior of a system at the architecture design level. However, it is challenging to model patterns' behavior in a systematic way because modeling languages do not provide the appropriate abstractions and because each pattern

  6. Modeling Architectural Patterns’ Behavior Using Architectural Primitives

    NARCIS (Netherlands)

    Waqas Kamal, Ahmad; Avgeriou, Paris

    2008-01-01

    Architectural patterns have an impact on both the structure and the behavior of a system at the architecture design level. However, it is challenging to model patterns’ behavior in a systematic way because modeling languages do not provide the appropriate abstractions and because each pattern

  7. Comparing root architectural models

    Science.gov (United States)

    Schnepf, Andrea; Javaux, Mathieu; Vanderborght, Jan

    2017-04-01

    Plant roots play an important role in several soil processes (Gregory 2006). Root architecture development determines the sites in soil where roots provide input of carbon and energy and take up water and solutes. However, root architecture is difficult to determine experimentally when grown in opaque soil. Thus, root architectural models have been widely used and been further developed into functional-structural models that are able to simulate the fate of water and solutes in the soil-root system (Dunbabin et al. 2013). Still, a systematic comparison of the different root architectural models is missing. In this work, we focus on discrete root architecture models where roots are described by connected line segments. These models differ (a) in their model concepts, such as the description of distance between branches based on a prescribed distance (inter-nodal distance) or based on a prescribed time interval. Furthermore, these models differ (b) in the implementation of the same concept, such as the time step size, the spatial discretization along the root axes or the way stochasticity of parameters such as root growth direction, growth rate, branch spacing, branching angles are treated. Based on the example of two such different root models, the root growth module of R-SWMS and RootBox, we show the impact of these differences on simulated root architecture and aggregated information computed from this detailed simulation results, taking into account the stochastic nature of those models. References Dunbabin, V.M., Postma, J.A., Schnepf, A., Pagès, L., Javaux, M., Wu, L., Leitner, D., Chen, Y.L., Rengel, Z., Diggle, A.J. Modelling root-soil interactions using three-dimensional models of root growth, architecture and function (2013) Plant and Soil, 372 (1-2), pp. 93 - 124. Gregory (2006) Roots, rhizosphere and soil: the route to a better understanding of soil science? European Journal of Soil Science 57: 2-12.

  8. High resolution reservoir geological modelling using outcrop information

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Changmin; Lin Kexiang; Liu Huaibo [Jianghan Petroleum Institute, Hubei (China)] [and others

    1997-08-01

    This is China`s first case study of high resolution reservoir geological modelling using outcrop information. The key of the modelling process is to build a prototype model and using the model as a geological knowledge bank. Outcrop information used in geological modelling including seven aspects: (1) Determining the reservoir framework pattern by sedimentary depositional system and facies analysis; (2) Horizontal correlation based on the lower and higher stand duration of the paleo-lake level; (3) Determining the model`s direction based on the paleocurrent statistics; (4) Estimating the sandbody communication by photomosaic and profiles; (6) Estimating reservoir properties distribution within sandbody by lithofacies analysis; and (7) Building the reservoir model in sandbody scale by architectural element analysis and 3-D sampling. A high resolution reservoir geological model of Youshashan oil field has been built by using this method.

  9. Consistent model driven architecture

    Science.gov (United States)

    Niepostyn, Stanisław J.

    2015-09-01

    The goal of the MDA is to produce software systems from abstract models in a way where human interaction is restricted to a minimum. These abstract models are based on the UML language. However, the semantics of UML models is defined in a natural language. Subsequently the verification of consistency of these diagrams is needed in order to identify errors in requirements at the early stage of the development process. The verification of consistency is difficult due to a semi-formal nature of UML diagrams. We propose automatic verification of consistency of the series of UML diagrams originating from abstract models implemented with our consistency rules. This Consistent Model Driven Architecture approach enables us to generate automatically complete workflow applications from consistent and complete models developed from abstract models (e.g. Business Context Diagram). Therefore, our method can be used to check practicability (feasibility) of software architecture models.

  10. Avionics Architecture Modelling Language

    Science.gov (United States)

    Alana, Elena; Naranjo, Hector; Valencia, Raul; Medina, Alberto; Honvault, Christophe; Rugina, Ana; Panunzia, Marco; Dellandrea, Brice; Garcia, Gerald

    2014-08-01

    This paper presents the ESA AAML (Avionics Architecture Modelling Language) study, which aimed at advancing the avionics engineering practices towards a model-based approach by (i) identifying and prioritising the avionics-relevant analyses, (ii) specifying the modelling language features necessary to support the identified analyses, and (iii) recommending/prototyping software tooling to demonstrate the automation of the selected analyses based on a modelling language and compliant with the defined specification.

  11. Architecture of deep-water reservoirs; Arquitetura de reservatorios de aguas profundas

    Energy Technology Data Exchange (ETDEWEB)

    Moraes, Marco Antonio Schreiner [PETROBRAS S.A., Rio de de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES). Gerencia de Sedimentologia e Petrologia], E-mail: masmoraes@petrobras.com.br; Blaskovski, Paulo Roberto; Paraizo, Paulo Lopes Brandao

    2005-11-15

    the main reservoirs of fields like Namorado, Carapeba, Roncador, Jubarte, among others. In the upper Tertiary (Oligocene-Miocene), where salt tectonics generated a mini-basin morphology, large lobe complexes are found in fields like Marlim, Marlim Sul, and others. The recognition and differentiation of the different reservoir architectural styles is useful to collect and organize information about the reservoir external geometry and internal heterogeneities, to guide the construction of three-dimensional models, and to orient reservoir management. (author)

  12. Integrated Sedimentological Approach to Assess Reservoir Quality and Architecture of Khuff Carbonates: Outcrop Analog, Central Saudi Arabia

    Science.gov (United States)

    Osman, Mutsim; Abdullatif, Osman

    2017-04-01

    The Permian to Triassic Khuff carbonate reservoirs (and equivalents) in the Middle East are estimated to contain about 38.4% of the world's natural gas reserves. Excellent exposed outcrops in central Saudi Arabia provide good outcrop equivalents to subsurface Khuff reservoirs. This study conduct high resolution outcrop scale investigations on an analog reservoir for upper Khartam of Khuff Formation. The main objective is to reconstruct litho- and chemo- stratigraphic outcrop analog model that may serve to characterize reservoir high resolution (interwell) heterogeneity, continuity and architecture. Given the fact of the limitation of subsurface data and toolsin capturing interwell reservoir heterogeneity, which in turn increases the value of this study.The methods applied integrate sedimentological, stratigraphic petrographic, petrophysical data and chemical analyses for major, trace and rare earth elements. In addition, laser scanning survey (LIDAR) was also utilized in this study. The results of the stratigraphic investigations revealed that the lithofacies range from mudstone, wackestone, packestone and grainstone. These lithofacies represent environments ranging from supratidal, intertidal, subtidal and shoal complex. Several meter-scale and less high resolution sequences and composite sequences within 4th and 5th order cycles were also recognized in the outcrop analog. The lithofacies and architectural analysis revealed several vertically and laterally stacked sequences at the outcrop as revealed from the stratigraphic sections and the lidar scan. Chemostratigraphy is effective in identifying lithofacies and sequences within the outcrop analog. Moreover, different chemical signatures were also recognized and allowed establishing and correlating high resolution lithofacies, reservoir zones, layers and surfaces bounding reservoirs and non-reservoir zones at scale of meters or less. The results of this high resolution outcrop analog study might help to understand

  13. Petroleum reservoir data for testing simulation models

    Energy Technology Data Exchange (ETDEWEB)

    Lloyd, J.M.; Harrison, W.

    1980-09-01

    This report consists of reservoir pressure and production data for 25 petroleum reservoirs. Included are 5 data sets for single-phase (liquid) reservoirs, 1 data set for a single-phase (liquid) reservoir with pressure maintenance, 13 data sets for two-phase (liquid/gas) reservoirs and 6 for two-phase reservoirs with pressure maintenance. Also given are ancillary data for each reservoir that could be of value in the development and validation of simulation models. A bibliography is included that lists the publications from which the data were obtained.

  14. A reservoir simulation approach for modeling of naturally fractured reservoirs

    Directory of Open Access Journals (Sweden)

    H. Mohammadi

    2012-12-01

    Full Text Available In this investigation, the Warren and Root model proposed for the simulation of naturally fractured reservoir was improved. A reservoir simulation approach was used to develop a 2D model of a synthetic oil reservoir. Main rock properties of each gridblock were defined for two different types of gridblocks called matrix and fracture gridblocks. These two gridblocks were different in porosity and permeability values which were higher for fracture gridblocks compared to the matrix gridblocks. This model was solved using the implicit finite difference method. Results showed an improvement in the Warren and Root model especially in region 2 of the semilog plot of pressure drop versus time, which indicated a linear transition zone with no inflection point as predicted by other investigators. Effects of fracture spacing, fracture permeability, fracture porosity, matrix permeability and matrix porosity on the behavior of a typical naturally fractured reservoir were also presented.

  15. Modeling vapor dominated geothermal reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Marconcini, R.; McEdwards, D.; Neri, G.; Ruffilli, C.; Schroeder, R.; Weres, O.; Witherspoon, P.

    1977-09-12

    The unresolved questions with regard to vapor-dominated reservoir production and longevity are reviewed. The simulation of reservoir behavior and the LBL computer program are discussed. The geology of Serrazzano geothermal field and its reservoir simulation are described. (MHR)

  16. Analysis of real-time reservoir monitoring : reservoirs, strategies, & modeling.

    Energy Technology Data Exchange (ETDEWEB)

    Mani, Seethambal S.; van Bloemen Waanders, Bart Gustaaf; Cooper, Scott Patrick; Jakaboski, Blake Elaine; Normann, Randy Allen; Jennings, Jim (University of Texas at Austin, Austin, TX); Gilbert, Bob (University of Texas at Austin, Austin, TX); Lake, Larry W. (University of Texas at Austin, Austin, TX); Weiss, Chester Joseph; Lorenz, John Clay; Elbring, Gregory Jay; Wheeler, Mary Fanett (University of Texas at Austin, Austin, TX); Thomas, Sunil G. (University of Texas at Austin, Austin, TX); Rightley, Michael J.; Rodriguez, Adolfo (University of Texas at Austin, Austin, TX); Klie, Hector (University of Texas at Austin, Austin, TX); Banchs, Rafael (University of Texas at Austin, Austin, TX); Nunez, Emilio J. (University of Texas at Austin, Austin, TX); Jablonowski, Chris (University of Texas at Austin, Austin, TX)

    2006-11-01

    The project objective was to detail better ways to assess and exploit intelligent oil and gas field information through improved modeling, sensor technology, and process control to increase ultimate recovery of domestic hydrocarbons. To meet this objective we investigated the use of permanent downhole sensors systems (Smart Wells) whose data is fed real-time into computational reservoir models that are integrated with optimized production control systems. The project utilized a three-pronged approach (1) a value of information analysis to address the economic advantages, (2) reservoir simulation modeling and control optimization to prove the capability, and (3) evaluation of new generation sensor packaging to survive the borehole environment for long periods of time. The Value of Information (VOI) decision tree method was developed and used to assess the economic advantage of using the proposed technology; the VOI demonstrated the increased subsurface resolution through additional sensor data. Our findings show that the VOI studies are a practical means of ascertaining the value associated with a technology, in this case application of sensors to production. The procedure acknowledges the uncertainty in predictions but nevertheless assigns monetary value to the predictions. The best aspect of the procedure is that it builds consensus within interdisciplinary teams The reservoir simulation and modeling aspect of the project was developed to show the capability of exploiting sensor information both for reservoir characterization and to optimize control of the production system. Our findings indicate history matching is improved as more information is added to the objective function, clearly indicating that sensor information can help in reducing the uncertainty associated with reservoir characterization. Additional findings and approaches used are described in detail within the report. The next generation sensors aspect of the project evaluated sensors and packaging

  17. A catalog of architectural primitives for modeling architectural patterns

    NARCIS (Netherlands)

    Zdun, Uwe; Avgeriou, Paris

    Architectural patterns are a fundamental aspect of the architecting process and subsequently the architectural documentation. Unfortunately, there is only poor support for modeling architectural patterns for two reasons. First, patterns describe recurring design solutions and hence do not directly

  18. Modeling Reservoir-River Networks in Support of Optimizing Seasonal-Scale Reservoir Operations

    Science.gov (United States)

    Villa, D. L.; Lowry, T. S.; Bier, A.; Barco, J.; Sun, A.

    2011-12-01

    each timestep and minimize computational overhead. Power generation for each reservoir is estimated using a 2-dimensional regression that accounts for both the available head and turbine efficiency. The object-oriented architecture makes run configuration easy to update. The dynamic model inputs include inflow and meteorological forecasts while static inputs include bathymetry data, reservoir and power generation characteristics, and topological descriptors. Ensemble forecasts of hydrological and meteorological conditions are supplied in real-time by Pacific Northwest National Laboratory and are used as a proxy for uncertainty, which is carried through the simulation and optimization process to produce output that describes the probability that different operational scenario's will be optimal. The full toolset, which includes HydroSCOPE, is currently being tested on the Feather River system in Northern California and the Upper Colorado Storage Project.

  19. Digital Architecture Planning Model

    Energy Technology Data Exchange (ETDEWEB)

    Oxstrand, Johanna Helene [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS); Al Rashdan, Ahmad Yahya Mohammad [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS); Bly, Aaron Douglas [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS); Rice, Brandon Charles [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS); Fitzgerald, Kirk [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS); Wilson, Keith Leon [Idaho National Lab. (INL), Idaho Falls, ID (United States). Light Water Reactor Sustainability Program (LWRS)

    2016-03-01

    As part of the U.S. Department of Energy’s Light Water Reactor Sustainability Program, the Digital Architecture (DA) Project focuses on providing a model that nuclear utilities can refer to when planning deployment of advanced technologies. The digital architecture planning model (DAPM) is the methodology for mapping power plant operational and support activities into a DA that unifies all data sources needed by the utilities to operate their plants. The DA is defined as a collection of information technology capabilities needed to support and integrate a wide spectrum of real-time digital capabilities for performance improvements of nuclear power plants. DA can be thought of as integration of the separate instrumentation and control and information systems already in place in nuclear power plants, which are brought together for the purpose of creating new levels of automation in plant work activities. A major objective in DAPM development was to survey all key areas that needed to be reviewed in order for a utility to make knowledgeable decisions regarding needs and plans to implement a DA at the plant. The development was done in two steps. First, researchers surveyed the nuclear industry in order to learn their near-term plans for adopting new advanced capabilities and implementing a network (i.e., wireless and wire) infrastructure throughout the plant, including the power block. Secondly, a literature review covering regulatory documents, industry standards, and technical research reports and articles was conducted. The objective of the review was to identify key areas to be covered by the DAPM, which included the following: 1. The need for a DA and its benefits to the plant 2. Resources required to implement the DA 3. Challenges that need to be addressed and resolved to implement the DA 4. Roles and responsibilities of the DA implementation plan. The DAPM was developed based on results from the survey and the literature review. Model development, including

  20. Study on fine geological modelling of the fluvial sandstone reservoir in Daqing oilfield

    Energy Technology Data Exchange (ETDEWEB)

    Zhoa Han-Qing [Daqing Research Institute, Helongjiang (China)

    1997-08-01

    These paper aims at developing a method for fine reservoir description in maturing oilfields by using close spaced well logging data. The main productive reservoirs in Daqing oilfield is a set of large fluvial-deltaic deposits in the Songliao Lake Basin, characterized by multi-layers and serious heterogeneities. Various fluvial channel sandstone reservoirs cover a fairly important proportion of reserves. After a long period of water flooding, most of them have turned into high water cut layers, but there are considerable residual reserves within them, which are difficult to find and tap. Making fine reservoir description and developing sound a geological model is essential for tapping residual oil and enhancing oil recovery. The principal reason for relative lower precision of predicting model developed by using geostatistics is incomplete recognition of complex distribution of fluvial reservoirs and their internal architecture`s. Tasking advantage of limited outcrop data from other regions (suppose no outcrop data available in oilfield) can only provide the knowledge of subtle changing of reservoir parameters and internal architecture. For the specific geometry distribution and internal architecture of subsurface reservoirs (such as in produced regions) can be gained only from continuous infilling logging well data available from studied areas. For developing a geological model, we think the first important thing is to characterize sandbodies geometries and their general architecture`s, which are the framework of models, and then the slight changing of interwell parameters and internal architecture`s, which are the contents and cells of the model. An excellent model should possess both of them, but the geometry is the key to model, because it controls the contents and cells distribution within a model.

  1. Behavior models for software architecture

    OpenAIRE

    Auguston, Mikhail

    2014-01-01

    Approved for public release; distribution is unlimited. Approved for public release; distribution is unlimited Monterey Phoenix (MP) is an approach to formal software system architecture specification based on behavior models. Architecture modeling focuses not only on the activities and interactions within the system, but also on the interactions between the system and its environment, providing an abstraction for interaction specification. The behavior of the system is defined as a set...

  2. Reservoir management under geological uncertainty using fast model update

    NARCIS (Netherlands)

    Hanea, R.; Evensen, G.; Hustoft, L.; Ek, T.; Chitu, A.; Wilschut, F.

    2015-01-01

    Statoil is implementing "Fast Model Update (FMU)," an integrated and automated workflow for reservoir modeling and characterization. FMU connects all steps and disciplines from seismic depth conversion to prediction and reservoir management taking into account relevant reservoir uncertainty. FMU del

  3. Lithological architecture, geological processes and energy-field environments are major factors for the formation of hydrocarbon reservoirs

    Institute of Scientific and Technical Information of China (English)

    ZHAO Wenzhi; WANG Zecheng; LI Xiaoqing; WANG Hongjun; WANG Zhaoyun

    2005-01-01

    The formation of hydrocarbon reservoirs is controlled by three major factors: lithological architecture, geological processes and energy-field environments. Among the three major factors, lithological architecture provides the storing medium for hydrocarbon; geological processes include hydrocarbon generation, migration, accumulation, preservation and modification; and energy-field environments refer to the various geothermal and geodynamic forces that affect the lithological architecture and drive the geological processes.In this study, we take Kela-2 and Sulige gas reservoirs as two examples to study relationships among the three major factors, and explain how these factors influence the scale and quality of hydrocarbon reservoirs.

  4. Physical modelling of the Akkajaure reservoir

    Directory of Open Access Journals (Sweden)

    J. Sahlberg

    2003-01-01

    Full Text Available This paper describes the seasonal temperature development in the Akkajaure reservoir, one of the largest Swedish reservoirs. It lies in the headwaters of the river Lulealven in northern Sweden; it is 60 km long and 5 km wide with a maximum depth of 92 m. The maximum allowed variation in surface water level is 30 m. The temperature field in the reservoir is important for many biochemical processes. A one-dimensional lake model of the Akkajaure reservoir is developed from a lake model by Sahlberg (1983 and 1988. The dynamic eddy viscosity is calculated by a two equation turbulence model, a k–ε model and the hypolimnic eddy diffusivity formulation which is a function of the stability frequency (Hondzo et al., 1993. A comparison between calculated and measured temperature profiles showed a maximum discrepancy of 0.5–1.0°C over the period 1999-2002. Except for a few days in summer, the water temperature is vertically homogeneous. Over that period of years, a weak stratification of temperature occurred on only one to two weeks a year on different dates in July and August. This will have biological consequences. Keywords: temperature profile,reservoir, 1-D lake model, stratification, Sweden

  5. HRST architecture modeling and assessments

    Science.gov (United States)

    Comstock, Douglas A.

    1997-01-01

    This paper presents work supporting the assessment of advanced concept options for the Highly Reusable Space Transportation (HRST) study. It describes the development of computer models as the basis for creating an integrated capability to evaluate the economic feasibility and sustainability of a variety of system architectures. It summarizes modeling capabilities for use on the HRST study to perform sensitivity analysis of alternative architectures (consisting of different combinations of highly reusable vehicles, launch assist systems, and alternative operations and support concepts) in terms of cost, schedule, performance, and demand. In addition, the identification and preliminary assessment of alternative market segments for HRST applications, such as space manufacturing, space tourism, etc., is described. Finally, the development of an initial prototype model that can begin to be used for modeling alternative HRST concepts at the system level is presented.

  6. A MATHEMATICAL MODEL OF RESERVOIR SEDIMENTATION

    Institute of Scientific and Technical Information of China (English)

    HUANG Jinchi

    2001-01-01

    Reliable quantitative estimation of bed aggradation or degradation is important for river-training and water management projects. With the development of water resources, sediment problems associated with a dam are becoming more severe. This paper describes some special problems in mathematical model for calculation of degradation and aggradation in a reservoir. The main efforts of this study are on the treatment of some physical processes of fine sediment transport (<0.05 mm). Problems in a reservoir are obviously different from a natural stream, such as the turbid current flow, orifice sediment flushing;and the initiation and consolidation of cohesive sediment deposition. The case of Liujiaxia Reservoir,which is located in the upper reaches of the Yellow River, is employed to verify the model. The results show that the model is applicable in the evaluation of an engineering planing with plenty of fine sediment movement.

  7. Architectural Design Document for Camera Models

    DEFF Research Database (Denmark)

    Thuesen, Gøsta

    1998-01-01

    Architecture of camera simulator models and data interface for the Maneuvering of Inspection/Servicing Vehicle (MIV) study.......Architecture of camera simulator models and data interface for the Maneuvering of Inspection/Servicing Vehicle (MIV) study....

  8. Architectural Design Document for Camera Models

    DEFF Research Database (Denmark)

    Thuesen, Gøsta

    1998-01-01

    Architecture of camera simulator models and data interface for the Maneuvering of Inspection/Servicing Vehicle (MIV) study.......Architecture of camera simulator models and data interface for the Maneuvering of Inspection/Servicing Vehicle (MIV) study....

  9. Connectivity of channelized reservoirs: a modelling approach

    Energy Technology Data Exchange (ETDEWEB)

    Larue, David K. [ChevronTexaco, Bakersfield, CA (United States); Hovadik, Joseph [ChevronTexaco, San Ramon, CA (United States)

    2006-07-01

    Connectivity represents one of the fundamental properties of a reservoir that directly affects recovery. If a portion of the reservoir is not connected to a well, it cannot be drained. Geobody or sandbody connectivity is defined as the percentage of the reservoir that is connected, and reservoir connectivity is defined as the percentage of the reservoir that is connected to wells. Previous studies have mostly considered mathematical, physical and engineering aspects of connectivity. In the current study, the stratigraphy of connectivity is characterized using simple, 3D geostatistical models. Based on these modelling studies, stratigraphic connectivity is good, usually greater than 90%, if the net: gross ratio, or sand fraction, is greater than about 30%. At net: gross values less than 30%, there is a rapid diminishment of connectivity as a function of net: gross. This behaviour between net: gross and connectivity defines a characteristic 'S-curve', in which the connectivity is high for net: gross values above 30%, then diminishes rapidly and approaches 0. Well configuration factors that can influence reservoir connectivity are well density, well orientation (vertical or horizontal; horizontal parallel to channels or perpendicular) and length of completion zones. Reservoir connectivity as a function of net: gross can be improved by several factors: presence of overbank sandy facies, deposition of channels in a channel belt, deposition of channels with high width/thickness ratios, and deposition of channels during variable floodplain aggradation rates. Connectivity can be reduced substantially in two-dimensional reservoirs, in map view or in cross-section, by volume support effects and by stratigraphic heterogeneities. It is well known that in two dimensions, the cascade zone for the 'S-curve' of net: gross plotted against connectivity occurs at about 60% net: gross. Generalizing this knowledge, any time that a reservoir can be regarded as &apos

  10. Modeling Transport of Flushed Reservoir Sediment

    Science.gov (United States)

    Dubinski, I. M.

    2014-12-01

    Drawdown flushing of a reservoir is often part of a reservoir sediment management program. Flushing can deliver higher than normal sediment loads to the river channel located downstream of a reservoir. The flushed sediment may contain a higher proportion of finer sediment than what was delivered to a channel prior to the presence of the reservoir. The extent of long-term impacts caused by the flushed sediment on the channel morphology and habitat will in part depend on the residence time of the sediment within the channel. In this study we used MIKE 21C to model the fate of flushed sediment through a river channel where the bed material consists of an armoring layer of gravels overlying finer sediment. MIKE 21C is a two-dimensional curvilinear morphological model for rivers developed by DHI. Curvilinear means that the model grid may curve to better follow the channel and flow direction, for example in a meandering channel. Multiple bed material layers are included in the model to represent the armoring and underlying layers existing in the bed separately from the overlying flushed sediment. These layers may also mix. The nature of the interactions between these two layers helps regulate transport and deposition of the flushed sediment, thus are critical to assessing the fate of the flushed sediment and associated potential impacts.

  11. An architecture for integration of multidisciplinary models

    DEFF Research Database (Denmark)

    Belete, Getachew F.; Voinov, Alexey; Holst, Niels

    2014-01-01

    , Enterprise Application Integration, and Integration Design Patterns. We developed an architecture of a multidisciplinary model integration framework that brings these three aspects of integration together. Service-oriented-based platform independent architecture that enables to establish loosely coupled...

  12. On learning navigation behaviors for small mobile robots with reservoir computing architectures.

    Science.gov (United States)

    Antonelo, Eric Aislan; Schrauwen, Benjamin

    2015-04-01

    This paper proposes a general reservoir computing (RC) learning framework that can be used to learn navigation behaviors for mobile robots in simple and complex unknown partially observable environments. RC provides an efficient way to train recurrent neural networks by letting the recurrent part of the network (called reservoir) be fixed while only a linear readout output layer is trained. The proposed RC framework builds upon the notion of navigation attractor or behavior that can be embedded in the high-dimensional space of the reservoir after learning. The learning of multiple behaviors is possible because the dynamic robot behavior, consisting of a sensory-motor sequence, can be linearly discriminated in the high-dimensional nonlinear space of the dynamic reservoir. Three learning approaches for navigation behaviors are shown in this paper. The first approach learns multiple behaviors based on the examples of navigation behaviors generated by a supervisor, while the second approach learns goal-directed navigation behaviors based only on rewards. The third approach learns complex goal-directed behaviors, in a supervised way, using a hierarchical architecture whose internal predictions of contextual switches guide the sequence of basic navigation behaviors toward the goal.

  13. Reservoir

    Directory of Open Access Journals (Sweden)

    M. Mokhtar

    2016-12-01

    Full Text Available Scarab field is an analog for the deep marine slope channels in Nile Delta of Egypt. It is one of the Pliocene reservoirs in West delta deep marine concession. Channel-1 and channel-2 are considered as main channels of Scarab field. FMI log is used for facies classification and description of the channel subsequences. Core data analysis is integrated with FMI to confirm the lithologic response and used as well for describing the reservoir with high resolution. A detailed description of four wells penetrated through both channels lead to define channel sequences. Some of these sequences are widely extended within the field under study exhibiting a good correlation between the wells. Other sequences were of local distribution. Lithologic sequences are characterized mainly by fining upward in Vshale logs. The repetition of these sequences reflects the stacking pattern and high heterogeneity of the sandstone reservoir. It also refers to the sea level fluctuation which has a direct influence to the facies change. In terms of integration of the previously described sequences with a high resolution seismic data a depositional model has been established. The model defines different stages of the channel using Scarab-2 well as an ideal analog.

  14. Reservoir pressure evolution model during exploration drilling

    Directory of Open Access Journals (Sweden)

    Korotaev B. A.

    2017-03-01

    Full Text Available Based on the analysis of laboratory studies and literature data the method for estimating reservoir pressure in exploratory drilling has been proposed, it allows identify zones of abnormal reservoir pressure in the presence of seismic data on reservoir location depths. This method of assessment is based on developed at the end of the XX century methods using d- and σ-exponentials taking into account the mechanical drilling speed, rotor speed, bit load and its diameter, lithological constant and degree of rocks' compaction, mud density and "regional density". It is known that in exploratory drilling pulsation of pressure at the wellhead is observed. Such pulsation is a consequence of transferring reservoir pressure through clay. In the paper the mechanism for transferring pressure to the bottomhole as well as the behaviour of the clay layer during transmission of excess pressure has been described. A laboratory installation has been built, it has been used for modelling pressure propagation to the bottomhole of the well through a layer of clay. The bulge of the clay layer is established for 215.9 mm bottomhole diameter. Functional correlation of pressure propagation through the layer of clay has been determined and a reaction of the top clay layer has been shown to have bulge with a height of 25 mm. A pressure distribution scheme (balance has been developed, which takes into account the distance from layers with abnormal pressure to the bottomhole. A balance equation for reservoir pressure evaluation has been derived including well depth, distance from bottomhole to the top of the formation with abnormal pressure and density of clay.

  15. Development of Reservoir Characterization Techniques and Production Models for Exploiting Naturally Fractured Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Wiggins, Michael L.; Brown, Raymon L.; Civan, Frauk; Hughes, Richard G.

    2001-08-15

    Research continues on characterizing and modeling the behavior of naturally fractured reservoir systems. Work has progressed on developing techniques for estimating fracture properties from seismic and well log data, developing naturally fractured wellbore models, and developing a model to characterize the transfer of fluid from the matrix to the fracture system for use in the naturally fractured reservoir simulator.

  16. Entropy-based consistent model driven architecture

    Science.gov (United States)

    Niepostyn, Stanisław Jerzy

    2016-09-01

    A description of software architecture is a plan of the IT system construction, therefore any architecture gaps affect the overall success of an entire project. The definitions mostly describe software architecture as a set of views which are mutually unrelated, hence potentially inconsistent. Software architecture completeness is also often described in an ambiguous way. As a result most methods of IT systems building comprise many gaps and ambiguities, thus presenting obstacles for software building automation. In this article the consistency and completeness of software architecture are mathematically defined based on calculation of entropy of the architecture description. Following this approach, in this paper we also propose our method of automatic verification of consistency and completeness of the software architecture development method presented in our previous article as Consistent Model Driven Architecture (CMDA). The proposed FBS (Functionality-Behaviour-Structure) entropy-based metric applied in our CMDA approach enables IT architects to decide whether the modelling process is complete and consistent. With this metric, software architects could assess the readiness of undergoing modelling work for the start of IT system building. It even allows them to assess objectively whether the designed software architecture of the IT system could be implemented at all. The overall benefit of such an approach is that it facilitates the preparation of complete and consistent software architecture more effectively as well as it enables assessing and monitoring of the ongoing modelling development status. We demonstrate this with a few industry examples of IT system designs.

  17. Spatial Stochastic Point Models for Reservoir Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Syversveen, Anne Randi

    1997-12-31

    The main part of this thesis discusses stochastic modelling of geology in petroleum reservoirs. A marked point model is defined for objects against a background in a two-dimensional vertical cross section of the reservoir. The model handles conditioning on observations from more than one well for each object and contains interaction between objects, and the objects have the correct length distribution when penetrated by wells. The model is developed in a Bayesian setting. The model and the simulation algorithm are demonstrated by means of an example with simulated data. The thesis also deals with object recognition in image analysis, in a Bayesian framework, and with a special type of spatial Cox processes called log-Gaussian Cox processes. In these processes, the logarithm of the intensity function is a Gaussian process. The class of log-Gaussian Cox processes provides flexible models for clustering. The distribution of such a process is completely characterized by the intensity and the pair correlation function of the Cox process. 170 refs., 37 figs., 5 tabs.

  18. Triple Medium Physical Model of Post Fracturing High-Rank Coal Reservoir in Southern Qinshui Basin

    Institute of Scientific and Technical Information of China (English)

    Shiqi Liu; Shuxun Sang; Qipeng Zhu; Jiefang Zhang; Hefeng Gao; Huihu Liu; Lixing Lin

    2015-01-01

    In this paper, influences on the reservoir permeability, the reservoir architecture and the fluid flow pattern caused by hydraulic fracturing are analyzed. Based on the structure and production fluid flow model of post fracturing high-rank coal reservoir, Warren-Root Model is improved. A new physical model that is more suitable for post fracturing high-rank coal reser-voir is established. The results show that the width, the flow conductivity and the permeability of hydraulic fractures are much larger than natural fractures in coal bed reservoir. Hydraulic frac-ture changes the flow pattern of gas and flow channel to wellbore, thus should be treated as an independent medium. Warrant-Root Model has some limitations and can’t give a comprehensive interpretation of seepage mechanism in post fracturing high-rank coal reservoir. Modified War-rant-Root Model simplifies coal bed reservoir to an ideal system with hydraulic fracture, ortho-gonal macroscopic fracture and cuboid matrix. Hydraulic fracture is double wing, vertical and symmetric to wellbore. Coal bed reservoir is divided into cuboids by hydraulic fracture and fur-ther by macroscopic fractures. Flow behaviors in coal bed reservoir are simplified to three step flows of gas and two step flows of water. The swap mode of methane between coal matrix and macroscopic fractures is pseudo steady fluid channeling. The flow behaviors of methane to well-bore no longer follow Darcy’s Law and are mainly affected by inertia force. The flow pattern of water follows Darcy’s Law. The new physical model is more suitable for post fracturing high-rank coal reservoir.

  19. An Architectural Model for Component Groupware

    NARCIS (Netherlands)

    Farias, de Clever R.G.; Goncalves, Carlos E.; Rosatelli, Marta C.; Ferreira Pires, Luis; Sinderen, van Marten; Fuks, Hugo; Lukosch, Stephan; Salgado, Ana Carolina

    2005-01-01

    This paper proposes an architectural model to facilitate the design of component-based groupware systems. This architectural model has been defined based on (1) three pre-defined component types, (2) a refinement strategy that relies on these component types, (3) the identification of layers of coll

  20. Relating business modelling and enterprise architecture

    NARCIS (Netherlands)

    Meertens, Lucas Onno

    2013-01-01

    This thesis proposes a methodology for creating business models, evaluating them, and relating them to enterprise architecture. The methodology consists of several steps, leading from an organization’s current situation to a target situation, via business models and enterprise architecture. Current

  1. Relating business modelling and enterprise architecture

    NARCIS (Netherlands)

    Meertens, Lucas Onno

    2013-01-01

    This thesis proposes a methodology for creating business models, evaluating them, and relating them to enterprise architecture. The methodology consists of several steps, leading from an organization’s current situation to a target situation, via business models and enterprise architecture.

  2. Model Construct Based Enterprise Model Architecture and Its Modeling Approach

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In order to support enterprise integration, a kind of model construct based enterprise model architecture and its modeling approach are studied in this paper. First, the structural makeup and internal relationships of enterprise model architecture are discussed. Then, the concept of reusable model construct (MC) which belongs to the control view and can help to derive other views is proposed. The modeling approach based on model construct consists of three steps, reference model architecture synthesis, enterprise model customization, system design and implementation. According to MC based modeling approach a case study with the background of one-kind-product machinery manufacturing enterprises is illustrated. It is shown that proposal model construct based enterprise model architecture and modeling approach are practical and efficient.

  3. Statistical modeling of geopressured geothermal reservoirs

    Science.gov (United States)

    Ansari, Esmail; Hughes, Richard; White, Christopher D.

    2017-06-01

    Identifying attractive candidate reservoirs for producing geothermal energy requires predictive models. In this work, inspectional analysis and statistical modeling are used to create simple predictive models for a line drive design. Inspectional analysis on the partial differential equations governing this design yields a minimum number of fifteen dimensionless groups required to describe the physics of the system. These dimensionless groups are explained and confirmed using models with similar dimensionless groups but different dimensional parameters. This study models dimensionless production temperature and thermal recovery factor as the responses of a numerical model. These responses are obtained by a Box-Behnken experimental design. An uncertainty plot is used to segment the dimensionless time and develop a model for each segment. The important dimensionless numbers for each segment of the dimensionless time are identified using the Boosting method. These selected numbers are used in the regression models. The developed models are reduced to have a minimum number of predictors and interactions. The reduced final models are then presented and assessed using testing runs. Finally, applications of these models are offered. The presented workflow is generic and can be used to translate the output of a numerical simulator into simple predictive models in other research areas involving numerical simulation.

  4. A cognitive model for software architecture complexity

    NARCIS (Netherlands)

    Bouwers, E.; Lilienthal, C.; Visser, J.; Van Deursen, A.

    2010-01-01

    Evaluating the complexity of the architecture of a softwaresystem is a difficult task. Many aspects have to be considered to come to a balanced assessment. Several architecture evaluation methods have been proposed, but very few define a quality model to be used during the evaluation process. In add

  5. Effects of stratal architecture and diagenesis on reservoir development in the Grayburg formation: SSouth Cowden field, Ector County, Texas. Annual report, 1 October 1994--30 September 1995

    Energy Technology Data Exchange (ETDEWEB)

    Ruppel, S.; Bebout, D.

    1996-02-01

    This report presents the results of geological characterization studies in a typical Grayburg reservior in the Permian Basin. The work applies geological models developed in outcrop studies to better constrain the geological reservoir framework and heterogeneity in a typical Grayburg reservoir, The South Cowden Grayburg reservoir. This framework provides a strong basis for defining petrophysical and flow unit properties in the reservior and serves as a prototype model for other Grayburg reservoir characterization studies. The Grayburg Formation in the South Cowden field of eastern Ector County displays an internal stratal architecture that typifies Grayburg shallow-water platform successions throughout the Permian Basin. Study of core and wireline logs in South Cowden field documents three orders of cyclicity in the Grayburg. The entire Grayburg constitutes a single long-duration accommodation cycle that commenced with a major sea-level rise. Two major diagenetic events strongly affect reservoir character in some parts of the field. Recrystallized dolomite is developed along vertical burrows in highly cyclic mud-dominated packstones and wackestones of the HFS 4 Grayburg highstand succussion. Later alteration and removal of anhydrite are focused in structurally low sections along the eastern and southern margins of the field.

  6. Modeling of reservoir operation in UNH global hydrological model

    Science.gov (United States)

    Shiklomanov, Alexander; Prusevich, Alexander; Frolking, Steve; Glidden, Stanley; Lammers, Richard; Wisser, Dominik

    2015-04-01

    Climate is changing and river flow is an integrated characteristic reflecting numerous environmental processes and their changes aggregated over large areas. Anthropogenic impacts on the river flow, however, can significantly exceed the changes associated with climate variability. Besides of irrigation, reservoirs and dams are one of major anthropogenic factor affecting streamflow. They distort hydrological regime of many rivers by trapping of freshwater runoff, modifying timing of river discharge and increasing the evaporation rate. Thus, reservoirs is an integral part of the global hydrological system and their impacts on rivers have to be taken into account for better quantification and understanding of hydrological changes. We developed a new technique, which was incorporated into WBM-TrANS model (Water Balance Model-Transport from Anthropogenic and Natural Systems) to simulate river routing through large reservoirs and natural lakes based on information available from freely accessible databases such as GRanD (the Global Reservoir and Dam database) or NID (National Inventory of Dams for US). Different formulations were applied for unregulated spillway dams and lakes, and for 4 types of regulated reservoirs, which were subdivided based on main purpose including generic (multipurpose), hydropower generation, irrigation and water supply, and flood control. We also incorporated rules for reservoir fill up and draining at the times of construction and decommission based on available data. The model were tested for many reservoirs of different size and types located in various climatic conditions using several gridded meteorological data sets as model input and observed daily and monthly discharge data from GRDC (Global Runoff Data Center), USGS Water Data (US Geological Survey), and UNH archives. The best results with Nash-Sutcliffe model efficiency coefficient in the range of 0.5-0.9 were obtained for temperate zone of Northern Hemisphere where most of large

  7. Architectural view model for an integration platform

    Directory of Open Access Journals (Sweden)

    Tomasz Górski

    2012-03-01

    Full Text Available The most common architectural view model is "4+1" by Philipe Kruchten. This model presents the views required for a full description of computer system architecture. By contrast, this model seems to be insufficient to describe architecture of integration platform. Definitely lacks the view of integrated business processes. In the serviceoriented approach, one of the basic elements is a contract. It should also be included in the description of the architecture. Moreover, very important are integration mechanisms and mediation flows that should be presented in the description of architecture. Hence the need for integrated services view, and manner of their integration on the enterprise service bus. Use case view should also be extended by stereotypes required for presenting functionality exposed for other computer systems. It is therefore proposed architectural view model “1+5” for an integration platform. This model has following architectural views: Integrated processes, Use Cases, Logical, Integrated Services, Contracts, Deployment. Furthermore, in article was presented new UML profile "UML Profile for Integration Flows". In the profile were placed stereotypes corresponding to integration patterns and mediation mechanisms. It is important, that UML activity diagram was extended and its special form was obtained to model mediation flows on integration platform. Thus was proposed a new UML diagram: mediation flows diagram.

  8. MATHEMATICAL MODEL OF RIVER BED CHANGE DOWNSTREAM OF XIAOLANGDI RESERVOIR

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A mathematical model of river bed change downstream of the Xiaolangdi Reservoir was developed based on the most recent achievement of sediment theory in the Yellow River. The model was verified by the comparison of computed results and measured data from 1986 to 1996. Numerical prediction of the erosion and deposition downstream of the Xiaolangdi Reservoir in its first operation year was carried out, and a series of suggestions were given for reservoir operation mode in its early operation period.

  9. Integration of advanced geoscience and engineering techniques to quantify interwell heterogeneity in reservoir models. First annual report, September 29, 1993--September 30, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Martin, F.D.; Buckley, J.S.; Weiss, W.W.; Ouenes, A.

    1995-05-01

    The goal of this project is to provide a more quantitative definition of reservoir heterogeneity. This objective will be accomplished through the integration of geologic, geophysical, and engineering databases into a multidisciplinary understanding of reservoir architecture and associated fluid-rock and fluid-fluid interactions. The intent is to obtain a quantitative reservoir description incorporating outcrop, field, well-to-well, and laboratory core and fluid data of widely varying scales. This interdisciplinary effort will integrate geological and geophysical data with engineering and petrophysical results through reservoir simulation to quantify reservoir architecture and the dynamics of fluid-rock and fluid-fluid interactions. A more accurate reservoir description will allow greater accuracy and confidence during simulation and modeling as steps toward gaining greater recovery efficiency from existing reservoirs. A field laboratory, the Sulimar Queen Unit, is available for the field research activities that will be conducted.

  10. Integration of 3D photogrammetric outcrop models in the reservoir modelling workflow

    Science.gov (United States)

    Deschamps, Remy; Joseph, Philippe; Lerat, Olivier; Schmitz, Julien; Doligez, Brigitte; Jardin, Anne

    2014-05-01

    3D outcrop data, including geostatistical modelling and fluid flow simulations The case study is a turbidite reservoir analog in Northern Spain (Ainsa). In this case study, we can compare reservoir models that have been built with conventional data set (1D pseudowells), and reservoir model built from 3D outcrop data directly used to constrain the reservoir architecture. This approach allows us to assess the benefits of integrating geotagged 3D outcrop data into reservoir models. References: HODGETTS, D., (2013): Laser scanning and digital outcrop geology in the petroleum industry : a review. Marine and Petroleum Geology, 46, 335-354. McCAFFREY, K.J.W., JONES, R.R., HOLDSWORTH, R.E., WILSON, R.W., CLEGG, P., IMBER, J., HOLLIMAN, N., TRINKS, I., (2005): Unlocking the spatial dimension: digital technologies and the future of geoscience fieldwork. Journal of the Geological Society 162, 927-938 PRINGLE, J.K., HOWELL, J.A., HODGETTS, D., WESTERMAN, A.R., HODGSON, D.M., 2006. Virtual outcrop models of petroleum reservoir analogues: a review of the current state-of-the-art. First Break 24, 33-42.

  11. The Classification and Model of Coalbed Methane Reservoirs

    Institute of Scientific and Technical Information of China (English)

    SU Xianbo; LIN Xiaoying; SONG Yah; ZHAO Mengjun

    2004-01-01

    Coalbed methane has been explored in many basins worldwide for 30 years, and has been developed commercially in some of the basins. Many researchers have described the characteristics of coalbed methane geology and technology systematically. According to these investigations, a coalbed methane reservoir can be defined: "a coal seam that contains some coalbed methane and is isolated from other fluid units is called a coalbed methane reservoir".On the basis of anatomizafion, analysis, and comparison of the typical coalbed methane reservoirs, coalbed methane reservoirs can be divided into two classes: the hydrodynamic sealing coalbed methane reservoirs and the self-sealing coalbed methane reservoirs. The former can be further divided into two sub-classes: the hydrodynamic capping coalbed methane reservoirs, which can be divided into five types and the hydrodynamic driving coalbed methane reservoirs,which can be divided into three types. The latter can be divided into three types. Currently, hydrodynamic sealing reservoirs are the main target for coalbed methane exploration and development; self-sealing reservoirs are unsuitable for coalbed methane exploration and development, but they are closely related with coal mine gas hazards. Finally, a model for hydrodynamic sealing coalbed methane reservoirs is established.

  12. Daily reservoir sedimentation model: Case study from the Fena Valley Reservoir, Guam

    Science.gov (United States)

    Marineau, Mathieu D.; Wright, Scott A.

    2017-01-01

    A model to compute reservoir sedimentation rates at daily timescales is presented. The model uses streamflow and sediment load data from nearby stream gauges to obtain an initial estimate of sediment yield for the reservoir’s watershed; it is then calibrated to the total deposition calculated from repeat bathymetric surveys. Long-term changes to reservoir trapping efficiency are also taken into account. The model was applied to the Fena Valley Reservoir, a water supply reservoir on the island of Guam. This reservoir became operational in 1951 and was recently surveyed in 2014. The model results show that the highest rate of deposition occurred during two typhoons (Typhoon Alice in 1953 and Typhoon Tingting in 2004); each storm decreased reservoir capacity by approximately 2–3% in only a few days. The presented model can be used to evaluate the impact of an extreme event, or it can be coupled with a watershed runoff model to evaluate potential impacts to storage capacity as a result of climate change or other hydrologic modifications.

  13. Localisation and World Modelling: an Architectural Perspective

    Directory of Open Access Journals (Sweden)

    Domenico G. Sorrenti

    2008-11-01

    Full Text Available Autonomous robot world modelling is a "chicken-and-egg" problem: position estimation needs a model of the world, whereas world modelling needs the robot position. Most of the works dealing with this issue propose holistic solutions under an algorithmic perspective by neglecting software architecture issues. This results in huge and monolithic pieces of software where implementation details reify strategic decisions. An architectural approach founded on separation of concerns may help to break the loop. Localisation and modelling, acting on different time scales, are mostly independent of each other. Sometimes synchronisation is required. Whenever needed, an external strategy tunes the relative rates of the two activities. The paper introduces rationale, design, and implementation of such a system which relies on Real-Time Performers, a software architecture providing suitable architectural abstractions to observe and control the system's temporal behaviour.

  14. DEVELOPMENT OF RESERVOIR CHARACTERIZATION TECHNIQUES AND PRODUCTION MODELS FOR EXPLOITING NATURALLY FRACTURED RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Michael L. Wiggins; Raymon L. Brown; Faruk Civan; Richard G. Hughes

    2002-12-31

    For many years, geoscientists and engineers have undertaken research to characterize naturally fractured reservoirs. Geoscientists have focused on understanding the process of fracturing and the subsequent measurement and description of fracture characteristics. Engineers have concentrated on the fluid flow behavior in the fracture-porous media system and the development of models to predict the hydrocarbon production from these complex systems. This research attempts to integrate these two complementary views to develop a quantitative reservoir characterization methodology and flow performance model for naturally fractured reservoirs. The research has focused on estimating naturally fractured reservoir properties from seismic data, predicting fracture characteristics from well logs, and developing a naturally fractured reservoir simulator. It is important to develop techniques that can be applied to estimate the important parameters in predicting the performance of naturally fractured reservoirs. This project proposes a method to relate seismic properties to the elastic compliance and permeability of the reservoir based upon a sugar cube model. In addition, methods are presented to use conventional well logs to estimate localized fracture information for reservoir characterization purposes. The ability to estimate fracture information from conventional well logs is very important in older wells where data are often limited. Finally, a desktop naturally fractured reservoir simulator has been developed for the purpose of predicting the performance of these complex reservoirs. The simulator incorporates vertical and horizontal wellbore models, methods to handle matrix to fracture fluid transfer, and fracture permeability tensors. This research project has developed methods to characterize and study the performance of naturally fractured reservoirs that integrate geoscience and engineering data. This is an important step in developing exploitation strategies for

  15. Enterprise architecture at work modelling, communication and analysis

    CERN Document Server

    Lankhorst, Marc

    2017-01-01

    This book offers a coherent modeling language that captures the complexity of architectural domains and their relations, allowing the construction of integrated enterprise architecture models. Introduces the ArchiMate® language for enterprise architecture.

  16. The Ragnarok Architectural Software Configuration Management Model

    DEFF Research Database (Denmark)

    Christensen, Henrik Bærbak

    1999-01-01

    . This introduces an unfortunate impedance mismatch between the design domain (architecture level) and configuration management domain (file level.) This paper presents a software configuration management model that allows tight version control and configuration management of the architecture of a software system......The architecture is the fundamental framework for designing and implementing large scale software, and the ability to trace and control its evolution is essential. However, many traditional software configuration management tools view 'software' merely as a set of files, not as an architecture....... Essential features of the model have been implemented in a research prototype, Ragnarok. Two years of experience using Ragnarok in three, real, small- to medium sized, projects is reported. The conclusion is that the presented model is viable, feels 'natural' for developers, and provides good support...

  17. Modeling and analyzing architectural change with alloy

    DEFF Research Database (Denmark)

    Hansen, Klaus Marius; Ingstrup, Mads

    2010-01-01

    to the uptake of reconfiguration techniques in industry. Using the Alloy language and associated tool, we propose a practical way to formally model and analyze runtime architectural change expressed as architectural scripts. Our evaluation shows the performance to be acceptable; our experience......Although adaptivity based on reconfiguration has the potential to improve dependability of systems, the cost of a failed attempt at reconfiguration is prohibitive in precisely the applications where high dependability is required. Existing work on formal modeling and verification of architectural...... reconfigurations partly achieve the goal of ensuring correctness, however the formalisms used often lack tool support and the ensuing models have uncertain relation to a concrete implementation. Thus a practical way to ensure with formal certainty that specific architectural changes are correct remains a barrier...

  18. Geostatistical modeling of a fluviodeltaic reservoir in the Huyapari Field, Hamaca area, in the Faja Petrolifera del Orinoco, Venezuela

    Energy Technology Data Exchange (ETDEWEB)

    De Ascencao, Erika M.; Munckton, Toni; Digregorio, Ricardo [Petropiar (Venezuela)

    2011-07-01

    The Huyapari field, situated within the Faja Petrolifera del Orinoco (FPO) of Venezuela presents unique problems in terms of modeling. This field is spread over a wide area and is therefore subject to variable oil quality and complex fluvial facies architecture. Ameriven and PDVSA have been working on characterizing the ld's reservoirs in this field since 2000 and the aim of this paper is to present these efforts. Among others, a 3-D seismic survey completed in 1998 and a stratigraphic framework built from 149 vertical wells were used for reservoir characterization. Geostatistical techniques such as sequential Gaussian simulation with locally varying mean and cloud transform were also used. Results showed that these geostatistical methods accurately represented the architecture and properties of the reservoir and its fluid distribution. This paper showed that the application of numerous different techniques in the Hamasca area permitted reservoir complexity to be captured.

  19. Software Architecture Viewpoint Models: A Short Survey

    Directory of Open Access Journals (Sweden)

    Seyyed Ali Razavi Ebrahimi

    2013-11-01

    Full Text Available A software architecture is a complex entity that cannot be described in a simple one-dimensional fashion. The architecture views used to describe software provide the architect with a means of explaining the architecture to stakeholders. Each view presents different aspects of the system that fulfill functional and non-functional requirements. A view of a system is a representation of the system from the perspective of a viewpoint. Architecture viewpoints in software products provide guidelines to describe uniformly the total system and its subsystems. It defines the stakeholders whose concerns are reflected in the viewpoint and the guidelines, principles, and template models for constructing its views. The results of this study may serve as a roadmap to the software developers and architects in helping them select the appropriate viewpoint model based on the stakeholders and concerns that need to be covered by views.

  20. Electromagnetic Physics Models for Parallel Computing Architectures

    Science.gov (United States)

    Amadio, G.; Ananya, A.; Apostolakis, J.; Aurora, A.; Bandieramonte, M.; Bhattacharyya, A.; Bianchini, C.; Brun, R.; Canal, P.; Carminati, F.; Duhem, L.; Elvira, D.; Gheata, A.; Gheata, M.; Goulas, I.; Iope, R.; Jun, S. Y.; Lima, G.; Mohanty, A.; Nikitina, T.; Novak, M.; Pokorski, W.; Ribon, A.; Seghal, R.; Shadura, O.; Vallecorsa, S.; Wenzel, S.; Zhang, Y.

    2016-10-01

    The recent emergence of hardware architectures characterized by many-core or accelerated processors has opened new opportunities for concurrent programming models taking advantage of both SIMD and SIMT architectures. GeantV, a next generation detector simulation, has been designed to exploit both the vector capability of mainstream CPUs and multi-threading capabilities of coprocessors including NVidia GPUs and Intel Xeon Phi. The characteristics of these architectures are very different in terms of the vectorization depth and type of parallelization needed to achieve optimal performance. In this paper we describe implementation of electromagnetic physics models developed for parallel computing architectures as a part of the GeantV project. Results of preliminary performance evaluation and physics validation are presented as well.

  1. The Architectural Information Map: Semantic modeling in conceptual architectural design

    NARCIS (Netherlands)

    Tunçer, E.B.

    2009-01-01

    This research focuses on the acquisition, representation, sharing and reuse of design information and knowledge in the conceptual phase of architectural design, and targets the creation of situated digital environments where communities of architectural practice communicate and collaborate using thi

  2. The Architectural Information Map: Semantic modeling in conceptual architectural design

    NARCIS (Netherlands)

    Tunçer, E.B.

    2009-01-01

    This research focuses on the acquisition, representation, sharing and reuse of design information and knowledge in the conceptual phase of architectural design, and targets the creation of situated digital environments where communities of architectural practice communicate and collaborate using

  3. Modeling reservoir geomechanics using discrete element method : Application to reservoir monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Alassi, Haitham Tayseer

    2008-09-15

    Understanding reservoir geomechanical behavior is becoming more and more important for the petroleum industry. Reservoir compaction, which may result in surface subsidence and fault reactivation, occurs during reservoir depletion. Stress changes and possible fracture development inside and outside a depleting reservoir can be monitored using time-lapse (so-called '4D') seismic and/or passive seismic, and this can give valuable information about the conditions of a given reservoir during production. In this study we will focus on using the (particle-based) Discrete Element Method (DEM) to model reservoir geomechanical behavior during depletion and fluid injection. We show in this study that DEM can be used in modeling reservoir geomechanical behavior by comparing results obtained from DEM to those obtained from analytical solutions. The match of the displacement field between DEM and the analytical solution is good, however there is mismatch of the stress field which is related to the way stress is measured in DEM. A good match is however obtained by measuring the stress field carefully. We also use DEM to model reservoir geomechanical behavior beyond the elasticity limit where fractures can develop and faults can reactivate. A general technique has been developed to relate DEM parameters to rock properties. This is necessary in order to use correct reservoir geomechanical properties during modeling. For any type of particle packing there is a limitation that the maximum ratio between P- and S-wave velocity Vp/Vs that can be modeled is 3 . The static behavior for a loose packing is different from the dynamic behavior. Empirical relations are needed for the static behavior based on numerical test observations. The dynamic behavior for both dense and loose packing can be given by analytical relations. Cosserat continuum theory is needed to derive relations for Vp and Vs. It is shown that by constraining the particle rotation, the S-wave velocity can be

  4. Modelling of Reservoir Operations using Fuzzy Logic and ANNs

    Science.gov (United States)

    Van De Giesen, N.; Coerver, B.; Rutten, M.

    2015-12-01

    Today, almost 40.000 large reservoirs, containing approximately 6.000 km3 of water and inundating an area of almost 400.000 km2, can be found on earth. Since these reservoirs have a storage capacity of almost one-sixth of the global annual river discharge they have a large impact on the timing, volume and peaks of river discharges. Global Hydrological Models (GHM) are thus significantly influenced by these anthropogenic changes in river flows. We developed a parametrically parsimonious method to extract operational rules based on historical reservoir storage and inflow time-series. Managing a reservoir is an imprecise and vague undertaking. Operators always face uncertainties about inflows, evaporation, seepage losses and various water demands to be met. They often base their decisions on experience and on available information, like reservoir storage and the previous periods inflow. We modeled this decision-making process through a combination of fuzzy logic and artificial neural networks in an Adaptive-Network-based Fuzzy Inference System (ANFIS). In a sensitivity analysis, we compared results for reservoirs in Vietnam, Central Asia and the USA. ANFIS can indeed capture reservoirs operations adequately when fed with a historical monthly time-series of inflows and storage. It was shown that using ANFIS, operational rules of existing reservoirs can be derived without much prior knowledge about the reservoirs. Their validity was tested by comparing actual and simulated releases with each other. For the eleven reservoirs modelled, the normalised outflow, , was predicted with a MSE of 0.002 to 0.044. The rules can be incorporated into GHMs. After a network for a specific reservoir has been trained, the inflow calculated by the hydrological model can be combined with the release and initial storage to calculate the storage for the next time-step using a mass balance. Subsequently, the release can be predicted one time-step ahead using the inflow and storage.

  5. The egg model - A geological ensemble for reservoir simulation

    NARCIS (Netherlands)

    Jansen, J.D.; Fonseca, R.M.; Kahrobaei, S.; Siraj, M.M.; Van Essen, G.M.; Van den Hof, P.M.J.

    2014-01-01

    The ‘Egg Model’ is a synthetic reservoir model consisting of an ensemble of 101 relatively small three-dimensional realizations of a channelized oil reservoir produced under water flooding conditions with eight water injectors and four oil producers. It has been used in numerous publications to

  6. The egg model - A geological ensemble for reservoir simulation

    NARCIS (Netherlands)

    Jansen, J.D.; Fonseca, R.M.; Kahrobaei, S.; Siraj, M.M.; Van Essen, G.M.; Van den Hof, P.M.J.

    2014-01-01

    The ‘Egg Model’ is a synthetic reservoir model consisting of an ensemble of 101 relatively small three-dimensional realizations of a channelized oil reservoir produced under water flooding conditions with eight water injectors and four oil producers. It has been used in numerous publications to demo

  7. Architecture Descriptions. A Contribution to Modeling of Production System Architecture

    DEFF Research Database (Denmark)

    Jepsen, Allan Dam; Hvam, Lars

    The subject of this PhD dissertation is architecture-centric design and the description of production system architecture. Companies are facing demands for the development and production of new products at an ever increasing rate, as the market life of products decreases and the rate at which...... design. This research contributes to the vocabulary and understanding of the architecture phenomenon. A conceptual framework is provided which allows for conceptualization of the architecture phenomenon, and how it applies within production system design. To aid the companies in the operational design...... and handling of production system architecture, research is conducted into the description of production system architecture, including what an architecture description contains in general and what it should describe for production systems specifically. The contribution in this area of research consists...

  8. Model Driven Architecture: Foundations and Applications

    NARCIS (Netherlands)

    Rensink, Arend

    The OMG's Model Driven Architecture (MDA) initiative has been the focus of much attention in both academia and industry, due to its promise of more rapid and consistent software development through the increased use of models. In order for MDA to reach its full potential, the ability to manipulate

  9. Integrated reservoir and decision modeling to optimize spacing in unconventional gas reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Turkarslan, G.; McVay, D.A.; Ortiz, R.R. [Texas A and M Univ., College Station, TX (United States); Bickel, J.E.; Montiel, L.V. [Texas Univ., Austin, TX (United States)

    2010-07-01

    Unconventional gas plays are risky and operators must balance the need to conserve capital and protect the environment by avoiding over drilling with the desire to increase profitability. The purpose of this study was to develop technology and tools to help operators determine optimal well spacing in highly uncertain and risky unconventional gas reservoirs as quickly as possible. The paper presented a study that developed an integrated reservoir and decision modeling system that incorporated uncertainty. A Monte Carlo simulation was used to match and predict production performance in unconventional gas reservoirs. Simulation results were integrated with a Bayesian decision model that accounted for the risk facing operators. In order to determine optimal development strategies, these integrated tools were applied to a hypothetical case based on data from Deep Basin tight gas sands in Alberta. The paper provided background information on the Deep Basin Sands and the reservoir model. The Monte Carlo simulation and geostatistical analysis were presented. It was concluded that it is important to incorporate the lessons learned between development stages in unconventional gas reservoirs. 23 refs., 9 tabs., 16 figs.

  10. Runoff Simulation of Shitoukoumen Reservoir Basin Based on SWAT Model

    Institute of Scientific and Technical Information of China (English)

    XIE; Miao; LI; Hong-yan; LIU; Tie-juan; RU; Shi-rong

    2012-01-01

    [Objective]The study aimed to simulate the runoff of Shitoukoumen Reservoir basin by using SWAT model. [Method] Based on DEM elevation, land use type, soil type and hydrometeorological data, SWAT model, a distributed hydrological model was established to simulate the monthly runoff of Shitoukoumen Reservoir basin, and the years 2006 and 2010 were chosen as the calibration and validation period respectively. [Result] The simulation results indicated that SWAT model could be used to simulate the runoff of Shitoukoumen Reservoir basin, and the simulation effect was good. However, the response of the model to local rainstorm was not obvious, so that the actual runoff in June and July of 2010 was abnormally higher than the simulation value. [Conclusion] The research could provide theoretical references for the plan and management of water resources in Shitoukoumen Reservoir basin in future.

  11. Advancing reservoir operation description in physically based hydrological models

    Science.gov (United States)

    Anghileri, Daniela; Giudici, Federico; Castelletti, Andrea; Burlando, Paolo

    2016-04-01

    Last decades have seen significant advances in our capacity of characterizing and reproducing hydrological processes within physically based models. Yet, when the human component is considered (e.g. reservoirs, water distribution systems), the associated decisions are generally modeled with very simplistic rules, which might underperform in reproducing the actual operators' behaviour on a daily or sub-daily basis. For example, reservoir operations are usually described by a target-level rule curve, which represents the level that the reservoir should track during normal operating conditions. The associated release decision is determined by the current state of the reservoir relative to the rule curve. This modeling approach can reasonably reproduce the seasonal water volume shift due to reservoir operation. Still, it cannot capture more complex decision making processes in response, e.g., to the fluctuations of energy prices and demands, the temporal unavailability of power plants or varying amount of snow accumulated in the basin. In this work, we link a physically explicit hydrological model with detailed hydropower behavioural models describing the decision making process by the dam operator. In particular, we consider two categories of behavioural models: explicit or rule-based behavioural models, where reservoir operating rules are empirically inferred from observational data, and implicit or optimization based behavioural models, where, following a normative economic approach, the decision maker is represented as a rational agent maximising a utility function. We compare these two alternate modelling approaches on the real-world water system of Lake Como catchment in the Italian Alps. The water system is characterized by the presence of 18 artificial hydropower reservoirs generating almost 13% of the Italian hydropower production. Results show to which extent the hydrological regime in the catchment is affected by different behavioural models and reservoir

  12. Issues in geothermal reservoir engineering, modeling, and numerical simulation

    Energy Technology Data Exchange (ETDEWEB)

    Pritchett, J.W. (S-Cubed, La Jolla, CA (United States))

    1996-01-01

    The theoretical basis of geothermal reservoir engineering owes much of its origins to the oil and gas industries, but important differences in resource character and geological setting have resulted in substantial divergences from reservoir simulation as practiced in the petroleum industry. Geothermal reservoirs are hotter, contain different fluids, and are usually found within fractured volcanic formations with little or no intergranular permeability. Fluid flow takes place through an intricate fracture network which penetrates the otherwise impermeable rock. By their very nature, oil and gas fields prior to production are usually static (little or no natural fluid circulation) whereas, by contrast, the presence of a dynamic active natural convective circulation system is an essential prerequisite to the formation of a geo-thermal reservoir-otherwise, the earth's heat cannot penetrate upward to drillable depths. Geothermal reservoirs usually lack the regular sub-horizontal stratification pattern typical of oilfields. The resource sought (heat) is mainly contained within the mass of the rock, so that the geothermal brines serve as working fluids to redistribute this heat within the reservoir and carry it upward. During exploitation, flow rates are necessarily high (the economic value per unit mass of hot brine is vastly less than that of oil), and the objective is to create an artificial circulation system using production and injection wells to mine energy from the reservoir by cooling the rock. These phenomenological differences have resulted in development of new techniques of reservoir modeling and simulation for geothermal applications.

  13. Issues in geothermal reservoir engineering, modeling, and numerical simulation

    Energy Technology Data Exchange (ETDEWEB)

    Pritchett, J.W. [S-Cubed, La Jolla, CA (United States)

    1996-12-31

    The theoretical basis of geothermal reservoir engineering owes much of its origins to the oil and gas industries, but important differences in resource character and geological setting have resulted in substantial divergences from reservoir simulation as practiced in the petroleum industry. Geothermal reservoirs are hotter, contain different fluids, and are usually found within fractured volcanic formations with little or no intergranular permeability. Fluid flow takes place through an intricate fracture network which penetrates the otherwise impermeable rock. By their very nature, oil and gas fields prior to production are usually static (little or no natural fluid circulation) whereas, by contrast, the presence of a dynamic active natural convective circulation system is an essential prerequisite to the formation of a geo-thermal reservoir-otherwise, the earth`s heat cannot penetrate upward to drillable depths. Geothermal reservoirs usually lack the regular sub-horizontal stratification pattern typical of oilfields. The resource sought (heat) is mainly contained within the mass of the rock, so that the geothermal brines serve as working fluids to redistribute this heat within the reservoir and carry it upward. During exploitation, flow rates are necessarily high (the economic value per unit mass of hot brine is vastly less than that of oil), and the objective is to create an artificial circulation system using production and injection wells to mine energy from the reservoir by cooling the rock. These phenomenological differences have resulted in development of new techniques of reservoir modeling and simulation for geothermal applications.

  14. Three dimensional heat transport modeling in Vossoroca reservoir

    Science.gov (United States)

    Arcie Polli, Bruna; Yoshioka Bernardo, Julio Werner; Hilgert, Stephan; Bleninger, Tobias

    2017-04-01

    Freshwater reservoirs are used for many purposes as hydropower generation, water supply and irrigation. In Brazil, according to the National Energy Balance of 2013, hydropower energy corresponds to 70.1% of the Brazilian demand. Superficial waters (which include rivers, lakes and reservoirs) are the most used source for drinking water supply - 56% of the municipalities use superficial waters as a source of water. The last two years have shown that the Brazilian water and electricity supply is highly vulnerable and that improved management is urgently needed. The construction of reservoirs affects physical, chemical and biological characteristics of the water body, e.g. stratification, temperature, residence time and turbulence reduction. Some water quality issues related to reservoirs are eutrophication, greenhouse gas emission to the atmosphere and dissolved oxygen depletion in the hypolimnion. The understanding of the physical processes in the water body is fundamental to reservoir management. Lakes and reservoirs may present a seasonal behavior and stratify due to hydrological and meteorological conditions, and especially its vertical distribution may be related to water quality. Stratification can control heat and dissolved substances transport. It has been also reported the importance of horizontal temperature gradients, e.g. inflows and its density and processes of mass transfer from shallow to deeper regions of the reservoir, that also may impact water quality. Three dimensional modeling of the heat transport in lakes and reservoirs is an important tool to the understanding and management of these systems. It is possible to estimate periods of large vertical temperature gradients, inhibiting vertical transport and horizontal gradients, which could be responsible for horizontal transport of heat and substances (e.g. differential cooling or inflows). Vossoroca reservoir was constructed in 1949 by the impoundment of São João River and is located near to

  15. Borehole radar modeling for reservoir monitoring applications

    NARCIS (Netherlands)

    Miorali, M.; Slob, E.C.; Arts, R.J.

    2010-01-01

    The use of down-hole sensors and remotely controlled valves in wells provide enormous benefits to reservoir management and oil production. We suggest borehole radar measurements as a promising technique capable of monitoring the arrival of undesired fluids in the proximity of production wells. The h

  16. Borehole radar modeling for reservoir monitoring applications

    NARCIS (Netherlands)

    Miorali, M.; Slob, E.C.; Arts, R.J.

    2010-01-01

    The use of down-hole sensors and remotely controlled valves in wells provide enormous benefits to reservoir management and oil production. We suggest borehole radar measurements as a promising technique capable of monitoring the arrival of undesired fluids in the proximity of production wells. The

  17. Paleotopography association, lithofacies architecture, and reservoir quality of the upper James Lime reservoir (Pearsall Fm, Lower Cretaceous) in the Poplarville field, Pearl River County, Mississippi

    Energy Technology Data Exchange (ETDEWEB)

    Loucks, R. [Arco Exploration and Production Technology, Plano, TX (United States); Abel, C.; Ver Hoeve, M. [Vastar Resources Inc., Houston, TX (United States)

    1996-09-01

    The James Lime has been an exploration target since the discovery of the Fairway Field in the East Texas Basin in 1960. This study focuses on a deep James Lime gas discovery (14,000 to 14,500 ft) in the Mississippi Salt Basin made by Exxon in the early 1980s. The relationships among paleotopography, lithofacies architecture, and reservoir quality in the Poplarville field provide guidance for exploring for other James Lime prospects. Distribution of the James Lime reservoir facies is controlled by paleotopography associated with deeper buried salt structures. Nine lithofacies are recognized from core and are correlable with wireline log responses. They range from deeper water, low-energy wackestones, packstones, and hydrozoa/cryptalgal bindstones deposited during sea-level transgression to shallower water, high-energy Requinid/coral packstones, grainstones, and boundstones deposited during sea-level highstand. These lithofacies are laterally restricted. Reservoir quality is controlled by depositional facies and diagenesis. Nearly all porosity occurs in the Requinid/coral packstones, grainstones, and boundstones. The packstones and boundstones mainly contain ineffective moldic and micro-porosity. Porosity ranges from 5 to 16% and permeability ranges form <0.01 to 7 md. In contrast, the pore network in the grainstones consists of effective interparticle and some moldic porosity. Permeability is estimated to range between 1 to 10 md. Exploration should be focused toward areas where paleotopography produced shoaling condition during James Lime deposition. The Requinid/coral grainstones will be the main pay, however, at depths in the range 14,000 ft, only fair reservoir quality should be expected.

  18. Optimization and mathematical modeling in computer architecture

    CERN Document Server

    Sankaralingam, Karu; Nowatzki, Tony

    2013-01-01

    In this book we give an overview of modeling techniques used to describe computer systems to mathematical optimization tools. We give a brief introduction to various classes of mathematical optimization frameworks with special focus on mixed integer linear programming which provides a good balance between solver time and expressiveness. We present four detailed case studies -- instruction set customization, data center resource management, spatial architecture scheduling, and resource allocation in tiled architectures -- showing how MILP can be used and quantifying by how much it outperforms t

  19. Generalized effective medium resistivity model for low resistivity reservoir

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    With the advancement in oil exploration,producible oil and gas are being found in low resistivity reservoirs,which may otherwise be erroneously thought as water zones from their resistivity.However,the evaluation of low resistivity reservoirs remains difficult from log interpretation.Since low resistivity in hydrocarbon bearing sands can be caused by dispersed clay,laminated shale,conductive matrix grains,microscopic capillary pores and high saline water,a new resistivity model is required for more accurate hydrocarbon saturation prediction for low resistivity formations.Herein,a generalized effective medium resistivity model has been proposed for low resistivity reservoirs,based on experimental measurements on artificial low resistivity shaly sand samples,symmetrical anisotropic effective medium theory for resistivity interpretations,and geneses and conductance mechanisms of low resistivity reservoirs.By analyzing effects of some factors on the proposed model,we show theoretically the model can describe conductance mechanisms of low resistivity reservoirs with five geneses.Also,shale distribution largely affects water saturation predicted by the model.Resistivity index decreases as fraction and conductivity of laminated shale,or fraction of dispersed clay,or conductivity of rock matrix grains increases.Resistivity index decreases as matrix percolation exponent,or percolation rate of capillary bound water increases,and as percolation exponent of capillary bound water,or matrix percolation rate,or free water percolation rate decreases.Rock sample data from low resistivity reservoirs with different geneses and interpretation results for log data show that the proposed model can be applied in low resistivity reservoirs containing high salinity water,dispersed clay,microscopic capillary pores,laminated shale and conductive matrix grains,and thus is considered as a generalized resistivity model for low resistivity reservoir evaluation.

  20. Generalized effective medium resistivity model for low resistivity reservoir

    Institute of Scientific and Technical Information of China (English)

    SONG YanJie; TANG XiaoMin

    2008-01-01

    With the advancement in oil exploration, producible oil and gas are being found in low resistivity reservoirs, which may otherwise be erroneously thought as water zones from their resistivity. However,the evaluation of low resistivity reservoirs remains difficult from log interpretation. Since low resistivity in hydrocarbon bearing sands can be caused by dispersed clay, laminated shale, conductive matrix grains, microscopic capillary pores and high saline water, a new resistivity model is required for more accurate hydrocarbon saturation prediction for low resistivity formations. Herein, a generalized effective medium resistivity model has been proposed for low resistivity reservoirs, based on experimental measurements on artificial low resistivity shaly sand samples, symmetrical anisotropic effective medium theory for resistivity interpretations, and geneses and conductance mechanisms of low resistivity reservoirs. By analyzing effects of some factors on the proposed model, we show theoretically the model can describe conductance mechanisms of low resistivity reservoirs with five geneses. Also,shale distribution largely affects water saturation predicted by the model. Resistivity index decreases as fraction and conductivity of laminated shale, or fraction of dispersed clay, or conductivity of rock matrix grains increases. Resistivity index decreases as matrix percolation exponent, or percolation rate of capillary bound water increases, and as percolation exponent of capillary bound water, or matrix percolation rate, or free water percolation rate decreases. Rock sample data from low resistivity reservoirs with different geneses and interpretation results for log data show that the proposed model can be applied in low resistivity reservoirs containing high salinity water, dispersed clay, microscopic capillary pores, laminated shale and conductive matrix grains, and thus is considered as a generalized resistivity model for low resistivity reservoir evaluation.

  1. Process Models for Security Architectures

    Directory of Open Access Journals (Sweden)

    Floarea NASTASE

    2006-01-01

    Full Text Available This paper presents a model for an integrated security system, which can be implemented in any organization. It is based on security-specific standards and taxonomies as ISO 7498-2 and Common Criteria. The functionalities are derived from the classes proposed in the Common Criteria document. In the paper we present the process model for each functionality and also we focus on the specific components.

  2. A Dualistic Model To Describe Computer Architectures

    Science.gov (United States)

    Nitezki, Peter; Engel, Michael

    1985-07-01

    The Dualistic Model for Computer Architecture Description uses a hierarchy of abstraction levels to describe a computer in arbitrary steps of refinement from the top of the user interface to the bottom of the gate level. In our Dualistic Model the description of an architecture may be divided into two major parts called "Concept" and "Realization". The Concept of an architecture on each level of the hierarchy is an Abstract Data Type that describes the functionality of the computer and an implementation of that data type relative to the data type of the next lower level of abstraction. The Realization on each level comprises a language describing the means of user interaction with the machine, and a processor interpreting this language in terms of the language of the lower level. The surface of each hierarchical level, the data type and the language express the behaviour of a ma-chine at this level, whereas the implementation and the processor describe the structure of the algorithms and the system. In this model the Principle of Operation maps the object and computational structure of the Concept onto the structures of the Realization. Describing a system in terms of the Dualistic Model is therefore a process of refinement starting at a mere description of behaviour and ending at a description of structure. This model has proven to be a very valuable tool in exploiting the parallelism in a problem and it is very transparent in discovering the points where par-allelism is lost in a special architecture. It has successfully been used in a project on a survey of Computer Architecture for Image Processing and Pattern Analysis in Germany.

  3. Sampling from stochastic reservoir models constrained by production data

    Energy Technology Data Exchange (ETDEWEB)

    Hegstad, Bjoern Kaare

    1997-12-31

    When a petroleum reservoir is evaluated, it is important to forecast future production of oil and gas and to assess forecast uncertainty. This is done by defining a stochastic model for the reservoir characteristics, generating realizations from this model and applying a fluid flow simulator to the realizations. The reservoir characteristics define the geometry of the reservoir, initial saturation, petrophysical properties etc. This thesis discusses how to generate realizations constrained by production data, that is to say, the realizations should reproduce the observed production history of the petroleum reservoir within the uncertainty of these data. The topics discussed are: (1) Theoretical framework, (2) History matching, forecasting and forecasting uncertainty, (3) A three-dimensional test case, (4) Modelling transmissibility multipliers by Markov random fields, (5) Up scaling, (6) The link between model parameters, well observations and production history in a simple test case, (7) Sampling the posterior using optimization in a hierarchical model, (8) A comparison of Rejection Sampling and Metropolis-Hastings algorithm, (9) Stochastic simulation and conditioning by annealing in reservoir description, and (10) Uncertainty assessment in history matching and forecasting. 139 refs., 85 figs., 1 tab.

  4. Integration of production data into reservoir models

    Energy Technology Data Exchange (ETDEWEB)

    Oliver, D.S.; Reynolds, A.C.; Abacioglu, Y. [Tulsa Univ., Dept. of Petroleum Engineering, Tulsa, OK (United States); Bi, Z. [Duke Univ., Mathematics Dept., Durham, NC (United States)

    2001-05-01

    The problem of mapping reservoir properties, such as porosity and permeability, and of assessing the uncertainty in the mapping has been largely approached probabilistically, i.e. uncertainty is estimated based on the properties of an ensemble of random realizations of the reservoir properties all of which satisfy constraints provided by data and prior geological knowledge. When the constraints include observations of production characteristics, the problem of generating a representative ensemble of realizations can be quite difficult partly because the connection between a measurement of water-cut or GOR at a well and the permeability at some other location is by no means obvious. In this paper, the progress towards incorporation of production data and remaining challenges are reviewed. (Author)

  5. Study on detailed geological modelling for fluvial sandstone reservoir in Daqing oil field

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Hanqing; Fu Zhiguo; Lu Xiaoguang [Institute of Petroleum Exploration and Development, Daqing (China)

    1997-08-01

    Guided by the sedimentation theory and knowledge of modern and ancient fluvial deposition and utilizing the abundant information of sedimentary series, microfacies type and petrophysical parameters from well logging curves of close spaced thousands of wells located in a large area. A new method for establishing detailed sedimentation and permeability distribution models for fluvial reservoirs have been developed successfully. This study aimed at the geometry and internal architecture of sandbodies, in accordance to their hierarchical levels of heterogeneity and building up sedimentation and permeability distribution models of fluvial reservoirs, describing the reservoir heterogeneity on the light of the river sedimentary rules. The results and methods obtained in outcrop and modem sedimentation studies have successfully supported the study. Taking advantage of this method, the major producing layers (PI{sub 1-2}), which have been considered as heterogeneous and thick fluvial reservoirs extending widely in lateral are researched in detail. These layers are subdivided into single sedimentary units vertically and the microfacies are identified horizontally. Furthermore, a complex system is recognized according to their hierarchical levels from large to small, meander belt, single channel sandbody, meander scroll, point bar, and lateral accretion bodies of point bar. The achieved results improved the description of areal distribution of point bar sandbodies, provide an accurate and detailed framework model for establishing high resolution predicting model. By using geostatistic technique, it also plays an important role in searching for enriched zone of residual oil distribution.

  6. Plastic Super Models: aesthetics, architecture and the model of emergence

    Directory of Open Access Journals (Sweden)

    Pia Ednie-Brown

    2008-01-01

    Full Text Available Modelling is at the core of what architects do, rendering the discipline especially fragile and sensitive to shifts in the nature of models and modelling. A digitally-based, explorative architectural milieu has been actively modelling in tune with a socio-cultural paradigm related to the concept of emergence, presenting numerous challenges to a range of assumptions about the activity of architectural design. This paper explores how this milieu has acted to unsettle the cool containments of architectural composure by bringing affective activity emphatically to the foreground.

  7. An Evaluation of ADLs on Modeling Patterns for Software Architecture

    NARCIS (Netherlands)

    Waqas Kamal, Ahmad; Avgeriou, Paris

    2007-01-01

    Architecture patterns provide solutions to recurring design problems at the architecture level. In order to model patterns during software architecture design, one may use a number of existing Architecture Description Languages (ADLs), including the UML, a generic language but also a de facto

  8. Integration of dynamical data in a geostatistical model of reservoir; Integration des donnees dynamiques dans un modele geostatistique de reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Costa Reis, L.

    2001-01-01

    We have developed in this thesis a methodology of integrated characterization of heterogeneous reservoirs, from geologic modeling to history matching. This methodology is applied to the reservoir PBR, situated in Campos Basin, offshore Brazil, which has been producing since June 1979. This work is an extension of two other thesis concerning geologic and geostatistical modeling of the reservoir PBR from well data and seismic information. We extended the geostatistical litho-type model to the whole reservoir by using a particular approach of the non-stationary truncated Gaussian simulation method. This approach facilitated the application of the gradual deformation method to history matching. The main stages of the methodology for dynamic data integration in a geostatistical reservoir model are presented. We constructed a reservoir model and the initial difficulties in the history matching led us to modify some choices in the geological, geostatistical and flow models. These difficulties show the importance of dynamic data integration in reservoir modeling. The petrophysical property assignment within the litho-types was done by using well test data. We used an inversion procedure to evaluate the petrophysical parameters of the litho-types. The up-scaling is a necessary stage to reduce the flow simulation time. We compared several up-scaling methods and we show that the passage from the fine geostatistical model to the coarse flow model should be done very carefully. The choice of the fitting parameter depends on the objective of the study. In the case of the reservoir PBR, where water is injected in order to improve the oil recovery, the water rate of the producing wells is directly related to the reservoir heterogeneity. Thus, the water rate was chosen as the fitting parameter. We obtained significant improvements in the history matching of the reservoir PBR. First, by using a method we have proposed, called patchwork. This method allows us to built a coherent

  9. A goal-oriented requirements modelling language for enterprise architecture

    NARCIS (Netherlands)

    Quartel, Dick; Engelsman, Wilco; Jonkers, Henk; Sinderen, van Marten

    2009-01-01

    Methods for enterprise architecture, such as TOGAF, acknowledge the importance of requirements engineering in the development of enterprise architectures. Modelling support is needed to specify, document, communicate and reason about goals and requirements. Current modelling techniques for enterpris

  10. A goal-oriented requirements modelling language for enterprise architecture

    NARCIS (Netherlands)

    Quartel, Dick; Engelsman, W.; Jonkers, Henk; van Sinderen, Marten J.

    2009-01-01

    Methods for enterprise architecture, such as TOGAF, acknowledge the importance of requirements engineering in the development of enterprise architectures. Modelling support is needed to specify, document, communicate and reason about goals and requirements. Current modelling techniques for

  11. Three-dimensional modelling of stacked turbidite channels in West Africa: impact on dynamic reservoir simulations

    Energy Technology Data Exchange (ETDEWEB)

    Labourdette, Richard; Poncet, Jerome; Seguin, Julien; Temple, Francois [Total, Geoscience Technologies, Pau, 64 (France); Hegre, JoAnn; Irving, Alan [Total E and P UK plc, Geoscience Research Centre, Aberdeen (United Kingdom)

    2006-07-01

    The examination of production history from hydrocarbon fields composed of turbidite deposits indicates that fluid flow behaviour is often more complex than expected. The cause is commonly linked to the presence of fine-scale sedimentary heterogeneities, which complicate the reservoir. This is especially true in the case of turbiditic submarine channel complexes with final channel-filling stages composed of lateral migration deposits. These fine-scale heterogeneities are usually below seismic resolution and are rarely represented in initial reservoir models designed for such fields. Thus, it is difficult to match the production history or identify methods to improve production and reduce associated risks. The various depositional patterns recognized in channel migration and aggradation packages from the Oligocene Malembo Formation of the Congo Basin, offshore Angola, exhibit different dynamic responses when modelled in a reservoir simulator. These dynamic differences are related to the different preservation rates of bank collapse sediments within isolated channel bodies, hereafter referred to as 'elementary channels'. According to these preservation differences, the vertical stacking pattern of channels results in better connectivity than the true lateral migration. This effect has been incorporated into a full-field simulation model by applying petrophysical upscaling methods. The recognition and modelling of detailed sedimentological heterogeneities, and their distribution along full-field models produces a better history match when the inherent uncertainties have been taken into account. Incorporating all available data and concepts to define reservoir architecture is essential in understanding the impact that fine-scale heterogeneities have on reservoir management. As the lateral extent and areal distribution of heterogeneities is still unknown, our modelling workflow incorporates uncertainty in the form of multiple realizations to identify and

  12. Architecture Models and Data Flows in Local and Group Datawarehouses

    Science.gov (United States)

    Bogza, R. M.; Zaharie, Dorin; Avasilcai, Silvia; Bacali, Laura

    Architecture models and possible data flows for local and group datawarehouses are presented, together with some data processing models. The architecture models consists of several layers and the data flow between them. The choosen architecture of a datawarehouse depends on the data type and volumes from the source data, and inflences the analysis, data mining and reports done upon the data from DWH.

  13. Data Integration for the Generation of High Resolution Reservoir Models

    Energy Technology Data Exchange (ETDEWEB)

    Albert Reynolds; Dean Oliver; Gaoming Li; Yong Zhao; Chaohui Che; Kai Zhang; Yannong Dong; Chinedu Abgalaka; Mei Han

    2009-01-07

    The goal of this three-year project was to develop a theoretical basis and practical technology for the integration of geologic, production and time-lapse seismic data in a way that makes best use of the information for reservoir description and reservoir performance predictions. The methodology and practical tools for data integration that were developed in this research project have been incorporated into computational algorithms that are feasible for large scale reservoir simulation models. As the integration of production and seismic data require calibrating geological/geostatistical models to these data sets, the main computational tool is an automatic history matching algorithm. The following specific goals were accomplished during this research. (1) We developed algorithms for calibrating the location of the boundaries of geologic facies and the distribution of rock properties so that production and time-lapse seismic data are honored. (2) We developed and implemented specific procedures for conditioning reservoir models to time-lapse seismic data. (3) We developed and implemented algorithms for the characterization of measurement errors which are needed to determine the relative weights of data when conditioning reservoir models to production and time-lapse seismic data by automatic history matching. (4) We developed and implemented algorithms for the adjustment of relative permeability curves during the history matching process. (5) We developed algorithms for production optimization which accounts for geological uncertainty within the context of closed-loop reservoir management. (6) To ensure the research results will lead to practical public tools for independent oil companies, as part of the project we built a graphical user interface for the reservoir simulator and history matching software using Visual Basic.

  14. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2002-09-25

    The University of Alabama in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company are undertaking an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary objective of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. The principal research effort for Year 2 of the project has been reservoir characterization, 3-D modeling and technology transfer. This effort has included six tasks: (1) the study of rockfluid interactions, (2) petrophysical and engineering characterization, (3) data integration, (4) 3-D geologic modeling, (5) 3-D reservoir simulation and (6) technology transfer. This work was scheduled for completion in Year 2. Overall, the project work is on schedule. Geoscientific reservoir characterization is essentially completed. The architecture, porosity types and heterogeneity of the reef and shoal reservoirs at Appleton and Vocation Fields have been characterized using geological and geophysical data. The study of rock-fluid interactions is near completion. Observations regarding the diagenetic processes influencing pore system development and

  15. Model Structure Analysis of Model-based Operation of Petroleum Reservoirs

    NARCIS (Netherlands)

    Van Doren, J.F.M.

    2010-01-01

    The demand for petroleum is expected to increase in the coming decades, while the production of petroleum from subsurface reservoirs is becoming increasingly complex. To meet the demand petroleum reservoirs should be operated more efficiently. Physics-based petroleum reservoir models that describe t

  16. Model Structure Analysis of Model-based Operation of Petroleum Reservoirs

    NARCIS (Netherlands)

    Van Doren, J.F.M.

    2010-01-01

    The demand for petroleum is expected to increase in the coming decades, while the production of petroleum from subsurface reservoirs is becoming increasingly complex. To meet the demand petroleum reservoirs should be operated more efficiently. Physics-based petroleum reservoir models that describe

  17. Artificial neural network modeling of dissolved oxygen in reservoir.

    Science.gov (United States)

    Chen, Wei-Bo; Liu, Wen-Cheng

    2014-02-01

    The water quality of reservoirs is one of the key factors in the operation and water quality management of reservoirs. Dissolved oxygen (DO) in water column is essential for microorganisms and a significant indicator of the state of aquatic ecosystems. In this study, two artificial neural network (ANN) models including back propagation neural network (BPNN) and adaptive neural-based fuzzy inference system (ANFIS) approaches and multilinear regression (MLR) model were developed to estimate the DO concentration in the Feitsui Reservoir of northern Taiwan. The input variables of the neural network are determined as water temperature, pH, conductivity, turbidity, suspended solids, total hardness, total alkalinity, and ammonium nitrogen. The performance of the ANN models and MLR model was assessed through the mean absolute error, root mean square error, and correlation coefficient computed from the measured and model-simulated DO values. The results reveal that ANN estimation performances were superior to those of MLR. Comparing to the BPNN and ANFIS models through the performance criteria, the ANFIS model is better than the BPNN model for predicting the DO values. Study results show that the neural network particularly using ANFIS model is able to predict the DO concentrations with reasonable accuracy, suggesting that the neural network is a valuable tool for reservoir management in Taiwan.

  18. Characterization of fluvial sedimentology for reservoir simulation modeling

    Energy Technology Data Exchange (ETDEWEB)

    Henriquez, A.; Tyler, K.J.; Hurst, A. (Statoil, Stavanger (NO))

    1990-09-01

    This paper presents a critical study of 3D stochastic simulation of a fluvial reservoir and of the transfer of the geological model to a reservoir simulation grid. The stochastic model is conditioned by sand-body thickness and position in wellbores. Geological input parameters-sand-body orientation and width/thickness ratios-are often difficult to determine, and are invariably subject to interpretation. Net/gross ratio (NGR) and sand-body thickness are more easily estimated. Sand-body connectedness varies, depending on the modeling procedure; however, a sedimentary process-related model gives intermediate values for connectedness between the values for a regular packing model and the stochastic model. The geological model is transferred to a reservoir simulation grid by use of transmissibility multipliers and an NGR value for each block. The transfer of data smooths out much of the detailed geological information, and the calculated recovery factors are insensitive to the continuity measured in the geological model. Hence, the authors propose improvements to the interface between geological and reservoir simulation models.

  19. Integration of advanced geoscience and engineering techniques to quantify interwell heterogeneity in reservoir models. Final report, September 29, 1993--September 30, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, W.W.; Buckley, J.S.; Ouenes, A.

    1997-05-01

    The goal of this three-year project was to provide a quantitative definition of reservoir heterogeneity. This objective was accomplished through the integration of geologic, geophysical, and engineering databases into a multi-disciplinary understanding of reservoir architecture and associated fluid-rock and fluid-fluid interactions. This interdisciplinary effort integrated geological and geophysical data with engineering and petrophysical results through reservoir simulation to quantify reservoir architecture and the dynamics of fluid-rock and fluid-fluid interactions. An improved reservoir description allows greater accuracy and confidence during simulation and modeling as steps toward gaining greater recovery efficiency from existing reservoirs. A field laboratory, the Sulimar Queen Unit, was available for the field research. Several members of the PRRC staff participated in the development of improved reservoir description by integration of the field and laboratory data as well as in the development of quantitative reservoir models to aid performance predictions. Subcontractors from Stanford University and the University of Texas at Austin (UT) collaborated in the research and participated in the design and interpretation of field tests. The three-year project was initiated in September 1993 and led to the development and application of various reservoir description methodologies. A new approach for visualizing production data graphically was developed and implemented on the Internet. Using production data and old gamma rays logs, a black oil reservoir model that honors both primary and secondary performance was developed. The old gamma ray logs were used after applying a resealing technique, which was crucial for the success of the project. In addition to the gamma ray logs, the development of the reservoir model benefitted from an inverse Drill Stem Test (DST) technique which provided initial estimates of the reservoir permeability at different wells.

  20. MATHEMATICAL MODELLING OF DEGRADATION AND FLUVIAL PROCESS DOWNSTREAM RESERVOIRS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    To research into the problem of degradation and fluvial process downstream reservoirs and its influence on flood control and navigation, a 1-D mathematical model of degradation and fluvial process downstream the reservoir was established in this paper. The non-equilibrium transport of non-uniform suspended load, the non-uniform bedload transport and bed material sorting were considered in the model. Some techniques were suggested for some problems in calculation, such as the effective suspended load carrying capacity of the different reaches of bed materials, the coefficient of suspended load carrying capacity, the recovering coefficient of carrying capacity, the mixed layer thickness, the bedload transport width, bifurcation and confluence of main and branch channel, and the distribution of deposition and erosion along the cross section, etc. The model was tested by the data of degradation downstream the Danjiangkou reservoir on the Hanjiang River and the data of degradation downstream the Gezhouba Project on the Yangtze River.

  1. Mathematical analysis of a muscle architecture model.

    Science.gov (United States)

    Navallas, Javier; Malanda, Armando; Gila, Luis; Rodríguez, Javier; Rodríguez, Ignacio

    2009-01-01

    Modeling of muscle architecture, which aims to recreate mathematically the physiological structure of the muscle fibers and motor units, is a powerful tool for understanding and modeling the mechanical and electrical behavior of the muscle. Most of the published models are presented in the form of algorithms, without mathematical analysis of mechanisms or outcomes of the model. Through the study of the muscle architecture model proposed by Stashuk, we present the analytical tools needed to better understand these models. We provide a statistical description for the spatial relations between motor units and muscle fibers. We are particularly concerned with two physiological quantities: the motor unit fiber number, which we expect to be proportional to the motor unit territory area; and the motor unit fiber density, which we expect to be constant for all motor units. Our results indicate that the Stashuk model is in good agreement with the physiological evidence in terms of the expectations outlined above. However, the resulting variance is very high. In addition, a considerable 'edge effect' is present in the outer zone of the muscle cross-section, making the properties of the motor units dependent on their location. This effect is relevant when motor unit territories and muscle cross-section are of similar size.

  2. Regional implications of the Bashkerian-Serpukhovian reservoir architecture at Tengiz field; Kazakhstan

    Energy Technology Data Exchange (ETDEWEB)

    Lomando, A.J. [Chevron Overseas Petroleum Inc., San Ramon, CA (United States); Suisenov, K. [Tengizchevroil, Tengiz (Kazakhstan); Shilin, A. [VolgogradNIPIneft Institute, Volgograd (Russian Federation)

    1995-08-01

    The super-giant Tengiz Field is a complex Carboniferous-Devonian reservoir. The most common occurrence of higher porosity zones is in the uppermost portion of the reservoir within the Bashkerian to Serpukhovian section. The suite of porous textures containing preserved primary porosity ranges from skeletal and coated grain to mixed particle grainstones, and packstones which display little or no compaction due to early isopachous marine cementation. In some areas, the amount of primary preserved porosity is inversely proportional to th occurrence and amount of crinoids and associated syntaxial overgrowths. Early and late secondary porosity is most pronounced in the upper portions of the reservoir associated with features ranging from multiple short-term exposure events to long-duration unconformities. Lower energy wackestones and mudstones interbedded with higher energy facies cause verticle permeability barriers and baffles. In areas of stacked shoaling cycles in the platform interior, lateral correlation of porosity zones is good. Muddy biolithites tend to be concentrated along the north and eastern portions of the structure and generally contain lower reservoir quality and cause lateral changes in reservoir continuity. Preliminary analysis of facies distribution patterns indicates that the higher energy {open_quotes}windward{close_quotes} direction is not facing into the North Caspian basin, but to the east-northeast into the Emba sub-basin. This allows for a separate exploration play concept around the Emba sub-basin {open_quotes}rim{close_quotes} which would be separate and distinct from the rest of the North Caspian Basin.

  3. Enhancing Architectural Drawings and Models with Photoshop

    CERN Document Server

    Onstott, Scott

    2010-01-01

    Transform your CAD drawings into powerful presentationThis one-of-a-kind book shows you how to use Photoshop to turn CAD drawings and BIM models into artistic presentations with captivating animations, videos, and dynamic 3D imagery. The techniques apply to all leading architectural design software including AutoCAD, Revit, and 3ds Max Design. Video tutorials on the DVD improve your learning curve and let you compare your work with the author's.Turn CAD drawings and BIM models into powerful presentations featuring animation, videos, and 3D imagery for enhanced client appealCraft interactive pa

  4. Modelling and using product architectures in mechatronic product development

    DEFF Research Database (Denmark)

    Bruun, Hans Peter Lomholt; Mortensen, Niels Henrik

    , experiences by using the architecture representation in a mechatronic development project, and the scope of using the architecture model as a skeleton for a data structure in a PLM system. The fundamental idea for planning and modeling holistic architectures is that an improved understanding of the whole...

  5. Storage Capacity Modeling of Reservoir Systems Employing Performance Measures

    Directory of Open Access Journals (Sweden)

    Issa Saket Oskoui

    2014-12-01

    Full Text Available Developing a prediction relationship for total (i.e. within-year plus over-year storage capacity of reservoir systems is beneficial because it can be used as an alternative to the analysis of reservoirs during designing stage and gives an opportunity to planner to examine and compare different cases in a fraction of time required for complete analysis where detailed analysis is not necessary. Existing relationships for storage capacity are mostly capable of estimating over-year storage capacity and total storage capacity can be obtained through relationships for adjusting over-year capacity and there is no independent relationship to estimate total storage capacity. Moreover these relationships do not involve vulnerability performance criterion and are not verified for Malaysia Rivers. In this study two different reservoirs in Southern part of Peninsular Malaysia, Melaka and Muar, are analyzed through a Monte Carlo simulation approach involving performance metrics. Subsequently the storage capacity results of the simulation are compared with those of the well-known existing equations. It is observed that existing models may not predict total capacity appropriately for Malaysian reservoirs. Consequently, applying the simulation results, two separate regression equations are developed to model total storage capacity of study reservoirs employing time based reliability and vulnerability performance measures.

  6. Generation of reservoir models on flexible meshes; Generation de modeles de reservoir sur maillage flexible

    Energy Technology Data Exchange (ETDEWEB)

    Ricard, L.

    2005-12-15

    The high level geo-statistic description of the subsurface are often far too detailed for use in routine flow simulators. To make flow simulations tractable, the number of grid blocks has to be reduced: an approximation, still relevant with flow description, is necessary. In this work, we place the emphasis on the scaling procedure from the fine scale model to the multi-scale reservoir model. Two main problems appear: Near wells, faults and channels, the volume of flexible cells may be less than fine ones, so we need to solve a down-scaling problem; Far from these regions, the volume of cells are bigger than fine ones so we need to solve an up-scaling problem. In this work, research has been done on each of these three areas: down-scaling, up-scaling and fluid flow simulation. For each of these subjects, a review, some news improvements and comparative study are proposed. The proposed down-scaling method is build to be compatible with existing data integration methods. The comparative study shows that empirical methods are not enough accurate to solve the problem. Concerning the up-scaling step, the proposed approach is based on an existing method: the perturbed boundary conditions. An extension to unstructured mesh is developed for the inter-cell permeability tensor. The comparative study shows that numerical methods are not always as accurate as expected and the empirical model can be sufficient in lot of cases. A new approach to single-phase fluid flow simulation is developed. This approach can handle with full tensorial permeability fields with source or sink terms.(author)

  7. Parallel, Multigrid Finite Element Simulator for Fractured/Faulted and Other Complex Reservoirs based on Common Component Architecture (CCA)

    Energy Technology Data Exchange (ETDEWEB)

    Milind Deo; Chung-Kan Huang; Huabing Wang

    2008-08-31

    Black-oil, compositional and thermal simulators have been developed to address different physical processes in reservoir simulation. A number of different types of discretization methods have also been proposed to address issues related to representing the complex reservoir geometry. These methods are more significant for fractured reservoirs where the geometry can be particularly challenging. In this project, a general modular framework for reservoir simulation was developed, wherein the physical models were efficiently decoupled from the discretization methods. This made it possible to couple any discretization method with different physical models. Oil characterization methods are becoming increasingly sophisticated, and it is possible to construct geologically constrained models of faulted/fractured reservoirs. Discrete Fracture Network (DFN) simulation provides the option of performing multiphase calculations on spatially explicit, geologically feasible fracture sets. Multiphase DFN simulations of and sensitivity studies on a wide variety of fracture networks created using fracture creation/simulation programs was undertaken in the first part of this project. This involved creating interfaces to seamlessly convert the fracture characterization information into simulator input, grid the complex geometry, perform the simulations, and analyze and visualize results. Benchmarking and comparison with conventional simulators was also a component of this work. After demonstration of the fact that multiphase simulations can be carried out on complex fracture networks, quantitative effects of the heterogeneity of fracture properties were evaluated. Reservoirs are populated with fractures of several different scales and properties. A multiscale fracture modeling study was undertaken and the effects of heterogeneity and storage on water displacement dynamics in fractured basements were investigated. In gravity-dominated systems, more oil could be recovered at a given pore

  8. The Permian Rotliegend reservoir architecture of the Dutch Koekoekspolder geothermal doublet

    NARCIS (Netherlands)

    Mijnlieff, H.F.; Bloemsma, M.R.; Donselaar, M.E.; Henares, S.; Redjosentono, A.E.; Veldkamp, J.G.; Weltje, G.J.

    2014-01-01

    The Dutch Koekoekspolder geothermal doublet was drilled in 2011 targeting the Permian Rotliegendreservoir. The encountered reservoir properties were less favorable than expected pre-drill. Post-drill integrated evaluation of vintage data and the new data from the geothermal wells resulted in a refin

  9. Architecture of an Upper Jurassic barrier island sandstone reservoir, Danish Central Graben:

    DEFF Research Database (Denmark)

    Johannessen, Peter N.; Nielsen, Lars H.; Nielsen, Lars

    2010-01-01

    An unusually thick (c. 88 m), transgressive barrier island and shoreface sandstone succession characterizes the Upper Jurassic Heno Formation reservoir of the Freja oil field situated on the boundary of Denmark and Norway. The development and preservation of such thick transgressive barrier islan...... such that the island aggraded and even prograded seawards and became wider and longer due to the large surplus of sand....

  10. Grid architecture model of network centric warfare

    Institute of Scientific and Technical Information of China (English)

    Yan Tihua; Wang Baoshu

    2006-01-01

    NCW(network centric warfare) is an information warfare concentrating on network. A global network-centric warfare architecture with OGSA grid technology is put forward, which is a four levels system including the user level, the application level, the grid middleware layer and the resource level. In grid middleware layer, based on virtual hosting environment, a BEPL4WS grid service composition method is introduced. In addition, the NCW grid service model is built with the help of Eclipse-SDK-3.0.1 and Bpws4j.

  11. Modeling reservoir density underflow and interflow from a chemical spill

    Science.gov (United States)

    Gu, R.; McCutcheon, S.C.; Wang, P.-F.

    1996-01-01

    An integral simulation model has been developed for understanding and simulating the process of a density current and the transport of spilled chemicals in a stratified reservoir. The model is capable of describing flow behavior and mixing mechanisms in different flow regimes (plunging flow, underflow, and interflow). It computes flow rate, velocity, flow thickness, mixing parameterized by entrainment and dilution, depths of plunging, separation and intrusion, and time of travel. The model was applied to the Shasta Reservoir in northern California during the July 1991 Sacramento River chemical spill. The simulations were used to assist in the emergency response, confirm remediation measures, and guide data collection. Spill data that were available after the emergency response are used to conduct a postaudit of the model results. Predicted flow parameters are presented and compared with observed interflow intrusion depth, travel time, and measured concentrations of spilled chemicals. In the reservoir, temperature difference between incoming river flow and ambient lake water played a dominant role during the processes of flow plunging, separation, and intrusion. With the integral approach, the gross flow behavior can be adequately described and information useful in the analysis of contaminated flow in a reservoir after a spill is provided.

  12. Ensemble-based conditioning of reservoir models to seismic data

    NARCIS (Netherlands)

    Leeuwenburgh, O.; Brouwer, J.; Trani, M.

    2011-01-01

    While 3D seismic has been the basis for geological model building for a long time, time-lapse seismic has primarily been used in a qualitative manner to assist in monitoring reservoir behavior. With the growing acceptance of assisted history matching methods has come an equally rising interest in in

  13. Ensemble-based conditioning of reservoir models to seismic data

    NARCIS (Netherlands)

    Leeuwenburgh, O.; Brouwer, J.; Trani, M.

    2010-01-01

    While 3D seismic has been the basis for geological model building for a long time, time-lapse seismic has primarily been used in a qualitative manner to assist in monitoring reservoir behavior. With the growing acceptance of assisted history matching methods has come an equally rising interest in in

  14. The architecture modeling of LAMOST Observatory control system

    Science.gov (United States)

    Wang, Jian; Jin, Ge; Huang, Kun; Li, Feng; Ren, Jian; Yu, Xiao-Qi

    2005-06-01

    For the complexity of the LAMOST, long time development for the LAMOST and long life-cycle of the OCS system, the OCS must have a flexible, extensible, maintainable software system. It is required that the OCS has a flexible and extensible architecture. In this paper the concepts of architecture and the OCS are introduced. Referring many kinds of architecture pattern and based on the OCS physical models, the architecture of the OCS is established which is a component-based layered system using many patterns such as the MVC and proxy. The static model and dynamic model of architecture are discussed and realized at the phase of 1 level OCS.

  15. Geothermal reservoir engineering. 5. Reservoir simulation (natural state modeling); Chinetsu choryuso kogaku. 5. Choryuso simulation (shizen jotai modeling)

    Energy Technology Data Exchange (ETDEWEB)

    Ishido, T. [Geological Survey of Japan, Tsukuba (Japan)

    1998-03-15

    This paper explains natural state modeling in reservoir simulation. A geothermal reservoir is composed of a mixture of two phases of liquid or liquid and steam, where the geothermal system is characterized by rising flow of fluid from deeper portions. The two-phase system is created by depressurization of the fluid due to the rising flow, followed by boiling at a certain depth. The steam phase continues rising in the vertical direction to form a steam zone, while the liquid phase flow in the horizontal direction and flows out as springs in remote distances. To quantify the description of such conception model, simulation in natural condition is important. The natural state simulation is a means to integrate different data and structure a mathematical model for the reservoir. The derived mathematical model results in quantification of the conception model, and reproduction of dynamics in the natural condition. The mathematical model may be used as a base when the estimating calculations are carried out on reservoir behavior after having started production and reduction. 9 refs., 16 figs., 8 tabs.

  16. Evaluation of Gaussian approximations for data assimilation in reservoir models

    KAUST Repository

    Iglesias, Marco A.

    2013-07-14

    The Bayesian framework is the standard approach for data assimilation in reservoir modeling. This framework involves characterizing the posterior distribution of geological parameters in terms of a given prior distribution and data from the reservoir dynamics, together with a forward model connecting the space of geological parameters to the data space. Since the posterior distribution quantifies the uncertainty in the geologic parameters of the reservoir, the characterization of the posterior is fundamental for the optimal management of reservoirs. Unfortunately, due to the large-scale highly nonlinear properties of standard reservoir models, characterizing the posterior is computationally prohibitive. Instead, more affordable ad hoc techniques, based on Gaussian approximations, are often used for characterizing the posterior distribution. Evaluating the performance of those Gaussian approximations is typically conducted by assessing their ability at reproducing the truth within the confidence interval provided by the ad hoc technique under consideration. This has the disadvantage of mixing up the approximation properties of the history matching algorithm employed with the information content of the particular observations used, making it hard to evaluate the effect of the ad hoc approximations alone. In this paper, we avoid this disadvantage by comparing the ad hoc techniques with a fully resolved state-of-the-art probing of the Bayesian posterior distribution. The ad hoc techniques whose performance we assess are based on (1) linearization around the maximum a posteriori estimate, (2) randomized maximum likelihood, and (3) ensemble Kalman filter-type methods. In order to fully resolve the posterior distribution, we implement a state-of-the art Markov chain Monte Carlo (MCMC) method that scales well with respect to the dimension of the parameter space, enabling us to study realistic forward models, in two space dimensions, at a high level of grid refinement. Our

  17. Assessing the impacts of reservoir operation to floodplain inundation by combining hydrological, reservoir management, and hydrodynamic models

    Science.gov (United States)

    Mateo, Cherry May; Hanasaki, Naota; Komori, Daisuke; Tanaka, Kenji; Kiguchi, Masashi; Champathong, Adisorn; Sukhapunnaphan, Thada; Yamazaki, Dai; Oki, Taikan

    2014-09-01

    A catastrophic flood event which caused massive economic losses occurred in Thailand, in 2011. Several studies have already been conducted to analyze the Thai floods, but none of them have assessed the impacts of reservoir operation on flood inundation. This study addresses this gap by combining physically based hydrological models to explicitly simulate the impacts of reservoir operation on flooding in the Chao Phraya River Basin, Thailand. H08, an integrated water resources model with a reservoir operation module, was combined with CaMa-Flood, a river routing model with representation of flood dynamics. The combined H08-CaMa model was applied to simulate and assess the historical and alternative reservoir operation rules in the two largest reservoirs in the basin. The combined H08-CaMa model effectively simulated the 2011 flood: regulated flows at a major gauging station have high daily NSE-coefficient of 92% as compared with observed discharge; spatiotemporal extent of simulated flood inundation match well with those of satellite observations. Simulation results show that through the operation of reservoirs in 2011, flood volume was reduced by 8.6 billion m3 and both depth and area of flooding were reduced by 40% on the average. Nonetheless, simple modifications in reservoir operation proved to further reduce the flood volume by 2.4 million m3 and the depth and area of flooding by 20% on the average. By modeling reservoir operation with a hydrodynamic model, a more realistic simulation of the 2011 Thai flood was made possible, and the potential of reducing flood inundation through improved reservoir management was quantified.

  18. A Comprehensive Model for Evaluating Coalbed Methane Reservoirs in China

    Institute of Scientific and Technical Information of China (English)

    YAO Yanbin; LIU Dameng; TANG Dazhen; HUANG Wenhui; TANG Shuheng; CHE Yao

    2008-01-01

    Coalbed methane reservoir (CBMR) evaluation is important for choosing the prospective target area for coalbed methane exploration and production. This study aims at identifying the characteristic parameters and methods to evaluate CBMR. Based on the geological surveys, laboratory measurements and field works, a four-level analytic hierarchy process (AHP) model for CBMR evaluation is proposed. In this model, different weights are prioritized and assigned on the basis of three main criteria (including reservoir physical property, storage capacity and geological characteristics), 15 sub-criteria, and 18 technical alternatives; the later of which are discussed in detail. The model was applied to evaluate the CBMR of the Permo-Carboniferous coals in the Qinshui Basin, North China. This GIS-based fuzzy AHP comprehensive model can be used for the evaluation of CBMR of medium-high rank (mean maximum vitrinite reflectance >0.5%) coal districts in China.

  19. Evaluation of field development plans using 3-D reservoir modelling

    Energy Technology Data Exchange (ETDEWEB)

    Seifert, D.; Lewis, J.J.M. [Heriot-Watt Univ., Edinburgh (United Kingdom); Newbery, J.D.H. [Conoco, UK Ltd., Aberdeen (United Kingdom)] [and others

    1997-08-01

    Three-dimensional reservoir modelling has become an accepted tool in reservoir description and is used for various purposes, such as reservoir performance prediction or integration and visualisation of data. In this case study, a small Northern North Sea turbiditic reservoir was to be developed with a line drive strategy utilising a series of horizontal producer and injector pairs, oriented north-south. This development plan was to be evaluated and the expected outcome of the wells was to be assessed and risked. Detailed analyses of core, well log and analogue data has led to the development of two geological {open_quotes}end member{close_quotes} scenarios. Both scenarios have been stochastically modelled using the Sequential Indicator Simulation method. The resulting equiprobable realisations have been subjected to detailed statistical well placement optimisation techniques. Based upon bivariate statistical evaluation of more than 1000 numerical well trajectories for each of the two scenarios, it was found that the wells inclinations and lengths had a great impact on the wells success, whereas the azimuth was found to have only a minor impact. After integration of the above results, the actual well paths were redesigned to meet external drilling constraints, resulting in substantial reductions in drilling time and costs.

  20. ADVANCED TECHNIQUES FOR RESERVOIR SIMULATION AND MODELING OF NONCONVENTIONAL WELLS

    Energy Technology Data Exchange (ETDEWEB)

    Louis J. Durlofsky; Khalid Aziz

    2004-08-20

    Nonconventional wells, which include horizontal, deviated, multilateral and ''smart'' wells, offer great potential for the efficient management of oil and gas reservoirs. These wells are able to contact larger regions of the reservoir than conventional wells and can also be used to target isolated hydrocarbon accumulations. The use of nonconventional wells instrumented with downhole inflow control devices allows for even greater flexibility in production. Because nonconventional wells can be very expensive to drill, complete and instrument, it is important to be able to optimize their deployment, which requires the accurate prediction of their performance. However, predictions of nonconventional well performance are often inaccurate. This is likely due to inadequacies in some of the reservoir engineering and reservoir simulation tools used to model and optimize nonconventional well performance. A number of new issues arise in the modeling and optimization of nonconventional wells. For example, the optimal use of downhole inflow control devices has not been addressed for practical problems. In addition, the impact of geological and engineering uncertainty (e.g., valve reliability) has not been previously considered. In order to model and optimize nonconventional wells in different settings, it is essential that the tools be implemented into a general reservoir simulator. This simulator must be sufficiently general and robust and must in addition be linked to a sophisticated well model. Our research under this five year project addressed all of the key areas indicated above. The overall project was divided into three main categories: (1) advanced reservoir simulation techniques for modeling nonconventional wells; (2) improved techniques for computing well productivity (for use in reservoir engineering calculations) and for coupling the well to the simulator (which includes the accurate calculation of well index and the modeling of multiphase flow

  1. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2001-09-14

    The University of Alabama in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company are undertaking an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary objective of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. The principal research effort for Year 1 of the project has been reservoir description and characterization. This effort has included four tasks: (1) geoscientific reservoir characterization, (2) the study of rock-fluid interactions, (3) petrophysical and engineering characterization and (4) data integration. This work was scheduled for completion in Year 1. Overall, the project work is on schedule. Geoscientific reservoir characterization is essentially completed. The architecture, porosity types and heterogeneity of the reef and shoal reservoirs at Appleton and Vocation Fields have been characterized using geological and geophysical data. The study of rock-fluid interactions has been initiated. Observations regarding the diagenetic processes influencing pore system development and heterogeneity in these reef and shoal reservoirs have been

  2. PHYSICAL MODELING OF HYDRAULIC DESILTATION IN TAPU RESERVOIR

    Institute of Scientific and Technical Information of China (English)

    Jihn-Sung LAI; Fi-John CHANG

    2001-01-01

    A movable bed physical model was constructed to investigate hydraulic desiltation by flushing and lateral erosion in the Tapu reservoir, Taiwan. The model scaling is based on the requirement for dynamic similarity of cohesive sediment deposit initiation in flushing processes. For model scaling,flume experiments investigating the initiation of cohesive sediment deposits were carried out to establish the relationship between critical shear stress of the flow and dry density of the deposit.Experiments in the physical model were then performed to measure the variations of the reservoir water level, the outlet discharge and the outflow sediment discharge. The processes of emptying and flushing were observed and analyzed in the main flushing channel. One of the experiments was conducted to simulate the on-site flushing operations on June 11, 1997. The results showed that the total cumulative flushed sediment volume by physical modeling was close to that by numerical simulation. To deal with the floodplain deposits, experiments of lateral erosion as an auxiliary method were also conducted in the physical model to investigate the effectiveness and applicability for the Tapu reservoir.

  3. Three-Dimensional Modeling of Fracture Clusters in Geothermal Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Ghassemi, Ahmad [Univ. of Oklahoma, Norman, OK (United States)

    2017-08-11

    The objective of this is to develop a 3-D numerical model for simulating mode I, II, and III (tensile, shear, and out-of-plane) propagation of multiple fractures and fracture clusters to accurately predict geothermal reservoir stimulation using the virtual multi-dimensional internal bond (VMIB). Effective development of enhanced geothermal systems can significantly benefit from improved modeling of hydraulic fracturing. In geothermal reservoirs, where the temperature can reach or exceed 350oC, thermal and poro-mechanical processes play an important role in fracture initiation and propagation. In this project hydraulic fracturing of hot subsurface rock mass will be numerically modeled by extending the virtual multiple internal bond theory and implementing it in a finite element code, WARP3D, a three-dimensional finite element code for solid mechanics. The new constitutive model along with the poro-thermoelastic computational algorithms will allow modeling the initiation and propagation of clusters of fractures, and extension of pre-existing fractures. The work will enable the industry to realistically model stimulation of geothermal reservoirs. The project addresses the Geothermal Technologies Office objective of accurately predicting geothermal reservoir stimulation (GTO technology priority item). The project goal will be attained by: (i) development of the VMIB method for application to 3D analysis of fracture clusters; (ii) development of poro- and thermoelastic material sub-routines for use in 3D finite element code WARP3D; (iii) implementation of VMIB and the new material routines in WARP3D to enable simulation of clusters of fractures while accounting for the effects of the pore pressure, thermal stress and inelastic deformation; (iv) simulation of 3D fracture propagation and coalescence and formation of clusters, and comparison with laboratory compression tests; and (v) application of the model to interpretation of injection experiments (planned by our

  4. Executable Architecture Modeling and Simulation Based on fUML

    Science.gov (United States)

    2014-06-01

    informal constructs. The paper proposes an approach of executable architecture modeling and simulation by introducing formal UML specification. Firstly...ones. UML is accepted as an Architectural Description Language by architects, and it has become a standard notation to document the architecture...these UML models are not executable. Object Management Group proposes the fUML to enable UML models execution [5]. Accordingly, we propose an

  5. CATS - A process-based model for turbulent turbidite systems at the reservoir scale

    Science.gov (United States)

    Teles, Vanessa; Chauveau, Benoît; Joseph, Philippe; Weill, Pierre; Maktouf, Fakher

    2016-09-01

    The Cellular Automata for Turbidite systems (CATS) model is intended to simulate the fine architecture and facies distribution of turbidite reservoirs with a multi-event and process-based approach. The main processes of low-density turbulent turbidity flow are modeled: downslope sediment-laden flow, entrainment of ambient water, erosion and deposition of several distinct lithologies. This numerical model, derived from (Salles, 2006; Salles et al., 2007), proposes a new approach based on the Rouse concentration profile to consider the flow capacity to carry the sediment load in suspension. In CATS, the flow distribution on a given topography is modeled with local rules between neighboring cells (cellular automata) based on potential and kinetic energy balance and diffusion concepts. Input parameters are the initial flow parameters and a 3D topography at depositional time. An overview of CATS capabilities in different contexts is presented and discussed.

  6. Uncertainty analysis of fluvial outcrop data for stochastic reservoir modelling

    Energy Technology Data Exchange (ETDEWEB)

    Martinius, A.W. [Statoil Research Centre, Trondheim (Norway); Naess, A. [Statoil Exploration and Production, Stjoerdal (Norway)

    2005-07-01

    Uncertainty analysis and reduction is a crucial part of stochastic reservoir modelling and fluid flow simulation studies. Outcrop analogue studies are often employed to define reservoir model parameters but the analysis of uncertainties associated with sedimentological information is often neglected. In order to define uncertainty inherent in outcrop data more accurately, this paper presents geometrical and dimensional data from individual point bars and braid bars, from part of the low net:gross outcropping Tortola fluvial system (Spain) that has been subjected to a quantitative and qualitative assessment. Four types of primary outcrop uncertainties are discussed: (1) the definition of the conceptual depositional model; (2) the number of observations on sandstone body dimensions; (3) the accuracy and representativeness of observed three-dimensional (3D) sandstone body size data; and (4) sandstone body orientation. Uncertainties related to the depositional model are the most difficult to quantify but can be appreciated qualitatively if processes of deposition related to scales of time and the general lack of information are considered. Application of the N0 measure is suggested to assess quantitatively whether a statistically sufficient number of dimensional observations is obtained to reduce uncertainty to an acceptable level. The third type of uncertainty is evaluated in a qualitative sense and determined by accurate facies analysis. The orientation of sandstone bodies is shown to influence spatial connectivity. As a result, an insufficient number or quality of observations may have important consequences for estimated connected volumes. This study will give improved estimations for reservoir modelling. (author)

  7. Extending enterprise architecture modelling with business goals and requirements

    NARCIS (Netherlands)

    Engelsman, Wilco; Quartel, Dick; Jonkers, Henk; Sinderen, van Marten

    2011-01-01

    The methods for enterprise architecture (EA), such as The Open Group Architecture Framework, acknowledge the importance of requirements modelling in the development of EAs. Modelling support is needed to specify, document, communicate and reason about goals and requirements. The current modelling te

  8. Proactive Modeling of Market, Product and Production Architectures

    DEFF Research Database (Denmark)

    Mortensen, Niels Henrik; Hansen, Christian Lindschou; Hvam, Lars;

    2011-01-01

    This paper presents an operational model that allows description of market, products and production architectures. The main feature of this model is the ability to describe both structural and functional aspect of architectures. The structural aspect is an answer to the question: What constitutes...... the architecture, e.g. standard designs, design units and interfaces? The functional aspect is an answer to the question: What is the behaviour or the architecture, what is it able to do, i.e. which products at which performance levels can be derived from the architecture? Among the most important benefits...... of this model is the explicit ability to describe what the architecture is prepared for, and what it is not prepared for - concerning development of future derivative products. The model has been applied in a large scale global product development project. Among the most important benefits is contribution to...

  9. Reservoir Stochastic Modeling Constrained by Quantitative Geological Conceptual Patterns

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    This paper discusses the principles of geologic constraints on reservoir stochastic modeling. By using the system science theory, two kinds of uncertainties, including random uncertainty and fuzzy uncertainty, are recognized. In order to improve the precision of stochastic modeling and reduce the uncertainty in realization, the fuzzy uncertainty should be stressed, and the "geological genesis-controlled modeling" is conducted under the guidance of a quantitative geological pattern. An example of the Pingqiao horizontal-well division of the Ansai Oilfield in the Ordos Basin is taken to expound the method of stochastic modeling.

  10. Formal Modeling for Information Appliance Using Abstract MVC Architecture

    OpenAIRE

    Arichika, Yuji; Araki, Keijiro

    2004-01-01

    In information appliance development, it is important to divide core functions and display functions because information appliance have various user interface and display functions changed frequently. Using MVC architecture is one way to divide display functions and core functions. But MVC architecture is implementation architecture and there are some gaps to get abstract model. On the other hand it is known that formal methods are useful for constructing abstract model. Therefore we intend t...

  11. Scalable and Robust BDDC Preconditioners for Reservoir and Electromagnetics Modeling

    KAUST Repository

    Zampini, S.

    2015-09-13

    The purpose of the study is to show the effectiveness of recent algorithmic advances in Balancing Domain Decomposition by Constraints (BDDC) preconditioners for the solution of elliptic PDEs with highly heterogeneous coefficients, and discretized by means of the finite element method. Applications to large linear systems generated by div- and curl- conforming finite elements discretizations commonly arising in the contexts of modelling reservoirs and electromagnetics will be presented.

  12. Optimization of Multipurpose Reservoir Systems Using Power Market Models

    DEFF Research Database (Denmark)

    Pereira-Cardenal, S. J.; Mo, B.; Riegels, N.

    2015-01-01

    optimal operation rules that maximize current and expected future benefits as a function of reservoir level, week of the year, and inflow state. The method was tested on the Iberian Peninsula and performed better than traditional approaches that use exogenous prices: resulting operation rules were more...... realistic and sensitive to hydrological variability. Internally calculated hydropower prices provided better results than exogenous hydropower prices and can therefore improve the representation of hydropower benefits in hydroeconomic models. (C) 2014 American Society of Civil Engineers....

  13. Business Model Design of Architectural Service Firms

    NARCIS (Netherlands)

    Bos-de Vos, M.; Lieftink, B.; Volker, L.; Wamelink, J.W.F.

    2014-01-01

    Due to significant changes in the architecture, engineering and construction industry, architectural firms have to adapt quickly to stay competitive. They need to innovate not only their products and services, but also make more fundamental changes in the way they create and appropriate value, there

  14. 3D-models in landscape architecture

    NARCIS (Netherlands)

    Nijhuis, S.; Stellingwerff, M.C.

    2011-01-01

    Landscape architecture consists of a basic attitude that involves four principles of study and practice. These are: anamnesis (palimpsest), process, three-dimensional space and scale-continuum (relational context). The core of landscape architecture as a design discipline is the construction and art

  15. From enterprise architecture to business models and back

    NARCIS (Netherlands)

    Iacob, Maria Eugenia; Meertens, Lucas Onno; Jonkers, H.; Quartel, Dick; Nieuwenhuis, Lambertus Johannes Maria; van Sinderen, Marten J.

    2014-01-01

    In this study, we argue that important IT change processes affecting an organization’s enterprise architecture are also mirrored by a change in the organization’s business model. An analysis of the business model may establish whether the architecture change has value for the business. Therefore, in

  16. Defining Generic Architecture for Cloud Infrastructure as a Service model

    NARCIS (Netherlands)

    Demchenko, Y.; de Laat, C.

    2011-01-01

    Infrastructure as a Service (IaaS) is one of the provisioning models for Clouds as defined in the NIST Clouds definition. Although widely used, current IaaS implementations and solutions doesn’t have common and well defined architecture model. The paper attempts to define a generic architecture for

  17. From enterprise architecture to business models and back

    NARCIS (Netherlands)

    Iacob, Maria Eugenia; Meertens, Lucas Onno; Jonkers, H.; Quartel, Dick; Nieuwenhuis, Lambertus Johannes Maria; van Sinderen, Marten J.

    In this study, we argue that important IT change processes affecting an organization’s enterprise architecture are also mirrored by a change in the organization’s business model. An analysis of the business model may establish whether the architecture change has value for the business. Therefore, in

  18. Defining generic architecture for Cloud IaaS provisioning model

    NARCIS (Netherlands)

    Y. Demchenko; C. de Laat; A. Mavrin

    2011-01-01

    Infrastructure as a Service (IaaS) is one of the provisioning models for Clouds as defined in the NIST Clouds definition. Although widely used, current IaaS implementations and solutions doesn’t have common and well defined architecture model. The paper attempts to define a generic architecture for

  19. Models of Geothermal Reservoirs as a Basis for Interdisciplinary Cooperation

    Science.gov (United States)

    Hoerdt, A.; Beilecke, T.; Ghergut, J.; Holzbecher, E.; Löhken, J.; Löhken, I.; Musmann, P.; Philipp, S. L.; Sauter, M.; Reyer, D.; Schaumann, G.; Thomas, R.

    2011-12-01

    Geophysical investigation and numerical simulation of various processes such as hydromechanics, hydrogeochemistry and heat flow are necessary to assess the prospects and improve the concepts of geothermal exploitation. The numerical simulation is based on models of geothermal reservoirs, where the geometry and physical properties of different formations are specified. The properties of drill holes, such as geometry and coupling to the formation, are also included. Here, we present a set of models that was defined within the German research consortium "geothermal energy and high-performance drilling technology" (gebo), sponsored by Baker Hughes and the Ministry of Science and Culture of Lower Saxony, Germany. Providing a standard set of models is essential to achieve the maximum possible exchange between the scientific disciplines and to obtain realistic and meaningful simulation results. The models are structured into three categories: large fault zones with increased hydraulic permeability, deep aquifers, which are characterised by a natural permittivity sufficient for geothermal exploitation, and petrothermal systems, where permittivity must be enhanced by hydraulic fracturing. We illustrate the simulation of different processes with a model of a large fault system, which was derived from seismic data and geological information, and specified within a commercial finite-element package. Stress field, heat flow and geophysical investigation were all simulated based on the same structure. For the reservoir categories "deep aquifer" and "petrothermal systems" we defined extremal models which represent the potentially deepest and hottest reservoirs in the North German sedimentary basin that constitute reasonable aims for drilling. Such models are essential for a regional strategy for the exploitation of geothermal energy.

  20. Forward modeling of seepage of reservoir dam based on ground penetrating radar

    Directory of Open Access Journals (Sweden)

    Xueli WU

    2017-08-01

    Full Text Available The risk of the reservoir dam seepage will bring the waste of water resources and the loss of life and property. The ground penetrating radar (GPR is designed as a daily inspection system of dams to improve the existing technology which can't determine the actual situation of the dam seepage tunnel coordinates. The finite difference time domain (FDTD is used to solve the Yee's grids discreatization in two-dimensional space, and its electromagnetic distribution equation is obtained as well. Based on the actual structure of reservoir dam foundation, the ideal model of air layer, concrete layer, clay layer and two water seepage holes is described in detail, and the concrete layer interference model with limestone interference point is established. The system architecture is implemented by using MATLAB, and the forward modeling is performed. The results indicate that ground penetrating radar can be used for deep target detection. Through comparing the detection spectrum of three kinds of frequency electromagnetic wave by changing the center frequency of the GPR electromagnetic wave of 50 MHz, 100 MHz and 200 MHz, it is concluded that the scanning result is more accurate at 100 MHz. At the same time, the simulation results of the interference model show that this method can be used for the detection of complex terrain.

  1. 3-D RESERVOIR AND STOCHASTIC FRACTURE NETWORK MODELING FOR ENHANCED OIL RECOVERY, CIRCLE RIDGE PHOSPHORIA/TENSLEEP RESERVOIR, WIND RIVER RESERVATION, ARAPAHO AND SHOSHONE TRIBES, WYOMING

    Energy Technology Data Exchange (ETDEWEB)

    Paul La Pointe; Jan Hermanson; Robert Parney; Thorsten Eiben; Mike Dunleavy; Ken Steele; John Whitney; Darrell Eubanks; Roger Straub

    2002-11-18

    This report describes the results made in fulfillment of contract DE-FG26-00BC15190, ''3-D Reservoir and Stochastic Fracture Network Modeling for Enhanced Oil Recovery, Circle Ridge Phosphoria/Tensleep Reservoir, Wind River Reservation, Arapaho and Shoshone Tribes, Wyoming''. The goal of this project is to improve the recovery of oil from the Tensleep and Phosphoria Formations in Circle Ridge Oilfield, located on the Wind River Reservation in Wyoming, through an innovative integration of matrix characterization, structural reconstruction, and the characterization of the fracturing in the reservoir through the use of discrete fracture network models. Fields in which natural fractures dominate reservoir permeability, such as the Circle Ridge Field, often experience sub-optimal recovery when recovery processes are designed and implemented that do not take advantage of the fracture systems. For example, a conventional waterflood in a main structural block of the Field was implemented and later suspended due to unattractive results. It is estimated that somewhere less than 20% of the OOIP in the Circle Ridge Field have been recovered after more than 50 years' production. Marathon Oil Company identified the Circle Ridge Field as an attractive candidate for several advanced IOR processes that explicitly take advantage of the natural fracture system. These processes require knowledge of the distribution of matrix porosity, permeability and oil saturations; and understanding of where fracturing is likely to be well-developed or poorly developed; how the fracturing may compartmentalize the reservoir; and how smaller, relatively untested subthrust fault blocks may be connected to the main overthrust block. For this reason, the project focused on improving knowledge of the matrix properties, the fault block architecture and to develop a model that could be used to predict fracture intensity, orientation and fluid flow/connectivity properties. Knowledge

  2. The Aalborg model of teaching in Architecture

    DEFF Research Database (Denmark)

    Knudstrup, Mary-Ann

    2008-01-01

    of academic knowledge means that innovative solutions in building and construction can be realised. This has been expressed by Børge Diderichsen, NOVO, as the following formula: Education + Enterprise = Innovation. At Architecture & Design at Aalborg University, we have been working with sustainable...... environmental architecture. We use a model called the Integrated Design Process, or IDP, which is a hybrid method of designing integrated architecture in an interdisciplinary approach between architecture and engineering. The Integrated Design Process focuses on combining architecture, design, functional...... aspects, energy consumption, indoor environment, and construction in order to achieve a more holistic approach to sustainable environmental architecture. In my presentation I will provide an example of a student project in which this model is applied in practice....

  3. Scale Model Simulation of Enhanced Geothermal Reservoir Creation

    Science.gov (United States)

    Gutierrez, M.; Frash, L.; Hampton, J.

    2012-12-01

    diameter may be drilled into the sample while at reservoir conditions. This allows for simulation of borehole damage as well as injector-producer schemes. Dual 70 MPa syringe pumps set to flow rates between 10 nL/min and 60 mL/min injecting into a partially cased borehole allow for fully contained fracturing treatments. A six sensor acoustic emission (AE) array is used for geometric fracture location estimation during intercept borehole drilling operations. Hydraulic sensors and a thermocouple array allow for additional monitoring and data collection as relevant to computer model validation as well as field test comparisons. The results from preliminary tests inside and outside of the cell demonstrate the functionality of the equipment while also providing some novel data on the propagation and flow characteristics of hydraulic fractures themselves.

  4. A Model-Based Systems Engineering Methodology for Employing Architecture In System Analysis: Developing Simulation Models Using Systems Modeling Language Products to Link Architecture and Analysis

    Science.gov (United States)

    2016-06-01

    ENGINEERING METHODOLOGY FOR EMPLOYING ARCHITECTURE IN SYSTEM ANALYSIS: DEVELOPING SIMULATION MODELS USING SYSTEMS MODELING LANGUAGE PRODUCTS TO LINK... ENGINEERING METHODOLOGY FOR EMPLOYING ARCHITECTURE IN SYSTEM ANALYSIS: DEVELOPING SIMULATION MODELS USING SYSTEMS MODELING LANGUAGE PRODUCTS TO LINK...to model-based systems engineering (MBSE) by formally defining an MBSE methodology for employing architecture in system analysis (MEASA) that presents

  5. Improved storage efficiency through geologic modeling and reservoir simulation

    Energy Technology Data Exchange (ETDEWEB)

    Ammer, J.R.; Mroz, T.H.; Covatch, G.L.

    1997-11-01

    The US Department of Energy (DOE), through partnerships with industry, is demonstrating the importance of geologic modeling and reservoir simulation for optimizing the development and operation of gas storage fields. The geologic modeling and reservoir simulation study for the Natural Fuel Gas Supply Corporation CRADA was completed in September 1995. The results of this study were presented at the 1995 Society of Petroleum Engineers` (SPE) Eastern Regional Meeting. Although there has been no field verification of the modeling results, the study has shown the potential advantages and cost savings opportunities of using horizontal wells for storage enhancement. The geologic modeling for the Equitrans` CRADA was completed in September 1995 and was also presented at the 1995 SPE Eastern Regional Meeting. The reservoir modeling of past field performance was completed in November 1996 and prediction runs are currently being made to investigate the potential of offering either a 10 day or 30 day peaking service in addition to the existing 110 day base load service. Initial results have shown that peaking services can be provided through remediation of well damage and by drilling either several new vertical wells or one new horizontal well. The geologic modeling for the Northern Indiana Public Service Company CRADA was completed in November 1996 with a horizontal well being completed in January 1997. Based on well test results, the well will significantly enhance gas deliverability from the field and will allow the utilization of gas from an area of the storage field that was not accessible from their existing vertical wells. Results are presented from these three case studies.

  6. Security Model For Service-Oriented Architecture

    CERN Document Server

    Karimi, Oldooz

    2011-01-01

    In this article, we examine how security applies to Service Oriented Architecture (SOA). Before we discuss security for SOA, lets take a step back and examine what SOA is. SOA is an architectural approach which involves applications being exposed as "services". Originally, services in SOA were associated with a stack of technologies which included SOAP, WSDL, and UDDI. This article addresses the defects of traditional enterprise application integration by combining service oriented-architecture and web service technology. Application integration is then simplified to development and integration of services to tackle connectivity of isomerous enterprise application integration, security, loose coupling between systems and process refactoring and optimization.

  7. Modelling sediment export, retention and reservoir sedimentation in drylands with the WASA-SED model

    Directory of Open Access Journals (Sweden)

    E. N. Mueller

    2010-04-01

    Full Text Available Current soil erosion and reservoir sedimentation modelling at the meso-scale is still faced with intrinsic problems with regard to open scaling questions, data demand, computational efficiency and deficient implementations of retention and re-mobilisation processes for the river and reservoir networks. To overcome some limitations of current modelling approaches, the semi-process-based, spatially semi-distributed modelling framework WASA-SED (Vers. 1 was developed for water and sediment transport in large dryland catchments. The WASA-SED model simulates the runoff and erosion processes at the hillslope scale, the transport and retention processes of suspended and bedload fluxes in the river reaches and the retention and remobilisation processes of sediments in reservoirs. The modelling tool enables the evaluation of management options both for sustainable land-use change scenarios to reduce erosion in the headwater catchments as well as adequate reservoir management options to lessen sedimentation in large reservoirs and reservoir networks. The model concept, its spatial discretisation scheme and the numerical components of the hillslope, river and reservoir processes are described and a model application for the meso-scale dryland catchment Isábena in the Spanish Pre-Pyrenees (445 km2 is presented to demonstrate the capabilities, strengths and limits of the model framework. The example application showed that the model was able to reproduce runoff and sediment transport dynamics of highly erodible headwater badlands, the transient storage of sediments in the dryland river system, the bed elevation changes of the 93 hm3 Barasona reservoir due to sedimentation as well as the life expectancy of the reservoir under different management options.

  8. THMC Modeling of EGS Reservoirs -- Continuum through Discontinuum Representations. Capturing Reservoir Stimulation, Evolution and Induced Seismicity

    Energy Technology Data Exchange (ETDEWEB)

    Elsworth, Derek [Pennsylvania State Univ., State College, PA (United States); Izadi, Ghazal [Pennsylvania State Univ., State College, PA (United States); Gan, Quan [Pennsylvania State Univ., State College, PA (United States); Fang, Yi [Pennsylvania State Univ., State College, PA (United States); Taron, Josh [US Geological Survey, Menlo Park, CA (United States); Sonnenthal, Eric [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-07-28

    This work has investigated the roles of effective stress induced by changes in fluid pressure, temperature and chemistry in contributing to the evolution of permeability and induced seismicity in geothermal reservoirs. This work has developed continuum models [1] to represent the progress or seismicity during both stimulation [2] and production [3]. These methods have been used to resolve anomalous observations of induced seismicity at the Newberry Volcano demonstration project [4] through the application of modeling and experimentation. Later work then focuses on the occurrence of late stage seismicity induced by thermal stresses [5] including the codifying of the timing and severity of such responses [6]. Furthermore, mechanistic linkages between observed seismicity and the evolution of permeability have been developed using data from the Newberry project [7] and benchmarked against field injection experiments. Finally, discontinuum models [8] incorporating the roles of discrete fracture networks have been applied to represent stimulation and then thermal recovery for new arrangements of geothermal wells incorporating the development of flow manifolds [9] in order to increase thermal output and longevity in EGS systems.

  9. Two-phase relative permeability models in reservoir engineering calculations

    Energy Technology Data Exchange (ETDEWEB)

    Siddiqui, S.; Hicks, P.J.; Ertekin, T.

    1999-01-15

    A comparison of ten two-phase relative permeability models is conducted using experimental, semianalytical and numerical approaches. Model predicted relative permeabilities are compared with data from 12 steady-state experiments on Berea and Brown sandstones using combinations of three white mineral oils and 2% CaCl1 brine. The model results are compared against the experimental data using three different criteria. The models are found to predict the relative permeability to oil, relative permeability to water and fractional flow of water with varying degrees of success. Relative permeability data from four of the experimental runs are used to predict the displacement performance under Buckley-Leverett conditions and the results are compared against those predicted by the models. Finally, waterflooding performances predicted by the models are analyzed at three different viscosity ratios using a two-dimensional, two-phase numerical reservoir simulator. (author)

  10. Model-driven evolution of software architectures

    OpenAIRE

    Graaf, B.S.

    2007-01-01

    Software evolves continuously. As a consequence, software systems tend to become increasingly complex and, as such, more difficult to change. A software system's complexity is for a large part determined by its structure, or architecture. In this thesis we investigate how to reduce the risks and costs associated with the evolution of software architectures. Automation and abstraction are two basic software engineering techniques to deal with complexity. In this thesis we investigate the appli...

  11. Architecture design in global and model-centric software development

    NARCIS (Netherlands)

    Heijstek, Werner

    2012-01-01

    This doctoral dissertation describes a series of empirical investigations into representation, dissemination and coordination of software architecture design in the context of global software development. A particular focus is placed on model-centric and model-driven software development.

  12. Architecture design in global and model-centric software development

    NARCIS (Netherlands)

    Heijstek, Werner

    2012-01-01

    This doctoral dissertation describes a series of empirical investigations into representation, dissemination and coordination of software architecture design in the context of global software development. A particular focus is placed on model-centric and model-driven software development.

  13. Research on system architecture of modeling and simulation

    Institute of Scientific and Technical Information of China (English)

    WANG Jiangyun; WANG Xingren

    2007-01-01

    The modeling and simulation(M&S)architecture describes and defines the relationship between the difeerent parts of a simulation.The simulation system architecture and simulation support platform architecture are discussed separately.The simulation support platform architecture consists of the management layer,the resource layer,the communication layer,the application layer and the infrastructure layer.The best Wav is to design and realize the M&S collaborative environment for simulation support platform in the resource-communication-application three-dimension space.

  14. The influence of geological data on the reservoir modelling and history matching process

    NARCIS (Netherlands)

    De Jager, G.

    2012-01-01

    For efficient production of hydrocarbons from subsurface reservoirs it is important to understand the spatial properties of the reservoir. As there is almost always too little information on the reservoir to build a representative model directly, other techniques have been developed for generating r

  15. Towards an integrated workflow for structural reservoir model updating and history matching

    NARCIS (Netherlands)

    Leeuwenburgh, O.; Peters, E.; Wilschut, F.

    2011-01-01

    A history matching workflow, as typically used for updating of petrophysical reservoir model properties, is modified to include structural parameters including the top reservoir and several fault properties: position, slope, throw and transmissibility. A simple 2D synthetic oil reservoir produced by

  16. Towards an integrated workflow for structural reservoir model updating and history matching

    NARCIS (Netherlands)

    Leeuwenburgh, O.; Peters, E.; Wilschut, F.

    2011-01-01

    A history matching workflow, as typically used for updating of petrophysical reservoir model properties, is modified to include structural parameters including the top reservoir and several fault properties: position, slope, throw and transmissibility. A simple 2D synthetic oil reservoir produced by

  17. Advanced quality prediction model for software architectural knowledge sharing

    NARCIS (Netherlands)

    Liang, Peng; Jansen, Anton; Avgeriou, Paris; Tang, Antony; Xu, Lai

    2011-01-01

    In the field of software architecture, a paradigm shift is occurring from describing the outcome of architecting process to describing the Architectural Knowledge (AK) created and used during architecting. Many AK models have been defined to represent domain concepts and their relationships, and the

  18. A Concept Transformation Learning Model for Architectural Design Learning Process

    Science.gov (United States)

    Wu, Yun-Wu; Weng, Kuo-Hua; Young, Li-Ming

    2016-01-01

    Generally, in the foundation course of architectural design, much emphasis is placed on teaching of the basic design skills without focusing on teaching students to apply the basic design concepts in their architectural designs or promoting students' own creativity. Therefore, this study aims to propose a concept transformation learning model to…

  19. Model-based safety architecture framework for complex systems

    NARCIS (Netherlands)

    Schuitemaker, K.; Rajabalinejad, M.; Braakhuis, J.G.; Podofilini, Luca; Sudret, Bruno; Stojadinovic, Bozidar; Zio, Enrico; Kröger, Wolfgang

    2015-01-01

    The shift to transparency and rising need of the general public for safety, together with the increasing complexity and interdisciplinarity of modern safety-critical Systems of Systems (SoS) have resulted in a Model-Based Safety Architecture Framework (MBSAF) for capturing and sharing architectural

  20. A Concept Transformation Learning Model for Architectural Design Learning Process

    Science.gov (United States)

    Wu, Yun-Wu; Weng, Kuo-Hua; Young, Li-Ming

    2016-01-01

    Generally, in the foundation course of architectural design, much emphasis is placed on teaching of the basic design skills without focusing on teaching students to apply the basic design concepts in their architectural designs or promoting students' own creativity. Therefore, this study aims to propose a concept transformation learning model to…

  1. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2003-09-25

    The University of Alabama in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company are undertaking an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling that utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary objective of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. The principal research effort for Year 3 of the project has been reservoir characterization, 3-D modeling, testing of the geologic-engineering model, and technology transfer. This effort has included six tasks: (1) the study of seismic attributes, (2) petrophysical characterization, (3) data integration, (4) the building of the geologic-engineering model, (5) the testing of the geologic-engineering model and (6) technology transfer. This work was scheduled for completion in Year 3. Progress on the project is as follows: geoscientific reservoir characterization is completed. The architecture, porosity types and heterogeneity of the reef and shoal reservoirs at Appleton and Vocation Fields have been characterized using geological and geophysical data. The study of rock-fluid interactions has been completed. Observations regarding the diagenetic

  2. xpMODEL: A Novel Model for ASIP Architecture

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    With greater flexibility and less cost, there is a trend that application specific instruction set processor (ASIP) will become the alternative implementation style to application of specific integrated circuit (ASIC). Architecture model is a key component in ASIP design flow. A novel ASIP model, xpMODEL, was presented. Its key features include: explicit specification of the memory subsystem allowing novel memory organizations and hierarchies; the introduction of meta-operator and instruction behavior extended finite state machine providing xpMODEL with ability to model execution sequencing, inherent parallelism, data/control/structural hazards, and out-oforder execution mode in ASIP. A comparison with other ASIP models shows the superiority of xpMODEL.

  3. An analytical thermohydraulic model for discretely fractured geothermal reservoirs

    Science.gov (United States)

    Fox, Don B.; Koch, Donald L.; Tester, Jefferson W.

    2016-09-01

    In discretely fractured reservoirs such as those found in Enhanced/Engineered Geothermal Systems (EGS), knowledge of the fracture network is important in understanding the thermal hydraulics, i.e., how the fluid flows and the resulting temporal evolution of the subsurface temperature. The purpose of this study was to develop an analytical model of the fluid flow and heat transport in a discretely fractured network that can be used for a wide range of modeling applications and serve as an alternative analysis tool to more computationally intensive numerical codes. Given the connectivity and structure of a fracture network, the flow in the system was solved using a linear system of algebraic equations for the pressure at the nodes of the network. With the flow determined, the temperature in the fracture was solved by coupling convective heat transport in the fracture with one-dimensional heat conduction perpendicular to the fracture, employing the Green's function derived solution for a single discrete fracture. The predicted temperatures along the fracture surfaces from the analytical solution were compared to numerical simulations using the TOUGH2 reservoir code. Through two case studies, we showed the capabilities of the analytical model and explored the effect of uncertainty in the fracture apertures and network structure on thermal performance. While both sources of uncertainty independently produce large variations in production temperature, uncertainty in the network structure, whenever present, had a predominant influence on thermal performance.

  4. Proactive Modeling of Market, Product and Production Architectures

    DEFF Research Database (Denmark)

    Mortensen, Niels Henrik; Hansen, Christian Lindschou; Hvam, Lars

    2011-01-01

    This paper presents an operational model that allows description of market, products and production architectures. The main feature of this model is the ability to describe both structural and functional aspect of architectures. The structural aspect is an answer to the question: What constitutes...... the architecture, e.g. standard designs, design units and interfaces? The functional aspect is an answer to the question: What is the behaviour or the architecture, what is it able to do, i.e. which products at which performance levels can be derived from the architecture? Among the most important benefits......: Improved preparedness for future launches, e.g. user interface and improved energy efficiency Achievement of attractive cost- and technical performance level on all products in the product family On time launch of the first generation of the product family"...

  5. Integration of geology and reservoir engineering to produce reservoir simulation model at Cabin Creek Field, Cedar Creek Anticline, Montana

    Energy Technology Data Exchange (ETDEWEB)

    Pieterson, R.; DiMarco, M.J.; Sodersten, S.S. [Shell Western E& P Inc., Houston, TX (United States)

    1996-12-31

    Because of its mature stage of development, a key aspect of continued economic development of the Cedar Creek Anticline (CCA), Montana (STOOIP > 2 billion barrels with over 360 MMstb produced) is the Identification of remaining pods of high S{sub o} within the original field boundaries. Present economic conditions make it essential to select drillsites with high probabilities of success and high prognoses flow rates in these remaking high S. area. Integration of a well-constrained geologic model and reservoir simulation pinpointed remaining pods of oil in a 3-m thick, subvertically fractured, dolomitic limestone reservoir of the Carboniferous Mission Canyon Formation in the Cabin Creek Field of the CCA This resulted in a successful high-flow-rate horizontal well (initial rate >800 BOPD) whose oil production was accurately predicted by a 3-D reservoir simulation. The model has 53,750 gridblocks each of which Is 60 by 60 m. The effect of the natural-fracture network was constrained with the k{sub v}/k{sub h} (vertical to horizontal permeability ratio). The simulation covered a 40-yr. production period. Gross production was Input as a constraint; oil and water rates were matched. Adjustments to absolute permeability, aquifer volume and relative water permeability were required to obtain a match between observed and simulated production rates. The model was fine tuned by matching the production of individual wells in areas with a high remaining S{sub o}. This project demonstrated that (1) interplay of geology and reservoir engineering provided a better reservoir model than could have been done individually, (2) simulation work identified horizontal drilling and recompletion candidates, with one successful horizontal well completed to date, and (3) use of the reservoir simulator for field-scale modeling In conjunction with a well-refined geologic synthesis can successfully pinpoint undeveloped reserves at CCA.

  6. Integration of geology and reservoir engineering to produce reservoir simulation model at Cabin Creek Field, Cedar Creek Anticline, Montana

    Energy Technology Data Exchange (ETDEWEB)

    Pieterson, R.; DiMarco, M.J.; Sodersten, S.S. (Shell Western E P Inc., Houston, TX (United States))

    1996-01-01

    Because of its mature stage of development, a key aspect of continued economic development of the Cedar Creek Anticline (CCA), Montana (STOOIP > 2 billion barrels with over 360 MMstb produced) is the Identification of remaining pods of high S[sub o] within the original field boundaries. Present economic conditions make it essential to select drillsites with high probabilities of success and high prognoses flow rates in these remaking high S. area. Integration of a well-constrained geologic model and reservoir simulation pinpointed remaining pods of oil in a 3-m thick, subvertically fractured, dolomitic limestone reservoir of the Carboniferous Mission Canyon Formation in the Cabin Creek Field of the CCA This resulted in a successful high-flow-rate horizontal well (initial rate >800 BOPD) whose oil production was accurately predicted by a 3-D reservoir simulation. The model has 53,750 gridblocks each of which Is 60 by 60 m. The effect of the natural-fracture network was constrained with the k[sub v]/k[sub h] (vertical to horizontal permeability ratio). The simulation covered a 40-yr. production period. Gross production was Input as a constraint; oil and water rates were matched. Adjustments to absolute permeability, aquifer volume and relative water permeability were required to obtain a match between observed and simulated production rates. The model was fine tuned by matching the production of individual wells in areas with a high remaining S[sub o]. This project demonstrated that (1) interplay of geology and reservoir engineering provided a better reservoir model than could have been done individually, (2) simulation work identified horizontal drilling and recompletion candidates, with one successful horizontal well completed to date, and (3) use of the reservoir simulator for field-scale modeling In conjunction with a well-refined geologic synthesis can successfully pinpoint undeveloped reserves at CCA.

  7. Multicore technology architecture, reconfiguration, and modeling

    CERN Document Server

    Qadri, Muhammad Yasir

    2013-01-01

    The saturation of design complexity and clock frequencies for single-core processors has resulted in the emergence of multicore architectures as an alternative design paradigm. Nowadays, multicore/multithreaded computing systems are not only a de-facto standard for high-end applications, they are also gaining popularity in the field of embedded computing. The start of the multicore era has altered the concepts relating to almost all of the areas of computer architecture design, including core design, memory management, thread scheduling, application support, inter-processor communication, debu

  8. Reconstruction of Existing Reservoir Model for Its Calibration to Dynamic Data

    Science.gov (United States)

    Le Ravalec-Dupin, M.; Hu, L. Y.; Roggero, F.

    The increase in computer power and the recent developments in history-matching can motivate the reexamination of previously built reservoir models. To save the time of engineers and the CPU time, four distinct algorithms, which allow for rebuilding an existing reservoir model without restarting the reservoir study from scratch, were formulated. The algorithms involve techniques such as optimization, relaxation, Wiener filtering, or sequential reconstruction. They are used to identify a stochastic function and a set of random numbers. Given the stochastic function, the random numbers yield a realization that is close to the existing reservoir model. Once the random numbers are known, the existing reservoir model can be submitted to a new history-matching process to improve the data fit or to account for newly collected data. A practical implementation is presented within the context of facies reservoirs. This article focuses on a previously built facies reservoir model. Although the simulation procedure is unknown to the authors, a set of random numbers are identified so that when provided to a multiple-point statistics simulator, a realization very close to the existing reservoir model is obtained. A new history-matching procedure is then run to update the existing reservoir model and to integrate the fractional flow rates measured in two producing wells drilled after the building of the existing reservoir model.

  9. Developing the aquatic-coupled reservoir model to simulate carbon dioxide emission from a young boreal hydroelectric reservoir

    Science.gov (United States)

    Kim, Y.; Roulet, N. T.; Strachan, I. B.; Tremblay, A.

    2013-12-01

    We developed a process-based biogeochemical reservoir model, called AF-DNDC (Aquatic-coupled Forest-DNDC), to project carbon (C) flux from water surface of a recently created hydro-electric reservoir that flooded a boreal landscape. The basis of the reservoir model is Forest-DNDC, a biogeochemical model for C and nitrogen cycling in forests and wetlands. AF-DNDC was developed by coupling a lake C model to a flooded version of Forest-DNDC. AF-DNDC includes the C cycling through the aquatic carbon pools, such as DIC (dissolved inorganic C), DOC (dissolved organic C), and planktonic community as well as C exchange between air, water, and sediment. AF-DNDC was used to examine the net change in carbon dioxide (CO2) exchange between the surface and the atmosphere over the first seven years post flooding of the Eastmain-1 reservoir in northern Quebec. With present day climate and environmental conditions, simulated daily CO2 emissions from the flooded forest averaged 1.69 g C m-2 d-1 (range 0 to 20.49), and from the flooded peatland averaged 0.87 g C m-2 d-1 (range 0 to 6.86). Simulated CO2 emissions decreased with the age of reservoir. They were larger than eddy-covariance measured CO2 fluxes from the water surface over flooded forests, but compared well to the eddy-covariance fluxes during the open-water period. The simulated emissions were significantly correlated with the measured fluxes from the flooded forest (r2 = 0.33; p < 0.01) and flooded peatland (r2 = 0.41; p < 0.01). The patterns over the year were similar. AF-DNDC is suitable for use to assess the major changes in CO2 exchange due to the creation of reservoirs in boreal regions.

  10. Investigation of seasonal thermal flow in a real dam reservoir using 3-D numerical modeling

    Directory of Open Access Journals (Sweden)

    Üneş Fatih

    2015-03-01

    Full Text Available Investigations indicate that correct estimation of seasonal thermal stratification in a dam reservoir is very important for the dam reservoir water quality modeling and water management problems. The main aim of this study is to develop a hydrodynamics model of an actual dam reservoir in three dimensions for simulating a real dam reservoir flows for different seasons. The model is developed using nonlinear and unsteady continuity, momentum, energy and k-ε turbulence model equations. In order to include the Coriolis force effect on the flow in a dam reservoir, Coriolis force parameter is also added the model equations. Those equations are constructed using actual dimensions, shape, boundary and initial conditions of the dam and reservoir. Temperature profiles and flow visualizations are used to evaluate flow conditions in the reservoir. Reservoir flow’s process and parameters are determined all over the reservoir. The mathematical model developed is capable of simulating the flow and thermal characteristics of the reservoir system for seasonal heat exchanges. Model simulations results obtained are compared with field measurements obtained from gauging stations for flows in different seasons. The results show a good agreement with the field measurements.

  11. Model-driven evolution of software architectures

    NARCIS (Netherlands)

    Graaf, B.S.

    2007-01-01

    Software evolves continuously. As a consequence, software systems tend to become increasingly complex and, as such, more difficult to change. A software system's complexity is for a large part determined by its structure, or architecture. In this thesis we investigate how to reduce the risks and cos

  12. Facies architecture of the Bluejacket Sandstone in the Eufaula Lake area, Oklahoma: Implications for the reservoir characterization of the Bartlesville Sandstone

    Energy Technology Data Exchange (ETDEWEB)

    Ye, Liangmiao; Yang, Kexian [Univ. of Tulsa, OK (United States)

    1997-08-01

    Outcrop studies of the Bluejacket Sandstone (Middle Pennsylvanian) provide significant insights to reservoir architecture of the subsurface equivalent Bartlesville Sandstone. Quarry walls and road cuts in the Lake Eufaula area offer excellent exposures for detailed facies architectural investigations using high-precision surveying, photo mosaics. Directional minipermeameter measurements are being conducted. Subsurface studies include conventional logs, borehole image log, and core data. Reservoir architectures are reconstructed in four hierarchical levels: multi-storey sandstone, i.e. discrete genetic intervals; individual discrete genetic interval; facies within a discrete genetic interval; and lateral accretion bar deposits. In both outcrop and subsurface, the Bluejacket (Bartlesville) Sandstone comprises two distinctive architectures: a lower braided fluvial and an upper meandering fluvial. Braided fluvial deposits are typically 30 to 80 ft thick, and are laterally persistent filling an incised valley wider than the largest producing fields. The lower contact is irregular with local relief of 50 ft. The braided-fluvial deposits consist of 100-400-ft wide, 5-15-ft thick channel-fill elements. Each channel-fill interval is limited laterally by an erosional contact or overbank deposits, and is separated vertically by discontinuous mudstones or highly concentrated mudstone interclast lag conglomerates. Low-angle parallel-stratified or trough cross-stratified medium- to coarse-grained sandstones volumetrically dominate. This section has a blocky well log profile. Meandering fluvial deposits are typically 100 to 150 ft thick and comprise multiple discrete genetic intervals.

  13. Control architecture of power systems: Modeling of purpose and function

    DEFF Research Database (Denmark)

    Heussen, Kai; Saleem, Arshad; Lind, Morten

    2009-01-01

    for semantically consistent modeling of control architecture is presented. The method, called Multilevel Flow Modeling (MFM), is applied to the case of system balancing. It was found that MFM is capable of capturing implicit control knowledge, which is otherwise difficult to formalize. The method has possible...... of power systems and it is necessary to identify requirements and functions. How does new control architecture fit with the old architecture? How can power system functions be specified independent of technology? What is the purpose of control in power systems? In this paper, a method suitable...

  14. Model Refinement in the Model Driven Architecture Context

    Directory of Open Access Journals (Sweden)

    Paulo Cezar Stadzisz

    2012-01-01

    Full Text Available Problem statement: Model Driven Architecture (MDA is a software development approach based on the design and the transformation of models. In MDA, models are systematically translated to other models and to a source code. Model transformation plays a key role in MDA. Several model transformation languages have been launched lately, aiming to facilitate the translation of input models to output models. The employment of such languages in practical contexts has succeed, although quite often those languages cannot be directly applied to a particular type of model transformation, called refinement. Approach: This study provides a general overview on model refinement and investigates two approaches for model refinement based on Atlas Transformation Language (ATL referred to as: Refining mode and module superimposition. ATL is a widely adopted language for solving model transformation problems in the MDA approach. Results: This study presents the comparative results obtained from the analysis of the Refining Mode and the Module Superimposition approaches, emphasizing their application benefits. Conclusion: The increasing use of MDA for the design of software systems empowered researches on how developers may benefit from approaches that perform model refinement. The main advantages achieved with the use of the Module Superimposition technique are maintainability and reusability improvement, obtained through module composition and rule superimposition. In its turn, the Refining Mode stands out for its ease of use.

  15. THE MODELING TEMPLATE OF ENTERPRISE ARCHITECTURE OF PUBLIC CATERING

    Directory of Open Access Journals (Sweden)

    Baranovskaya T. P.

    2016-02-01

    Full Text Available The article presents results of developing the template architecture for an enterprise of public catering. As a prototype for the template, we have selected the restaurant called Phoenix. The development pattern of architecture was based on the typical features of public catering establishments described in the business model. The main results of the study are: generalized business model, built on the method developed by A. Osterwalder, graphical layout of business processes, implemented in the tool environment, All Fusion Process Modeler (BPWin and developed models of decomposition of business processes, model business event, the location of the model functions, integration model, models, data architecture, class diagram, application portfolio and technology infrastructure. The architecture of a company of public catering may serve as a template for other businesses whose business model matches the business model of the research object. We have developed a tree of objectives and functions, the model of the enterprise, the data architecture, technology infrastructure and application portfolio are typical for the industry. The results of the study have practical value and can be used by the industry as at the design stage and improvement

  16. Markov random fields simulation: an introduction to the stochastic modelling of petroleum reservoirs; Simulacao de campos aleatorios markovianos: uma introducao voltada a modelagem estocastica de reservatorios de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Saldanha Filho, Paulo Carlos

    1998-02-01

    Stochastic simulation has been employed in petroleum reservoir characterization as a modeling tool able to reconcile information from several different sources. It has the ability to preserve the variability of the modeled phenomena and permits transference of geological knowledge to numerical models of flux, whose predictions on reservoir constitute the main basis for reservoir management decisions. Several stochastic models have been used and/or suggested, depending on the nature of the phenomena to be described. Markov Random Fields (MRFs) appear as an alternative for the modeling of discrete variables, mainly reservoirs with mosaic architecture of facies. In this dissertation, the reader is introduced to the stochastic modeling by MRFs in a generic sense. The main aspects of the technique are reviewed. MRF Conceptual Background is described: its characterization through the Markovian property and the equivalence to Gibbs distributions. The framework for generic modeling of MRFs is described. The classical models of Ising and Potts-Strauss are specific in this context and are related to models of Ising and Potts-Strauss are specific in this context and are related to models used in petroleum reservoir characterization. The problem of parameter estimation is discussed. The maximum pseudolikelihood estimators for some models are presented. Estimators for two models useful for reservoir characterization are developed, and represent a new contribution to the subject. Five algorithms for the Conditional Simulation of MRFs are described: the Metropolis algorithm, the algorithm of German and German (Gibbs sampler), the algorithm of Swendsen-Wang, the algorithm of Wolff, and the algorithm of Flinn. Finally, examples of simulation for some of the models discussed are presented, along with their implications on the modelling of petroleum reservoirs. (author)

  17. Architecture on Architecture

    DEFF Research Database (Denmark)

    Olesen, Karen

    2016-01-01

    This paper will discuss the challenges faced by architectural education today. It takes as its starting point the double commitment of any school of architecture: on the one hand the task of preserving the particular knowledge that belongs to the discipline of architecture, and on the other hand...... that is not scientific or academic but is more like a latent body of data that we find embedded in existing works of architecture. This information, it is argued, is not limited by the historical context of the work. It can be thought of as a virtual capacity – a reservoir of spatial configurations that can...... the autonomy of architecture, not as an esoteric concept but as a valid source of information in a pragmatic design practice, may help us overcome the often-proclaimed dichotomy between formal autonomy and a societally committed architecture. It follows that in architectural education there can be a close...

  18. ARCHITECTURAL LARGE CONSTRUCTED ENVIRONMENT. MODELING AND INTERACTION USING DYNAMIC SIMULATIONS

    Directory of Open Access Journals (Sweden)

    P. Fiamma

    2012-09-01

    Full Text Available How to use for the architectural design, the simulation coming from a large size data model? The topic is related to the phase coming usually after the acquisition of the data, during the construction of the model and especially after, when designers must have an interaction with the simulation, in order to develop and verify their idea. In the case of study, the concept of interaction includes the concept of real time "flows". The work develops contents and results that can be part of the large debate about the current connection between "architecture" and "movement". The focus of the work, is to realize a collaborative and participative virtual environment on which different specialist actors, client and final users can share knowledge, targets and constraints to better gain the aimed result. The goal is to have used a dynamic micro simulation digital resource that allows all the actors to explore the model in powerful and realistic way and to have a new type of interaction in a complex architectural scenario. On the one hand, the work represents a base of knowledge that can be implemented more and more; on the other hand the work represents a dealt to understand the large constructed architecture simulation as a way of life, a way of being in time and space. The architectural design before, and the architectural fact after, both happen in a sort of "Spatial Analysis System". The way is open to offer to this "system", knowledge and theories, that can support architectural design work for every application and scale. We think that the presented work represents a dealt to understand the large constructed architecture simulation as a way of life, a way of being in time and space. Architecture like a spatial configuration, that can be reconfigurable too through designing.

  19. Performance Prediction of Two-Phase Geothermal Reservoir using Lumped Parameter Model

    Science.gov (United States)

    Nurlaela, F.; Sutopo

    2016-09-01

    Many studies have been conducted to simulate performance of low-temperature geothermal reservoirs using lumped parameter method. Limited work had been done on applying non-isothermal lumped parameter models to higher temperature geothermal reservoirs. In this study, the lumped parameter method was applied to high-temperature two phase geothermal reservoirs. The model couples both energy and mass balance equations thus can predict temperature, pressure and fluid saturation changes in the reservoir as a result of production, reinjection of water, and/or natural recharge. This method was validated using reservoir simulation results of TOUGH2. As the results, the two phase lumped parameter model simulation without recharge shows good matching, however reservoir model with recharge condition show quite good conformity.

  20. Application of Seismic Data to Reservoir Modeling of the Chegu 201 Block

    Institute of Scientific and Technical Information of China (English)

    CaiYi; ZhangXiangzhong; ZhangXinshang

    2005-01-01

    Great uncertainty exists in reservoir models built for blocks where well spacing is uneven or large. The uncertainty in reservoir models can be significantly reduced by using Coordinate Cokriging Sequential Gaussian Simulation technology, in combination with the restriction of seismic characteristic data. Satisfactory reservoir parameter interpolation results, which are more accurate than those derived only from borehole data, are obtained, giving rise to a reasonable combination of widespread and dense-sampled seismic (soft data) data with borehole data (hard data). A significant effect has been made in reservoir parameter modeling in the Chegu 201 block of the Futai Oilfield by using this technology.

  1. Integrated methodology for constructing a quantified hydrodynamic model for application to clastic petroleum reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Honarpour, M. M.; Schatzinger, R. A.; Szpakiewicz, M. J.; Jackson, S. R.; Sharma, B.; Tomutsa, L.; Chang, M. M.

    1990-01-01

    A comprehensive, multidisciplinary, stepwise methodology is developed for constructing and integration geological and engineering information for predicting petroleum reservoir performance. This methodology is based on our experience in characterizing shallow marine reservoirs, but it should also apply to other deposystems. The methodology is presented as Part 1 of this report. Three major tasks that must be studied to facilitate a systematic approach for constructing a predictive hydrodynamic model for petroleum reservoirs are addressed: (1) data collection, organization, evaluation, and integration; (2) hydrodynamic model construction and verification; and (3) prediction and ranking of reservoir parameters by numerical simulation using data derived from the model. 39 refs., 62 figs., 13 tabs.

  2. Anisotropic rock physics models for interpreting pore structures in carbonate reservoirs

    Institute of Scientific and Technical Information of China (English)

    Li Sheng-Jie; Shao Yu; Chen Xu-Qiang

    2016-01-01

    We developed an anisotropic effective theoretical model for modeling the elastic behavior of anisotropic carbonate reservoirs by combining the anisotropic self-consistent approximation and differential effective medium models. By analyzing the measured data from carbonate samples in the TL area, a carbonate pore-structure model for estimating the elastic parameters of carbonate rocks is proposed, which is a prerequisite in the analysis of carbonate reservoirs. A workfl ow for determining elastic properties of carbonate reservoirs is established in terms of the anisotropic effective theoretical model and the pore-structure model. We performed numerical experiments and compared the theoretical prediction and measured data. The result of the comparison suggests that the proposed anisotropic effective theoretical model can account for the relation between velocity and porosity in carbonate reservoirs. The model forms the basis for developing new tools for predicting and evaluating the properties of carbonate reservoirs.%♦Corresponding author: Li Sheng-Jie (Email: Richard@cup.edu.cn)

  3. Fractured-basement reservoir modeling using continuous fracture modeling (CFM) method

    Science.gov (United States)

    Isniarny, Nadya; Haris, Abdul; Nurdin, Safrizal

    2016-02-01

    The challenge in oil and gas exploration has now shifted due to increasingly difficult to get back up economic value in a conventional reservoir. Explorationist are developing various drilling technology, optimizing conventional reserves and unconventional reserve in reservoirs. One of the unconventional reservoir that has been developed is the basement reservoir. This rock type has no primary porosity and the permeability of the rocks of this type are generally influenced by the naturally fracture networks. The purpose of this study is to map the fracture intensity distribution in the basement reservoir using Continuous Fracture Modeling (CFM) method. CFM method applies the basic concepts of neural network in finding a relationship between well data with seismic data in order to build a model of fracture intensity. The Formation Micro Imager (FMI) interpretation data is used to identify the presence of fracture along the well as dip angle and dip azimuth. This indicator will be laterally populated in 3D grid model. Several seismic attribute which are generated from seismic data is used as a guidance to populate fracture intensity in the model. The results from the model were validated with Drill Stem Test (DST) data. Zones of high fracture intensity on the model correlates positively with the presence of fluid in accordance with DST data.

  4. Supporting crosscutting concern modelling in software architecture design

    Institute of Scientific and Technical Information of China (English)

    CAO Donggang; MEI Hong; ZHOU Minghui

    2007-01-01

    Crosscutting concerns such as logging,security,and transaction,are well supported in the programming level by aspect-oriented programming technologies.However,addressing these issues in the high-level architecture design still remains open.This paper presents a novel approach to supporting crosscutting concern modelling in the software architecture design of component-based systems.We introduce a new element named "Aspect"into our architecture description language,ABC/ADL,to clearly model the behavior of crosscutting concerns.Aspect is the first class entity as Component and Connector in ABC/ADL.ABC/ADL Connectors provide the weaving points where the component and aspect crosscut.This approach effectively enables "separation of concerns" in high-level architecture design,and facilitates black-box reuse of COTS components.

  5. A new model for designing uncertain enterprise architecture

    Directory of Open Access Journals (Sweden)

    Jamshid Afshani

    2012-04-01

    Full Text Available C4ISR framework describes architecture in three views of information architecture and defines a set of products, which are main outputs of enterprise architecture design. Formats and templates, which are presented for C4ISR products, cannot describe uncertainty in process or data. Meanwhile, uncertainty in many information systems is unavoidable and using the concept of fuzzy numbers in architecture design helps architects handle uncertainty in process and data of organization. In this paper, we present a new template based on fuzzy-UML concept for some of C4ISR products such as Logical Data Model (OV-7, Operational Event/Trace Description (OV-6c and Systems Event/Trace Description (SV-10c. To explain further, fictional Fast Pass system used at OilCo gas stations is used to demonstrate details of our proposed model.

  6. Formalism Challenges of the Cougaar Model Driven Architecture

    Science.gov (United States)

    Bohner, Shawn A.; George, Boby; Gracanin, Denis; Hinchey, Michael G.

    2004-01-01

    The Cognitive Agent Architecture (Cougaar) is one of the most sophisticated distributed agent architectures developed today. As part of its research and evolution, Cougaar is being studied for application to large, logistics-based applications for the Department of Defense (DoD). Anticipiting future complex applications of Cougaar, we are investigating the Model Driven Architecture (MDA) approach to understand how effective it would be for increasing productivity in Cougar-based development efforts. Recognizing the sophistication of the Cougaar development environment and the limitations of transformation technologies for agents, we have systematically developed an approach that combines component assembly in the large and transformation in the small. This paper describes some of the key elements that went into the Cougaar Model Driven Architecture approach and the characteristics that drove the approach.

  7. Determining between-well reservoir architecture in deltaic sandstones using only well data: Oligocene Frio formation, Tijerina-Canales-Blucher field, South Texas

    Energy Technology Data Exchange (ETDEWEB)

    Knox, P.R. [Univ. of Texas, Austin, TX (United States)

    1996-09-01

    Accurate prediction of compartment architecture and intra-compartment heterogeneity is necessary to locate and recover the estimated 15 billion barrels of mobile oil remaining in U.S. fluvial-dominated deltaic reservoirs. Complex architecture and rapid lateral variability in such reservoirs complicate subsurface prediction, particularly in mature fields where well logs are the only available subsurface data. A genetic-stratigraphy-based methodology has been developed that improves between-well prediction of deltaic reservoir architecture and, thus, reduces risks associated with infill-drilling. In the area of Tijerina-Canales-Blucher (T-C-B) field, the productive 3rd-order Lower Frio unit was subdivided into eight 4th-order genetic units. Delta-front positions were identified on the basis of regional and subregional cross sections. The 4th-order units (30 to 80 ft thick) were subdivided into two five 5th-order units (10 to 30 ft thick). Log patterns and n sandstone maps were used to identify facies, which include (1) distributary channels (up to 25 ft thick, <1,000 to >8,000 ft wide, and commonly narrower than 40-acre well spacing), (2) mouth bars (up to 15 ft thick, ranging in size from 40 to 640 acres in area, commonly <320 acres), (3) bayfill splays (up to 10 ft thick, 20 to 700 acres in area, and commonly <160 acres), (4) wave-reworked delta fronts (up to 35 ft thick, and >5,000 ft wide), and (5) washover fans (up to 10 ft thick, and 7,000 ft wide). Many reservoir compartments, including the prolific 21-B interval, contain a significant degree of stratigraphic trapping caused by updip pinchout of delta front or washover sandstones or convex-updip segments of meandering distributary channel sandstones. The methodology and results of this study are directly applicable to other Gulf Coast fluvial-deltaic reservoirs in the Frio Formation and Wilcox Group, as well as to deltaic reservoirs throughout the U.S.

  8. Modelling of fractured reservoirs. Case of multi-scale media; Modelisation des reservoirs fractures. Cas des milieux multi-echelles

    Energy Technology Data Exchange (ETDEWEB)

    Henn, N.

    2000-12-13

    Some of the most productive oil and gas reservoirs are found in formations crossed by multi-scale fractures/faults. Among them, conductive faults may closely control reservoir performance. However, their modelling encounters numerical and physical difficulties linked with (a) the necessity to keep an explicit representation of faults through small-size grid blocks, (b) the modelling of multiphase flow exchanges between the fault and the neighbouring medium. In this thesis, we propose a physically-representative and numerically efficient modelling approach in order to incorporate sub-vertical conductive faults in single and dual-porosity simulators. To validate our approach and demonstrate its efficiency, simulation results of multiphase displacements in representative field sector models are presented. (author)

  9. Nonlinear Memory Capacity of Parallel Time-Delay Reservoir Computers in the Processing of Multidimensional Signals.

    Science.gov (United States)

    Grigoryeva, Lyudmila; Henriques, Julie; Larger, Laurent; Ortega, Juan-Pablo

    2016-07-01

    This letter addresses the reservoir design problem in the context of delay-based reservoir computers for multidimensional input signals, parallel architectures, and real-time multitasking. First, an approximating reservoir model is presented in those frameworks that provides an explicit functional link between the reservoir architecture and its performance in the execution of a specific task. Second, the inference properties of the ridge regression estimator in the multivariate context are used to assess the impact of finite sample training on the decrease of the reservoir capacity. Finally, an empirical study is conducted that shows the adequacy of the theoretical results with the empirical performances exhibited by various reservoir architectures in the execution of several nonlinear tasks with multidimensional inputs. Our results confirm the robustness properties of the parallel reservoir architecture with respect to task misspecification and parameter choice already documented in the literature.

  10. Architecture of the Product State Model Environment

    DEFF Research Database (Denmark)

    Holm Larsen, Michael; Lynggaard, Hans Jørgen B.

    2003-01-01

    technologies already haveproved their worth in the design and engineering phases of shipbuilding and in the operation phase.However, the handling of product information on the shop floor is not yet equally developed.The paper reports from the Brite-Euram project (No. BE97-4510) QualiGlobe focusing...... on thedevelopment activities of the PSM architecture. An example discusses how to handle product relatedinformation on the shop floor in a manufacturing company and focuses on how dynamically updatedproduct data can improve control of production activities. This prototype example of welding a jointbetween two steel...

  11. Demand Activated Manufacturing Architecture (DAMA) model for supply chain collaboration

    Energy Technology Data Exchange (ETDEWEB)

    CHAPMAN,LEON D.; PETERSEN,MARJORIE B.

    2000-03-13

    The Demand Activated Manufacturing Architecture (DAMA) project during the last five years of work with the U.S. Integrated Textile Complex (retail, apparel, textile, and fiber sectors) has developed an inter-enterprise architecture and collaborative model for supply chains. This model will enable improved collaborative business across any supply chain. The DAMA Model for Supply Chain Collaboration is a high-level model for collaboration to achieve Demand Activated Manufacturing. The five major elements of the architecture to support collaboration are (1) activity or process, (2) information, (3) application, (4) data, and (5) infrastructure. These five elements are tied to the application of the DAMA architecture to three phases of collaboration - prepare, pilot, and scale. There are six collaborative activities that may be employed in this model: (1) Develop Business Planning Agreements, (2) Define Products, (3) Forecast and Plan Capacity Commitments, (4) Schedule Product and Product Delivery, (5) Expedite Production and Delivery Exceptions, and (6) Populate Supply Chain Utility. The Supply Chain Utility is a set of applications implemented to support collaborative product definition, forecast visibility, planning, scheduling, and execution. The DAMA architecture and model will be presented along with the process for implementing this DAMA model.

  12. Nutrient Response Modeling in Falls of the Neuse Reservoir

    Science.gov (United States)

    Lin, Jing; Li, Jie

    2011-03-01

    In order to study system responses of Falls of the Neuse Reservoir (Falls Lake) to varied nutrient loadings, a coupled three-dimensional hydrodynamic and eutrophication model was applied. The model was calibrated using 2005 and 2006 intensive survey data, and validated using 2007 survey data. Compared with historical hydrological records, 2005 and 2007 were considered as dry years and 2006 was recognized as a normal year. Relatively higher nutrient fluxes from the sediment were specified for dry year model simulations. The differences were probably due to longer residence time and hence higher nutrient retention rate during dry years in Falls Lake. During the normal year of 2006, approximately 70% of total nitrogen (TN) and 80% of total phosphorus (TP) were delivered from the tributaries; about 20% (TN and TP) were from the sediment bottom. During the dry years of 2005 and 2007, the amount of TN released from sediment was equivalent to that introduced from the tributaries, indicating the critical role of nutrient recycling within the system in dry years. The model results also suggest that both nitrogen and phosphorus are limiting phytoplankton growth in Falls Lake. In the upper part of the lake where high turbidity was observed, nitrogen limitation appeared to dominate. Scenario model runs also suggest that great nutrient loading reductions are needed for Falls Lake to meet the water quality standard.

  13. Research on Architecture of Enterprise Modeling in Workflow System

    Institute of Scientific and Technical Information of China (English)

    李伟平; 齐慧彬; 薛劲松; 朱云龙

    2002-01-01

    The market that an enterprise is faced is changing and can 't be forecastedaccurately in this information time. In order to find the chances in the marketpractitioners have focused on business processes through their re-engineeringprogramme to improve enterprise efficiency. It is necessary to manage an enterpriseusing process-based method for the requirement of enhancing work efficiency and theability of competition in the market. And information system developers haveemphasized the use of standard models to accelerate the speed of configuration andimplementation of integrated systems for enterprises. So we have to model anenterprise with process-based modeling method. An architecture of enterprise modelingis presented in this paper. This architecture is composed of four views and supportingthe whole lifecycle of enterprise model. Because workflow management system is basedon process definition, this architecture can be directly used in the workflowmanagement system. The implement method of this model was thoroughly describedmeanwhile the workflow management software supporting the building and running themodel was also given.

  14. A Hierarchical Model Architecture for Enterprise Integration in Chemical Industries

    Institute of Scientific and Technical Information of China (English)

    华贲; 周章玉; 成思危

    2001-01-01

    Towards integration of supply chain, manufacturing/production and investment decision making, this paper presents a hierarchical model architecture which contains six sub-models covering the areas of manufacturing control, production operation, design and revamp, production management, supply chain and investment decision making. Six types of flow, material, energy, information, humanware, partsware and capital are ciasified. These flows connect enterprise components/subsystems to formulate system topology and logical structure. Enterprise components/subsystems are abstracted to generic elementary and composite classes. Finally, the model architecture is applied to a management system of an integrated suply chain, and suggestion are made on the usage of the model architecture and further development of the model as well as imvlementation issues.

  15. Modeling Tools for Drilling, Reservoir Navigation, and Formation Evaluation

    Directory of Open Access Journals (Sweden)

    Sushant Dutta

    2012-06-01

    successfully explains the unusual curve separations of an array laterolog tool in a shale-gas formation. The third example uses two-dimensional (2-D and 3-D modeling to prove the efficacy of a new borehole technology for reservoir monitoring.

  16. Modeling Tools for Drilling, Reservoir Navigation, and Formation Evaluation

    Directory of Open Access Journals (Sweden)

    Sushant Dutta

    2012-06-01

    successfully explains the unusual curve separations of an array laterolog tool in a shale-gas formation. The third example uses two-dimensional (2-D and 3-D modeling to prove the efficacy of a new borehole technology for reservoir monitoring.

  17. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2004-02-25

    The University of Alabama, in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company, has undertaken an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary goal of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. Geoscientific reservoir property, geophysical seismic attribute, petrophysical property, and engineering property characterization has shown that reef (thrombolite) and shoal reservoir lithofacies developed on the flanks of high-relief crystalline basement paleohighs (Vocation Field example) and on the crest and flanks of low-relief crystalline basement paleohighs (Appleton Field example). The reef thrombolite lithofacies have higher reservoir quality than the shoal lithofacies due to overall higher permeabilities and greater interconnectivity. Thrombolite dolostone flow units, which are dominated by dolomite intercrystalline and vuggy pores, are characterized by a pore system comprised of a higher percentage of large-sized pores and larger pore throats. Rock-fluid interactions (diagenesis) studies have shown that although the primary control on

  18. Improved reservoir modelling with time-lapse seismic data in a Gulf of Mexico gas condensate reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Waggoner, J.R.; Seymour, R.H.; Cominelli, A. [ENI/Agip Div., Milan (Italy); Stradiotti, A. [Agip Petroleum, Houston, TX (United States)

    2003-07-01

    Time-lapse 3D- or 4D-seismic data have been tried in several fields to date, with some good case studies published to demonstrate the utility of the 4D seismic information. While another 4D case study would be useful, this paper describes two novel aspects of a recent application in the Gulf of Mexico. First, the target reservoir contains a gas condensate fluid under primary depletion, so pressure, rather than saturation, changes create the observed 4D acoustic response. Further, the primary impact of the pressure change is to the fluid composition as the initially dense gas phase lightens as condensate drops out below the dew point. The result was a 2.8% change in acoustic impedance predicted in the feasibility study. Second, the 4D seismic result was used to constrain an optimized history-matching procedure, along with the production data. After describing the method used, the paper will discuss the changes to the reservoir model that resulted. While the results should not be considered unique, they do give some insight into the structure of the reservoir that should be considered for optimal reservoir management. (Author)

  19. Variogram Identification Aided by a Structural Framework for Improved Geometric Modeling of Faulted Reservoirs: Jeffara Basin, Southeastern Tunisia

    Energy Technology Data Exchange (ETDEWEB)

    Chihi, Hayet, E-mail: hayet_chihi@yahoo.fr; Bedir, Mourad [University of Cartage, Georesources Laboratory, Centre for Water Researches and Technologies (Tunisia); Belayouni, Habib [University of Tunis El Manar, Department of Geology, Faculty of Sciences of Tunis (Tunisia)

    2013-06-15

    This article describes a proposed work-sequence to generate accurate reservoir-architecture models, describing the geometry of bounding surfaces (i.e., fault locations and extents), of a structurally complex geologic setting in the Jeffara Basin (South East Tunisia) by means of geostatistical modeling. This uses the variogram as the main tool to measure the spatial variability of the studied geologic medium before making any estimation or simulation. However, it is not always easy to fit complex experimental variograms to theoretical models. Thus, our primary purpose was to establish a relationship between the geology and the components of the variograms to fit a mathematically consistent and geologically interpretable variogram model for improved predictions of surface geometries. We used a three-step approach based on available well data and seismic information. First, we determined the structural framework: a seismo-tectonic data analysis was carried out, and we showed that the study area is cut mainly by NW-SE-trending normal faults, which were classified according to geometric criteria (strike, throw magnitude, dip, and dip direction). We showed that these normal faults are at the origin of a large-scale trend structure (surfaces tilted toward the north-east). At a smaller scale, the normal faults create a distinct compartmentalization of the reservoirs. Then, a model of the reservoir system architecture was built by geostatistical methods. An efficient methodology was developed, to estimate the bounding faulted surfaces of the reservoir units. Emphasis was placed on (i) elaborating a methodology for variogram interpretation and modeling, whereby the importance of each variogram component is assessed in terms of probably geologic factor controlling the behavior of each structure; (ii) integrating the relevant fault characteristics, which were deduced from the previous fault classification analysis, as constraints in the kriging estimation of bounding surfaces

  20. Complex Modelling of Open System Design for Sustainable Architecture

    Science.gov (United States)

    Gu, Yan; Frazer, John

    This paper argues a model of complex system design for sustainable architecture within a framework of entropy evolution. The spectrum of sustainable architecture consists of the efficient use of energy and material resource in life-cycle of buildings, the active involvement of the occupants in micro-climate control within buildings, and the natural environmental context. The interactions of the parameters compose a complex system of sustainable architectural design, of which the conventional linear and fragmented design technologies are insufficient to indicate holistic and ongoing environmental performance. The complexity theory of dissipative structure states a microscopic formulation of open system evolution, which provides a system design framework for the evolution of building environmental performance towards an optimization of sustainability in architecture.

  1. Modelling of sedimentation processes inside Roseires Reservoir (Sudan)

    NARCIS (Netherlands)

    Omer, A.Y.A.; Ali, Y.S.A.; Roelvink, J.A.; Dastgheib, A.; Paron, P.; Crosato, A.

    2015-01-01

    Roseires Reservoir, located on the Blue Nile River in Sudan, is the first trap to the sediments coming from the vast upper river catchment in Ethiopia, which suffers from high erosion and desertification problems. The reservoir has already lost more than one-third of its storage capacity due to sedi

  2. Modelling of sedimentation processes inside Roseires Reservoir (Sudan) (discussion)

    NARCIS (Netherlands)

    Omer, A.Y.A.; Ali, Y.S.A.; Roelvink, J.A.; Dastgheib, A.; Paron, P.; Crosato, A.

    2014-01-01

    Discussion paper. Roseires Reservoir, located on the Blue Nile River, in Sudan, is the first trap to the sediments coming from the upper catchment in Ethiopia, which suffers from high erosion and desertification problems. The reservoir lost already more than one third of its 5 storage capacity due t

  3. Modelling of sedimentation processes inside Roseires Reservoir (Sudan) (abstract)

    NARCIS (Netherlands)

    Ali, Y.S.A.; Omer, A.Y.A.; Crosato, A.

    2013-01-01

    Roseires Reservoir is located on the Blue Nile River, in Sudan (figure 1). It is the first trap to the sediments coming from the upper catchment in Ethiopia, which suffers from high erosion and desertification problems. The reservoir lost already more than one third of its storage capacity due to se

  4. Modeling Study of High Pressure and High Temperature Reservoir Fluids

    DEFF Research Database (Denmark)

    Varzandeh, Farhad

    to 250 °C and 2400 bar, in the deep petroleum reservoirs. Furthermore, many of these deep reservoirs are found offshore, including the North Sea and the Gulf of Mexico, making the development even more risky. On the other hand, development of these high pressure high temperature (HPHT) fields can...

  5. A 3D forward stratigraphic model of fluvial meander-bend evolution for prediction of point-bar lithofacies architecture

    Science.gov (United States)

    Yan, Na; Mountney, Nigel P.; Colombera, Luca; Dorrell, Robert M.

    2017-08-01

    Although fundamental types of fluvial meander-bend transformations - expansion, translation, rotation, and combinations thereof - are widely recognised, the relationship between the migratory behaviour of a meander bend, and its resultant accumulated sedimentary architecture and lithofacies distribution remains relatively poorly understood. Three-dimensional data from both currently active fluvial systems and from ancient preserved successions known from outcrop and subsurface settings are limited. To tackle this problem, a 3D numerical forward stratigraphic model - the Point-Bar Sedimentary Architecture Numerical Deduction (PB-SAND) - has been devised as a tool for the reconstruction and prediction of the complex spatio-temporal migratory evolution of fluvial meanders, their generated bar forms and the associated lithofacies distributions that accumulate as heterogeneous fluvial successions. PB-SAND uses a dominantly geometric modelling approach supplemented by process-based and stochastic model components, and is constrained by quantified sedimentological data derived from modern point bars or ancient successions that represent suitable analogues. The model predicts the internal architecture and geometry of fluvial point-bar elements in three dimensions. The model is applied to predict the sedimentary lithofacies architecture of ancient preserved point-bar and counter-point-bar deposits of the middle Jurassic Scalby Formation (North Yorkshire, UK) to demonstrate the predictive capabilities of PB-SAND in modelling 3D architectures of different types of meander-bend transformations. PB-SAND serves as a practical tool with which to predict heterogeneity in subsurface hydrocarbon reservoirs and water aquifers.

  6. Advanced Techniques for Reservoir Simulation and Modeling of Non-Conventional Wells

    Energy Technology Data Exchange (ETDEWEB)

    Durlofsky, Louis J.

    2000-08-28

    This project targets the development of (1) advanced reservoir simulation techniques for modeling non-conventional wells; (2) improved techniques for computing well productivity (for use in reservoir engineering calculations) and well index (for use in simulation models), including the effects of wellbore flow; and (3) accurate approaches to account for heterogeneity in the near-well region.

  7. Fast Multiscale Reservoir Simulations using POD-DEIM Model Reduction

    KAUST Repository

    Ghasemi, Mohammadreza

    2015-02-23

    In this paper, we present a global-local model reduction for fast multiscale reservoir simulations in highly heterogeneous porous media with applications to optimization and history matching. Our proposed approach identifies a low dimensional structure of the solution space. We introduce an auxiliary variable (the velocity field) in our model reduction that allows achieving a high degree of model reduction. The latter is due to the fact that the velocity field is conservative for any low-order reduced model in our framework. Because a typical global model reduction based on POD is a Galerkin finite element method, and thus it can not guarantee local mass conservation. This can be observed in numerical simulations that use finite volume based approaches. Discrete Empirical Interpolation Method (DEIM) is used to approximate the nonlinear functions of fine-grid functions in Newton iterations. This approach allows achieving the computational cost that is independent of the fine grid dimension. POD snapshots are inexpensively computed using local model reduction techniques based on Generalized Multiscale Finite Element Method (GMsFEM) which provides (1) a hierarchical approximation of snapshot vectors (2) adaptive computations by using coarse grids (3) inexpensive global POD operations in a small dimensional spaces on a coarse grid. By balancing the errors of the global and local reduced-order models, our new methodology can provide an error bound in simulations. Our numerical results, utilizing a two-phase immiscible flow, show a substantial speed-up and we compare our results to the standard POD-DEIM in finite volume setup.

  8. Modeling the vertical motion of drops bouncing on a bounded fluid reservoir

    Science.gov (United States)

    Blanchette, François

    2016-03-01

    We present a first-principles model of drops bouncing on a liquid reservoir. We consider a nearly inviscid liquid reservoir and track the waves that develop in a bounded domain. Bouncing drops are modeled as vertical linear springs. We obtain an expression for the contact force between drop and liquid surface and a model where the only adjustable parameter is an effective viscosity used to describe the waves on the reservoir's surface. With no adjustable parameters associated to the drop, we recover experimental bouncing times and restitution coefficients. We use our model to describe the effect of the Bond, Ohnesorge, and Weber numbers on drops bouncing on a stationary reservoir. We also use our model to describe drops bouncing on an oscillated reservoir, describing various bouncing modes and a walking threshold.

  9. More Novel Hantaviruses and Diversifying Reservoir Hosts — Time for Development of Reservoir-Derived Cell Culture Models?

    Directory of Open Access Journals (Sweden)

    Isabella Eckerle

    2014-02-01

    Full Text Available Due to novel, improved and high-throughput detection methods, there is a plethora of newly identified viruses within the genus Hantavirus. Furthermore, reservoir host species are increasingly recognized besides representatives of the order Rodentia, now including members of the mammalian orders Soricomorpha/Eulipotyphla and Chiroptera. Despite the great interest created by emerging zoonotic viruses, there is still a gross lack of in vitro models, which reflect the exclusive host adaptation of most zoonotic viruses. The usually narrow host range and genetic diversity of hantaviruses make them an exciting candidate for studying virus-host interactions on a cellular level. To do so, well-characterized reservoir cell lines covering a wide range of bat, insectivore and rodent species are essential. Most currently available cell culture models display a heterologous virus-host relationship and are therefore only of limited value. Here, we review the recently established approaches to generate reservoir-derived cell culture models for the in vitro study of virus-host interactions. These successfully used model systems almost exclusively originate from bats and bat-borne viruses other than hantaviruses. Therefore we propose a parallel approach for research on rodent- and insectivore-borne hantaviruses, taking the generation of novel rodent and insectivore cell lines from wildlife species into account. These cell lines would be also valuable for studies on further rodent-borne viruses, such as orthopox- and arenaviruses.

  10. Sub-grid parameterisation of fluvio-deltaic processes and architecture in a basin-scale stratigraphic model

    Science.gov (United States)

    Dalman, Rory A. F.; Weltje, Gert Jan

    2008-10-01

    We present a parameterisation of fluvio-deltaic drainage network evolution and alluvial architecture in a basin-scale 2-DH model. The model setup is capable of producing convergent and divergent channel networks. Major elements are the alluvial-ridge aggradation and the coupled overbank deposition, the dimension and style of the channel belt and the sub-grid stratigraphic expression. Avulsions are allowed to develop out of randomly instigated crevasses. Channel stability is modelled one dimensionally by calculating the flow and sediment transport at prospective avulsion nodes. The ultimate fate of crevasses (failed avulsion, successful avulsion, stable bifurcation) depends on the ratio of cross-valley and in-channel gradients in the local neighbourhood of the grid cell under consideration and on the amount and distribution of the suspended sediment load in the water column. The sub-grid parameterisation yields implicit knowledge of the alluvial architecture, which may be analysed stochastically. Stochastic realisations of the alluvial architecture allow us to investigate the relationship between basin-fill architecture and small-scale alluvial architecture, which is likely to improve geological reservoir modelling of these notoriously complex deposits. Modelling results under conditions of time-invariant forcing indicate significant quasi-cyclic autogenic behaviour of the fluvio-deltaic system. Changes in the avulsion frequency are correlated with the number and length of distributary channels, which are in turn related to alternating phases of progradational and aggradational delta development. The resulting parasequences may be difficult to distinguish from their allogenically induced counterparts.

  11. Evolution of Modelling Techniques for Service Oriented Architecture

    Directory of Open Access Journals (Sweden)

    Mikit Kanakia

    2014-07-01

    Full Text Available Service-oriented architecture (SOA is a software design and architecture design pattern based on independent pieces of software providing functionality as services to other applications. The benefit of SOA in the IT infrastructure is to allow parallel use and data exchange between programs which are services to the enterprise. Unified Modelling Language (UML is a standardized general-purpose modelling language in the field of software engineering. The UML includes a set of graphic notation techniques to create visual models of object-oriented software systems. We want to make UML available for SOA as well. SoaML (Service oriented architecture Modelling Language is an open source specification project from the Object Management Group (OMG, describing a UML profile and meta-model for the modelling and design of services within a service-oriented architecture. BPMN was also extended for SOA but there were few pitfalls. There is a need of a modelling framework which dedicated to SOA. Michael Bell authored a framework called Service Oriented Modelling Framework (SOMF which is dedicated for SOA.

  12. Modeling of Turbidity Variation in Two Reservoirs Connected by a Water Transfer Tunnel in South Korea

    Directory of Open Access Journals (Sweden)

    Jae Chung Park

    2017-06-01

    Full Text Available The Andong and Imha reservoirs in South Korea are connected by a water transfer tunnel. The turbidity of the Imha reservoir is much higher than that of the Andong reservoir. Thus, it is necessary to examine the movement of turbidity between the two reservoirs via the water transfer tunnel. The aim of this study was to investigate the effect of the water transfer tunnel on the turbidity behavior of the two connecting reservoirs and to further understand the effect of reservoir turbidity distribution as a function of the selective withdrawal depth. This study applied the CE-QUAL-W2, a water quality and 2-dimensional hydrodynamic model, for simulating the hydrodynamic processes of the two reservoirs. Results indicate that, in the Andong reservoir, the turbidity of the released water with the water transfer tunnel was similar to that without the tunnel. However, in the Imha reservoir, the turbidity of the released water with the water transfer tunnel was lower than that without the tunnel. This can be attributed to the higher capacity of the Andong reservoir, which has double the storage of the Imha reservoir. Withdrawal turbidity in the Imha reservoir was investigated using the water transfer tunnel. This study applied three withdrawal selections as elevation (EL. 141.0 m, 146.5 m, and 152.0 m. The highest withdrawal turbidity resulted in EL. 141.0 m, which indicates that the high turbidity current is located at a vertical depth of about 20–30 m because of the density difference. These results will be helpful for understanding the release and selective withdrawal turbidity behaviors for a water transfer tunnel between two reservoirs.

  13. Application of Stochastic Partial Differential Equations to Reservoir Property Modelling

    KAUST Repository

    Potsepaev, R.

    2010-09-06

    Existing algorithms of geostatistics for stochastic modelling of reservoir parameters require a mapping (the \\'uvt-transform\\') into the parametric space and reconstruction of a stratigraphic co-ordinate system. The parametric space can be considered to represent a pre-deformed and pre-faulted depositional environment. Existing approximations of this mapping in many cases cause significant distortions to the correlation distances. In this work we propose a coordinate free approach for modelling stochastic textures through the application of stochastic partial differential equations. By avoiding the construction of a uvt-transform and stratigraphic coordinates, one can generate realizations directly in the physical space in the presence of deformations and faults. In particular the solution of the modified Helmholtz equation driven by Gaussian white noise is a zero mean Gaussian stationary random field with exponential correlation function (in 3-D). This equation can be used to generate realizations in parametric space. In order to sample in physical space we introduce a stochastic elliptic PDE with tensor coefficients, where the tensor is related to correlation anisotropy and its variation is physical space.

  14. An updated conceptual model of the Los Humeros geothermal reservoir (Mexico)

    Science.gov (United States)

    Arellano, V. M.; García, A.; Barragán, R. M.; Izquierdo, G.; Aragón, A.; Nieva, D.

    2003-05-01

    An analysis of production and reservoir engineering data of 42 wells from the Los Humeros geothermal field (Mexico) allowed obtaining the pressure and temperature profiles for the unperturbed reservoir fluids and developing 1-D and 2-D models for the reservoir. Results showed the existence of at least two reservoirs in the system: a relatively shallow liquid-dominant reservoir located between 1025 and 1600 m above sea level (a.s.l.) the pressure profile of which corresponds to a 300-330°C boiling water column and a deeper low-liquid-saturation reservoir located between 850 and 100 m a.s.l. with temperatures between 300 and 400°C. Both reservoirs seem to be separated by a vitreous tuff lithological unit, but hydraulic connectivity occurs through faults and fractures of the system, allowing deep steam to ascend while condensate flows down (porous heat pipe). The geochemical and isotopic (δ 18O, δD) composition of the produced fluids can be explained as the result of a boiling process with reservoir steam separation and partial condensation, a fact that agrees with the proposed reservoir engineering model.

  15. Seismic Sedimentology Interpretation Method of Meandering Fluvial Reservoir:From Model to Real Data

    Institute of Scientific and Technical Information of China (English)

    Tao Zhang; Xianguo Zhang; Chengyan Lin; Jingfeng Yu; Shouxiu Zhang

    2015-01-01

    Reservoir architecture of meandering river deposition is complex and traditional seismic facies interpretation method cannot characterize it when layer thickness is under seismic vertical reso-lution. In this study, a seismic sedimentology interpretation method and workflow for point bar char-acterization is built. Firstly, the influences of seismic frequency and sandstone thickness on seismic re-flection are analyzed by outcrop detection with ground penetrating radar (GPR) and seismic forward modeling. It is found that (1) sandstone thickness can influence seismic reflection of point bar architec-ture. With the increasing of sandstone thickness from 1/4 wavelength (λ) to λ/2, seismic reflection ge-ometries various from ambiguous reflection,“V”type reflection to“X”type reflection;(2) seismic fre-quency can influence reservoirs’ seismic reflection geometry. Seismic events follow inclined lateral ag-gradation surfaces, which is isochronic depositional boundaries, in high frequency seismic data while the events extend along lithologic surfaces, which are level, in low frequency data. Secondly, strata slice interpretation method for thin layer depositional characterization is discussed with seismic forward modeling. Lastly, a method and workflow based on the above study is built which includes seismic fre-quency analysis, 90º phasing, stratal slicing and integrated interpretation of slice and seismic profile. This method is used in real data study in Tiger shoal, the Gulf of Mexico. Two episodes of meandering fluvial deposition is recognized in the study layer. Sandstone of the lower unit, which is formed in low base level stage, distributes limited. Sandstone distribution dimension and channel sinuosity become larger in the upper layer, which is high base level deposition.

  16. MISTRAL: A language for model transformations in the MOF meta-modeling architecture

    NARCIS (Netherlands)

    Kurtev, I.; Berg, van den K.G.

    2005-01-01

    In the Meta Object Facility (MOF) meta-modeling architecture a number of model transformation scenarios can be identified. It could be expected that a meta-modeling architecture will be accompanied by a transformation technology supporting the model transformation scenarios in a uniform way. Despite

  17. Extending enterprise architecture modelling with business goals and requirements

    Science.gov (United States)

    Engelsman, Wilco; Quartel, Dick; Jonkers, Henk; van Sinderen, Marten

    2011-02-01

    The methods for enterprise architecture (EA), such as The Open Group Architecture Framework, acknowledge the importance of requirements modelling in the development of EAs. Modelling support is needed to specify, document, communicate and reason about goals and requirements. The current modelling techniques for EA focus on the products, services, processes and applications of an enterprise. In addition, techniques may be provided to describe structured requirements lists and use cases. Little support is available however for modelling the underlying motivation of EAs in terms of stakeholder concerns and the high-level goals that address these concerns. This article describes a language that supports the modelling of this motivation. The definition of the language is based on existing work on high-level goal and requirements modelling and is aligned with an existing standard for enterprise modelling: the ArchiMate language. Furthermore, the article illustrates how EA can benefit from analysis techniques from the requirements engineering domain.

  18. An architecture for integration of multidisciplinary models

    DEFF Research Database (Denmark)

    Belete, Getachew F.; Voinov, Alexey; Holst, Niels

    2014-01-01

    , integration of models requires us to address technical, semantic, and dataset aspects of interoperability. So we need a genuine techniques that enable us to integrate various domain specific models for interdisciplinary study. In this research work, we investigated best practices of System Integration......Integrating multidisciplinary models requires linking models: that may operate at different temporal and spatial scales; developed using different methodologies, tools and techniques; different levels of complexity; calibrated for different ranges of inputs and outputs, etc. On the other hand...

  19. Modelling Orthorhombic Anisotropic Effects for Reservoir Fracture Characterization of a Naturally Fractured Tight Carbonate Reservoir, Onshore Texas, USA

    Science.gov (United States)

    Osinowo, Olawale Olakunle; Chapman, Mark; Bell, Rebecca; Lynn, Heloise B.

    2017-09-01

    In this study we present a step-by-step theoretical modelling approach, using established seismic wave propagation theories in anisotropic media, to generate unique anisotropic reflection patterns observed from three-dimensional pure-mode pressure (3D-PP), full-azimuth and full-offset seismic reflection data acquired over a naturally fractured tight carbonate field, onshore Texas, USA. Our aim is to gain an insight into the internal structures of the carbonate reservoir responsible for the observed anisotropic reflection patterns. From the generated model we were able to establish that the observed field seismic reflection patterns indicate azimuthal anisotropy in the form of crack induced shear-wave splitting and variation in P-wave velocity with offset and azimuth. Amplitude variation with azimuth (AVAZ) analysis also confirmed multi-crack sets induced anisotropy which is characteristic of orthorhombic symmetry, evident as multiple bright and dim-amplitude azimuth directions as well as complete reversal of bright-amplitude to dim-amplitude azimuth direction as the angle of incidence increases from near (≤15°) to mid (≥30°) offsets. Finally, we fitted the generated P-wave velocity into an ellipse to determine the intensity and orientation (N26E) of the open crack set as well as the direction of the minimum in situ stress axis (N116E) within the reservoir. The derived information served as an aid for the design of horizontal well paths that would intercept open fractures and ensure production optimization of the carbonate reservoir, which was on production decline despite reservoir studies that indicate un-depleted reserves.

  20. 3D Geostatistical Modeling and Uncertainty Analysis in a Carbonate Reservoir, SW Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Kamali

    2013-01-01

    Full Text Available The aim of geostatistical reservoir characterization is to utilize wide variety of data, in different scales and accuracies, to construct reservoir models which are able to represent geological heterogeneities and also quantifying uncertainties by producing numbers of equiprobable models. Since all geostatistical methods used in estimation of reservoir parameters are inaccurate, modeling of “estimation error” in form of uncertainty analysis is very important. In this paper, the definition of Sequential Gaussian Simulation has been reviewed and construction of stochastic models based on it has been discussed. Subsequently ranking and uncertainty quantification of those stochastically populated equiprobable models and sensitivity study of modeled properties have been presented. Consequently, the application of sensitivity analysis on stochastic models of reservoir horizons, petrophysical properties, and stochastic oil-water contacts, also their effect on reserve, clearly shows any alteration in the reservoir geometry has significant effect on the oil in place. The studied reservoir is located at carbonate sequences of Sarvak Formation, Zagros, Iran; it comprises three layers. The first one which is located beneath the cap rock contains the largest portion of the reserve and other layers just hold little oil. Simulations show that average porosity and water saturation of the reservoir is about 20% and 52%, respectively.

  1. A preliminary evaluation model for reservoir hydrocarbon-generating potential established based on dissolved hydrocarbons in oilfield water

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A large number of oilfield water samples were analyzed in this work. Research on the relationship between the concentrations and distribution of dissolved hydrocarbons sug gested that the contents and composition of dissolved hydrocarbons varied with the hydrocar bon-generating potential of reservoirs. The concentrations of dissolved hydrocarbons were low in dry layers, water layers and gas-water layers, but high in gas reservoirs and oil reservoirs, especially in gas reservoirs with condensed oil. Series of carbon-number alkanes were usually absent in oilfield water from dry layers, water layers and gas-water layers but abundant in oil field water from oil-water reservoirs, gas reservoirs and oil reservoirs, whose carbon numbers varied most widely in oil reservoirs and least in gas reservoirs. A preliminary evaluation model for reservoir hydrocarbon-generating potential was established based on the characteristics of dissolved hydrocarbons in oilfield water to assist hydrocarbon exploration.

  2. Human Spaceflight Architecture Model (HSFAM) Data Dictionary

    Science.gov (United States)

    Shishko, Robert

    2016-01-01

    HSFAM is a data model based on the DoDAF 2.02 data model with some for purpose extensions. These extensions are designed to permit quantitative analyses regarding stakeholder concerns about technical feasibility, configuration and interface issues, and budgetary and/or economic viability.

  3. Integrating a reservoir regulation scheme into a spatially distributed hydrological model

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Gang; Gao, Huilin; Naz, Bibi S.; Kao, Shih-Chieh; Voisin, Nathalie

    2016-12-01

    During the past several decades, numerous reservoirs have been built across the world for a variety of purposes such as flood control, irrigation, municipal/industrial water supplies, and hydropower generation. Consequently, natural streamflow timing and magnitude have been altered significantly by reservoir operations. In addition, the hydrological cycle can be modified by land use/land cover and climate changes. To understand the fine scale feedback between hydrological processes and water management decisions, a distributed hydrological model embedded with a reservoir component is of desire. In this study, a multi-purpose reservoir module with predefined complex operational rules was integrated into the Distributed Hydrology Soil Vegetation Model (DHSVM). Conditional operating rules, which are designed to reduce flood risk and enhance water supply reliability, were adopted in this module. The performance of the integrated model was tested over the upper Brazos River Basin in Texas, where two U.S. Army Corps of Engineers reservoirs, Lake Whitney and Aquilla Lake, are located. The integrated DHSVM model was calibrated and validated using observed reservoir inflow, outflow, and storage data. The error statistics were summarized for both reservoirs on a daily, weekly, and monthly basis. Using the weekly reservoir storage for Lake Whitney as an example, the coefficients of determination (R2) and the Nash-Sutcliff Efficiency (NSE) are 0.85 and 0.75, respectively. These results suggest that this reservoir module has promise for use in sub-monthly hydrological simulations. Enabled with the new reservoir component, the DHSVM model provides a platform to support adaptive water resources management under the impacts of evolving anthropogenic activities and substantial environmental changes.

  4. RT 24 - Architecture, Modeling & Simulation, and Software Design

    Science.gov (United States)

    2010-11-01

    focus on tool extensions (UPDM, SysML, SoaML, BPMN ) Leverage “best of breed” architecture methodologies Provide tooling to support the methodology DoDAF...Capability 10 Example: BPMN 11 DoDAF 2.0 MetaModel BPMN MetaModel Mapping SysML to DoDAF 2.0 12 DoDAF V2.0 Models OV-2 SysML Diagrams Requirement

  5. EVA/ORU model architecture using RAMCOST

    Science.gov (United States)

    Ntuen, Celestine A.; Park, Eui H.; Wang, Y. M.; Bretoi, R.

    1990-01-01

    A parametrically driven simulation model is presented in order to provide a detailed insight into the effects of various input parameters in the life testing of a modular space suit. The RAMCOST model employed is a user-oriented simulation model for studying the life-cycle costs of designs under conditions of uncertainty. The results obtained from the EVA simulated model are used to assess various mission life testing parameters such as the number of joint motions per EVA cycle time, part availability, and number of inspection requirements. RAMCOST first simulates EVA completion for NASA application using a probabilistic like PERT network. With the mission time heuristically determined, RAMCOST then models different orbital replacement unit policies with special application to the astronaut's space suit functional designs.

  6. Improving Project Management Using Formal Models and Architectures

    Science.gov (United States)

    Kahn, Theodore; Sturken, Ian

    2011-01-01

    This talk discusses the advantages formal modeling and architecture brings to project management. These emerging technologies have both great potential and challenges for improving information available for decision-making. The presentation covers standards, tools and cultural issues needing consideration, and includes lessons learned from projects the presenters have worked on.

  7. Building information modeling in the architectural design phases

    DEFF Research Database (Denmark)

    Hermund, Anders

    2009-01-01

    with an architectural quality? In Denmark the implementation of the digital working methods related to BIM has been introduced by government law in 2007. Will the important role of the architect as designer change in accordance with these new methods, and does the idea of one big integrated model represent a paradox...... in relation to designing? The BIM mindset requires changes on many levels....

  8. Simulation and optimisation modelling approach for operation of the Hoa Binh Reservoir, Vietnam

    DEFF Research Database (Denmark)

    Ngo, Long le; Madsen, Henrik; Rosbjerg, Dan

    2007-01-01

    Hoa Binh, the largest reservoir in Vietnam, plays an important role in flood control for the Red River delta and hydropower generation. Due to its multi-purpose character, conflicts and disputes in operating the reservoir have been ongoing since its construction, particularly in the flood season......, the hydro-meteorological conditions, and the time of the year. A heuristic global optimisation tool, the shuffled complex evolution (SCE) algorithm, is adopted for optimising the reservoir operation. The optimisation puts focus on the trade-off between flood control and hydropower generation for the Hoa....... This paper proposes to optimise the control strategies for the Hoa Binh reservoir operation by applying a combination of simulation and optimisation models. The control strategies are set up in the MIKE 11 simulation model to guide the releases of the reservoir system according to the current storage level...

  9. Architecture on Architecture

    DEFF Research Database (Denmark)

    Olesen, Karen

    2016-01-01

    This paper will discuss the challenges faced by architectural education today. It takes as its starting point the double commitment of any school of architecture: on the one hand the task of preserving the particular knowledge that belongs to the discipline of architecture, and on the other hand...... the obligation to prepare students to perform in a profession that is largely defined by forces outside that discipline. It will be proposed that the autonomy of architecture can be understood as a unique kind of information: as architecture’s self-reliance or knowledge-about itself. A knowledge...... that is not scientific or academic but is more like a latent body of data that we find embedded in existing works of architecture. This information, it is argued, is not limited by the historical context of the work. It can be thought of as a virtual capacity – a reservoir of spatial configurations that can...

  10. A Global Hydrological Model with Reservoir Operation Scheme: Global and Regional Applications (Invited)

    Science.gov (United States)

    Hanasaki, N.; Masaki, Y.; Mateo, C.; Kanae, S.; Oki, T.

    2013-12-01

    More than 45000 large dams have been constructed all over the world, and their total storage capacity exceeds 7000 km3 which corresponds to approximately 20% of the total annual global river discharge. Explicit incorporation of reservoir operation is indispensable for global-/macro-scale hydrological models, since their storage capacity and potential of altering flow regime are too large to neglect. Our presentation consists of three parts. In the first part, the H08 model, a global hydrological model with reservoir operation scheme is introduced. The H08 model includes an algorithm to estimate reservoir operating rules of individual reservoirs. This enables us to apply the model to the regions and periods with no recorded reservoir operation. The key concepts and challenges of the model are discussed. In the second part, the role of reservoirs in water scarcity is globally assessed. In many parts of the world, local people are suffered from temporal variability in precipitation and river flow. The contribution of reservoirs to water scarcity alleviation is quantitatively and globally assessed. The assessment is extended to the future periods utilizing the latest climate and socio-economic scenarios. In the last part, a regional model application is introduced. The Chao Phraya River in Thailand was suffered from a severe flood in 2011. Vast area was inundated for months and the economic damages reached 40 billion USD. The Chao Phraya River has two major reservoirs and their role is crucial for both water use and flood control. The H08 model is substantially enhanced and applied to the basin to reproduce the 2011 floods. The tradeoff between water use and flood control was investigated by changing reservoir operation options.

  11. Modeling Virtual Organization Architecture with the Virtual Organization Breeding Methodology

    Science.gov (United States)

    Paszkiewicz, Zbigniew; Picard, Willy

    While Enterprise Architecture Modeling (EAM) methodologies become more and more popular, an EAM methodology tailored to the needs of virtual organizations (VO) is still to be developed. Among the most popular EAM methodologies, TOGAF has been chosen as the basis for a new EAM methodology taking into account characteristics of VOs presented in this paper. In this new methodology, referred as Virtual Organization Breeding Methodology (VOBM), concepts developed within the ECOLEAD project, e.g. the concept of Virtual Breeding Environment (VBE) or the VO creation schema, serve as fundamental elements for development of VOBM. VOBM is a generic methodology that should be adapted to a given VBE. VOBM defines the structure of VBE and VO architectures in a service-oriented environment, as well as an architecture development method for virtual organizations (ADM4VO). Finally, a preliminary set of tools and methods for VOBM is given in this paper.

  12. Modeling Virtual Organization Architecture with the Virtual Organization Breeding Methodology

    CERN Document Server

    Paszkiewicz, Zbigniew

    2011-01-01

    While Enterprise Architecture Modeling (EAM) methodologies become more and more popular, an EAM methodology tailored to the needs of virtual organizations (VO) is still to be developed. Among the most popular EAM methodologies, TOGAF has been chosen as the basis for a new EAM methodology taking into account characteristics of VOs presented in this paper. In this new methodology, referred as Virtual Organization Breeding Methodology (VOBM), concepts developed within the ECOLEAD project, e.g. the concept of Virtual Breeding Environment (VBE) or the VO creation schema, serve as fundamental elements for development of VOBM. VOBM is a generic methodology that should be adapted to a given VBE. VOBM defines the structure of VBE and VO architectures in a service-oriented environment, as well as an architecture development method for virtual organizations (ADM4VO). Finally, a preliminary set of tools and methods for VOBM is given in this paper.

  13. Architecture of the Product State Model Environment

    DEFF Research Database (Denmark)

    Holm Larsen, Michael; Lynggaard, Hans Jørgen B.

    2003-01-01

    This paper addresses the issue of using product models to support product lifecycle activities withparticular focus on the production phase. The motivation of the research is that products are producedmore costly and with longer lead-time than necessary.The paper provides a review of product...... modelling technologies and approaches, and the overallarchitecture for the Product State Model (PSM) Environment as a basis for quality monitoring.Especially, the paper focuses on the circumstances prevailing in a one-of-a-kind manufacturingenvironment like the shipbuilding industry, where product modelling...... technologies already haveproved their worth in the design and engineering phases of shipbuilding and in the operation phase.However, the handling of product information on the shop floor is not yet equally developed.The paper reports from the Brite-Euram project (No. BE97-4510) QualiGlobe focusing...

  14. Integrating a reservoir regulation scheme into a spatially distributed hydrological model

    Science.gov (United States)

    Zhao, Gang; Gao, Huilin; Naz, Bibi S.; Kao, Shih-Chieh; Voisin, Nathalie

    2016-12-01

    During the past several decades, numerous reservoirs have been built across the world for a variety of purposes such as flood control, irrigation, municipal/industrial water supplies, and hydropower generation. Consequently, the timing and magnitude of natural streamflow have been altered significantly by reservoir operations. In addition, the hydrological cycle is also modified by land-use/land-cover change and by climate change. To understand the fine-scale feedback between hydrological processes and water management decisions, a distributed hydrological model embedded with a reservoir component is desired. In this study, a multi-purpose reservoir module with predefined complex operational rules was integrated into the Distributed Hydrology Soil Vegetation Model (DHSVM). Conditional operating rules, which are designed to reduce flood risk and enhance water supply reliability, were adopted in this module. The performance of the integrated model was tested over the upper Brazos River Basin in Texas, where two U.S. Army Corps of Engineers managed reservoirs, Lake Whitney and Aquilla Lake, are located. The integrated model was calibrated and validated using observed reservoir inflow, outflow, and storage data. The error statistics were summarized for both reservoirs on a daily, weekly, and monthly basis. Using the weekly reservoir storage for Lake Whitney as an example, the coefficient of determination (R2) was 0.85 and the Nash-Sutcliff Efficiency (NSE) was 0.75. These results suggest that this reservoir module holds promise for use in sub-monthly hydrological simulations. With the new reservoir component, the DHSVM provides a platform to support adaptive water resources management under the impacts of evolving anthropogenic activities and substantial environmental changes.

  15. From Eutrophic to Mesotrophic: Modelling Watershed Management Scenarios to Change the Trophic Status of a Reservoir

    Directory of Open Access Journals (Sweden)

    Marcos Mateus

    2014-03-01

    Full Text Available Management decisions related with water quality in lakes and reservoirs require a combined land-water processes study approach. This study reports on an integrated watershed-reservoir modeling methodology: the Soil and Water Assessment Tool (SWAT model to estimate the nutrient input loads from the watershed, used afterwards as boundary conditions to the reservoir model, CE-QUAL-W2. The integrated modeling system was applied to the Torrão reservoir and drainage basin. The objective of the study was to quantify the total maximum input load that allows the reservoir to be classified as mesotrophic. Torrão reservoir is located in the Tâmega River, one of the most important tributaries of the Douro River in Portugal. The watershed is characterized by a variety of land uses and urban areas, accounting for a total Waste Water Treatment Plants (WWTP discharge of ~100,000 p.e. According to the criteria defined by the National Water Institute (based on the WWTP Directive, the Torrão reservoir is classified as eutrophic. Model estimates show that a 10% reduction in nutrient loads will suffice to change the state to mesotrophic, and should target primarily WWTP effluents, but also act on diffuse sources. The method applied in this study should provide a basis for water environmental management decision-making.

  16. Characterizing regulated reservoirs dynamics in regional to global scale hydrologic models

    Science.gov (United States)

    Beighley, E.; Yoon, Y.; Lee, H.; Pavelsky, T.; Allen, G. H.

    2015-12-01

    Lakes and reservoirs are widely used for water supply and flood control resulting in regulated release of outflows that are nonconcurrent with inflows. In hydrologic modeling applications, accounting for the regulated behavior of reservoirs distributed throughout a river system poses a significant challenge because detailed reservoir operation rules or strategies can be difficult or not possible to obtain. Building on this problem, this study addresses the science questions: Can we model reservoir water storage changes and outlet discharges based on satellite measurements of river water surface elevation and inundated area, and How does repeat cycle, mission duration and measurement uncertainty impact our ability to characterize reservoir behavior? A modeling framework suitable for regional to global applications and based on the forthcoming Surface Water and Ocean Topography (SWOT) satellite mission is presented. Although our framework can be combined with data assimilation techniques for real-time flood forecasting, our goal is to represent reservoir storage patterns in large-scale hydrologic models for simulating: (i) impacts of future climate and/or land cover conditions on water resources, and (ii) synthetic storm events (e.g., 100-yr flood) or event catalogs for flood hazard and risk assessments. In-situ and remotely sensed reservoir dynamics are presented for select locations in the Mississippi River Basin and used in the Hillslope River Routing (HRR) hydrologic model to simulate downstream flow dynamics.

  17. Models for Evaluating and Improving Architecture Competence

    Science.gov (United States)

    2008-03-01

    to report on the second. We propose to use the duties from the DSK model to isolate the various aspects of the architect’s job. If we are auditing ...for Scenario Analysis.” Proceedings of the Fifth International Workshop on Product Family Engineering ( PFE -5). Sien- na, Italy, 2003, Springer

  18. Control Architecture Modeling for Future Power Systems

    DEFF Research Database (Denmark)

    Heussen, Kai

    and operation structures; and finally the application to some concrete study cases, including a present system balancing, and proposed control structures such as Microgrids and Cells. In the second part, the main contributions are the outline of a formation strategy, integrating the design and model...

  19. Molecular Simulation towards Efficient and Representative Subsurface Reservoirs Modeling

    KAUST Repository

    Kadoura, Ahmad

    2016-09-01

    This dissertation focuses on the application of Monte Carlo (MC) molecular simulation and Molecular Dynamics (MD) in modeling thermodynamics and flow of subsurface reservoir fluids. At first, MC molecular simulation is proposed as a promising method to replace correlations and equations of state in subsurface flow simulators. In order to accelerate MC simulations, a set of early rejection schemes (conservative, hybrid, and non-conservative) in addition to extrapolation methods through reweighting and reconstruction of pre-generated MC Markov chains were developed. Furthermore, an extensive study was conducted to investigate sorption and transport processes of methane, carbon dioxide, water, and their mixtures in the inorganic part of shale using both MC and MD simulations. These simulations covered a wide range of thermodynamic conditions, pore sizes, and fluid compositions shedding light on several interesting findings. For example, the possibility to have more carbon dioxide adsorbed with more preadsorbed water concentrations at relatively large basal spaces. The dissertation is divided into four chapters. The first chapter corresponds to the introductory part where a brief background about molecular simulation and motivations are given. The second chapter is devoted to discuss the theoretical aspects and methodology of the proposed MC speeding up techniques in addition to the corresponding results leading to the successful multi-scale simulation of the compressible single-phase flow scenario. In chapter 3, the results regarding our extensive study on shale gas at laboratory conditions are reported. At the fourth and last chapter, we end the dissertation with few concluding remarks highlighting the key findings and summarizing the future directions.

  20. Superstatistical model of bacterial DNA architecture

    Science.gov (United States)

    Bogachev, Mikhail I.; Markelov, Oleg A.; Kayumov, Airat R.; Bunde, Armin

    2017-02-01

    Understanding the physical principles that govern the complex DNA structural organization as well as its mechanical and thermodynamical properties is essential for the advancement in both life sciences and genetic engineering. Recently we have discovered that the complex DNA organization is explicitly reflected in the arrangement of nucleotides depicted by the universal power law tailed internucleotide interval distribution that is valid for complete genomes of various prokaryotic and eukaryotic organisms. Here we suggest a superstatistical model that represents a long DNA molecule by a series of consecutive ~150 bp DNA segments with the alternation of the local nucleotide composition between segments exhibiting long-range correlations. We show that the superstatistical model and the corresponding DNA generation algorithm explicitly reproduce the laws governing the empirical nucleotide arrangement properties of the DNA sequences for various global GC contents and optimal living temperatures. Finally, we discuss the relevance of our model in terms of the DNA mechanical properties. As an outlook, we focus on finding the DNA sequences that encode a given protein while simultaneously reproducing the nucleotide arrangement laws observed from empirical genomes, that may be of interest in the optimization of genetic engineering of long DNA molecules.

  1. System Architecture Modeling for Technology Portfolio Management using ATLAS

    Science.gov (United States)

    Thompson, Robert W.; O'Neil, Daniel A.

    2006-01-01

    Strategic planners and technology portfolio managers have traditionally relied on consensus-based tools, such as Analytical Hierarchy Process (AHP) and Quality Function Deployment (QFD) in planning the funding of technology development. While useful to a certain extent, these tools are limited in the ability to fully quantify the impact of a technology choice on system mass, system reliability, project schedule, and lifecycle cost. The Advanced Technology Lifecycle Analysis System (ATLAS) aims to provide strategic planners a decision support tool for analyzing technology selections within a Space Exploration Architecture (SEA). Using ATLAS, strategic planners can select physics-based system models from a library, configure the systems with technologies and performance parameters, and plan the deployment of a SEA. Key parameters for current and future technologies have been collected from subject-matter experts and other documented sources in the Technology Tool Box (TTB). ATLAS can be used to compare the technical feasibility and economic viability of a set of technology choices for one SEA, and compare it against another set of technology choices or another SEA. System architecture modeling in ATLAS is a multi-step process. First, the modeler defines the system level requirements. Second, the modeler identifies technologies of interest whose impact on an SEA. Third, the system modeling team creates models of architecture elements (e.g. launch vehicles, in-space transfer vehicles, crew vehicles) if they are not already in the model library. Finally, the architecture modeler develops a script for the ATLAS tool to run, and the results for comparison are generated.

  2. Software dependability modeling using an industry-standard architecture description language

    CERN Document Server

    Rugina, Ana-Elena; Kanoun, Karama; Kaaniche, Mohamed

    2008-01-01

    Performing dependability evaluation along with other analyses at architectural level allows both making architectural tradeoffs and predicting the effects of architectural decisions on the dependability of an application. This paper gives guidelines for building architectural dependability models for software systems using the AADL (Architecture Analysis and Design Language). It presents reusable modeling patterns for fault-tolerant applications and shows how the presented patterns can be used in the context of a subsystem of a real-life application.

  3. Geological Model of Member 3 of Shahejie Formation Reservoir in Liuzan Oilfield, Eastern Hebei Province

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A new geological model of Member 3 of Shahejie Formation reservoir in the Liuzan Oilfield, eastern Hebei Province was constructed by using modern reservoir modeling technology as sequence stratigraphy and conditional simulation combined with traditional geological analysis. The model consists of a stratigraphic framework model, a structural model, a sedimentary model and a reservoir model. The study shows that the reservoir is a relatively integrated nose structure, whose strata can be divided into 4 sets of parasequence, 12 parasequences. The submerged branched channel of fan delta front is the favorable microfacies, which controls the geometric shape and physical properties of reservoir sandstone. Oil is distributed in premium reservoir sandstones at structural high positions. According to the new geological model, not only the geological contradictions appearing during oil field development are resolved, but also the oil-bearing area is enlarged by 2.7km2 and geological reserves increased by 156.9 million tons. The production capacity of the Liuzan Oilfield is increased by 0.27 million tons per year.

  4. A Novel Software Simulator Model Based on Active Hybrid Architecture

    Directory of Open Access Journals (Sweden)

    Amr AbdElHamid

    2015-01-01

    Full Text Available The simulated training is an important issue for any type of missions such as aerial, ground, sea, or even space missions. In this paper, a new flexible aerial simulator based on active hybrid architecture is introduced. The simulator infrastructure is applicable to any type of training missions and research activities. This software-based simulator is tested on aerial missions to prove its applicability within time critical systems. The proposed active hybrid architecture is introduced via using the VB.NET and MATLAB in the same simulation loop. It exploits the remarkable computational power of MATLAB as a backbone aircraft model, and such mathematical model provides realistic dynamics to the trainee. Meanwhile, the Human-Machine Interface (HMI, the mission planning, the hardware interfacing, data logging, and MATLAB interfacing are developed using VB.NET. The proposed simulator is flexible enough to perform navigation and obstacle avoidance training missions. The active hybrid architecture is used during the simulated training, and also through postmission activities (like the generation of signals playback reports for evaluation purposes. The results show the ability of the proposed architecture to fulfill the aerial simulator demands and to provide a flexible infrastructure for different simulated mission requirements. Finally, a comparison with some existing simulators is introduced.

  5. The Silurian Reservoir Bed-Differentiated Asphalts in Tarim Basin and Modeling Experiments on Their Origin

    Institute of Scientific and Technical Information of China (English)

    刘洛夫; 刘宏江; 王洪玉; 曾溅辉

    2002-01-01

    There is a type of asphalt that originated from differentiation from reservoir bed (named reservoir bed-differentiated asphalt) in the Silurian asphaltic sandstones of the Tarim Basin. These asphalts are the result of second-time charging of hydrocarbons into the Silurian reservoir, which were derived from Lower Paleozoic source rocks. Asphalt was differentiated from the reservoir bed in the hydrocarbon gathering area of secondary migration. The differen tiation is caused by changes in reservoir physical properties when pearl or chain hydrocarbons migrating through and gathering in the reservoir bed, and light components are lost and heavy ones are involved in the formation of asphalt or heavy oil. There are two kinds of occurrence of these asphalts in the Silurian system of the Tarim Basin. One is the poor heavy oil layer with lower oil saturation in trap and the other is scattered hydrocarbon distributed along the transport layer and unconformity surface. Reservoir bed-differentiated asphalts have two characteristics: total hydrocarbon content is high in extractable organic matter and the ratio of saturated to aromatic hydrocarbon is usually greater than unity. The physically modeling experiment has confirmed these characteristics and the genesis of the reservoir bed-differentiated asphalts.

  6. The Silurian Reservoir Bed—Differentiated Asphalts in Tarim Basin and Modeling Experiments on Their Origin

    Institute of Scientific and Technical Information of China (English)

    刘洛夫; 刘宏江; 等

    2002-01-01

    There is a type of asphalt that originated from differentiation from reservoir bed (named reservoir bed-differentiated asphalt)in the Silurian asphaltic sandstones of the Tarim Basin.These asphalts are the result of second-time charging of hydrocarbons into the Silurian reservoir,which were derived from Lower Paleozoic source rocks.Asphalt was differentiated from the reservoir bed in the hydrocarbon gathering area of secondary migration.The different-tiation is caused by changes in reservoir physical properties when pearl or chain hydrocarbons migrating through and gathering in the reservoir bed,and light components are lost and heavy ones are involved in the formation of asphalt or heavy oil.There are two kinds of occurrence of these asphalts in the Silurian system of the Tarim Basin.One is the poor heavy oil layer with lower oil saturation in trap and the other is scattered hydrocarbon distributed along the trans-port layer and unconformity surface.Reservoir bed-differentiated asphalts have two characteris-tics:total hydrocarbon content is high in extractable organic matter and the ratio of saturated to aromatic hydrocarbon is usually greater than unity.The physically modeling experiment has confirmed these characteristics and the genesis of the reservoir bed-differentiated asphalts.

  7. The effect of lakes and reservoirs parameterization on global riverflow modeling

    Science.gov (United States)

    Zajac, Zuzanna; Hirpa, Feyera A.; Revilla-Romero, Beatriz; Salamon, Peter; Burek, Peter; Beck, Hylke E.; Thielen-del Pozo, Jutta

    2016-04-01

    Lakes and man-made reservoirs are key components of terrestrial hydrological systems. They affect flow regimes by modifying the timing and magnitude of stream flowing in and out of the water bodies, making them important physical entities in flood modeling. In this study we used 463 large lakes and 667 large reservoirs obtained from global databases to investigate their effects on daily streamflow simulations of the Global Flood Awareness System (GloFAS). GloFAS is a grid-based ensemble flood forecasting system that produces daily forecasts with a forecast horizon of 30 days. We assessed the sensitivity of the hydrological model outputs to lake and reservoir parameters using Global Sensitivity Analysis (GSA) methods. Evaluation results against observed streamflow show that incorporation of lakes resulted in improvement of model performance downstream for several catchments globally. While inclusion of reservoirs also resulted in improvement of model skill for majority of catchments, it poses more challenges due to the variability of individual reservoir's operating rules. The GSA test identified some lake and reservoir parameters as higher priority for improving the model performance. Focusing on the high priority parameters for model calibration will reduce the dimensionality without significant loss of model skill

  8. ESPC Common Model Architecture Earth System Modeling Framework (ESMF) Software and Application Development

    Science.gov (United States)

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. ESPC Common Model Architecture Earth System Modeling...LONG-TERM GOALS To expedite the development of numerical weather prediction (NWP) systems, the National Unified Operational Prediction...Capability (NUOPC) was established between NOAA and Navy to develop a common software architecture for easy and efficient interoperability. The

  9. A flexible architecture for modeling and simulation of diffusional association

    CERN Document Server

    Haack, Fiete; Uhrmacher, Adelinde M; 10.4204/EPTCS.19.5

    2010-01-01

    Up to now, it is not possible to obtain analytical solutions for complex molecular association processes (e.g. Molecule recognition in Signaling or catalysis). Instead Brownian Dynamics (BD) simulations are commonly used to estimate the rate of diffusional association, e.g. to be later used in mesoscopic simulations. Meanwhile a portfolio of diffusional association (DA) methods have been developed that exploit BD. However, DA methods do not clearly distinguish between modeling, simulation, and experiment settings. This hampers to classify and compare the existing methods with respect to, for instance model assumptions, simulation approximations or specific optimization strategies for steering the computation of trajectories. To address this deficiency we propose FADA (Flexible Architecture for Diffusional Association) - an architecture that allows the flexible definition of the experiment comprising a formal description of the model in SpacePi, different simulators, as well as validation and analysis methods....

  10. Model-based service-oriented architectures for Internetworked Enterprises

    Science.gov (United States)

    Bianchini, Devis; Brambilla, Marco; Campi, Alessandro; Cappiello, Cinzia; Ceri, Stefano; Comuzzi, Marco; de Antonellis, Valeria; Pernici, Barbara; Plebani, Pierluigi

    Service-oriented architectures (SOA) provide the basis to (re)design business processes in order to develop flexible applications where available services are dynamically composed to satisfy business goals. The adoption of this type of architecture enables the design of information systems that connect IEs to each other to run collaborative business processes. In fact, organizations can design service-based processes based either on simple internal applications or on external services. This chapter provides models and methods for the design and execution of service-based processes able to exploit all the services offered in an IEs registry. This service registry contains services that need to be defined with the same granularity and described via the same functional and non-functional models. The alignment in process and service design and modeling is discussed in this chapter, to enable the adoption of efficient techniques for service sharing, discovery and invocation.

  11. Random curds as mathematical models of fractal rhythm in architecture

    Directory of Open Access Journals (Sweden)

    Ćirović Ivana

    2014-01-01

    Full Text Available The author Carl Bovill has suggested and described a method for generating rhythm in architecture with the help of random curds, as they are the mathematical models of unpredictable and uneven groupings which he recognizes in natural shapes and in natural processes. He specified the rhythm generated in this way as the fractal rhythm. Random curds can be generated by a simple process of curdling, as suggested by B. Mandelbrot. This paper examines the way in which the choice of probability for every stage or level of the curdling process, and the number of stages in the procedure of curdling, affect the characteristics of the obtained fractal object as a potential mathematical model of rhythm in the design process. At the same time, this paper examines the characteristics of rhythm in architecture which determine whether the obtained fractal object will be accepted as an appropriate mathematical model of the observed rhythm.

  12. Modelling parallel programs and multiprocessor architectures with AXE

    Science.gov (United States)

    Yan, Jerry C.; Fineman, Charles E.

    1991-01-01

    AXE, An Experimental Environment for Parallel Systems, was designed to model and simulate for parallel systems at the process level. It provides an integrated environment for specifying computation models, multiprocessor architectures, data collection, and performance visualization. AXE is being used at NASA-Ames for developing resource management strategies, parallel problem formulation, multiprocessor architectures, and operating system issues related to the High Performance Computing and Communications Program. AXE's simple, structured user-interface enables the user to model parallel programs and machines precisely and efficiently. Its quick turn-around time keeps the user interested and productive. AXE models multicomputers. The user may easily modify various architectural parameters including the number of sites, connection topologies, and overhead for operating system activities. Parallel computations in AXE are represented as collections of autonomous computing objects known as players. Their use and behavior is described. Performance data of the multiprocessor model can be observed on a color screen. These include CPU and message routing bottlenecks, and the dynamic status of the software.

  13. Research on the Adaptive Object-Model Architecture Style

    Institute of Scientific and Technical Information of China (English)

    YAO Hai-qiong; NI Gui-qiang

    2004-01-01

    The rapidly changing requirements and business rules stimulate software developers to make their applications more dynamic, configurable, and adaptable. An effective way to meet such requirements is to apply an adaptive object-model (AOM). The AOM architecture style is composed of metamodel, model engine and tools. Firstly, two small patterns for building up metamodel are analyzed in detail. Then model engine for interpreting metamodel and tools for end-uses to define and configure object models are discussed. Finally, a novel platform-applicationware-is proposed.

  14. Modeling the groundwater recharge in karst aquifers by using a reservoir model.

    Science.gov (United States)

    Ke, Tingting; Shu, Longcang; Chen, Xunhong

    2013-01-01

    The estimation of the groundwater recharge in a karstic system becomes an important challenge due to the great hydrodynamic variability in both time and space. This paper proposes a two reservoir conceptual model to simulate inflow into both the conduit system and the fissure network system based on the analysis of the spring hydrograph. The structure of the model and the governing equations are proposed on the basis of the physical considerations, with the assumption that flow at the outlet of the reservoirs obeys a linear threshold function. The model is applied on the Houzhai karstic underground river basin where it successfully reflects the temporal recharge distribution. The simulated accumulation recharge is 34.29 mm, which is reasonable in relation to the actual rainfall of 92.8 mm. The variations of water volume in two reservoirs represent the storage and transform characteristics of the karst aquifer system. However, this model is particularly well suited to simulate the recharge event after intensive rainfall.

  15. Modeling variations of marine reservoir ages during the last 45 000 years

    Directory of Open Access Journals (Sweden)

    J. Franke

    2008-01-01

    Full Text Available When dating marine samples with 14C, the reservoir-age effect is usually assumed to be constant, although atmospheric 14C production rate and ocean circulation changes cause temporal and spatial reservoir-age variations. These lead to dating errors, which can limit the interpretation of cause and effect in paleoclimate data. We used a global ocean circulation model forced by transient atmospheric Δ14C variations to calculate reservoir ages for the last 45 000 years for a present day-like and a last glacial maximum-like ocean circulation. A ~30% reduced Atlantic meridonal overturning circulation leads to increased reservoir ages by up to ~500 years in high latitudes. Temporal variations are proportional to the absolute value of the reservoir age; regions with large reservoir age also show large variation. Temporal variations range between ~300 years in parts of the subtropics and ~1000 years in the Southern Ocean. For tropical regions, which are generally assumed to have nearly stable reservoir ages, the model suggests variations of several hundred years.

  16. Reservoir Architecture Control on the Geometry of a CO2 Plume Using 4D Seismic, Sleipner Field.

    Science.gov (United States)

    Bitrus, Roy; Iacopini, David; Bond, Clare

    2017-04-01

    Time lapse seismic from the Sleipner field, Norwegian North Sea represents a unique database to understand the geometry of a saline aquifer, the Utsira Sand Formation, and its role in containing sequestered CO2. The heterogeneous high permeability Utsira Sand formation bounded by an overlying seal is surrounded by impermeable to semi-permeable intra-reservoir thin shale units that influence the migration of injected CO2. It is important to understand and verify the dynamics of injected CO2 plume migration as this ensures close to accurate predictions of the evolving and stable state of CO2 in storage projects. Previous detailed interpretation results of the thin shale units and permeability flow path chimneys within the Utsira Formation have been used in this research. The Utsira Cap rock, IUTS1 and IUTS1 (Intra-Utsira Shale Units) are the top three units that affect the containment and upward migration path of injected CO2. They are combined with seismic geobodies of the CO2 plume across time lapse data. Here, these seismic geobodies are created using 2 methods to delineate the 3D shape and the cubic volume occupancy of the CO2 plume within the reservoir. Method 1 employs the use of an envelope attribute volume, where samples are extracted from voxels that contain seismic trace amplitude values of injected CO2 across the 3D data. These extracted samples are then tracked throughout the target area and then classed and quantified as a CO2 geobodies. Method 2 applies the same concept; the only difference is the samples extracted from voxels are classed based on the proximity and connectivity of pre-defined amplitude values. Both methods employ the use of a Bayesian classifier which defines the probability density function used to categorise the extracted threshold values. Our result of the 3D geobody shapes are compared against the internal geometry of the reservoir which shows the influence of the cap rock and intra-reservoir thin shales on the CO2 plume acting as

  17. A snow and ice melt seasonal prediction modelling system for Alpine reservoirs

    Science.gov (United States)

    Förster, Kristian; Oesterle, Felix; Hanzer, Florian; Schöber, Johannes; Huttenlau, Matthias; Strasser, Ulrich

    2016-10-01

    The timing and the volume of snow and ice melt in Alpine catchments are crucial for management operations of reservoirs and hydropower generation. Moreover, a sustainable reservoir operation through reservoir storage and flow control as part of flood risk management is important for downstream communities. Forecast systems typically provide predictions for a few days in advance. Reservoir operators would benefit if lead times could be extended in order to optimise the reservoir management. Current seasonal prediction products such as the NCEP (National Centers for Environmental Prediction) Climate Forecast System version 2 (CFSv2) enable seasonal forecasts up to nine months in advance, with of course decreasing accuracy as lead-time increases. We present a coupled seasonal prediction modelling system that runs at monthly time steps for a small catchment in the Austrian Alps (Gepatschalm). Meteorological forecasts are obtained from the CFSv2 model. Subsequently, these data are downscaled to the Alpine Water balance And Runoff Estimation model AWARE running at monthly time step. Initial conditions are obtained using the physically based, hydro-climatological snow model AMUNDSEN that predicts hourly fields of snow water equivalent and snowmelt at a regular grid with 50 m spacing. Reservoir inflow is calculated taking into account various runs of the CFSv2 model. These simulations are compared with observed inflow volumes for the melting and accumulation period 2015.

  18. Architecture on Architecture

    DEFF Research Database (Denmark)

    Olesen, Karen

    2016-01-01

    that is not scientific or academic but is more like a latent body of data that we find embedded in existing works of architecture. This information, it is argued, is not limited by the historical context of the work. It can be thought of as a virtual capacity – a reservoir of spatial configurations that can...... the obligation to prepare students to perform in a profession that is largely defined by forces outside that discipline. It will be proposed that the autonomy of architecture can be understood as a unique kind of information: as architecture’s self-reliance or knowledge-about itself. A knowledge...... be transformed and reapplied endlessly through its confrontation with shifting information from outside the realms of architecture. A selection of architects’ statements on their own work will be used to demonstrate how in quite diverse contemporary practices the re-use of existing architectures is applied...

  19. Environmental and Water Quality Operational Studies. Physical Modeling of Reservoir Hydrodynamics.

    Science.gov (United States)

    1985-12-01

    reservoir flume (re- ferred to as the General Reservoir Hydrodynamic ( GRH ) Facility) located in the Hydraulics Laboratory of WES. In this case, the GRH was...their study. 49. GRH simulation. Data from the WES Generalized Reservoir Hydrodynamic ( GRH ) Facility was used as the prototype to make the second model...prototype comparison. The GRH is 80.0 ft long and 2.85 ft wide with a maximum depth of 3.0 ft. Details of the GRH are provided in Figure 6. 44 2.85 FT

  20. An Efficient Upscaling Process Based on a Unified Fine-scale Multi-Physics Model for Flow Simulation in Naturally Fracture Carbonate Karst Reservoirs

    KAUST Repository

    Bi, Linfeng

    2009-01-01

    The main challenges in modeling fluid flow through naturally-fractured carbonate karst reservoirs are how to address various flow physics in complex geological architectures due to the presence of vugs and caves which are connected via fracture networks at multiple scales. In this paper, we present a unified multi-physics model that adapts to the complex flow regime through naturally-fractured carbonate karst reservoirs. This approach generalizes Stokes-Brinkman model (Popov et al. 2007). The fracture networks provide the essential connection between the caves in carbonate karst reservoirs. It is thus very important to resolve the flow in fracture network and the interaction between fractures and caves to better understand the complex flow behavior. The idea is to use Stokes-Brinkman model to represent flow through rock matrix, void caves as well as intermediate flows in very high permeability regions and to use an idea similar to discrete fracture network model to represent flow in fracture network. Consequently, various numerical solution strategies can be efficiently applied to greatly improve the computational efficiency in flow simulations. We have applied this unified multi-physics model as a fine-scale flow solver in scale-up computations. Both local and global scale-up are considered. It is found that global scale-up has much more accurate than local scale-up. Global scale-up requires the solution of global flow problems on fine grid, which generally is computationally expensive. The proposed model has the ability to deal with large number of fractures and caves, which facilitate the application of Stokes-Brinkman model in global scale-up computation. The proposed model flexibly adapts to the different flow physics in naturally-fractured carbonate karst reservoirs in a simple and effective way. It certainly extends modeling and predicting capability in efficient development of this important type of reservoir.

  1. Modeling of Salinity Effects on Waterflooding of Petroleum Reservoirs

    DEFF Research Database (Denmark)

    Alexeev, Artem

    of the experimental studies concerning the smart water effects recognize importance of the chemistry of reservoir rocks that manifests itself in dissolution and precipitation of rock minerals and adsorption of specific ions on the rock surface. The brine-rock interactions may affect the wetting state of the rock...... brine and the formation water that is initially in equilibrium with the reservoir rock. We consider a displacement process in one dimension with dissolution affecting both the porosity/permeability of the rock and the density of the brine. Extending previous studies, we account for the different...... of residual oil and its flow in porous media. The oil trapped in the swept zones after conventional flooding is present in a form of disconnected oil drops, or oil ganglia. While the macroscopic theory of multiphase flow assumes that fluid phases flow in their own pore networks and do not influence each other...

  2. Columnar architecture improves noise robustness in a model cortical network.

    Directory of Open Access Journals (Sweden)

    Paul C Bush

    Full Text Available Cortical columnar architecture was discovered decades ago yet there is no agreed upon explanation for its function. Indeed, some have suggested that it has no function, it is simply an epiphenomenon of developmental processes. To investigate this problem we have constructed a computer model of one square millimeter of layer 2/3 of the primary visual cortex (V1 of the cat. Model cells are connected according to data from recent paired cell studies, in particular the connection probability between pyramidal cells is inversely proportional both to the distance separating the cells and to the distance between the preferred parameters (features of the cells. We find that these constraints, together with a columnar architecture, produce more tightly clustered populations of cells when compared to the random architecture seen in, for example, rodents. This causes the columnar network to converge more quickly and accurately on the pattern representing a particular stimulus in the presence of noise, suggesting that columnar connectivity functions to improve pattern recognition in cortical circuits. The model also suggests that synaptic failure, a phenomenon exhibited by weak synapses, may conserve metabolic resources by reducing transmitter release at these connections that do not contribute to network function.

  3. From Principles to Details: Integrated Framework for Architecture Modelling of Large Scale Software Systems

    Directory of Open Access Journals (Sweden)

    Andrzej Zalewski

    2013-06-01

    Full Text Available There exist numerous models of software architecture (box models, ADL’s, UML, architectural decisions, architecture modelling frameworks (views, enterprise architecture frameworks and even standards recommending practice for the architectural description. We show in this paper, that there is still a gap between these rather abstract frameworks/standards and existing architecture models. Frameworks and standards define what should be modelled rather than which models should be used and how these models are related to each other. We intend to prove that a less abstract modelling framework is needed for the effective modelling of large scale software intensive systems. It should provide a more precise guidance kinds of models to be employed and how they should relate to each other. The paper defines principles that can serve as base for an integrated model. Finally, structure of such a model has been proposed. It comprises three layers: the upper one – architectural policy – reflects corporate policy and strategies in architectural terms, the middle one –system organisation pattern – represents the core structural concepts and their rationale at a given level of scope, the lower one contains detailed architecture models. Architectural decisions play an important role here: they model the core architectural concepts explaining detailed models as well as organise the entire integrated model and the relations between its submodels.

  4. Biogeochemical mass balances in a turbid tropical reservoir. Field data and modelling approach

    Science.gov (United States)

    Phuong Doan, Thuy Kim; Némery, Julien; Gratiot, Nicolas; Schmid, Martin

    2014-05-01

    The turbid tropical Cointzio reservoir, located in the Trans Mexican Volcanic Belt (TMVB), behaves as a warm monomictic water body (area = 6 km2, capacity 66 Mm3, residence time ~ 1 year). It is strategic for the drinking water supply of the city of Morelia, capital of the state of Michoacán, and for downstream irrigation during the dry season. This reservoir is a perfect example of a human-impacted system since its watershed is mainly composed of degraded volcanic soils and is subjected to high erosion processes and agricultural loss. The reservoir is threatened by sediment accumulation and nutrients originating from untreated waters in the upstream watershed. The high content of very fine clay particles and the lack of water treatment plants lead to serious episodes of eutrophication (up to 70 μg chl. a L-1), high levels of turbidity (Secchi depth water vertical profiles, reservoir inflow and outflow) we determined suspended sediment (SS), carbon (C), nitrogen (N) and phosphorus (P) mass balances. Watershed SS yields were estimated at 35 t km2 y-1 of which 89-92 % were trapped in the Cointzio reservoir. As a consequence the reservoir has already lost 25 % of its initial storage capacity since its construction in 1940. Nutrient mass balances showed that 50 % and 46 % of incoming P and N were retained by sedimentation, and mainly eliminated through denitrification respectively. Removal of C by 30 % was also observed both by sedimentation and through gas emission. To complete field data analyses we examined the ability of vertical one dimensional (1DV) numerical models (Aquasim biogeochemical model coupled with k-ɛ mixing model) to reproduce the main biogeochemical cycles in the Cointzio reservoir. The model can describe all the mineralization processes both in the water column and in the sediment. The values of the entire mass balance of nutrients and of the mineralization rates (denitrification and aerobic benthic mineralization) calculated from the model

  5. The Architectural Designs of a Nanoscale Computing Model

    Directory of Open Access Journals (Sweden)

    Mary M. Eshaghian-Wilner

    2004-08-01

    Full Text Available A generic nanoscale computing model is presented in this paper. The model consists of a collection of fully interconnected nanoscale computing modules, where each module is a cube of cells made out of quantum dots, spins, or molecules. The cells dynamically switch between two states by quantum interactions among their neighbors in all three dimensions. This paper includes a brief introduction to the field of nanotechnology from a computing point of view and presents a set of preliminary architectural designs for fabricating the nanoscale model studied.

  6. The Architectural Designs of a Nanoscale Computing Model

    Directory of Open Access Journals (Sweden)

    Mary M. Eshaghian-Wilner

    2004-08-01

    Full Text Available A generic nanoscale computing model is presented in this paper. The model consists of a collection of fully interconnected nanoscale computing modules, where each module is a cube of cells made out of quantum dots, spins, or molecules. The cells dynamically switch between two states by quantum interactions among their neighbors in all three dimensions. This paper includes a brief introduction to the field of nanotechnology from a computing point of view and presents a set of preliminary architectural designs for fabricating the nanoscale model studied.

  7. Development and evaluation of a reservoir model for the Chain of Lakes in Illinois

    Science.gov (United States)

    Domanski, Marian M.

    2017-01-27

    Forecasts of flows entering and leaving the Chain of Lakes reservoir on the Fox River in northeastern Illinois are critical information to water-resource managers who determine the optimal operation of the dam at McHenry, Illinois, to help minimize damages to property and loss of life because of flooding on the Fox River. In 2014, the U.S. Geological Survey; the Illinois Department of Natural Resources, Office of Water Resources; and National Weather Service, North Central River Forecast Center began a cooperative study to develop a system to enable engineers and planners to simulate and communicate flows and to prepare proactively for precipitation events in near real time in the upper Fox River watershed. The purpose of this report is to document the development and evaluation of the Chain of Lakes reservoir model developed in this study.The reservoir model for the Chain of Lakes was developed using the Hydrologic Engineering Center–Reservoir System Simulation program. Because of the complex relation between the dam headwater and reservoir pool elevations, the reservoir model uses a linear regression model that relates dam headwater elevation to reservoir pool elevation. The linear regression model was developed using 17 U.S. Geological Survey streamflow measurements, along with the gage height in the reservoir pool and the gage height at the dam headwater. The Nash-Sutcliffe model efficiency coefficients for all three linear regression model variables ranged from 0.90 to 0.98.The reservoir model performance was evaluated by graphically comparing simulated and observed reservoir pool elevation time series during nine periods of high pool elevation. In addition, the peak elevations during these time periods were graphically compared to the closest-in-time observed pool elevation peak. The mean difference in the simulated and observed peak elevations was -0.03 feet, with a standard deviation of 0.19 feet. The Nash-Sutcliffe coefficient for peak prediction was

  8. Integrated reservoir characterization: Improvement in heterogeneities stochastic modelling by integration of additional external constraints

    Energy Technology Data Exchange (ETDEWEB)

    Doligez, B.; Eschard, R. [Institut Francais du Petrole, Rueil Malmaison (France); Geffroy, F. [Centre de Geostatistique, Fontainebleau (France)] [and others

    1997-08-01

    The classical approach to construct reservoir models is to start with a fine scale geological model which is informed with petrophysical properties. Then scaling-up techniques allow to obtain a reservoir model which is compatible with the fluid flow simulators. Geostatistical modelling techniques are widely used to build the geological models before scaling-up. These methods provide equiprobable images of the area under investigation, which honor the well data, and which variability is the same than the variability computed from the data. At an appraisal phase, when few data are available, or when the wells are insufficient to describe all the heterogeneities and the behavior of the field, additional constraints are needed to obtain a more realistic geological model. For example, seismic data or stratigraphic models can provide average reservoir information with an excellent areal coverage, but with a poor vertical resolution. New advances in modelisation techniques allow now to integrate this type of additional external information in order to constrain the simulations. In particular, 2D or 3D seismic derived information grids, or sand-shale ratios maps coming from stratigraphic models can be used as external drifts to compute the geological image of the reservoir at the fine scale. Examples are presented to illustrate the use of these new tools, their impact on the final reservoir model, and their sensitivity to some key parameters.

  9. Modeling white sturgeon movement in a reservoir: The effect of water quality and sturgeon density

    Science.gov (United States)

    Sullivan, A.B.; Jager, H.I.; Myers, R.

    2003-01-01

    We developed a movement model to examine the distribution and survival of white sturgeon (Acipenser transmontanus) in a reservoir subject to large spatial and temporal variation in dissolved oxygen and temperature. Temperature and dissolved oxygen were simulated by a CE-QUAL-W2 model of Brownlee Reservoir, Idaho for a typical wet, normal, and dry hydrologic year. We compared current water quality conditions to scenarios with reduced nutrient inputs to the reservoir. White sturgeon habitat quality was modeled as a function of temperature, dissolved oxygen and, in some cases, suitability for foraging and depth. We assigned a quality index to each cell along the bottom of the reservoir. The model simulated two aspects of daily movement. Advective movement simulated the tendency for animals to move toward areas with high habitat quality, and diffusion simulated density dependent movement away from areas with high sturgeon density in areas with non-lethal habitat conditions. Mortality resulted when sturgeon were unable to leave areas with lethal temperature or dissolved oxygen conditions. Water quality was highest in winter and early spring and lowest in mid to late summer. Limiting nutrient inputs reduced the area of Brownlee Reservoir with lethal conditions for sturgeon and raised the average habitat suitability throughout the reservoir. Without movement, simulated white sturgeon survival ranged between 45 and 89%. Allowing movement raised the predicted survival of sturgeon under all conditions to above 90% as sturgeon avoided areas with low habitat quality. ?? 2003 Elsevier B.V. All rights reserved.

  10. Analytical Modeling and Contradictions in Limestone Reservoirs: Breccias, Vugs, and Fractures

    Directory of Open Access Journals (Sweden)

    Nelson Barros-Galvis

    2015-01-01

    Full Text Available Modeling of limestone reservoirs is traditionally developed applying tectonic fractures concepts or planar discontinuities and has been simulated dynamically without considering nonplanar discontinuities as sedimentary breccias, vugs, fault breccias, and impact breccias, assuming that all these nonplanar discontinuities are tectonic fractures, causing confusion and contradictions in reservoirs characterization. The differences in geometry and connectivity in each discontinuity affect fluid flow, generating the challenge to develop specific analytical models that describe quantitatively hydrodynamic behavior in breccias, vugs, and fractures, focusing on oil flow in limestone reservoirs. This paper demonstrates the differences between types of discontinuities that affect limestone reservoirs and recommends that all discontinuities should be included in simulation and static-dynamic characterization, because they impact fluid flow. To demonstrate these differences, different analytic models are developed. Findings of this work are based on observations of cores, outcrops, and tomography and are validated with field data. The explanations and mathematical modeling developed here could be used as diagnostic tools to predict fluid velocity and fluid flow in limestone reservoirs, improving the complex reservoirs static-dynamic characterization.

  11. Sediment Deposition Risk Analysis and PLSR Model Research for Cascade Reservoirs Upstream of the Yellow River

    Directory of Open Access Journals (Sweden)

    Jie Yang

    2015-01-01

    Full Text Available It is difficult to effectively identify and eliminate the multiple correlation influence among the independent factors by least-squares regression. Focusing on this insufficiency, the sediment deposition risk of cascade reservoirs and fitting model of sediment flux into the reservoir are studied. The partial least-squares regression (PLSR method is adopted for modeling analysis; the model fitting is organically combined with the non-model-style data content analysis, so as to realize the regression model, data structure simplification, and multiple correlations analysis among factors; meanwhile the accuracy of the model is ensured through cross validity check. The modeling analysis of sediment flux into the cascade reservoirs of Long-Liu section upstream of the Yellow River indicates that partial least-squares regression can effectively overcome the multiple correlation influence among factors, and the isolated factor variables have better ability to explain the physical cause of measured results.

  12. Optimal Reservoir Operation for Hydropower Generation using Non-linear Programming Model

    Science.gov (United States)

    Arunkumar, R.; Jothiprakash, V.

    2012-05-01

    Hydropower generation is one of the vital components of reservoir operation, especially for a large multi-purpose reservoir. Deriving optimal operational rules for such a large multi-purpose reservoir serving various purposes like irrigation, hydropower and flood control are complex, because of the large dimension of the problem and the complexity is more if the hydropower production is not an incidental. Thus optimizing the operations of a reservoir serving various purposes requires a systematic study. In the present study such a large multi-purpose reservoir, namely, Koyna reservoir operations are optimized for maximizing the hydropower production subject to the condition of satisfying the irrigation demands using a non-linear programming model. The hydropower production from the reservoir is analysed for three different dependable inflow conditions, representing wet, normal and dry years. For each dependable inflow conditions, various scenarios have been analyzed based on the constraints on the releases and the results are compared. The annual power production, combined monthly power production from all the powerhouses, end of month storage levels, evaporation losses and surplus are discussed. From different scenarios, it is observed that more hydropower can be generated for various dependable inflow conditions, if the restrictions on releases are slightly relaxed. The study shows that Koyna dam is having potential to generate more hydropower.

  13. Stochastic reservoir simulation for the modeling of uncertainty in coal seam degasification

    Science.gov (United States)

    Karacan, C. Özgen; Olea, Ricardo A.

    2015-01-01

    Coal seam degasification improves coal mine safety by reducing the gas content of coal seams and also by generating added value as an energy source. Coal seam reservoir simulation is one of the most effective ways to help with these two main objectives. As in all modeling and simulation studies, how the reservoir is defined and whether observed productions can be predicted are important considerations.

  14. California Reservoir Drought Sensitivity and Exhaustion Risk Using Statistical Graphical Models

    OpenAIRE

    Taeb, Armeen; Reager, John T.; Turmon, Michael; Chandrasekaran, Venkat

    2016-01-01

    The ongoing California drought has highlighted the potential vulnerability of state water management infrastructure to multi-year dry intervals. Due to the high complexity of the network, dynamic storage changes across the California reservoir system have been difficult to model using either conventional statistical or physical approaches. Here, we analyze the interactions of monthly volumes in a network of 55 large California reservoirs, over a period of 136 months from 2004 to 2015, and we ...

  15. Depositional sequence analysis and sedimentologic modeling for improved prediction of Pennsylvanian reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Watney, W.L.

    1994-12-01

    Reservoirs in the Lansing-Kansas City limestone result from complex interactions among paleotopography (deposition, concurrent structural deformation), sea level, and diagenesis. Analysis of reservoirs and surface and near-surface analogs has led to developing a {open_quotes}strandline grainstone model{close_quotes} in which relative sea-level stabilized during regressions, resulting in accumulation of multiple grainstone buildups along depositional strike. Resulting stratigraphy in these carbonate units are generally predictable correlating to inferred topographic elevation along the shelf. This model is a valuable predictive tool for (1) locating favorable reservoirs for exploration, and (2) anticipating internal properties of the reservoir for field development. Reservoirs in the Lansing-Kansas City limestones are developed in both oolitic and bioclastic grainstones, however, re-analysis of oomoldic reservoirs provides the greatest opportunity for developing bypassed oil. A new technique, the {open_quotes}Super{close_quotes} Pickett crossplot (formation resistivity vs. porosity) and its use in an integrated petrophysical characterization, has been developed to evaluate extractable oil remaining in these reservoirs. The manual method in combination with 3-D visualization and modeling can help to target production limiting heterogeneities in these complex reservoirs and moreover compute critical parameters for the field such as bulk volume water. Application of this technique indicates that from 6-9 million barrels of Lansing-Kansas City oil remain behind pipe in the Victory-Northeast Lemon Fields. Petroleum geologists are challenged to quantify inferred processes to aid in developing rationale geologically consistent models of sedimentation so that acceptable levels of prediction can be obtained.

  16. Modeling Water-Quality Loads to the Reservoirs of the Upper Trinity River Basin, Texas, USA

    OpenAIRE

    Taesoo Lee; Xiuying Wang; Michael White; Pushpa Tuppad; Raghavan Srinivasan; Balaji Narasimhan; Darrel Andrews

    2015-01-01

    The Upper Trinity River Basin (TRB) is the most populated river basin and one of the largest water suppliers in Texas. However, sediment and nutrient loads are reducing the capacity of reservoirs and degrading water quality. The objectives of this study are to calibrate and validate the Soil and Water Assessment Tool (SWAT) model for ten study watersheds within the Upper TRB in order to assess nutrient loads into major reservoirs in the basin and to predict the effects of point source elimina...

  17. Experimental model for architectural systematization and its basic thermal performance. Part 1. Research on architectural systematization of energy conversion devices; Kenchiku system ka model no gaiyo to kihon seino ni tsuite. 1. Energy henkan no kenchiku system ka ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Sunaga, N.; Ito, N.; Kimura, G.; Fukao, S.; Shimizu, T.; Tsunoda, M.; Muro, K. [Tokyo Metropolitan University, Tokyo (Japan)

    1996-10-27

    The outline of a model for architectural systematization of natural energy conversion and the experiment result on the basic thermal performance in winter are described. The model is about 20 m{sup 2} in floor space. Foam polystyrene of 100 mm and 200 mm thick was used for the outer wall as heat insulating materials. The model has a solar battery and air conditioner and uses red brick as a heat reservoir. An experiment was made on seven modes obtained when three elements (heating, heat storage, and night insulated door) are combined. The information obtained by the experiment showed that a model for architectural systematization has high heat insulation and tightness and can be used as an energy element or an evaluation model for architectural systematization. In this model for architectural systematization, the power consumption of an air conditioner in winter can be fully supplied by only the power generation based on a solar battery. In an architectural element, the heating energy consumption can be remarkably reduced and the indoor thermal environment can be greatly improved, by the combination of a heat reservoir and night heat insulated door. 1 ref., 6 figs., 3 tabs.

  18. Velocity Modeling and Inversion Techniques for Locating Microseismic Events in Unconventional Reservoirs

    Institute of Scientific and Technical Information of China (English)

    Jianzhong Zhang; Han Liu; Zhihui Zou; Zhonglai Huang

    2015-01-01

    A velocity model is an important factor influencing microseismic event locations. We re-view the velocity modeling and inversion techniques for locating microseismic events in exploration for unconventional oil and gas reservoirs. We first describe the geological and geophysical characteristics of reservoir formations related to hydraulic fracturing in heterogeneity, anisotropy, and variability, then discuss the influences of velocity estimation, anisotropy model, and their time-lapse changes on the accuracy in determining microseismic event locations, and then survey some typical methods for build-ing velocity models in locating event locations. We conclude that the three tangled physical attributes of reservoirs make microseismic monitoring very challenging. The uncertainties in velocity model and ig-noring its anisotropies and its variations in hydraulic fracturing can cause systematic mislocations of microseismic events which are unacceptable in microseismic monitoring. So, we propose some potential ways for building accurate velocity models.

  19. Energy consumption model over parallel programs implemented on multicore architectures

    Directory of Open Access Journals (Sweden)

    Ricardo Isidro-Ramirez

    2015-06-01

    Full Text Available In High Performance Computing, energy consump-tion is becoming an important aspect to consider. Due to the high costs that represent energy production in all countries it holds an important role and it seek to find ways to save energy. It is reflected in some efforts to reduce the energy requirements of hardware components and applications. Some options have been appearing in order to scale down energy use and, con-sequently, scale up energy efficiency. One of these strategies is the multithread programming paradigm, whose purpose is to produce parallel programs able to use the full amount of computing resources available in a microprocessor. That energy saving strategy focuses on efficient use of multicore processors that are found in various computing devices, like mobile devices. Actually, as a growing trend, multicore processors are found as part of various specific purpose computers since 2003, from High Performance Computing servers to mobile devices. However, it is not clear how multiprogramming affects energy efficiency. This paper presents an analysis of different types of multicore-based architectures used in computing, and then a valid model is presented. Based on Amdahl’s Law, a model that considers different scenarios of energy use in multicore architectures it is proposed. Some interesting results were found from experiments with the developed algorithm, that it was execute of a parallel and sequential way. A lower limit of energy consumption was found in a type of multicore architecture and this behavior was observed experimentally.

  20. Brittleness index and seismic rock physics model for anisotropic tight-oil sandstone reservoirs

    Institute of Scientific and Technical Information of China (English)

    Huang Xin-Rui; Huang Jian-Ping; Li Zhen-Chun; Yang Qin-Yong; Sun Qi-Xing; Cui Wei

    2015-01-01

    Brittleness analysis becomes important when looking for sweet spots in tight-oil sandstone reservoirs. Hence, appropriate indices are required as accurate brittleness evaluation criteria. We construct a seismic rock physics model for tight-oil sandstone reservoirs with vertical fractures. Because of the complexities in lithology and pore structure and the anisotropic characteristics of tight-oil sandstone reservoirs, the proposed model is based on the solid components, pore connectivity, pore type, and fractures to better describe the sandstone reservoir microstructure. Using the model, we analyze the brittleness sensitivity of the elastic parameters in an anisotropic medium and establish a new brittleness index. We show the applicability of the proposed brittleness index for tight-oil sandstone reservoirs by considering the brittleness sensitivity, the rock physics response characteristics, and cross-plots. Compared with conventional brittleness indexes, the new brittleness index has high brittleness sensitivity and it is the highest in oil-bearing brittle zones with relatively high porosity. The results also suggest that the new brittleness index is much more sensitive to elastic properties variations, and thus can presumably better predict the brittleness characteristics of sweet spots in tight-oil sandstone reservoirs.

  1. Managing changes in the enterprise architecture modelling context

    Science.gov (United States)

    Khanh Dam, Hoa; Lê, Lam-Son; Ghose, Aditya

    2016-07-01

    Enterprise architecture (EA) models the whole enterprise in various aspects regarding both business processes and information technology resources. As the organisation grows, the architecture of its systems and processes must also evolve to meet the demands of the business environment. Evolving an EA model may involve making changes to various components across different levels of the EA. As a result, an important issue before making a change to an EA model is assessing the ripple effect of the change, i.e. change impact analysis. Another critical issue is change propagation: given a set of primary changes that have been made to the EA model, what additional secondary changes are needed to maintain consistency across multiple levels of the EA. There has been however limited work on supporting the maintenance and evolution of EA models. This article proposes an EA description language, namely ChangeAwareHierarchicalEA, integrated with an evolution framework to support both change impact analysis and change propagation within an EA model. The core part of our framework is a technique for computing the impact of a change and a new method for generating interactive repair plans from Alloy consistency rules that constrain the EA model.

  2. Models and prototypes of biomimetic devices to architectural purposes

    Directory of Open Access Journals (Sweden)

    Silvia Titotto

    2014-12-01

    Full Text Available This paper presents some results of an ongoing interdisciplinary research about models and prototypes of biomimetic devices via installations and the focus of this paper is to outline this research role in architectural purposes as it perpasses the cultural and heritage contexts by being a way of understanding and living in the world as well as taking place in the world as devices or environments that pass on to future generations to use, learn from and be inspired by. Both the theoretical and the experimental work done so far point out that installations built with association of laser cutting and rapid prototyping techniques might be on the best feasible ways for developing and testing new technologies involved in biomimetic devices to architectural purposes that put both tectonics and nature as their central theme. 

  3. Incorporating teleconnection information into reservoir operating policies using Stochastic Dynamic Programming and a Hidden Markov Model

    Science.gov (United States)

    Turner, Sean; Galelli, Stefano; Wilcox, Karen

    2015-04-01

    Water reservoir systems are often affected by recurring large-scale ocean-atmospheric anomalies, known as teleconnections, that cause prolonged periods of climatological drought. Accurate forecasts of these events -- at lead times in the order of weeks and months -- may enable reservoir operators to take more effective release decisions to improve the performance of their systems. In practice this might mean a more reliable water supply system, a more profitable hydropower plant or a more sustainable environmental release policy. To this end, climate indices, which represent the oscillation of the ocean-atmospheric system, might be gainfully employed within reservoir operating models that adapt the reservoir operation as a function of the climate condition. This study develops a Stochastic Dynamic Programming (SDP) approach that can incorporate climate indices using a Hidden Markov Model. The model simulates the climatic regime as a hidden state following a Markov chain, with the state transitions driven by variation in climatic indices, such as the Southern Oscillation Index. Time series analysis of recorded streamflow data reveals the parameters of separate autoregressive models that describe the inflow to the reservoir under three representative climate states ("normal", "wet", "dry"). These models then define inflow transition probabilities for use in a classic SDP approach. The key advantage of the Hidden Markov Model is that it allows conditioning the operating policy not only on the reservoir storage and the antecedent inflow, but also on the climate condition, thus potentially allowing adaptability to a broader range of climate conditions. In practice, the reservoir operator would effect a water release tailored to a specific climate state based on available teleconnection data and forecasts. The approach is demonstrated on the operation of a realistic, stylised water reservoir with carry-over capacity in South-East Australia. Here teleconnections relating

  4. Recreation of architectural structures using procedural modeling based on volumes

    Directory of Open Access Journals (Sweden)

    Santiago Barroso Juan

    2013-11-01

    Full Text Available While the procedural modeling of buildings and other architectural structures has evolved very significantly in recent years, there is noticeable absence of high-level tools that allow a designer, an artist or an historian, creating important buildings or architectonic structures in a particular city. In this paper we present a tool for creating buildings in a simple and clear, following rules that use the language and methodology of creating their own buildings, and hiding the user the algorithmic details of the creation of the model.

  5. SpaceWire model development technology for satellite architecture.

    Energy Technology Data Exchange (ETDEWEB)

    Eldridge, John M.; Leemaster, Jacob Edward; Van Leeuwen, Brian P.

    2011-09-01

    Packet switched data communications networks that use distributed processing architectures have the potential to simplify the design and development of new, increasingly more sophisticated satellite payloads. In addition, the use of reconfigurable logic may reduce the amount of redundant hardware required in space-based applications without sacrificing reliability. These concepts were studied using software modeling and simulation, and the results are presented in this report. Models of the commercially available, packet switched data interconnect SpaceWire protocol were developed and used to create network simulations of data networks containing reconfigurable logic with traffic flows for timing system distribution.

  6. Hypermedia Genes An Evolutionary Perspective on Concepts, Models, and Architectures

    CERN Document Server

    Guimarães, Nuno

    2009-01-01

    The design space of information services evolved from seminal works through a set of prototypical hypermedia systems and matured in open and widely accessible web-based systems. The original concepts of hypermedia systems are now expressed in different forms and shapes. The first works on hypertext invented the term itself, laid out the foundational concept of association or link, and highlighted navigation as the core paradigm for the future information systems. The first engineered systems demonstrated architectural requirements and models and fostered the emergence of the conceptual model r

  7. 尼日尔三角洲盆地Akpo油田新近系深水浊积水道储层构型表征%Characterization of reservoir architectures for Neogene deepwater turbidity channels of Akpo oilfield, Niger Delta Basin

    Institute of Scientific and Technical Information of China (English)

    赵晓明; 吴胜和; 刘丽

    2012-01-01

    由于深水浊积水道油藏多位于深海区,受作业成本的限制,其开发井距往往较大,利用现行的针对密井网区的多井模式拟合方法进行该类油藏的地下储层构型表征,其精度较低.为此,利用西非尼日尔三角洲盆地深水区Akpo油田稀井条件下的钻井与地震资料,提出了基于井-震联合的该区深水浊积水道储层构型表征技术,论述了其表征思路与方法.深水浊积水道储层构型可分为水道体系、复合水道和单一水道3个层次,其中复合水道层次又可细分为复合水道系列和复合水道2个亚层次,不同层次构型单元规模差异大,需要在构型模式指导下,分别开展基于油组、小层及小层内部切片的井-震联合,将不同层次的构型模式与钻井、地震资料进行拟合,完成深水浊积水道的储层构型表征.这一研究不仅对高效开发深水浊积水道油藏具有实用价值,对利用井-震联合方法开展储层构型研究也具有重要参考价值.%Deepwater turbidity channel reservoirs are usually located in deep sea areas, where a distant spacing pattern for development wells is often allocated due to the cost constraint of prospecting operation. Consequently, the characterization of such underground reservoir architectures of deepwater turbidity channels with the current overlay method for multi-well models used mainly under dense-well pattern conditions usually achieves a poor precision. Therefore, based on drilling and seismic data of a distant well spacing pattern for deepwater turbidity channel reservoirs of the Akpo oilfield in Niger Delta Basin, West Africa, we introduced a novel method to characterize such turbidity channel reservoir architectures in terms of well-to-seismic integration, and discussed its conception and procedures as well. Reservoir architectures of deepwater turbidity channels can be classified into three orders, channel system, channel complex and single channel. Of

  8. A stochastic conflict resolution model for water quality management in reservoir river systems

    Science.gov (United States)

    Kerachian, Reza; Karamouz, Mohammad

    2007-04-01

    In this paper, optimal operating rules for water quality management in reservoir-river systems are developed using a methodology combining a water quality simulation model and a stochastic GA-based conflict resolution technique. As different decision-makers and stakeholders are involved in the water quality management in reservoir-river systems, a new stochastic form of the Nash bargaining theory is used to resolve the existing conflict of interests related to water supply to different demands, allocated water quality and waste load allocation in downstream river. The expected value of the Nash product is considered as the objective function of the model which can incorporate the inherent uncertainty of reservoir inflow. A water quality simulation model is also developed to simulate the thermal stratification cycle in the reservoir, the quality of releases from different outlets as well as the temporal and spatial variation of the pollutants in the downstream river. In this study, a Varying Chromosome Length Genetic Algorithm (VLGA), which has computational advantages comparing to other alternative models, is used. VLGA provides a good initial solution for Simple Genetic Algorithms and comparing to Stochastic Dynamic Programming (SDP) reduces the number of state transitions checked in each stage. The proposed model, which is called Stochastic Varying Chromosome Length Genetic Algorithm with water Quality constraints (SVLGAQ), is applied to the Ghomrud Reservoir-River system in the central part of Iran. The results show, the proposed model for reservoir operation and waste load allocation can reduce the salinity of the allocated water demands as well as the salinity build-up in the reservoir.

  9. Effects of gas types and models on optimized gas fuelling station reservoir's pressure

    Directory of Open Access Journals (Sweden)

    M. Farzaneh-Gord

    2013-06-01

    Full Text Available There are similar algorithms and infrastructure for storing gas fuels at CNG (Compressed Natural Gas and CHG (Compressed Hydrogen Gas fuelling stations. In these stations, the fuels are usually stored in the cascade storage system to utilize the stations more efficiently. The cascade storage system generally divides into three reservoirs, commonly termed low, medium and high-pressure reservoirs. The pressures within these reservoirs have huge effects on performance of the stations. In the current study, based on the laws of thermodynamics, conservation of mass and real/ideal gas assumptions, a theoretical analysis has been constructed to study the effects of gas types and models on performance of the stations. It is intended to determine the optimized reservoir pressures for these stations. The results reveal that the optimized pressure differs between the gas types. For ideal and real gas models in both stations (CNG and CHG, the optimized non-dimensional low pressure-reservoir pressure is found to be 0.22. The optimized non-dimensional medium-pressure reservoir pressure is the same for the stations, and equal to 0.58.

  10. Generic Architecture for Cloud Infrastructure as a Service (IaaS) Provisioning Model

    NARCIS (Netherlands)

    Demchenko, Y.; Ham, J. van der; Strijkers, R.J.; Ghijsen, M.; Ngo, C.; Cristea, M.

    2011-01-01

    This document provides information about the proposed architectural framework for Cloud Infrastructure as a Service (IaaS) provisioning model that includes the following components: the Composable Services Architecture (CSA) that intends to provide a conceptual and methodological framework for

  11. Towards effective modeling and programming multi-core tiled reconfigurable architectures

    NARCIS (Netherlands)

    Rovers, K.C.; Burgwal, van de M.D.; Kuper, J.; Smit, G.J.M.

    2009-01-01

    For a generic flexible efficient array antenna receiver platform a hierarchical reconfigurable tiled architecture has been proposed. The architecture provides a flexible reconfigurable solution, but partitioning, mapping, modeling and programming such systems remains an issue. We will advocate a mod

  12. Seismic monitoring of heavy oil reservoirs: Rock physics and finite element modelling

    Science.gov (United States)

    Theune, Ulrich

    In the past decades, remote monitoring of subsurface processes has attracted increasing attention in geophysics. With repeated geophysical surveys one attempts to detect changes in the physical properties in the underground without directly accessing the earth. This technique has been proven to be very valuable for monitoring enhanced oil recovery programs. This thesis presents an modelling approach for the feasibility analysis for monitoring of a thermal enhanced oil recovery technique applied to heavy oil reservoirs in the Western Canadian Sedimentary Basin. In order to produce heavy oil from shallow reservoirs thermal oil recovery techniques such as the Steam Assisted Gravity Drainage (SAGD) are often employed. As these techniques are expensive and technically challenging, early detection of operational problems is without doubt of great value. However, the feasibility of geophysical monitoring depends on many factors such as the changes in the rock physical properties of the target reservoir. In order to access the feasibility of seismic monitoring for heavy oil reservoirs, a fluid-substitutional rock physical study has been carried out to simulate the steam injection. The second modelling approach is based on a modified finite element algorithm to simulate the propagation of elastic waves in the earth, which has been developed independently in the framework of this thesis. The work summarized in this thesis shows a possibility to access the feasibility of seismic monitoring for heavy oil reservoirs through an extensive rock-physical study. Seismic monitoring is a useful tool in reservoir management decision process. However, the work reported here suggests that seismic monitoring of SAGD processes in the heavy oil reservoirs of the Western Canadian Sedimentary Basin is only feasible in shallow, unconsolidated deposits. For deeper, but otherwise geological similar reservoirs, the SAGD does not create a sufficient change in the rock physical properties to be

  13. A Step Forward to Closing the Loop between Static and Dynamic Reservoir Modeling

    Directory of Open Access Journals (Sweden)

    Cancelliere M.

    2014-12-01

    Full Text Available The current trend for history matching is to find multiple calibrated models instead of a single set of model parameters that match the historical data. The advantage of several current workflows involving assisted history matching techniques, particularly those based on heuristic optimizers or direct search, is that they lead to a number of calibrated models that partially address the problem of the non-uniqueness of the solutions. The importance of achieving multiple solutions is that calibrated models can be used for a true quantification of the uncertainty affecting the production forecasts, which represent the basis for technical and economic risk analysis. In this paper, the importance of incorporating the geological uncertainties in a reservoir study is demonstrated. A workflow, which includes the analysis of the uncertainty associated with the facies distribution for a fluvial depositional environment in the calibration of the numerical dynamic models and, consequently, in the production forecast, is presented. The first step in the workflow was to generate a set of facies realizations starting from different conceptual models. After facies modeling, the petrophysical properties were assigned to the simulation domains. Then, each facies realization was calibrated separately by varying permeability and porosity fields. Data assimilation techniques were used to calibrate the models in a reasonable span of time. Results showed that even the adoption of a conceptual model for facies distribution clearly representative of the reservoir internal geometry might not guarantee reliable results in terms of production forecast. Furthermore, results also showed that realizations which seem fully acceptable after calibration were not representative of the true reservoir internal configuration and provided wrong production forecasts; conversely, realizations which did not show a good fit of the production data could reliably predict the reservoir

  14. Building energy modeling for green architecture and intelligent dashboard applications

    Science.gov (United States)

    DeBlois, Justin

    Buildings are responsible for 40% of the carbon emissions in the United States. Energy efficiency in this sector is key to reducing overall greenhouse gas emissions. This work studied the passive technique called the roof solar chimney for reducing the cooling load in homes architecturally. Three models of the chimney were created: a zonal building energy model, computational fluid dynamics model, and numerical analytic model. The study estimated the error introduced to the building energy model (BEM) through key assumptions, and then used a sensitivity analysis to examine the impact on the model outputs. The conclusion was that the error in the building energy model is small enough to use it for building simulation reliably. Further studies simulated the roof solar chimney in a whole building, integrated into one side of the roof. Comparisons were made between high and low efficiency constructions, and three ventilation strategies. The results showed that in four US climates, the roof solar chimney results in significant cooling load energy savings of up to 90%. After developing this new method for the small scale representation of a passive architecture technique in BEM, the study expanded the scope to address a fundamental issue in modeling - the implementation of the uncertainty from and improvement of occupant behavior. This is believed to be one of the weakest links in both accurate modeling and proper, energy efficient building operation. A calibrated model of the Mascaro Center for Sustainable Innovation's LEED Gold, 3,400 m2 building was created. Then algorithms were developed for integration to the building's dashboard application that show the occupant the energy savings for a variety of behaviors in real time. An approach using neural networks to act on real-time building automation system data was found to be the most accurate and efficient way to predict the current energy savings for each scenario. A stochastic study examined the impact of the

  15. General Meta-Models to Analysis of Software Architecture Definitions

    Directory of Open Access Journals (Sweden)

    GholamAli Nejad HajAli Irani

    2011-12-01

    Full Text Available An important step for understanding the architecture will be obtained by providing a clear definition from that. More than 150 valid definitions presented for identifying the software architecture. So an analogy among them is needed to give us a better understanding on the existing definitions. In this paper an analysis over different issues of current definitions is provided based on the incorporated elements. In conjunction with this objective first, the definitions are collected and, after conducting an analysis over them, are broken into different constituent elements which are shown in one table. Then some selected parameters in the table are classified into groups for comparison purposes. Then all parameters of each individual group are specified and compared with each other. This procedure is rendered for all groups respectively. Finally, a meta-model is developed for each group. The aim is not to accept or reject a specific definition, but rather is to contrast the definitions and their respective constituent elements in order to construct a background for gaining better perceptions on software architecture which in turn can benefit the introduction of an appropriate definition.

  16. Petroacoustic Modelling of Heterolithic Sandstone Reservoirs: A Novel Approach to Gassmann Modelling Incorporating Sedimentological Constraints and NMR Porosity data

    Science.gov (United States)

    Matthews, S.; Lovell, M.; Davies, S. J.; Pritchard, T.; Sirju, C.; Abdelkarim, A.

    2012-12-01

    Heterolithic or 'shaly' sandstone reservoirs constitute a significant proportion of hydrocarbon resources. Petroacoustic models (a combination of petrophysics and rock physics) enhance the ability to extract reservoir properties from seismic data, providing a connection between seismic and fine-scale rock properties. By incorporating sedimentological observations these models can be better constrained and improved. Petroacoustic modelling is complicated by the unpredictable effects of clay minerals and clay-sized particles on geophysical properties. Such effects are responsible for erroneous results when models developed for "clean" reservoirs - such as Gassmann's equation (Gassmann, 1951) - are applied to heterolithic sandstone reservoirs. Gassmann's equation is arguably the most popular petroacoustic modelling technique in the hydrocarbon industry and is used to model elastic effects of changing reservoir fluid saturations. Successful implementation of Gassmann's equation requires well-constrained drained rock frame properties, which in heterolithic sandstones are heavily influenced by reservoir sedimentology, particularly clay distribution. The prevalent approach to categorising clay distribution is based on the Thomas - Stieber model (Thomas & Stieber, 1975), this approach is inconsistent with current understanding of 'shaly sand' sedimentology and omits properties such as sorting and grain size. The novel approach presented here demonstrates that characterising reservoir sedimentology constitutes an important modelling phase. As well as incorporating sedimentological constraints, this novel approach also aims to improve drained frame moduli estimates through more careful consideration of Gassmann's model assumptions and limitations. A key assumption of Gassmann's equation is a pore space in total communication with movable fluids. This assumption is often violated by conventional applications in heterolithic sandstone reservoirs where effective porosity, which

  17. Tools for closed modelling of flow processes in geothermal reservoir engineering; Tools fuer die geschlossene Modellierung der Fliessprozesse im geothermischen Reservoir Engineering

    Energy Technology Data Exchange (ETDEWEB)

    Alkan, H.; Lorenz, S.; Mueller, W. [Inst. fuer Sicherheitstechnologie (ISTec) GmbH, Koeln (Germany)

    2002-07-01

    Three programs are presented for numeric modelling of a geothermal reservoir. An analytical lumped-parameter model TUI-GRS 1 based on the mass and energy balance in the presence of a supporting aquifer for the liquid systems H{sub 2}O-CO{sub 2} is recommended for a global and initial assessment of the future performance of a geothermal reservoir. For a more detailed performance study, an adapted 3D simulator for temperature-dependent multphase-multicomponent flow in porous media, TOUGH2, is available. Thirdly, a numeric borehole simulator TUI-GWS was developed for calculating pressure profiles and calcite precipitation during geothermal production. [German] Fuer die numerische Modellierung eines geothermischen Reservoirs werden drei Programme vorgestellt, mit denen die relevanten Prozesse im Bohrloch und im Reservoir modelliert werden koennen. Fuer eine globale und initiale Ausgangsschaetzung der zukuenftigen Leistung, eines geothermischen Reservoirs kann ein analytisches 'lumped-parameter-Modell' TUI-GRS 1, das auf Massen- und Energiebilanz in Anwesenheit eines unterstuetzenden Aquifers fuer fluessige Systeme H{sub 2}O-CO{sub 2} basiert, benutzt werden. Fuer eine ausfuehrliche Leistungsstudie des Reservoirs ist ein fuer geothermische Systeme angepasster 3-D-Simulator fuer temperaturabhaengige Mehrphasen-Mehrkomponenten-Stroemungen in poroesen Medien, TOUGH2, geeignet. Ein numerischer Bohrloch-Simulator TUI-GWS wurde entwickelt, um die Druckprofile sowie Kalzitausfaellung waehrend der geothermischen Produktion zu berechnen. (orig.)

  18. HIGH AND LOW RESOLUTION TEXTURED MODELS OF COMPLEX ARCHITECTURAL SURFACES

    Directory of Open Access Journals (Sweden)

    E. K. Stathopoulou

    2012-09-01

    Full Text Available During the recent years it has become obvious that 3D technology, applied mainly with the use of terrestrial laser scanners (TLS is the most suitable technique for the complete geometric documentation of complex objects, whether they are monuments or architectural constructions in general. However, it is rather a challenging task to convert an acquired point cloud into a realistic 3D polygonal model that can simultaneously satisfy high resolution modeling and visualization demands. The aim of the visualization of a simple or complex object is to create a 3D model that best describes the reality within the computer environment. This paper is dedicated especially in the visualization of a complex object's 3D model, through high, as well as low resolution textured models. The object of interest for this study was the Almoina (Romanesque Door of the Cathedral of Valencia in Spain.

  19. High and Low Resolution Textured Models of Complex Architectural Surfaces

    Science.gov (United States)

    Stathopoulou, E. K.; Valanis, A.; Lerma, J. L.; Georgopoulos, A.

    2011-09-01

    During the recent years it has become obvious that 3D technology, applied mainly with the use of terrestrial laser scanners (TLS) is the most suitable technique for the complete geometric documentation of complex objects, whether they are monuments or architectural constructions in general. However, it is rather a challenging task to convert an acquired point cloud into a realistic 3D polygonal model that can simultaneously satisfy high resolution modeling and visualization demands. The aim of the visualization of a simple or complex object is to create a 3D model that best describes the reality within the computer environment. This paper is dedicated especially in the visualization of a complex object's 3D model, through high, as well as low resolution textured models. The object of interest for this study was the Almoina (Romanesque) Door of the Cathedral of Valencia in Spain.

  20. Simulation Modeling of Space Missions Using the High Level Architecture

    Directory of Open Access Journals (Sweden)

    Luis Rabelo

    2013-01-01

    Full Text Available This paper discusses an environment being developed to model a mission of the Space Launch System (SLS and the Multipurpose Crew Vehicle (MPCV being launched from Kennedy Space Center (KSC to the International Space Station (ISS. Several models representing different phases of the mission such as the ground operations processes, engineered systems, and range components such as failure tree, blast, gas dispersion, and debris modeling are explained. These models are built using different simulation paradigms such as continuous, system dynamics, discrete-event, and agent-based simulation modeling. The High Level Architecture (HLA is the backbone of this distributed simulation. The different design decisions and the information fusion scheme of this unique environment are explained in detail for decision-making. This can also help in the development of exploration missions beyond the International Space Station.

  1. PEMODELAN DAERAH TANGKAPAN AIR WADUK KELILING DENGAN MODEL SWAT (Keliling Reservoir Catchment Area Modeling Using SWAT Model

    Directory of Open Access Journals (Sweden)

    Teuku Ferijal

    2015-05-01

    Full Text Available This study aimed to model watershed area of Keliling Reservoir using SWAT model. The reservoir is located in Aceh Besar District, Province of Aceh. The model was setup using 90m x 90m digital elevation model, land use data extracted from remote sensing data and soil characteristic obtained from laboratory analysis on soil samples. Model was calibrated using observed daily reservoir volume and the model performance was analyzed using RMSE-observations standard deviation ratio (RSR, Nash-Sutcliffe efficiency (NSE and percent bias (PBIAS. The model delineated the study area into 3,448 Ha having 13 subwatersheds and 76 land units (HRUs. The watershed is mostly covered by forest (53% and grassland (31%. The analysis revealed the 10 most sensitive parameters i.e. GW_DELAY, CN2, REVAPMN, ALPHA_BF, SOL_AWC, GW_REVAP, GWQMN, CH_K2 and ESCO. Model performances were categorized into very good for monthly reservoir volume with ENS 0.95, RSR 0.23, and PBIAS 2.97. The model performance decreased when it used to analyze daily reservoir inflow with ENS 0.55, RSR 0.67, and PBIAS 3.46. Keywords: Keliling Reservoir, SWAT, Watershed   ABSTRAK Penelitian ini bertujuan untuk untuk memodelkan daerah tangkapan air Waduk Keliling dengan menggunakan Model SWAT. Waduk Keliling terletak di Kabupaten Aceh Besar, Propinsi Aceh. Dalam penelitian ini Model SWAT dikembangkan berdasarkan data digital elevasi model resolusi 90 m x90 m, tata guna lahan yang diperoleh dari intepretasi citra satelit dan data soil dari hasil analisa sampel tanah yang diperoleh di daerah penelitian. Model dikalibrasi dengan data volume waduk dan kinerja model dianalisa menggunakan parameter rasio akar rata-rata kuadrat error dan standard deviasi observasi (RSR, efesiensi Nash-Sutcliffe (NSE dan persentase bias (PBIAS. Hasil deleniasi untuk daerah penelitian menghasilkan suatu DAS dengan luas 3,448 Ha dan memiliki 13 Sub DAS yang dikelompokkan menjadi 76 unit lahan. Sebagian besar wilayah study

  2. 3D Sedimentological and geophysical studies of clastic reservoir analogs: Facies architecture, reservoir properties, and flow behavior within delta front facies elements of the Cretaceous Wall Creek Member, Frontier Formation, Wyoming

    Energy Technology Data Exchange (ETDEWEB)

    Christopher D. White

    2009-12-21

    Significant volumes of oil and gas occur in reservoirs formed by ancient river deltas. This has implications for the spatial distribution of rock types and the variation of transport properties. A between mudstones and sandstones may form baffles that influence productivity and recovery efficiency. Diagenetic processes such as compaction, dissolution, and cementation can also alter flow properties. A better understanding of these properties and improved methods will allow improved reservoir development planning and increased recovery of oil and gas from deltaic reservoirs. Surface exposures of ancient deltaic rocks provide a high-resolution view of variability. Insights gleaned from these exposures can be used to model analogous reservoirs, for which data is sparser. The Frontier Formation in central Wyoming provides an opportunity for high-resolution models. The same rocks exposed in the Tisdale anticline are productive in nearby oil fields. Kilometers of exposure are accessible, and bedding-plane exposures allow use of high-resolution ground-penetrating radar. This study combined geologic interpretations, maps, vertical sections, core data, and ground-penetrating radar to construct geostatistical and flow models. Strata-conforming grids were use to reproduce the observed geometries. A new Bayesian method integrates outcrop, core, and radar amplitude and phase data. The proposed method propagates measurement uncertainty and yields an ensemble of plausible models for calcite concretions. These concretions affect flow significantly. Models which integrate more have different flow responses from simpler models, as demonstrated an exhaustive two-dimensional reference image and in three dimensions. This method is simple to implement within widely available geostatistics packages. Significant volumes of oil and gas occur in reservoirs that are inferred to have been formed by ancient river deltas. This geologic setting has implications for the spatial distribution of

  3. EOS simulation and GRNN modeling of the constant volume depletion behavior of gas condensate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Elsharkawy, A.M.; Foda, S.G. [Kuwait University, Safat (Kuwait). Petroleum Engineering Dept.

    1998-03-01

    Currently, two approaches are being used to predict the changes in retrograde gas condensate composition and estimate the pressure depletion behavior of gas condensate reservoirs. The first approach uses the equation of states whereas the second uses empirical correlations. Equations of states (EOS) are poor predictive tools for complex hydrocarbon systems. The EOS needs adjustment against phase behavior data of reservoir fluid of known composition. The empirical correlation does not involve numerous numerical computations but their accuracy is limited. This study presents two general regression neural network (GRNN) models. The first model, GRNNM1, is developed to predict dew point pressure and gas compressibility at dew point using initial composition of numerous samples while the second model, GRNNM2, is developed to predict the changes in well stream effluent composition at any stages of pressure depletion. GRNNM2 can also be used to determine the initial reservoir fluid composition using dew point pressure, gas compressibility at dew point, and reservoir temperature. These models are based on analysis of 142 sample of laboratory studies of constant volume depletion (CVD) for gas condensate systems forming a total of 1082 depletion stages. The database represents a wide range of gas condensate systems obtained worldwide. The performance of the GRNN models has been compared to simulation results of the equation of state. The study shows that the proposed general regression neural network models are accurate, valid, and reliable. These models can be used to forecast CVD data needed for many reservoir engineering calculations in case laboratory data is unavailable. The GRNN models save computer time involved in EOS calculations. The study also show that once these models are properly trained they can be used to cut expenses of frequent sampling and laborious experimental CVD tests required for gas condensate reservoirs. 55 refs., 13 figs., 6 tabs.

  4. Mathematical modeling of the thermal and hydrodynamic structure of the cooling reservoir

    Science.gov (United States)

    Saminskiy, G.; Debolskaya, E.

    2012-04-01

    Hydrothermal conditions of the cooling reservoir is determined by the heat and mass transfer from the water surface to the atmosphere and the processes of heat transfer directly in the water mass of the reservoir. As the capacity of power plants, the corresponding increase in the volume of heated water and the use of deep lakes and reservoirs as coolers there is a need to develop new, more accurate, and the application of existing methods for the numerical simulation. In calculating the hydrothermal regime it must take into account the effect of wind, density (buoyancy) forces, and other data of the cooling reservoir. In addition to solving practical problems it is important to know not only the magnitude of the average temperature, but also its area and depth distribution. A successful solution can be achieved through mathematical modeling of general systems of equations of transport processes and the correct formulation of the problem, based on appropriate initial data. The purpose of the work is application of software package GETM for simulating the hydrothermal regime of cooling reservoir with an estimate of three-dimensional structure of transfer processes, the effects of wind, the friction of the water surface. Three-dimensional models are rarely applied, especially for far-field problems. If such models are required, experts in the field must develop and apply them. Primary physical processes included are surface heat transfer, short-wave and long-wave radiation and penetration, convective mixing, wind and flow induced mixing, entrainment of ambient water by pumped-storage inflows, inflow density stratification as impacted by temperature and dissolved and suspended solids. The model forcing data consists of the system bathymetry developed into the model grid; the boundary condition flow and temperature; the tributary and flow and temperature; and the system meteorology. Ivankovskoe reservoir belongs to the reservoirs of valley type (Tver region, Russia). It

  5. Reservoir in Global Water Cycle: Macro Scale Hydrologic Modeling for Water Management

    Science.gov (United States)

    Zhou, T.; Nijssen, B.; Haddeland, I.; Gao, H.; Lettenmaier, D. P.

    2014-12-01

    Man-made reservoirs play a key role in the terrestrial water system. They support purposes, such as irrigation, hydropower generation, and flood control, which can substantially change water fluxes at the land surface and redistribute the storage of surface water in space and time. Although most developed countries have sophisticated observing systems for many variables in the natural surface water cycle, long-term and consistent records that focus on water management and human impacts on the global water cycle are much more limited, and most land surface models ignore water management activities. We describe a continental-scale model of reservoir storage, which is combined with a soil moisture deficit-based irrigation scheme within the Variable Infiltration Capacity (VIC) macro-scale hydrological model to simulate the effects of water management in the major river basins of the world. The model is forced with merged NCEP/NCAR and satellite meteorological data at a spatial resolution of 0.25 degrees latitude-longitude, for the period 1948 to 2010. A total of 167 of the largest reservoirs in the world with a total storage capacity around 3900 km3 (nearly 60% of the global total reservoir storage) are simulated. We successfully predict the monthly reservoir storage time series for most of a set of 23 global reservoirs for which observed storage is available either via in situ or satellite remote sensing measurements. We evaluate, on a continental and global basis, the magnitude of inter-seasonal and inter-annual reservoir storage variations in comparison with other terms in the land surface water cycle, including Snow Water Equivalent (SWE) and soil moisture.

  6. Architecture in motion: A model for music composition

    Science.gov (United States)

    Variego, Jorge Elias

    2011-12-01

    Speculations regarding the relationship between music and architecture go back to the very origins of these disciplines. Throughout history, these links have always reaffirmed that music and architecture are analogous art forms that only diverge in their object of study. In the 1 st c. BCE Vitruvius conceived Architecture as "one of the most inclusive and universal human activities" where the architect should be educated in all the arts, having a vast knowledge in history, music and philosophy. In the 18th c., the German thinker Johann Wolfgang von Goethe, described Architecture as "frozen music". More recently, in the 20th c., Iannis Xenakis studied the similar structuring principles between Music and Architecture creating his own "models" of musical composition based on mathematical principles and geometric constructions. The goal of this document is to propose a compositional method that will function as a translator between the acoustical properties of a room and music, to facilitate the creation of musical works that will not only happen within an enclosed space but will also intentionally interact with the space. Acoustical measurements of rooms such as reverberation time, frequency response and volume will be measured and systematically organized in correspondence with orchestrational parameters. The musical compositions created after the proposed model are evocative of the spaces on which they are based. They are meant to be performed in any space, not exclusively in the one where the acoustical measurements were obtained. The visual component of architectural design is disregarded; the room is considered a musical instrument, with its particular sound qualities and resonances. Compositions using the proposed model will not result as sonified shapes, they will be musical works literally "tuned" to a specific space. This Architecture in motion is an attempt to adopt scientific research to the service of a creative activity and to let the aural properties of

  7. Architecture for Integrated Medical Model Dynamic Probabilistic Risk Assessment

    Science.gov (United States)

    Jaworske, D. A.; Myers, J. G.; Goodenow, D.; Young, M.; Arellano, J. D.

    2016-01-01

    Probabilistic Risk Assessment (PRA) is a modeling tool used to predict potential outcomes of a complex system based on a statistical understanding of many initiating events. Utilizing a Monte Carlo method, thousands of instances of the model are considered and outcomes are collected. PRA is considered static, utilizing probabilities alone to calculate outcomes. Dynamic Probabilistic Risk Assessment (dPRA) is an advanced concept where modeling predicts the outcomes of a complex system based not only on the probabilities of many initiating events, but also on a progression of dependencies brought about by progressing down a time line. Events are placed in a single time line, adding each event to a queue, as managed by a planner. Progression down the time line is guided by rules, as managed by a scheduler. The recently developed Integrated Medical Model (IMM) summarizes astronaut health as governed by the probabilities of medical events and mitigation strategies. Managing the software architecture process provides a systematic means of creating, documenting, and communicating a software design early in the development process. The software architecture process begins with establishing requirements and the design is then derived from the requirements.

  8. Predicting chromatin architecture from models of polymer physics.

    Science.gov (United States)

    Bianco, Simona; Chiariello, Andrea M; Annunziatella, Carlo; Esposito, Andrea; Nicodemi, Mario

    2017-01-09

    We review the picture of chromatin large-scale 3D organization emerging from the analysis of Hi-C data and polymer modeling. In higher mammals, Hi-C contact maps reveal a complex higher-order organization, extending from the sub-Mb to chromosomal scales, hierarchically folded in a structure of domains-within-domains (metaTADs). The domain folding hierarchy is partially conserved throughout differentiation, and deeply correlated to epigenomic features. Rearrangements in the metaTAD topology relate to gene expression modifications: in particular, in neuronal differentiation models, topologically associated domains (TADs) tend to have coherent expression changes within architecturally conserved metaTAD niches. To identify the nature of architectural domains and their molecular determinants within a principled approach, we discuss models based on polymer physics. We show that basic concepts of interacting polymer physics explain chromatin spatial organization across chromosomal scales and cell types. The 3D structure of genomic loci can be derived with high accuracy and its molecular determinants identified by crossing information with epigenomic databases. In particular, we illustrate the case of the Sox9 locus, linked to human congenital disorders. The model in-silico predictions on the effects of genomic rearrangements are confirmed by available 5C data. That can help establishing new diagnostic tools for diseases linked to chromatin mis-folding, such as congenital disorders and cancer.

  9. Business Model Design and Architecture for the Internet of Everything

    Directory of Open Access Journals (Sweden)

    Dennis Pfisterer

    2016-04-01

    Full Text Available Smart devices and cyber-physical systems, which are interconnected to IT systems and services, form the basis for the arising Internet of Everything, opening up new economic opportunities for its participants and users beyond its technological aspects and challenges. While today’s e-business scenarios are mostly dominated by a few centralized online platforms, future business models, which will be feasible for the Internet of Everything, need to address special requirements. Such business models, e.g., leveraging the possibilities of smart cities, need to cope with arbitrary combinations of products and services orchestrated into complex products in a highly distributed and dynamic environment. Furthermore, these arbitrary combinations are influenced by real-time context information derived from sensor networks or IT systems, as well as the users’ requirements and preferences. The complexity of finding the optimal product/service combination overstrains users and leads to decisions according to the principle of adverse selection (i.e., choosing good enough instead of optimal. Such e-business models require an appropriate underlying value generation architecture that supports users in this process. In this paper, we develop a business model that addresses these problems. In addition, we present the Distributed Market Spaces (DMS software-system architecture as a possible implementation, which enables the aforementioned decentralized and context-centric e-business scenario and leverages the commercial possibilities of smart cities.

  10. A Functional Model of Sensemaking in a Neurocognitive Architecture

    Directory of Open Access Journals (Sweden)

    Christian Lebiere

    2013-01-01

    Full Text Available Sensemaking is the active process of constructing a meaningful representation (i.e., making sense of some complex aspect of the world. In relation to intelligence analysis, sensemaking is the act of finding and interpreting relevant facts amongst the sea of incoming reports, images, and intelligence. We present a cognitive model of core information-foraging and hypothesis-updating sensemaking processes applied to complex spatial probability estimation and decision-making tasks. While the model was developed in a hybrid symbolic-statistical cognitive architecture, its correspondence to neural frameworks in terms of both structure and mechanisms provided a direct bridge between rational and neural levels of description. Compared against data from two participant groups, the model correctly predicted both the presence and degree of four biases: confirmation, anchoring and adjustment, representativeness, and probability matching. It also favorably predicted human performance in generating probability distributions across categories, assigning resources based on these distributions, and selecting relevant features given a prior probability distribution. This model provides a constrained theoretical framework describing cognitive biases as arising from three interacting factors: the structure of the task environment, the mechanisms and limitations of the cognitive architecture, and the use of strategies to adapt to the dual constraints of cognition and the environment.

  11. A functional model of sensemaking in a neurocognitive architecture.

    Science.gov (United States)

    Lebiere, Christian; Pirolli, Peter; Thomson, Robert; Paik, Jaehyon; Rutledge-Taylor, Matthew; Staszewski, James; Anderson, John R

    2013-01-01

    Sensemaking is the active process of constructing a meaningful representation (i.e., making sense) of some complex aspect of the world. In relation to intelligence analysis, sensemaking is the act of finding and interpreting relevant facts amongst the sea of incoming reports, images, and intelligence. We present a cognitive model of core information-foraging and hypothesis-updating sensemaking processes applied to complex spatial probability estimation and decision-making tasks. While the model was developed in a hybrid symbolic-statistical cognitive architecture, its correspondence to neural frameworks in terms of both structure and mechanisms provided a direct bridge between rational and neural levels of description. Compared against data from two participant groups, the model correctly predicted both the presence and degree of four biases: confirmation, anchoring and adjustment, representativeness, and probability matching. It also favorably predicted human performance in generating probability distributions across categories, assigning resources based on these distributions, and selecting relevant features given a prior probability distribution. This model provides a constrained theoretical framework describing cognitive biases as arising from three interacting factors: the structure of the task environment, the mechanisms and limitations of the cognitive architecture, and the use of strategies to adapt to the dual constraints of cognition and the environment.

  12. A NUMERICAL PRESSURE TRANSIENT MODEL FOR MULTILAYERED GAS RESERVOIRS WITH PSEUDOSTEADY STATE FORMATION CROSSFLOW

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Reservoir deposition occurs over geologic periods of time. Although reservoirs are assumed to be homogenous for simplicity of analysis, most reservoirs are heterogeneous in nature. Some common forms of hetergeneity are the presence of layers and the presence of different zones of fluids and/or rock in the formation. A modified semi-permeable model for multi-layered gas reservoirs with pseudo-steady state interlayer crossflow was developed. The model accounted for the effect of skin and wellbore storage, considers all layers open to a single well, which flows at constant total rate. This new numerical solution was proved to be computationally very efficient, and it has been validated by comparing the results with those of some simple, well known models in the well testing literature. The effects of the reservoir parameters such as permeability, vertical permeability, skin, wellbore storage on the wellbore response, pressure and layer production rate were investigated. Numerical solutions of the problem for the modified semi-permeable model were used to find the structure of crossflow in typical cases.

  13. INTEGRATING PHYSIOLOGY AND ARCHITECTURE IN MODELS OF FRUIT EXPANSION

    Directory of Open Access Journals (Sweden)

    Mikolaj Cieslak

    2016-11-01

    Full Text Available Architectural properties of a fruit, such as its shape, vascular patterns, and skin morphology, play a significant role in determining the distributions of water, carbohydrates, and nutrients inside the fruit. Understanding the impact of these properties on fruit quality is difficult because they develop over time and are highly dependent on both genetic and environmental controls. We present a 3D functional-structural fruit model that can be used to investigate effects of the principle architectural properties on fruit quality. We use a three step modeling pipeline in the OpenAlea platform: (1 creating a 3D volumetric mesh representation of the internal and external fruit structure, (2 generating a complex network of vasculature that is embedded within this mesh, and (3 integrating aspects of the fruit’s function, such as water and dry matter transport, with the fruit’s structure. We restrict our approach to the phase where fruit growth is mostly due to cell expansion and the fruit has already differentiated into different tissue types. We show how fruit shape affects vascular patterns and, as a consequence, the distribution of sugar/water in tomato fruit. Furthermore, we show that strong interaction between tomato fruit shape and vessel density induces, independently of size, an important and contrasted gradient of water supply from the pedicel to the blossom end of the fruit. We also demonstrate how skin morphology related to microcracking distribution affects the distribution of water and sugars inside nectarine fruit. Our results show that such a generic model permits detailed studies of various, unexplored architectural features affecting fruit quality development.

  14. Building Structure Design as an Integral Part of Architecture: A Teaching Model for Students of Architecture

    Science.gov (United States)

    Unay, Ali Ihsan; Ozmen, Cengiz

    2006-01-01

    This paper explores the place of structural design within undergraduate architectural education. The role and format of lecture-based structure courses within an education system, organized around the architectural design studio is discussed with its most prominent problems and proposed solutions. The fundamental concept of the current teaching…

  15. Building Structure Design as an Integral Part of Architecture: A Teaching Model for Students of Architecture

    Science.gov (United States)

    Unay, Ali Ihsan; Ozmen, Cengiz

    2006-01-01

    This paper explores the place of structural design within undergraduate architectural education. The role and format of lecture-based structure courses within an education system, organized around the architectural design studio is discussed with its most prominent problems and proposed solutions. The fundamental concept of the current teaching…

  16. 3-D geomechanical modelling of a gas reservoir in the North German Basin: workflow for model building and calibration

    Directory of Open Access Journals (Sweden)

    K. Fischer

    2013-06-01

    Full Text Available The optimal use of conventional and unconventional hydrocarbon reservoirs depends, amongst others, on the local tectonic stress field. For example, wellbore stability, orientation of hydraulically induced fractures and – especially in fractured reservoirs – permeability anisotropies are controlled by the recent in situ stresses. Faults and lithological changes can lead to stress perturbations and produce local stresses that can significantly deviate from the regional stress field. Geomechanical reservoir models aim for a robust, ideally "pre-drilling" prediction of the local variations in stress magnitude and orientation. This requires a~numerical modelling approach that is capable to incorporate the specific geometry and mechanical properties of the subsurface reservoir. The workflow presented in this paper can be used to build 3-D geomechanical models based on the Finite Element Method (FEM and ranging from field-scale models to smaller, detailed submodels of individual fault blocks. The approach is successfully applied to an intensively faulted gas reservoir in the North German Basin. The in situ stresses predicted by the geomechanical FE model were calibrated against stress data actually observed, e.g. borehole breakouts and extended leak-off tests. Such a validated model can provide insights into the stress perturbations in the inter-well space and undrilled parts of the reservoir. In addition, the tendency of the existing fault network to slip or dilate in the present-day stress regime can be addressed.

  17. Simple multistage closed-(box+reservoir) models of chemical evolution: an application to the inner Galactic halo

    CERN Document Server

    Caimmi, R

    2010-01-01

    Simple closed-box (CB) models of chemical evolution are extended on two respects: (i) simple closed-(box+reservoir) (CBR) models allowing gas outflow from the box into the reservoir or gas inflow into the box from the reservoir with same composition as the preexisting gas and rate proportional to the star formation rate, and (ii) simple multistage closed-(box+reservoir) (MCBR) models allowing different stages of evolution characterized by different inflow or outflow rates. The stellar initial mass function is assumed to be universal, and mass conservation holds for the whole system (box+reservoir) while it is violated for each subsystem (box and reservoir). The theoretical differential oxygen abundance distribution (TDOD) predicted by the model, under the assumption of instantaneous recycling, is a continuous broken line, where different slopes are related to different inflow rates. For an application of the model (a) a fictitious sample is built up from two distinct samples and taken as representative of the...

  18. Trade-off Assessment of Simplified Routing Models for Short-Term Hydropower Reservoir Optimization

    Science.gov (United States)

    Issao Kuwajima, Julio; Schwanenberg, Dirk; Alvardo Montero, Rodolfo; Mainardi Fan, Fernando; Assis dos Reis, Alberto

    2014-05-01

    Short-term reservoir optimization, also referred to as model predictive control, integrates model-based forecasts and optimization algorithms to meet multiple management objectives such as water supply, navigation, hydroelectricity generation, environmental obligations and flood protection. It is a valuable decision support tool to handle water-stress conditions or flooding events, and supports decision makers to minimize their impact. If the reservoir management includes downstream control, for example for mitigation flood damages in inundation areas downstream of the operated dam, the flow routing between the dam and the downstream inundation area is of major importance. The unsteady open channel flow in river reaches can be described by the one-dimensional Saint-Venant equations. However, owing to the mathematical complexity of those equations, some simplifications may be required to speed up the computation within the optimization procedure. Another strategy to limit the model runtime is a schematization on a course computational grid. In particular the last measure can introduce significant numerical diffusion into the solution. This is a major drawback, in particular if the reservoir release has steep gradients which we often find in hydropower reservoirs. In this work, four different routing models are assessed concerning their implementation in the predictive control of the Três Marias Reservoir located at the Upper River São Francisco in Brazil: i) a fully dynamic model using the software package SOBEK; ii) a semi-distributed rainfall-runoff model with Muskingum-Cunge routing for the flow reaches of interest, the MGB-IPH (Modelo Hidrológico de Grandes Bacias - Instituto de Pesquisas Hidráulicas); iii) a reservoir routing approach; and iv) a diffusive wave model. The last two models are implemented in the RTC-Tool toolbox. The overall model accuracy between the simplified models in RTC-Tools (iii, iv) and the more sophisticated SOBEK model (i) are

  19. Numerical modeling of temperature and species distributions in hydrocarbon reservoirs

    Science.gov (United States)

    Bolton, Edward W.; Firoozabadi, Abbas

    2014-01-01

    We examine bulk fluid motion and diffusion of multicomponent hydrocarbon species in porous media in the context of nonequilibrium thermodynamics, with particular focus on the phenomenology induced by horizontal thermal gradients at the upper and lower horizontal boundaries. The problem is formulated with respect to the barycentric (mass-averaged) frame of reference. Thermally induced convection, with fully time-dependent temperature distributions, can lead to nearly constant hydrocarbon composition, with minor unmixing due to thermal gradients near the horizontal boundaries. Alternately, the composition can be vertically segregated due to gravitational effects. Independent and essentially steady solutions have been found to depend on how the compositions are initialized in space and may have implications for reservoir history. We also examine injection (to represent filling) and extraction (to represent leakage) of hydrocarbons at independent points and find a large distortion of the gas-oil contact for low permeability.

  20. Comparison of risk-based optimization models for reservoir management

    Energy Technology Data Exchange (ETDEWEB)

    Mahootchi, M. [Amirkabir Univ. of Technology, Tehran (Iran, Islamic Republic of). Dept. of Industrial Engineering; Ponnambalam, K.; Tizhoosh, H.R. [Waterloo Univ., ON (Canada). Dept. of Systems Design Engineering

    2010-01-15

    The stochastic nature of input variables in water resource management problems must be carefully considered during decision-making processes. This paper used a single reservoir optimization problem in which 2-stage stochastic programming (TSP) and Fletcher-Ponnambalam (FP) were used to generate open-loop policies where inflows and water prices were uncertain. A simulation was performed to measure the performance of FP and TSP techniques in embedding risk and producing comparable policies. A simulation-based Q-learning algorithm based on reinforcement learning (RL) was used to determine the squared action-value function or each action-state pair produced by the algorithm. The methods were used to produce the trade-off curve between expected benefits and standard deviations of benefits. The study showed that the FP method does not require simulation, while the TSP and Q-learning methods both required simulations. 39 refs., 9 tabs., 4 figs.

  1. Calculation of shocks in oil reservoir modeling and porous flow

    Energy Technology Data Exchange (ETDEWEB)

    Concus, P.

    1982-03-01

    For many enhanced recovery methods propagating fronts arise that may be steep or discontinuous. One example is the waterflooding of a petroleum reservoir, in which there is forced out residual oil that remains after outflow by decompression has declined. In this paper high-resolution numerical methods to solve porous flow problems having propagating discontinuities are discussed. The random choice method can track solution discontinuities sharply and accurately for one space dimension. The first phase of this study adapted this method for solving the Buckley-Leverett equation for immiscible displacement in one space dimension. Extensions to more than one space dimension for the random choice method were carried out subsequently by means of fractional splitting. Because inaccuracies could be introduced for some problems at dicontinuity fronts propagating obliquely to the splitting directions, efforts are currently being directed at investigating alternatives for multidimensional cases.

  2. Spectrum emission considerations for baseband-modeled CALLUM architectures

    DEFF Research Database (Denmark)

    Strandberg, Roland; Andreani, Pietro; Sundström, Lars

    2005-01-01

    . Simulation examples are presented on how three different CALLUM architectures behave for enhanced data rates for global system for mobile communications evolution and wide-band code-division multiple-access signals. In addition, we have considered the effects of loop time delay, which is the ultimate...... of the control equations governing it. The main purpose of this paper has been the derivation of a linearized model for the control equations, which enables the use of linear network theory in the study of CALLUM. In particular, it can be used to analyze the stability and maximize the bandwidth of the system...

  3. Analysis of Seismicity Risk Increase Triggered by Longtan Reservoir, China, Using a Fully Coupled Poroelastic Model

    Science.gov (United States)

    Deng, K.; Zhang, S.; Guo, Y.; Zhou, S.; Liu, Y.

    2015-12-01

    Impoundment of reservoirs can lead to increase in crustal pore pressure and Coulomb stress, and promotes nearby faults to fail. Abnormal seismicity increase around reservoir is often thought to be triggered by the water impounded behind the dam. In this study, we analyze the impact of Longtan reservoir in Guangxi province, southwest China, on local seismicity, which has increased significantly since the initial impoundment in October, 2006. Most of the earthquakes cluster around the reservoir according to local seismic network and CEA reports, and the greatest earthquake is of magnitude 4.2. We introduce an improved Bayesian method to show that the temporal variation of b-value is inversely correlated with the seasonal fluctuation of reservoir water level. Upon extracting background seismicity using the Epidemic Type Aftershock Sequence (ETAS) model, we show that background seismicity variation is highly related to the filling rate and volume We further investigate the mechanism of seismicity increase and reservoir impoundment by performing a fully coupled 3-D poroelastic model with the reservoir loading history as a dynamic boundary condition. An optimally oriented fault plane is chosen according to the regional stress field and GPS deformation data when calculating the induced Coulomb stress. Our results demonstrate that most earthquakes occurred within positive Coulomb stress regime, and the seismicity rate is highly related to the rate of pore pressure increase. In the next step we plan to apply the coupled poroelastic model to understand hydraulic fracturing induced earthquakes in shale gas exploration, such as the recent Fox Creek event cluster, in the western Canada sedimentary basin.

  4. A Combined Thermodynamic and Kinetic Model for Barite Prediction at Oil Reservoir Conditions

    DEFF Research Database (Denmark)

    Zhen Wu, Bi Yun

    of this research was to develop a model, based on thermodynamics and kinetics, for predicting barite precipitation rates in saline waters at the pressures and temperatures of oil bearing reservoirs, using the geochemical modelling code PHREEQC. This task is complicated by the conditions where traditional methods....... Calculations for a well with seawater breakthrough results in an overestimation compared to scale samples, suggesting that significant amounts of barite precipitate in the reservoirs prior to entering to the wells. The combined model allows estimates of barite scaling rates that can be compared with field......In marine environments, barite (BaSO4) is a key proxy that has been used for understanding the biological and chemical evolution of oceans and for tracking the origin of fluids. In the oil industry, barite scale can clog pipelines and pores in the reservoirs, reducing oil yield. The goal...

  5. An architecture model for multiple disease management information systems.

    Science.gov (United States)

    Chen, Lichin; Yu, Hui-Chu; Li, Hao-Chun; Wang, Yi-Van; Chen, Huang-Jen; Wang, I-Ching; Wang, Chiou-Shiang; Peng, Hui-Yu; Hsu, Yu-Ling; Chen, Chi-Huang; Chuang, Lee-Ming; Lee, Hung-Chang; Chung, Yufang; Lai, Feipei

    2013-04-01

    Disease management is a program which attempts to overcome the fragmentation of healthcare system and improve the quality of care. Many studies have proven the effectiveness of disease management. However, the case managers were spending the majority of time in documentation, coordinating the members of the care team. They need a tool to support them with daily practice and optimizing the inefficient workflow. Several discussions have indicated that information technology plays an important role in the era of disease management. Whereas applications have been developed, it is inefficient to develop information system for each disease management program individually. The aim of this research is to support the work of disease management, reform the inefficient workflow, and propose an architecture model that enhance on the reusability and time saving of information system development. The proposed architecture model had been successfully implemented into two disease management information system, and the result was evaluated through reusability analysis, time consumed analysis, pre- and post-implement workflow analysis, and user questionnaire survey. The reusability of the proposed model was high, less than half of the time was consumed, and the workflow had been improved. The overall user aspect is positive. The supportiveness during daily workflow is high. The system empowers the case managers with better information and leads to better decision making.

  6. A mathematical model for preflush treatment in an oil reservoir using a fully miscible fluid

    NARCIS (Netherlands)

    F.J. Vermolen; G.-J. Pieters; P.L.J. Zitha; J. Bruining

    1999-01-01

    textabstractIn this paper we propose and analyse a mathematical model for preflush treatment in an oil reservoir. The model is based on two phase flow in which both phases are fully miscible. For the case of constant injection rate condition, fully implicit solutions can be constructed. Saturation p

  7. An Integrated Modeling Approach for Describing Fate and Transport of Perfluorinated Compounds (PFCs) in Estuarine Reservoir

    Science.gov (United States)

    Zhang, J.; Nguyen Viet, T.; Wang, X.; Chen, H.; Gin, K. Y. H.

    2014-12-01

    The fate and transport processes of emerging contaminants in aquatic ecosystems are complex, which are not only determined by their own properties but also influenced by the environmental setting, physical, chemical and biological processes. A 3D-emerging contaminant model has been developed based on Delft3D water quality model and coupled with a hydrodynamic model and a catchment-scale 1D- hydrological and hydraulic model to study the possible fate and transport mechanisms of perfluorinated compounds (PFCs) in Marina Reservoir in Singapore. The main processes in the contaminant model include partitioning (among detritus, dissolved organic matter and phytoplankton), settling, resuspension and degradation. We used the integrated model to quantify the distribution of the total PFCs and two major components, namely perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) in the water, sediments and organisms in the reservoir. The model yielded good agreement with the field measurements when evaluated based on the datasets in 2009 and 2010 as well as recent observations in 2013 and 2014. Our results elucidate that the model can be a useful tool to characterize the occurrence, sources, sinks and trends of PFCs both in the water column and in the sediments in the reservoir. Thisapproach provides a better understanding of mechanisms that influence the fate and transport of emerging contaminants and lays down a framework for future experiments to further explore how the dominant environmental factors change towards mitigation of emerging contaminants in the reservoirs.

  8. Advanced Techniques for Reservoir Simulation and Modeling of Non-Conventional Wells

    Energy Technology Data Exchange (ETDEWEB)

    Durlofsky, Louis J.; Aziz, Khalid

    2001-08-23

    Research results for the second year of this project on the development of improved modeling techniques for non-conventional (e.g., horizontal, deviated or multilateral) wells were presented. The overall program entails the development of enhanced well modeling and general simulation capabilities. A general formulation for black-oil and compositional reservoir simulation was presented.

  9. A model based safety architecture framework for Dutch high speed train lines

    NARCIS (Netherlands)

    Schuitemaker, K.; Braakhuis, J.G.; Rajabalinejad, M.

    2015-01-01

    This paper presents a model-based safety architecture framework (MBSAF) for capturing and sharing architectural knowledge of safety cases of safetycritical systems of systems (SoS). Whilst architecture frameworks in the systems engineering domain consider safety often as dependent attribute, this st

  10. Lithofacies Architecturing and Hydrocarbon Reservoir Potential of Lumshiwal Formation: Surghar Range, Trans-Indus Ranges, North Pakistan

    Directory of Open Access Journals (Sweden)

    Iftikhar Alam

    2015-12-01

    directed Paleo-current system prevailed during deposition of Lumshiwal Formation. Diagenetic and tectonically induced fractures make the formation exceedingly porous and permeable as suitable reservoir horizon for the accumulation of hydrocarbon in the Trans-Indus ranges. The same formation has already been proven as potential reservoir horizon for hydrocarbon in the Kohat Plateau of northwest Pakistan. Secondly, the formation is dominantly comprised of silica/quartz sandstone (quartzarenite which can be used as silica sand, one of the essential raw materials for glass industries. The formation is also comprised of local coal seams which can be mined for production of coal in the region.

  11. Requirements on catchment modelling for an optimized reservoir operation in water deficient regions

    Science.gov (United States)

    Froebrich, J.; Kirkby, M. J.; Reder, C.

    2002-12-01

    To provide long term water security in water deficient regions, the interaction of erosion, pollutant emission, the impact of irrigation areas, the characteristics of ephemeral streams and resulting water quality in reservoirs must be considered in water management plans. In many semiarid regions, reservoirs are the only source of water, the indispensable element required for human existence. By the year 2000 the world had built many small and > 45,000 large dams. In these reservoirs, water quality and quantity are affected both by climate change and catchment land use. Results of past projects indicate that the specific control of reservoirs can lead to a significant improvement of water quality, but reservoirs have already transformed the quantity and quality of surface waters in a remarkable manner. Reservoirs with their distinct behaviour as reactors could therefore be considered as key elements in semiarid and arid catchments, linking and transforming rivers and channels. Effective practical operation schemes require a thorough knowledge of spatial and temporal variation in water quality and quantity, and simulation models can be used to support the identification of most effective management potentials at catchment scale. We discuss here the particular requirements for water quality modelling at catchment scale in semiarid and arid regions. Results of reservoir water quality modelling are presented. The potential of catchment models like the PESERA model is demonstrated. Knowledge gaps, such as the consideration of ephemeral streams in catchment models, are addressed and fresh problem solving strategies are introduced. Erosion models like PESERA can provide important information on sediment transport and hence describing the carrier potentials for organic matter, heavy metals and pesticides from terrestrial areas into the water courses. The new EU-research project tempQsim will improve understanding of how the organic matter is transformed in river beds

  12. Large scale 2D numerical modelling of reservoirs sedimentation and flushing operations

    OpenAIRE

    Dewals, Benjamin; Erpicum, Sébastien; Archambeau, Pierre; Detrembleur, Sylvain; Fraikin, Catherine; Pirotton, Michel

    2004-01-01

    The quasi-3D flow solver WOLF has been developed at the University of Liege for almost a decade. It has been used to carry out the simulation of silting processes in large reservoirs and to predict the efficiency of flushing operations. Besides briefly depicting the mathematical and numerical model, the present paper demonstrates its applicability on the case of a large hydropower project in India. The silting process of the reservoir has been simulated by means of the quasi-3D flow model wit...

  13. Depositional sequence analysis and sedimentologic modeling for improved prediction of Pennsylvanian reservoirs (annex I). Eleventh quarterly technical progress report, July 1, 1992--September 30, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Watney, W.L.

    1994-09-01

    The objectives of this research are to: (1) assist producers in locating and producing petroleum not currently being produced because of technological problems or the inability to identify details of reservoir compartmentalization, (2) to decrease risk in field development, and (3) accelerate the retrieval and analysis of baseline geoscience information for initial reservoir description. The interdisciplinary data sought in this research will be used to resolve specific problems in correlation of strata and to establish the mechanisms responsible for the Upper Pennsylvanian stratigraphic architecture in the Midcontinent. The data will better constrain ancillary problems related to the validation of depositional sequence and subsequence correlation, subsidence patterns, sedimentation rates, sea-level changes, and the relationship of sedimentary sequences to basement terrains. The geoscientific information, including data from field studies, surface and near-surface reservoir analogues, and regional data base development, will also be used for development of geologic computer process-based simulation models tailored to specific depositional sequences for use in improving prediction of reservoir characteristics.

  14. Modelling architectures in multi-product oriented technology development

    DEFF Research Database (Denmark)

    Guðlaugsson, Tómas Vignir

    This thesis investigates the use of architecture modelling in a technology development context.This context presents greater uncertainties than more mature new product development. Applications—the use of products based on the technology being developed—are not fully identified and the requiremen...... frameworks in a technology development projectare presented, along with descriptive results on the context of technology development gained through active participation in the case project.......This thesis investigates the use of architecture modelling in a technology development context.This context presents greater uncertainties than more mature new product development. Applications—the use of products based on the technology being developed—are not fully identified and the requirements...... to be fulfilled are not completely defined.The products to be based on the technology are yet to be developed as the foundation for their development will be developed during the technology development. Furthermore, the production of a new technology is not defined as both the technology and derivative products...

  15. Constructing reservoir-scale 3D geomechanical FE-models. A refined workflow for model generation and calculation

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, K.; Henk, A. [Technische Univ. Darmstadt (Germany). Inst. fuer Angewandte Geowissenschaften

    2013-08-01

    The tectonic stress field strongly affects the optimal exploitation of conventional and unconventional hydrocarbon reservoirs. Amongst others, wellbore stability, orientation of hydraulically induced fractures and - particularly in fractured reservoirs - permeability anisotropies depend on the magnitudes and orientations of the recent stresses. Geomechanical reservoir models can provide unique insights into the tectonic stress field revealing the local perturbations resulting from faults and lithological changes. In order to provide robust predictions, such numerical models are based on the finite element (FE) method and account for the complexities of real reservoirs with respect to subsurface geometry, inhomogeneous material distribution and nonlinear rock mechanical behavior. We present a refined workflow for geomechanical reservoir modeling which allows for an easier set-up of the model geometry, high resolution submodels and faster calculation times due to element savings in the load frame. Transferring the reservoir geometry from the geological subsurface model, e.g., a Petrel {sup registered} project, to the FE model represents a special challenge as the faults are discontinuities in the numerical model and no direct interface exists between the two software packages used. Point clouds displaying faults and lithostratigraphic horizons can be used for geometry transfer but this labor-intensive approach is not feasible for complex field-scale models with numerous faults. Instead, so-called Coon's patches based on horizon lines, i.e. the intersection lines between horizons and faults, are well suited to re-generate the various surfaces in the FE software while maintaining their topology. High-resolution submodels of individual fault blocks can be incorporated into the field-scale model. This allows to consider both a locally refined mechanical stratigraphy and the impact of the large-scale fault pattern. A pressure load on top of the model represents the

  16. High-Speed Photonic Reservoir Computing Using a Time-Delay-Based Architecture: Million Words per Second Classification

    Directory of Open Access Journals (Sweden)

    Laurent Larger

    2017-02-01

    Full Text Available Reservoir computing, originally referred to as an echo state network or a liquid state machine, is a brain-inspired paradigm for processing temporal information. It involves learning a “read-out” interpretation for nonlinear transients developed by high-dimensional dynamics when the latter is excited by the information signal to be processed. This novel computational paradigm is derived from recurrent neural network and machine learning techniques. It has recently been implemented in photonic hardware for a dynamical system, which opens the path to ultrafast brain-inspired computing. We report on a novel implementation involving an electro-optic phase-delay dynamics designed with off-the-shelf optoelectronic telecom devices, thus providing the targeted wide bandwidth. Computational efficiency is demonstrated experimentally with speech-recognition tasks. State-of-the-art speed performances reach one million words per second, with very low word error rate. Additionally, to record speed processing, our investigations have revealed computing-efficiency improvements through yet-unexplored temporal-information-processing techniques, such as simultaneous multisample injection and pitched sampling at the read-out compared to information “write-in”.

  17. High-Speed Photonic Reservoir Computing Using a Time-Delay-Based Architecture: Million Words per Second Classification

    Science.gov (United States)

    Larger, Laurent; Baylón-Fuentes, Antonio; Martinenghi, Romain; Udaltsov, Vladimir S.; Chembo, Yanne K.; Jacquot, Maxime

    2017-01-01

    Reservoir computing, originally referred to as an echo state network or a liquid state machine, is a brain-inspired paradigm for processing temporal information. It involves learning a "read-out" interpretation for nonlinear transients developed by high-dimensional dynamics when the latter is excited by the information signal to be processed. This novel computational paradigm is derived from recurrent neural network and machine learning techniques. It has recently been implemented in photonic hardware for a dynamical system, which opens the path to ultrafast brain-inspired computing. We report on a novel implementation involving an electro-optic phase-delay dynamics designed with off-the-shelf optoelectronic telecom devices, thus providing the targeted wide bandwidth. Computational efficiency is demonstrated experimentally with speech-recognition tasks. State-of-the-art speed performances reach one million words per second, with very low word error rate. Additionally, to record speed processing, our investigations have revealed computing-efficiency improvements through yet-unexplored temporal-information-processing techniques, such as simultaneous multisample injection and pitched sampling at the read-out compared to information "write-in".

  18. Model-to-model transformations of architecture descriptions of an integration platform

    Directory of Open Access Journals (Sweden)

    Tomasz Górski

    2014-04-01

    Full Text Available Model transformations play a key role in any software development project based on Mod-el-Driven Engineering (MDE principles. However, little attention has been paid to the ap-plication of MDE principles to automate the design of integration solutions. The aim of the paper is to present transformations of a model-to-model type, used to automate the process of integration platform's architecture description. The transformations have been designed to enable the generation of model elements, according to the '1+5' architectural views model adjusted to the integration solutions description. Design and implementation of transformations were performed in the IBM Rational Software Architect (RSA environ-ment. Authorial UML profiles: UML Profile for Integration Platform and UML Profile for Integration Flows have been used. The paper covers transformations between models in the following architectural views: Integrated Processes; Use Cases; Logical and Integrated Services. The transformations occur at the levels of business processes, requirements speci-fication and system design. Using the transformations, it is possible to generate models, diagrams, model elements and relationships between them. The complete environment has been obtained to automate architectural description of an integration solution. Transfor-mations ensure completeness of the architectural description and consistency of elements between models.

  19. Heuristic Algorithm with Simulation Model for Searching Optimal Reservoir Rule Curves

    Directory of Open Access Journals (Sweden)

    Anongrit Kangrang

    2009-01-01

    Full Text Available This study proposes a heuristic algorithm to connect with simulation model for searching the optimal reservoir rule curves. The proposed model was applied to determine the optimal rule curves of the Ubolratana reservoir (the Chi River Basin, Thailand. The results showed that the pattern of the obtained rule curves similar to the existing rule curve. Then the obtained rule curves were used to simulate the Ubolratana reservoir system with the synthetic inflows. The results indicated that the frequency of water shortage and the average water shortage are reduced to 44.31 and 43.75% respectively, the frequency of excess release and the average excess release are reduced to 24.08% and 22.81%.

  20. Forecasting monthly inflow discharge of the Iffezheim reservoir using data-driven models

    Science.gov (United States)

    Zhang, Qing; Aljoumani, Basem; Hillebrand, Gudrun; Hoffmann, Thomas; Hinkelmann, Reinhard

    2017-04-01

    River stream flow is an essential element in hydrology study fields, especially for reservoir management, since it defines input into reservoirs. Forecasting this stream flow plays an important role in short or long-term planning and management in the reservoir, e.g. optimized reservoir and hydroelectric operation or agricultural irrigation. Highly accurate flow forecasting can significantly reduce economic losses and is always pursued by reservoir operators. Therefore, hydrologic time series forecasting has received tremendous attention of researchers. Many models have been proposed to improve the hydrological forecasting. Due to the fact that most natural phenomena occurring in environmental systems appear to behave in random or probabilistic ways, different cases may need a different methods to forecast the inflow and even a unique treatment to improve the forecast accuracy. The purpose of this study is to determine an appropriate model for forecasting monthly inflow to the Iffezheim reservoir in Germany, which is the last of the barrages in the Upper Rhine. Monthly time series of discharges, measured from 1946 to 2001 at the Plittersdorf station, which is located 6 km downstream of the Iffezheim reservoir, were applied. The accuracies of the used stochastic models - Fiering model and Auto-Regressive Integrated Moving Average models (ARIMA) are compared with Artificial Intelligence (AI) models - single Artificial Neural Network (ANN) and Wavelet ANN models (WANN). The Fiering model is a linear stochastic model and used for generating synthetic monthly data. The basic idea in modeling time series using ARIMA is to identify a simple model with as few model parameters as possible in order to provide a good statistical fit to the data. To identify and fit the ARIMA models, four phase approaches were used: identification, parameter estimation, diagnostic checking, and forecasting. An automatic selection criterion, such as the Akaike information criterion, is utilized

  1. Hydro-mechanically coupled modelling of deep-seated rock slides in the surroundings of reservoirs

    Science.gov (United States)

    Lechner, Heidrun; Preh, Alexander; Zangerl, Christian

    2016-04-01

    In order to enhance the understanding of the behaviour of deep-seated rock slides in the surroundings of large dam reservoirs, this study concentrates on failure mechanisms, deformation processes and the ability of self-stabilisation of rock slides influenced by reservoirs. Particular focus is put on internal rock mass deformations, progressive topographical slope changes due to reservoir impoundment and shear displacements along the basal shear zone in relation to its shear strength properties. In this study, a two-dimensional numerical rock slide model is designed by means of the Universal Distinct Element Code UDEC and investigated concerning different groundwater flow scenarios. These include: (i) a completely drained rock slide model, (ii) a model with fully saturated rock mass below an inclined groundwater table and (iii) a saturated groundwater model with a reservoir at the slope toe. Slope displacements initiate when the shear strength properties of the basal shear zone are at or below the critical parameters for the limit-equilibrium state and continue until a numerical equilibrium is reached due to deformation- and displacement-based geometrical changes. The study focuses on the influence of a reservoir at the toe of a rock slide and tries to evaluate the degree of displacement which is needed for a re-stabilisation in relation to the geometrical characteristics of the rock slide. Besides, challenges and limitations of applied distinct element methods to simulate large strain and displacements of deep-seated rock slides are discussed. The ongoing study will help to understand the deformation behaviour of deep-seated pre-existing rock slides in fractured rock mass during initial impounding and will be part of a hazard assessment for large reservoirs.

  2. Geomechanical modeling of reservoir compaction, surface subsidence, and casing damage at the Belridge diatomite field

    Energy Technology Data Exchange (ETDEWEB)

    FREDRICH,JOANNE T.; DEITRICK,G.L.; ARGUELLO JR.,JOSE G.; DEROUFFIGNAC,E.P.

    2000-05-01

    Geologic, and historical well failure, production, and injection data were analyzed to guide development of three-dimensional geomechanical models of the Belridge diatomite field, California. The central premise of the numerical simulations is that spatial gradients in pore pressure induced by production and injection in a low permeability reservoir may perturb the local stresses and cause subsurface deformation sufficient to result in well failure. Time-dependent reservoir pressure fields that were calculated from three-dimensional black oil reservoir simulations were coupled uni-directionally to three-dimensional non-linear finite element geomechanical simulations. The reservoir models included nearly 100,000 gridblocks (100--200 wells), and covered nearly 20 years of production and injection. The geomechanical models were meshed from structure maps and contained more than 300,000 nodal points. Shear strain localization along weak bedding planes that causes casing dog-legs in the field was accommodated in the model by contact surfaces located immediately above the reservoir and at two locations in the overburden. The geomechanical simulations are validated by comparison of the predicted surface subsidence with field measurements, and by comparison of predicted deformation with observed casing damage. Additionally, simulations performed for two independently developed areas at South Belridge, Sections 33 and 29, corroborate their different well failure histories. The simulations suggest the three types of casing damage observed, and show that although water injection has mitigated surface subsidence, it can, under some circumstances, increase the lateral gradients in effective stress, that in turn can accelerate subsurface horizontal motions. Geomechanical simulation is an important reservoir management tool that can be used to identify optimal operating policies to mitigate casing damage for existing field developments, and applied to incorporate the effect of

  3. High level architecture evolved modular federation object model

    Institute of Scientific and Technical Information of China (English)

    Wang Wenguang; Xu Yongping; Chen Xin; Li Qun; Wang Weiping

    2009-01-01

    To improve the agility, dynamics, composability, reusability, and development efficiency restricted by monolithic federation object model (FOM), a modular FOM is proposed by high level architecture (HLA) evolved product development group. This paper reviews the state-of-the-art of HLA evolved modular FOM. In particular, related concepts, the overall impact on HLA standards, extension principles, and merging processes are discussed. Also permitted and restricted combinations, and merging rules are provided, and the influence on HLA interface specification is given. The comparison between modular FOM and base object model (BOM) is performed to illustrate the importance of their combination. The applications of modular FOM are summarized. Finally, the significance to facilitate compoable simulation both in academia and practice is presented and future directions are pointed out.

  4. High level architecture evolved modular federation object model

    CERN Document Server

    Wang, Wenguang; Chen, Xin; Li, Qun; Wang, Weiping

    2009-01-01

    To improve the agility, dynamics, composability, reusability, and development efficiency restricted by monolithic Federation Object Model (FOM), a modular FOM was proposed by High Level Architecture (HLA) Evolved product development group. This paper reviews the state-of-the-art of HLA Evolved modular FOM. In particular, related concepts, the overall impact on HLA standards, extension principles, and merging processes are discussed. Also permitted and restricted combinations, and merging rules are provided, and the influence on HLA interface specification is given. The comparison between modular FOM and Base Object Model (BOM) is performed to illustrate the importance of their combination. The applications of modular FOM are summarized. Finally, the significance to facilitate composable simulation both in academia and practice is presented and future directions are pointed out.

  5. Geomechanical reservoir models. A case study from the Sirte Basin / Libya

    Energy Technology Data Exchange (ETDEWEB)

    Henk, Andreas [Freiburg Univ. (Germany). Inst. fuer Geowissenschaften; Frischbutter, Andreas [Wintershall Holding AG, Kassel (Germany); Tawengi, Khaeri Segayer [National Oil Company, Tripoli (Libya)

    2010-03-15

    Geomechanical reservoir models on the basis of numerical simulation techniques provide a tool for the prediction of tectonic stresses and fractures. The workflow to set up and calibrate a geomechanical reservoir model includes import of the subsurface geometry as well as assignment of mechanical properties and boundary conditions. If well data are available, calculated stresses and fractures can be calibrated against observed data. Modeling results are relevant for a variety of tasks ranging from borehole stability and fault slip analysis to planning of hydraulic fracs. Application to a data set from a reservoir in the Eastern Sirte basin of Libya illustrates the practical potential of the modelling approach. The case study shows that stress orientations including local perturbations can be predicted with considerable accuracy even if the reservoir and fault geometries are primarily derived from seismic data, i.e. if well data is sparse. By nature, fracture prediction is less robust as it has to build on several poorly constrained input parameters like magnitude and orientation of paleo-stresses, paleo-pore pressures and former rock mechanical properties. Consequently, sufficient well data with fracture orientations observed on borehole image logs are required to calibrate the geomechanical model and provide a reliable base for fracture prognoses in the inter-well space. (orig.)

  6. Daily reservoir inflow forecasting using multiscale deep feature learning with hybrid models

    Science.gov (United States)

    Bai, Yun; Chen, Zhiqiang; Xie, Jingjing; Li, Chuan

    2016-01-01

    Inflow forecasting applies data supports for the operations and managements of reservoirs. A multiscale deep feature learning (MDFL) method with hybrid models is proposed in this paper to deal with the daily reservoir inflow forecasting. Ensemble empirical mode decomposition and Fourier spectrum are first employed to extract multiscale (trend, period and random) features, which are then represented by three deep belief networks (DBNs), respectively. The weights of each DBN are subsequently applied to initialize a neural network (D-NN). The outputs of the three-scale D-NNs are finally reconstructed using a sum-up strategy toward the forecasting results. A historical daily inflow series (from 1/1/2000 to 31/12/2012) of the Three Gorges reservoir, China, is investigated by the proposed MDFL with hybrid models. For comparison, four peer models are adopted for the same task. The results show that, the present model overwhelms all the peer models in terms of mean absolute percentage error (MAPE = 11.2896%), normalized root-mean-square error (NRMSE = 0.2292), determination coefficient criteria (R2 = 0.8905), and peak percent threshold statistics (PPTS(5) = 10.0229%). The addressed method integrates the deep framework with multiscale and hybrid observations, and therefore being good at exploring sophisticated natures in the reservoir inflow forecasting.

  7. A simple multistage closed-(box+reservoir model of chemical evolution

    Directory of Open Access Journals (Sweden)

    Caimmi R.

    2011-01-01

    Full Text Available Simple closed-box (CB models of chemical evolution are extended on two respects, namely (i simple closed-(box+reservoir (CBR models allowing gas outflow from the box into the reservoir (Hartwick 1976 or gas inflow into the box from the reservoir (Caimmi 2007 with rate proportional to the star formation rate, and (ii simple multistage closed-(box+reservoir (MCBR models allowing different stages of evolution characterized by different inflow or outflow rates. The theoretical differential oxygen abundance distribution (TDOD predicted by the model maintains close to a continuous broken straight line. An application is made where a fictitious sample is built up from two distinct samples of halo stars and taken as representative of the inner Galactic halo. The related empirical differential oxygen abundance distribution (EDOD is represented, to an acceptable extent, as a continuous broken line for two viable [O/H]-[Fe/H] empirical relations. The slopes and the intercepts of the regression lines are determined, and then used as input parameters to MCBR models. Within the errors (-+σ, regression line slopes correspond to a large inflow during the earlier stage of evolution and to low or moderate outflow during the subsequent stages. A possible inner halo - outer (metal-poor bulge connection is also briefly discussed. Quantitative results cannot be considered for applications to the inner Galactic halo, unless selection effects and disk contamination are removed from halo samples, and discrepancies between different oxygen abundance determination methods are explained.

  8. 3D model tools for architecture and archaeology reconstruction

    Science.gov (United States)

    Vlad, Ioan; Herban, Ioan Sorin; Stoian, Mircea; Vilceanu, Clara-Beatrice

    2016-06-01

    The main objective of architectural and patrimonial survey is to provide a precise documentation of the status quo of the surveyed objects (monuments, buildings, archaeological object and sites) for preservation and protection, for scientific studies and restoration purposes, for the presentation to the general public. Cultural heritage documentation includes an interdisciplinary approach having as purpose an overall understanding of the object itself and an integration of the information which characterize it. The accuracy and the precision of the model are directly influenced by the quality of the measurements realized on field and by the quality of the software. The software is in the process of continuous development, which brings many improvements. On the other side, compared to aerial photogrammetry, close range photogrammetry and particularly architectural photogrammetry is not limited to vertical photographs with special cameras. The methodology of terrestrial photogrammetry has changed significantly and various photographic acquisitions are widely in use. In this context, the present paper brings forward a comparative study of TLS (Terrestrial Laser Scanner) and digital photogrammetry for 3D modeling. The authors take into account the accuracy of the 3D models obtained, the overall costs involved for each technology and method and the 4th dimension - time. The paper proves its applicability as photogrammetric technologies are nowadays used at a large scale for obtaining the 3D model of cultural heritage objects, efficacious in their assessment and monitoring, thus contributing to historic conservation. Its importance also lies in highlighting the advantages and disadvantages of each method used - very important issue for both the industrial and scientific segment when facing decisions such as in which technology to invest more research and funds.

  9. Optimization of Forward Wave Modeling on Contemporary HPC Architectures

    Energy Technology Data Exchange (ETDEWEB)

    Krueger, Jens [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Micikevicius, Paulius [NVIDIA, Santa Clara, CA (United States); Williams, Samuel [Fraunhofer ITWM, Kaiserslautern (Germany)

    2012-07-20

    Reverse Time Migration (RTM) is one of the main approaches in the seismic processing industry for imaging the subsurface structure of the Earth. While RTM provides qualitative advantages over its predecessors, it has a high computational cost warranting implementation on HPC architectures. We focus on three progressively more complex kernels extracted from RTM: for isotropic (ISO), vertical transverse isotropic (VTI) and tilted transverse isotropic (TTI) media. In this work, we examine performance optimization of forward wave modeling, which describes the computational kernels used in RTM, on emerging multi- and manycore processors and introduce a novel common subexpression elimination optimization for TTI kernels. We compare attained performance and energy efficiency in both the single-node and distributed memory environments in order to satisfy industry’s demands for fidelity, performance, and energy efficiency. Moreover, we discuss the interplay between architecture (chip and system) and optimizations (both on-node computation) highlighting the importance of NUMA-aware approaches to MPI communication. Ultimately, our results show we can improve CPU energy efficiency by more than 10× on Magny Cours nodes while acceleration via multiple GPUs can surpass the energy-efficient Intel Sandy Bridge by as much as 3.6×.

  10. Modelling Spiking Neural Network from the Architecture Evaluation Perspective

    Institute of Scientific and Technical Information of China (English)

    Yu Ji; You-Hui Zhang; Wei-Min Zheng

    2016-01-01

    The brain-inspired spiking neural network (SNN) computing paradigm offers the potential for low-power and scalable computing, suited to many intelligent tasks that conventional computational systems find difficult. On the other hand, NoC (network-on-chips) based very large scale integration (VLSI) systems have been widely used to mimic neuro-biological architectures (including SNNs). This paper proposes an evaluation methodology for SNN applications from the aspect of micro-architecture. First, we extract accurate SNN models from existing simulators of neural systems. Second, a cycle-accurate NoC simulator is implemented to execute the aforementioned SNN applications to get timing and energy-consumption information. We believe this method not only benefits the exploration of NoC design space but also bridges the gap between applications (especially those from the neuroscientists’ community) and neuromorphic hardware. Based on the method, we have evaluated some typical SNNs in terms of timing and energy. The method is valuable for the development of neuromorphic hardware and applications.

  11. Architectures drawn / digital models: the Venices (impossible on line

    Directory of Open Access Journals (Sweden)

    Malvina Borgherini

    2011-12-01

    Full Text Available A contemporary city representation talks not only about architecture and landscape but also about the effects that political institutions, cultural traditions and economic enterprises have on the urban community. Methods and ways traditionally used to present the complexity and, at the same time, the personality of a town, or on a smaller scale of one of his monument, are not suitable with the contemporary reality. A very famous panel presented at Venice Biennale in 1976, Aldo Rossi’s «Città Analoga», within real and ideal architectures, ancient monuments and contemporary landscapes, individual and collective memories, human presences and empty spaces, can be taken as an example for the preparation of a new ‘story’ or a new ‘map’ for a city like Venice. The space of a digital model can become a place for discussion and analysis, a place where to see together historical records and projects never realized, where to put subjective and objective visions, which overlap daily and occasional tracks.

  12. Numerical modeling of fracking fluid and methane migration through fault zones in shale gas reservoirs

    Science.gov (United States)

    Taherdangkoo, Reza; Tatomir, Alexandru; Sauter, Martin

    2017-04-01

    Hydraulic fracturing operation in shale gas reservoir has gained growing interest over the last few years. Groundwater contamination is one of the most important environmental concerns that have emerged surrounding shale gas development (Reagan et al., 2015). The potential impacts of hydraulic fracturing could be studied through the possible pathways for subsurface migration of contaminants towards overlying aquifers (Kissinger et al., 2013; Myers, 2012). The intent of this study is to investigate, by means of numerical simulation, two failure scenarios which are based on the presence of a fault zone that penetrates the full thickness of overburden and connect shale gas reservoir to aquifer. Scenario 1 addresses the potential transport of fracturing fluid from the shale into the subsurface. This scenario was modeled with COMSOL Multiphysics software. Scenario 2 deals with the leakage of methane from the reservoir into the overburden. The numerical modeling of this scenario was implemented in DuMux (free and open-source software), discrete fracture model (DFM) simulator (Tatomir, 2012). The modeling results are used to evaluate the influence of several important parameters (reservoir pressure, aquifer-reservoir separation thickness, fault zone inclination, porosity, permeability, etc.) that could affect the fluid transport through the fault zone. Furthermore, we determined the main transport mechanisms and circumstances in which would allow frack fluid or methane migrate through the fault zone into geological layers. The results show that presence of a conductive fault could reduce the contaminant travel time and a significant contaminant leakage, under certain hydraulic conditions, is most likely to occur. Bibliography Kissinger, A., Helmig, R., Ebigbo, A., Class, H., Lange, T., Sauter, M., Heitfeld, M., Klünker, J., Jahnke, W., 2013. Hydraulic fracturing in unconventional gas reservoirs: risks in the geological system, part 2. Environ Earth Sci 70, 3855

  13. Integrated Reflection Seismic Monitoring and Reservoir Modeling for Geologic CO2 Sequestration

    Energy Technology Data Exchange (ETDEWEB)

    John Rogers

    2011-12-31

    The US DOE/NETL CCS MVA program funded a project with Fusion Petroleum Technologies Inc. (now SIGMA) to model the proof of concept of using sparse seismic data in the monitoring of CO{sub 2} injected into saline aquifers. The goal of the project was to develop and demonstrate an active source reflection seismic imaging strategy based on deployment of spatially sparse surface seismic arrays. The primary objective was to test the feasibility of sparse seismic array systems to monitor the CO{sub 2} plume migration injected into deep saline aquifers. The USDOE/RMOTC Teapot Dome (Wyoming) 3D seismic and reservoir data targeting the Crow Mountain formation was used as a realistic proxy to evaluate the feasibility of the proposed methodology. Though the RMOTC field has been well studied, the Crow Mountain as a saline aquifer has not been studied previously as a CO{sub 2} sequestration (storage) candidate reservoir. A full reprocessing of the seismic data from field tapes that included prestack time migration (PSTM) followed by prestack depth migration (PSDM) was performed. A baseline reservoir model was generated from the new imaging results that characterized the faults and horizon surfaces of the Crow Mountain reservoir. The 3D interpretation was integrated with the petrophysical data from available wells and incorporated into a geocellular model. The reservoir structure used in the geocellular model was developed using advanced inversion technologies including Fusion's ThinMAN{trademark} broadband spectral inversion. Seal failure risk was assessed using Fusion's proprietary GEOPRESS{trademark} pore pressure and fracture pressure prediction technology. CO{sub 2} injection was simulated into the Crow Mountain with a commercial reservoir simulator. Approximately 1.2MM tons of CO{sub 2} was simulated to be injected into the Crow Mountain reservoir over 30 years and subsequently let 'soak' in the reservoir for 970 years. The relatively small plume

  14. Coupling of Thermal-Hydraulic-Mechanical Processes for Geothermal Reservoir Modelling

    Institute of Scientific and Technical Information of China (English)

    Ali Karrechl Oussama Beltaief; Ruyan Vincec; Thomas Poulet; Klaus Regenauer-Lieb

    2015-01-01

    This paper uses a fully coupled framework of thermal-hydraulic-mechanical processes to investigate how the injection and extraction of fluid within a geothermal reservoir impacts on the dis-tributions of temperature, pore pressure, and deformation within the rock formations. Based on this formulation, a numerical model is developed in light of the thermodynamics of porous materials. The proposed procedure relies on the derivation of dissipative flow rules by postulating proper storage and dissipation functions. This approach opens new horizons for several resource engineering applications. Since it allows for full coupling, this formulation can play a key role in predicting risks when used for reservoir simulation. The results indicate that the injection-extraction process and temperature change have a definite impact on altering the in-situ properties of the reservoir.

  15. Model-based workflows for optimal long-term reservoir mangement

    NARCIS (Netherlands)

    Leeuwenburgh, O.; Egberts, P.; Chitu, A.; Wilschut, F.

    2014-01-01

    Life-cycle optimization is the process of finding field operation strategies that aim to optimize recovery or economic value with a long-term (years to decades) horizon. A reservoir simulation model is therefore generally appropriate and sufficient to explore the impact of different recovery

  16. Java Architecture for Detect and Avoid Extensibility and Modeling

    Science.gov (United States)

    Santiago, Confesor; Mueller, Eric Richard; Johnson, Marcus A.; Abramson, Michael; Snow, James William

    2015-01-01

    Unmanned aircraft will equip with a detect-and-avoid (DAA) system that enables them to comply with the requirement to "see and avoid" other aircraft, an important layer in the overall set of procedural, strategic and tactical separation methods designed to prevent mid-air collisions. This paper describes a capability called Java Architecture for Detect and Avoid Extensibility and Modeling (JADEM), developed to prototype and help evaluate various DAA technological requirements by providing a flexible and extensible software platform that models all major detect-and-avoid functions. Figure 1 illustrates JADEM's architecture. The surveillance module can be actual equipment on the unmanned aircraft or simulators that model the process by which sensors on-board detect other aircraft and provide track data to the traffic display. The track evaluation function evaluates each detected aircraft and decides whether to provide an alert to the pilot and its severity. Guidance is a combination of intruder track information, alerting, and avoidance/advisory algorithms behind the tools shown on the traffic display to aid the pilot in determining a maneuver to avoid a loss of well clear. All these functions are designed with a common interface and configurable implementation, which is critical in exploring DAA requirements. To date, JADEM has been utilized in three computer simulations of the National Airspace System, three pilot-in-the-loop experiments using a total of 37 professional UAS pilots, and two flight tests using NASA's Predator-B unmanned aircraft, named Ikhana. The data collected has directly informed the quantitative separation standard for "well clear", safety case, requirements development, and the operational environment for the DAA minimum operational performance standards. This work was performed by the Separation Assurance/Sense and Avoid Interoperability team under NASA's UAS Integration in the NAS project.

  17. Model Tests for Shallow-Water Ship Maneuverability in Three Gorges Reservoir

    Directory of Open Access Journals (Sweden)

    Cai Chuang

    2015-09-01

    Full Text Available This paper conducts calibration tests on the shallow-water maneuverability of 1:100 ship models for the typical navigation fleets in Three Gorges Reservoir. Major influential factors for the maneuverability similitude between models and prototypes and for scale effect were identified. A correction method for model scale was also established through model tests. Test results indicate that, by correcting the model scales of various fleets based on scale effect, the maneuverability indexes K’ (dimensionless of K and T’ (dimensionless of T of ship models are suitable for shallow-water tests, and properly reflect the maneuvering characteristics of prototypes. The findings provide an experimental basis for the navigation safety in Three Gorges Reservoir.

  18. Probabilistic model for vessel-bridge collisions in the Three Gorges Reservoir

    Institute of Scientific and Technical Information of China (English)

    Bo GENG; Hong WANG; Junjie WANG

    2009-01-01

    Based on a field observation on vessel transit path of three bridges over the Yangtze River in the Three Gorges Reservoir, and an analysis of the geometric probabilistic model of transiting vessels in collision probability calculation, the aberrancy angle and vessel velocity probabilistic model related with impact force, a probabilistic model is established and also verified by goodness-of-fit test. The vessel transit path distribution can be expressed by the normal distribution model. For the Three Gorges Reservoir, the mean and standard deviation adopt 0.2w and 0.1w, respectively (w is the channel width).The aberrancy angle distribution of vessels accepts maximum I distribution model, and its distribution parameters can be taken as 0.314 and 4.354. The velocity distribution of up-bound and down-bound vessels can also be expressed by the normal distribution model.

  19. Geological modeling for methane hydrate reservoir characterization in the eastern Nankai Trough, offshore Japan

    Science.gov (United States)

    Tamaki, M.; Komatsu, Y.; Suzuki, K.; Takayama, T.; Fujii, T.

    2012-12-01

    The eastern Nankai trough, which is located offshore of central Japan, is considered as an attractive potential resource field of methane hydrates. Japan Oil, Gas and Metals National Corporation is planning to conduct a production test in early 2013 at the AT1 site in the north slope of Daini-Atsumi Knoll in the eastern Nankai Trough. The depositional environment of methane hydrate-bearing sediments around the production test site is a deep submarine-fan turbidite system, and it is considered that the reservoir properties should show lateral as well as vertical heterogeneity. Since the variations in the reservoir heterogeneity have an impact on the methane hydrate dissociation and gas production performance, precise geological models describing reservoir heterogeneity would be required for the evaluation of reservoir potentials. In preparation for the production test, 3 wells; two monitoring boreholes (AT1-MC and AT1-MT1) and a coring well (AT1-C), were newly acquired in 2012. In addition to a geotechnical hole drilling survey in 2011 (AT1-GT), totally log data from 2 wells and core data from 2 wells were obtained around the production test site. In this study, we conducted well correlations between AT1 and A1 wells drilled in 2003 and then, 3D geological models were updated including AT1 well data in order to refine hydrate reservoir characterization around the production test site. The results of the well correlations show that turbidite sand layers are characterized by good lateral continuity, and give significant information for the distribution morphology of sand-rich channel fills. We also reviewed previously conducted 3D geological models which consist of facies distributions and petrophysical properties distributions constructed from integration of 3D seismic data and a well data (A1 site) adopting a geostatistical approach. In order to test the practical validity of the previously generated models, cross-validation was conducted using AT1 well data. The

  20. Model design for predicting extreme precipitation event impacts on water quality in a water supply reservoir

    Science.gov (United States)

    Hagemann, M.; Jeznach, L. C.; Park, M. H.; Tobiason, J. E.

    2016-12-01

    Extreme precipitation events such as tropical storms and hurricanes are by their nature rare, yet have disproportionate and adverse effects on surface water quality. In the context of drinking water reservoirs, common concerns of such events include increased erosion and sediment transport and influx of natural organic matter and nutrients. As part of an effort to model the effects of an extreme precipitation event on water quality at the reservoir intake of a major municipal water system, this study sought to estimate extreme-event watershed responses including streamflow and exports of nutrients and organic matter for use as inputs to a 2-D hydrodynamic and water quality reservoir model. Since extreme-event watershed exports are highly uncertain, we characterized and propagated predictive uncertainty using a quasi-Monte Carlo approach to generate reservoir model inputs. Three storm precipitation depths—corresponding to recurrence intervals of 5, 50, and 100 years—were converted to streamflow in each of 9 tributaries by volumetrically scaling 2 storm hydrographs from the historical record. Rating-curve models for concentratoin, calibrated using 10 years of data for each of 5 constituents, were then used to estimate the parameters of a multivariate lognormal probability model of constituent concentrations, conditional on each scenario's storm date and streamflow. A quasi-random Halton sequence (n = 100) was drawn from the conditional distribution for each event scenario, and used to generate input files to a calibrated CE-QUAL-W2 reservoir model. The resulting simulated concentrations at the reservoir's drinking water intake constitute a low-discrepancy sample from the estimated uncertainty space of extreme-event source water-quality. Limiting factors to the suitability of this approach include poorly constrained relationships between hydrology and constituent concentrations, a high-dimensional space from which to generate inputs, and relatively long run

  1. Application of Discrete Fracture Modeling and Upscaling Techniques to Complex Fractured Reservoirs

    Science.gov (United States)

    Karimi-Fard, M.; Lapene, A.; Pauget, L.

    2012-12-01

    During the last decade, an important effort has been made to improve data acquisition (seismic and borehole imaging) and workflow for reservoir characterization which has greatly benefited the description of fractured reservoirs. However, the geological models resulting from the interpretations need to be validated or calibrated against dynamic data. Flow modeling in fractured reservoirs remains a challenge due to the difficulty of representing mass transfers at different heterogeneity scales. The majority of the existing approaches are based on dual continuum representation where the fracture network and the matrix are represented separately and their interactions are modeled using transfer functions. These models are usually based on idealized representation of the fracture distribution which makes the integration of real data difficult. In recent years, due to increases in computer power, discrete fracture modeling techniques (DFM) are becoming popular. In these techniques the fractures are represented explicitly allowing the direct use of data. In this work we consider the DFM technique developed by Karimi-Fard et al. [1] which is based on an unstructured finite-volume discretization. The mass flux between two adjacent control-volumes is evaluated using an optimized two-point flux approximation. The result of the discretization is a list of control-volumes with the associated pore-volumes and positions, and a list of connections with the associated transmissibilities. Fracture intersections are simplified using a connectivity transformation which contributes considerably to the efficiency of the methodology. In addition, the method is designed for general purpose simulators and any connectivity based simulator can be used for flow simulations. The DFM technique is either used standalone or as part of an upscaling technique. The upscaling techniques are required for large reservoirs where the explicit representation of all fractures and faults is not possible

  2. Automatic Texture Mapping of Architectural and Archaeological 3d Models

    Science.gov (United States)

    Kersten, T. P.; Stallmann, D.

    2012-07-01

    Today, detailed, complete and exact 3D models with photo-realistic textures are increasingly demanded for numerous applications in architecture and archaeology. Manual texture mapping of 3D models by digital photographs with software packages, such as Maxon Cinema 4D, Autodesk 3Ds Max or Maya, still requires a complex and time-consuming workflow. So, procedures for automatic texture mapping of 3D models are in demand. In this paper two automatic procedures are presented. The first procedure generates 3D surface models with textures by web services, while the second procedure textures already existing 3D models with the software tmapper. The program tmapper is based on the Multi Layer 3D image (ML3DImage) algorithm and developed in the programming language C++. The studies showing that the visibility analysis using the ML3DImage algorithm is not sufficient to obtain acceptable results of automatic texture mapping. To overcome the visibility problem the Point Cloud Painter algorithm in combination with the Z-buffer-procedure will be applied in the future.

  3. Intermittent reservoir daily-inflow prediction using lumped and distributed data multi-linear regression models

    Indian Academy of Sciences (India)

    R B Magar; V Jothiprakash

    2011-12-01

    In this study, multi-linear regression (MLR) approach is used to construct intermittent reservoir daily inflow forecasting system. To illustrate the applicability and effect of using lumped and distributed input data in MLR approach, Koyna river watershed in Maharashtra, India is chosen as a case study. The results are also compared with autoregressive integrated moving average (ARIMA) models. MLR attempts to model the relationship between two or more independent variables over a dependent variable by fitting a linear regression equation. The main aim of the present study is to see the consequences of development and applicability of simple models, when sufficient data length is available. Out of 47 years of daily historical rainfall and reservoir inflow data, 33 years of data is used for building the model and 14 years of data is used for validating the model. Based on the observed daily rainfall and reservoir inflow, various types of time-series, cause-effect and combined models are developed using lumped and distributed input data. Model performance was evaluated using various performance criteria and it was found that as in the present case, of well correlated input data, both lumped and distributed MLR models perform equally well. For the present case study considered, both MLR and ARIMA models performed equally sound due to availability of large dataset.

  4. A new approach to integrate seismic and production data in reservoir models

    Energy Technology Data Exchange (ETDEWEB)

    Ouenes, A.; Chawathe, A.; Weiss, W. [New Mexico Tech, Socorro, NM (United States)] [and others

    1997-08-01

    A great deal of effort is devoted to reducing the uncertainties in reservoir modeling. For example, seismic properties are used to improve the characterization of interwell properties by providing porosity maps constrained to seismic impedance. Another means to reduce uncertainties is to constrain the reservoir model to production data. This paper describes a new approach where the production and seismic data are simultaneously used to reduce the uncertainties. In this new approach, the primary geologic parameter that controls reservoir properties is identified. Next, the geophysical parameter that is sensitive to the dominant geologic parameter is determined. Then the geology and geophysics are linked using analytic correlations. Unfortunately, the initial guess resulted in a reservoir model that did not match the production history. Since the time required for trial and error matching of production history is exorbitant, an automatic history matching method based on a fast optimization method was used to find the correlating parameters. This new approach was illustrated with an actual field in the Williston Basin. Upscalling problems do not arise since the scale is imposed by the size of the seismic bin (66m, 219 ft) which is the size of the simulator gridblocks.

  5. Productivity Analysis of Volume Fractured Vertical Well Model in Tight Oil Reservoirs

    Directory of Open Access Journals (Sweden)

    Jiahang Wang

    2017-01-01

    Full Text Available This paper presents a semianalytical model to simulate the productivity of a volume fractured vertical well in tight oil reservoirs. In the proposed model, the reservoir is a composite system which contains two regions. The inner region is described as formation with finite conductivity hydraulic fracture network and the flow in fracture is assumed to be linear, while the outer region is simulated by the classical Warren-Root model where radial flow is applied. The transient rate is calculated, and flow patterns and characteristic flowing periods caused by volume fractured vertical well are analyzed. Combining the calculated results with actual production data at the decline stage shows a good fitting performance. Finally, the effects of some sensitive parameters on the type curves are also analyzed extensively. The results demonstrate that the effect of fracture length is more obvious than that of fracture conductivity on improving production in tight oil reservoirs. When the length and conductivity of main fracture are constant, the contribution of stimulated reservoir volume (SRV to the cumulative oil production is not obvious. When the SRV is constant, the length of fracture should also be increased so as to improve the fracture penetration and well production.

  6. Maximum Effective Hole Mathematical Model and Exact Solution for Commingled Reservoir

    Institute of Scientific and Technical Information of China (English)

    孙贺东; 刘磊; 周芳德; 高承泰

    2003-01-01

    The maximum effective hole-diameter mathematical model describing the flow of slightly compressible fluid through a commingled reservoir was solved rigorously with consideration of wellbore storage and different skin factors. The exact solutions for wellbore pressure and the production rate obtained from layer j for a well production at a constant rate from a radial drainage area with infinite and constant pressure and no flow outer boundary condition were expressed in terms of ordinary Bessel functions. These solutions were computed numerically by the Crump''s numerical inversion method and the behavior of systems was studied as a function of various reservoir parameters. The model was compared with the real wellbore radii model. The new model is numerically stable when the skin factor is positive and negative, but the real wellbore radii model is numerically stable only when the skin factor is positive.

  7. Mosque as a Model of Learning Principles of Sustainable Architecture

    Directory of Open Access Journals (Sweden)

    Swambodo Murdariatmo Adi

    2016-06-01

    Full Text Available The mosque is an integral part of the circuit-worship rituals of Islam. For Muslims in Indonesia, the role of the mosque as a place of worship, examines religion and some other activities occupy a strategic position not only as a religious symbol but more emphasis on the function of the space as a public building. Utilization of space in public buildings as well as space-ritual-social space will have meaning for the people in view of adaptation space used. Awareness of the importance of effective space utilization and management of water resources wisely in support of the ritual apply the principles of sustainable architecture will have a positive impact for the people to give directions as to how the principle of austerity-not wasteful in Islam can be applied. This paper will discuss about the process of continuous learning from the essence of understanding of the mosque as a model in implementing the process of life, taking into account the principles of simplicity, functional and wisdom, especially in the efficiency of utilization of local resources. The method used in this research is qualitative descriptive, which is explained the theory and based on literature and accompanied by case study that have implemented the principles. The output of this application of the principles of sustainable architecture in the planning and use of mosques as a place in the relationship with God and with fellow human relations can be a model for the faithful to deal with wisely challenge natural resource constraints, especially for future generations.

  8. Executable Behavioral Modeling of System and Software Architecture Specifications to Inform Resourcing Decisions

    Science.gov (United States)

    2016-09-01

    BEHAVIORAL MODELING OF SYSTEM- AND SOFTWARE-ARCHITECTURE SPECIFICATIONS TO INFORM RESOURCING DECISIONS by Monica F. Farah-Stapleton...REPORT DATE September 2016 3. REPORT TYPE AND DATES COVERED Doctoral Dissertation 4. TITLE AND SUBTITLE EXECUTABLE BEHAVIORAL MODELING OF SYSTEM...intellectual, programmatic, and organizational resources. Precise behavioral modeling offers a way to assess architectural design decisions prior to

  9. River and Reservoir Operations Model, Truckee River basin, California and Nevada, 1998

    Science.gov (United States)

    Berris, Steven N.; Hess, Glen W.; Bohman, Larry R.

    2001-01-01

    The demand for all uses of water in the Truckee River Basin, California and Nevada, commonly is greater than can be supplied. Storage reservoirs in the system have a maximum effective total capacity equivalent to less than two years of average river flows, so longer-term droughts can result in substantial water-supply shortages for irrigation and municipal users and may stress fish and wildlife ecosystems. Title II of Public Law (P.L.) 101-618, the Truckee?Carson?Pyramid Lake Water Rights Settlement Act of 1990, provides a foundation for negotiating and developing operating criteria, known as the Truckee River Operating Agreement (TROA), to balance interstate and interbasin allocation of water rights among the many interests competing for water from the Truckee River. In addition to TROA, the Truckee River Water Quality Settlement Agreement (WQSA), signed in 1996, provides for acquisition of water rights to resolve water-quality problems during low flows along the Truckee River in Nevada. Efficient execution of many of the planning, management, or environmental assessment requirements of TROA and WQSA will require detailed water-resources data coupled with sound analytical tools. Analytical modeling tools constructed and evaluated with such data could help assess effects of alternative operational scenarios related to reservoir and river operations, water-rights transfers, and changes in irrigation practices. The Truckee?Carson Program of the U.S. Geological Survey, to support U.S. Department of the Interior implementation of P.L. 101-618, is developing a modeling system to support efficient water-resources planning, management, and allocation. The daily operations model documented herein is a part of the modeling system that includes a database management program, a graphical user interface program, and a program with modules that simulate river/reservoir operations and a variety of hydrologic processes. The operations module is capable of simulating lake

  10. Applications of GSTARS Computer Models for Solving River and Reservoir Sedimentation Problems

    Institute of Scientific and Technical Information of China (English)

    YANG Chih Ted

    2008-01-01

    GSTARS (Generalized Sediment Transport model for Alluvial River Simulation) is a series of computer models developed by the U.S. Bureau of Reclamation while the author was employed by that agency. The stream tube concept is used in all GSTARS models which allow us to solve one-dimensional equations for each stream tube independently and obtain semi-two-dimensional variation of the hydraulic conditions along and across stream tubes for rivers and reservoirs. Sedi-ment transport, scour, and deposition processes are simulated along each stream tube independ-ently to give us a semi-three-dimensional variation of the bed geometry. Most sediment transport computer models assume that channel width is given and cannot change during the simulation process. GSTARS models apply the theory of minimum stream power to the determination of op-timum channel width and channel geometry. The concepts of channel side stability, and active,inactive, and armoring layers are used in all GSTARS models for realistic long-term simulation and prediction of the scour and deposition processes in rivers and reservoirs.GSTARS models have been applied in many countries for solving a wide range of river and reservoir sedimentation prob-lems. Case studies will be used to illustrate the applications of GSTARS computer models.

  11. A COUPLED MODEL OF HYDRODYNAMICS AND WATER QUALITY FOR YUQIAO RESERVOIR IN HAIHE RIVER BASIN

    Institute of Scientific and Technical Information of China (English)

    LIU Xiao-bo; PENG Wen-qi; HE Guo-jian; LIU Jing-ling; WANG Yu-chun

    2008-01-01

    In order to simulate the characteristics of hydrodynamic field and mass transport processes in the Yuqiao Reservoir (YQR), a 2-D coupled model of hydrodynamics and water quality was developed, and the water-quality related state variables in this model included CODMn, TN and TP. The hydrodynamic model was driven by employing observed winds and daily measured flow data to simulate the seasonal water cycle of the reservoir. The simulation of the mass transport and transformation processes of CODMn, TN and TP was based on the unsteady diffusion equations, driven by observed meteorological forcing and external Ioadings, with the fluxes form the bottom of reservoir and the plant photosynthesis and respiration as internal sources and sinks. A finite volume method and Alternating Direction Implicit (ADI) scheme were used to solve these equations. The model was calibrated and verified by using the data observed from YQR in two different years. The results showed that in YQR, the wind-driven current was an important style of lake current, while the concentration of water quality item was decreasing from east to west because of the external pollutant loadings. There was a good agreement between the simulated and measured values, with the minimal calculation error percent of 0.1% and 2.6% and the mean error percent of 44.0% and 51.2% for TN and TP separately. The simulation also showed that, in YQR, the convection was the main process in estuaries of inflow river, and diffusion and biochemical processes dominate in center of reservoir. So it was necessary to build a pre-pond to reduce the external Ioadings into the reservoir.

  12. A Model for Information Integration Using Service Oriented Architectur

    Directory of Open Access Journals (Sweden)

    C. Punitha Devi

    2014-06-01

    Full Text Available Business agility remains to be the keyword that drives the business into different directions and enabling a 360 degree shift in the business process. To achieve agility the organization should work on real time information and data. The need to have instant access to information appears to be ever shine requirement of all organizations or enterprise. Access to information does not come directly with a single query but a complex process termed Information integration. Information integration has been in existence for the past two decades and has been progressive up to now. The challenges and issues keep on persisting as information integration problem evolves by itself. This paper addresses the issues in the approaches, techniques and models pertaining to information integration and identifies the problem for a need for a complete model. As SOA is the architectural style that is changing the business patterns today, this paper proposes a service oriented model for information integration. The model mainly focuses on giving a complete structure for information integration that is adaptable to any environment and open in nature. Here information is converted into service and then the information services are integrated through service oriented integration to provide the integrated information also as service.

  13. A Secured Hybrid Architecture Model for Internet Banking (e - Banking

    Directory of Open Access Journals (Sweden)

    Ganesan R

    2009-05-01

    Full Text Available Internet banking has made it easy to carry out the personal or business financial trans action without going to bank and at any suitable time. This facility enables to transfer money to other accounts and checking current balance alongside the status of any financial transaction made in the account. However, in order to maintain privacy and t o avoid any misuse of transactions, it is necessary to follow a secured architecture model which ensures the privacy and integrity of the transactions and provides confidence on internet banking is stable. In this research paper, a secured hybrid architect ure model for the internet banking using Hyperelliptic curve cryptosystem and MD5 is described. This hybrid model is implemented with the hyperelliptic curve cryptosystem and it performs the encryption and decryption processes in an efficient way merely wi th an 80 - bit key size. The various screen shots given in this contribution shows that the hybrid model which encompasses HECC and MD5 can be considered in the internet banking environment to enrich the privacy and integrity of the sensitive data transmitte d between the clients and the application server

  14. Organizational information assets classification model and security architecture methodology

    Directory of Open Access Journals (Sweden)

    Mostafa Tamtaji

    2015-12-01

    Full Text Available Today's, Organizations are exposed with huge and diversity of information and information assets that are produced in different systems shuch as KMS, financial and accounting systems, official and industrial automation sysytems and so on and protection of these information is necessary. Cloud computing is a model for enabling ubiquitous, convenient, on-demand network access to a shared pool of configurable computing resources that can be rapidly provisioned and released.several benefits of this model cuses that organization has a great trend to implementing Cloud computing. Maintaining and management of information security is the main challenges in developing and accepting of this model. In this paper, at first, according to "design science research methodology" and compatible with "design process at information systems research", a complete categorization of organizational assets, including 355 different types of information assets in 7 groups and 3 level, is presented to managers be able to plan corresponding security controls according to importance of each groups. Then, for directing of organization to architect it’s information security in cloud computing environment, appropriate methodology is presented. Presented cloud computing security architecture , resulted proposed methodology, and presented classification model according to Delphi method and expers comments discussed and verified.

  15. 3-D Reservoir and Stochastic Fracture Network Modeling for Enhanced Oil Recovery, Circle Ridge Phosphoria/Tensleep Reservoir, and River Reservation, Arapaho and Shoshone Tribes, Wyoming

    Energy Technology Data Exchange (ETDEWEB)

    La Pointe, Paul R.; Hermanson, Jan

    2002-09-09

    The goal of this project is to improve the recovery of oil from the Circle Ridge Oilfield, located on the Wind River Reservation in Wyoming, through an innovative integration of matrix characterization, structural reconstruction, and the characterization of the fracturing in the reservoir through the use of discrete fracture network models.

  16. Reservoir Modeling Combining Geostatistics with Markov Chain Monte Carlo Inversion

    DEFF Research Database (Denmark)

    Zunino, Andrea; Lange, Katrine; Melnikova, Yulia;

    2014-01-01

    , multi-step forward model (rock physics and seismology) and to provide realistic estimates of uncertainties. To generate realistic models which represent samples of the prior distribution, and to overcome the high computational demand, we reduce the search space utilizing an algorithm drawn from...

  17. Modeling lakes and reservoirs in the climate system

    NARCIS (Netherlands)

    MacKay, M.D.; Neale, P.J.; Arp, C.D.; De Senerpont Domis, L.N.; Fang, X.; Gal, G.; Jöhnk, K.D.; Kirillin, G.; Lenters, J.D.; Litchman, E.; MacIntyre, S.; Marsh, P.; Melack, J.; Mooij, W.M.; Peeters, F.; Quesada, A.; Schladow, S.G.; Schmid, M.; Spence, C.; Stokes, S.L.

    2009-01-01

    Modeling studies examining the effect of lakes on regional and global climate, as well as studies on the influence of climate variability and change on aquatic ecosystems, are surveyed. Fully coupled atmosphere–land surface–lake climate models that could be used for both of these types of study simu

  18. Geochemical modeling of diagenetic reactions in Snorre Field reservoir sandstones: a comparative study of computer codes

    Directory of Open Access Journals (Sweden)

    Marcos Antonio Klunk

    Full Text Available ABSTRACTDiagenetic reactions, characterized by the dissolution and precipitation of minerals at low temperatures, control the quality of sedimentary rocks as hydrocarbon reservoirs. Geochemical modeling, a tool used to understand diagenetic processes, is performed through computer codes based on thermodynamic and kinetic parameters. In a comparative study, we reproduced the diagenetic reactions observed in Snorre Field reservoir sandstones, Norwegian North Sea. These reactions had been previously modeled in the literature using DISSOL-THERMAL code. In this study, we modeled the diagenetic reactions in the reservoirs using Geochemist's Workbench (GWB and TOUGHREACT software, based on a convective-diffusive-reactive model and on the thermodynamic and kinetic parameters compiled for each reaction. TOUGHREACT and DISSOL-THERMAL modeling showed dissolution of quartz, K-feldspar and plagioclase in a similar temperature range from 25 to 80°C. In contrast, GWB modeling showed dissolution of albite, plagioclase and illite, as well as precipitation of quartz, K-feldspar and kaolinite in the same temperature range. The modeling generated by the different software for temperatures of 100, 120 and 140°C showed similarly the dissolution of quartz, K-feldspar, plagioclase and kaolinite, but differed in the precipitation of albite and illite. At temperatures of 150 and 160°C, GWB and TOUGHREACT produced different results from the DISSOL-THERMAL, except for the dissolution of quartz, plagioclase and kaolinite. The comparative study allows choosing the numerical modeling software whose results are closer to the diagenetic reactions observed in the petrographic analysis of the modeled reservoirs.

  19. Modeling lakes and reservoirs in the climate system

    Science.gov (United States)

    MacKay, M.D.; Neale, P.J.; Arp, C.D.; De Senerpont Domis, L. N.; Fang, X.; Gal, G.; Jo, K.D.; Kirillin, G.; Lenters, J.D.; Litchman, E.; MacIntyre, S.; Marsh, P.; Melack, J.; Mooij, W.M.; Peeters, F.; Quesada, A.; Schladow, S.G.; Schmid, M.; Spence, C.; Stokes, S.L.

    2009-01-01

    Modeling studies examining the effect of lakes on regional and global climate, as well as studies on the influence of climate variability and change on aquatic ecosystems, are surveyed. Fully coupled atmosphere-land surface-lake climate models that could be used for both of these types of study simultaneously do not presently exist, though there are many applications that would benefit from such models. It is argued here that current understanding of physical and biogeochemical processes in freshwater systems is sufficient to begin to construct such models, and a path forward is proposed. The largest impediment to fully representing lakes in the climate system lies in the handling of lakes that are too small to be explicitly resolved by the climate model, and that make up the majority of the lake-covered area at the resolutions currently used by global and regional climate models. Ongoing development within the hydrological sciences community and continual improvements in model resolution should help ameliorate this issue.

  20. A Combined Thermodynamic and Kinetic Model for Barite Prediction at Oil Reservoir Conditions

    DEFF Research Database (Denmark)

    Zhen Wu, Bi Yun

    of the literature (PhD Study 1). The reviewed dataset was used as starting point for geochemical speciation modelling and applied to predict the stability of sulphate minerals in North Sea oil field brines. Second, for modelling of high salinity solutions using the Pitzer ion interaction approach, the temperature......In marine environments, barite (BaSO4) is a key proxy that has been used for understanding the biological and chemical evolution of oceans and for tracking the origin of fluids. In the oil industry, barite scale can clog pipelines and pores in the reservoirs, reducing oil yield. The goal...... of this research was to develop a model, based on thermodynamics and kinetics, for predicting barite precipitation rates in saline waters at the pressures and temperatures of oil bearing reservoirs, using the geochemical modelling code PHREEQC. This task is complicated by the conditions where traditional methods...

  1. 3-D Modeling of Pore Pressure Diffusion Beneath Koyna and Warna Reservoirs, Western India

    Science.gov (United States)

    Yadav, Amrita; Gahalaut, Kalpna; Purnachandra Rao, N.

    2017-03-01

    The mechanism of reservoir-triggered seismicity is well-understood and explains the earthquake occurrence at different reservoir sites. It can be attributed to the stresses due to water loading and to changes in fluid pressure in pores within the rock matrix. In the present study a 3-D fluid flow numerical model is used to investigate the pore pressure diffusion as a cause for continued seismicity in the Koyna-Warna region in western India. It is shown that reservoir water level fluctuations are sufficient to trigger earthquakes at the seismogenic depths in the region. Our numerical model suggests that a vertical fault with hydraulic conductivity in the range 2-6 m/day facilitates the diffusion of pressure at focal depths of earthquakes in the Koyna-Warna region. Also, for triggering of earthquakes a higher vertical conductivity is required for the Warna region than for the Koyna region. A lag of two months period is found between the maximum water level and the significant hydraulic head required to trigger earthquakes at the focal depth using the appropriate hydraulic conductivity for both the reservoirs.

  2. Eutrophication model for river-type reservoir tributaries and its applications

    Institute of Scientific and Technical Information of China (English)

    Ling-ling WANG; Zhen-zhen YU; Hui-chao DAI; Qing-hua CAI

    2009-01-01

    With the impoundment of the Three Gorges Reservoir, algal blooms have been found in some tributaries. In this study, according to the theoretical analysis of the eutrophication mechanismin a river-type reservoir tributary, a one-dimensional eutrophication model was developed for the Xiangxi River tributary of the Three Gorges Reservoir, and the influence of hydrodynamic conditions on the primary growth rate of algae was investigated. Furthermore, numericalpredictions of hydraulic variables and eutrophication factors, such as the concentration distribution of TP, TN, and Chl-a in the spatial and temporal domains, were carded out. Comparison of computation results of TP, TN, and Chl-a concentrations along the river in the spring of 2005 with experimental data demonstrates the validity of the model. The agreement between the computation results and the experimental data of TP and TN concentrations is better than the agreement between those of Chl-a concentration. The simulated results also show that the Chl-a concentration downstream is much higher than that in the upstream tributary, which potentially indicates the outbreak of algae in this area. Therefore, this study provides a feasible method of accurately predicting the state of eutrophication in river-type reservoirs and their tributaries.

  3. Hedging Rules for Water Supply Reservoir Based on the Model of Simulation and Optimization

    Directory of Open Access Journals (Sweden)

    Yi Ji

    2016-06-01

    Full Text Available This study proposes a hedging rule model which is composed of a two-period reservior operation model considering the damage depth and hedging rule parameter optimization model. The former solves hedging rules based on a given poriod’s water supply weighting factor and carryover storage target, while the latter optimization model is used to optimize the weighting factor and carryover storage target based on the hedging rules. The coupling model gives the optimal poriod’s water supply weighting factor and carryover storage target to guide release. The conclusions achieved from this study as follows: (1 the water supply weighting factor and carryover storage target have a direct impact on the three elements of the hedging rule; (2 parameters can guide reservoirs to supply water reasonably after optimization of the simulation and optimization model; and (3 in order to verify the utility of the hedging rule, the Heiquan reservoir is used as a case study and particle swarm optimization algorithm with a simulation model is adopted for optimizing the parameter. The results show that the proposed hedging rule can improve the operation performances of the water supply reservoir.

  4. Coupling of a reservoir model and of a poro-mechanical model. Application to the study of the compaction of petroleum reservoirs and of the associated subsidence; Couplage d'un modele de gisement et d'un modele mecanique. Application a l'etude de la compaction des reservoirs petroliers et de la subsidence associee

    Energy Technology Data Exchange (ETDEWEB)

    Bevillon, D.

    2000-11-30

    The aim of this study is to provide a better description of the rock contribution to fluid flows in petroleum reservoirs. The production of oil/gas in soft highly compacting reservoirs induces important reduction of the pore volume, which increases oil productivity. This compaction leads to undesirable effects such as surface subsidence or damage of well equipment. Analysis of compaction and subsidence can be performed using either engineering reservoir models or coupled poro-mechanical models. Poro-mechanical model offers a rigorous mechanical framework, but does not permit a complete description of the fluids. The reservoir model gives a good description of the fluid phases, but the description of the mechanic phenomenon is then simplified. To satisfy the set of equations (mechanical equilibrium and diffusivity equations), two simulators can be used together sequentially. Each of the two simulators solves its own system independently, and information passed both directions between simulators. This technique is usually referred to the partially coupled scheme. In this study, reservoir and hydro-mechanical simulations show that reservoir theory is not a rigorous framework to represent the evolution of the high porous rocks strains. Then, we introduce a partially coupled scheme that is shown to be consistent and unconditionally stable, which permits to describe correctly poro-mechanical theory in reservoir models. (author)

  5. The application of models to find the relevance of residence time in lake and reservoir management

    Directory of Open Access Journals (Sweden)

    Sven E. JØRGENSEN

    2003-09-01

    Full Text Available The residence time is among the most important factors that determine the water quality of lakes and reservoirs. Models are useful tools to reveal the relationship between the residence time and the water quality. Three case studies are presented to illustrate the application of models to determine the importance of the residence time for the water quality. It was found that manipulation of the residence time, i.e. ecohydrology, may be a very useful environmental management tool.

  6. Ecological Niche Modeling of main reservoir hosts of zoonotic cutaneous leishmaniasis in Iran.

    Science.gov (United States)

    Gholamrezaei, Mostafa; Mohebali, Mehdi; Hanafi-Bojd, Ahmad Ali; Sedaghat, Mohammad Mehdi; Shirzadi, Mohammad Reza

    2016-08-01

    Zoonotic cutaneous leishmaniasis (ZCL), caused by Leishmania major, is a common zoonotic vector-borne disease in Iran. Close contact with infected reservoir hosts increases the probability of transmission of Leishmania parasite infections to susceptible humans. Four gerbil species (Rodentia: Gerbillidae) serve as the main reservoir hosts for ZCL in different endemic foci of Iran. These species include Rhombomys opimus, Meriones libycus, Meriones hurrianae and Tatera indica; while notable infection has been reported in Nesokia indica as well. The purpose of this study is to model the distribution of these reservoirs to identify the risk areas of ZCL. A data bank was developed including all published data during the period of 1970-2015. Maximum entropy model was used to find the most appropriate ecological niches for each species. The areas under curve obtained were 0.961, 0.927, 0.922, 0.997 and 0.899, instead of 1, for training test in R. opimus, M. libycus, T. indica, M. hurrianae and N. indica, respectively. The environmental variable with the highest gain when used in isolation was slope for R. opimus and N. indica, annual mean temperature for M. libycus, and seasonal precipitation for T. indica and M. hurrianae. Summation of presence probabilities for three main species, i.e., R. opimus, M. libycus and T. indica revealed favorable ecological niches in wide areas of 16 provinces. This is the first study to predict the distribution of ZCL reservoir hosts in Iran. Climatology and topography variables had high contributions toward the prediction of potential distribution of the main reservoir species; therefore, as climate changes, the models should be updated periodically with novel data, and the results should be used in disease-monitoring programs.

  7. A Survey of Enterprise Architecture Analysis Using Multi Criteria Decision Making Models (MCDM)

    Science.gov (United States)

    Zia, Mehmooda Jabeen; Azam, Farooque; Allauddin, Maria

    System design becomes really important for software production due to continuous increase in size and complexity of software systems. It is a complex design activity to build architecture for the systems like large enterprises. Thus it is a critical issue to select the correct architecture in software engineering domain. Moreover, in enterprise architecture selection different goals and objectives must be taken into consideration as it is a multi-criteria decision making problem. Generally this field of enterprise architecture analysis has progressed from the application of linear weighting, through integer programming and linear programming to multi-criteria decision making (MCDM) models. In this paper we survey two multi-criteria decision making models (AHP, ANP) to determine that to what extent they have been used in making powerful decisions in complex enterprise architecture analysis. We have found that by using ANP model, decision makers of an enterprise can make more precise and suitable decisions in selection of enterprise architecture styles.

  8. Modeling cognitive and emotional processes: a novel neural network architecture.

    Science.gov (United States)

    Khashman, Adnan

    2010-12-01

    In our continuous attempts to model natural intelligence and emotions in machine learning, many research works emerge with different methods that are often driven by engineering concerns and have the common goal of modeling human perception in machines. This paper aims to go further in that direction by investigating the integration of emotion at the structural level of cognitive systems using the novel emotional DuoNeural Network (DuoNN). This network has hidden layer DuoNeurons, where each has two embedded neurons: a dorsal neuron and a ventral neuron for cognitive and emotional data processing, respectively. When input visual stimuli are presented to the DuoNN, the dorsal cognitive neurons process local features while the ventral emotional neurons process the entire pattern. We present the computational model and the learning algorithm of the DuoNN, the input information-cognitive and emotional-parallel streaming method, and a comparison between the DuoNN and a recently developed emotional neural network. Experimental results show that the DuoNN architecture, configuration, and the additional emotional information processing, yield higher recognition rates and faster learning and decision making.

  9. E-Governance and Service Oriented Computing Architecture Model

    Science.gov (United States)

    Tejasvee, Sanjay; Sarangdevot, S. S.

    2010-11-01

    E-Governance is the effective application of information communication and technology (ICT) in the government processes to accomplish safe and reliable information lifecycle management. Lifecycle of the information involves various processes as capturing, preserving, manipulating and delivering information. E-Governance is meant to transform of governance in better manner to the citizens which is transparent, reliable, participatory, and accountable in point of view. The purpose of this paper is to attempt e-governance model, focus on the Service Oriented Computing Architecture (SOCA) that includes combination of information and services provided by the government, innovation, find out the way of optimal service delivery to citizens and implementation in transparent and liable practice. This paper also try to enhance focus on the E-government Service Manager as a essential or key factors service oriented and computing model that provides a dynamically extensible structural design in which all area or branch can bring in innovative services. The heart of this paper examine is an intangible model that enables E-government communication for trade and business, citizen and government and autonomous bodies.

  10. A rock physics model for analysis of anisotropic parameters in a shale reservoir in Southwest China

    Science.gov (United States)

    Qian, Keran; Zhang, Feng; Chen, Shuangquan; Li, Xiangyang; Zhang, Hui

    2016-02-01

    A rock physics model is a very effective tool to describe the anisotropy and mechanical properties of rock from a seismology perspective. Compared to a conventional reservoir, modelling a shale reservoir requires us to face two main challenges in modelling: the existence of organic matter and strong anisotropy. We construct an anisotropic rock physics workflow for a typical shale reservoir in Southwest China, in which the organic matter is treated separately from other minerals by using a combination of anisotropic self-consistent approximation and the differential effective medium method. The standard deviation of the distribution function is used to model the degree of lamination of clay and kerogen. A double scan workflow is introduced to invert the probability of pore aspect ratio and lamination simultaneously, which can give us a better understanding of the shale formation. The anisotropic properties of target formation have been analysed based on the proposed model. Inverted Thomsen parameters, especially the sign of delta, are analysed in terms of the physical properties of rock physics modelling.

  11. Pi: A Parallel Architecture Interface for Multi-Model Execution

    Science.gov (United States)

    1990-07-01

    Directory Schemes for Cache Coherence. In The 15th Annual Interna- tional Symposium on Computer Architecture. IEEE Computer Society and ACM, June 1988. [3...Annual International Symposium on Computer Architecture. IEEE Computer Society and ACM, June 1986. [5] Arvind and Rishiyur S. Nikhil. A Dataflow...Overview, 1987. [9] Roberto Bisiani and Alessandro Forin. Multilanguage Parallel Programming of Heterogeneous Machines. IEEE Transactions on Computers

  12. Modeling Open Software Architectures of Robot Controllers: A Brief Survey of Modeling Methods and Developing Methods

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Openness is one of the features of modern robot controllers. Although many modeling technologies have been discussed to model and develop open robot controllers, the focus is always on modeling methodologies. Meanwhile, the relations between the former and the latter are usually ignored. According to the general software architecture of open robot controllers, this paper discusses modeling and developing methods. And the relationships between the typical ones are also analyzed.

  13. Modelling the impacts of climate change on hydrology and water quality in a mediterranean limno-reservoir

    DEFF Research Database (Denmark)

    Molina-Navarro, Euginio; Trolle, Dennis; Martinez-Pérez, Silvia

    Assessment Tool (SWAT) model developed for a small Mediterranean catchment to quantify the potential effects of various climate change scenarios on catchment hydrology as well as the trophic state of a new kind of waterbody, a limno-reservoir (Pareja Limno-reservoir), created for environmental...

  14. A fully-coupled geomechanics and flow model for hydraulic fracturing and reservoir engineering applications

    Energy Technology Data Exchange (ETDEWEB)

    Charoenwongsa, S.; Kazemi, H.; Miskimins, J.; Fakcharoenphol [Colorado School of Mines, Golden, CO (United States)

    2010-07-01

    A fully coupled geomechanics flow model was used to assess how the changes in pore pressure and temperature influence rock stresses in tight gas reservoirs. The finite difference method was used to develop simulations for phases, components, and thermal stresses. A wave component was used to model the propagation of the strain displacement front as well as changes in stress with time. Fluid and heat flow volumes were modelled separately from rock formation properties. The influence of hydraulic fracturing on stress distributions surrounding the fracture was investigated as well as the effect of filter cake and filtrate. Results of the study showed that significant changes in shear stresses near hydraulic fractures occur as a result of hydraulic fracture face displacement perpendicular to the fracture face. While temperature effects also caused changes in stress distributions, changes in pore pressure did not significantly impact shear stresses as the filtrate did not travel very far into the reservoir. 17 refs., 17 figs.

  15. On the effects of adaptive reservoir operating rules in hydrological physically-based models

    Science.gov (United States)

    Giudici, Federico; Anghileri, Daniela; Castelletti, Andrea; Burlando, Paolo

    2017-04-01

    Recent years have seen a significant increase of the human influence on the natural systems both at the global and local scale. Accurately modeling the human component and its interaction with the natural environment is key to characterize the real system dynamics and anticipate future potential changes to the hydrological regimes. Modern distributed, physically-based hydrological models are able to describe hydrological processes with high level of detail and high spatiotemporal resolution. Yet, they lack in sophistication for the behavior component and human decisions are usually described by very simplistic rules, which might underperform in reproducing the catchment dynamics. In the case of water reservoir operators, these simplistic rules usually consist of target-level rule curves, which represent the average historical level trajectory. Whilst these rules can reasonably reproduce the average seasonal water volume shifts due to the reservoirs' operation, they cannot properly represent peculiar conditions, which influence the actual reservoirs' operation, e.g., variations in energy price or water demand, dry or wet meteorological conditions. Moreover, target-level rule curves are not suitable to explore the water system response to climate and socio economic changing contexts, because they assume a business-as-usual operation. In this work, we quantitatively assess how the inclusion of adaptive reservoirs' operating rules into physically-based hydrological models contribute to the proper representation of the hydrological regime at the catchment scale. In particular, we contrast target-level rule curves and detailed optimization-based behavioral models. We, first, perform the comparison on past observational records, showing that target-level rule curves underperform in representing the hydrological regime over multiple time scales (e.g., weekly, seasonal, inter-annual). Then, we compare how future hydrological changes are affected by the two modeling

  16. Chance-Constrained Model for Real-Time Reservoir Operation Using Drought Duration Curve

    Science.gov (United States)

    Takeuchi, Kuniyoshi

    1986-04-01

    The seasonal drought duration curve (SDDC) ƒβ (m|τ) is defined as a deterministic equivalent of an average streamflow over an m-day period starting from date τ with probability of failure being β. This curve provides an estimate of a sum of inflows over m days starting from date τ in a T ( = 1/β)-year drought. The reservoir system considered is a single-purpose reservoir already in service. The demand pattern is predetermined, and the percentage of deficit in meeting the demand (supply cut) is left to operators' judgement. A chance-constrained model was developed for such a system. The model determined the percentage of supply cut on date τ in such the way that the probability of exhaustion of reservoir storage Sτ+m at the beginning of date τ+m was maintained less than a given constant βm for all 1 ≤ m ≤ M, i.e., Prob {Sτ+m ≤ 0} ≤ βm, m = 1, 2, …, M, where M is the number of days in the future to be considered to make a current decision on date τ, and βm are a given set of allowable exhaustion probability selected from an indifferent preference curve between reservoir exhaustion probability β and anticipated time to its occurrence, m. The reservoir operation rule thus developed was named as DDC rule curves and demonstrated satisfactorily operational through a simulation study of the Fukuoka drought case during 1978-1979.

  17. Exploration drilling and reservoir model of the Platanares geothermal system, Honduras, Central America

    Science.gov (United States)

    Goff, F.; Goff, S.J.; Kelkar, S.; Shevenell, L.; Truesdell, A.H.; Musgrave, J.; Rufenacht, H.; Flores, W.

    1991-01-01

    Results of drilling, logging, and testing of three exploration core holes, combined with results of geologic and hydrogeochemical investigations, have been used to present a reservoir model of the Platanares geothermal system, Honduras. Geothermal fluids circulate at depths ??? 1.5 km in a region of active tectonism devoid of Quaternary volcanism. Large, artesian water entries of 160 to 165??C geothermal fluid in two core holes at 625 to 644 m and 460 to 635 m depth have maximum flow rates of roughly 355 and 560 l/min, respectively, which are equivalent to power outputs of about 3.1 and 5.1 MW(thermal). Dilute, alkali-chloride reservoir fluids (TDS ??? 1200 mg/kg) are produced from fractured Miocene andesite and Cretaceous to Eocene redbeds that are hydrothermally altered. Fracture permeabillity in producing horizons is locally greater than 1500 and bulk porosity is ??? 6%. A simple, fracture-dominated, volume-impedance model assuming turbulent flow indicates that the calculated reservoir storage capacity of each flowing hole is approximately 9.7 ?? 106 l/(kg cm-2), Tritium data indicate a mean residence time of 450 yr for water in the reservoir. Multiplying the natural fluid discharge rate by the mean residence time gives an estimated water volume of the Platanares system of ??? 0.78 km3. Downward continuation of a 139??C/km "conductive" gradient at a depth of 400 m in a third core hole implies that the depth to a 225??C source reservoir (predicted from chemical geothermometers) is at least 1.5 km. Uranium-thorium disequilibrium ages on calcite veins at the surface and in the core holes indicate that the present Platanares hydrothermal system has been active for the last 0.25 m.y. ?? 1991.

  18. Numerical modeling of oil displacement by water from fractured-pore reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Kats, R.M.; Avakyan, E.A.

    1984-01-01

    The process of oil displacement by water in a fractured-pore bed in a two-dimensional statement is mathematically modelled directly. The initial is a two-dimensional filtering model of two immiscible liquids with regard for the capillary forces and gravity in the porous medium. Adaptation of this model for the case of fractured-pore collector is done by reducing the filtering and geometric parameters of this model according to the parameters of the reservoir model represented by a continuum with double porosity, and making the appropriate changes in the algorithm and the computation program.

  19. Simulation-optimization model of reservoir operation based on target storage curves

    Institute of Scientific and Technical Information of China (English)

    Hong-bin FANG; Tie-song HU; Xiang ZENG; Feng-yan WU

    2014-01-01

    This paper proposes a new storage allocation rule based on target storage curves. Joint operating rules are also proposed to solve the operation problems of a multi-reservoir system with joint demands and water transfer-supply projects. The joint operating rules include a water diversion rule to determine the amount of diverted water in a period, a hedging rule based on an aggregated reservoir to determine the total release from the system, and a storage allocation rule to specify the release from each reservoir. A simulation-optimization model was established to optimize the key points of the water diversion curves, the hedging rule curves, and the target storage curves using the improved particle swarm optimization (IPSO) algorithm. The multi-reservoir water supply system located in Liaoning Province, China, including a water transfer-supply project, was employed as a case study to verify the effectiveness of the proposed join operating rules and target storage curves. The results indicate that the proposed operating rules are suitable for the complex system. The storage allocation rule based on target storage curves shows an improved performance with regard to system storage distribution.

  20. Computer Modeling of the Displacement Behavior of Carbon Dioxide in Undersaturated Oil Reservoirs

    Directory of Open Access Journals (Sweden)

    Ju Binshan

    2015-11-01

    Full Text Available The injection of CO2 into oil reservoirs is performed not only to improve oil recovery but also to store CO2 captured from fuel combustion. The objective of this work is to develop a numerical simulator to predict quantitatively supercritical CO2 flooding behaviors for Enhanced Oil Recovery (EOR. A non-isothermal compositional flow mathematical model is developed. The phase transition diagram is designed according to the Minimum Miscibility Pressure (MMP and CO2 maximum solubility in oil phase. The convection and diffusion of CO2 mixtures in multiphase fluids in reservoirs, mass transfer between CO2 and crude and phase partitioning are considered. The governing equations are discretized by applying a fully implicit finite difference technique. Newton-Raphson iterative technique was used to solve the nonlinear equation systems and a simulator was developed. The performances of CO2 immiscible and miscible flooding in oil reservoirs are predicted by the new simulator. The distribution of pressure and temperature, phase saturations, mole fraction of each component in each phase, formation damage caused by asphaltene precipitation and the improved oil recovery are predicted by the simulator. Experimental data validate the developed simulator by comparison with simulation results. The applications of the simulator in prediction of CO2 flooding in oil reservoirs indicate that the simulator is robust for predicting CO2 flooding performance.

  1. Faults simulations for three-dimensional reservoir-geomechanical models with the extended finite element method

    Science.gov (United States)

    Prévost, Jean H.; Sukumar, N.

    2016-01-01

    Faults are geological entities with thicknesses several orders of magnitude smaller than the grid blocks typically used to discretize reservoir and/or over-under-burden geological formations. Introducing faults in a complex reservoir and/or geomechanical mesh therefore poses significant meshing difficulties. In this paper, we consider the strong-coupling of solid displacement and fluid pressure in a three-dimensional poro-mechanical (reservoir-geomechanical) model. We introduce faults in the mesh without meshing them explicitly, by using the extended finite element method (X-FEM) in which the nodes whose basis function support intersects the fault are enriched within the framework of partition of unity. For the geomechanics, the fault is treated as an internal displacement discontinuity that allows slipping to occur using a Mohr-Coulomb type criterion. For the reservoir, the fault is either an internal fluid flow conduit that allows fluid flow in the fault as well as to enter/leave the fault or is a barrier to flow (sealing fault). For internal fluid flow conduits, the continuous fluid pressure approximation admits a discontinuity in its normal derivative across the fault, whereas for an impermeable fault, the pressure approximation is discontinuous across the fault. Equal-order displacement and pressure approximations are used. Two- and three-dimensional benchmark computations are presented to verify the accuracy of the approach, and simulations are presented that reveal the influence of the rate of loading on the activation of faults.

  2. Proactive modeling of water quality impacts of extreme precipitation events in a drinking water reservoir.

    Science.gov (United States)

    Jeznach, Lillian C; Hagemann, Mark; Park, Mi-Hyun; Tobiason, John E

    2017-10-01

    Extreme precipitation events are of concern to managers of drinking water sources because these occurrences can affect both water supply quantity and quality. However, little is known about how these low probability events impact organic matter and nutrient loads to surface water sources and how these loads may impact raw water quality. This study describes a method for evaluating the sensitivity of a water body of interest from watershed input simulations under extreme precipitation events. An example application of the method is illustrated using the Wachusett Reservoir, an oligo-mesotrophic surface water reservoir in central Massachusetts and a major drinking water supply to metropolitan Boston. Extreme precipitation event simulations during the spring and summer resulted in total organic carbon, UV-254 (a surrogate measurement for reactive organic matter), and total algae concentrations at the drinking water intake that exceeded recorded maximums. Nutrient concentrations after storm events were less likely to exceed recorded historical maximums. For this particular reservoir, increasing inter-reservoir transfers of water with lower organic matter content after a large precipitation event has been shown in practice and in model simulations to decrease organic matter levels at the drinking water intake, therefore decreasing treatment associated oxidant demand, energy for UV disinfection, and the potential for formation of disinfection byproducts. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Nonlinear Model Predictive Control for Oil Reservoirs Management

    DEFF Research Database (Denmark)

    Capolei, Andrea

    . With this objective function we link the optimization problem in production optimization to the Markowitz portfolio optimization problem in finance or to the the robust design problem in topology optimization. In this study we focus on open-loop configuration, i.e. without measurement feedback. We demonstrate......, the research community is working on improving current feedback model-based optimal control technologies. The topic of this thesis is production optimization for water flooding in the secondary phase of oil recovery. We developed numerical methods for nonlinear model predictive control (NMPC) of an oil field....... Further, we studied the use of robust control strategies in both open-loop, i.e. without measurement feedback, and closed-loop, i.e. with measurement feedback, configurations. This thesis has three main original contributions: The first contribution in this thesis is to improve the computationally...

  4. Reconstruction of rocks petrophysical properties as input data for reservoir modeling

    Science.gov (United States)

    Cantucci, B.; Montegrossi, G.; Lucci, F.; Quattrocchi, F.

    2016-11-01

    The worldwide increasing energy demand triggered studies focused on defining the underground energy potential even in areas previously discharged or neglected. Nowadays, geological gas storage (CO2 and/or CH4) and geothermal energy are considered strategic for low-carbon energy development. A widespread and safe application of these technologies needs an accurate characterization of the underground, in terms of geology, hydrogeology, geochemistry, and geomechanics. However, during prefeasibility study-stage, the limited number of available direct measurements of reservoirs, and the high costs of reopening closed deep wells must be taken into account. The aim of this work is to overcome these limits, proposing a new methodology to reconstruct vertical profiles, from surface to reservoir base, of: (i) thermal capacity, (ii) thermal conductivity, (iii) porosity, and (iv) permeability, through integration of well-log information, petrographic observations on inland outcropping samples, and flow and heat transport modeling. As case study to test our procedure we selected a deep structure, located in the medium Tyrrhenian Sea (Italy). Obtained results are consistent with measured data, confirming the validity of the proposed model. Notwithstanding intrinsic limitations due to manual calibration of the model with measured data, this methodology represents an useful tool for reservoir and geochemical modelers that need to define petrophysical input data for underground modeling before the well reopening.

  5. Full field reservoir modeling of shale assets using advanced data-driven analytics

    Directory of Open Access Journals (Sweden)

    Soodabeh Esmaili

    2016-01-01

    Full Text Available Hydrocarbon production from shale has attracted much attention in the recent years. When applied to this prolific and hydrocarbon rich resource plays, our understanding of the complexities of the flow mechanism (sorption process and flow behavior in complex fracture systems - induced or natural leaves much to be desired. In this paper, we present and discuss a novel approach to modeling, history matching of hydrocarbon production from a Marcellus shale asset in southwestern Pennsylvania using advanced data mining, pattern recognition and machine learning technologies. In this new approach instead of imposing our understanding of the flow mechanism, the impact of multi-stage hydraulic fractures, and the production process on the reservoir model, we allow the production history, well log, completion and hydraulic fracturing data to guide our model and determine its behavior. The uniqueness of this technology is that it incorporates the so-called “hard data” directly into the reservoir model, so that the model can be used to optimize the hydraulic fracture process. The “hard data” refers to field measurements during the hydraulic fracturing process such as fluid and proppant type and amount, injection pressure and rate as well as proppant concentration. This novel approach contrasts with the current industry focus on the use of “soft data” (non-measured, interpretive data such as frac length, width, height and conductivity in the reservoir models. The study focuses on a Marcellus shale asset that includes 135 wells with multiple pads, different landing targets, well length and reservoir properties. The full field history matching process was successfully completed using this data driven approach thus capturing the production behavior with acceptable accuracy for individual wells and for the entire asset.

  6. Full field reservoir modeling of shale assets using advanced data-driven analytics

    Institute of Scientific and Technical Information of China (English)

    Soodabeh Esmaili; Shahab D. Mohaghegh

    2016-01-01

    Hydrocarbon production from shale has attracted much attention in the recent years. When applied to this prolific and hydrocarbon rich resource plays, our understanding of the complexities of the flow mechanism (sorption process and flow behavior in complex fracture systems-induced or natural) leaves much to be desired. In this paper, we present and discuss a novel approach to modeling, history matching of hydrocarbon production from a Marcellus shale asset in southwestern Pennsylvania using advanced data mining, pattern recognition and machine learning technologies. In this new approach instead of imposing our understanding of the flow mechanism, the impact of multi-stage hydraulic fractures, and the production process on the reservoir model, we allow the production history, well log, completion and hydraulic fracturing data to guide our model and determine its behavior. The uniqueness of this tech-nology is that it incorporates the so-called “hard data” directly into the reservoir model, so that the model can be used to optimize the hydraulic fracture process. The “hard data” refers to field measure-ments during the hydraulic fracturing process such as fluid and proppant type and amount, injection pressure and rate as well as proppant concentration. This novel approach contrasts with the current industry focus on the use of “soft data” (non-measured, interpretive data such as frac length, width, height and conductivity) in the reservoir models. The study focuses on a Marcellus shale asset that in-cludes 135 wells with multiple pads, different landing targets, well length and reservoir properties. The full field history matching process was successfully completed using this data driven approach thus capturing the production behavior with acceptable accuracy for individual wells and for the entire asset.

  7. Study of hierarchical federation architecture using multi-resolution modeling

    Institute of Scientific and Technical Information of China (English)

    HAO Yan-ling; SHEN Dong-hui; QIAN Hua-ming; DENG Ming-hui

    2004-01-01

    This paper aims at finding a solution to the problem aroused in complex system simulation, where a specific functional federation is coupled with other simulation systems. In other words, the communication information within the system may be received by other federates that participated in this united simulation. For the purpose of ensuring simulation system unitary character, a hierarchical federation architecture (HFA) is taken. Also considering the real situation, where federates in a complicated simulation system can be made simpler to an extent, a multi-resolution modeling (MRM) method is imported to implement the design of hierarchical federation. By utilizing the multiple resolution entity (MRE) modeling approach, MRE for federates are designed out. When different level training simulation is required, the appropriate MRE at corresponding layers can be called. The design method realizes the reuse feature of the simulation system and reduces simulation complexity and improves the validity of system Simulation Cost (SC). Taking submarine voyage training simulator (SVTS) for instance, a HFA for submarine is constructed inthis paper, which approves the feasibility of studied approach.

  8. Green IT engineering concepts, models, complex systems architectures

    CERN Document Server

    Kondratenko, Yuriy; Kacprzyk, Janusz

    2017-01-01

    This volume provides a comprehensive state of the art overview of a series of advanced trends and concepts that have recently been proposed in the area of green information technologies engineering as well as of design and development methodologies for models and complex systems architectures and their intelligent components. The contributions included in the volume have their roots in the authors’ presentations, and vivid discussions that have followed the presentations, at a series of workshop and seminars held within the international TEMPUS-project GreenCo project in United Kingdom, Italy, Portugal, Sweden and the Ukraine, during 2013-2015 and at the 1st - 5th Workshops on Green and Safe Computing (GreenSCom) held in Russia, Slovakia and the Ukraine. The book presents a systematic exposition of research on principles, models, components and complex systems and a description of industry- and society-oriented aspects of the green IT engineering. A chapter-oriented structure has been adopted for this book ...

  9. Modelling production system architectures in the early phases of product development

    DEFF Research Database (Denmark)

    Guðlaugsson, Tómas Vignir; Martin Ravn, Poul; Mortensen, Niels Henrik;

    2016-01-01

    on – leading to an improved basis for prioritizing activities in the project. Requirements for the contents of the framework are presented, and literature on production and system models is reviewed. The production system architecture modelling framework is founded on methods and approaches in literature......This article suggests a framework for modelling a production system architecture in the early phases of product development.The challenge in these phases is that the products to be produced are not completely defined and yet decisions need to be made early in the process on what investments...... and adjusted to fit the modelling requirements of a production system architecture at an early phase of development. The production system architecture models capture and describe the structure, capabilities and expansions of the production system architecture underdevelopment. The production system...

  10. An implicit control-volume finite element method for well-reservoir modelling

    Science.gov (United States)

    Pavlidis, Dimitrios; Salinas, Pablo; Xie, Zhihua; Pain, Christopher; Matar, Omar

    2016-11-01

    Here a novel implicit approach (embodied within the IC-Ferst) is presented for modelling wells with potentially a large number of laterals within reservoirs. IC-Ferst is a conservative and consistent, control-volume finite element method (CV-FEM) model and fully unstructured/geology conforming meshes with anisotropic mesh adaptivity. As far as the wells are concerned, a multi-phase/multi-well approach, where well systems are represented as phases, is taken here. Phase volume fraction conservation equations are solved for in both the reservoir and the wells, in addition, the field within wells is also solved for. A second novel aspect of the work is the combination of modelling and resolving of the motherbore and laterals. In this case wells do not have to be explicitly discretised in space. This combination proves to be accurate (in many situations) as well as computationally efficient. The method is applied to a number of multi-phase reservoir problems in order to gain an insight into the effectiveness, in terms of production rate, of perforated laterals. Model results are compared with semi-analytical solutions for simple cases and industry-standard codes for more complicated cases. EPSRC UK Programme Grant MEMPHIS (EP/K003976/1).

  11. A coupled three-dimensional hydrodynamic model for predicting hypolimnetic oxygenation and epilimnetic mixing in a shallow eutrophic reservoir

    Science.gov (United States)

    Chen, Shengyang; Lei, Chengwang; Carey, Cayelan C.; Gantzer, Paul A.; Little, John C.

    2017-01-01

    Artificial mixing and hypolimnetic oxygenation are two common methods for improving water quality in reservoirs. To examine the effects of their operation on the thermal structure of the water column, we used a three-dimensional hydrodynamic model coupled with a newly developed water-jet model and an existing linear bubble-plume model in conjunction with whole-reservoir in situ mixing experiments in a drinking-water reservoir. This reservoir has a side-stream supersaturation (SSS) hypolimnetic oxygenation system and a bubble-plume epilimnetic mixing (EM) system installed to reduce hypolimnetic hypoxia and algal blooms. The results show that the SSS successfully adds dissolved oxygen to the hypolimnion without destratifying the reservoir, whereas the EM, located at the lower metalimnetic boundary, deepens this boundary and partially mixes the metalimnion and epilimnion. The newly developed water-jet model coupled with the hydrodynamic model can successfully predict the variation of the thermal structure in the reservoir. The extent to which the SSS and EM systems affect the thermal structure of the reservoir is also quantified by further application of the coupled hydrodynamic model.

  12. System Identification Based Proxy Model of a Reservoir under Water Injection

    Directory of Open Access Journals (Sweden)

    Berihun M. Negash

    2017-01-01

    Full Text Available Simulation of numerical reservoir models with thousands and millions of grid blocks may consume a significant amount of time and effort, even when high performance processors are used. In cases where the simulation runs are required for sensitivity analysis, dynamic control, and optimization, the act needs to be repeated several times by continuously changing parameters. This makes it even more time-consuming. Currently, proxy models that are based on response surface are being used to lessen the time required for running simulations during sensitivity analysis and optimization. Proxy models are lighter mathematical models that run faster and perform in place of heavier models that require large computations. Nevertheless, to acquire data for modeling and validation and develop the proxy model itself, hundreds of simulation runs are required. In this paper, a system identification based proxy model that requires only a single simulation run and a properly designed excitation signal was proposed and evaluated using a benchmark case study. The results show that, with proper design of excitation signal and proper selection of model structure, system identification based proxy models are found to be practical and efficient alternatives for mimicking the performance of numerical reservoir models. The resulting proxy models have potential applications for dynamic well control and optimization.

  13. Modeling energy flow in a large Neotropical reservoir: a tool do evaluate fishing and stability

    Directory of Open Access Journals (Sweden)

    Ronaldo Angelini

    Full Text Available Recently, there is an increasing perception that the ecosystem approach gives important insights to support fisheries stock assessment and management. This paper aims to quantify energy flows in the Itaipu Reservoir (Brazil and to simulate increase of the fishing effort of some species, using Ecopath with Ecosim software, which could allow inferences on stability. Therefore, two steady-state Itaipu models were built (1983-87 and 1988-92. Results showed that: a there are no differences between models, and results on aging trends do not vary over time indicating that fishery does not alter the ecosystem as a whole; b results of fisheries simulations are approximate to mono-specific stock assessment for the same species and periods; c many authors believe that tropical ecosystems are environments where biotic and abiotic oscillations are annual and sometimes unexpected, but the results found for the Itaipu Reservoir indicate that stability was met after 16 years.

  14. Sediment Deposition Pattern and Flow Conditions in the Three Gorges Reservoir: A Physical Model Study

    Institute of Scientific and Technical Information of China (English)

    王兴奎; 邵学军; 李丹勋

    2003-01-01

    Sedimentation in the Three Gorges Reservoir will greatly affect future project functions, such as power generation and navigation, after 50 years of operation. This paper presents results of a physical model study, which indicate that the capacity of both the discharge tunnel and the power plant outlet could be impaired by sediment deposition in front of the dam after 50 years, affecting both the hydropower head and navigation. A flow training scheme based on the third-stage cofferdam for the dam construction is proposed to regulate the flow pattern and control deposition in the near-dam region of the reservoir. This flow training scenario can effectively reduce deposition in the physical model.

  15. Research on Model and Related Parameters of Supercritical CO2 Injection into Depleted Reservoir

    Science.gov (United States)

    Ma, Pinghua; He, Jun

    2017-07-01

    On the basis of the research on CO2 geological storage and enhanced oil recovery(EOR) technology, a random porosity distribution model which conforms to logarithmic normal distribution was adopted in order to describe the heterogeneous characteristics of pore structure. On this basis, the two-phase flow model of CO2-formation water was established to describe the displacement process. Through the simulation of CO2 injection into depleted reservoir, it confirmed that injection point pressure was associated with the temperature and depth of the formation except heterogeneity. But the saturation distribution was greatly influenced by formation heterogeneity and depth. Thus, the space utilization of the injection layer reduced gradually with the depth increasing. The related research is important for CO2 storage, migration and evolution in depleted reservoir.

  16. Dynamic information architecture system (DIAS) : multiple model simulation management.

    Energy Technology Data Exchange (ETDEWEB)

    Simunich, K. L.; Sydelko, P.; Dolph, J.; Christiansen, J.

    2002-05-13

    Dynamic Information Architecture System (DIAS) is a flexible, extensible, object-based framework for developing and maintaining complex multidisciplinary simulations of a wide variety of application contexts. The modeling domain of a specific DIAS-based simulation is determined by (1) software Entity (domain-specific) objects that represent the real-world entities that comprise the problem space (atmosphere, watershed, human), and (2) simulation models and other data processing applications that express the dynamic behaviors of the domain entities. In DIAS, models communicate only with Entity objects, never with each other. Each Entity object has a number of Parameter and Aspect (of behavior) objects associated with it. The Parameter objects contain the state properties of the Entity object. The Aspect objects represent the behaviors of the Entity object and how it interacts with other objects. DIAS extends the ''Object'' paradigm by abstraction of the object's dynamic behaviors, separating the ''WHAT'' from the ''HOW.'' DIAS object class definitions contain an abstract description of the various aspects of the object's behavior (the WHAT), but no implementation details (the HOW). Separate DIAS models/applications carry the implementation of object behaviors (the HOW). Any model deemed appropriate, including existing legacy-type models written in other languages, can drive entity object behavior. The DIAS design promotes plug-and-play of alternative models, with minimal recoding of existing applications. The DIAS Context Builder object builds a constructs or scenario for the simulation, based on developer specification and user inputs. Because DIAS is a discrete event simulation system, there is a Simulation Manager object with which all events are processed. Any class that registers to receive events must implement an event handler (method) to process the event during execution. Event handlers

  17. Visual product architecture modelling for structuring data in a PLM system

    DEFF Research Database (Denmark)

    Bruun, Hans Peter Lomholt; Mortensen, Niels Henrik

    2012-01-01

    The goal of this paper is to determine the role of a product architecture model to support communication and to form the basis for developing and maintaining information of product structures in a PLM system. This paper contains descriptions of a modelling tool to represent a product architecture....... Moreover, it is discussed how the sometimes intangible elements and phenomena within an architecture model can be visually modeled in order to form the basis for a data model in a PLM system. © 2012 International Federation for Information Processing....

  18. A vertically integrated eutrophication model and its application to a river-style reservoir - Fuchunjiang, China

    Institute of Scientific and Technical Information of China (English)

    WU Tingfeng; LUO Liancong; QIN Boqiang; CUI Guangbai; YU Zuoming; YAO Zhiming

    2009-01-01

    Based on a 2-D hydrodynamic model, a vertically integrated eutrophication model was developed. The physical sub-model can be used for calculation of water density at different depths and the water quality sub-model was for calculation of algal growth. Suspended solids were divided into two types of sediment which named cohesive and non-cohesive sediments and simulated using separate methods. The light extinction coefficient used in the underwater light regime sub-model was linearly related to the sum of sediment and phytoplankton biomass. Some components less important to the model were simplified to improve practicability and calculation efficiency. Using field data from Fuchunjiang Reservoir, we calculated the sensitivity of ecological parameters included in this model and validated the model. The results of sensitivity analysis showed that the parameters strongly influenced the phytoplankton biomass including phytoplankton maximum growth rate, respiration rate, non-predatory mortality rate, and settling rate, zooplankton maximum filtration rate, specific extinction coefficient for suspended solids and sediment oxygen demand rate. The model was calibrated by adjusting these parameters. Total chlorophyll a (chl-a) concentrations at different layers in the water column were reproduced very well by the model simulations. The simulated chl-a values were positively correlated to the measured values with Pearson correlation coefficient of 0.92. The mean difference between measured and simulated chl-a concentrations was 12% of the measured chl-a concentration. Measured and simulated DO concentrations were also positively correlated (r=0.74) and the mean difference was 4% of measured DO concentrations. The successful validation of model indicated that it would be very useful in water quality management and algal bloom prediction in Fuchunjiang Reservoir and a good tool for water quality regularation in other river-style reservoirs.

  19. An Executable Architecture Tool for the Modeling and Simulation of Operational Process Models

    Science.gov (United States)

    2015-03-16

    national coordination and iterative development. This paper includes a literature review, background information on process models and architecture...future work involves coordination with Subject Matter Experts ( SMEs ), and extracting data from experiments to assign more appropriate values. 3) Sub...development. This paper provided a brief description of other available tools, Fig. 10. Snapshot of Simulation Output Results for Example 3 background

  20. Modelling the International Climate Change Negotiations: A Non-Technical Outline of Model Architecture

    Energy Technology Data Exchange (ETDEWEB)

    Underdal, Arild

    1997-12-31

    This report discusses in non-technical terms the overall architecture of a model that will be designed to enable the user to (1) explore systematically the political feasibility of alternative policy options and (2) to determine the set of politically feasible solutions in the global climate change negotiations. 25 refs., 2 figs., 1 tab.

  1. Time-lapse seismic waveform modelling and attribute analysis using hydromechanical models for a deep reservoir undergoing depletion

    Science.gov (United States)

    He, Y.-X.; Angus, D. A.; Blanchard, T. D.; Wang, G.-L.; Yuan, S.-Y.; Garcia, A.

    2016-04-01

    Extraction of fluids from subsurface reservoirs induces changes in pore pressure, leading not only to geomechanical changes, but also perturbations in seismic velocities and hence observable seismic attributes. Time-lapse seismic analysis can be used to estimate changes in subsurface hydromechanical properties and thus act as a monitoring tool for geological reservoirs. The ability to observe and quantify changes in fluid, stress and strain using seismic techniques has important implications for monitoring risk not only for petroleum applications but also for geological storage of CO2 and nuclear waste scenarios. In this paper, we integrate hydromechanical simulation results with rock physics models and full-waveform seismic modelling to assess time-lapse seismic attribute resolution for dynamic reservoir characterization and hydromechanical model calibration. The time-lapse seismic simulations use a dynamic elastic reservoir model based on a North Sea deep reservoir undergoing large pressure changes. The time-lapse seismic traveltime shifts and time strains calculated from the modelled and processed synthetic data sets (i.e. pre-stack and post-stack data) are in a reasonable agreement with the true earth models, indicating the feasibility of using 1-D strain rock physics transform and time-lapse seismic processing methodology. Estimated vertical traveltime shifts for the overburden and the majority of the reservoir are within ±1 ms of the true earth model values, indicating that the time-lapse technique is sufficiently accurate for predicting overburden velocity changes and hence geomechanical effects. Characterization of deeper structure below the overburden becomes less accurate, where more advanced time-lapse seismic processing and migration is needed to handle the complex geometry and strong lateral induced velocity changes. Nevertheless, both migrated full-offset pre-stack and near-offset post-stack data image the general features of both the overburden and

  2. Optimized reservoir operation model of regional wind and hydro power integration. Case study: Zambezi Basin and South Africa

    OpenAIRE

    Gebretsadik, Yohannes; Fant, Chas; Strzepek, Kenneth

    2014-01-01

    The present study develops a reliability assessment method of wind resource using optimum reservoir target power operations that maximizes the firm generation of integrated wind and hydro power. A combined water resources model for a system of reservoirs that implements a priority based linear programing algorithm and a single node power grid system model is implemented on an hourly time step. This model was then accompanied by a genetic algorithm solver to determine optimum operation targets...

  3. A Novel Integrated Approach to Modelling of Depletion-Induced Change in Full Permeability Tensor of Naturally Fractured Reservoirs

    Directory of Open Access Journals (Sweden)

    Zahra Izadi

    2014-12-01

    Full Text Available More than half of all hydrocarbon reservoirs are Naturally Fractured Reservoirs (NFRs, in which production forecasting is a complicated function of fluid flow in a fracture-matrix system. Modelling of fluid flow in NFRs is challenging due to formation heterogeneity and anisotropy. Stress sensitivity and depletion effect on already-complex reservoir permeability add to the sophistication. Horizontal permeability anisotropy and stress sensitivity are often ignored or inaccurately taken into account when simulating fluid flow in NFRs. The aim of this paper is to present an integrated approach for evaluating the dynamic and true anisotropic nature of permeability in naturally fractured reservoirs. Among other features, this approach considers the effect of reservoir depletion on reservoir permeability tensor, allowing more realistic production forecasts. In this approach the NFR is discretized into grids for which an analytical model yields full permeability tensors. Then, fluid flow is modelled using the finite-element method to obtain pore-pressure distribution within the reservoir. Next, another analytical model evaluates the change in the aperture of individual fractures as a function of effective stress and rock mechanical properties. The permeability tensor of each grid is then updated based on the apertures obtained for the current time step. The integrated model proceeds according to the next prescribed time increments.

  4. Improving inflow forecasting into hydropower reservoirs through a complementary modelling framework

    Science.gov (United States)

    Gragne, A. S.; Sharma, A.; Mehrotra, R.; Alfredsen, K.

    2014-10-01

    Accuracy of reservoir inflow forecasts is instrumental for maximizing the value of water resources and benefits gained through hydropower generation. Improving hourly reservoir inflow forecasts over a 24 h lead-time is considered within the day-ahead (Elspot) market of the Nordic exchange market. We present here a new approach for issuing hourly reservoir inflow forecasts that aims to improve on existing forecasting models that are in place operationally, without needing to modify the pre-existing approach, but instead formulating an additive or complementary model that is independent and captures the structure the existing model may be missing. Besides improving forecast skills of operational models, the approach estimates the uncertainty in the complementary model structure and produces probabilistic inflow forecasts that entrain suitable information for reducing uncertainty in the decision-making processes in hydropower systems operation. The procedure presented comprises an error model added on top of an un-alterable constant parameter conceptual model, the models being demonstrated with reference to the 207 km2 Krinsvatn catchment in central Norway. The structure of the error model is established based on attributes of the residual time series from the conceptual model. Deterministic and probabilistic evaluations revealed an overall significant improvement in forecast accuracy for lead-times up to 17 h. Season based evaluations indicated that the improvement in inflow forecasts varies across seasons and inflow forecasts in autumn and spring are less successful with the 95% prediction interval bracketing less than 95% of the observations for lead-times beyond 17 h.

  5. Improving real-time inflow forecasting into hydropower reservoirs through a complementary modelling framework

    Science.gov (United States)

    Gragne, A. S.; Sharma, A.; Mehrotra, R.; Alfredsen, K.

    2015-08-01

    Accuracy of reservoir inflow forecasts is instrumental for maximizing the value of water resources and benefits gained through hydropower generation. Improving hourly reservoir inflow forecasts over a 24 h lead time is considered within the day-ahead (Elspot) market of the Nordic exchange market. A complementary modelling framework presents an approach for improving real-time forecasting without needing to modify the pre-existing forecasting model, but instead formulating an independent additive or complementary model that captures the structure the existing operational model may be missing. We present here the application of this principle for issuing improved hourly inflow forecasts into hydropower reservoirs over extended lead times, and the parameter estimation procedure reformulated to deal with bias, persistence and heteroscedasticity. The procedure presented comprises an error model added on top of an unalterable constant parameter conceptual model. This procedure is applied in the 207 km2 Krinsvatn catchment in central Norway. The structure of the error model is established based on attributes of the residual time series from the conceptual model. Besides improving forecast skills of operational models, the approach estimates the uncertainty in the complementary model structure and produces probabilistic inflow forecasts that entrain suitable information for reducing uncertainty in the decision-making processes in hydropower systems operation. Deterministic and probabilistic evaluations revealed an overall significant improvement in forecast accuracy for lead times up to 17 h. Evaluation of the percentage of observations bracketed in the forecasted 95 % confidence interval indicated that the degree of success in containing 95 % of the observations varies across seasons and hydrologic years.

  6. DEPENDABLE PRIVACY REQUIREMENTS BY AGILE MODELED LAYERED SECURITY ARCHITECTURES – WEB SERVICES CASE STUDY

    Directory of Open Access Journals (Sweden)

    M.Upendra Kumar

    2011-07-01

    Full Text Available Software Engineering covers the definition of processes, techniques and models suitable for its environment to guarantee quality of results. An important design artifact in any software development project is the Software Architecture. Software Architecture’s important part is the set of architectural design rules. A primary goal of the architecture is to capture the architecture design decisions. An important part of these design decisions consists of architectural design rules In an MDA (Model-Driven Architecture context, the design of the system architecture is captured in the models of the system. MDA is known to be layered approach for modeling the architectural design rules and uses design patterns to improve the quality of software system. And to include the security to the software system, security patterns are introduced that offer security at the architectural level. More over, agile software development methods are used to build secure systems. There are different methods defined in agile development as extreme programming (XP, scrum, feature driven development (FDD, test driven development (TDD, etc. Agile processing is includes the phases as agile analysis, agile design and agile testing. These phases are defined in layers of MDA to provide security at the modeling level which ensures that security at the system architecture stage will improve the requirements for that system. Agile modeled Layered Security Architectures increase the dependability of the architecture in terms of privacy requirements. We validate this with a case study of dependability of privacy of Web Services Security Architectures, which helps for secure service oriented security architecture. In this paper the major part is given to model architectural design rules using MDA so that architects and developers are responsible to automatic enforcement on the detailed design and easy to understand and use by both of them. This MDA approach is implemented in use of

  7. Trophic State and Toxic Cyanobacteria Density in Optimization Modeling of Multi-Reservoir Water Resource Systems

    Directory of Open Access Journals (Sweden)

    Andrea Sulis

    2014-04-01

    Full Text Available The definition of a synthetic index for classifying the quality of water bodies is a key aspect in integrated planning and management of water resource systems. In previous works [1,2], a water system optimization modeling approach that requires a single quality index for stored water in reservoirs has been applied to a complex multi-reservoir system. Considering the same modeling field, this paper presents an improved quality index estimated both on the basis of the overall trophic state of the water body and on the basis of the density values of the most potentially toxic Cyanobacteria. The implementation of the index into the optimization model makes it possible to reproduce the conditions limiting water use due to excessive nutrient enrichment in the water body and to the health hazard linked to toxic blooms. The analysis of an extended limnological database (1996–2012 in four reservoirs of the Flumendosa-Campidano system (Sardinia, Italy provides useful insights into the strengths and limitations of the proposed synthetic index.

  8. Water quality control in Third River Reservoir (Argentina using geographical information systems and linear regression models

    Directory of Open Access Journals (Sweden)

    Claudia Ledesma

    2013-08-01

    Full Text Available Water quality is traditionally monitored and evaluated based upon field data collected at limited locations. The storage capacity of reservoirs is reduced by deposits of suspended matter. The major factors affecting surface water quality are suspended sediments, chlorophyll and nutrients. Modeling and monitoring the biogeochemical status of reservoirs can be done through data from remote sensors. Since the improvement of sensors’ spatial and spectral resolutions, satellites have been used to monitor the interior areas of bodies of water. Water quality parameters, such as chlorophyll-a concentration and secchi disk depth, were found to have a high correlation with transformed spectral variables derived from bands 1, 2, 3 and 4 of LANDSAT 5TM satellite. We created models of estimated responses in regard to values of chlorophyll-a. To do so, we used population models of single and multiple linear regression, whose parameters are associated with the reflectance data of bands 2 and 4 of the sub-image of the satellite, as well as the data of chlorophyll-a obtained in 25 selected stations. According to the physico-chemical analyzes performed, the characteristics of the water in the reservoir of Rio Tercero, correspond to somewhat hard freshwater with calcium bicarbonate. The water was classified as usable as a source of plant treatment, excellent for irrigation because of its low salinity and low residual sodium carbonate content, but unsuitable for animal consumption because of its low salt content.

  9. Architectural models of ambient-PRISMA in channel ambient calculus

    OpenAIRE

    Ali, Nour; Tuosto, Emilio

    2011-01-01

    peer-reviewed Ambient-PRISMA is an architectural approach for specifying aspect-oriented software architecture and generating code of distributed and mobile systems. Ambient-PRISMA lacks a precise semantics due to the fact that it is based only on a metamodel. In this paper, Ambient-PRISMA is mapped into a formal language called Channel Ambient Calculus, a process algebra for specifying mobile applications that provides channels and ambients as first-class citizens. We...

  10. Formal and Informal Modeling of Fault Tolerant Noc Architectures

    Directory of Open Access Journals (Sweden)

    Mostefa BELARBI

    2015-11-01

    Full Text Available The suggested new approach based on B-Event formal technics consists of suggesting aspects and constraints related to the reliability of NoC (Network-On-chip and the over-cost related to the solutions of tolerances on the faults: a design of NoC tolerating on the faults for SoC (System-on-Chip containing configurable technology FPGA (Field Programmable Gates Array, by extracting the properties of the NoC architecture. We illustrate our methodology by developing several refinements which produce QNoC (Quality of Service of Network on chip switch architecture from specification to test. We will show how B-event formalism can follow life cycle of NoC design and test: for example the code VHDL (VHSIC Hardware Description Language simulation established of certain kind of architecture can help us to optimize the architecture and produce new architecture; we can inject the new properties related to the new QNoC architecture into formal B-event specification. B-event is associated to Rodin tool environment. As case study, the last stage of refinement used a wireless network in order to generate complete test environment of the studied application.

  11. Modeling the Contribution of Enterprise Architecture Practice to the Achievement of Business Goals

    Science.gov (United States)

    van Steenbergen, Marlies; Brinkkemper, Sjaak

    Enterprise architecture is a young, but well-accepted discipline in information management. Establishing the effectiveness of an enterprise architecture practice, however, appears difficult. In this chapter we introduce an architecture effectiveness model (AEM) to express how enterprise architecture practices are meant to contribute to the business goals of an organization. We developed an AEM for three different organizations. These three instances show that the concept of the AEM is applicable in a variety of organizations. It also shows that the objectives of enterprise architecture are not to be restricted to financial goals. The AEM can be used by organizations to set coherent priorities for their architectural practices and to define KPIs for measuring the effectiveness of these practices.

  12. A dam-reservoir module for a semi-distributed hydrological model

    Science.gov (United States)

    de Lavenne, Alban; Thirel, Guillaume; Andréassian, Vazken; Perrin, Charles; Ramos, Maria-Helena

    2017-04-01

    Developing modeling tools that help to assess the spatial distribution of water resources is a key issue to achieve better solutions for the optimal management of water availability among users in a river basin. Streamflow dynamics depends on (i) the spatial variability of rainfall, (ii) the heterogeneity of catchment behavior and response, and (iii) local human regulations (e.g., reservoirs) that store and control surface water. These aspects can be successfully handled by distributed or semi-distributed hydrological models. In this study, we develop a dam-reservoir module within a semi-distributed rainfall-runoff model (de Lavenne et al. 2016). The model runs at the daily time step, and has five parameters for each sub-catchment as well as a streamflow velocity parameter for flow routing. Its structure is based on two stores, one for runoff production and one for routing. The calibration of the model is performed from upstream to downstream sub-catchments, which efficiently uses spatially-distributed streamflow measurements. In a previous study, Payan et al. (2008) described a strategy to implement a dam module within a lumped rainfall-runoff model. Here we propose to adapt this strategy to a semi-distributed hydrological modelling framework. In this way, the specific location of existing reservoirs inside a river basin is explicitly accounted for. Our goal is to develop a tool that can provide answers to the different issues involved in spatial water management in human-influenced contexts and at large modelling scales. The approach is tested for the Seine basin in France. Results are shown for model performance with and without the dam module. Also, a comparison with the lumped GR5J model highlights the improvements obtained in model performance by considering human influences more explicitly, and by facilitating parameter identifiability. This work opens up new perspectives for streamflow naturalization analyses and scenario-based spatial assessment of water

  13. Dynamic reservoir characterization using 4D multicomponent seismic data and rock physics modeling at Delhi Field, Louisiana

    Science.gov (United States)

    Carvajal Meneses, Carla C.

    Pore pressure and CO2 saturation changes are important to detect and quantify for maximizing oil recovery in Delhi Field. Delhi Field is a enhanced oil recovery (EOR) project with active monitoring by 4D multicomponent seismic technologies. Dynamic rock physics modeling integrates the rich dataset of core, well logs, petrographic thin sections and facies providing a link between reservoir and elastic properties. The dynamic modeling in this high porosity sandstone reservoir shows that P-wave velocity is more sensitive to CO2 saturation while S-wave velocity is more sensitive to pore pressure changes. I use PP and PS seismic data to jointly invert for Vp=Vs ratio and acoustic impedance. This technique has the advantage of adding more information to the non-unique inversion problem. Combining the inversion results from the monitor surveys of June 2010 and August 2011 provides acoustic impedance and Vp=Vs percentage differences. The time-lapse inverted response enables dynamic characterization of the reservoir by fitting the predicted dynamic models (calibrated at the wells). Dynamic reservoir characterization adds value in this stratigraphic complex reservoir. The results indicate that reservoir heterogeneities and pore pressure gradients control the CO2 flow within the Paluxy reservoir. Injectors 148-2 and 140-1 showed CO2 is moving downdip following a distributary channel induced by differential pressure from an updip injector or a barrier caused by a heterogeneity in the reservoir. CO2 anomalies located above the Paluxy injector 148-2 indicates that CO2 is moving from the Paluxy up into the Tuscaloosa Formation. My work demonstrates that reservoir monitoring is necessary for reservoir management at Delhi Field.

  14. Relaxation limit of a compressible gas-liquid model with well-reservoir interaction

    Science.gov (United States)

    Solem, Susanne; Evje, Steinar

    2017-02-01

    This paper deals with the relaxation limit of a two-phase compressible gas-liquid model which contains a pressure-dependent well-reservoir interaction term of the form q (P_r - P) where q>0 is the rate of the pressure-dependent influx/efflux of gas, P is the (unknown) wellbore pressure, and P_r is the (known) surrounding reservoir pressure. The model can be used to study gas-kick flow scenarios relevant for various wellbore operations. One extreme case is when the wellbore pressure P is largely dictated by the surrounding reservoir pressure P_r. Formally, this model is obtained by deriving the limiting system as the relaxation parameter q in the full model tends to infinity. The main purpose of this work is to understand to what extent this case can be represented by a well-defined mathematical model for a fixed global time T>0. Well-posedness of the full model has been obtained in Evje (SIAM J Math Anal 45(2):518-546, 2013). However, as the estimates for the full model are dependent on the relaxation parameter q, new estimates must be obtained for the equilibrium model to ensure existence of solutions. By means of appropriate a priori assumptions and some restrictions on the model parameters, necessary estimates (low order and higher order) are obtained. These estimates that depend on the global time T together with smallness assumptions on the initial data are then used to obtain existence of solutions in suitable Sobolev spaces.

  15. Climate modeling - a tool for the assessment of the paleodistribution of source and reservoir rocks

    Energy Technology Data Exchange (ETDEWEB)

    Roscher, M.; Schneider, J.W. [Technische Univ. Bergakademie Freiberg (Germany). Inst. fuer Geologie; Berner, U. [Bundesanstalt fuer Geowissenschaften und Rohstoffe, Hannover (Germany). Referat Organische Geochemie/Kohlenwasserstoff-Forschung

    2008-10-23

    In an on-going project of BGR and TU Bergakademie Freiberg, numeric paleo-climate modeling is used as a tool for the assessment of the paleo-distribution of organic rich deposits as well as of reservoir rocks. This modeling approach is based on new ideas concerning the formation of the Pangea supercontinent. The new plate tectonic concept is supported by paleo- magnetic data as it fits the 95% confidence interval of published data. Six Permocarboniferous time slices (340, 320, 300, 290, 270, 255 Ma) were chosen within a first paleo-climate modeling approach as they represent the most important changes of the Late Paleozoic climate development. The digital maps have a resolution of 2.8 x 2.8 (T42), suitable for high-resolution climate modeling, using the PLASIM model. CO{sub 2} concentrations of the paleo-atmosphere and paleo-insolation values have been estimated by published methods. For the purpose of validation, quantitative model output, had to be transformed into qualitative parameters in order to be able to compare digital data with qualitative data of geologic indicators. The model output of surface temperatures and precipitation was therefore converted into climate zones. The reconstructed occurrences of geological indicators like aeolian sands, evaporites, reefs, coals, oil source rocks, tillites, phosphorites and cherts were then compared to the computed paleo-climate zones. Examples of the Permian Pangea show a very good agreement between model results and geological indicators. From the modeling approach we are able to identify climatic processes which lead to the deposition of hydrocarbon source and reservoir rocks. The regional assessment of such atmospheric processes may be used for the identification of the paleo-distribution of organic rich deposits or rock types suitable to form hydrocarbon reservoirs. (orig.)

  16. Comparing Transformation Possibilities of Topological Functioning Model and BPMN in the Context of Model Driven Architecture

    Directory of Open Access Journals (Sweden)

    Solomencevs Artūrs

    2016-05-01

    Full Text Available The approach called “Topological Functioning Model for Software Engineering” (TFM4SE applies the Topological Functioning Model (TFM for modelling the business system in the context of Model Driven Architecture. TFM is a mathematically formal computation independent model (CIM. TFM4SE is compared to an approach that uses BPMN as a CIM. The comparison focuses on CIM modelling and on transformation to UML Sequence diagram on the platform independent (PIM level. The results show the advantages and drawbacks the formalism of TFM brings into the development.

  17. A trans-domain convergence trust model for network trust architecture

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This paper presents and analyses five existing trust models for the establishment of network trust architecture, based on that, a new public key infrastructure (PKI) interoperability trust mode with trans-domain convergence is proposed, moreover, its applications on the construction of interoperability models are compared with those of other five models, which shows that this new model maintains the independence and self-management of own system, namely, accords with practical PKI architecture operation.

  18. On model architecture for a children's speech recognition interactive dialog system

    OpenAIRE

    Kraleva, Radoslava; Kralev, Velin

    2016-01-01

    This report presents a general model of the architecture of information systems for the speech recognition of children. It presents a model of the speech data stream and how it works. The result of these studies and presented veins architectural model shows that research needs to be focused on acoustic-phonetic modeling in order to improve the quality of children's speech recognition and the sustainability of the systems to noise and changes in transmission environment. Another important aspe...

  19. FRACTURED RESERVOIR E&P IN ROCKY MOUNTAIN BASINS: A 3-D RTM MODELING APPROACH

    Energy Technology Data Exchange (ETDEWEB)

    P. Ortoleva; J. Comer; A. Park; D. Payne; W. Sibo; K. Tuncay

    2001-11-26

    Key natural gas reserves in Rocky Mountain and other U.S. basins are in reservoirs with economic producibility due to natural fractures. In this project, we evaluate a unique technology for predicting fractured reservoir location and characteristics ahead of drilling based on a 3-D basin/field simulator, Basin RTM. Recommendations are made for making Basin RTM a key element of a practical E&P strategy. A myriad of reaction, transport, and mechanical (RTM) processes underlie the creation, cementation and preservation of fractured reservoirs. These processes are often so strongly coupled that they cannot be understood individually. Furthermore, sedimentary nonuniformity, overall tectonics and basement heat flux histories make a basin a fundamentally 3-D object. Basin RTM is the only 3-D, comprehensive, fully coupled RTM basin simulator available for the exploration of fractured reservoirs. Results of Basin RTM simulations are presented, that demonstrate its capabilities and limitations. Furthermore, it is shown how Basin RTM is a basis for a revolutionary automated methodology for simultaneously using a range of remote and other basin datasets to locate reservoirs and to assess risk. Characteristics predicted by our model include reserves and composition, matrix and fracture permeability, reservoir rock strength, porosity, in situ stress and the statistics of fracture aperture, length and orientation. Our model integrates its input data (overall sedimentation, tectonic and basement heat flux histories) via the laws of physics and chemistry that describe the RTM processes to predict reservoir location and characteristics. Basin RTM uses 3-D, finite element solutions of the equations of rock mechanics, organic and inorganic diagenesis and multi-phase hydrology to make its predictions. As our model predicts reservoir characteristics, it can be used to optimize production approaches (e.g., assess the stability of horizontal wells or vulnerability of fractures to

  20. Integrating acoustic analysis in the architectural design process using parametric modelling

    DEFF Research Database (Denmark)

    Peters, Brady

    2011-01-01

    This paper discusses how parametric modeling techniques can be used to provide architectural designers with a better understanding of the acoustic performance of their designs and provide acoustic engineers with models that can be analyzed using computational acoustic analysis software. Architects...... provide a method by which architects and engineers can work together more efficiently and communicate better. This research is illustrated through the design of an architectural project, a new school in Copenhagen, Denmark by JJW Architects, where parametric modeling techniques have been used in different......, acoustic performance can inform the geometry and material logic of the design. In this way, the architectural design and the acoustic analysis model become linked....

  1. High-performance modeling of CO2 sequestration by coupling reservoir simulation and molecular dynamics

    KAUST Repository

    Bao, Kai

    2013-01-01

    The present work describes a parallel computational framework for CO2 sequestration simulation by coupling reservoir simulation and molecular dynamics (MD) on massively parallel HPC systems. In this framework, a parallel reservoir simulator, Reservoir Simulation Toolbox (RST), solves the flow and transport equations that describe the subsurface flow behavior, while the molecular dynamics simulations are performed to provide the required physical parameters. Numerous technologies from different fields are employed to make this novel coupled system work efficiently. One of the major applications of the framework is the modeling of large scale CO2 sequestration for long-term storage in the subsurface geological formations, such as depleted reservoirs and deep saline aquifers, which has been proposed as one of the most attractive and practical solutions to reduce the CO2 emission problem to address the global-warming threat. To effectively solve such problems, fine grids and accurate prediction of the properties of fluid mixtures are essential for accuracy. In this work, the CO2 sequestration is presented as our first example to couple the reservoir simulation and molecular dynamics, while the framework can be extended naturally to the full multiphase multicomponent compositional flow simulation to handle more complicated physical process in the future. Accuracy and scalability analysis are performed on an IBM BlueGene/P and on an IBM BlueGene/Q, the latest IBM supercomputer. Results show good accuracy of our MD simulations compared with published data, and good scalability are observed with the massively parallel HPC systems. The performance and capacity of the proposed framework are well demonstrated with several experiments with hundreds of millions to a billion cells. To our best knowledge, the work represents the first attempt to couple the reservoir simulation and molecular simulation for large scale modeling. Due to the complexity of the subsurface systems

  2. High-Performance Modeling of Carbon Dioxide Sequestration by Coupling Reservoir Simulation and Molecular Dynamics

    KAUST Repository

    Bao, Kai

    2015-10-26

    The present work describes a parallel computational framework for carbon dioxide (CO2) sequestration simulation by coupling reservoir simulation and molecular dynamics (MD) on massively parallel high-performance-computing (HPC) systems. In this framework, a parallel reservoir simulator, reservoir-simulation toolbox (RST), solves the flow and transport equations that describe the subsurface flow behavior, whereas the MD simulations are performed to provide the required physical parameters. Technologies from several different fields are used to make this novel coupled system work efficiently. One of the major applications of the framework is the modeling of large-scale CO2 sequestration for long-term storage in subsurface geological formations, such as depleted oil and gas reservoirs and deep saline aquifers, which has been proposed as one of the few attractive and practical solutions to reduce CO2 emissions and address the global-warming threat. Fine grids and accurate prediction of the properties of fluid mixtures under geological conditions are essential for accurate simulations. In this work, CO2 sequestration is presented as a first example for coupling reservoir simulation and MD, although the framework can be extended naturally to the full multiphase multicomponent compositional flow simulation to handle more complicated physical processes in the future. Accuracy and scalability analysis are performed on an IBM BlueGene/P and on an IBM BlueGene/Q, the latest IBM supercomputer. Results show good accuracy of our MD simulations compared with published data, and good scalability is observed with the massively parallel HPC systems. The performance and capacity of the proposed framework are well-demonstrated with several experiments with hundreds of millions to one billion cells. To the best of our knowledge, the present work represents the first attempt to couple reservoir simulation and molecular simulation for large-scale modeling. Because of the complexity of

  3. 油藏立体开发探讨%Discussions on tridimensional reservoir development models

    Institute of Scientific and Technical Information of China (English)

    任芳祥

    2012-01-01

    In order to realize the effective development of buried hill light oil reservoirs, mid-deep massive heavy oil reservoirs with interbeds, and ultra-deep massive heavy oil reservoirs in the Liaohe Oilfield, three tridimensional development models are established: superposition of horizontal wells in multi-intervals and multi-layers, steam assisted plane displacement (vertical -wells) with combination of vertical gravity drainage (horizontal wells), and steam assisted liquor drainage by two superposed horizontal wells and production by vertical wells. The development mechanisms for these three tridimensional development models have been studied by field test, physical simulation and numerical simulation. The tridimensional development mechanisms of buried hill light oil reservoirs are uniform compaction action, vertical gravity action and joint supply action. The tridimensional development mechanisms of mid-deep massive heavy oil reservoir with interbeds are gravity drainage and steam flooding, and the tridimensional development mechanisms of ultra-deep massive heavy oil reservoir are gravity water drainage, reduction of heat losses and enhancement of production injection ratio. The field tests in the light oil reservoir of the Xinggu buried hill, raid-deep massive heavy oil reservoir in Xing VI oil layer of Block Du 84 and ultra-deep massive heavy oil reservoir of Block Wa 59 in the Liaohe Oilfield showed that tridimensional development can significantly improve crude oil production, and realize efficient development of oilfield.%为有效开发辽河油田潜山稀油油藏.隔夹层发育的中深层块状稠油油藏及特深层块状稠油油藏,建立了多段多层水平井叠置、直井注汽平面驱替加水平井垂向重力泄油、叠置双水平井注汽排液加直井采油3种立体开发模型,采用现场测试、物理模拟、数值模拟等技术研究了3种立体开发方式的开发机理.潜山稀油油藏立体开发机理为分段均压作

  4. An architectural model of conscious and unconscious brain functions: Global Workspace Theory and IDA.

    Science.gov (United States)

    Baars, Bernard J; Franklin, Stan

    2007-11-01

    While neural net models have been developed to a high degree of sophistication, they have some drawbacks at a more integrative, "architectural" level of analysis. We describe a "hybrid" cognitive architecture that is implementable in neuronal nets, and which has uniform brainlike features, including activation-passing and highly distributed "codelets," implementable as small-scale neural nets. Empirically, this cognitive architecture accounts qualitatively for the data described by Baars' Global Workspace Theory (GWT), and Franklin's LIDA architecture, including state-of-the-art models of conscious contents in action-planning, Baddeley-style Working Memory, and working models of episodic and semantic longterm memory. These terms are defined both conceptually and empirically for the current theoretical domain. The resulting architecture meets four desirable goals for a unified theory of cognition: practical workability, autonomous agency, a plausible role for conscious cognition, and translatability into plausible neural terms. It also generates testable predictions, both empirical and computational.

  5. Selecting a High-Quality Central Model for Sharing Architectural Knowledge

    NARCIS (Netherlands)

    Liang, Peng; Jansen, Anton; Avgeriou, Paris; Zhu, H

    2008-01-01

    In the field of software architecture, there has been a paradigm shift front describing the outcome of architecting process to documenting Architectural Knowledge (AK), such as design decisions and rationale. To this end, a series of domain models have been proposed for defining the concepts and the

  6. Generic Architecture for Cloud Infrastructure as a Service (IaaS) Provisioning Model

    NARCIS (Netherlands)

    Demchenko, Y.; Ham, J. van der; Strijkers, R.J.; Ghijsen, M.; Ngo, C.; Cristea, M.

    2011-01-01

    This document provides information about the proposed architectural framework for Cloud Infrastructure as a Service (IaaS) provisioning model that includes the following components: the Composable Services Architecture (CSA) that intends to provide a conceptual and methodological framework for devel

  7. Modelling the impacts of climate change on hydrology and water quality in a mediterranean limno-reservoir

    DEFF Research Database (Denmark)

    Molina-Navarro, Euginio; Trolle, Dennis; Martinez-Pérez, Silvia

    Assessment Tool (SWAT) model developed for a small Mediterranean catchment to quantify the potential effects of various climate change scenarios on catchment hydrology as well as the trophic state of a new kind of waterbody, a limno-reservoir (Pareja Limno-reservoir), created for environmental...... in the Pareja Limno-reservoir and a switch from an oligo-mesotrophic to a mesotrophic state, which may threaten the maintenance of a favourable water quality. Our model framework may help water managers to assess and manage how climate change affects aquatic ecosystems....

  8. Equation of state density models for hydrocarbons in ultradeep reservoirs at extreme temperature and pressure conditions

    Science.gov (United States)

    Wu, Yue; Bamgbade, Babatunde A.; Burgess, Ward A.; Tapriyal, Deepak; Baled, Hseen O.; Enick, Robert M.; McHugh, Mark A.

    2013-10-01

    The necessity of exploring ultradeep reservoirs requires the accurate prediction of hydrocarbon density data at extreme temperatures and pressures. In this study, three equations of state (EoS) models, Peng-Robinson (PR), high-temperature high-pressure volume-translated PR (HTHP VT-PR), and perturbed-chain statistical associating fluid theory (PC-SAFT) EoS are used to predict the density data for hydrocarbons in ultradeep reservoirs at temperatures to 523 K and pressures to 275 MPa. The calculated values are compared with experimental data. The results show that the HTHP VT-PR EoS and PC-SAFT EoS always perform better than the regular PR EoS for all the investigated hydrocarbons.

  9. Accelerating 3D Visualization in Reservoir Modeling System with Programmable Hardware

    Directory of Open Access Journals (Sweden)

    Lin Liu

    2013-05-01

    Full Text Available This study presents a new method on 3D visualization in reservoir modeling system by using the computation power of modern programmable Graphics hardware (GPU. The proposed scheme is devised to achieve parallel processing of massive reservoir logging data. By taking advantage of the GPU's parallel processing capability, moreover, the performance of our scheme is discussed in comparison with that of the implementation entirely running on CPU. Experimental results clearly show that the proposed parallel processing can remarkably accelerate the data clustering task. Especially, although data-transferring from GPU to CPU is generally costly, acceleration by GPU is significant to save the total execution time of data-clustering and also significantly alleviates the computing load on CPU.

  10. Depositional models and reservoir properties of Miocene reefs, Visayan Islands, Philippines

    Energy Technology Data Exchange (ETDEWEB)

    Carozzi, A.V. [Illinois Univ., Urbana, IL (United States)

    1995-01-01

    Recent commercial discoveries offshore Palawan have propelled the Philippines into the list of oil- and gas-producing countries, and have focussed on the importance of Miocene reefs as reservoirs. This new situation has motivated the update of earlier depositional-diagenetic models for the Miocene reefs in the Visayan Islands, which is presented in this paper. These reefs consisted of an association of corals, red algae, bryozoans, and encrusting foraminifers, which formed wave-resistant, constructed, barrier-and-atoll systems along the edge of narrow shelves, with associated back-reef patch reefs and frontal pinnacle reefs. The latter also grew on structural and depositional highs and platforms among deeper water carbonate mudstones and shales. Reservoirs developed in all the various types of buildups by extensive burial dissolution, often preceded (with the exception of some pinnacle reefs) by subaerial exposure generating secondary porosity by vadose to phreatic undersaturated dissolution. (author)

  11. Modelling of Seismic and Resistivity Responses during the Injection of CO2 in Sandstone Reservoir

    Science.gov (United States)

    Omar, Muhamad Nizarul Idhafi Bin; Almanna Lubis, Luluan; Nur Arif Zanuri, Muhammad; Ghosh, Deva P.; Irawan, Sonny; Regassa Jufar, Shiferaw

    2016-07-01

    Enhanced oil recovery plays vital role in production phase in a producing oil field. Initially, in many cases hydrocarbon will naturally flow to the well as respect to the reservoir pressure. But over time, hydrocarbon flow to the well will decrease as the pressure decrease and require recovery method so called enhanced oil recovery (EOR) to recover the hydrocarbon flow. Generally, EOR works by injecting substances, such as carbon dioxide (CO2) to form a pressure difference to establish a constant productive flow of hydrocarbon to production well. Monitoring CO2 performance is crucial in ensuring the right trajectory and pressure differences are established to make sure the technique works in recovering hydrocarbon flow. In this paper, we work on computer simulation method in monitoring CO2 performance by seismic and resistivity model, enabling geoscientists and reservoir engineers to monitor production behaviour as respect to CO2 injection.

  12. Multi-objective game-theory models for conflict analysis in reservoir watershed management.

    Science.gov (United States)

    Lee, Chih-Sheng

    2012-05-01

    This study focuses on the development of a multi-objective game-theory model (MOGM) for balancing economic and environmental concerns in reservoir watershed management and for assistance in decision. Game theory is used as an alternative tool for analyzing strategic interaction between economic development (land use and development) and environmental protection (water-quality protection and eutrophication control). Geographic information system is used to concisely illustrate and calculate the areas of various land use types. The MOGM methodology is illustrated in a case study of multi-objective watershed management in the Tseng-Wen reservoir, Taiwan. The innovation and advantages of MOGM can be seen in the results, which balance economic and environmental concerns in watershed management and which can be interpreted easily by decision makers. For comparison, the decision-making process using conventional multi-objective method to produce many alternatives was found to be more difficult.

  13. Modeling of land use and reservoir effects on nonpoint source pollution in a highly agricultural basin

    Science.gov (United States)

    Wu, Yiping; Liu, Shu-Guang

    2012-01-01

    Nonpoint source (NPS) pollution is tightly linked to land use activities that determine the sources and magnitudes of pollutant loadings to stream water. The pollutant loads may also be alleviated within reservoirs because of the physical interception resulting from changed hydrological regimes and other biochemical processes. It is important but challenging to assess the NPS pollution processes with human effects due to the measurement limitations. The objective of this study is to evaluate the effects of human activities such as land uses and reservoir operation on the hydrological and NPS pollution processes in a highly agricultural area-the Iowa River Basin-using the Soil and Water Assessment Tool (SWAT). The evaluation of model performance at multiple sites reveals that SWAT can consistently simulate the daily streamflow, and monthly/annual sediment and nutrient loads (nitrate nitrogen and mineral phosphorus) in the basin. We also used the calibrated model to estimate the trap efficiencies of sediment (~78%) and nutrients (~30%) in the Coralville Reservoir within the basin. These non-negligible effects emphasize the significance of incorporating the sediment and nutrient removal mechanisms into watershed system studies. The spatial quantification of the critical NPS pollution loads can help identify hot-spot areas that are likely locations for the best management practices.

  14. Modeling of land use and reservoir effects on nonpoint source pollution in a highly agricultural basin.

    Science.gov (United States)

    Wu, Yiping; Liu, Shuguang

    2012-09-01

    Nonpoint source (NPS) pollution is tightly linked to land use activities that determine the sources and magnitudes of pollutant loadings to stream water. The pollutant loads may also be alleviated within reservoirs because of the physical interception resulting from changed hydrological regimes and other biochemical processes. It is important but challenging to assess the NPS pollution processes with human effects due to the measurement limitations. The objective of this study is to evaluate the effects of human activities such as land uses and reservoir operation on the hydrological and NPS pollution processes in a highly agricultural area-the Iowa River Basin-using the Soil and Water Assessment Tool (SWAT). The evaluation of model performance at multiple sites reveals that SWAT can consistently simulate the daily streamflow, and monthly/annual sediment and nutrient loads (nitrate nitrogen and mineral phosphorus) in the basin. We also used the calibrated model to estimate the trap efficiencies of sediment (∼78%) and nutrients (∼30%) in the Coralville Reservoir within the basin. These non-negligible effects emphasize the significance of incorporating the sediment and nutrient removal mechanisms into watershed system studies. The spatial quantification of the critical NPS pollution loads can help identify hot-spot areas that are likely locations for the best management practices.

  15. Discrete Fracture Network Modelling in a Naturally Fractured Carbonate Reservoir in the Jingbei Oilfield, China

    Directory of Open Access Journals (Sweden)

    Junling Fang

    2017-02-01

    Full Text Available This paper presents an integrated approach of discrete fracture network modelling for a naturally fractured buried-hill carbonate reservoir in the Jingbei Oilfield by using a 3D seismic survey, conventional well logs, and core data. The ant tracking attribute, extracted from 3D seismic data, is used to detect the faults and large-scale fractures. Fracture density and dip angle are evaluated by observing drilling cores of seven wells. The fracture density distribution in spatiality was predicted in four steps; firstly, the ant tracking attribute was extracted as a geophysical log; then an artificial neural network model was built by relating the fracture density with logs, e.g., acoustic, gamma ray, compensated neutron, density, and ant tracking; then 3D distribution models of acoustic, gamma ray, compensated neutron and density were generated by using a Gaussian random function simulation; and, finally, the fracture density distribution in 3D was predicted by using the generated artificial neural network model. Then, different methods were used to build the discrete fracture network model for different types of fractures of which large-scale fractures were modelled deterministically and small-scale fractures were modelled stochastically. The results show that the workflow presented in this study is effective for building discrete fracture network models for naturally fractured reservoirs.

  16. Reactive Transport Modeling and Geophysical Monitoring of Bioclogging at Reservoir Scale

    Science.gov (United States)

    Surasani, V.; Commer, M.; Ajo Franklin, J. B.; Li, L.; Hubbard, S. S.

    2012-12-01

    In Microbial-Enhanced-Hydrocarbon-Recovery (MEHR), preferential bioclogging targets the growth of the biofilms (def. immobilized biopolymers with active cells embodied in it) in highly permeable thief zones to enhance sweep efficiency in oil reservoirs. During MEHR, understanding and controlling bioclogging is hindered by the lack of advanced modeling and monitoring tools; these deficiencies contribute to suboptimal performance. Our focus in this study was on developing a systematic approach to understand and monitor bioclogging at the reservoir scale using a combination of reactive transport modeling and geophysical imaging tools (EM & seismic). In this study, we created a realistic reservoir model from a heterogeneous gas reservoir in the Southern Sacramento basin, California; the model well (Citizen Green #1) was characterized using sonic, electrical, nuclear, and NMR logs for hydrologic and geophysical properties. From the simplified 2D log data model, a strip of size 150m x75m with several high permeability streaks is identified for bioclogging simulation experiments. From the NMR log data it is observed that a good linear correlation exist between logarithmic permeability (0.55- 3.34 log (mD)) versus porosity (0.041-0.28). L. mesenteroides was chosen as the model bacteria. In the presence of sucrose, it enzymatically catalyzes the production of dextran, a useful bioclogging agent. Using microbial kinetics from our laboratory experiment and reservoir heterogeneity, a reactive transport model (RTM) is established for two kinds of bioclogging treatments based on whether microbes are present in situ or are supplied externally. In both cases, sucrose media (1.5 M) is injected at the rate of 1 liter/s for 20 days into the center of high permeable strip to stimulate microbes. Simulations show that the high dextran production was deep into the formation from the injection well. This phenomenon can be explained precisely with bacterial kinetics and injection rate. In

  17. Determination of crystal residence timescales in magma reservoirs by diffusion modeling of dendritic phosphorus zoning patterns in olivine

    Science.gov (United States)

    Chakraborty, S.; Potrafke, A.

    2016-12-01

    Deciphering the early stages of crystallization and the chronological evolution of phenocrysts in magma reservoirs is one of the main goals in volcanology. Established approaches that model the concentration evolution of fast diffusing elements like Fe/Mg carry limited information on timescales once the concentration gradients are homogenized. Elements that diffuse more slowly, such as P and Al, become useful in these cases. We present a novel modeling tool that combines high-resolution EMP mapping of slow diffusing phosphorus in olivine with 2D kinetic modeling of the diffusive relaxation of initial chemical zoning pattern of P as well as Fe/Mg. The modeling approach offers a new possibility for determining crystal residence times in magma reservoirs. P diffusion coefficients from the experimental determination of [1] and Fe/Mg diffusion coefficients from [2] were used. The method yields a time-bracket between the minimum time required to homogenize the zoning of fast-diffusing Fe/Mg and the maximum time period for which details of chemical zoning of slow-diffusing P may be retained. To illustrate the approach we have studied the compositional zoning patterns of 7 olivine crystals from Piton de la Fournaise volcano, La Réunion. All crystals show a narrow range of forsterite contents (=Fo82-84) with fully homogenized Fe/Mg distribution, whereas P-mapping reveals oscillatory to dendritic zoning patterns [3]. P concentrations scatter in the range of 0.4 wt-% to below detection limit. Revealed phosphorus zoning patterns were considered to display the initial crystal architecture, whereas Fe and Mg zoning has been wiped out due to faster diffusion. For La Réunion magmas at 1453 K, timescales between few days to weeks were determined to be the time brackets for growth and residence of the olivine crystals in the magmas. These short residence times combined with knowledge of very fast developing dendritic crystals that have recently been revealed worldwide [e.g. 3

  18. Modeling strategic competition in hydro-thermal electricity generation markets with cascaded reservoir-hydroelectric generation plants

    Science.gov (United States)

    Uluca, Basak

    This dissertation aims to achieve two goals. The first is to model the strategic interactions of firms that own cascaded reservoir-hydro plants in oligopolistic and mixed oligopolistic hydrothermal electricity generation markets. Although competition in thermal generation has been extensively modeled since the beginning of deregulation, the literature on competition in hydro generation is still limited; in particular, equilibrium models of oligopoly that study the competitive behavior of firms that own reservoir-hydro plants along the same river in hydrothermal electricity generation markets are still under development. In competitive markets, when the reservoirs are located along the same river, the water released from an upstream reservoir for electricity generation becomes input to the immediate downstream reservoir, which may be owned by a competitor, for current or future use. To capture the strategic interactions among firms with cascaded reservoir-hydro plants, the Upstream-Conjecture approach is proposed. Under the Upstream-Conjecture approach, a firm with an upstream reservoir-hydro plant assumes that firms with downstream reservoir-hydro plants will respond to changes in the upstream firm's water release by adjusting their water release by the same amount. The results of the Upstream Conjecture experiments indicate that firms that own upstream reservoirs in a cascade may have incentive to withhold or limit hydro generation, forcing a reduction in the utilization of the downstream hydro generation plants that are owned by competitors. Introducing competition to hydroelectricity generation markets is challenging and ownership allocation of the previously state-owned cascaded reservoir-hydro plants through privatization can have significant impact on the competitiveness of the generation market. The second goal of the dissertation is to extract empirical guidance about best policy choices for the ownership of the state-owned generation plants, including the

  19. Integrated, multidisciplinary reservoir characterization, modeling and engineering leading to enhanced oil recovery from the Midway-Sunset field, California

    Energy Technology Data Exchange (ETDEWEB)

    Schamel, S.; Forster, C.; Deo, M. (Univ. of Utah, Salt Lake City, UT (United States)) (and others)

    1996-01-01

    The Pru Fee property is developed in a heavy oil, Class III (slope and basin clastic sand), reservoir of the Midway-Sunset field, San Joaquin Basin, California. Wells on the property were shut-in with an estimated 85% of the original oil remaining in place because the reservoir failed to respond to conventional cyclic steaming. Producibility problems are attributed to the close proximity of the property to the margin of the field. Specific problems include complex reservoir geometry, thinning pay, bottom water, and dipping beds. These problems are likely common at the margins of the Midway-Sunset and other Class III reservoirs. This project forms the first step in returning the property to production and explores strategies that might be applied elsewhere. Reservoir characterization, modeling, and engineering methods are integrated to design, simulate, and implement a pilot steam flood. A new drillhole provides good quality, core through the pay zone and a full suite of geophysical logs. Correlations between geological and petrophysical data are used to extrapolate reservoir conditions from older logs and yield a 3-dimensional petrophysical model. Numerical results illustrate how each producibility problem might influence production and provide a framework for designing the pilot steam flood. This first phase illustrates how a multidisciplinary team can use established technologies in developing the detailed petrophysical, geological, and numerical models needed to enhance oil recovery from marginal areas of Class III reservoirs.

  20. Integrated, multidisciplinary reservoir characterization, modeling and engineering leading to enhanced oil recovery from the Midway-Sunset field, California

    Energy Technology Data Exchange (ETDEWEB)

    Schamel, S.; Forster, C.; Deo, M. [Univ. of Utah, Salt Lake City, UT (United States)] [and others

    1996-12-31

    The Pru Fee property is developed in a heavy oil, Class III (slope and basin clastic sand), reservoir of the Midway-Sunset field, San Joaquin Basin, California. Wells on the property were shut-in with an estimated 85% of the original oil remaining in place because the reservoir failed to respond to conventional cyclic steaming. Producibility problems are attributed to the close proximity of the property to the margin of the field. Specific problems include complex reservoir geometry, thinning pay, bottom water, and dipping beds. These problems are likely common at the margins of the Midway-Sunset and other Class III reservoirs. This project forms the first step in returning the property to production and explores strategies that might be applied elsewhere. Reservoir characterization, modeling, and engineering methods are integrated to design, simulate, and implement a pilot steam flood. A new drillhole provides good quality, core through the pay zone and a full suite of geophysical logs. Correlations between geological and petrophysical data are used to extrapolate reservoir conditions from older logs and yield a 3-dimensional petrophysical model. Numerical results illustrate how each producibility problem might influence production and provide a framework for designing the pilot steam flood. This first phase illustrates how a multidisciplinary team can use established technologies in developing the detailed petrophysical, geological, and numerical models needed to enhance oil recovery from marginal areas of Class III reservoirs.

  1. Adaptive forward-inverse modeling of reservoir fluids away from wellbores

    Energy Technology Data Exchange (ETDEWEB)

    Ziagos, J P; Gelinas, R J; Doss, S K; Nelson, R G

    1999-07-30

    This Final Report contains the deliverables of the DeepLook Phase I project entitled, ''Adaptive Forward-Inverse Modeling of Reservoir Fluids Away from Wellbores''. The deliverables are: (i) a description of 2-D test problem results, analyses, and technical descriptions of the techniques used, (ii) a listing of program setup commands that construct and execute the codes for selected test problems (these commands are in mathematical terminology, which reinforces technical descriptions in the text), and (iii) an evaluation and recommendation regarding continuance of this project, including considerations of possible extensions to 3-D codes, additional technical scope, and budget for the out-years. The far-market objective in this project is to develop advanced technologies that can help locate and enhance the recovery of oil from heterogeneous rock formations. The specific technical objective in Phase I was to develop proof-of-concept of new forward and inverse (F-I) modeling techniques [Gelinas et al, 1998] that seek to enhance estimates (images) of formation permeability distributions and fluid motion away from wellbore volumes. This goes to the heart of improving industry's ability to jointly image reservoir permeability and flow predictions of trapped and recovered oil versus time. The estimation of formation permeability away from borehole measurements is an ''inverse'' problem. It is an inseparable part of modeling fluid flows throughout the reservoir in efforts to increase the efficiency of oil recovery at minimum cost. Classic issues of non-uniqueness, mathematical instability, noise effects, and inadequate numerical solution techniques have historically impeded progress in reservoir parameter estimations. Because information pertaining to fluid and rock properties is always sampled sparsely by wellbore measurements, a successful method for interpolating permeability and fluid data between the measurements must be

  2. A complex magma reservoir system for a large volume intra- to extra-caldera ignimbrite: Mineralogical and chemical architecture of the VEI8, Permian Ora ignimbrite (Italy)

    Science.gov (United States)

    Willcock, M. A. W.; Bargossi, G. M.; Weinberg, R. F.; Gasparotto, G.; Cas, R. A. F.; Giordano, G.; Marocchi, M.

    2015-11-01

    increases in SiO2, Y and Nb, with TiO2. Together, the changes enable subtle distinction of the Southern and Northern successions, indicating that the Northern deposits are more evolved. Furthermore, the data reveals discrimination within the Northern succession, with the northwestern extra-caldera fine-crystal-rich lithofacies, having a distinct texture, componentry and composition. The componentry variation, mineralogical and chemical ranges identified here are consistent with an eruption from a heterogeneous magma system. Our results suggest that the Ora magma was likely stored in multiple chambers within a genetically related magma reservoir network. The mineralogical and chemical architecture together with stratigraphic relationships, enable interpretation of eruption sequence. Caldera eruption is proposed to have commenced in the south and progressed to the north, forming the two pene-contemporaneous caldera depressions. Moreover, this data illustrates heterogeneity and local zonation from base-to-top of the main intra-caldera and extra-caldera successions. These variations together with crystal fragment size variations between ignimbrite lithofacies support the hypothesis of a multi-vent eruption process, incremental caldera in-filling by subtly compositionally different pyroclastic flow pulses, and a lower intensity eruption style (Willcock et al., 2013, 2014).

  3. Discrete fracture modeling of multiphase flow and hydrocarbon production in fractured shale or low permeability reservoirs

    Science.gov (United States)

    Hao, Y.; Settgast, R. R.; Fu, P.; Tompson, A. F. B.; Morris, J.; Ryerson, F. J.

    2016-12-01

    It has long been recognized that multiphase flow and transport in fractured porous media is very important for various subsurface applications. Hydrocarbon fluid flow and production from hydraulically fractured shale reservoirs is an important and complicated example of multiphase flow in fractured formations. The combination of horizontal drilling and hydraulic fracturing is able to create extensive fracture networks in low permeability shale rocks, leading to increased formation permeability and enhanced hydrocarbon production. However, unconventional wells experience a much faster production decline than conventional hydrocarbon recovery. Maintaining sustainable and economically viable shale gas/oil production requires additional wells and re-fracturing. Excessive fracturing fluid loss during hydraulic fracturing operations may also drive up operation costs and raise potential environmental concerns. Understanding and modeling processes that contribute to decreasing productivity and fracturing fluid loss represent a critical component for unconventional hydrocarbon recovery analysis. Towards this effort we develop a discrete fracture model (DFM) in GEOS (LLNL multi-physics computational code) to simulate multiphase flow and transfer in hydraulically fractured reservoirs. The DFM model is able to explicitly account for both individual fractures and their surrounding rocks, therefore allowing for an accurate prediction of impacts of fracture-matrix interactions on hydrocarbon production. We apply the DFM model to simulate three-phase (water, oil, and gas) flow behaviors in fractured shale rocks as a result of different hydraulic stimulation scenarios. Numerical results show that multiphase flow behaviors at the fracture-matrix interface play a major role in controlling both hydrocarbon production and fracturing fluid recovery rates. The DFM model developed in this study will be coupled with the existing hydro-fracture model to provide a fully integrated

  4. Semantic Web on Scope: A New Architectural Model for the Semantic Web

    Directory of Open Access Journals (Sweden)

    Haytham T. Al-Feel

    2008-01-01

    Full Text Available Problem Statement: Current web contains billions of documents and has many administrative problems and limitations; in addition to that the web content is still accessible only to humans. The solution to these problems is the Semantic Web. The Semantic Web is considered to be the extension for the current web. But there are problems facing the Semantic Web now, such as there is no clear architecture for it, there are four versions created by Tim Berners-Lee, but still up to now there is no agreement for one of these visions nor is there a clear picture for the relation between different layers inside this architecture and the associated technologies. The objectives of this study were to: (i Identify the weaknesses that existed in the previous architectures and (ii Reach a new architecture that corrects these weaknesses. Approach: This research uses the Qualitative Analysis Approach of Taylor and Renner, presents the four versions of the Semantic Web architecture, describing the function(s and status of each layer and associated technologies, evaluates them using Gerber evaluation method and determines other design principles needed to modify and adapt this architecture as a step toward an agreement for one Semantic Web architecture. Results: The design of a new model for the Semantic Web architecture depends on the idea of previous versions. Conclusion: As a step toward a unified architecture for the Semantic Web, our study of the Semantic Web architecture highlighted some weaknesses that existed in the previous architectures, modify, adapt and reach a new architecture that corrects these weaknesses.

  5. The ADAPT Tool: From AADL Architectural Models to Stochastic Petri Nets through Model Transformation

    CERN Document Server

    Rugina, Ana E; Kaaniche, Mohamed

    2008-01-01

    ADAPT is a tool that aims at easing the task of evaluating dependability measures in the context of modern model driven engineering processes based on AADL (Architecture Analysis and Design Language). Hence, its input is an AADL architectural model annotated with dependability-related information. Its output is a dependability evaluation model in the form of a Generalized Stochastic Petri Net (GSPN). The latter can be processed by existing dependability evaluation tools, to compute quantitative measures such as reliability, availability, etc.. ADAPT interfaces OSATE (the Open Source AADL Tool Environment) on the AADL side and SURF-2, on the dependability evaluation side. In addition, ADAPT provides the GSPN in XML/XMI format, which represents a gateway to other dependability evaluation tools, as the processing techniques for XML files allow it to be easily converted to a tool-specific GSPN.

  6. Electromagnetic Vibration Energy Harvesting Devices Architectures, Design, Modeling and Optimization

    CERN Document Server

    Spreemann, Dirk

    2012-01-01

    Electromagnetic vibration transducers are seen as an effective way of harvesting ambient energy for the supply of sensor monitoring systems. Different electromagnetic coupling architectures have been employed but no comprehensive comparison with respect to their output performance has been carried out up to now. Electromagnetic Vibration Energy Harvesting Devices introduces an optimization approach which is applied to determine optimal dimensions of the components (magnet, coil and back iron). Eight different commonly applied coupling architectures are investigated. The results show that correct dimensions are of great significance for maximizing the efficiency of the energy conversion. A comparison yields the architectures with the best output performance capability which should be preferably employed in applications. A prototype development is used to demonstrate how the optimization calculations can be integrated into the design–flow. Electromagnetic Vibration Energy Harvesting Devices targets the design...

  7. Modelling and visualising modular product architectures for mass customisation

    DEFF Research Database (Denmark)

    Mortensen, Niels Henrik; Pedersen, Rasmus; Kvist, Morten

    2008-01-01

    that the companies are striving for variety from a commercial- and simplicity from a manufacturing one. A conscious structuring of product architectures and/or the use of product platforms can help overcome this challenge. This paper presents a new method for the synthesis and visualisation of product architecture......Companies following a mass customisation strategy have to observe two prerequisites for success: they have to fulfil a wide variety of customer needs and demands, and to harvest the benefits from economies of scale within their organisation and supply chain. This leads to the situation...... concepts that puts emphasis on variety in markets while also treating the consequences in the manufacturing set-up. The work is based on the assumption that a graphical overview of a given solution space and relations between market demands, product architecture and manufacturing layout can support...

  8. Architecture, modeling, and analysis of a plasma impedance probe

    Science.gov (United States)

    Jayaram, Magathi

    Variations in ionospheric plasma density can cause large amplitude and phase changes in the radio waves passing through this region. Ionospheric weather can have detrimental effects on several communication systems, including radars, navigation systems such as the Global Positioning Sytem (GPS), and high-frequency communications. As a result, creating models of the ionospheric density is of paramount interest to scientists working in the field of satellite communication. Numerous empirical and theoretical models have been developed to study the upper atmosphere climatology and weather. Multiple measurements of plasma density over a region are of marked importance while creating these models. The lack of spatially distributed observations in the upper atmosphere is currently a major limitation in space weather research. A constellation of CubeSat platforms would be ideal to take such distributed measurements. The use of miniaturized instruments that can be accommodated on small satellites, such as CubeSats, would be key to achieving these science goals for space weather. The accepted instrumentation techniques for measuring the electron density are the Langmuir probes and the Plasma Impedance Probe (PIP). While Langmuir probes are able to provide higher resolution measurements of relative electron density, the Plasma Impedance Probes provide absolute electron density measurements irrespective of spacecraft charging. The central goal of this dissertation is to develop an integrated architecture for the PIP that will enable space weather research from CubeSat platforms. The proposed PIP chip integrates all of the major analog and mixed-signal components needed to perform swept-frequency impedance measurements. The design's primary innovation is the integration of matched Analog-to-Digital Converters (ADC) on a single chip for sampling the probes current and voltage signals. A Fast Fourier Transform (FFT) is performed by an off-chip Field-Programmable Gate Array (FPGA

  9. Fluid identification in tight sandstone reservoirs based on a new rock physics model

    Science.gov (United States)

    Sun, Jianmeng; Wei, Xiaohan; Chen, Xuelian

    2016-08-01

    To identify pore fluids, we establish a new rock physics model named the tight sandstone dual-porosity model based on the Voigt-Reuss-Hill model, approximation for the Xu-White model and Gassmann’s equation to predict elastic wave velocities. The modeling test shows that predicted sonic velocities derived from this rock physics model match well with measured ones from logging data. In this context, elastic moduli can be derived from the model. By numerical study and characteristic analyzation of different elastic properties, a qualitative fluid identification method based on Poisson’s ratio and the S-L dual-factor method based on synthetic moduli is proposed. Case studies of these two new methods show the applicability in distinguishing among different fluids and different layers in tight sandstone reservoirs.

  10. An integrated multi-level watershed-reservoir modeling system for examining hydrological and biogeochemical processes in small prairie watersheds.

    Science.gov (United States)

    Zhang, Hua; Huang, Guo H; Wang, Dunling; Zhang, Xiaodong; Li, Gongchen; An, Chunjiang; Cui, Zheng; Liao, Renfei; Nie, Xianghui

    2012-03-15

    Eutrophication of small prairie reservoirs presents a major challenge in water quality management and has led to a need for predictive water quality modeling. Studies are lacking in effectively integrating watershed models and reservoir models to explore nutrient dynamics and eutrophication pattern. A water quality model specific to small prairie water bodies is also desired in order to highlight key biogeochemical processes with an acceptable degree of parameterization. This study presents a Multi-level Watershed-Reservoir Modeling System (MWRMS) to simulate hydrological and biogeochemical processes in small prairie watersheds. It integrated a watershed model, a hydrodynamic model and an eutrophication model into a flexible modeling framework. It can comprehensively describe hydrological and biogeochemical processes across different spatial scales and effectively deal with the special drainage structure of small prairie watersheds. As a key component of MWRMS, a three-dimensional Willows Reservoir Eutrophication Model (WREM) is developed to addresses essential biogeochemical processes in prairie reservoirs and to generate 3D distributions of various water quality constituents; with a modest degree of parameterization, WREM is able to meet the limit of data availability that often confronts the modeling practices in small watersheds. MWRMS was applied to the Assiniboia Watershed in southern Saskatchewan, Canada. Extensive efforts of field work and lab analysis were undertaken to support model calibration and validation. MWRMS demonstrated its ability to reproduce the observed watershed water yield, reservoir water levels and temperatures, and concentrations of several water constituents. Results showed that the aquatic systems in the Assiniboia Watershed were nitrogen-limited and sediment flux played a crucial role in reservoir nutrient budget and dynamics. MWRMS can provide a broad context of decision support for water resources management and water quality

  11. Transit times and age distributions for reservoir models represented as nonlinear non-autonomuous systems

    Science.gov (United States)

    Müller, Markus; Meztler, Holger; Glatt, Anna; Sierra, Carlos

    2016-04-01

    We present theoretical methods to compute dynamic residence and transit time distributions for non-autonomous systems of pools governed by coupled nonlinear differential equations. Although transit time and age distributions have been used to describe reservoir models for a long time, a closer look to their assumptions reveals two major restrictions of generality in previous studies. First, the systems are assumed to be in equilibrium; and second, the equations under consideration are assumed to be linear. While both these assumptions greatly ease the computation and interpretation of transit time and age distributions they are not applicable to a wide range of problems. Moreover, the transfer of previous results learned from linear systems in steady state to the more complex nonlinear non-autonomous systems that do not even need to have equilibria, can be dangerously misleading. Fortunately the topic of time dependent age and transit time distributions has received some attention recently in hydrology, we aim to compute these distributions for systems of multiple reservoirs. We will discuss how storage selection functions can augment the information represented in an ODE system describing a system of reservoirs. We will present analytical and numerical algorithms and a Monte Carlo simulator to compute solutions for system transit time and age distributions for system-wide storage selection functions including the most simple, but important case of well mixed pools.

  12. Perturbation of geothermal reservoirs to fluids stimulation: numerical modelling and implication on induced seismicity.

    Science.gov (United States)

    Carlino, Stefano; De Natale, Giuseppe; Troise, Claudia; Giulia Di Giuseppe, Maria; Troiano, Antonio; Tramelli, Anna; Somma, Renato

    2016-04-01

    Fluid withdrawal and injection into the crust produces changes in the local stress field and pore pressure, involving different rock volumes depending on the injection flow rate and duration as well as on the medium permeability. This process is in different cases correlated to induced seismicity. In the case of geothermal power plants (e.g. fluids withdrawal and in several case withdrawal/reinjection) this correlation is vague and sometimes not well constrained by experimental data. We report here a set of simulations of withdrawal, injection and withdrawal-reinjection-cycles from/in the same geothermal reservoirs, by using the numerical code TOUGH2®. The simulations are applied to conceptual models of different geothermal reservoirs already published in previous works, whose main difference is in the permeability features and the depth of wells (Soultz, France; Campi Flegrei caldera and Ischia island, Italy). The numerical simulations are aimed to compare the time growth of perturbed volumes obtained with withdrawal reinjection cycle to those obtained during simple withdrawal or injection, using the same flow rates. Our results clearly point out that reinjection is much less critical than simple injection or withdrawal, because the perturbed volumes are remarkably small and, moreover, remain constant over the simulated time, of whatever duration. This fact reduces significantly the potential of the seismicity induced by pressure variation into the reservoirs.

  13. Reservoir observers: Model-free inference of unmeasured variables in chaotic systems.

    Science.gov (United States)

    Lu, Zhixin; Pathak, Jaideep; Hunt, Brian; Girvan, Michelle; Brockett, Roger; Ott, Edward

    2017-04-01

    Deducing the state of a dynamical system as a function of time from a limited number of concurrent system state measurements is an important problem of great practical utility. A scheme that accomplishes this is called an "observer." We consider the case in which a model of the system is unavailable or insufficiently accurate, but "training" time series data of the desired state variables are available for a short period of time, and a limited number of other system variables are continually measured. We propose a solution to this problem using networks of neuron-like units known as "reservoir computers." The measurements that are continually available are input to the network, which is trained with the limited-time data to output estimates of the desired state variables. We demonstrate our method, which we call a "reservoir observer," using the Rössler system, the Lorenz system, and the spatiotemporally chaotic Kuramoto-Sivashinsky equation. Subject to the condition of observability (i.e., whether it is in principle possible, by any means, to infer the desired unmeasured variables from the measured variables), we show that the reservoir observer can be a very effective and versatile tool for robustly reconstructing unmeasured dynamical system variables.

  14. An object oriented tool for modeling production data associated with reservoir simulation

    Energy Technology Data Exchange (ETDEWEB)

    Esau, R.; Wells, M.; Leiknes, J.

    1995-12-31

    An object oriented, cross platform, C++ application has been successfully developed for the manipulation of production data associated with reservoir engineering and reservoir simulation data. The application supports all the main categories of production data necessary for simulation including historical production and injection volumes, well deviation surveys and reservoir events such as completion data. Particular emphasis is placed on the rapid generation of accurate and representative simulation controls. Key features include time varying connection factors where parameters are calculated from perforation data specified in terms of measured depths and formations, a flexible timestep framework and the handling of deviated wells, partially penetrating wells and multiple completions within a single simulation cell. The paper will discuss how the development of this and associated applications has shown it is possible to efficiently build sophisticated, cross platform products if the appropriate tools, suppliers and methodology are used. Finally the paper will address how the application and corresponding application development environment helps address future uncertainties including the continuing hardware and software revolution, the move towards keywordless, {open_quotes}gridless{close_quotes} simulation on a geological model and the existence of multiple integration platforms.

  15. Description Model of Warehouse Architecture for Clinical Test at the Molecular Immunology Centre

    Directory of Open Access Journals (Sweden)

    Anthony Rafael Sotolongo León

    2012-05-01

    Full Text Available Accurate and detailed description of the architecture of computer systems is very important to achieve success in their development. As informatic solutions, data warehouses and software support decision-making in institutions that need to implement a detailed description of the architecture. Ralph Kimball proposes the aspects to be considered of the description and explains how it is done. There are specific models used to describe the architecture such as Kruchten 4 +1 views of meta-model or the Common Warehouse Metamodel (CWM however these models do not meet the need of the description that requires a data warehouse that integrates information from clinical trials of the Molecular Immunology Centre (CIM. In this paper we propose a model for describing the data warehouse architecture that fits the needs of the Molecular Immunology Center following the Kimball framework and using as UML 2.0 modeling language.

  16. Two-dimensional numerical modelling of dissolved and particulate pollutant transport in the Three Gorges Reservoir

    Science.gov (United States)

    Hu, W.; Wang, L.-J.; Chen, H.; Holbach, A.; Zheng, B.-H.; Norra, S.; Westrich, B.

    2012-04-01

    After impoundment of the Three Gorges Reservoir (TGR) in 2003, hydrological regimes of the Yangtze River, upstream and downstream of the Three Gorges Dam, have been changed enormously, leading to significant environmental, ecological and social impacts. Nutrients and pollutants from agriculture, industry and municipalities are of concern due to their impact on the aquatic environment and hence, transport behavior of sediment associated pollutants must be modeled and analyzed to establish a sustainable water reservoir management. As part of the Chinese-German Yangtze-Project [1], two-dimensional numerical model TELEMAC is applied to study the dissolved and particulate pollutant transport at different locations of concern in the TGR. In-situ measurement campaigns for morphology and water quality data using mobile measuring device (MINIBAT) are carried out to provide detailed information for the different water bodies at different time. Additional morphological data are taken from cross-section profiles in the literature, the digital elevation model (DEM) of Shuttle Radar Topography Mission (SRTM) from CGIAR. Daily and hourly water level and discharge, suspended sediment concentration and pollutant loads are obtained from the authorities and extracted from literature. The model describes the spatial-temporal flow field, transport and dispersion of sediment associated pollutants with emphasis on the dynamic interaction and mutual influence of the river Yangtze, its major tributaries and adjacent lagoon-like dead water bodies due to the 30 meter annual reservoir water level fluctuation. Since algae bloom, especially in the tributaries and side arms of the mainstream, is one of the major issues occurred after 2003, the results of the numerical modeling together with the statistical analysis of the MINIBAT measurements are used for the eutrophication status analysis. Acknowledgments The Yangtze-Project is funded by the Federal Ministry of Education and Research (BMBF

  17. Robotic Architectures

    Directory of Open Access Journals (Sweden)

    Mbali Mtshali

    2010-01-01

    Full Text Available In the development of mobile robotic systems, a robotic architecture plays a crucial role in interconnecting all the sub-systems and controlling the system. The design of robotic architectures for mobile autonomous robots is a challenging and complex task. With a number of existing architectures and tools to choose from, a review of the existing robotic architecture is essential. This paper surveys the different paradigms in robotic architectures. A classification of the existing robotic architectures and comparison of different proposals attributes and properties have been carried out. The paper also provides a view on the current state of designing robot architectures. It also proposes a conceptual model of a generalised robotic architecture for mobile autonomous robots.Defence Science Journal, 2010, 60(1, pp.15-22, DOI:http://dx.doi.org/10.14429/dsj.60.96

  18. Lithospheric Architecture, Heterogenities, Instabilities, Melting - insight form numerical modelling

    Science.gov (United States)

    Gorczyk, Weronika; Hobbs, Bruce; Ord, Alison; Gessner, Klaus; Gerya, Taras V.

    2010-05-01

    The seismological structure of the Earth's lithosphere is identified to be strongly heterogeneous in terms of thermal and rheological structures. Lithospheric discontinuities (sharp changes in the thermal and/or compositional structure) are thought to be long lived and are mostly correlated with major tectonic boundaries that commonly have been reactivated and which subsequently are the foci of magma intrusion and major mineralization. Resent studies have shown that mantle metasomatism is also controlled by such boundaries. This paper explores the control that lithospheric heterogeneity exerts on the thermal and chemical evolution during deformation subsequent to the development of the heterogeneity. We explore the behaviour of the rheological heterogeneous lithosphere in a compressional regime. The occurrence of such variations may be caused for instance by amalgamation of micro-continents such as is thought to be characteristic of the Yilgarn, Western Australia or South Africa. Theses micro-continents, due to diverse histories may be characterised by various thermal and rheological structures. The models are simplistic but illustrate the basic principles. The code used in this study is based on a conservative finite-difference, multi-grid, marker in cell method. Devolatilisation reactions and melting can affect the physical properties of rocks and are incorporated in a self-consistent manner. We use a petrological-thermomechanical modelling approach with all rock properties including mechanical properties calculated in the Lagrangian scheme for rock markers at every time step based on Gibbs free energy minimization as a function of the local pressure, temperature and rock composition. The results illustrate that initial structural complexity is necessary for and has a dramatic effect on fault and development, the growth of deep basins, core complex formation, melting and devolatilisation within the lithosphere. The horizontal and vertical variation in plastic

  19. Marine and fluvial facies modelling at petroleum reservoir scale; Modelisation des heterogeneites lithologiques a l'echelle du reservoir petrolier en milieu marin et fluviatile

    Energy Technology Data Exchange (ETDEWEB)

    Leflon, B.

    2005-10-15

    When modelling a petroleum reservoir, well data are very useful to model properties at a sub-seismic scale. Petrophysical properties like porosity or permeability are linked to the rock-type. Two methods based on well data have been developed to model facies. The first one is used to model marine carbonates deposits. The geometry of sedimentary layers is modelled through a special parameterization of the reservoir similar to Wheeler space. The time parameter is defined along the well paths thanks to correlations. The layer thickness is then extrapolated between wells. A given relationship between facies and bathymetry of sedimentation makes it possible to compute bathymetry along the well paths. Bathymetry is then extrapolated from wells and a reference map using the concept of accommodation. The model created this way is stratigraphically consistent. Facies simulation can then be constrained by the computed bathymetry. The second method describes a novel approach to fluvial reservoirs modelling. The core of the method lies in the association of a fairway with the channels to be simulated. Fairways are positioned so that all data are taken in account; they can be stochastic if unknown or explicitly entered if identified on seismic data. A potential field is defined within the fairway. Specifying a transfer function to map this potential field to thickness results in generating a channel inside the fairway. A residual component is stochastically simulated and added to the potential field creating realistic channel geometries. Conditioning to well data is obtained by applying the inverse transfer function at the data location to derive thickness values that will constrain the simulation of residuals. (author)

  20. Optimization of computer-based technology of creating large reservoir's Digital Elevation Models

    Science.gov (United States)

    Shikunova, Ekaterina; Pavlovsky, Andrew; Zemlyanov, Igor; Gorelits, Olga

    2010-05-01

    Using Digital Elevation Model of bottom and coastal zone for large-scale anthropogenic water reservoirs is very important for sustainable water management in actual conditions of Global Climate Change. DEM is unified monitoring base for different types of reservoirs in varied types of ecosystems in various environmental and economical conditions. It may be used for getting current morphometric characteristics, pollution and biodiversity analysis, monitoring bottom relief changing and making management decisions. In 2008-2009 State Oceanography Institute (SOI) carried out the DEMs for reservoirs of Volga river system. In 2008 in SOI was created DEM of Uglichsky reservoir, which is typical Russian reservoir. Methodology and computer-based technology were developed and evaluated. In 2009 in SOI were created DEMs of Gorkovsky, Volgogradsky and six reservoirs of Moscow region. Such result was achieved by optimization of DEM's creating process. Initially we used complex of GIS programs, which include GIS Map-2008 Panorama, ArcMap v.9.3.1, ArcView v.3.2a, Golden Surfer v.8, Global Mapper v.10. The input data are bathymetric survey data, large-scale maps (scale 1:10 000, 1:25 000) and remote sensing data of high resolution. Office analysis consists of several main milestones. 1. Vectorization of coastline and relief data from maps and remote sensing data using GIS Map-2008 by Panorama; ArcView v.3.2a. 2. Maps data elaboration with using bathymetric survey data. Because some maps are longstanding it is necessary to renew them. 3. Creating point's array including all data from maps, RSD and bathymetric survey. 4. Separation small calculation zones including four survey cross-sections. 5. Determine of anisotropy parameters, which depend on channel orientation. 6. Create shapes for clipping of correct grid zones. Each shape includes 2 cross-sections. Milestones 2-6 realize in ArcView v.3.2a. 7. Creating grid's array using Golden Surfer v.8 for each zone by interpolation method

  1. Enterprise Architecture-Based Risk and Security Modelling and Analysis

    NARCIS (Netherlands)

    Jonkers, Henk; Quartel, Dick A.C.; Kordy, Barbara; Ekstedt, Mathias; Seong Kim, Deng

    2016-01-01

    The growing complexity of organizations and the increasing number of sophisticated cyber attacks asks for a systematic and integral approach to Enterprise Risk and Security Management (ERSM). As enterprise architecture offers the necessary integral perspective, including the business and IT aspects

  2. Modeling & Analysis of Multicore Architectures for Embedded SIGINT Applications

    Science.gov (United States)

    2015-03-01

    Reducing Anisotropic Diffusion Implementation ............................................ 11 4. Results and Discussion... dissemination (PED). As one example, the utility of embedded processing architectures will be driven by energy efficiency as much as it will be by...Exploitation, Analysis and Production, Dissemination (PCPAD) technology development community [2]. Joint Publication 3-0 defines a permissive

  3. Model & scale as conceptual devices in architectural representation

    NARCIS (Netherlands)

    Stellingwerff, M.C.; Koorstra, P.A.

    2013-01-01

    This year we celebrate the tenth anniversary of our Computer Aided Manufacturing laboratory (CAMlab, http://www.camlab-bk.nl). From the start we provide laser cutting, CNC-milling and 3D-print facilities for the students and the researchers at the Faculty of Architecture in Delft. Over the past ten

  4. Evaluating the Effectiveness of Reference Models in Federating Enterprise Architectures

    Science.gov (United States)

    Wilson, Jeffery A.

    2012-01-01

    Agencies need to collaborate with each other to perform missions, improve mission performance, and find efficiencies. The ability of individual government agencies to collaborate with each other for mission and business success and efficiency is complicated by the different techniques used to describe their Enterprise Architectures (EAs).…

  5. Architectural modeling of pixel readout chips Velopix and Timepix3

    NARCIS (Netherlands)

    Poikela, T.; Plosila, J.; Westerlund, T.; Buytaert, J.; Campbell, M.; Llopart, X.; Plackett, R.; Wyllie, K.; van Beuzekom, M.; Gromov, V.; Kluit, R.; Zappon, F.; Zivkovic, V.; Brezina, C.; Desch, K.; Fang, X.; Kruth, A.

    2012-01-01

    We examine two digital architectures for front end pixel readout chips, Velopix and Timepix3. These readout chips are developed for tracking detectors in future high energy physics experiments. They must incorporate local intelligence in pixels for time-over-threshold measurement and sparse readout.

  6. Spectrum emission considerations for baseband-modeled CALLUM architectures

    DEFF Research Database (Denmark)

    Strandberg, Roland; Andreani, Pietro; Sundström, Lars

    2005-01-01

    . Simulation examples are presented on how three different CALLUM architectures behave for enhanced data rates for global system for mobile communications evolution and wide-band code-division multiple-access signals. In addition, we have considered the effects of loop time delay, which is the ultimate...

  7. Evaluating the Effectiveness of Reference Models in Federating Enterprise Architectures

    Science.gov (United States)

    Wilson, Jeffery A.

    2012-01-01

    Agencies need to collaborate with each other to perform missions, improve mission performance, and find efficiencies. The ability of individual government agencies to collaborate with each other for mission and business success and efficiency is complicated by the different techniques used to describe their Enterprise Architectures (EAs).…

  8. Hierarchical Acceleration of Multilevel Monte Carlo Methods for Computationally Expensive Simulations in Reservoir Modeling

    Science.gov (United States)

    Zhang, G.; Lu, D.; Webster, C.

    2014-12-01

    The rational management of oil and gas reservoir requires an understanding of its response to existing and planned schemes of exploitation and operation. Such understanding requires analyzing and quantifying the influence of the subsurface uncertainties on predictions of oil and gas production. As the subsurface properties are typically heterogeneous causing a large number of model parameters, the dimension independent Monte Carlo (MC) method is usually used for uncertainty quantification (UQ). Recently, multilevel Monte Carlo (MLMC) methods were proposed, as a variance reduction technique, in order to improve computational efficiency of MC methods in UQ. In this effort, we propose a new acceleration approach for MLMC method to further reduce the total computational cost by exploiting model hierarchies. Specifically, for each model simulation on a new added level of MLMC, we take advantage of the approximation of the model outputs constructed based on simulations on previous levels to provide better initial states of new simulations, which will help improve efficiency by, e.g. reducing the number of iterations in linear system solving or the number of needed time-steps. This is achieved by using mesh-free interpolation methods, such as Shepard interpolation and radial basis approximation. Our approach is applied to a highly heterogeneous reservoir model from the tenth SPE project. The results indicate that the accelerated MLMC can achieve the same accuracy as standard MLMC with a significantly reduced cost.

  9. Low resistivity oil(gas)-bearing reservoir conductive model --Dual water clay matrix conductive model in the north area of Tarim Basin, Xinjiang, China

    Institute of Scientific and Technical Information of China (English)

    潘和平; 王家映; 樊政军; 马勇; 柳建华; 李明强

    2001-01-01

    Shaly sands reservoir is one of the most distributive types of the oil