Science.gov

Sample records for advanced conceptual models

  1. Conceptualizing Telehealth in Nursing Practice: Advancing a Conceptual Model to Fill a Virtual Gap.

    PubMed

    Nagel, Daniel A; Penner, Jamie L

    2016-03-01

    Increasingly nurses use various telehealth technologies to deliver health care services; however, there has been a lag in research and generation of empirical knowledge to support nursing practice in this expanding field. One challenge to generating knowledge is a gap in development of a comprehensive conceptual model or theoretical framework to illustrate relationships of concepts and phenomena inherent to adoption of a broad range of telehealth technologies to holistic nursing practice. A review of the literature revealed eight published conceptual models, theoretical frameworks, or similar entities applicable to nursing practice. Many of these models focus exclusively on use of telephones and four were generated from qualitative studies, but none comprehensively reflect complexities of bridging nursing process and elements of nursing practice into use of telehealth. The purpose of this article is to present a review of existing conceptual models and frameworks, discuss predominant themes and features of these models, and present a comprehensive conceptual model for telehealth nursing practice synthesized from this literature for consideration and further development. This conceptual model illustrates characteristics of, and relationships between, dimensions of telehealth practice to guide research and knowledge development in provision of holistic person-centered care delivery to individuals by nurses through telehealth technologies. PMID:25858897

  2. Evaluation of the Conceptual Flow Model for a Deep Vadose Zone System Using Advanced Tensiometers

    SciTech Connect

    Deborah L. McElroy; Joel M. Hubbell

    2004-02-01

    Conceptual flow models provide a framework for predictive modeling of contaminant transport. This study tests the assumptions of steady state flow and a unit hydraulic gradient in a 177-m thick vadose zone beneath a mixed waste site, using a network of advanced tensiometers. The conceptual flow model at the waste site, located on the Idaho National Engineering Laboratory, describes moisture movement through a geologically complex site comprising basalt flows intercalated with sedimentary interbeds. The presence of sedimentary interbeds is expected to dampen and store much of the episodic recharge, resulting in near steady state conditions and unit gradient flow. Thirty advanced tensiometers in 18 wells provided field water potential data at depths ranging from 6.7 to 73.5 m below land surface, beneath and adjacent to the waste site. Measured water potentials from February 2000 through August 2002 ranged from near saturation (-30°cm of water) to about –400 cm of water. Above 17 m, the observed long-term drying trends were presumed to be a response to the cumulative effect of less-than-average annual precipitation for the last three years (2000 through 2002). Below 17°m, steady state conditions were observed at over half of the monitored locations. However, long-term drying and wetting trends were also observed at 9 of the 25 monitored locations below 17 m, in contrast to the steady state flow assumptions in the conceptual model. Long-term water potential changes ranged from ~20 to 200 cm of water. It is hypothesized that these drying trends are related to areas of focused infiltration, such as drainage ditches, and are a response to decreased runoff from three years of less than average precipitation. A unit gradient was indicated, by aligning dispersed monitoring locations along a presumed vertical profile.

  3. Conceptual IT model

    NASA Astrophysics Data System (ADS)

    Arnaoudova, Kristina; Stanchev, Peter

    2015-11-01

    The business processes are the key asset for every organization. The design of the business process models is the foremost concern and target among an organization's functions. Business processes and their proper management are intensely dependent on the performance of software applications and technology solutions. The paper is attempt for definition of new Conceptual model of IT service provider, it could be examined as IT focused Enterprise model, part of Enterprise Architecture (EA) school.

  4. Professional advancement of women in health care management: a conceptual model.

    PubMed

    Madsen, M K; Blide, L A

    1992-11-01

    Ragins and Sundstrom suggest three major conclusions based on power and gender differences within organizations. The first is that power develops or detracts as individuals progress along their career track. HIM professionals who accept the challenges that changing roles bring can also develop a new sensitivity to the value of power as a tool. They can use their negotiating skills to avoid being placed in work roles that result in a decrease in power. The second difference between men and women within organizations is that obstacles often impede women's career paths more than men's. Perceptions by women and men of a woman as homemaker and mother create serious conflicts when jobs are demanding and time intensive. Lastly, Ragins and Sundstrom suggest that career progression is influenced by both intrinsic factors (personal and professional) and extrinsic factors (organizational and interpersonal). The interaction between these factors is often driven by gender differences allowing men to progress and succeed, whereas women remain beneath the glass ceiling. HIM professionals, like other women health professionals, are graduating from advanced programs in health care and business administration at a greater rate than ever before in the history of this country. Not all these graduates will be able to acquire top-level administrative positions in the traditional health care institutions (e.g., hospitals). Therefore, if they wish to advance, they may have to move to nontraditional work settings. This is especially true for HIM professionals. The expanding computerized environment in traditional and nontraditional health care settings presents great potential for the development of new roles and responsibilities that have not been identified as male roles. HIM professionals and women in other health care professions who aspire to advance to upper administrative positions in traditional and nontraditional settings must be willing to take the risks inherent in assuming

  5. Professional advancement of women in health care management: a conceptual model.

    PubMed

    Madsen, M K; Blide, L A

    1992-11-01

    Ragins and Sundstrom suggest three major conclusions based on power and gender differences within organizations. The first is that power develops or detracts as individuals progress along their career track. HIM professionals who accept the challenges that changing roles bring can also develop a new sensitivity to the value of power as a tool. They can use their negotiating skills to avoid being placed in work roles that result in a decrease in power. The second difference between men and women within organizations is that obstacles often impede women's career paths more than men's. Perceptions by women and men of a woman as homemaker and mother create serious conflicts when jobs are demanding and time intensive. Lastly, Ragins and Sundstrom suggest that career progression is influenced by both intrinsic factors (personal and professional) and extrinsic factors (organizational and interpersonal). The interaction between these factors is often driven by gender differences allowing men to progress and succeed, whereas women remain beneath the glass ceiling. HIM professionals, like other women health professionals, are graduating from advanced programs in health care and business administration at a greater rate than ever before in the history of this country. Not all these graduates will be able to acquire top-level administrative positions in the traditional health care institutions (e.g., hospitals). Therefore, if they wish to advance, they may have to move to nontraditional work settings. This is especially true for HIM professionals. The expanding computerized environment in traditional and nontraditional health care settings presents great potential for the development of new roles and responsibilities that have not been identified as male roles. HIM professionals and women in other health care professions who aspire to advance to upper administrative positions in traditional and nontraditional settings must be willing to take the risks inherent in assuming

  6. Advancing a conceptual model of evidence-based practice implementation in public service sectors.

    PubMed

    Aarons, Gregory A; Hurlburt, Michael; Horwitz, Sarah McCue

    2011-01-01

    Implementation science is a quickly growing discipline. Lessons learned from business and medical settings are being applied but it is unclear how well they translate to settings with different historical origins and customs (e.g., public mental health, social service, alcohol/drug sectors). The purpose of this paper is to propose a multi-level, four phase model of the implementation process (i.e., Exploration, Adoption/Preparation, Implementation, Sustainment), derived from extant literature, and apply it to public sector services. We highlight features of the model likely to be particularly important in each phase, while considering the outer and inner contexts (i.e., levels) of public sector service systems. PMID:21197565

  7. Advanced wind turbine conceptual study

    NASA Astrophysics Data System (ADS)

    1995-07-01

    Objective was to develop improvements to an existing wind turbine that would make wind energy more competitive in 1993-1995, and to initiate studies of an advanced wind turbine configuration that would make wind energy competitive for bulk electricity generation by 1998-2000. Objective has been achieved.

  8. Ecosystem conceptual model- Mercury

    USGS Publications Warehouse

    Alpers, Charles N.; Eagles-Smith, Collin A.; Foe, Chris; Klasing, Susan; Marvin-DiPasquale, Mark C.; Slotton, Darell G.; Windham-Myers, Lisamarie

    2008-01-01

    mercury conceptual model and its four submodels (1. Methylation, 2. Bioaccumulation, 3. Human Health Effects, and 4. Wildlife Heath Effects) can be used to understand the general relationships among drivers and outcomes associated with mercury cycling in the Delta. Several linkages between important drivers and outcomes have been identified as important but highly uncertain (i.e. poorly understood). For example, there may be significant wildlife health effect of mercury on mammals and reptiles in the Delta, but there is currently very little or no information about it. The characteristics of such linkages are important when prioritizing and funding restoration projects and associated monitoring in the Delta and its tributaries.

  9. Advanced heat receiver conceptual design study

    NASA Technical Reports Server (NTRS)

    Kesseli, James; Saunders, Roger; Batchelder, Gary

    1988-01-01

    Solar Dynamic space power systems are candidate electrical power generating systems for future NASA missions. One of the key components of the solar dynamic power system is the solar receiver/thermal energy storage (TES) subsystem. Receiver development was conducted by NASA in the late 1960's and since then a very limited amount of work has been done in this area. Consequently the state of the art (SOA) receivers designed for the IOC space station are large and massive. The objective of the Advanced Heat Receiver Conceptual Design Study is to conceive and analyze advanced high temperature solar dynamic Brayton and Stirling receivers. The goal is to generate innovative receiver concepts that are half of the mass, smaller, and more efficient than the SOA. It is also necessary that these innovative receivers offer ease of manufacturing, less structural complexity and fewer thermal stress problems. Advanced Brayton and Stirling receiver storage units are proposed and analyzed in this study which can potentially meet these goals.

  10. Conceptual models of information processing

    NASA Technical Reports Server (NTRS)

    Stewart, L. J.

    1983-01-01

    The conceptual information processing issues are examined. Human information processing is defined as an active cognitive process that is analogous to a system. It is the flow and transformation of information within a human. The human is viewed as an active information seeker who is constantly receiving, processing, and acting upon the surrounding environmental stimuli. Human information processing models are conceptual representations of cognitive behaviors. Models of information processing are useful in representing the different theoretical positions and in attempting to define the limits and capabilities of human memory. It is concluded that an understanding of conceptual human information processing models and their applications to systems design leads to a better human factors approach.

  11. Model Breaking Points Conceptualized

    ERIC Educational Resources Information Center

    Vig, Rozy; Murray, Eileen; Star, Jon R.

    2014-01-01

    Current curriculum initiatives (e.g., National Governors Association Center for Best Practices and Council of Chief State School Officers 2010) advocate that models be used in the mathematics classroom. However, despite their apparent promise, there comes a point when models break, a point in the mathematical problem space where the model cannot,…

  12. Towards a Theory of Conceptual Modelling

    NASA Astrophysics Data System (ADS)

    Thalheim, Bernhard

    Conceptual modelling is a widely applied practice and has led to a large body of knowledge on constructs that might be used for modelling and on methods that might be useful for modelling. It is commonly accepted that database application development is based on conceptual modelling. It is however surprising that only very few publications have been published on a theory of conceptual modelling.

  13. Best of Both Worlds: A Conceptual Model for Integrating an Aging Specialization within an Advanced Generalist MSW Program

    ERIC Educational Resources Information Center

    Dakin, Emily K.; Quijano, Louise M.; Bishop, Pamela S.; Sheafor, Bradford W.

    2015-01-01

    Must a master's of social work (MSW) program's orientation be either advanced generalist or some form of specialist? Or is there the possibility of a hybrid curriculum that provides enough breadth to prepare MSW graduates for a wide range of social work jobs, but that also addresses students' and community agencies' demands for student…

  14. Conceptual Models for Search Engines

    NASA Astrophysics Data System (ADS)

    Hendry, D. G.; Efthimiadis, E. N.

    Search engines have entered popular culture. They touch people in diverse private and public settings and thus heighten the importance of such important social matters as information privacy and control, censorship, and equitable access. To fully benefit from search engines and to participate in debate about their merits, people necessarily appeal to their understandings for how they function. In this chapter we examine the conceptual understandings that people have of search engines by performing a content analysis on the sketches that 200 undergraduate and graduate students drew when asked to draw a sketch of how a search engine works. Analysis of the sketches reveals a diverse range of conceptual approaches, metaphors, representations, and misconceptions. On the whole, the conceptual models articulated by these students are simplistic. However, students with higher levels of academic achievement sketched more complete models. This research calls attention to the importance of improving students' technical knowledge of how search engines work so they can be better equipped to develop and advocate policies for how search engines should be embedded in, and restricted from, various private and public information settings.

  15. toolkit computational mesh conceptual model.

    SciTech Connect

    Baur, David G.; Edwards, Harold Carter; Cochran, William K.; Williams, Alan B.; Sjaardema, Gregory D.

    2010-03-01

    The Sierra Toolkit computational mesh is a software library intended to support massively parallel multi-physics computations on dynamically changing unstructured meshes. This domain of intended use is inherently complex due to distributed memory parallelism, parallel scalability, heterogeneity of physics, heterogeneous discretization of an unstructured mesh, and runtime adaptation of the mesh. Management of this inherent complexity begins with a conceptual analysis and modeling of this domain of intended use; i.e., development of a domain model. The Sierra Toolkit computational mesh software library is designed and implemented based upon this domain model. Software developers using, maintaining, or extending the Sierra Toolkit computational mesh library must be familiar with the concepts/domain model presented in this report.

  16. What Is "Advanced" in Generalist Practice? A Conceptual Discussion

    ERIC Educational Resources Information Center

    Lavitt, Melissa R.

    2009-01-01

    Advanced generalist practice is the fastest growing area of concentration for Master of Social Work (MSW) programs in the United States, yet a definition remains elusive. This article proposes that three key elements should be included within a conceptual schema of advanced generalist practice. Multidimensional problem-setting, self-reflective…

  17. WRAP 2A advanced conceptual design report comments

    SciTech Connect

    Lamberd, D.L.

    1994-10-04

    This report contains the compilation of the 393 comments that were submitted during the review of the Advanced Conceptual Design Report for the Waste Receiving and Processing Facility Module 2A. The report was prepared by Raytheon Engineers and Constructors, Inc. of Englewood, Colorado for the United States Department of Energy. The review was performed by a variety of organizations identified in the report. The comments were addressed first by the Westinghouse cognizant engineers and then by the Raytheon cognizant engineers, and incorporated into the final issue of the Advanced Conceptual Design Report.

  18. A Conceptual Data Model of Datum Systems

    PubMed Central

    McCaleb, Michael R.

    1999-01-01

    A new conceptual data model that addresses the geometric dimensioning and tolerancing concepts of datum systems, datums, datum features, datum targets, and the relationships among these concepts, is presented. Additionally, a portion of a related data model, Part 47 of STEP (ISO 10303-47), is reviewed and a comparison is made between it and the new conceptual data model.

  19. Conceptual and logical level of database modeling

    NASA Astrophysics Data System (ADS)

    Hunka, Frantisek; Matula, Jiri

    2016-06-01

    Conceptual and logical levels form the top most levels of database modeling. Usually, ORM (Object Role Modeling) and ER diagrams are utilized to capture the corresponding schema. The final aim of business process modeling is to store its results in the form of database solution. For this reason, value oriented business process modeling which utilizes ER diagram to express the modeling entities and relationships between them are used. However, ER diagrams form the logical level of database schema. To extend possibilities of different business process modeling methodologies, the conceptual level of database modeling is needed. The paper deals with the REA value modeling approach to business process modeling using ER-diagrams, and derives conceptual model utilizing ORM modeling approach. Conceptual model extends possibilities for value modeling to other business modeling approaches.

  20. Conceptualizing a Framework for Advanced Placement Statistics Teaching Knowledge

    ERIC Educational Resources Information Center

    Haines, Brenna

    2015-01-01

    The purpose of this article is to sketch a conceptualization of a framework for Advanced Placement (AP) Statistics Teaching Knowledge. Recent research continues to problematize the lack of knowledge and preparation among secondary level statistics teachers. The College Board's AP Statistics course continues to grow and gain popularity, but is a…

  1. Advanced wind turbine design studies: Advanced conceptual study

    NASA Astrophysics Data System (ADS)

    Hughes, P.; Sherwin, R.

    1994-08-01

    In conjunction with the US Department of Energy and the National Renewable Energy Laboratory's Advanced Wind Turbine Program, the Atlantic Orient Corporation developed preliminary designs for the next generation of wind turbines. These 50 kW and 350 kW turbines are based upon the concept of simplicity. By adhering to a design philosophy that emphasizes simplicity, we project that these turbines will produce energy at extremely competitive rates which will unlock the potential of wind energy domestically and internationally. The program consisted of three distinct phases. First, we evaluated the operational history of the Enertech 44 series wind turbines. As a result of this evaluation, we developed, in the second phase, a preliminary design for a new 50 kW turbine for the near-term market. In the third phase, we took a clean-sheet-of-paper approach to designing a 350 kW turbine focused on the mid-1990s utility market that incorporated past experience and advanced technology.

  2. Advanced wind turbine design studies: Advanced conceptual study. Final report

    SciTech Connect

    Hughes, P; Sherwin, R

    1994-08-01

    In conjunction with the US Department of Energy and the National Renewable Energy Laboratory`s Advanced Wind Turbine Program, the Atlantic Orient Corporation developed preliminary designs for the next generation of wind turbines. These 50 kW and 350 kW turbines are based upon the concept of simplicity. By adhering to a design philosophy that emphasizes simplicity, we project that these turbines will produce energy at extremely competitive rates which will unlock the potential of wind energy domestically and internationally. The program consisted of three distinct phases. First, we evaluated the operational history of the Enertech 44 series wind turbines. As a result of this evaluation, we developed, in the second phase, a preliminary design for a new 50 kW turbine for the near-term market. In the third phase, we took a clean-sheet-of-paper approach to designing a 350 kW turbine focused on the mid-1990s utility market that incorporated past experience and advanced technology.

  3. Forest fire advanced system technology (FFAST) conceptual design study

    NASA Technical Reports Server (NTRS)

    Nichols, J. David; Warren, John R.

    1987-01-01

    The National Aeronautics and Space Administration's Jet Propulsion Laboratory (JPL) and the U.S. Department of Agriculture (USDA) Forest Service completed a conceptual design study that defined an integrated forest fire detection and mapping system that will be based upon technology available in the 1990s. Potential system configuration options in emerging and advanced technologies related to the conceptual design were identified and recommended for inclusion as preferred system components. System component technologies identified for an end-to-end system include airborne mounted, thermal infrared (IR) linear array detectors, automatic onboard georeferencing and signal processing, geosynchronous satellite communications links, and advanced data integration and display. Potential system configuration options were developed and examined for possible inclusion in the preferred system configuration. The preferred system configuration will provide increased performance and be cost effective over the system currently in use. Forest fire management user requirements and the system component emerging technologies were the basis for the system configuration design. The conceptual design study defined the preferred system configuration that warrants continued refinement and development, examined economic aspects of the current and preferred system, and provided preliminary cost estimates for follow-on system prototype development.

  4. An Empirical Study of Enterprise Conceptual Modeling

    NASA Astrophysics Data System (ADS)

    Anaby-Tavor, Ateret; Amid, David; Fisher, Amit; Ossher, Harold; Bellamy, Rachel; Callery, Matthew; Desmond, Michael; Krasikov, Sophia; Roth, Tova; Simmonds, Ian; de Vries, Jacqueline

    Business analysts, business architects, and solution consultants use a variety of practices and methods in their quest to understand business. The resulting work products could end up being transitioned into the formal world of software requirement definitions or as recommendations for all kinds of business activities. We describe an empirical study about the nature of these methods, diagrams, and home-grown conceptual models as reflected in real practice at IBM. We identify the models as artifacts of "enterprise conceptual modeling". We study important features of these models, suggest practical classifications, and discuss their usage. Our survey shows that the "enterprise conceptual modeling" arena presents a variety of descriptive models, each used by a relatively small group of colleagues. Together they form a "long tail" that extends from "drawings" on one end to "standards" on the other.

  5. Formalizing Linguistic Conventions for Conceptual Models

    NASA Astrophysics Data System (ADS)

    Becker, Jörg; Delfmann, Patrick; Herwig, Sebastian; Lis, Łukasz; Stein, Armin

    A precondition for the appropriate analysis of conceptual models is not only their syntactic correctness but also their semantic comparability. Assuring comparability is challenging especially when models are developed by different persons. Empirical studies show that such models can vary heavily, especially in model element naming, even if they express the same issue. In contrast to most ontology-driven approaches proposing the resolution of these differences ex-post, we introduce an approach that avoids naming differences in conceptual models already during modeling. Therefore we formalize naming conventions combining domain thesauri and phrase structures based on a lin-guistic grammar. This allows for guiding modelers automatically during the modeling process using standardized labels for model elements. Our approach is generic, making it applicable for any modeling language.

  6. Conceptual design study: Forest Fire Advanced System Technology (FFAST)

    NASA Technical Reports Server (NTRS)

    Nichols, J. D.; Warren, J. R.

    1986-01-01

    An integrated forest fire detection and mapping system that will be based upon technology available in the 1990s was defined. Uncertainties in emerging and advanced technologies related to the conceptual design were identified and recommended for inclusion as preferred system components. System component technologies identified for an end-to-end system include thermal infrared, linear array detectors, automatic georeferencing and signal processing, geosynchronous satellite communication links, and advanced data integration and display. Potential system configuration options were developed and examined for possible inclusion in the preferred system configuration. The preferred system configuration will provide increased performance and be cost effective over the system currently in use. Forest fire management user requirements and the system component emerging technologies were the basis for the system configuration design. A preferred system configuration was defined that warrants continued refinement and development, examined economic aspects of the current and preferred system, and provided preliminary cost estimates for follow-on system prototype development.

  7. Conceptual frameworks and methods for advancing invasion ecology.

    PubMed

    Heger, Tina; Pahl, Anna T; Botta-Dukát, Zoltan; Gherardi, Francesca; Hoppe, Christina; Hoste, Ivan; Jax, Kurt; Lindström, Leena; Boets, Pieter; Haider, Sylvia; Kollmann, Johannes; Wittmann, Meike J; Jeschke, Jonathan M

    2013-09-01

    Invasion ecology has much advanced since its early beginnings. Nevertheless, explanation, prediction, and management of biological invasions remain difficult. We argue that progress in invasion research can be accelerated by, first, pointing out difficulties this field is currently facing and, second, looking for measures to overcome them. We see basic and applied research in invasion ecology confronted with difficulties arising from (A) societal issues, e.g., disparate perceptions of invasive species; (B) the peculiarity of the invasion process, e.g., its complexity and context dependency; and (C) the scientific methodology, e.g., imprecise hypotheses. To overcome these difficulties, we propose three key measures: (1) a checklist for definitions to encourage explicit definitions; (2) implementation of a hierarchy of hypotheses (HoH), where general hypotheses branch into specific and precisely testable hypotheses; and (3) platforms for improved communication. These measures may significantly increase conceptual clarity and enhance communication, thus advancing invasion ecology.

  8. A Conceptual Titan Orbiter Mission Using Advanced Radioisotope Power Systems

    NASA Technical Reports Server (NTRS)

    Abelson, Robert D.; Shirley, James H.; Spilker, Thomas R.

    2006-01-01

    This study details a conceptual follow-on Titan orbiter mission that would provide full global topographic coverage. surface imaging, and meteorological characterization of the atmosphere over a nominal 5-year science mission duration. The baseline power requirement is approx.1 kWe at EOM and is driven by a high power radar instrument that would provide 3-dimensional measurements of atmospheric clouds, precipitation, and surface topography. While this power level is moderately higher than that of the Cassini spacecraft. higher efficiency advanced RPSs could potentially reduce the plutonium usage to less than 1/3rd of that used on the Cassini spacecraft. The Titan Orbiter mission is assumed to launch in 2015. It would utilize advanced RPSs to provide all on-board power.

  9. Administrator Training and Development: Conceptual Model.

    ERIC Educational Resources Information Center

    Boardman, Gerald R.

    A conceptual model for an individualized training program for school administrators integrates processes, characteristics, and tasks through theory training and application. Based on an application of contingency theory, it provides a system matching up administrative candidates' needs in three areas (administrative process, administrative…

  10. Conceptual Models of Frontal Cyclones.

    ERIC Educational Resources Information Center

    Eagleman, Joe R.

    1981-01-01

    This discussion of weather models uses maps to illustrate the differences among three types of frontal cyclones (long wave, short wave, and troughs). Awareness of these cyclones can provide clues to atmospheric conditions which can lead toward accurate weather forecasting. (AM)

  11. A conceptual model for megaprogramming

    NASA Technical Reports Server (NTRS)

    Tracz, Will

    1990-01-01

    Megaprogramming is component-based software engineering and life-cycle management. Magaprogramming and its relationship to other research initiatives (common prototyping system/common prototyping language, domain specific software architectures, and software understanding) are analyzed. The desirable attributes of megaprogramming software components are identified and a software development model and resulting prototype megaprogramming system (library interconnection language extended by annotated Ada) are described.

  12. The conceptualization model problem—surprise

    NASA Astrophysics Data System (ADS)

    Bredehoeft, John

    2005-03-01

    The foundation of model analysis is the conceptual model. Surprise is defined as new data that renders the prevailing conceptual model invalid; as defined here it represents a paradigm shift. Limited empirical data indicate that surprises occur in 20-30% of model analyses. These data suggest that groundwater analysts have difficulty selecting the appropriate conceptual model. There is no ready remedy to the conceptual model problem other than (1) to collect as much data as is feasible, using all applicable methods—a complementary data collection methodology can lead to new information that changes the prevailing conceptual model, and (2) for the analyst to remain open to the fact that the conceptual model can change dramatically as more information is collected. In the final analysis, the hydrogeologist makes a subjective decision on the appropriate conceptual model. The conceptualization problem does not render models unusable. The problem introduces an uncertainty that often is not widely recognized. Conceptual model uncertainty is exacerbated in making long-term predictions of system performance. C'est le modèle conceptuel qui se trouve à base d'une analyse sur un modèle. On considère comme une surprise lorsque le modèle est invalidé par des données nouvelles; dans les termes définis ici la surprise est équivalente à un change de paradigme. Des données empiriques limitées indiquent que les surprises apparaissent dans 20 à 30% des analyses effectuées sur les modèles. Ces données suggèrent que l'analyse des eaux souterraines présente des difficultés lorsqu'il s'agit de choisir le modèle conceptuel approprié. Il n'existe pas un autre remède au problème du modèle conceptuel que: (1) rassembler autant des données que possible en utilisant toutes les méthodes applicables—la méthode des données complémentaires peut conduire aux nouvelles informations qui vont changer le modèle conceptuel, et (2) l'analyste doit rester ouvert au fait

  13. Conceptual design study of advanced acoustic-composite nacelles

    NASA Technical Reports Server (NTRS)

    Nordstrom, K. E.; Marsh, A. H.; Sargisson, D. F.

    1975-01-01

    Conceptual studies were conducted to assess the impact of incorporating advanced technologies in the nacelles of a current wide-bodied transport and an advanced technology transport. The improvement possible in the areas of fuel consumption, flyover noise levels, airplane weight, manufacturing costs, and airplane operating cost were evaluated for short and long-duct nacelles. Use of composite structures for acoustic duct linings in the fan inlet and exhaust ducts was considered as well as for other nacelle components. For the wide-bodied transport, the use of a long-duct nacelle with an internal mixer nozzle in the primary exhaust showed significant improvement in installed specific fuel consumption and airplane direct operating costs compared to the current short-duct nacelle. The long-duct mixed-flow nacelle is expected to achieve significant reductions in jet noise during takeoff and in turbo-machinery noise during landing approach. Recommendations were made of the technology development needed to achieve the potential fuel conservation and noise reduction benefits.

  14. A Conceptual Model of Learning Networks

    NASA Astrophysics Data System (ADS)

    Koper, Rob

    In the TENCompetence project a set of UML models (Booch et al. 1999) have been developed to specify the core concepts for Learning Networks Services that support professional competence development. The three most important, high-level models are (a) the use case model, (b) the conceptual model, and (c) the domain model. The first model identifies the primary use cases we need in order to support professional competence development. The second model describes the concept of competence and competence development from a theoretical point of view. What is a competence? How does it relate to the cognitive system of an actor? How are competences developed? The third model is a UML Domain Model that defines, among other things, the components of a Learning Network, defines the concepts and relationships between the concepts in a Learning Network and provides a starting point for the design of the overall architecture for Learning Network Services, including the data model.

  15. Critical conceptualism in environmental modeling and prediction.

    PubMed

    Christakos, G

    2003-10-15

    Many important problems in environmental science and engineering are of a conceptual nature. Research and development, however, often becomes so preoccupied with technical issues, which are themselves fascinating, that it neglects essential methodological elements of conceptual reasoning and theoretical inquiry. This work suggests that valuable insight into environmental modeling can be gained by means of critical conceptualism which focuses on the software of human reason and, in practical terms, leads to a powerful methodological framework of space-time modeling and prediction. A knowledge synthesis system develops the rational means for the epistemic integration of various physical knowledge bases relevant to the natural system of interest in order to obtain a realistic representation of the system, provide a rigorous assessment of the uncertainty sources, generate meaningful predictions of environmental processes in space-time, and produce science-based decisions. No restriction is imposed on the shape of the distribution model or the form of the predictor (non-Gaussian distributions, multiple-point statistics, and nonlinear models are automatically incorporated). The scientific reasoning structure underlying knowledge synthesis involves teleologic criteria and stochastic logic principles which have important advantages over the reasoning method of conventional space-time techniques. Insight is gained in terms of real world applications, including the following: the study of global ozone patterns in the atmosphere using data sets generated by instruments on board the Nimbus 7 satellite and secondary information in terms of total ozone-tropopause pressure models; the mapping of arsenic concentrations in the Bangladesh drinking water by assimilating hard and soft data from an extensive network of monitoring wells; and the dynamic imaging of probability distributions of pollutants across the Kalamazoo river. PMID:14594379

  16. Conceptual Frameworks in the Doctoral Research Process: A Pedagogical Model

    ERIC Educational Resources Information Center

    Berman, Jeanette; Smyth, Robyn

    2015-01-01

    This paper contributes to consideration of the role of conceptual frameworks in the doctoral research process. Through reflection on the two authors' own conceptual frameworks for their doctoral studies, a pedagogical model has been developed. The model posits the development of a conceptual framework as a core element of the doctoral…

  17. A Structural Equation Model of Conceptual Change in Physics

    ERIC Educational Resources Information Center

    Taasoobshirazi, Gita; Sinatra, Gale M.

    2011-01-01

    A model of conceptual change in physics was tested on introductory-level, college physics students. Structural equation modeling was used to test hypothesized relationships among variables linked to conceptual change in physics including an approach goal orientation, need for cognition, motivation, and course grade. Conceptual change in physics…

  18. Social Determinants and Health Behaviors: Conceptual Frames and Empirical Advances

    PubMed Central

    Short, Susan E.; Mollborn, Stefanie

    2015-01-01

    Health behaviors shape health and well-being in individuals and populations. Drawing on recent research, we review applications of the widely applied “social determinants” approach to health behaviors. This approach shifts the lens from individual attribution and responsibility to societal organization and the myriad institutions, structures, inequalities, and ideologies undergirding health behaviors. Recent scholarship integrates a social determinants perspective with biosocial approaches to health behavior dynamics. Empirical advances model feedback among social, psychological and biological factors. Health behaviors are increasingly recognized as multidimensional and embedded in health lifestyles, varying over the life course and across place and reflecting dialectic between structure and agency that necessitates situating individuals in context. Advances in measuring and modeling health behaviors promise to enhance representations of this complexity. PMID:26213711

  19. A Conceptual Model of Referee Efficacy

    PubMed Central

    Guillén, Félix; Feltz, Deborah L.

    2010-01-01

    This paper presents a conceptual model of referee efficacy, defines the concept, proposes sources of referee specific efficacy information, and suggests consequences of having high or low referee efficacy. Referee efficacy is defined as the extent to which referees believe they have the capacity to perform successfully in their job. Referee efficacy beliefs are hypothesized to be influenced by mastery experiences, referee knowledge/education, support from significant others, physical/mental preparedness, environmental comfort, and perceived anxiety. In turn, referee efficacy beliefs are hypothesized to influence referee performance, referee stress, athlete rule violations, athlete satisfaction, and co-referee satisfaction. PMID:21713174

  20. Propulsion System Models for Rotorcraft Conceptual Design

    NASA Technical Reports Server (NTRS)

    Johnson, Wayne

    2014-01-01

    The conceptual design code NDARC (NASA Design and Analysis of Rotorcraft) was initially implemented to model conventional rotorcraft propulsion systems, consisting of turboshaft engines burning jet fuel, connected to one or more rotors through a mechanical transmission. The NDARC propulsion system representation has been extended to cover additional propulsion concepts, including electric motors and generators, rotor reaction drive, turbojet and turbofan engines, fuel cells and solar cells, batteries, and fuel (energy) used without weight change. The paper describes these propulsion system components, the architecture of their implementation in NDARC, and the form of the models for performance and weight. Requirements are defined for improved performance and weight models of the new propulsion system components. With these new propulsion models, NDARC can be used to develop environmentally-friendly rotorcraft designs.

  1. Multi-level Conceptual Modeling and OWL

    NASA Astrophysics Data System (ADS)

    Neumayr, Bernd; Schrefl, Michael

    Ontological metamodeling or multilevel-modeling refers to describing complex domains at multiple levels of abstraction, especially in domains where the borderline between individuals and classes is not clear cut. Punning in OWL2 provides decideable metamodeling support by allowing to use one symbol both as identifier of a class as well as of an individual. In conceptual modeling more powerful approaches to ontological metamodeling exist: materialization, potency-based deep instantiation, and m-objects/m-relationships. These approaches not only support to treat classes as individuals but also to describe domain concepts with members at multiple levels of abstraction. Based on a mapping from m-objects/m-relationships to OWL we show how to transfer these ideas from conceptual modeling to ontology engineering. Therefore we have to combine closed world and open world reasoning. We provide semantic-preserving mappings from m-objects and m-relationships to the decideable fragment of OWL, extended by integrity constraints, and sketch basic tool support for applying this approach.

  2. CONCEPTUAL MODELS FOR THE LASSEN HYDROTHERMAL SYSTEM.

    USGS Publications Warehouse

    Ingebritsen, S.E.; Sorey, M.L.

    1987-01-01

    The Lassen hydrothermal system, like a number of other systems in regions of moderate to great topographic relief, includes steam-heated features at higher elevations and high-chloride springs at lower elevations, connected to and fed by a single circulation system at depth. Two conceptual models for such systems are presented. They are similar in several ways: however, there are basic differences in terms of the nature and extent of vapor-dominated conditions beneath the steam-heated features. For some Lassen-like systems, these differences could have environmental and economic implications. Available data do not make it possible to establish a single preferred model for the Lassen system, and the actual system is complex enough that both models may apply to different parts of the system.

  3. A conceptual holding model for veterinary applications.

    PubMed

    Ferrè, Nicola; Kuhn, Werner; Rumor, Massimo; Marangon, Stefano

    2014-05-01

    Spatial references are required when geographical information systems (GIS) are used for the collection, storage and management of data. In the veterinary domain, the spatial component of a holding (of animals) is usually defined by coordinates, and no other relevant information needs to be interpreted or used for manipulation of the data in the GIS environment provided. Users trying to integrate or reuse spatial data organised in such a way, frequently face the problem of data incompatibility and inconsistency. The root of the problem lies in differences with respect to syntax as well as variations in the semantic, spatial and temporal representations of the geographic features. To overcome these problems and to facilitate the inter-operability of different GIS, spatial data must be defined according to a \\"schema\\" that includes the definition, acquisition, analysis, access, presentation and transfer of such data between different users and systems. We propose an application \\"schema\\" of holdings for GIS applications in the veterinary domain according to the European directive framework (directive 2007/2/EC--INSPIRE). The conceptual model put forward has been developed at two specific levels to produce the essential and the abstract model, respectively. The former establishes the conceptual linkage of the system design to the real world, while the latter describes how the system or software works. The result is an application \\"schema\\" that formalises and unifies the information-theoretic foundations of how to spatially represent a holding in order to ensure straightforward information-sharing within the veterinary community. PMID:24893036

  4. Detecting hydrological changes through conceptual model

    NASA Astrophysics Data System (ADS)

    Viola, Francesco; Caracciolo, Domenico; Pumo, Dario; Francipane, Antonio; Valerio Noto, Leonardo

    2015-04-01

    Natural changes and human modifications in hydrological systems coevolve and interact in a coupled and interlinked way. If, on one hand, climatic changes are stochastic, non-steady, and affect the hydrological systems, on the other hand, human-induced changes due to over-exploitation of soils and water resources modifies the natural landscape, water fluxes and its partitioning. Indeed, the traditional assumption of static systems in hydrological analysis, which has been adopted for long time, fails whenever transient climatic conditions and/or land use changes occur. Time series analysis is a way to explore environmental changes together with societal changes; unfortunately, the not distinguishability between causes restrict the scope of this method. In order to overcome this limitation, it is possible to couple time series analysis with an opportune hydrological model, such as a conceptual hydrological model, which offers a schematization of complex dynamics acting within a basin. Assuming that model parameters represent morphological basin characteristics and that calibration is a way to detect hydrological signature at a specific moment, it is possible to argue that calibrating the model over different time windows could be a method for detecting potential hydrological changes. In order to test the capabilities of a conceptual model in detecting hydrological changes, this work presents different "in silico" experiments. A synthetic-basin is forced with an ensemble of possible future scenarios generated with a stochastic weather generator able to simulate steady and non-steady climatic conditions. The experiments refer to Mediterranean climate, which is characterized by marked seasonality, and consider the outcomes of the IPCC 5th report for describing climate evolution in the next century. In particular, in order to generate future climate change scenarios, a stochastic downscaling in space and time is carried out using realizations of an ensemble of General

  5. Turnaround Time Modeling for Conceptual Rocket Engines

    NASA Technical Reports Server (NTRS)

    Nix, Michael; Staton, Eric J.

    2004-01-01

    Recent years have brought about a paradigm shift within NASA and the Space Launch Community regarding the performance of conceptual design. Reliability, maintainability, supportability, and operability are no longer effects of design; they have moved to the forefront and are affecting design. A primary focus of this shift has been a planned decrease in vehicle turnaround time. Potentials for instituting this decrease include attacking the issues of removing, refurbishing, and replacing the engines after each flight. less, it is important to understand the operational affects of an engine on turnaround time, ground support personnel and equipment. One tool for visualizing this relationship involves the creation of a Discrete Event Simulation (DES). A DES model can be used to run a series of trade studies to determine if the engine is meeting its requirements, and, if not, what can be altered to bring it into compliance. Using DES, it is possible to look at the ways in which labor requirements, parallel maintenance versus serial maintenance, and maintenance scheduling affect the overall turnaround time. A detailed DES model of the Space Shuttle Main Engines (SSME) has been developed. Trades may be performed using the SSME Processing Model to see where maintenance bottlenecks occur, what the benefits (if any) are of increasing the numbers of personnel, or the number and location of facilities, in addition to trades previously mentioned, all with the goal of optimizing the operational turnaround time and minimizing operational cost. The SSME Processing Model was developed in such a way that it can easily be used as a foundation for developing DES models of other operational or developmental reusable engines. Performing a DES on a developmental engine during the conceptual phase makes it easier to affect the design and make changes to bring about a decrease in turnaround time and costs.

  6. A conceptual model of an Arctic sea

    NASA Astrophysics Data System (ADS)

    St-Laurent, P.; Straneo, F.; Barber, D. G.

    2012-06-01

    We propose a conceptual model for an Arctic sea that is driven by river runoff, atmospheric fluxes, sea ice melt/growth, and winds. The model domain is divided into two areas, the interior and boundary regions, that are coupled through Ekman and eddy fluxes of buoyancy. The model is applied to Hudson and James Bays (HJB, a large inland basin in northeastern Canada) for the period 1979-2007. Several yearlong records from instruments moored within HJB show that the model results are consistent with the real system. The model notably reproduces the seasonal migration of the halocline, the baroclinic boundary current, spatial variability of freshwater content, and the fall maximum in freshwater export. The simulations clarify the important differences in the freshwater balance of the western and eastern sides of HJB. The significant role played by the boundary current in the freshwater budget of the system, and its sensitivity to the wind-forcing, are also highlighted by the simulations and new data analyses. We conclude that the model proposed is useful for the interpretation of observed data from Arctic seas and model outputs from more complex coupled/climate models.

  7. Multimorbidity: conceptual basis, epidemiological models and measurement challenges.

    PubMed

    Fernández-Niño, Julián Alfredo; Bustos-Vázquez, Eduardo

    2016-01-01

    The growing number of patients with complex clinical profiles related to chronic diseases has contributed to the increasingly widespread use of the term 'multimorbidity'. A suitable measurement of this condition is essential to epidemiological studies considering that it represents a challenge for the clinical management of patients as well as for health systems and epidemiological investigations. In this context, the present essay reviews the conceptual proposals behind the measurement of multimorbidity including the epidemiological and methodological challenges it involves. We discuss classical definitions of comorbidity, how they differ from the concept of multimorbidity, and their roles in epidemiological studies. The various conceptual models that contribute to the operational definitions and strategies to measure this variable are also presented. The discussion enabled us to identify a significant gap between the modern conceptual development of multimorbidity and the operational definitions. This gap exists despite the theoretical developments that have occurred in the classical concept of comorbidity to arrive to the modern and multidimensional conception of multimorbidty. Measurement strategies, however, have not kept pace with this advance. Therefore, new methodological proposals need to be developed in order to obtain information regarding the actual impact on individuals' health and its implications for public health. PMID:27622480

  8. Multimorbidity: conceptual basis, epidemiological models and measurement challenges.

    PubMed

    Fernández-Niño, Julián Alfredo; Bustos-Vázquez, Eduardo

    2016-06-03

    The growing number of patients with complex clinical profiles related to chronic diseases has contributed to the increasingly widespread use of the term 'multimorbidity'. A suitable measurement of this condition is essential to epidemiological studies considering that it represents a challenge for the clinical management of patients as well as for health systems and epidemiological investigations. In this context, the present essay reviews the conceptual proposals behind the measurement of multimorbidity including the epidemiological and methodological challenges it involves. We discuss classical definitions of comorbidity, how they differ from the concept of multimorbidity, and their roles in epidemiological studies. The various conceptual models that contribute to the operational definitions and strategies to measure this variable are also presented. The discussion enabled us to identify a significant gap between the modern conceptual development of multimorbidity and the operational definitions. This gap exists despite the theoretical developments that have occurred in the classical concept of comorbidity to arrive to the modern and multidimensional conception of multimorbidty. Measurement strategies, however, have not kept pace with this advance. Therefore, new methodological proposals need to be developed in order to obtain information regarding the actual impact on individuals' health and its implications for public health.

  9. A conceptual model of intentional comfort touch.

    PubMed

    Connor, Ann; Howett, Maeve

    2009-06-01

    This article discusses the application and integration of intentional comfort touch as a holistic nursing practice. A review of the literature on touch and its related concepts is included. Although nurses use touch frequently in patient encounters, it is not always used intentionally or deliberately to enhance care. The article compares and contrasts intentional comfort touch with nonintentional or procedural touch. The use of intentional comfort touch in innovative clinical settings with diverse and at-risk populations is described. Based on clinical experiences and the current literature, a conceptual model of intentional comfort touch is proposed. The application of touch is discussed as is the meaning and importance of intentional touch for students, faculty, and patients. PMID:19443699

  10. Conceptual models as hypotheses in monitoring urban landscapes.

    PubMed

    Lookingbill, Todd R; Gardner, Robert H; Townsend, Philip A; Carter, Shawn L

    2007-08-01

    Many problems and challenges of ecosystem management currently are driven by the rapid pace and spatial extent of landscape change. Parks and reserves within areas of high human population density are especially challenged to meet the recreational needs of local populations and to preserve valued environmental resources. The complex problem of managing multiple objectives and multiple resources requires an enormous quantity of information, and conceptual models have been proposed as tools for organizing and interpreting this information. Academics generally prefer a bottom-up approach to model construction that emphasizes ecologic theory and process, whereas managers often use a top-down approach that takes advantage of existing information to address more pragmatic objectives. The authors propose a formal process for developing, applying, and testing conceptual models to be used in landscape monitoring that reconciles these seemingly opposing perspectives. The four-step process embraces the role of hypothesis testing in the development of models and evaluation of their utility. An example application of the process to a network of national parks in and around Washington, DC illustrates the ability of the approach to systematically identify monitoring data that would both advance ecologic theory and inform management decisions.

  11. Equivalent plate modeling for conceptual design of aircraft wing structures

    NASA Technical Reports Server (NTRS)

    Giles, Gary L.

    1995-01-01

    This paper describes an analysis method that generates conceptual-level design data for aircraft wing structures. A key requirement is that this data must be produced in a timely manner so that is can be used effectively by multidisciplinary synthesis codes for performing systems studies. Such a capability is being developed by enhancing an equivalent plate structural analysis computer code to provide a more comprehensive, robust and user-friendly analysis tool. The paper focuses on recent enhancements to the Equivalent Laminated Plate Solution (ELAPS) analysis code that significantly expands the modeling capability and improves the accuracy of results. Modeling additions include use of out-of-plane plate segments for representing winglets and advanced wing concepts such as C-wings along with a new capability for modeling the internal rib and spar structure. The accuracy of calculated results is improved by including transverse shear effects in the formulation and by using multiple sets of assumed displacement functions in the analysis. Typical results are presented to demonstrate these new features. Example configurations include a C-wing transport aircraft, a representative fighter wing and a blended-wing-body transport. These applications are intended to demonstrate and quantify the benefits of using equivalent plate modeling of wing structures during conceptual design.

  12. Conceptual models as hypotheses in monitoring urban landscapes.

    PubMed

    Lookingbill, Todd R; Gardner, Robert H; Townsend, Philip A; Carter, Shawn L

    2007-08-01

    Many problems and challenges of ecosystem management currently are driven by the rapid pace and spatial extent of landscape change. Parks and reserves within areas of high human population density are especially challenged to meet the recreational needs of local populations and to preserve valued environmental resources. The complex problem of managing multiple objectives and multiple resources requires an enormous quantity of information, and conceptual models have been proposed as tools for organizing and interpreting this information. Academics generally prefer a bottom-up approach to model construction that emphasizes ecologic theory and process, whereas managers often use a top-down approach that takes advantage of existing information to address more pragmatic objectives. The authors propose a formal process for developing, applying, and testing conceptual models to be used in landscape monitoring that reconciles these seemingly opposing perspectives. The four-step process embraces the role of hypothesis testing in the development of models and evaluation of their utility. An example application of the process to a network of national parks in and around Washington, DC illustrates the ability of the approach to systematically identify monitoring data that would both advance ecologic theory and inform management decisions. PMID:17562105

  13. Conceptual Models as Hypotheses in Monitoring Urban Landscapes

    NASA Astrophysics Data System (ADS)

    Lookingbill, Todd R.; Gardner, Robert H.; Townsend, Philip A.; Carter, Shawn L.

    2007-08-01

    Many problems and challenges of ecosystem management currently are driven by the rapid pace and spatial extent of landscape change. Parks and reserves within areas of high human population density are especially challenged to meet the recreational needs of local populations and to preserve valued environmental resources. The complex problem of managing multiple objectives and multiple resources requires an enormous quantity of information, and conceptual models have been proposed as tools for organizing and interpreting this information. Academics generally prefer a bottom-up approach to model construction that emphasizes ecologic theory and process, whereas managers often use a top-down approach that takes advantage of existing information to address more pragmatic objectives. The authors propose a formal process for developing, applying, and testing conceptual models to be used in landscape monitoring that reconciles these seemingly opposing perspectives. The four-step process embraces the role of hypothesis testing in the development of models and evaluation of their utility. An example application of the process to a network of national parks in and around Washington, DC illustrates the ability of the approach to systematically identify monitoring data that would both advance ecologic theory and inform management decisions.

  14. NADM Conceptual Model 1.0 -- A Conceptual Model for Geologic Map Information

    USGS Publications Warehouse

    ,

    2004-01-01

    Executive Summary -- The NADM Data Model Design Team was established in 1999 by the North American Geologic Map Data Model Steering Committee (NADMSC) with the purpose of drafting a geologic map data model for consideration as a standard for developing interoperable geologic map-centered databases by state, provincial, and federal geological surveys. The model is designed to be a technology-neutral conceptual model that can form the basis for a web-based interchange format using evolving information technology (e.g., XML, RDF, OWL), and guide implementation of geoscience databases in a common conceptual framework. The intended purpose is to allow geologic information sharing between geologic map data providers and users, independent of local information system implementation. The model emphasizes geoscience concepts and relationships related to information presented on geologic maps. Design has been guided by an informal requirements analysis, documentation of existing databases, technology developments, and other standardization efforts in the geoscience and computer-science communities. A key aspect of the model is the notion that representation of the conceptual framework (ontology) that underlies geologic map data must be part of the model, because this framework changes with time and understanding, and varies between information providers. The top level of the model distinguishes geologic concepts, geologic representation concepts, and metadata. The geologic representation part of the model provides a framework for representing the ontology that underlies geologic map data through a controlled vocabulary, and for establishing the relationships between this vocabulary and a geologic map visualization or portrayal. Top-level geologic classes in the model are Earth material (substance), geologic unit (parts of the Earth), geologic age, geologic structure, fossil, geologic process, geologic relation, and geologic event.

  15. A conceptual, distributed snow redistribution model

    NASA Astrophysics Data System (ADS)

    Frey, S.; Holzmann, H.

    2015-11-01

    When applying conceptual hydrological models using a temperature index approach for snowmelt to high alpine areas often accumulation of snow during several years can be observed. Some of the reasons why these "snow towers" do not exist in nature are vertical and lateral transport processes. While snow transport models have been developed using grid cell sizes of tens to hundreds of square metres and have been applied in several catchments, no model exists using coarser cell sizes of 1 km2, which is a common resolution for meso- and large-scale hydrologic modelling (hundreds to thousands of square kilometres). In this paper we present an approach that uses only gravity and snow density as a proxy for the age of the snow cover and land-use information to redistribute snow in alpine basins. The results are based on the hydrological modelling of the Austrian Inn Basin in Tyrol, Austria, more specifically the Ötztaler Ache catchment, but the findings hold for other tributaries of the river Inn. This transport model is implemented in the distributed rainfall-runoff model COSERO (Continuous Semi-distributed Runoff). The results of both model concepts with and without consideration of lateral snow redistribution are compared against observed discharge and snow-covered areas derived from MODIS satellite images. By means of the snow redistribution concept, snow accumulation over several years can be prevented and the snow depletion curve compared with MODIS (Moderate Resolution Imaging Spectroradiometer) data could be improved, too. In a 7-year period the standard model would lead to snow accumulation of approximately 2900 mm SWE (snow water equivalent) in high elevated regions whereas the updated version of the model does not show accumulation and does also predict discharge with more accuracy leading to a Kling-Gupta efficiency of 0.93 instead of 0.9. A further improvement can be shown in the comparison of MODIS snow cover data and the calculated depletion curve, where

  16. Showing Automatically Generated Students' Conceptual Models to Students and Teachers

    ERIC Educational Resources Information Center

    Perez-Marin, Diana; Pascual-Nieto, Ismael

    2010-01-01

    A student conceptual model can be defined as a set of interconnected concepts associated with an estimation value that indicates how well these concepts are used by the students. It can model just one student or a group of students, and can be represented as a concept map, conceptual diagram or one of several other knowledge representation…

  17. Conceptual Model Learning Objects and Design Recommendations for Small Screens

    ERIC Educational Resources Information Center

    Churchill, Daniel

    2011-01-01

    This article presents recommendations for the design of conceptual models for applications via handheld devices such as personal digital assistants and some mobile phones. The recommendations were developed over a number of years through experience that involves design of conceptual models, and applications of these multimedia representations with…

  18. Advanced conceptual design report. Phase II. Liquid effluent treatment and disposal Project W-252

    SciTech Connect

    1995-01-31

    This Advanced Conceptual Design Report (ACDR) provides a documented review and analysis of the Conceptual Design Report (CDR), WHC-SD-W252-CDR-001, June 30, 1993. The ACDR provides further design evaluation of the major design approaches and uncertainties identified in the original CDR. The ACDR will provide a firmer basis for the both the design approach and the associated planning for the performance of the Definitive Design phase of the project.

  19. Conceptual model for heart failure disease management.

    PubMed

    Andrikopoulou, Efstathia; Abbate, Kariann; Whellan, David J

    2014-03-01

    The objective of this review is to propose a conceptual model for heart failure (HF) disease management (HFDM) and to define the components of an efficient HFDM plan in reference to this model. Articles that evaluated 1 or more of the following aspects of HFDM were reviewed: (1) outpatient clinic follow-up; (2) self-care interventions to enhance patient skills; and (3) remote evaluation of worsening HF either using structured telephone support (STS) or by monitoring device data (telemonitoring). The success of programs in reducing readmissions and mortality were mixed. Outpatient follow-up programs generally resulted in improved outcomes, including decreased readmissions. Based on 1 meta-analysis, specialty clinics improved outcomes and nonspecialty clinics did not. Results from self-care programs were inconsistent and might have been affected by patient cognitive status and educational level, and intervention intensity. Telemonitoring, despite initially promising meta-analyses demonstrating a decrease in the number and duration of HF-related readmissions and all-cause mortality rates at follow-up, has not been shown in randomized trials to consistently reduce readmissions or mortality. However, evidence from device monitoring trials in particular might have been influenced by technology and design issues that might be rectified in future trials. Results from the literature suggest that the ideal HFDM plan would include outpatient follow-up at an HF specialty clinic and continuous education to improve patient self-care. The end result of this plan would lead to better understanding on the part of the patient and improved patient ability to recognize and respond to signs of decompensation.

  20. Conceptual and Numerical Models for UZ Flow and Transport

    SciTech Connect

    H. Liu

    2000-03-03

    The purpose of this Analysis/Model Report (AMR) is to document the conceptual and numerical models used for modeling of unsaturated zone (UZ) fluid (water and air) flow and solute transport processes. This is in accordance with ''AMR Development Plan for U0030 Conceptual and Numerical Models for Unsaturated Zone (UZ) Flow and Transport Processes, Rev 00''. The conceptual and numerical modeling approaches described in this AMR are used for models of UZ flow and transport in fractured, unsaturated rock under ambient and thermal conditions, which are documented in separate AMRs. This AMR supports the UZ Flow and Transport Process Model Report (PMR), the Near Field Environment PMR, and the following models: Calibrated Properties Model; UZ Flow Models and Submodels; Mountain-Scale Coupled Processes Model; Thermal-Hydrologic-Chemical (THC) Seepage Model; Drift Scale Test (DST) THC Model; Seepage Model for Performance Assessment (PA); and UZ Radionuclide Transport Models.

  1. Advanced Turbine Systems (ATS) program conceptual design and product development

    SciTech Connect

    1996-08-31

    Achieving the Advanced Turbine Systems (ATS) goals of 60% efficiency, single-digit NO{sub x}, and 10% electric power cost reduction imposes competing characteristics on the gas turbine system. Two basic technical issues arise from this. The turbine inlet temperature of the gas turbine must increase to achieve both efficiency and cost goals. However, higher temperatures move in the direction of increased NO{sub x} emission. Improved coatings and materials technologies along with creative combustor design can result in solutions to achieve the ultimate goal. GE`s view of the market, in conjunction with the industrial and utility objectives, requires the development of Advanced Gas Turbine Systems which encompass two potential products: a new aeroderivative combined-cycle system for the industrial market, and a combined-cycle system for the utility sector that is based on an advanced frame machine. The GE Advanced Gas Turbine Development program is focused on two specific products: (1) a 70 MW class industrial gas turbine based on the GE90 core technology utilizing an innovative air cooling methodology; (2) a 200 MW class utility gas turbine based on an advanced Ge heavy-duty machine utilizing advanced cooling and enhancement in component efficiency. Both of these activities required the identification and resolution of technical issues critical to achieving ATS goals. The emphasis for the industrial ATS was placed upon innovative cycle design and low emission combustion. The emphasis for the utility ATS was placed on developing a technology base for advanced turbine cooling, while utilizing demonstrated and planned improvements in low emission combustion. Significant overlap in the development programs will allow common technologies to be applied to both products. GE Power Systems is solely responsible for offering GE products for the industrial and utility markets.

  2. Model of Conceptual Change for INQPRO: A Bayesian Network Approach

    ERIC Educational Resources Information Center

    Ting, Choo-Yee; Sam, Yok-Cheng; Wong, Chee-Onn

    2013-01-01

    Constructing a computational model of conceptual change for a computer-based scientific inquiry learning environment is difficult due to two challenges: (i) externalizing the variables of conceptual change and its related variables is difficult. In addition, defining the causal dependencies among the variables is also not trivial. Such difficulty…

  3. Advanced Concept Modeling

    NASA Technical Reports Server (NTRS)

    Chaput, Armand; Johns, Zachary; Hodges, Todd; Selfridge, Justin; Bevirt, Joeben; Ahuja, Vivek

    2015-01-01

    Advanced Concepts Modeling software validation, analysis, and design. This was a National Institute of Aerospace contract with a lot of pieces. Efforts ranged from software development and validation for structures and aerodynamics, through flight control development, and aeropropulsive analysis, to UAV piloting services.

  4. ADVANCED TURBINE SYSTEM CONCEPTUAL DESIGN AND PRODUCT DEVELOPMENT - Final Report

    SciTech Connect

    Albrecht H. Mayer

    2000-07-15

    Asea Brown Boveri (ABB) has completed its technology based program. The results developed under Work Breakdown Structure (WBS) 8, concentrated on technology development and demonstration have been partially implemented in newer turbine designs. A significant improvement in heat rate and power output has been demonstrated. ABB will use the knowledge gained to further improve the efficiency of its Advanced Cycle System, which has been developed and introduced into the marked out side ABB's Advanced Turbine System (ATS) activities. The technology will lead to a power plant design that meets the ATS performance goals of over 60% plant efficiency, decreased electricity costs to consumers and lowest emissions.

  5. Challenges in Requirements Engineering: A Research Agenda for Conceptual Modeling

    NASA Astrophysics Data System (ADS)

    March, Salvatore T.; Allen, Gove N.

    Domains for which information systems are developed deal primarily with social constructions—conceptual objects and attributes created by human intentions and for human purposes. Information systems play an active role in these domains. They document the creation of new conceptual objects, record and ascribe values to their attributes, initiate actions within the domain, track activities performed, and infer conclusions based on the application of rules that govern how the domain is affected when socially-defined and identified causal events occur. Emerging applications of information technologies evaluate such business rules, learn from experience, and adapt to changes in the domain. Conceptual modeling grammars aimed at representing their system requirements must include conceptual objects, socially-defined events, and the rules pertaining to them. We identify challenges to conceptual modeling research and pose an ontology of the artificial as a step toward meeting them.

  6. An Integrative-Interactive Conceptual Model for Curriculum Development.

    ERIC Educational Resources Information Center

    Al-Ibrahim, Abdul Rahman H.

    1982-01-01

    The Integrative-Interactive Conceptual Model for Curriculum Development calls for curriculum reform and innovation to be cybernetic so that all aspects of curriculum planning get adequate attention. (CJ)

  7. Conceptual Model of Multidimensional Marketing Information System

    NASA Astrophysics Data System (ADS)

    Kriksciuniene, Dalia; Urbanskiene, Ruta

    This article is aimed to analyse, why the information systems at the enterprise not always satisfy the expectations of marketing management specialists. The computerized systems more and more successfully serve information needs of those areas of enterprise management, where they can create the information equivalent of real management processes. Yet their inability to effectively fulfill marketing needs indicate the gaps not only in ability to structure marketing processes, but in the conceptual development of marketing information systems (MkIS) as well.

  8. A Conceptual Venus Rover Mission Using Advanced Radioisotope Power Systems

    NASA Astrophysics Data System (ADS)

    Evans, Michael; Shirley, James H.; Abelson, Robert Dean

    2006-01-01

    This concept study demonstrates that a long lived Venus rover mission could be enabled by a novel application of advanced RPS technology. General Purpose Heat Source (GPHS) modules would be employed to drive an advanced thermoacoustic Stirling engine, pulse tube cooler and linear alternator that provides electric power and cooling for the rover. The Thermoacoustic Stirling Heat Engine (TASHE) is a system for converting high-temperature heat into acoustic power which then drives linear alternators and a pulse tube cooler to provide both electric power and coolin6g for the rover. A small design team examined this mission concept focusing on the feasibility of using the TASHE system in this hostile environment. A rover design is described that would provide a mobile platform for science measurements on the Venus surface for 60 days, with the potential of operating well beyond that. A suite of science instruments is described that collects data on atmospheric and surface composition, surface stratigraphy, and subsurface structure. An Earth-Venus-Venus trajectory would be used to deliver the rover to a low entry angle allowing an inflated ballute to provide a low deceleration and low heat descent to the surface. All rover systems would be housed in a pressure vessel in vacuum with the internal temperature maintained by the TASHE at under 50 °C.

  9. The Effect of Conceptual Advancement in Jazz Music Selections and Jazz Experience on Musicians' Aesthetic Response

    ERIC Educational Resources Information Center

    Coggiola, John C.

    2004-01-01

    This study is an investigation of what musicians consider to be their aesthetic experience with jazz music selections that vary in level of conceptual advancement (melodic complexity during improvised solos). Music major participants (N = 128) were assigned to either the jazz musician (n = 64) or nonjazz musician (n = 64) group. Data were gathered…

  10. Towards a Model of Technology Adoption: A Conceptual Model Proposition

    NASA Astrophysics Data System (ADS)

    Costello, Pat; Moreton, Rob

    A conceptual model for Information Communication Technology (ICT) adoption by Small Medium Enterprises (SMEs) is proposed. The research uses several ICT adoption models as its basis with theoretical underpinning provided by the Diffusion of Innovation theory and the Technology Acceptance Model (TAM). Taking an exploratory research approach the model was investigated amongst 200 SMEs whose core business is ICT. Evidence from this study demonstrates that these SMEs face the same issues as all other industry sectors. This work points out weaknesses in SMEs environments regarding ICT adoption and suggests what they may need to do to increase the success rate of any proposed adoption. The methodology for development of the framework is described and recommendations made for improved Government-led ICT adoption initiatives. Application of the general methodology has resulted in new opportunities to embed the ethos and culture surrounding the issues into the framework of new projects developed as a result of Government intervention. A conceptual model is proposed that may lead to a deeper understanding of the issues under consideration.

  11. Southern marl prairies conceptual ecological model

    USGS Publications Warehouse

    Davis, S.M.; Loftus, W.F.; Gaiser, E.E.; Huffman, A.E.

    2005-01-01

    About 190,000 ha of higher-elevation marl prairies flank either side of Shark River Slough in the southern Everglades. Water levels typically drop below the ground surface each year in this landscape. Consequently, peat soil accretion is inhibited, and substrates consist either of calcitic marl produced by algal periphyton mats or exposed limestone bedrock. The southern marl prairies support complex mosaics of wet prairie, sawgrass sawgrass (Cladium jamaicense), tree islands, and tropical hammock communities and a high diversity of plant species. However, relatively short hydroperiods and annual dry downs provide stressful conditions for aquatic fauna, affecting survival in the dry season when surface water is absent. Here, we present a conceptual ecological model developed for this landscape through scientific concensus, use of empirical data, and modeling. The two major societal drivers affecting the southern marl prairies are water management practices and agricultural and urban development. These drivers lead to five groups of ecosystem stressors: loss of spatial extent and connectivity, shortened hydroperiod and increased drought severity, extended hydroperiod and drying pattern reversals, introduction and spread of non-native trees, and introduction and spread of non-native fishes. Major ecological attributes include periphyton mats, plant species diversity and community mosaic, Cape Sable seaside sparrow (Ammodramus maritimus mirabilis), marsh fishes and associated aquatic fauna prey base, American alligator (Alligator mississippiensis), and wading bird early dry season foraging. Water management and development are hypothesized to have a negative effect on the ecological attributes of the southern marl prairies in the following ways. Periphyton mats have decreased in cover in areas where hydroperiod has been significantly reduced and changed in community composition due to inverse responses to increased nutrient availability. Plant species diversity and

  12. A Conceptual Model of Career Development to Enhance Academic Motivation

    ERIC Educational Resources Information Center

    Collins, Nancy Creighton

    2010-01-01

    The purpose of this study was to develop, refine, and validate a conceptual model of career development to enhance the academic motivation of community college students. To achieve this end, a straw model was built from the theoretical and empirical research literature. The model was then refined and validated through three rounds of a Delphi…

  13. A Conceptual Model To Assist Educational Leaders Manage Change.

    ERIC Educational Resources Information Center

    Cochren, John R.

    This paper presents a conceptual model to help school leaders manage change effectively. The model was developed from a literature review of theory development and model construction. Specifically, the paper identifies the major components that inhibit organizational change, and synthesizes the most salient features of these components through a…

  14. Advancing complex explanatory conceptualizations of daily negative and positive affect: trigger and maintenance coping action patterns.

    PubMed

    Dunkley, David M; Ma, Denise; Lee, Ihno A; Preacher, Kristopher J; Zuroff, David C

    2014-01-01

    The present study addressed a fundamental gap between research and clinical work by advancing complex explanatory conceptualizations of coping action patterns that trigger and maintain daily negative affect and (low) positive affect. One hundred ninety-six community adults completed measures of perfectionism, and then 6 months later completed questionnaires at the end of the day for 14 consecutive days to provide simultaneous assessments of appraisals, coping, and affect across different stressful situations in everyday life. Multilevel structural equation modeling (MSEM) supported complex explanatory conceptualizations that demonstrated (a) disengagement trigger patterns consisting of several distinct appraisals (e.g., event stress) and coping strategies (e.g., avoidant coping) that commonly operate together across many different stressors when the typical individual experiences daily increases in negative affect and drops in positive affect; and (b) disengagement maintenance patterns composed of different appraisal and coping maintenance factors that, in combination, can explain why individuals with higher levels of self-critical perfectionism have persistent daily negative affect and low positive mood 6 months later. In parallel, engagement patterns (triggers and maintenance) composed of distinct appraisals (e.g., perceived social support) and coping strategies (e.g., problem-focused coping) were linked to compensatory experiences of daily positive affect. These findings demonstrate the promise of using daily diary methodologies and MSEM to promote a shared understanding between therapists and clients of trigger and maintenance coping action patterns that explain what precipitates and perpetuates clients' difficulties, which, in turn, can help achieve the 2 overarching therapy goals of reducing clients' distress and bolstering resilience.

  15. Advancing complex explanatory conceptualizations of daily negative and positive affect: trigger and maintenance coping action patterns.

    PubMed

    Dunkley, David M; Ma, Denise; Lee, Ihno A; Preacher, Kristopher J; Zuroff, David C

    2014-01-01

    The present study addressed a fundamental gap between research and clinical work by advancing complex explanatory conceptualizations of coping action patterns that trigger and maintain daily negative affect and (low) positive affect. One hundred ninety-six community adults completed measures of perfectionism, and then 6 months later completed questionnaires at the end of the day for 14 consecutive days to provide simultaneous assessments of appraisals, coping, and affect across different stressful situations in everyday life. Multilevel structural equation modeling (MSEM) supported complex explanatory conceptualizations that demonstrated (a) disengagement trigger patterns consisting of several distinct appraisals (e.g., event stress) and coping strategies (e.g., avoidant coping) that commonly operate together across many different stressors when the typical individual experiences daily increases in negative affect and drops in positive affect; and (b) disengagement maintenance patterns composed of different appraisal and coping maintenance factors that, in combination, can explain why individuals with higher levels of self-critical perfectionism have persistent daily negative affect and low positive mood 6 months later. In parallel, engagement patterns (triggers and maintenance) composed of distinct appraisals (e.g., perceived social support) and coping strategies (e.g., problem-focused coping) were linked to compensatory experiences of daily positive affect. These findings demonstrate the promise of using daily diary methodologies and MSEM to promote a shared understanding between therapists and clients of trigger and maintenance coping action patterns that explain what precipitates and perpetuates clients' difficulties, which, in turn, can help achieve the 2 overarching therapy goals of reducing clients' distress and bolstering resilience. PMID:24447060

  16. A conceptual model for determining career choice of CHROME alumna based on farmer's conceptual models

    NASA Astrophysics Data System (ADS)

    Moore, Lisa Simmons

    This qualitative program evaluation examines the career decision-making processes and career choices of nine, African American women who participated in the Cooperating Hampton Roads Organization for Minorities in Engineering (CHROME) and who graduated from urban, rural or suburban high schools in the year 2000. The CHROME program is a nonprofit, pre-college intervention program that encourages underrepresented minority and female students to enter science, technically related, engineering, and math (STEM) career fields. The study describes career choices and decisions made by each participant over a five-year period since high school graduation. Data was collected through an Annual Report, Post High School Questionnaires, Environmental Support Questionnaires, Career Choice Questionnaires, Senior Reports, and standardized open-ended interviews. Data was analyzed using a model based on Helen C. Farmer's Conceptual Models, John Ogbu's Caste Theory and Feminist Theory. The CHROME program, based on its stated goals and tenets, was also analyzed against study findings. Findings indicated that participants received very low levels of support from counselors and teachers to pursue STEM careers and high levels of support from parents and family, the CHROME program and financial backing. Findings of this study also indicated that the majority of CHROME alumna persisted in STEM careers. The most successful participants, in terms of undergraduate degree completion and occupational prestige, were the African American women who remained single, experienced no critical incidents, came from a middle class to upper middle class socioeconomic background, and did not have children.

  17. A conceptual design of PRISM-2 for Advanced Land Observing Satellite-3(ALOS-3)

    NASA Astrophysics Data System (ADS)

    Imai, Hiroko; Katayama, Haruyoshi; Sagisaka, Masakazu; Hatooka, Yasushi; Suzuki, Shinichi; Osawa, Yuji; Takahashi, Masuo; Tadono, Takeo

    2012-09-01

    The Japan Aerospace Exploration Agency (JAXA) is planning a satellite system including Advanced Land Observing Satellites 2 and 3 (ALOS-2 and ALOS-3) for the ALOS follow-on program. ALOS-3 will carry the optical sensor named "PRISM-2" and extend the capabilities of earlier ALOS missions. PRISM-2 will be able to collect high-resolution (0.8m) and wide-swath (50 km) imagery with high geo-location accuracy, as well as provide precise digital surface models (DSMs) using stereo pair images acquired by two telescopes. These capabilities are ideal for obtaining large-scale geographical information such as elevation and land cover-maps for use in many research areas and practical applications, including disaster management support. JAXA has conducted a phase A study of the ALOS-3 spacecraft and PRISM-2, and is now working on prototype models of key components of PRISM-2's telescope, focal plane, and data compressor. This paper introduces a conceptual design for PRISM-2 and the ALOS-3 system.

  18. Guide for developing conceptual models for ecological risk assessments

    SciTech Connect

    Suter, G.W., II

    1996-05-01

    Ecological conceptual models are the result of the problem formulation phase of an ecological risk assessment, which is an important component of the Remedial Investigation process. They present hypotheses of how the site contaminants might affect the site ecology. The contaminant sources, routes, media, routes, and endpoint receptors are presented in the form of a flow chart. This guide is for preparing the conceptual models; use of this guide will standardize the models so that they will be of high quality, useful to the assessment process, and sufficiently consistent so that connections between sources of exposure and receptors can be extended across operable units (OU). Generic conceptual models are presented for source, aquatic integrator, groundwater integrator, and terrestrial OUs.

  19. Conceptual model for transferring information between small watersheds

    USGS Publications Warehouse

    Cleaves, E.T.

    2003-01-01

    Stream and watershed management and restoration can be greatly facilitated through use of physiographic landform classification to organize and communicate natural resource, hazard, and environmental information at a broad scale (1:250,000) as illustrated by the Piedmont and Coastal Plain Provinces in Maryland, or at a small scale (1:24,000) as illustrated using divisions and zones combined with a conceptual model. The conceptual model brings together geology, surficial processes, landforms and land use change information at the small watershed scale and facilitates transfer of information from one small watershed to another with similar geology and landforms. Stream flow, sediment erosion, and water quality illustrate the use of the model.

  20. Supporting user-defined granularities in a spatiotemporal conceptual model

    USGS Publications Warehouse

    Khatri, V.; Ram, S.; Snodgrass, R.T.; O'Brien, G. M.

    2002-01-01

    Granularities are integral to spatial and temporal data. A large number of applications require storage of facts along with their temporal and spatial context, which needs to be expressed in terms of appropriate granularities. For many real-world applications, a single granularity in the database is insufficient. In order to support any type of spatial or temporal reasoning, the semantics related to granularities needs to be embedded in the database. Specifying granularities related to facts is an important part of conceptual database design because under-specifying the granularity can restrict an application, affect the relative ordering of events and impact the topological relationships. Closely related to granularities is indeterminacy, i.e., an occurrence time or location associated with a fact that is not known exactly. In this paper, we present an ontology for spatial granularities that is a natural analog of temporal granularities. We propose an upward-compatible, annotation-based spatiotemporal conceptual model that can comprehensively capture the semantics related to spatial and temporal granularities, and indeterminacy without requiring new spatiotemporal constructs. We specify the formal semantics of this spatiotemporal conceptual model via translation to a conventional conceptual model. To underscore the practical focus of our approach, we describe an on-going case study. We apply our approach to a hydrogeologic application at the United States Geologic Survey and demonstrate that our proposed granularity-based spatiotemporal conceptual model is straightforward to use and is comprehensive.

  1. A Conceptual Model of Multiple Dimensions of Identity.

    ERIC Educational Resources Information Center

    Jones, Susan R.; McEwen, Marylu K.

    2000-01-01

    Presents a conceptual model of multiple dimensions of identity, which depicts a core sense of self or one's personal identity. Intersecting circles surrounding the core identity represent significant identity dimensions and contextual influences. The model evolved from a grounded theory study of a group of 10 women college students ranging in age…

  2. A Conceptual Model for Episodes of Acute, Unscheduled Care.

    PubMed

    Pines, Jesse M; Lotrecchiano, Gaetano R; Zocchi, Mark S; Lazar, Danielle; Leedekerken, Jacob B; Margolis, Gregg S; Carr, Brendan G

    2016-10-01

    We engaged in a 1-year process to develop a conceptual model representing an episode of acute, unscheduled care. Acute, unscheduled care includes acute illnesses (eg, nausea and vomiting), injuries, or exacerbations of chronic conditions (eg, worsening dyspnea in congestive heart failure) and is delivered in emergency departments, urgent care centers, and physicians' offices, as well as through telemedicine. We began with a literature search to define an acute episode of care and to identify existing conceptual models used in health care. In accordance with this information, we then drafted a preliminary conceptual model and collected stakeholder feedback, using online focus groups and concept mapping. Two technical expert panels reviewed the draft model, examined the stakeholder feedback, and discussed ways the model could be improved. After integrating the experts' comments, we solicited public comment on the model and made final revisions. The final conceptual model includes social and individual determinants of health that influence the incidence of acute illness and injury, factors that affect care-seeking decisions, specific delivery settings where acute care is provided, and outcomes and costs associated with the acute care system. We end with recommendations for how researchers, policymakers, payers, patients, and providers can use the model to identify and prioritize ways to improve acute care delivery. PMID:27397857

  3. Revisiting "Discrepancy Analysis in Continuing Medical Education: A Conceptual Model"

    ERIC Educational Resources Information Center

    Fox, Robert D.

    2011-01-01

    Based upon a review and analysis of selected literature, the author presents a conceptual model of discrepancy analysis evaluation for planning, implementing, and assessing the impact of continuing medical education (CME). The model is described in terms of its value as a means of diagnosing errors in the development and implementation of CME. The…

  4. Discrepancy Analysis in Continuing Medical Education: A Conceptual Model.

    ERIC Educational Resources Information Center

    Fox, Robert D.

    1983-01-01

    Presents a conceptual model of discrepancy analysis evaluation for planning, evaluating, and assessing the impact of continuing medical education (CME). Describes the model in terms of its value as a means of diagnosing errors in the development and implementation of CME. (JOW)

  5. Newman Unit 1 advanced solar repowering advanced conceptual design. Final report

    SciTech Connect

    1982-04-01

    The Newman Unit 1 solar repowering design is a water/steam central receiver concept supplying superheated steam. The work reported is to develop a refined baseline conceptual design that has potential for construction and operation by 1986, makes use of existing solar thermal technology, and provides the best economics for this application. Trade studies performed in the design effort are described, both for the conceptual design of the overall system and for the subsystem conceptual design. System-level functional requirements, design, operation, performance, cost, safety, environmental, institutional, and regulatory considerations are described. Subsystems described include the collector, receiver, fossil energy, electrical power generating, and master control subsystems, site and site facilities. The conceptual design, cost, and performance of each subsystem is discussed at length. A detailed economic analysis of the repowered unit is made to realistically assess the economics of the first repowered unit using present cost data for a limited production level for solar hardware. Finally, a development plan is given, including the design, procurement, construction, checkout, startup, performance validation, and commercial operation. (LEW)

  6. Conceptual astronomy: A novel model for teaching postsecondary science courses

    NASA Astrophysics Data System (ADS)

    Zeilik, Michael; Schau, Candace; Mattern, Nancy; Hall, Shannon; Teague, Kathleen W.; Bisard, Walter

    1997-10-01

    An innovative, conceptually based instructional model for teaching large undergraduate astronomy courses was designed, implemented, and evaluated in the Fall 1995 semester. This model was based on cognitive and educational theories of knowledge and, we believe, is applicable to other large postsecondary science courses. Major components were: (a) identification of the basic important concepts and their interrelationships that are necessary for connected understanding of astronomy in novice students; (b) use of these concepts and their interrelationships throughout the design, implementation, and evaluation stages of the model; (c) identification of students' prior knowledge and misconceptions; and (d) implementation of varied instructional strategies targeted toward encouraging conceptual understanding in students (i.e., instructional concept maps, cooperative small group work, homework assignments stressing concept application, and a conceptually based student assessment system). Evaluation included the development and use of three measures of conceptual understanding and one of attitudes toward studying astronomy. Over the semester, students showed very large increases in their understanding as assessed by a conceptually based multiple-choice measure of misconceptions, a select-and-fill-in concept map measure, and a relatedness-ratings measure. Attitudes, which were slightly positive before the course, changed slightly in a less favorable direction.

  7. C-130 Advanced Technology Center wing box conceptual design/cost study

    NASA Technical Reports Server (NTRS)

    Whitehead, R. S.; Foreman, C. R.; Silva, K.

    1992-01-01

    A conceptual design was developed by Northrop/LTV for an advanced C-130 Center Wing Box (CWB) which could meet the severe mission requirements of the SOF C-130 aircraft. The goals for the advanced technology CWB relative to the current C-130H CWB were: (1) the same acquisition cost; (2) lower operating support costs; (3) equal or lower weight; (4) a 30,000 hour service life for the SOF mission; and (5) minimum impact on the current maintenance concept. Initially, the structural arrangement, weight, external and internal loads, fatigue spectrum, flutter envelope and design criteria for the SOF C-130 aircraft CWB were developed. An advanced materials assessment was then conducted to determine the suitability of advanced materials for a 1994 production availability and detailed trade studies were performed on candidate CWB conceptual designs. Finally, a life-cycle cost analysis was performed on the advanced CWB. The study results showed that a hybrid composite/metallic CWB could meet the severe SOF design requirements, reduce the CWB weight by 14 pct., and was cost effective relative to an all metal beefed up C-130H CWB.

  8. Advanced Chemistry Basins Model

    SciTech Connect

    William Goddard; Mario Blanco; Lawrence Cathles; Paul Manhardt; Peter Meulbroek; Yongchun Tang

    2002-11-10

    The DOE-funded Advanced Chemistry Basin model project is intended to develop a public domain, user-friendly basin modeling software under PC or low end workstation environment that predicts hydrocarbon generation, expulsion, migration and chemistry. The main features of the software are that it will: (1) afford users the most flexible way to choose or enter kinetic parameters for different maturity indicators; (2) afford users the most flexible way to choose or enter compositional kinetic parameters to predict hydrocarbon composition (e.g., gas/oil ratio (GOR), wax content, API gravity, etc.) at different kerogen maturities; (3) calculate the chemistry, fluxes and physical properties of all hydrocarbon phases (gas, liquid and solid) along the primary and secondary migration pathways of the basin and predict the location and intensity of phase fractionation, mixing, gas washing, etc.; and (4) predict the location and intensity of de-asphaltene processes. The project has be operative for 36 months, and is on schedule for a successful completion at the end of FY 2003.

  9. Conceptual definition of a technology development mission for advanced solar dynamic power systems

    NASA Technical Reports Server (NTRS)

    Migra, R. P.

    1986-01-01

    An initial conceptual definition of a technology development mission for advanced solar dynamic power systems is provided, utilizing a space station to provide a dedicated test facility. The advanced power systems considered included Brayton, Stirling, and liquid metal Rankine systems operating in the temperature range of 1040 to 1400 K. The critical technologies for advanced systems were identified by reviewing the current state of the art of solar dynamic power systems. The experimental requirements were determined by planning a system test of a 20 kWe solar dynamic power system on the space station test facility. These requirements were documented via the Mission Requirements Working Group (MRWG) and Technology Development Advocacy Group (TDAG) forms. Various concepts or considerations of advanced concepts are discussed. A preliminary evolutionary plan for this technology development mission was prepared.

  10. A Conceptual Model for Leadership Transition

    ERIC Educational Resources Information Center

    Manderscheid, Steven V.; Ardichvili, Alexandre

    2008-01-01

    The purpose of this study was to develop a model of leadership transition based on an integrative review of literature. The article establishes a compelling case for focusing on leadership transitions as an area for study and leadership development practitioner intervention. The proposed model in this study identifies important success factors…

  11. A Conceptual Model for Effective Distance Learning in Higher Education

    ERIC Educational Resources Information Center

    Farajollahi, Mehran; Zare, Hosein; Hormozi, Mahmood; Sarmadi, Mohammad Reza; Zarifsanaee, Nahid

    2010-01-01

    The present research aims at presenting a conceptual model for effective distance learning in higher education. Findings of this research shows that an understanding of the technological capabilities and learning theories especially constructive theory and independent learning theory and communicative and interaction theory in Distance learning is…

  12. A Conceptual Model of the World of Work.

    ERIC Educational Resources Information Center

    VanRooy, William H.

    The conceptual model described in this paper resulted from the need to organize a body of knowledge related to the world of work which would enable curriculum developers to prepare accurate, realistic instructional materials. The world of work is described by applying Malinowski's scientific study of the structural components of culture. It is…

  13. Designing Public Library Websites for Teens: A Conceptual Model

    ERIC Educational Resources Information Center

    Naughton, Robin Amanda

    2012-01-01

    The main goal of this research study was to develop a conceptual model for the design of public library websites for teens (TLWs) that would enable designers and librarians to create library websites that better suit teens' information needs and practices. It bridges a gap in the research literature between user interface design in…

  14. Conceptualizations of Creativity: Comparing Theories and Models of Giftedness

    ERIC Educational Resources Information Center

    Miller, Angie L.

    2012-01-01

    This article reviews seven different theories of giftedness that include creativity as a component, comparing and contrasting how each one conceptualizes creativity as a part of giftedness. The functions of creativity vary across the models, suggesting that while the field of gifted education often cites the importance of creativity, the…

  15. A Multiperspectival Conceptual Model of Transformative Meaning Making

    ERIC Educational Resources Information Center

    Freed, Maxine

    2009-01-01

    Meaning making is central to transformative learning, but little work has explored how meaning is constructed in the process. Moreover, no meaning-making theory adequately captures its characteristics and operations during radical transformation. The purpose of this dissertation was to formulate and specify a multiperspectival conceptual model of…

  16. Mapping the Territory: A Conceptual Model of Scholastic Journalism.

    ERIC Educational Resources Information Center

    Arnold, Mary

    1991-01-01

    Describes scholastic journalism as the teaching of secondary school students to gather, process, and present information to an audience. Offers a model focusing upon scholastic journalism's conceptual areas of law and ethics, history and cultural diversity, technology and financial support, media and content, pedagogy, and working context as a…

  17. Developing a Conceptual Model for Career Support for New Academics

    ERIC Educational Resources Information Center

    Adcroft, Andy

    2010-01-01

    The aim of this paper is to develop a conceptual model which allows for an understanding of the general and discipline specific support needed by academics new to the profession. The approach taken is qualitative in nature and centers around a series of semi-structured interviews carried out with new academics and senior managers in two…

  18. The SCRAPE Model; A Conceptual Approach to Educational Program Evaluation.

    ERIC Educational Resources Information Center

    Liberty, Paul G., Jr.

    Using effectivemess, efficiency, self-sustenance, and communicability as criteria, a conceptual model, called SCRAPE, was developed at the University of Texas to systematically describe educational behaviors. The key elements of the system are: (1) diagnosis and prescription, (2) instructional events, (3) achievement evaluation, and (4) consequent…

  19. Sources of Sex Discrimination in Educational Systems: A Conceptual Model

    ERIC Educational Resources Information Center

    Kutner, Nancy G.; Brogan, Donna

    1976-01-01

    A conceptual model is presented relating numerous variables contributing to sexism in American education. Discrimination is viewed as intervening between two sets of interrelated independent variables and the dependent variable of sex inequalities in educational attainment. Sex-role orientation changes are the key to significant change in the…

  20. A new conceptual model of convection

    SciTech Connect

    Walcek, C.

    1995-09-01

    Classical cumulus parameterizations assume that cumulus clouds are entraining plumes of hot air rising through the atmosphere. However, ample evidence shows that clouds cannot be simulated using this approach. Dr. Walcek suggests that cumulus clouds can be reasonably simulated by assuming that buoyant plumes detrain mass as they rise through the atmosphere. Walcek successfully simulates measurements of tropical convection using this detraining model of cumulus convection. Comparisons with measurements suggest that buoyant plumes encounter resistance to upward movement as they pass through dry layers in the atmosphere. This probably results from turbulent mixing and evaporation of cloud water, which generates negatively buoyant mixtures which detrain from the upward moving plume. This mass flux model of detraining plumes is considerably simpler than existing mass flux models, yet reproduces many of the measured effects associated with convective activity. 1 fig.

  1. Conceptualizing Evolving Models of Educational Development

    ERIC Educational Resources Information Center

    Fraser, Kym; Gosling, David; Sorcinelli, Mary Deane

    2010-01-01

    Educational development, which the authors use to refer to the field of professional and strategic development associated with university and college learning and teaching, can be described in many ways by referring to its different aspects. In this article the authors endeavor to categorize many of the models that have been used to describe…

  2. Conceptual model for assessment of dermal exposure

    PubMed Central

    Schneider, T.; Vermeulen, R.; Brouwer, D. H.; Cherrie, J. W.; Kromhout, H.; Fogh, C. L.

    1999-01-01

    Dermal exposure, primarily to pesticides, has been measured for almost half a century. Compared with exposure by inhalation, limited progress has been made towards standardisation of methods of measurement and development of biologically relevant exposure measures. It is suggested that the absence of a consistent terminology and a theoretical model has been an important cause of this lack of progress. Therefore, a consistent terminology based on a multicompartment model for assessment of dermal exposure is proposed that describes the transport of contaminant mass from the source of the hazardous substance to the surface of the skin. Six compartments and two barriers together with eight mass transport processes are described. With the model structure, examples are given of what some existing methods actually measure and where there are limited, or no, methods for measuring the relevant mass in a compartment or transport of mass. The importance of measuring the concentration of contaminant and not mass per area in the skin contaminant layer is stressed, as it is the concentration difference between the skin contamination layer and the perfused tissue that drives uptake. Methods for measuring uptake are currently not available. Measurement of mass, concentration, and the transport processes must be based on a theoretical model. Standardisation of methods of measurement of dermal exposure is strongly recommended.   PMID:10658563

  3. A conceptual model of morphogenesis and regeneration

    PubMed Central

    Tosenberger, A.; Bessonov, N.; Levin, M.; Reinberg, N.; Volpert, V.; Morozova, N.

    2016-01-01

    This paper is devoted to computer modelling of the development and regeneration of multicellular biological structures. Some species (e.g., planaria and salamanders) are able to regenerate parts of their body after amputation damage, but the global rules governing cooperative cell behaviour during morphogenesis are not known. Here, we consider a simplified model organism, which consists of tissues formed around special cells that can be interpreted as stem cells. We assume that stem cells communicate with each other by a set of signals, and that the values of these signals depend on the distance between cells. Thus the signal distribution characterizes location of stem cells. If the signal distribution is changed, then the difference between the initial and the current signal distribution affects the behaviour of stem cells – e.g. as a result of an amputation of a part of tissue the signal distribution changes which stimulates stem cells to migrate to new locations, appropriate for regeneration of the proper pattern. Moreover, as stem cells divide and form tissues around them, they control the form and the size of regenerating tissues. This two-level organization of the model organism, with global regulation of stem cells and local regulation of tissues, allows its reproducible development and regeneration. PMID:25822060

  4. Annex to 7-GeV Advanced Photon Source Conceptual Design Report

    SciTech Connect

    Not Available

    1988-05-01

    The Annex to the 7-GeV Advanced Photon Source Conceptual Design Report updates the Conceptual Design Report of 1987 (CDR-87) to include the results of further optimization and changes of the design during the past year. The design changes can be summarized as affecting three areas: the accelerator system, conventional facilities, and experimental systems. Most of the changes in the accelerator system result from inclusion of a positron accumulator ring (PAR), which was added at the suggestion of the 1987 DOE Review Committee, to speed up the filling rate of the storage ring. The addition of the PAR necessitates many minor changes in the linac system, the injector synchrotron, and the low-energy beam transport lines. 63 figs., 18 tabs.

  5. Conceptual Commitments of the LIDA Model of Cognition

    NASA Astrophysics Data System (ADS)

    Franklin, Stan; Strain, Steve; McCall, Ryan; Baars, Bernard

    2013-06-01

    Significant debate on fundamental issues remains in the subfields of cognitive science, including perception, memory, attention, action selection, learning, and others. Psychology, neuroscience, and artificial intelligence each contribute alternative and sometimes conflicting perspectives on the supervening problem of artificial general intelligence (AGI). Current efforts toward a broad-based, systems-level model of minds cannot await theoretical convergence in each of the relevant subfields. Such work therefore requires the formulation of tentative hypotheses, based on current knowledge, that serve to connect cognitive functions into a theoretical framework for the study of the mind. We term such hypotheses "conceptual commitments" and describe the hypotheses underlying one such model, the Learning Intelligent Distribution Agent (LIDA) Model. Our intention is to initiate a discussion among AGI researchers about which conceptual commitments are essential, or particularly useful, toward creating AGI agents.

  6. Performance potential of an advanced technology Mach 3 turbojet engine installed on a conceptual high-speed civil transport

    NASA Technical Reports Server (NTRS)

    Morris, Shelby J., Jr.; Geiselhart, Karl A.; Coen, Peter G.

    1989-01-01

    The performance of an advanced technology conceptual turbojet optimized for a high-speed civil aircraft is presented. This information represents an estimate of performance of a Mach 3 Brayton (gas turbine) cycle engine optimized for minimum fuel burned at supersonic cruise. This conceptual engine had no noise or environmental constraints imposed upon it. The purpose of this data is to define an upper boundary on the propulsion performance for a conceptual commercial Mach 3 transport design. A comparison is presented demonstrating the impact of the technology proposed for this conceptual engine on the weight and other characteristics of a proposed high-speed civil transport. This comparison indicates that the advanced technology turbojet described could reduce the gross weight of a hypothetical Mach 3 high-speed civil transport design from about 714,000 pounds to about 545,000 pounds. The aircraft with the baseline engine and the aircraft with the advanced technology engine are described.

  7. Advanced X-Ray Timing Array Mission: Conceptual Spacecraft Design Study

    NASA Technical Reports Server (NTRS)

    Hopkins, R. C.; Johnson, L.; Thomas, H. D.; Wilson-Hodge, C. A.; Baysinger, M.; Maples, C. D.; Fabisinski, L.L.; Hornsby, L.; Thompson, K. S.; Miernik, J. H.

    2011-01-01

    The Advanced X-Ray Timing Array (AXTAR) is a mission concept for submillisecond timing of bright galactic x-ray sources. The two science instruments are the Large Area Timing Array (LATA) (a collimated instrument with 2-50-keV coverage and over 3 square meters of effective area) and a Sky Monitor (SM), which acts as a trigger for pointed observations of x-ray transients. The spacecraft conceptual design team developed two spacecraft concepts that will enable the AXTAR mission: A minimal configuration to be launched on a Taurus II and a larger configuration to be launched on a Falcon 9 or similar vehicle.

  8. Comparison of Conceptual and Neural Network Rainfall-Runoff Models

    NASA Astrophysics Data System (ADS)

    Vidyarthi, V. K.; Jain, A.

    2014-12-01

    Rainfall-runoff (RR) model is a key component of any water resource application. There are two types of techniques usually employed for RR modeling: physics based and data-driven techniques. Although the physics based models have been used for operational purposes for a very long time, they provide only reasonable accuracy in modeling and forecasting. On the other hand, the Artificial Neural Networks (ANNs) have been reported to provide superior modeling performance; however, they have not been acceptable by practitioners, decision makers and water resources engineers as operational tools. The ANNs one of the data driven techniques, became popular for efficient modeling of the complex natural systems in the last couple of decades. In this paper, the comparative results for conceptual and ANN models in RR modeling are presented. The conceptual models were developed by the use of rainfall-runoff library (RRL) and genetic algorithm (GA) was used for calibration of these models. Feed-forward neural network model structure trained by Levenberg-Marquardt (LM) training algorithm has been adopted here to develop all the ANN models. The daily rainfall, runoff and various climatic data derived from Bird creek basin, Oklahoma, USA were employed to develop all the models included here. Daily potential evapotranspiration (PET), which was used in conceptual model development, was calculated by the use of Penman equation. The input variables were selected on the basis of correlation analysis. The performance evaluation statistics such as average absolute relative error (AARE), Pearson's correlation coefficient (R) and threshold statistics (TS) were used for assessing the performance of all the models developed here. The results obtained in this study show that the ANN models outperform the conventional conceptual models due to their ability to learn the non-linearity and complexity inherent in data of rainfall-runoff process in a more efficient manner. There is a strong need to

  9. Promoting Conceptual Coherence in Quantum Learning through Computational Models

    NASA Astrophysics Data System (ADS)

    Lee, Hee-Sun

    2012-02-01

    In order to explain phenomena at the quantum level, scientists use multiple representations in verbal, pictorial, mathematical, and computational forms. Conceptual coherence among these multiple representations is used as an analytical framework to describe student learning trajectories in quantum physics. A series of internet-based curriculum modules are designed to address topics in quantum mechanics, semiconductor physics, and nano-scale engineering applications. In these modules, students are engaged in inquiry-based activities situated in a highly interactive computational modeling environment. This study was conducted in an introductory level solid state physics course. Based on in-depth interviews with 13 students, methods for identifying conceptual coherence as a function of students' level of understanding are presented. Pre-post test comparisons of 20 students in the course indicate a statistically significant improvement in students' conceptual coherence of understanding quantum phenomena before and after the course, Effect Size = 1.29 SD. Additional analyses indicate that students who responded to the modules more coherently improved their conceptual coherence to a greater extent than those who did less to the modules after controlling for their course grades.

  10. Conceptual Model for Selenium Cycling in the Great Salt Lake

    NASA Astrophysics Data System (ADS)

    Johnson, W. P.; Conover, M. R.; Wurtsbaugh, W. A.; Adams, J.

    2006-12-01

    The conceptual model for Selenium cycling in the Great Salt Lake was developed to guide investigations in support of determining an open water selenium standard for the Great Salt Lake. The motivation to determine this particular selenium standard derives from public concern for a plan to allow disposal of reverse osmosis (RO) concentrate in the GSL, which would contain elevated concentrations of major and trace elements, including selenium. The development of an open water standard for selenium requires a working knowledge of the biological significance of existing selenium concentrations in the Great Salt Lake, as well as a working understanding of the likely changes of these concentrations over time given existing and proposed loads to the system. This working knowledge" is being represented in a conceptual model that accounts for selenium in various stocks" in the system (e.g. water, sediment, biota) and the flow" of selenium between stocks (e.g., precipitation and settling, volatilization, bioconcentration). It illustrates the critical pathway of selenium in the Great Salt Lake from water, to microorganisms, to brine shrimp and brine flies, to birds, and to their eggs. It also addresses the complexity of the GSL system: a) Spatially diverse, being comprised by four distinct bays and two layers, with major differences in salinity among their waters. b) Temporally dynamic, due to seasonal and inter-annual variations in runoff. The conceptual model is presently descriptive, but will serve as the basis for a semi-quantitative model that will be fed by data accumulated during subsequent investigations.

  11. eLac - Conceptual Model for Flood Management

    NASA Astrophysics Data System (ADS)

    Rata, Marius; Florentin Draghia, Aurelian; Drobot, Radu; Matreata, Marius; Corbus, Ciprian

    2015-04-01

    This article reviews the conceptual model of the decision support system (DSS) for flood management activities introduced in the scope of e-LAC project. Following the general system architecture which has an emphasize on the water management decision processes, hydrologic and hydraulic models are introduced and discussed according to their specific DSS integration potential. Three directions are discussed in dedicated sections corresponding to the main modules defined in the conceptual model : the Water Basin Management Module (mainly implements the management decision flow, but manages also data exchange between hydrologic modeling module and hydraulic modeling module, allow real time visualization for hydrological data), the Hydrologic Modeling Module (manages all the modeling functionalities of rainfalls - runoff processes, providing continuous hydrologic forecasts with a variable time-step depending on the actual basin situation) and the Hydraulic Modeling Module (computes the flood's waves routing having as boundary upstream conditions the discharge hydrographs, generated both by catchment's upper area, river tributaries and inter-basins, respectively the rating curves, water level hydrograph or water surface slope as downstream condition). The GIS concepts are contextually reviewed based on their use as geospatial database for water management modeling, integration within hydrologic time courses, hydraulic modeling (from both software and management perspective), expert knowledge or mathematical modeling results (knowledge database, rules).

  12. Scientific and conceptual flaws of coercive treatment models in addiction.

    PubMed

    Uusitalo, Susanne; van der Eijk, Yvette

    2016-01-01

    In conceptual debates on addiction, neurobiological research has been used to support the idea that addicted drug users lack control over their addiction-related actions. In some interpretations, this has led to coercive treatment models, in which, the purpose is to 'restore' control. However, neurobiological studies that go beyond what is typically presented in conceptual debates paint a different story. In particular, they indicate that though addiction has neurobiological manifestations that make the addictive behaviour difficult to control, it is possible for individuals to reverse these manifestations through their own efforts. Thus, addicted individuals should not be considered incapable of making choices voluntarily, simply on the basis that addiction has neurobiological manifestations, and coercive treatment models of addiction should be reconsidered in this respect.

  13. CONCEPTUAL MODELS AND METHODS TO GUIDE DIAGNOSTIC RESEARCH INTO CAUSES OF IMPAIRMENT TO AQUATIC ECOSYSTEMS

    EPA Science Inventory

    Methods and conceptual models to guide the development of tools for diagnosing the causes of biological impairment within aquatic ecosystems of the United States are described in this report. The conceptual models developed here address nutrients, suspended and bedded sediments (...

  14. Advanced turbine systems program conceptual design and product development. Annual report, August 1994--July 1995

    SciTech Connect

    1995-11-01

    This report summarizes the tasks completed under this project during the period from August 1, 1994 through July 31, 1994. The objective of the study is to provide the conceptual design and product development plan for an ultra high efficiency, environmentally superior and cost-competitive industrial gas turbine system to be commercialized by the year 2000. The tasks completed include a market study for the advanced turbine system; definition of an optimized recuperated gas turbine as the prime mover meeting the requirements of the market study and whose characteristics were, in turn, used for forecasting the total advanced turbine system (ATS) future demand; development of a program plan for bringing the ATS to a state of readiness for field test; and demonstration of the primary surface recuperator ability to provide the high thermal effectiveness and low pressure loss required to support the proposed ATS cycle.

  15. Task 6 -- Advanced turbine systems program conceptual design and product development

    SciTech Connect

    1996-01-10

    The Allison Engine Company has completed the Task 6 Conceptual Design and Analysis of Phase 2 of the Advanced Turbine System (ATS) contract. At the heart of Allison`s system is an advanced simple cycle gas turbine engine. This engine will incorporate components that ensure the program goals are met. Allison plans to commercialize the ATS demonstrator and market a family of engines incorporating this technology. This family of engines, ranging from 4.9 MW to 12 MW, will be suitable for use in all industrial engine applications, including electric power generation, mechanical drive, and marine propulsion. In the field of electric power generation, the engines will be used for base load, standby, cogeneration, and distributed generation applications.

  16. HESS Opinions "Topography driven conceptual modelling (FLEX-Topo)"

    NASA Astrophysics Data System (ADS)

    Savenije, H. H. G.

    2010-07-01

    Heterogeneity and complexity of hydrological processes offer substantial challenges to the hydrological modeller. Some hydrologists try to tackle this problem by introducing more and more detail in their models, or by setting-up more and more complicated models starting from basic principles at the smallest possible level. As we know, this reductionist approach leads to ever higher levels of equifinality and predictive uncertainty. On the other hand, simple, lumped and parsimonious models may be too simple to be realistic or representative of the dominant hydrological processes. In this commentary, a new model approach is proposed that tries to find the middle way between complex distributed and simple lumped modelling approaches. Here we try to find the right level of simplification while avoiding over-simplification. Paraphrasing Einstein, the maxim is: make a model as simple as possible, but not simpler than that. The approach presented is process based, but not physically based in the traditional sense. Instead, it is based on a conceptual representation of the dominant physical processes in certain key elements of the landscape. The essence of the approach is that the model structure is made dependent on a limited number of landscape classes in which the topography is the main driver, but which can include geological, geomorphological or land-use classification. These classes are then represented by lumped conceptual models that act in parallel. The advantage of this approach over a fully distributed conceptualisation is that it retains maximum simplicity while taking into account observable landscape characteristics.

  17. Conceptual Models in Health Informatics Research: A Literature Review and Suggestions for Development

    PubMed Central

    2016-01-01

    Background Contributing to health informatics research means using conceptual models that are integrative and explain the research in terms of the two broad domains of health science and information science. However, it can be hard for novice health informatics researchers to find exemplars and guidelines in working with integrative conceptual models. Objectives The aim of this paper is to support the use of integrative conceptual models in research on information and communication technologies in the health sector, and to encourage discussion of these conceptual models in scholarly forums. Methods A two-part method was used to summarize and structure ideas about how to work effectively with conceptual models in health informatics research that included (1) a selective review and summary of the literature of conceptual models; and (2) the construction of a step-by-step approach to developing a conceptual model. Results The seven-step methodology for developing conceptual models in health informatics research explained in this paper involves (1) acknowledging the limitations of health science and information science conceptual models; (2) giving a rationale for one’s choice of integrative conceptual model; (3) explicating a conceptual model verbally and graphically; (4) seeking feedback about the conceptual model from stakeholders in both the health science and information science domains; (5) aligning a conceptual model with an appropriate research plan; (6) adapting a conceptual model in response to new knowledge over time; and (7) disseminating conceptual models in scholarly and scientific forums. Conclusions Making explicit the conceptual model that underpins a health informatics research project can contribute to increasing the number of well-formed and strongly grounded health informatics research projects. This explication has distinct benefits for researchers in training, research teams, and researchers and practitioners in information, health, and other

  18. IMM: a multisystem memory model for conceptual learning.

    PubMed

    Saleh, Mai Sabry

    2014-01-01

    Concepts of learning and memory are closely related, and the terms often describe the same processes. Conceptual learning is known to be the process of developing abstract rules or mental constructs based on sensory experience. The Integrated Model of Mind (IMM), introduced in the present work, is a theoretical multisystem memory model that describes how concepts are formed. The IMM in its design arranges memory systems after their function in an integrated and harmonized sequence. It provides answers to some limitations of Tulving's serial-parallel-independent (SPI) model and suggests a new assumption with respect to mental representation and image schema construction through the process of encoding.

  19. Conceptual Model of Quantities, Units, Dimensions, and Values

    NASA Technical Reports Server (NTRS)

    Rouquette, Nicolas F.; DeKoenig, Hans-Peter; Burkhart, Roger; Espinoza, Huascar

    2011-01-01

    JPL collaborated with experts from industry and other organizations to develop a conceptual model of quantities, units, dimensions, and values based on the current work of the ISO 80000 committee revising the International System of Units & Quantities based on the International Vocabulary of Metrology (VIM). By providing support for ISO 80000 in SysML via the International Vocabulary of Metrology (VIM), this conceptual model provides, for the first time, a standard-based approach for addressing issues of unit coherence and dimensional analysis into the practice of systems engineering with SysML-based tools. This conceptual model provides support for two kinds of analyses specified in the International Vocabulary of Metrology (VIM): coherence of units as well as of systems of units, and dimension analysis of systems of quantities. To provide a solid and stable foundation, the model for defining quantities, units, dimensions, and values in SysML is explicitly based on the concepts defined in VIM. At the same time, the model library is designed in such a way that extensions to the ISQ (International System of Quantities) and SI Units (Systeme International d Unites) can be represented, as well as any alternative systems of quantities and units. The model library can be used to support SysML user models in various ways. A simple approach is to define and document libraries of reusable systems of units and quantities for reuse across multiple projects, and to link units and quantity kinds from these libraries to Unit and QuantityKind stereotypes defined in SysML user models.

  20. Life cycle cost modeling of conceptual space vehicles

    NASA Technical Reports Server (NTRS)

    Ebeling, Charles

    1993-01-01

    This paper documents progress to date by the University of Dayton on the development of a life cycle cost model for use during the conceptual design of new launch vehicles and spacecraft. This research is being conducted under NASA Research Grant NAG-1-1327. This research effort changes the focus from that of the first two years in which a reliability and maintainability model was developed to the initial development of a life cycle cost model. Cost categories are initially patterned after NASA's three axis work breakdown structure consisting of a configuration axis (vehicle), a function axis, and a cost axis. The focus will be on operations and maintenance costs and other recurring costs. Secondary tasks performed concurrent with the development of the life cycle costing model include continual support and upgrade of the R&M model. The primary result of the completed research will be a methodology and a computer implementation of the methodology to provide for timely cost analysis in support of the conceptual design activities. The major objectives of this research are: to obtain and to develop improved methods for estimating manpower, spares, software and hardware costs, facilities costs, and other cost categories as identified by NASA personnel; to construct a life cycle cost model of a space transportation system for budget exercises and performance-cost trade-off analysis during the conceptual and development stages; to continue to support modifications and enhancements to the R&M model; and to continue to assist in the development of a simulation model to provide an integrated view of the operations and support of the proposed system.

  1. Advanced Usage of Vehicle Sketch Pad for CFD-Based Conceptual Design

    NASA Technical Reports Server (NTRS)

    Ordaz, Irian; Li, Wu

    2013-01-01

    Conceptual design is the most fluid phase of aircraft design. It is important to be able to perform large scale design space exploration of candidate concepts that can achieve the design intent to avoid more costly configuration changes in later stages of design. This also means that conceptual design is highly dependent on the disciplinary analysis tools to capture the underlying physics accurately. The required level of analysis fidelity can vary greatly depending on the application. Vehicle Sketch Pad (VSP) allows the designer to easily construct aircraft concepts and make changes as the design matures. More recent development efforts have enabled VSP to bridge the gap to high-fidelity analysis disciplines such as computational fluid dynamics and structural modeling for finite element analysis. This paper focuses on the current state-of-the-art geometry modeling for the automated process of analysis and design of low-boom supersonic concepts using VSP and several capability-enhancing design tools.

  2. Integrating O/S models during conceptual design, part 1

    NASA Technical Reports Server (NTRS)

    Ebeling, Charles E.

    1994-01-01

    The University of Dayton is pleased to submit this report to the National Aeronautics and Space Administration (NASA), Langley Research Center, which integrates a set of models for determining operational capabilities and support requirements during the conceptual design of proposed space systems. This research provides for the integration of the reliability and maintainability (R&M) model, both new and existing simulation models, and existing operations and support (O&S) costing equations in arriving at a complete analysis methodology. Details concerning the R&M model and the O&S costing model may be found in previous reports accomplished under this grant (NASA Research Grant NAG1-1327). In the process of developing this comprehensive analysis approach, significant enhancements were made to the R&M model, updates to the O&S costing model were accomplished, and a new simulation model developed. This is the 1st part of a 3 part technical report.

  3. Misrepresentation and amendment of soil moisture in conceptual hydrological modelling

    NASA Astrophysics Data System (ADS)

    Zhuo, Lu; Han, Dawei

    2016-04-01

    Although many conceptual models are very effective in simulating river runoff, their soil moisture schemes are generally not realistic in comparison with the reality (i.e., getting the right answers for the wrong reasons). This study reveals two significant misrepresentations in those models through a case study using the Xinanjiang model which is representative of many well-known conceptual hydrological models. The first is the setting of the upper limit of its soil moisture at the field capacity, due to the 'holding excess runoff' concept (i.e., runoff begins on repletion of its storage to the field capacity). The second is neglect of capillary rise of water movement. A new scheme is therefore proposed to overcome those two issues. The amended model is as effective as its original form in flow modelling, but represents more logically realistic soil water processes. The purpose of the study is to enable the hydrological model to get the right answers for the right reasons. Therefore, the new model structure has a better capability in potentially assimilating soil moisture observations to enhance its real-time flood forecasting accuracy. The new scheme is evaluated in the Pontiac catchment of the USA through a comparison with satellite observed soil moisture. The correlation between the XAJ and the observed soil moisture is enhanced significantly from 0.64 to 0.70. In addition, a new soil moisture term called SMDS (Soil Moisture Deficit to Saturation) is proposed to complement the conventional SMD (Soil Moisture Deficit).

  4. HESS Opinions "Topography driven conceptual modelling (FLEX-Topo)"

    NASA Astrophysics Data System (ADS)

    Savenije, H. H. G.

    2010-12-01

    Heterogeneity and complexity of hydrological processes offer substantial challenges to the hydrological modeller. Some hydrologists try to tackle this problem by introducing more and more detail in their models, or by setting-up more and more complicated models starting from basic principles at the smallest possible level. As we know, this reductionist approach leads to ever higher levels of equifinality and predictive uncertainty. On the other hand, simple, lumped and parsimonious models may be too simple to be realistic or representative of the dominant hydrological processes. In this commentary, a new approach is proposed that tries to find the middle way between complex distributed and simple lumped modelling approaches. Here we try to find the right level of simplification while avoiding over-simplification. Paraphrasing Einstein, the maxim is: make a model as simple as possible, but not simpler than that. The approach presented is process based, but not physically based in the traditional sense. Instead, it is based on a conceptual representation of the dominant physical processes in certain key elements of the landscape. The essence of the approach is that the model structure is made dependent on a limited number of landscape classes in which the topography is the main driver, but which can include geological, geomorphological or land-use classification. These classes are then represented by lumped conceptual models that act in parallel. The advantage of this approach over a fully distributed conceptualisation is that it retains maximum simplicity while taking into account observable landscape characteristics.

  5. Operations and support cost modeling of conceptual space vehicles

    NASA Technical Reports Server (NTRS)

    Ebeling, Charles

    1994-01-01

    The University of Dayton is pleased to submit this annual report to the National Aeronautics and Space Administration (NASA) Langley Research Center which documents the development of an operations and support (O&S) cost model as part of a larger life cycle cost (LCC) structure. It is intended for use during the conceptual design of new launch vehicles and spacecraft. This research is being conducted under NASA Research Grant NAG-1-1327. This research effort changes the focus from that of the first two years in which a reliability and maintainability model was developed to the initial development of an operations and support life cycle cost model. Cost categories were initially patterned after NASA's three axis work breakdown structure consisting of a configuration axis (vehicle), a function axis, and a cost axis. A revised cost element structure (CES), which is currently under study by NASA, was used to established the basic cost elements used in the model. While the focus of the effort was on operations and maintenance costs and other recurring costs, the computerized model allowed for other cost categories such as RDT&E and production costs to be addressed. Secondary tasks performed concurrent with the development of the costing model included support and upgrades to the reliability and maintainability (R&M) model. The primary result of the current research has been a methodology and a computer implementation of the methodology to provide for timely operations and support cost analysis during the conceptual design activities.

  6. Conceptual Modeling in the Time of the Revolution: Part II

    NASA Astrophysics Data System (ADS)

    Mylopoulos, John

    Conceptual Modeling was a marginal research topic at the very fringes of Computer Science in the 60s and 70s, when the discipline was dominated by topics focusing on programs, systems and hardware architectures. Over the years, however, the field has moved to centre stage and has come to claim a central role both in Computer Science research and practice in diverse areas, such as Software Engineering, Databases, Information Systems, the Semantic Web, Business Process Management, Service-Oriented Computing, Multi-Agent Systems, Knowledge Management, and more. The transformation was greatly aided by the adoption of standards in modeling languages (e.g., UML), and model-based methodologies (e.g., Model-Driven Architectures) by the Object Management Group (OMG) and other standards organizations. We briefly review the history of the field over the past 40 years, focusing on the evolution of key ideas. We then note some open challenges and report on-going research, covering topics such as the representation of variability in conceptual models, capturing model intentions, and models of laws.

  7. Design Oriented Structural Modeling for Airplane Conceptual Design Optimization

    NASA Technical Reports Server (NTRS)

    Livne, Eli

    1999-01-01

    The main goal for research conducted with the support of this grant was to develop design oriented structural optimization methods for the conceptual design of airplanes. Traditionally in conceptual design airframe weight is estimated based on statistical equations developed over years of fitting airplane weight data in data bases of similar existing air- planes. Utilization of such regression equations for the design of new airplanes can be justified only if the new air-planes use structural technology similar to the technology on the airplanes in those weight data bases. If any new structural technology is to be pursued or any new unconventional configurations designed the statistical weight equations cannot be used. In such cases any structural weight estimation must be based on rigorous "physics based" structural analysis and optimization of the airframes under consideration. Work under this grant progressed to explore airframe design-oriented structural optimization techniques along two lines of research: methods based on "fast" design oriented finite element technology and methods based on equivalent plate / equivalent shell models of airframes, in which the vehicle is modelled as an assembly of plate and shell components, each simulating a lifting surface or nacelle / fuselage pieces. Since response to changes in geometry are essential in conceptual design of airplanes, as well as the capability to optimize the shape itself, research supported by this grant sought to develop efficient techniques for parametrization of airplane shape and sensitivity analysis with respect to shape design variables. Towards the end of the grant period a prototype automated structural analysis code designed to work with the NASA Aircraft Synthesis conceptual design code ACS= was delivered to NASA Ames.

  8. A Conceptual Titan Orbiter with Probe Mission Using Advanced Radioisotope Power Systems

    NASA Astrophysics Data System (ADS)

    Abelson, Robert D.; Spilker, Thomas R.; Shirley, James H.

    2006-01-01

    With the remarkable success of the Cassini-Huygens mission, considerable new knowledge has been obtained regarding the surface topography, composition and atmospheric characteristics of Titan. However, Cassini-Huygens represents only a bold beginning for the exploration of Titan, as high resolution mapping will have been performed for only a small fraction of the surface of Titan by the end of the nominal mission. Large gaps in knowledge will remain in key scientific areas including global surface topography, atmospheric and surface composition, precipitation rates, and the density, thickness, and formation processes of clouds. This study details a conceptual follow-on Titan orbiter mission that would provide full global topographic coverage, surface imaging, and meteorological characterization of the atmosphere over a nominal 2-year science mission duration. The reference power requirement is ~1 kWe at EOM and is driven by a high power radar instrument that would provide 3-dimensional measurements of atmospheric clouds, precipitation, and surface topography. While this power level is moderately higher than that of the Cassini spacecraft, higher efficiency advanced RPSs could potentially reduce the plutonium usage to less than 1/3 of that used on the Cassini spacecraft. The Titan Orbiter mission is assumed to launch in 2015. It would utilize advanced RPSs to provide all on-board power, and would employ an aeroshell to aerocapture into Titan orbit. A conceptual advanced Stirling RPS was selected due to its high specific power and conversion efficiency which enabled the ability to include a 500 kg ``black box'' deployed entry probe.

  9. Conceptual model of the Klamath Falls, Oregon geothermal area

    SciTech Connect

    Prucha, R.H.; Benson, S.M.; Witherspoon, P.A.

    1987-01-01

    Over the last 50 years significant amounts of data have been obtained from the Klamath Falls geothermal resource. To date, the complexity of the system has stymied researchers, leading to the development of only very generalized hydrogeologic and geothermal models of the area. Recently, the large quantity of available temperature data have been re-evaluated, revealing new information on subsurface heat flow and locations of faults in the system. These inferences are supported by borehole, geochemical, geophysical, and hydrologic data. Based on re-evaluation of all available data, a detailed conceptual model for the Klamath Falls geothermal resource is proposed.

  10. [McEwen's conceptual model in cardiac rehabilitation].

    PubMed

    Desmarais, A; Robichaud-Ekstrand, S

    1998-04-01

    Health motivation is the importance individuals place on their will to persevere, which consequently influences their choice of lifestyle. This article focuses on a relatively new conceptual model that explains cardiac patients' motivation when it comes to initiating and sustaining healthy lifestyle habits. Developed by McEwen in 1993, the Health Motivation Model proposes the following series of variables that influence motivation: previous knowledge, perceived severity, perceived susceptibility, perceived value of action, background variables, internal aids/hindrances, external aids/hindrances and the catalyst. If nurses understand these variables and analyze the patient's case study, they will be better to investigate the origin of cardiac patients' resistance to positive lifestyle changes.

  11. Conceptual Model of the Klamath Falls, Oregon Geothermal Area

    SciTech Connect

    Prucha, R.H.; Benson, S.M.; Witherspoon, P.A.

    1987-01-20

    Over the last 50 years significant amounts of data have been obtained from the Klamath Falls geothermal resource. To date, the complexity of the system has stymied researchers, leading to the development of only very generalized hydrogeologic and geothermal models of the area. Recently, the large quantity of available temperature data have been re-evaluated, revealing new information on subsurface heat flow and locations of faults in the system. These inferences are supported by borehole, geochemical, geophysical, and hydrologic data. Based on re-evaluation of all available data, a detailed conceptual model for the Klamath Falls geothermal resource is proposed. 1 tab., 8 figs., 21 refs.

  12. Advanced Chemistry Basins Model

    SciTech Connect

    Blanco, Mario; Cathles, Lawrence; Manhardt, Paul; Meulbroek, Peter; Tang, Yongchun

    2003-02-13

    The objective of this project is to: (1) Develop a database of additional and better maturity indicators for paleo-heat flow calibration; (2) Develop maturation models capable of predicting the chemical composition of hydrocarbons produced by a specific kerogen as a function of maturity, heating rate, etc.; assemble a compositional kinetic database of representative kerogens; (3) Develop a 4 phase equation of state-flash model that can define the physical properties (viscosity, density, etc.) of the products of kerogen maturation, and phase transitions that occur along secondary migration pathways; (4) Build a conventional basin model and incorporate new maturity indicators and data bases in a user-friendly way; (5) Develop an algorithm which combines the volume change and viscosities of the compositional maturation model to predict the chemistry of the hydrocarbons that will be expelled from the kerogen to the secondary migration pathways; (6) Develop an algorithm that predicts the flow of hydrocarbons along secondary migration pathways, accounts for mixing of miscible hydrocarbon components along the pathway, and calculates the phase fractionation that will occur as the hydrocarbons move upward down the geothermal and fluid pressure gradients in the basin; and (7) Integrate the above components into a functional model implemented on a PC or low cost workstation.

  13. Use of Numerical Groundwater Modeling to Evaluate Uncertainty in Conceptual Models of Recharge and Hydrostratigraphy

    SciTech Connect

    Pohlmann, Karl; Ye, Ming; Pohll, Greg; Chapman, Jenny

    2007-01-19

    Numerical groundwater models are based on conceptualizations of hydrogeologic systems that are by necessity developed from limited information and therefore are simplifications of real conditions. Each aspect (e.g. recharge, hydrostratigraphy, boundary conditions) of the groundwater model is often based on a single conceptual model that is considered to be the best representation given the available data. However, the very nature of their construction means that each conceptual model is inherently uncertain and the available information may be insufficient to refute plausible alternatives, thereby raising the possibility that the flow model is underestimating overall uncertainty. In this study we use the Death Valley Regional Flow System model developed by the U.S. Geological Survey as a framework to predict regional groundwater flow southward into Yucca Flat on the Nevada Test Site. An important aspect of our work is to evaluate the uncertainty associated with multiple conceptual models of groundwater recharge and subsurface hydrostratigraphy and quantify the impacts of this uncertainty on model predictions. In our study, conceptual model uncertainty arises from two sources: (1) alternative interpretations of the hydrostratigraphy in the northern portion of Yucca Flat where, owing to sparse data, the hydrogeologic system can be conceptualized in different ways, and (2) uncertainty in groundwater recharge in the region as evidenced by the existence of several independent approaches for estimating this aspect of the hydrologic system. The composite prediction of groundwater flow is derived from the regional model that formally incorporates the uncertainty in these alternative input models using the maximum likelihood Bayesian model averaging method. An assessment of the joint predictive uncertainty of the input conceptual models is also produced. During this process, predictions of the alternative models are weighted by model probability, which is the degree of

  14. Our evolving conceptual model of the coastal eutrophication problem

    USGS Publications Warehouse

    Cloern, James E.

    2001-01-01

    A primary focus of coastal science during the past 3 decades has been the question: How does anthropogenic nutrient enrichment cause change in the structure or function of nearshore coastal ecosystems? This theme of environmental science is recent, so our conceptual model of the coastal eutrophication problem continues to change rapidly. In this review, I suggest that the early (Phase I) conceptual model was strongly influenced by limnologists, who began intense study of lake eutrophication by the 1960s. The Phase I model emphasized changing nutrient input as a signal, and responses to that signal as increased phytoplankton biomass and primary production, decomposition of phytoplankton-derived organic matter, and enhanced depletion of oxygen from bottom waters. Coastal research in recent decades has identified key differences in the responses of lakes and coastal-estuarine ecosystems to nutrient enrichment. The contemporary (Phase II) conceptual model reflects those differences and includes explicit recognition of (1) system-specific attributes that act as a filter to modulate the responses to enrichment (leading to large differences among estuarine-coastal systems in their sensitivity to nutrient enrichment); and (2) a complex suite of direct and indirect responses including linked changes in: water transparency, distribution of vascular plants and biomass of macroalgae, sediment biogeochemistry and nutrient cycling, nutrient ratios and their regulation of phytoplankton community composition, frequency of toxic/harmful algal blooms, habitat quality for metazoans, reproduction/growth/survival of pelagic and benthic invertebrates, and subtle changes such as shifts in the seasonality of ecosystem functions. Each aspect of the Phase II model is illustrated here with examples from coastal ecosystems around the world. In the last section of this review I present one vision of the next (Phase III) stage in the evolution of our conceptual model, organized around 5

  15. Conceptual Change Texts in Chemistry Teaching: A Study on the Particle Model of Matter

    ERIC Educational Resources Information Center

    Beerenwinkel, Anne; Parchmann, Ilka; Grasel, Cornelia

    2011-01-01

    This study explores the effect of a conceptual change text on students' awareness of common misconceptions on the particle model of matter. The conceptual change text was designed based on principles of text comprehensibility, of conceptual change instruction and of instructional approaches how to introduce the particle model. It was evaluated in…

  16. Family-centered care for children with cerebral palsy: conceptual and practical considerations to advance care and practice.

    PubMed

    King, Gillian; Chiarello, Lisa

    2014-08-01

    This article focuses on conceptual and practical considerations in family-centered care for children with cerebral palsy and their families. In the last 5 years, there have been important advances in our understanding of the components of family-centered care, and initial attempts to understand the client change processes at play. Recent research elaborates on family-centered care by delving into aspects of family-provider partnership, and applying family-centered principles to organizational service delivery to bring about organizational cultures of family-centered care. Recent research has also begun to consider mediators of client change, and new practice models have been proposed that embrace family-centered principles and illustrate the "art" of practice. Future research directions are discussed, including explorations of causal relationships between family-centered care principles, elements of caregiving practice, client change processes, and child and family outcomes. The meaning of the recent literature for pediatric neurology practice is considered. PMID:24810084

  17. Combined Estimation of Hydrogeologic Conceptual Model and Parameter Uncertainty

    SciTech Connect

    Meyer, Philip D.; Ye, Ming; Neuman, Shlomo P.; Cantrell, Kirk J.

    2004-03-01

    The objective of the research described in this report is the development and application of a methodology for comprehensively assessing the hydrogeologic uncertainties involved in dose assessment, including uncertainties associated with conceptual models, parameters, and scenarios. This report describes and applies a statistical method to quantitatively estimate the combined uncertainty in model predictions arising from conceptual model and parameter uncertainties. The method relies on model averaging to combine the predictions of a set of alternative models. Implementation is driven by the available data. When there is minimal site-specific data the method can be carried out with prior parameter estimates based on generic data and subjective prior model probabilities. For sites with observations of system behavior (and optionally data characterizing model parameters), the method uses model calibration to update the prior parameter estimates and model probabilities based on the correspondence between model predictions and site observations. The set of model alternatives can contain both simplified and complex models, with the requirement that all models be based on the same set of data. The method was applied to the geostatistical modeling of air permeability at a fractured rock site. Seven alternative variogram models of log air permeability were considered to represent data from single-hole pneumatic injection tests in six boreholes at the site. Unbiased maximum likelihood estimates of variogram and drift parameters were obtained for each model. Standard information criteria provided an ambiguous ranking of the models, which would not justify selecting one of them and discarding all others as is commonly done in practice. Instead, some of the models were eliminated based on their negligibly small updated probabilities and the rest were used to project the measured log permeabilities by kriging onto a rock volume containing the six boreholes. These four

  18. Advanced Turbulence Modeling Concepts

    NASA Technical Reports Server (NTRS)

    Shih, Tsan-Hsing

    2005-01-01

    The ZCET program developed at NASA Glenn Research Center is to study hydrogen/air injection concepts for aircraft gas turbine engines that meet conventional gas turbine performance levels and provide low levels of harmful NOx emissions. A CFD study for ZCET program has been successfully carried out. It uses the most recently enhanced National combustion code (NCC) to perform CFD simulations for two configurations of hydrogen fuel injectors (GRC- and Sandia-injector). The results can be used to assist experimental studies to provide quick mixing, low emission and high performance fuel injector designs. The work started with the configuration of the single-hole injector. The computational models were taken from the experimental designs. For example, the GRC single-hole injector consists of one air tube (0.78 inches long and 0.265 inches in diameter) and two hydrogen tubes (0.3 inches long and 0.0226 inches in diameter opposed at 180 degree). The hydrogen tubes are located 0.3 inches upstream from the exit of the air element (the inlet location for the combustor). To do the simulation, the single-hole injector is connected to a combustor model (8.16 inches long and 0.5 inches in diameter). The inlet conditions for air and hydrogen elements are defined according to actual experimental designs. Two crossing jets of hydrogen/air are simulated in detail in the injector. The cold flow, reacting flow, flame temperature, combustor pressure and possible flashback phenomena are studied. Two grid resolutions of the numerical model have been adopted. The first computational grid contains 0.52 million elements, the second one contains over 1.3 million elements. The CFD results have shown only about 5% difference between the two grid resolutions. Therefore, the CFD result obtained from the model of 1.3-million grid resolution can be considered as a grid independent numerical solution. Turbulence models built in NCC are consolidated and well tested. They can handle both coarse and

  19. Regionalization parameters of conceptual rainfall-runoff model

    NASA Astrophysics Data System (ADS)

    Osuch, M.

    2003-04-01

    Main goal of this study was to develop techniques for the a priori estimation parameters of hydrological model. Conceptual hydrological model CLIRUN was applied to around 50 catchment in Poland. The size of catchments range from 1 000 to 100 000 km2. The model was calibrated for a number of gauged catchments with different catchment characteristics. The parameters of model were related to different climatic and physical catchment characteristics (topography, land use, vegetation and soil type). The relationships were tested by comparing observed and simulated runoff series from the gauged catchment that were not used in the calibration. The model performance using regional parameters was promising for most of the calibration and validation catchments.

  20. Development and Validation of a Mass Casualty Conceptual Model

    PubMed Central

    Culley, Joan M.; Effken, Judith A.

    2012-01-01

    Purpose To develop and validate a conceptual model that provides a framework for the development and evaluation of information systems for mass casualty events. Design The model was designed based on extant literature and existing theoretical models. A purposeful sample of 18 experts validated the model. Open-ended questions, as well as a 7-point Likert scale, were used to measure expert consensus on the importance of each construct and its relationship in the model and the usefulness of the model to future research. Methods Computer-mediated applications were used to facilitate a modified Delphi technique through which a panel of experts provided validation for the conceptual model. Rounds of questions continued until consensus was reached, as measured by an interquartile range (no more than 1 scale point for each item); stability (change in the distribution of responses less than 15% between rounds); and percent agreement (70% or greater) for indicator questions. Findings Two rounds of the Delphi process were needed to satisfy the criteria for consensus or stability related to the constructs, relationships, and indicators in the model. The panel reached consensus or sufficient stability to retain all 10 constructs, 9 relationships, and 39 of 44 indicators. Experts viewed the model as useful (mean of 5.3 on a 7-point scale). Conclusions Validation of the model provides the first step in understanding the context in which mass casualty events take place and identifying variables that impact outcomes of care. Clinical Relevance This study provides a foundation for understanding the complexity of mass casualty care, the roles that nurses play in mass casualty events, and factors that must be considered in designing and evaluating information-communication systems to support effective triage under these conditions. PMID:20487188

  1. Conceptual database modeling: a method for enabling end users (radiologists) to understand and develop their information management applications.

    PubMed

    Hawkins, H; Young, S K; Hubert, K C; Hallock, P

    2001-06-01

    As medical technology advances at a rapid pace, clinicians become further and further removed from the design of their own technological tools. This is particularly evident with information management. For radiologists, clinical histories, patient reports, and other pertinent information require sophisticated tools for data handling. However, as databases grow more powerful and sophisticated, systems require the expertise of programmers and information technology personnel. The radiologist, the clinician end-user, must maintain involvement in the development of system tools to insure effective information management. Conceptual database modeling is a design method that serves to bridge the gap between the technological aspects of information management and its clinical applications. Conceptual database modeling involves developing information systems in simple language so that anyone can have input into the overall design. This presentation describes conceptual database modeling, using object role modeling, as a means by which end-users (clinicians) may participate in database development.

  2. Advanced heat receiver conceptual design study. Final report, May 1986-July 1988

    SciTech Connect

    Kesseli, J.; Saunders, R.; Batchelder, G.

    1988-10-01

    Solar dynamic space power systems are candidate electrical power generating systems for future NASA missions. One of the key components of the solar dynamic power system is the solar receiver/thermal energy storage (TES) subsystem. Receiver development was conducted by NASA in the late 1960's and since then a very limited amount of work has been done in this area. Consequently the state of the art (SOA) receivers designed for the IOC space station are large and massive. The objective of the Advanced Heat Receiver Conceptual Design Study is to conceive and analyze advanced high temperature solar dynamic Brayton and Stirling receivers. The goal is to generate innovative receiver concepts that are half of the mass, smaller, and more efficient than the SOA. It is also necessary that these innovative receivers offer ease of manufacturing, less structural complexity and fewer thermal stress problems. Advanced Brayton and Stirling receiver storage units are proposed and analyzed in this study which can potentially meet these goals.

  3. Loss, Psychosis, and Chronic Suicidality in a Korean American Immigrant Man: Integration of Cultural Formulation Model and Multicultural Case Conceptualization

    PubMed Central

    Shea, Munyi; Yang, Lawrence H.; Leong, Frederick T. L.

    2011-01-01

    Culture shapes the nature, experience, and expression of psychopathology and help-seeking behavior across ethnically diverse groups. Although the study of psychopathology among Asian Americans has advanced, clinicians remain in need of culturally appropriate tools for the assessment and diagnosis of severe mental disorders including psychotic symptoms among Asian Americans. In this article, we present a brief overview of two culturally relevant conceptual tools: a) the Cultural Formulation Model, and b) the Multicultural Case Conceptualization approach. We use a case scenario to illustrate the integration of these two approaches in providing culturally responsive clinical conceptualization, assessment and treatment of a Korean American immigrant suffering from prominent psychiatric symptoms. We intend this discussion to engender further empirical work to advance our knowledge of the manifestation and experience of severe mental illness including psychotic disorders among Asian Americans, and contribute to culturally competent prevention and intervention of chronic and persistent mental illness within this group. PMID:21603157

  4. Conceptual design of an advanced Stirling conversion system for terrestrial power generation

    NASA Technical Reports Server (NTRS)

    1988-01-01

    A free piston Stirling engine coupled to an electric generator or alternator with a nominal kWe power output absorbing thermal energy from a nominal 100 square meter parabolic solar collector and supplying electric power to a utility grid was identified. The results of the conceptual design study of an Advanced Stirling Conversion System (ASCS) were documented. The objectives are as follows: define the ASCS configuration; provide a manufacturability and cost evaluation; predict ASCS performance over the range of solar input required to produce power; estimate system and major component weights; define engine and electrical power condidtioning control requirements; and define key technology needs not ready by the late 1980s in meeting efficiency, life, cost, and with goalds for the ASCS.

  5. Advanced conceptual design report solid waste retrieval facility, phase I, project W-113

    SciTech Connect

    Smith, K.E.

    1994-03-21

    Project W-113 will provide the equipment and facilities necessary to retrieve suspect transuranic (TRU) waste from Trench 04 of the 218W-4C burial ground. As part of the retrieval process, waste drums will be assayed, overpacked, vented, head-gas sampled, and x-rayed prior to shipment to the Phase V storage facility in preparation for receipt at the Waste Receiving and Processing Facility (WRAP). Advanced Conceptual Design (ACD) studies focused on project items warranting further definition prior to Title I design and areas where the potential for cost savings existed. This ACD Report documents the studies performed during FY93 to optimize the equipment and facilities provided in relation to other SWOC facilities and to provide additional design information for Definitive Design.

  6. A conceptual model of public medical service system based-on cell phone mobile platform

    NASA Astrophysics Data System (ADS)

    Fu, Hongjiao; Zhao, Yue

    In recent years, cell phones have played an increasingly important role in rapidly-developing global telecommunication services. At present, mobile business develops very fast. However, the development in other mobile service fields, such as public service, mobile medical service, etc, is still in its infant stage. Drawing on the experience of the 'doctor workstation project' which is cooperated by Renmin University of China and Norway Fredskorps Corporation, this paper discusses the research and implementation of the Doctor Workstation System based on cell phone mobile platform. From the practice of the Doctor Workstation System, the paper advances a conceptual model of public medical service system based-on cell phone mobile platform.

  7. Conceptual Modeling for the Unified Medical Language System

    PubMed Central

    Barr, Charles E.; Komorowski, Henryk Jan; Pattison-Gordon, Edward; Greenes, Robert A.

    1988-01-01

    The Unified Medical Language System was proposed by the National Library of Medicine to facilitate the exchange and utilization of information from multiple sources. We are using semantic networks as the knowledge representation scheme in a prototype system to explore how to accomplish these goals. Conceptual modeling helps define a complete and consistent set of objects and relationships to include in the semantic net. Both top-down and bottom-up approaches were found useful in the seven step process of building the semantic network. Theoretical and practical issues are discussed as well as future extensions to the current prototype.

  8. Determinants of access to pediatric hospice care: A conceptual model

    PubMed Central

    Lindley, Lisa C.

    2014-01-01

    One of the many difficult moments for families of children with life-limiting illnesses is to make the decision to access pediatric hospice care. Although determinants that influence families’ decisions to access pediatric hospice care have been recently identified, the relationship between these determinants and access to pediatric hospice care have not been explicated or grounded in accepted healthcare theories or models. Using the Andersen Behavioral Healthcare Utilization Model, this article presents a conceptual model describing the determinants of hospice access. Predisposing (demographic; social support; and knowledge, beliefs, and values), enabling (family and community resources) and need (perceived and evaluated needs) factors were identified through the use of hospice literature. The relationships among these factors are described and implications of the model for future study and practice are discussed. PMID:25983662

  9. Conceptual Modeling of mRNA Decay Provokes New Hypotheses

    PubMed Central

    Somekh, Judith; Haimovich, Gal; Guterman, Adi; Dori, Dov; Choder, Mordechai

    2014-01-01

    Biologists are required to integrate large amounts of data to construct a working model of the system under investigation. This model is often informal and stored mentally or textually, making it prone to contain undetected inconsistencies, inaccuracies, or even contradictions, not much less than a representation in free natural language. Using Object-Process Methodology (OPM), a formal yet visual and humanly accessible conceptual modeling language, we have created an executable working model of the mRNA decay process in Saccharomyces cerevisiae, as well as the import of its components to the nucleus following mRNA decay. We show how our model, which incorporates knowledge from 43 articles, can reproduce outcomes that match the experimental findings, evaluate hypotheses, and predict new possible outcomes. Moreover, we were able to analyze the effects of the mRNA decay model perturbations related to gene and interaction deletions, and predict the nuclear import of certain decay factors, which we then verified experimentally. In particular, we verified experimentally the hypothesis that Rpb4p, Lsm1p, and Pan2p remain bound to the RNA 3′-untralslated region during the entire process of the 5′ to 3′ degradation of the RNA open reading frame. The model has also highlighted erroneous hypotheses that indeed were not in line with the experimental outcomes. Beyond the scientific value of these specific findings, this work demonstrates the value of the conceptual model as an in silico vehicle for hypotheses generation and testing, which can reinforce, and often even replace, risky, costlier wet lab experiments. PMID:25255440

  10. ADVANCED MIXING MODELS

    SciTech Connect

    Lee, S; Richard Dimenna, R; David Tamburello, D

    2008-11-13

    The process of recovering the waste in storage tanks at the Savannah River Site (SRS) typically requires mixing the contents of the tank with one to four dual-nozzle jet mixers located within the tank. The typical criteria to establish a mixed condition in a tank are based on the number of pumps in operation and the time duration of operation. To ensure that a mixed condition is achieved, operating times are set conservatively long. This approach results in high operational costs because of the long mixing times and high maintenance and repair costs for the same reason. A significant reduction in both of these costs might be realized by reducing the required mixing time based on calculating a reliable indicator of mixing with a suitably validated computer code. The work described in this report establishes the basis for further development of the theory leading to the identified mixing indicators, the benchmark analyses demonstrating their consistency with widely accepted correlations, and the application of those indicators to SRS waste tanks to provide a better, physically based estimate of the required mixing time. Waste storage tanks at SRS contain settled sludge which varies in height from zero to 10 ft. The sludge has been characterized and modeled as micron-sized solids, typically 1 to 5 microns, at weight fractions as high as 20 to 30 wt%, specific gravities to 1.4, and viscosities up to 64 cp during motion. The sludge is suspended and mixed through the use of submersible slurry jet pumps. To suspend settled sludge, water is added to the tank as a slurry medium and stirred with the jet pump. Although there is considerable technical literature on mixing and solid suspension in agitated tanks, very little literature has been published on jet mixing in a large-scale tank. If shorter mixing times can be shown to support Defense Waste Processing Facility (DWPF) or other feed requirements, longer pump lifetimes can be achieved with associated operational cost and

  11. ADVANCED MIXING MODELS

    SciTech Connect

    Lee, S; Dimenna, R; Tamburello, D

    2011-02-14

    height from zero to 10 ft. The sludge has been characterized and modeled as micron-sized solids, typically 1 to 5 microns, at weight fractions as high as 20 to 30 wt%, specific gravities to 1.4, and viscosities up to 64 cp during motion. The sludge is suspended and mixed through the use of submersible slurry jet pumps. To suspend settled sludge, water is added to the tank as a slurry medium and stirred with the jet pump. Although there is considerable technical literature on mixing and solid suspension in agitated tanks, very little literature has been published on jet mixing in a large-scale tank. One of the main objectives in the waste processing is to provide feed of a uniform slurry composition at a certain weight percentage (e.g. typically {approx}13 wt% at SRS) over an extended period of time. In preparation of the sludge for slurrying, several important questions have been raised with regard to sludge suspension and mixing of the solid suspension in the bulk of the tank: (1) How much time is required to prepare a slurry with a uniform solid composition? (2) How long will it take to suspend and mix the sludge for uniform composition in any particular waste tank? (3) What are good mixing indicators to answer the questions concerning sludge mixing stated above in a general fashion applicable to any waste tank/slurry pump geometry and fluid/sludge combination?

  12. An analogue conceptual rainfall-runoff model for educational purposes

    NASA Astrophysics Data System (ADS)

    Herrnegger, Mathew; Riedl, Michael; Schulz, Karsten

    2016-04-01

    Conceptual rainfall-runoff models, in which runoff processes are modelled with a series of connected linear and non-linear reservoirs, remain widely applied tools in science and practice. Additionally, the concept is appreciated in teaching due to its somewhat simplicity in explaining and exploring hydrological processes of catchments. However, when a series of reservoirs are used, the model system becomes highly parametrized and complex and the traceability of the model results becomes more difficult to explain to an audience not accustomed to numerical modelling. Since normally the simulations are performed with a not visible digital code, the results are also not easily comprehensible. This contribution therefore presents a liquid analogue model, in which a conceptual rainfall-runoff model is reproduced by a physical model. This consists of different acrylic glass containers representing different storage components within a catchment, e.g. soil water or groundwater storage. The containers are equipped and connected with pipes, in which water movement represents different flow processes, e.g. surface runoff, percolation or base flow. Water from a storage container is pumped to the upper part of the model and represents effective rainfall input. The water then flows by gravity through the different pipes and storages. Valves are used for controlling the flows within the analogue model, comparable to the parameterization procedure in numerical models. Additionally, an inexpensive microcontroller-based board and sensors are used to measure storage water levels, with online visualization of the states as time series data, building a bridge between the analogue and digital world. The ability to physically witness the different flows and water levels in the storages makes the analogue model attractive to the audience. Hands-on experiments can be performed with students, in which different scenarios or catchment types can be simulated, not only with the analogue but

  13. Development of a conceptual model of cancer caregiver health literacy.

    PubMed

    Yuen, E Y N; Dodson, S; Batterham, R W; Knight, T; Chirgwin, J; Livingston, P M

    2016-03-01

    Caregivers play a vital role in caring for people diagnosed with cancer. However, little is understood about caregivers' capacity to find, understand, appraise and use information to improve health outcomes. The study aimed to develop a conceptual model that describes the elements of cancer caregiver health literacy. Six concept mapping workshops were conducted with 13 caregivers, 13 people with cancer and 11 healthcare providers/policymakers. An iterative, mixed methods approach was used to analyse and synthesise workshop data and to generate the conceptual model. Six major themes and 17 subthemes were identified from 279 statements generated by participants during concept mapping workshops. Major themes included: access to information, understanding of information, relationship with healthcare providers, relationship with the care recipient, managing challenges of caregiving and support systems. The study extends conceptualisations of health literacy by identifying factors specific to caregiving within the cancer context. The findings demonstrate that caregiver health literacy is multidimensional, includes a broad range of individual and interpersonal elements, and is influenced by broader healthcare system and community factors. These results provide guidance for the development of: caregiver health literacy measurement tools; strategies for improving health service delivery, and; interventions to improve caregiver health literacy.

  14. Updated Conceptual Model for the 300 Area Uranium Groundwater Plume

    SciTech Connect

    Zachara, John M.; Freshley, Mark D.; Last, George V.; Peterson, Robert E.; Bjornstad, Bruce N.

    2012-11-01

    The 300 Area uranium groundwater plume in the 300-FF-5 Operable Unit is residual from past discharge of nuclear fuel fabrication wastes to a number of liquid (and solid) disposal sites. The source zones in the disposal sites were remediated by excavation and backfilled to grade, but sorbed uranium remains in deeper, unexcavated vadose zone sediments. In spite of source term removal, the groundwater plume has shown remarkable persistence, with concentrations exceeding the drinking water standard over an area of approximately 1 km2. The plume resides within a coupled vadose zone, groundwater, river zone system of immense complexity and scale. Interactions between geologic structure, the hydrologic system driven by the Columbia River, groundwater-river exchange points, and the geochemistry of uranium contribute to persistence of the plume. The U.S. Department of Energy (DOE) recently completed a Remedial Investigation/Feasibility Study (RI/FS) to document characterization of the 300 Area uranium plume and plan for beginning to implement proposed remedial actions. As part of the RI/FS document, a conceptual model was developed that integrates knowledge of the hydrogeologic and geochemical properties of the 300 Area and controlling processes to yield an understanding of how the system behaves and the variables that control it. Recent results from the Hanford Integrated Field Research Challenge site and the Subsurface Biogeochemistry Scientific Focus Area Project funded by the DOE Office of Science were used to update the conceptual model and provide an assessment of key factors controlling plume persistence.

  15. A conceptual model for translating omic data into clinical action

    PubMed Central

    Herr, Timothy M.; Bielinski, Suzette J.; Bottinger, Erwin; Brautbar, Ariel; Brilliant, Murray; Chute, Christopher G.; Denny, Joshua; Freimuth, Robert R.; Hartzler, Andrea; Kannry, Joseph; Kohane, Isaac S.; Kullo, Iftikhar J.; Lin, Simon; Pathak, Jyotishman; Peissig, Peggy; Pulley, Jill; Ralston, James; Rasmussen, Luke; Roden, Dan; Tromp, Gerard; Williams, Marc S.; Starren, Justin

    2015-01-01

    Genomic, proteomic, epigenomic, and other “omic” data have the potential to enable precision medicine, also commonly referred to as personalized medicine. The volume and complexity of omic data are rapidly overwhelming human cognitive capacity, requiring innovative approaches to translate such data into patient care. Here, we outline a conceptual model for the application of omic data in the clinical context, called “the omic funnel.” This model parallels the classic “Data, Information, Knowledge, Wisdom pyramid” and adds context for how to move between each successive layer. Its goal is to allow informaticians, researchers, and clinicians to approach the problem of translating omic data from bench to bedside, by using discrete steps with clearly defined needs. Such an approach can facilitate the development of modular and interoperable software that can bring precision medicine into widespread practice. PMID:26430534

  16. A conceptual model for translating omic data into clinical action.

    PubMed

    Herr, Timothy M; Bielinski, Suzette J; Bottinger, Erwin; Brautbar, Ariel; Brilliant, Murray; Chute, Christopher G; Denny, Joshua; Freimuth, Robert R; Hartzler, Andrea; Kannry, Joseph; Kohane, Isaac S; Kullo, Iftikhar J; Lin, Simon; Pathak, Jyotishman; Peissig, Peggy; Pulley, Jill; Ralston, James; Rasmussen, Luke; Roden, Dan; Tromp, Gerard; Williams, Marc S; Starren, Justin

    2015-01-01

    Genomic, proteomic, epigenomic, and other "omic" data have the potential to enable precision medicine, also commonly referred to as personalized medicine. The volume and complexity of omic data are rapidly overwhelming human cognitive capacity, requiring innovative approaches to translate such data into patient care. Here, we outline a conceptual model for the application of omic data in the clinical context, called "the omic funnel." This model parallels the classic "Data, Information, Knowledge, Wisdom pyramid" and adds context for how to move between each successive layer. Its goal is to allow informaticians, researchers, and clinicians to approach the problem of translating omic data from bench to bedside, by using discrete steps with clearly defined needs. Such an approach can facilitate the development of modular and interoperable software that can bring precision medicine into widespread practice. PMID:26430534

  17. A conceptual model for growing evidence-based practice.

    PubMed

    Vratny, Amy; Shriver, Deb

    2007-01-01

    Nursing administration at a small medical center is developing and implementing an evidence-based practice (EBP) model of care to support a culture of quality care, clinical excellence, cost-effectiveness, critical thinking, empowerment of staff, and professional growth. The purpose of this article is to describe a conceptual model for EBP that addresses how to overcome barriers to implementation. Clinician expertise and values, experience, patient preference and expectation, and caring become grounded in a practice environment that must strive to become rooted in clinical research to evolve into a practice that is evidence-based. Education helps to nourish EBP, but leadership, enthusiasm, mentorship, clinical inquiry, and reflective practice make EBP thrive. The EBP ambassadors branch out to each department to grow journal clubs, EBP Web pages, EBP projects, research utilization projects, and staff-led practice reviews. The fruits are quality patient care and outcomes, clinical excellence, cost-effectiveness, critical thinking, empowerment of staff, and professional growth.

  18. Evaluation of ADAM/1 model for advanced coal extraction concepts

    NASA Technical Reports Server (NTRS)

    Deshpande, G. K.; Gangal, M. D.

    1982-01-01

    Several existing computer programs for estimating life cycle cost of mining systems were evaluated. A commercially available program, ADAM/1 was found to be satisfactory in relation to the needs of the advanced coal extraction project. Two test cases were run to confirm the ability of the program to handle nonconventional mining equipment and procedures. The results were satisfactory. The model, therefore, is recommended to the project team for evaluation of their conceptual designs.

  19. Forensic isotope analysis to refine a hydrologic conceptual model.

    PubMed

    Bassett, R L; Steinwand, Aaron; Jorat, Saeed; Petersen, Christian; Jackson, Randy

    2008-01-01

    Water resources in the arid southwestern United States are frequently the subject of conflict from competing private and public interests. Legal remedies may remove impasses, but the technical analysis of the problem often determines the future success of legal solutions. In Owens Valley, California, the source of water for the Los Angeles Aqueduct (LAA) is flow diverted from the Owens River and its tributaries and ground water from valley aquifers. Future management of ground water delivered to the LAA needs technical support regarding quantity available, interconnection of shallow and confined aquifers, impact on local springs, and rate of recharge. Ground water flow models and ground water composition are tools already in use, but these have large uncertainty for local interpretations. This study conducted targeted sampling of springs and wells to evaluate the hydrologic system to corroborate conceptual and numerical models. The effort included measurement of intrinsic isotopic composition at key locations in the aquifers. The stable isotopic data of boron (delta(11)B), sulfur (delta(34)S), oxygen (delta(18)O), hydrogen (delta D), and tritium ((3)H) supported by basic chemical data provided rules for characterizing the upper and the lower aquifer system, confirmed the interpretation of ground water flow near faults and flow barriers, and detected hydraulic connections between the LAA and the perennial springs at key locations along the unlined reach of the LAA. This study exemplifies the use of forensic isotopic approaches as independent checks on the consistency of interpretations of conceptual models of a ground water system and the numerical hydrologic simulations.

  20. Setting health research priorities using the CHNRI method: IV. Key conceptual advances

    PubMed Central

    Rudan, Igor

    2016-01-01

    Introduction Child Health and Nutrition Research Initiative (CHNRI) started as an initiative of the Global Forum for Health Research in Geneva, Switzerland. Its aim was to develop a method that could assist priority setting in health research investments. The first version of the CHNRI method was published in 2007–2008. The aim of this paper was to summarize the history of the development of the CHNRI method and its key conceptual advances. Methods The guiding principle of the CHNRI method is to expose the potential of many competing health research ideas to reduce disease burden and inequities that exist in the population in a feasible and cost–effective way. Results The CHNRI method introduced three key conceptual advances that led to its increased popularity in comparison to other priority–setting methods and processes. First, it proposed a systematic approach to listing a large number of possible research ideas, using the “4D” framework (description, delivery, development and discovery research) and a well–defined “depth” of proposed research ideas (research instruments, avenues, options and questions). Second, it proposed a systematic approach for discriminating between many proposed research ideas based on a well–defined context and criteria. The five “standard” components of the context are the population of interest, the disease burden of interest, geographic limits, time scale and the preferred style of investing with respect to risk. The five “standard” criteria proposed for prioritization between research ideas are answerability, effectiveness, deliverability, maximum potential for disease burden reduction and the effect on equity. However, both the context and the criteria can be flexibly changed to meet the specific needs of each priority–setting exercise. Third, it facilitated consensus development through measuring collective optimism on each component of each research idea among a larger group of experts using a simple

  1. Conceptual geoinformation model of natural hazards risk assessment

    NASA Astrophysics Data System (ADS)

    Kulygin, Valerii

    2016-04-01

    Natural hazards are the major threat to safe interactions between nature and society. The assessment of the natural hazards impacts and their consequences is important in spatial planning and resource management. Today there is a challenge to advance our understanding of how socio-economical and climate changes will affect the frequency and magnitude of hydro-meteorological hazards and associated risks. However, the impacts from different types of natural hazards on various marine and coastal economic activities are not of the same type. In this study, the conceptual geomodel of risk assessment is presented to highlight the differentiation by the type of economic activities in extreme events risk assessment. The marine and coastal ecosystems are considered as the objects of management, on the one hand, and as the place of natural hazards' origin, on the other hand. One of the key elements in describing of such systems is the spatial characterization of their components. Assessment of ecosystem state is based on ecosystem indicators (indexes). They are used to identify the changes in time. The scenario approach is utilized to account for the spatio-temporal dynamics and uncertainty factors. Two types of scenarios are considered: scenarios of using ecosystem services by economic activities and scenarios of extreme events and related hazards. The reported study was funded by RFBR, according to the research project No. 16-35-60043 mol_a_dk.

  2. Conceptual model and map of financial exploitation of older adults.

    PubMed

    Conrad, Kendon J; Iris, Madelyn; Ridings, John W; Fairman, Kimberly P; Rosen, Abby; Wilber, Kathleen H

    2011-10-01

    This article describes the processes and outcomes of three-dimensional concept mapping to conceptualize financial exploitation of older adults. Statements were generated from a literature review and by local and national panels consisting of 16 experts in the field of financial exploitation. These statements were sorted and rated using Concept Systems software, which grouped the statements into clusters and depicted them as a map. Statements were grouped into six clusters, and ranked by the experts as follows in descending severity: (a) theft and scams, (b) financial victimization, (c) financial entitlement, (d) coercion, (e) signs of possible financial exploitation, and (f) money management difficulties. The hierarchical model can be used to identify elder financial exploitation and differentiate it from related but distinct areas of victimization. The severity hierarchy may be used to develop measures that will enable more precise screening for triage of clients into appropriate interventions.

  3. Toward a conceptual model of floodplain water table response

    NASA Astrophysics Data System (ADS)

    Jung, M.; Burt, T. P.; Bates, P. D.

    2004-12-01

    Hydrological processes operating within floodplains in temperate midlatitudes have significant implications for water management by controlling pollutant transfer between the catchment and the fluvial system. However, there is a lack of relevant high-resolution data from which the dynamics of floodplain hydrology during flood events can be inferred. A detailed analysis of water table fluctuations during flood events within a typical European lowland floodplain system (River Severn, United Kingdom) is presented. Data collected hourly along two 120-meter-long transects, each comprising four piezometers, plus one river stage sensor, are analyzed for the winter season 1998-1999 using correlation analysis, hysteresis curves, and water table maps. The objective is to develop a conceptual model that provides mechanistic understanding of floodplain water table response during flood events. River stage is shown to be the principal driver of water table fluctuations. Piezometers with similar water table response are identified; their consistent pattern of response in different flood events is attributed to sedimentary and morphological controls on the floodplain and adjoining hillslopes. Deviations from the general pattern are a function of low antecedent soil moisture, which is only a significant factor at the beginning of the winter season, when the floodplain is initially dry. Our conceptual model adopts a kinematic wave process whereby river stage change induces rapid responses of the water table over many tens of meters across the floodplain, associated with flux velocities several orders of magnitude higher than would be expected for Darcian flow. The occurrence of a groundwater ridge within the floodplain dams hillslope drainage and causes the water table to rise at the back of the floodplain. The disappearance of the groundwater ridge during the recession reestablishes hillslope flow into the floodplain, resulting in significant three-dimensional hydraulic gradients

  4. Conceptual design study of advanced acoustic composite nacelle. [for achieving reductions in community noise and operating expense

    NASA Technical Reports Server (NTRS)

    Goodall, R. G.; Painter, G. W.

    1975-01-01

    Conceptual nacelle designs for wide-bodied and for advanced-technology transports were studied with the objective of achieving significant reductions in community noise with minimum penalties in airplane weight, cost, and in operating expense by the application of advanced composite materials to nacelle structure and sound suppression elements. Nacelle concepts using advanced liners, annular splitters, radial splitters, translating centerbody inlets, and mixed-flow nozzles were evaluated and a preferred concept selected. A preliminary design study of the selected concept, a mixed flow nacelle with extended inlet and no splitters, was conducted and the effects on noise, direct operating cost, and return on investment determined.

  5. Advanced turbine systems program conceptual design and product development. Quarterly report, February 1995--April 1995

    SciTech Connect

    Karstensen, K.W.

    1995-07-01

    This Quarterly Technical Progress Report covers the period February 1, 1995, through April 30, 1995, for Phase II of the Advanced Turbine Systems (ATS) Program by Solar Turbines Incorporated under DOE contract No. DE-AC21-93MC30246. The objective of Phase II of the ATS Program is to provide the conceptual design and product development plan for an ultra high efficiency, environmentally superior and cost competitive industrial gas turbine system to be commercialized by the year 2000. A secondary objective is to begin early development of technologies critical to the success of ATS. Tasks 1, 2, 3, 5, 6 and 7 of Phase II have been completed in prior quarters. Their results have been discussed in the applicable quarterly reports and in their respective topical reports. With the exception of Task 7, final editions of these topical reports have been submitted to the DOE. This quarterly report, then, addresses only Task 4 and the nine subtasks included in Task 8, {open_quotes}Design and Test of Critical Components.{close_quotes} These nine subtasks address six ATS technologies as follows: (1) Catalytic Combustion - Subtasks 8.2 and 8.5, (2) Recuperator - Subtasks 8.1 and 8.7, (3) Autothermal Fuel Reformer - Subtask 8.3, (4) High Temperature Turbine Disc - Subtask 8.4, (5) Advanced Control System (MMI) - Subtask 8.6, and (6) Ceramic Materials - Subtasks 8.8 and 8.9. Major technological achievements from Task 8 efforts during the quarter are as follows: (1) The subscale catalytic combustion rig in Subtask 8.2 is operating consistently at 3 ppmv of NO{sub x} over a range of ATS operating conditions. (2) The spray cast process used to produce the rim section of the high temperature turbine disc of Subtask 8.4 offers additional and unplanned spin-off opportunities for low cost manufacture of certain gas turbine parts.

  6. Advanced turbine systems program conceptual design and product development. Annual report, August 1993--July 1994

    SciTech Connect

    1994-11-01

    This Yearly Technical Progress Report covers the period August 3, 1993 through July 31, 1994 for Phase 2 of the Advanced Turbine Systems (ATS) Program by Solar Turbines Incorporated under DOE Contract No. DE-AC421-93MC30246. As allowed by the Contract (Part 3, Section J, Attachment B) this report is also intended to fulfill the requirements for a fourth quarterly report. The objective of Phase 2 of the ATS Program is to provide the conceptual design and product development plan for an ultra-high efficiency, environmentally superior and cost-competitive industrial gas turbine system to be commercialized in the year 2000. During the period covered by this report, Solar has completed three of eight program tasks and has submitted topical reports. These three tasks included a Project Plan submission of information required by NEPA, and the selection of a Gas-Fueled Advanced Turbine System (GFATS). In the latest of the three tasks, Solar`s Engineering team identified an intercooled and recuperated (ICR) gas turbine as the eventual outcome of DOE`s ATS program coupled with Solar`s internal New Product Introduction (NPI) program. This machine, designated ``ATS50`` will operate at a thermal efficiency (turbine shaft power/fuel LHV) of 50 percent, will emit less than 10 parts per million of NOx and will reduce the cost of electricity by 10 percent. It will also demonstrate levels of reliability, availability, maintainability, and durability (RAMD) equal to or better than those of today`s gas turbine systems. Current activity is concentrated in three of the remaining five tasks a Market Study, GFATS System Definition and Analysis, and the Design and Test of Critical Components.

  7. Biconic cargo return vehicle with an advanced recovery system. Volume 1: Conceptual design

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The conceptual design of the biconic Cargo Return Vehicle (CRV) is presented. The CRV will be able to meet all of the Space Station Freedom (SSF's) resupply needs. Worth note is the absence of a backup recovery chute in case of Advanced Recovery System (ARS) failure. The high reliability of ram-air parachutes does not warrant the penalty weight that such a system would create on successful missions. The CRV will launch vertically integrated with an Liquid Rocket Booster (LRB) vehicle and meets all NASA restrictions on fuel type for all phases of the mission. Because of the downscaled Orbital Maneuvering Vehicle (OMV) program, the CRV has been designed to be able to transfer cargo by docking directly to the Space Station Freedom as well as with OMV assistance. The CRV will cover enough crossrange to reach its primary landing site, Edwards Airforce Base, and all secondary landing sites with the exception of one orbit. Transportation back to KSC will be via the Boeing Super Guppy. Due to difficulties with man-rating the CRV, it will not be used in a CERV role. A brief summary of the CRV's specifications is given.

  8. Conceptual design study for an advanced cab and visual system, volume 1

    NASA Technical Reports Server (NTRS)

    Rue, R. J.; Cyrus, M. L.; Garnett, T. A.; Nachbor, J. W.; Seery, J. A.; Starr, R. L.

    1980-01-01

    A conceptual design study was conducted to define requirements for an advanced cab and visual system. The rotorcraft system integration simulator is for engineering studies in the area of mission associated vehicle handling qualities. Principally a technology survey and assessment of existing and proposed simulator visual display systems, image generation systems, modular cab designs, and simulator control station designs were performed and are discussed. State of the art survey data were used to synthesize a set of preliminary visual display system concepts of which five candidate display configurations were selected for further evaluation. Basic display concepts incorporated in these configurations included: real image projection, using either periscopes, fiber optic bundles, or scanned laser optics; and virtual imaging with helmet mounted displays. These display concepts were integrated in the study with a simulator cab concept employing a modular base for aircraft controls, crew seating, and instrumentation (or other) displays. A simple concept to induce vibration in the various modules was developed and is described. Results of evaluations and trade offs related to the candidate system concepts are given, along with a suggested weighting scheme for numerically comparing visual system performance characteristics.

  9. Requirements for the conceptual design of advanced underground coal-extraction systems

    SciTech Connect

    Gangal, M.D.; Lavin, M.L.

    1981-12-15

    This document presents conceptual design requirements for underground coal mining systems having substantially improved performance in the areas of production cost and miner safety. Mandatory performance levels are also set for miner health, environmental impact, and coal recovery. In addition to mandatory design goals and constraints, the document identifies a number of desirable system characteristics which must be assessed in terms of their impact on production cost and their compatibility with other system elements. Although developed for the flat-lying, moderately thick seams of Central Appalachia, these requirements are designed to be easily adaptable to other coals. This document results from the initial phase of a program to define, develop, and demonstrate advanced equipment suitable for the resources remaining beyond the year 2000. The requirements developed are meant to implement the broad systems performance goals formulated by Goldsmith and Lavin (1980) by providing a rational point of departure for the design of underground mining systems with emphasis on Central Appalachian coals. Because no one has yet attempted to design to these requirements, they may contain some inconsistencies and need clarification in some areas. Accordingly, the authors would very much appreciate commments and suggestions from those who have used or critically reviewed these requirements.

  10. Hydrodynamics of burst swimming fish larvae; a conceptual model approach.

    PubMed

    Verhagen, Jan H G

    2004-07-21

    Burst swimming of fish larvae is analysed from a hydrodynamic point of view. A picture of the expected flow pattern is presented based on information in literature on unsteady-flow patterns around obstacles in the intermediate Reynolds number region. It is shown that the acceleration stage of burst swimming under restricted conditions can be treated as a frictionless impulsive motion. The stream pattern resulting from this motion is presented and the efficiency of locomotion during the acceleration stage is calculated. The flow pattern in the post-acceleration stage is sketched and the origin of an interaction between the viscous and the reactive force contribution to the propulsive force in this stage is discussed. It is explained how this interaction can lead to an increase in propulsive efficiency. A conceptual model is developed describing the three stages in burst swimming locomotion: the acceleration stage, the post-acceleration stage and the gliding stage. Data from literature of the travel distance versus time relation of the common carp larva (Cyprinus carpio) of 5.5-mm length has been used to test the model results. The test appeared remarkably successful, and the model results for larger larvae up to 22 mm length are presented. The gliding distance as a function of larval length resulting from the model has been compared with experimental data from literature. PMID:15207478

  11. An empirical conceptual gully evolution model for channelled sea cliffs

    NASA Astrophysics Data System (ADS)

    Leyland, Julian; Darby, Stephen E.

    2008-12-01

    Incised coastal channels are a specific form of incised channel that are found in locations where stream channels flowing to cliffed coasts have the excess energy required to cut down through the cliff to reach the outlet water body. The southern coast of the Isle of Wight, southern England, comprises soft cliffs that vary in height between 15 and 100 m and which are retreating at rates ≤ 1.5 m a - 1 , due to a combination of wave erosion and landslides. In several locations, river channels have cut through the cliffs to create deeply (≤ 45 m) incised gullies, known locally as 'Chines'. The Chines are unusual in that their formation is associated with dynamic shoreline encroachment during a period of rising sea-level, whereas existing models of incised channel evolution emphasise the significance of base level lowering. This paper develops a conceptual model of Chine evolution by applying space for time substitution methods using empirical data gathered from Chine channel surveys and remotely sensed data. The model identifies a sequence of evolutionary stages, which are classified based on a suite of morphometric indices and associated processes. The extent to which individual Chines are in a state of growth or decay is estimated by determining the relative rates of shoreline retreat and knickpoint recession, the former via analysis of historical aerial images and the latter through the use of a stream power erosion model.

  12. Conceptual models of the evolution of transgressive dune field systems

    NASA Astrophysics Data System (ADS)

    Hesp, Patrick A.

    2013-10-01

    This paper examines the evolutionary paths of some transgressive dune fields that have formed on different coasts of the world, and presents some initial conceptual models of system dynamics for transgressive dune sheets and dune fields. Various evolutionary pathways are conceptualized based on a visual examination of dune fields from around the world. On coasts with high sediment supply, dune sheets and dune fields tend to accumulate as large scale barrier systems with little colonization of vegetation in arid-hyper to arid climate regimes, and as multiple, active discrete phases of dune field and deflation plain couplets in temperate to tropical environments. Active dune fields tend to be singular entities on coasts with low to moderate sediment supply. Landscape complexity and vegetation richness and diversity increases as dune fields evolve from simple active sheets and dunes to single and multiple deflation plains and basins, precipitation ridges, nebkha fields and a host of other dune types associated with vegetation (e.g. trailing ridges, slacks, remnant knobs, gegenwalle ridges and dune track ridges, 'tree islands' and 'bush pockets'). Three principal scenarios of transgressive dune sheet and dune field development are discussed, including dune sheets or dune fields evolving directly from the backshore, development following foredune and/or dune field erosion, and development from the breakdown or merging of parabolic dunes. Various stages of evolution are outlined for each scenario. Knowledge of evolutionary patterns and stages in coastal dune fields is very limited and caution is urged in attempts to reverse, change and/or modify dune fields to 'restore' some perceived loss of ecosystem or dune functioning.

  13. Conceptual models of the evolution of transgressive dune field systems

    NASA Astrophysics Data System (ADS)

    A. Hesp, Patrick

    2013-10-01

    This paper examines the evolutionary paths of some transgressive dune fields that have formed on different coasts of the world, and presents some initial conceptual models of system dynamics for transgressive dune sheets and dune fields. Various evolutionary pathways are conceptualized based on a visual examination of dune fields from around the world. On coasts with high sediment supply, dune sheets and dune fields tend to accumulate as large scale barrier systems with little colonization of vegetation in arid-hyper to arid climate regimes, and as multiple, active discrete phases of dune field and deflation plain couplets in temperate to tropical environments. Active dune fields tend to be singular entities on coasts with low to moderate sediment supply. Landscape complexity and vegetation richness and diversity increases as dune fields evolve from simple active sheets and dunes to single and multiple deflation plains and basins, precipitation ridges, nebkha fields and a host of other dune types associated with vegetation (e.g. trailing ridges, slacks, remnant knobs, gegenwalle ridges and dune track ridges, ‘tree islands' and ‘bush pockets'). Three principal scenarios of transgressive dune sheet and dune field development are discussed, including dune sheets or dune fields evolving directly from the backshore, development following foredune and/or dune field erosion, and development from the breakdown or merging of parabolic dunes. Various stages of evolution are outlined for each scenario. Knowledge of evolutionary patterns and stages in coastal dune fields is very limited and caution is urged in attempts to reverse, change and/or modify dune fields to ‘restore' some perceived loss of ecosystem or dune functioning.

  14. Professional excellence and career advancement in nursing: a conceptual framework for clinical leadership development.

    PubMed

    Adeniran, Rita Kudirat; Bhattacharya, Anand; Adeniran, Anthony A

    2012-01-01

    Increasingly, stakeholders in the health care community are recognizing nursing as key to solving the nation's health care issues. This acknowledgment provides a unique opportunity for nursing to demonstrate leadership by developing clinical nurse leaders to collaborate with the multidisciplinary care team in driving evidence-based, safe quality, cost-effective health care services. One approach for nursing success is standardizing the entry-level education for nurses and developing a uniform professional development and career advancement trajectory with appropriate incentives to encourage participation. A framework to guide and provide scientific evidence of how frontline nurses can be engaged will be paramount. The model for professional excellence and career advancement provides a framework that offers a clear path for researchers to examine variables influencing nurses' professional development and career advancement in a systematic manner. Professional Excellence and Career Advancement in Nursing underscores professional preparedness of a registered nurse as central to leadership development. It also describes the elements that influence nurses' participation in professional development and career advancement under 4 main categories emphasizing mentorship and self-efficacy as essential variables.

  15. A Conceptual Model For Effluent-Dependent Riverine Environments

    NASA Astrophysics Data System (ADS)

    Murphy, M. T.; Meyerhoff, R. D.; Osterkamp, W. R.; Smith, E. L.; Hawkins, R. H.

    2001-12-01

    The Arid West Water Quality Research Project (WQRP) is a multi-year, EPA-funded scientific endeavor directed by the Pima County, Wastewater Management Department in southern Arizona and focussed upon several interconnected ecological questions. These questions are crucial to water quality management in the arid and semi arid western US. A key component has been the ecological, hydrological and geomorphological investigation of habitat created by the discharge of treated effluent into ephemeral streams. Such environments are fundamentally different from the dry streams or rivers they displace; however, they are clearly not the perennial streams they superficially resemble. Under Arizona State regulations, such streams can bear the use designation of "Effluent Dependent Waters," or EDWs. Before this investigation, a hydrological/ecological conceptual model for these unique ecosystems had not been published. We have constructed one for general review that is designed to direct future work in the WQRP. The project investigated ten representative, yet contrasting EDW sites distributed throughout arid areas of the western US, to gather both historical and reconnaissance level field data, including in-stream and riparian, habitat and morphometric fluvial data. In most cases, the cross sectional area of the prior channel is oversized relative to the discharge of the introduced effluent. Where bed control is absent, the channels are incised downstream of the discharge point, further suggesting a disequilibrium between the channel and the regulated effluent flow. Several of the studied stream systems primarily convey storm water and are aggradational, exhibiting braided or anastomizing channels, high energy bedforms, and spatially dynamic interfluves. Active channels are formed in response to individual storm events and can be highly dynamic in both location and cross-sectional morphology. This poses a geomorphological challenge in the selection of a discharge point. We

  16. The conceptual approach to quantitative modeling of guard cells.

    PubMed

    Blatt, Michael R; Hills, Adrian; Chen, Zhong-Hua; Wang, Yizhou; Papanatsiou, Maria; Lew, Vigilio L

    2013-01-01

    Much of the 70% of global water usage associated with agriculture passes through stomatal pores of plant leaves. The guard cells, which regulate these pores, thus have a profound influence on photosynthetic carbon assimilation and water use efficiency of plants. We recently demonstrated how quantitative mathematical modeling of guard cells with the OnGuard modeling software yields detail sufficient to guide phenotypic and mutational analysis. This advance represents an all-important step toward applications in directing "reverse-engineering" of guard cell function for improved water use efficiency and carbon assimilation. OnGuard is nonetheless challenging for those unfamiliar with a modeler's way of thinking. In practice, each model construct represents a hypothesis under test, to be discarded, validated or refined by comparisons between model predictions and experimental results. The few guidelines set out here summarize the standard and logical starting points for users of the OnGuard software.

  17. Towards methodical modelling: Differences between the structure and output dynamics of multiple conceptual models

    NASA Astrophysics Data System (ADS)

    Knoben, Wouter; Woods, Ross; Freer, Jim

    2016-04-01

    Conceptual hydrologic models consist of a certain arrangement of spatial and temporal dynamics consisting of stores, fluxes and transformation functions, depending on the modeller's choices and intended use. They have the advantages of being computationally efficient, being relatively easy model structures to reconfigure and having relatively low input data demands. This makes them well-suited for large-scale and large-sample hydrology, where appropriately representing the dominant hydrologic functions of a catchment is a main concern. Given these requirements, the number of parameters in the model cannot be too high, to avoid equifinality and identifiability issues. This limits the number and level of complexity of dominant hydrologic processes the model can represent. Specific purposes and places thus require a specific model and this has led to an abundance of conceptual hydrologic models. No structured overview of these models exists and there is no clear method to select appropriate model structures for different catchments. This study is a first step towards creating an overview of the elements that make up conceptual models, which may later assist a modeller in finding an appropriate model structure for a given catchment. To this end, this study brings together over 30 past and present conceptual models. The reviewed model structures are simply different configurations of three basic model elements (stores, fluxes and transformation functions), depending on the hydrologic processes the models are intended to represent. Differences also exist in the inner workings of the stores, fluxes and transformations, i.e. the mathematical formulations that describe each model element's intended behaviour. We investigate the hypothesis that different model structures can produce similar behavioural simulations. This can clarify the overview of model elements by grouping elements which are similar, which can improve model structure selection.

  18. Computational Plume Modeling of COnceptual ARES Vehicle Stage Tests

    NASA Technical Reports Server (NTRS)

    Allgood, Daniel C.; Ahuja, Vineet

    2007-01-01

    The plume-induced environment of a conceptual ARES V vehicle stage test at the NASA Stennis Space Center (NASA-SSC) was modeled using computational fluid dynamics (CFD). A full-scale multi-element grid was generated for the NASA-SSC B-2 test stand with the ARES V stage being located in a proposed off-center forward position. The plume produced by the ARES V main power plant (cluster of five RS-68 LOX/LH2 engines) was simulated using a multi-element flow solver - CRUNCH. The primary objective of this work was to obtain a fundamental understanding of the ARES V plume and its impingement characteristics on the B-2 flame-deflector. The location, size and shape of the impingement region were quantified along with the un-cooled deflector wall pressures, temperatures and incident heating rates. Issues with the proposed tests were identified and several of these addressed using the CFD methodology. The final results of this modeling effort will provide useful data and boundary conditions in upcoming engineering studies that are directed towards determining the required facility modifications for ensuring safe and reliable stage testing in support of the Constellation Program.

  19. Addressing Conceptual Model Uncertainty in the Evaluation of Model Prediction Errors

    NASA Astrophysics Data System (ADS)

    Carrera, J.; Pool, M.

    2014-12-01

    Model predictions are uncertain because of errors in model parameters, future forcing terms, and model concepts. The latter remain the largest and most difficult to assess source of uncertainty in long term model predictions. We first review existing methods to evaluate conceptual model uncertainty. We argue that they are highly sensitive to the ingenuity of the modeler, in the sense that they rely on the modeler's ability to propose alternative model concepts. Worse, we find that the standard practice of stochastic methods leads to poor, potentially biased and often too optimistic, estimation of actual model errors. This is bad news because stochastic methods are purported to properly represent uncertainty. We contend that the problem does not lie on the stochastic approach itself, but on the way it is applied. Specifically, stochastic inversion methodologies, which demand quantitative information, tend to ignore geological understanding, which is conceptually rich. We illustrate some of these problems with the application to Mar del Plata aquifer, where extensive data are available for nearly a century. Geologically based models, where spatial variability is handled through zonation, yield calibration fits similar to geostatiscally based models, but much better predictions. In fact, the appearance of the stochastic T fields is similar to the geologically based models only in areas with high density of data. We take this finding to illustrate the ability of stochastic models to accommodate many data, but also, ironically, their inability to address conceptual model uncertainty. In fact, stochastic model realizations tend to be too close to the "most likely" one (i.e., they do not really realize the full conceptualuncertainty). The second part of the presentation is devoted to argue that acknowledging model uncertainty may lead to qualitatively different decisions than just working with "most likely" model predictions. Therefore, efforts should concentrate on

  20. Development of Conceptual Benchmark Models to Evaluate Complex Hydrologic Model Calibration in Managed Basins Using Python

    NASA Astrophysics Data System (ADS)

    Hughes, J. D.; White, J.

    2013-12-01

    For many numerical hydrologic models it is a challenge to quantitatively demonstrate that complex models are preferable to simpler models. Typically, a decision is made to develop and calibrate a complex model at the beginning of a study. The value of selecting a complex model over simpler models is commonly inferred from use of a model with fewer simplifications of the governing equations because it can be time consuming to develop another numerical code with data processing and parameter estimation functionality. High-level programming languages like Python can greatly reduce the effort required to develop and calibrate simple models that can be used to quantitatively demonstrate the increased value of a complex model. We have developed and calibrated a spatially-distributed surface-water/groundwater flow model for managed basins in southeast Florida, USA, to (1) evaluate the effect of municipal groundwater pumpage on surface-water/groundwater exchange, (2) investigate how the study area will respond to sea-level rise, and (3) explore combinations of these forcing functions. To demonstrate the increased value of this complex model, we developed a two-parameter conceptual-benchmark-discharge model for each basin in the study area. The conceptual-benchmark-discharge model includes seasonal scaling and lag parameters and is driven by basin rainfall. The conceptual-benchmark-discharge models were developed in the Python programming language and used weekly rainfall data. Calibration was implemented with the Broyden-Fletcher-Goldfarb-Shanno method available in the Scientific Python (SciPy) library. Normalized benchmark efficiencies calculated using output from the complex model and the corresponding conceptual-benchmark-discharge model indicate that the complex model has more explanatory power than the simple model driven only by rainfall.

  1. Advanced Modeling of Micromirror Devices

    NASA Technical Reports Server (NTRS)

    Michalicek, M. Adrian; Sene, Darren E.; Bright, Victor M.

    1995-01-01

    The flexure-beam micromirror device (FBMD) is a phase only piston style spatial light modulator demonstrating properties which can be used for phase adaptive corrective optics. This paper presents a complete study of a square FBMD, from advanced model development through final device testing and model verification. The model relates the electrical and mechanical properties of the device by equating the electrostatic force of a parallel-plate capacitor with the counter-acting spring force of the device's support flexures. The capacitor solution is derived via the Schwartz-Christoffel transformation such that the final solution accounts for non-ideal electric fields. The complete model describes the behavior of any piston-style device, given its design geometry and material properties. It includes operational parameters such as drive frequency and temperature, as well as fringing effects, mirror surface deformations, and cross-talk from neighboring devices. The steps taken to develop this model can be applied to other micromirrors, such as the cantilever and torsion-beam designs, to produce an advanced model for any given device. The micromirror devices studied in this paper were commercially fabricated in a surface micromachining process. A microscope-based laser interferometer is used to test the device in which a beam reflected from the device modulates a fixed reference beam. The mirror displacement is determined from the relative phase which generates a continuous set of data for each selected position on the mirror surface. Plots of this data describe the localized deflection as a function of drive voltage.

  2. Semantic Description of Educational Adaptive Hypermedia Based on a Conceptual Model

    ERIC Educational Resources Information Center

    Papasalouros, Andreas; Retalis, Symeon; Papaspyrou, Nikolaos

    2004-01-01

    The role of conceptual modeling in Educational Adaptive Hypermedia Applications (EAHA) is especially important. A conceptual model of an educational application depicts the instructional solution that is implemented, containing information about concepts that must be ac-quired by learners, tasks in which learners must be involved and resources…

  3. A Conceptual Model of Pain Assessment for Noncommunicative Persons with Dementia

    ERIC Educational Resources Information Center

    Snow, A. Lynn; O'Malley, Kimberly J.; Cody, Marisue; Kunik, Mark E.; Ashton, Carol M.; Beck, Cornelia; Bruera, Eduardo; Novy, Diane

    2004-01-01

    Purpose: Our objectives are to present a conceptual model of the pain assessment process in persons with dementia and discuss methods for validating our model within this population. Design and Methods: This conceptual work is based on an integrative review and current pain theory, pain assessment research in demented and nondemented populations,…

  4. The Value of Conceptual Models in Coping with Complexity and Interdisciplinarity in Environmental Sciences Education

    ERIC Educational Resources Information Center

    Fortuin, Karen P. J.; van Koppen, C. S. A.; Leemans, Rik

    2011-01-01

    Conceptual models are useful for facing the challenges of environmental sciences curriculum and course developers and students. These challenges are inherent to the interdisciplinary and problem-oriented character of environmental sciences curricula. In this article, we review the merits of conceptual models in facing these challenges. These…

  5. Teacher Emotion Research: Introducing a Conceptual Model to Guide Future Research

    ERIC Educational Resources Information Center

    Fried, Leanne; Mansfield, Caroline; Dobozy, Eva

    2015-01-01

    This article reports on the development of a conceptual model of teacher emotion through a review of teacher emotion research published between 2003 and 2013. By examining 82 publications regarding teacher emotion, the main aim of the review was to identify how teacher emotion was conceptualised in the literature and develop a conceptual model to…

  6. Advanced Mirror & Modelling Technology Development

    NASA Technical Reports Server (NTRS)

    Effinger, Michael; Stahl, H. Philip; Abplanalp, Laura; Maffett, Steven; Egerman, Robert; Eng, Ron; Arnold, William; Mosier, Gary; Blaurock, Carl

    2014-01-01

    The 2020 Decadal technology survey is starting in 2018. Technology on the shelf at that time will help guide selection to future low risk and low cost missions. The Advanced Mirror Technology Development (AMTD) team has identified development priorities based on science goals and engineering requirements for Ultraviolet Optical near-Infrared (UVOIR) missions in order to contribute to the selection process. One key development identified was lightweight mirror fabrication and testing. A monolithic, stacked, deep core mirror was fused and replicated twice to achieve the desired radius of curvature. It was subsequently successfully polished and tested. A recently awarded second phase to the AMTD project will develop larger mirrors to demonstrate the lateral scaling of the deep core mirror technology. Another key development was rapid modeling for the mirror. One model focused on generating optical and structural model results in minutes instead of months. Many variables could be accounted for regarding the core, face plate and back structure details. A portion of a spacecraft model was also developed. The spacecraft model incorporated direct integration to transform optical path difference to Point Spread Function (PSF) and between PSF to modulation transfer function. The second phase to the project will take the results of the rapid mirror modeler and integrate them into the rapid spacecraft modeler.

  7. A revised conceptual model of the tropical marine boundary layer

    NASA Astrophysics Data System (ADS)

    Davison, Jennifer L.

    on days with higher rain rates, and more (fewer) layers tended to be present when surface winds were more southerly (northerly). BSL statistics serve as the basis for a revised conceptual model of the TMBL, which contains 2-3 more layers of enhanced static stability, layered structure to the moisture variability and extends more than a km higher than the previous conceptual model. When compared, the distribution curves as functions of altitude for 1) BSL tops and 2) satellite derived cloud top heights had a correlation coefficient of 0.92, lending satellite support to the radar portrayal of the TMBL. Frequency by altitude diagrams (FADs) of rawinsonde data showed that the TMBL was sufficiently turbulent to support the Bragg scattering. RH gradients across 350 m intervals ranged from changes of greater than 95% to less than -60%, and all values of RH had a nearly equal probability of occurrence between 2 and 4 km. There were no preferred heights for temperature inversions, with inversions found across both 50 m and 350 m intervals for all altitudes above 1.2 km. The FAD of equivalent potential temperature indicated that the air modified by the ocean typically extended up to 4 km. Disturbed days (e.g., those with rain rates > 2 mm day-1) tended to be moister---with the moisture extending higher, than undisturbed days. The disturbed days also tended to be cooler between 2 and 4.5 km and have less northerly winds in the lowest 4 km.

  8. Spiritual Healing in the Aftermath of Childhood Maltreatment: Translating Men's Lived Experiences Utilizing Nursing Conceptual Models and Theory.

    PubMed

    Willis, Danny G; DeSanto-Madeya, Susan; Ross, Richard; Sheehan, Danielle Leone; Fawcett, Jacqueline

    2015-01-01

    This article presents an explication of spiritual healing situated within 3 nursing conceptual models (Neuman's systems model, Rogers' science of unitary human beings, and Roy's adaptation model) and 1 middle-range theory (Watson's theory of human caring), all of which include a focus on spirituality. These models and the theory are the vehicle for translation of themes of spiritual healing extracted from data provided by 30 adult male survivors of childhood maltreatment into nursing practice. This discipline-specific translational scholarship advances the profession of nursing.

  9. 7-GeV advanced photon source beamline initiative: Conceptual design report

    SciTech Connect

    Not Available

    1993-05-01

    The DOE is building a new generation 6-7 GeV Synchrotron Radiation Source known as the Advanced Photon Source (APS) at Argonne National Laboratory. This facility, to be completed in FY 1996, can provide 70 x-ray sources of unprecedented brightness to meet the research needs of virtually all scientific disciplines and numerous technologies. The technological research capability of the APS in the areas of energy, communications and health will enable a new partnership between the DOE and US industry. Current funding for the APS will complete the current phase of construction so that scientists can begin their applications in FY 1996. Comprehensive utilization of the unique properties of APS beams will enable cutting-edge research not currently possible. It is now appropriate to plan to construct additional radiation sources and beamline standard components to meet the excess demands of the APS users. In this APS Beamline Initiative, 2.5-m-long insertion-device x-ray sources will be built on four straight sections of the APS storage ring, and an additional four bending-magnet sources will also be put in use. The front ends for these eight x-ray sources will be built to contain and safeguard access to these bright x-ray beams. In addition, funds will be provided to build standard beamline components to meet scientific and technological research demands of the Collaborative Access Teams. The Conceptual Design Report (CDR) for the APS Beamline Initiative describes the scope of all the above technical and conventional construction and provides a detailed cost and schedule for these activities. The document also describes the preconstruction R&D plans for the Beamline Initiative activities and provides the cost estimates for the required R&D.

  10. Modeling Tool Advances Rotorcraft Design

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Continuum Dynamics Inc. (CDI), founded in 1979, specializes in advanced engineering services, including fluid dynamic modeling and analysis for aeronautics research. The company has completed a number of SBIR research projects with NASA, including early rotorcraft work done through Langley Research Center, but more recently, out of Ames Research Center. NASA Small Business Innovation Research (SBIR) grants on helicopter wake modeling resulted in the Comprehensive Hierarchical Aeromechanics Rotorcraft Model (CHARM), a tool for studying helicopter and tiltrotor unsteady free wake modeling, including distributed and integrated loads, and performance prediction. Application of the software code in a blade redesign program for Carson Helicopters, of Perkasie, Pennsylvania, increased the payload and cruise speeds of its S-61 helicopter. Follow-on development resulted in a $24 million revenue increase for Sikorsky Aircraft Corporation, of Stratford, Connecticut, as part of the company's rotor design efforts. Now under continuous development for more than 25 years, CHARM models the complete aerodynamics and dynamics of rotorcraft in general flight conditions. CHARM has been used to model a broad spectrum of rotorcraft attributes, including performance, blade loading, blade-vortex interaction noise, air flow fields, and hub loads. The highly accurate software is currently in use by all major rotorcraft manufacturers, NASA, the U.S. Army, and the U.S. Navy.

  11. Development of a conceptual model for vertical flow wetland metabolism.

    PubMed

    Giraldo, E; Zárate, E

    2001-01-01

    Four parallel vertical constructed wetlands, with a total area of 556 m2, are used to treat domestic wastewater, coming from a community of 550 inhabitants. The system includes pre-treatment with an anaerobic filter and post-treatment with chlorine, before discharging the effluent to the ocean. Four native species of macrophytes were planted: Paspalum penisetum, Typha sp, Conocarpres erectus and Scirpus lacustris. In situ measurements of gas content were performed for each bed during an operation cycle. After a feeding discharge, an unaltered sample of sand from each bed was taken, and a respirometric test was implemented to measure the metabolic activity in terms of oxygen consumption kinetics, CO2 production and organic matter degradation. The results were used to develop a conceptual model of the microbiologic metabolism for the process of organic matter removal from wastewater. Sorption in the bed is the main mechanism for organic matter removal from the wastewater, with subsequent biological oxidation during the resting period. The degradation rate for dissolved organic matter is found to be dependent on its concentration and on oxygen content in the gaseous phase. During the days of major activity, the oxygen content was not fully recovered when a new discharge occurred, finding anaerobic activity within the bed.

  12. Development of a conceptual model for vertical flow wetland metabolism.

    PubMed

    Giraldo, E; Zárate, E

    2001-01-01

    Four parallel vertical constructed wetlands, with a total area of 556 m2, are used to treat domestic wastewater, coming from a community of 550 inhabitants. The system includes pre-treatment with an anaerobic filter and post-treatment with chlorine, before discharging the effluent to the ocean. Four native species of macrophytes were planted: Paspalum penisetum, Typha sp, Conocarpres erectus and Scirpus lacustris. In situ measurements of gas content were performed for each bed during an operation cycle. After a feeding discharge, an unaltered sample of sand from each bed was taken, and a respirometric test was implemented to measure the metabolic activity in terms of oxygen consumption kinetics, CO2 production and organic matter degradation. The results were used to develop a conceptual model of the microbiologic metabolism for the process of organic matter removal from wastewater. Sorption in the bed is the main mechanism for organic matter removal from the wastewater, with subsequent biological oxidation during the resting period. The degradation rate for dissolved organic matter is found to be dependent on its concentration and on oxygen content in the gaseous phase. During the days of major activity, the oxygen content was not fully recovered when a new discharge occurred, finding anaerobic activity within the bed. PMID:11804107

  13. Conceptual hydrogeological model of a coastal hydrosystem in the mediterranean

    NASA Astrophysics Data System (ADS)

    Mitropapas, Anastasios; Pouliaris, Christos; Apostolopoulos, Georgios; Vasileiou, Eleni; Schüth, Christoph; Vienken, Thomas; Dietrich, Peter; Kallioras, Andreas

    2016-04-01

    Groundwater resources management in the Mediterranean basin is an issue of paramount importance that becomes a necessity in the case of the coastal hydrosystems. Coastal aquifers are considered very sensitive ecosystems that are subject to several stresses being of natural or anthropogenic origin. The coastal hydrosystem of Lavrion can be used as a reference site that incorporates multi-disciplinary environmental problems, which are typical for Circum-Mediterranean. This study presents the synthesis of a wide range of field activities within the area of Lavrion including the monitoring of water resources within all hydrologic zones (surface, unsaturated and saturated) and geophysical (invasive and non-invasive) surveys. Different monitoring approaches -targeting to the collection of hydrochemical, geophysical, geological, hydrological data- were applied, that proved to provide a sound characterization of the groundwater flows within the coastal karstic system in connection to the surrounding water bodies of the study area. The above are used as input parameters process during the development of the conceptual model of the coastal hydrosystem of Lavrion. Key-words: Coastal hydrosystems, Mediterranean basin, seawater intrusion

  14. Initial Conceptualization and Application of the Alaska Thermokarst Model

    NASA Astrophysics Data System (ADS)

    Bolton, W. R.; Lara, M. J.; Genet, H.; Romanovsky, V. E.; McGuire, A. D.

    2015-12-01

    Thermokarst topography forms whenever ice-rich permafrost thaws and the ground subsides due to the volume loss when ground ice transitions to water. The Alaska Thermokarst Model (ATM) is a large-scale, state-and-transition model designed to simulate transitions between landscape units affected by thermokarst disturbance. The ATM uses a frame-based methodology to track transitions and proportion of cohorts within a 1-km2 grid cell. In the arctic tundra environment, the ATM tracks thermokarst-related transitions among wetland tundra, graminoid tundra, shrub tundra, and thermokarst lakes. In the boreal forest environment, the ATM tracks transitions among forested permafrost plateau, thermokarst lakes, collapse scar fens and bogs. The transition from one cohort to another due to thermokarst processes can take place if thaw reaches ice-rich ground layers either due to pulse disturbance (i.e. large precipitation event or fires), or due to gradual active layer deepening that eventually results in penetration of the protective layer. The protective layer buffers the ice-rich soils from the land surface and is critical to determine how susceptible an area is to thermokarst degradation. The rate of terrain transition in our model is determined by a set of rules that are based upon the ice-content of the soil, the drainage efficiency (or the ability of the landscape to store or transport water), the cumulative probability of thermokarst initiation, distance from rivers, lake dynamics (increasing, decreasing, or stable), and other factors. Tundra types are allowed to transition from one type to another (for example, wetland tundra to graminoid tundra) under favorable climatic conditions. In this study, we present our conceptualization and initial simulation results from in the arctic (the Barrow Peninsula) and boreal (the Tanana Flats) regions of Alaska.

  15. Health psychology as a context for massage therapy: a conceptual model with CAM as mediator.

    PubMed

    Hymel, Glenn M; Rich, Grant J

    2014-04-01

    Health psychology represents a context within which massage therapy research, education, and practice can be positioned for the mutual benefit of both. Furthermore, complementary and alternative medicine (CAM) more often than not plays a mediating role in relating massage therapy to health psychology. On occasion, though, the linkage between health psychology and massage therapy can be quite direct without the mediating influence of CAM. This paper, accordingly, advances a conceptual model via both flowchart and Venn diagram displays for viewing the health psychology context for massage therapy with the possibility of CAM as a mediating factor. Attention is also given to the broad range of issues constituting contemporary health psychology as well as its correspondence to an equally diverse array of client populations and health conditions addressed in massage therapy research. Future directions in the areas of health psychology, CAM, and massage therapy are proposed with a view toward a mutual and reciprocal benefit accruing to these behavioral and health science arenas.

  16. Using the conceptual site model approach to characterize groundwater quality

    SciTech Connect

    Shephard, E.; Glucksberg, N.; Walter, N.

    2007-07-01

    To understand groundwater quality, the first step is to develop a conceptual site model (CSM) that describes the site history, describes the geology and the hydrogeology of the site, identifies potential release areas or sources, and evaluates the fate and transport of site related compounds. After the physical site setting is understood and potential release areas are identified, appropriate and representative groundwater monitoring wells may be used to evaluate groundwater quality at a site and provide a network to assess impacts from potential future releases. To develop the CSM, the first step to understand the different requirements from each of the regulatory stakeholders. Each regulatory agency may have different approaches to site characterization and closure (i.e., different groundwater and soil remediation criteria). For example, the United States Environmental Protection Agency (EPA) and state governments have published guidance documents that proscribe the required steps and information needed to develop a CSM. The Nuclear Regulatory Commission (NRC) has a proscriptive model for the Historical Site Assessment under the Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM), and contains requirements for developing a conceptual site model in NUREG 1757. Federal and state agencies may also have different closure criteria for potential contaminants of concern. Understanding these differences before starting a groundwater monitoring program is important because the minimum detectable activity (MDA), lowest limit detection (LLD), and sample quantitation limit (SQL) must be low enough so that data may be evaluated under each of the programs. After a Historical Site Assessment is completed a work plan is developed and executed to not only collect physical data that describes the geology and hydrogeology, but to also characterize the soil, groundwater, sediments, and surface water quality of each potentially impacted areas. Although the primary

  17. Conceptual Model of Water Resources in the Kabul Basin, Afghanistan

    USGS Publications Warehouse

    Mack, Thomas J.; Akbari, M. Amin; Ashoor, M. Hanif; Chornack, Michael P.; Coplen, Tyler B.; Emerson, Douglas G.; Hubbard, Bernard E.; Litke, David W.; Michel, Robert L.; Plummer, L. Niel; Rezai, M. Taher; Senay, Gabriel B.; Verdin, James P.; Verstraeten, Ingrid M.

    2010-01-01

    The United States (U.S.) Geological Survey has been working with the Afghanistan Geological Survey and the Afghanistan Ministry of Energy and Water on water-resources investigations in the Kabul Basin under an agreement supported by the United States Agency for International Development. This collaborative investigation compiled, to the extent possible in a war-stricken country, a varied hydrogeologic data set and developed limited data-collection networks to assist with the management of water resources in the Kabul Basin. This report presents the results of a multidisciplinary water-resources assessment conducted between 2005 and 2007 to address questions of future water availability for a growing population and of the potential effects of climate change. Most hydrologic and climatic data-collection activities in Afghanistan were interrupted in the early 1980s as a consequence of war and civil strife and did not resume until 2003 or later. Because of the gap of more than 20 years in the record of hydrologic and climatic observations, this investigation has made considerable use of remotely sensed data and, where available, historical records to investigate the water resources of the Kabul Basin. Specifically, this investigation integrated recently acquired remotely sensed data and satellite imagery, including glacier and climatic data; recent climate-change analyses; recent geologic investigations; analysis of streamflow data; groundwater-level analysis; surface-water- and groundwater-quality data, including data on chemical and isotopic environmental tracers; and estimates of public-supply and agricultural water uses. The data and analyses were integrated by using a simplified groundwater-flow model to test the conceptual model of the hydrologic system and to assess current (2007) and future (2057) water availability. Recharge in the basin is spatially and temporally variable and generally occurs near streams and irrigated areas in the late winter and early

  18. ITE CHARACTERIZATION TO SUPPORT CONCEPTUAL MODEL DEVELOPMENT FOR SUBSURFACE RADIONUCLIDE TRANSPORT

    EPA Science Inventory

    Remediation of radionuclide contaminants in ground water often begins with the development of conceptual and analytical models that guide our understanding of the processes controlling radionuclide transport. The reliability of these models is often predicated on the collection o...

  19. Improving Conceptual Models Using AEM Data and Probability Distributions

    NASA Astrophysics Data System (ADS)

    Davis, A. C.; Munday, T. J.; Christensen, N. B.

    2012-12-01

    main diagonal is used. Complications arise when we ask more specific questions, such as "What is the probability that the resistivity of layer 2 <= x, given that layer 1 <= y?" The probability then becomes conditional, calculation includes covariance terms, the integration is taken over many dimensions, and the cross-correlation of parameters becomes important. To illustrate, we examine the inversion results of a Tempest AEM survey over the Uley Basin aquifers in the Eyre Peninsula, South Australia. Key aquifers include the unconfined Bridgewater Formation that overlies the Uley and Wanilla Formations, which contain Tertiary clays and Tertiary sandstone. These Formations overlie weathered basement which define the lower bound of the Uley Basin aquifer systems. By correlating the conductivity of the sub-surface Formation types, we pose questions such as: "What is the probability-depth of the Bridgewater Formation in the Uley South Basin?", "What is the thickness of the Uley Formation?" and "What is the most probable depth to basement?" We use these questions to generate improved conceptual hydrogeological models of the Uley Basin in order to develop better estimates of aquifer extent and the available groundwater resource.

  20. Implementing Clickers to Assist Learning in Science Lectures: The Clicker-Assisted Conceptual Change Model

    ERIC Educational Resources Information Center

    Lin, Yi-Chun; Liu, Tzu-Chien; Chu, Ching-Chi

    2011-01-01

    The purposes of this study were twofold. The first aim was to design and develop a clicker-based instructional model known as "Clicker-Assisted Conceptual Change" (CACC), based on the cognitive conflict approach for conceptual change, to help students to learn scientific concepts. The second aim was to determine the beneficial effects of CACC on…

  1. Navigating Tensions between Conceptual and Metaconceptual Goals in the Use of Models

    ERIC Educational Resources Information Center

    Delgado, Cesar

    2015-01-01

    Science education involves learning about phenomena at three levels: concrete (facts and generalizations), conceptual (concepts and theories), and metaconceptual (epistemology) (Snir et al. in "J Sci Educ Technol" 2(2):373-388, 1993). Models are key components in science, can help build conceptual understanding, and may also build…

  2. Applying a Cognitive-Affective Model of Conceptual Change to Professional Development

    ERIC Educational Resources Information Center

    Ebert, Ellen K.; Crippen, Kent J.

    2010-01-01

    This study evaluated Gregoire's (2003) Cognitive-Affective Conceptual Change model (CAMCC) for predicting and assessing conceptual change in science teachers engaged in a long-term professional development project set in a large school district in the southwestern United States. A multiple case study method with data from three teacher…

  3. A Scoping Review: Conceptualizations and Pedagogical Models of Learning in Nursing Simulation

    ERIC Educational Resources Information Center

    Poikela, Paula; Teräs, Marianne

    2015-01-01

    Simulations have been implemented globally in nursing education for years with diverse conceptual foundations. The aim of this scoping review is to examine the literature regarding the conceptualizations of learning and pedagogical models in nursing simulations. A scoping review of peer-reviewed articles published between 2000 and 2013 was…

  4. Conceptual Models of the Potentiometric Surface at Yucca Mountain, NV

    NASA Astrophysics Data System (ADS)

    Hill, M.; Winterle, J.; Farrell, D.; Sims, D.; Bertetti, P.

    2002-05-01

    The U.S. Department of Energy (DOE) is evaluating Yucca Mountain (YM) Nevada, as the potential site for geologic disposal of high-level nuclear waste (HLW). If approved, the repository would be located approximately 244 to 305 m (800-1,000 ft) above the present water table. Total-system performance assessments that consider both engineered and geologic barrier systems are one method used to evaluate whether the potential repository can meet regulatory requirements. Flow paths interpreted from the potentiometric surface in the saturated zone beneath YM are incorporated into the performance assessment codes. Therefore, it is important that our understanding of the potentiometric surface is sufficient to assess potential repository performance. The addition of new water-level data from the Nye County Early Warning Drilling Program (EWDP) has helped constrain the conceptual model of the site-scale potentiometric surface at YM, specifically in the southern portion of the site along U.S. Highway 95. The EWDP was initiated in 1998, with the purpose of identifying the flow paths for contaminants should they egress from the proposed repository into the groundwater system. A revised site-scale potentiometric surface map for YM utilizing the new water-level data obtained from the EWDP is presented. The revised site-scale potentiometric surface map and other existing site-scale potentiometric surface maps interpreted from water-level data, are compared to structural, geophysical, and chemical data to evaluate whether consensus exists among the different data types concerning groundwater flow at YM. This abstract documents work performed in part by the Center for Nuclear Waste Regulatory Analyses under contract No. NRC-02-97-009. The report is an independent product and does not reflect the regulatory position of the NRC.

  5. Identifying Students' Mental Models of Sound Propagation: The Role of Conceptual Blending in Understanding Conceptual Change

    ERIC Educational Resources Information Center

    Hrepic, Zdeslav; Zollman, Dean A.; Rebello, N. Sanjay

    2010-01-01

    We investigated introductory physics students' mental models of sound propagation. We used a phenomenographic method to analyze the data in the study. In addition to the scientifically accepted Wave model, students used the "Entity" model to describe the propagation of sound. In this latter model sound is a self-standing entity, different from the…

  6. A conceptual modeling framework for discrete event simulation using hierarchical control structures

    PubMed Central

    Furian, N.; O’Sullivan, M.; Walker, C.; Vössner, S.; Neubacher, D.

    2015-01-01

    Conceptual Modeling (CM) is a fundamental step in a simulation project. Nevertheless, it is only recently that structured approaches towards the definition and formulation of conceptual models have gained importance in the Discrete Event Simulation (DES) community. As a consequence, frameworks and guidelines for applying CM to DES have emerged and discussion of CM for DES is increasing. However, both the organization of model-components and the identification of behavior and system control from standard CM approaches have shortcomings that limit CM’s applicability to DES. Therefore, we discuss the different aspects of previous CM frameworks and identify their limitations. Further, we present the Hierarchical Control Conceptual Modeling framework that pays more attention to the identification of a models’ system behavior, control policies and dispatching routines and their structured representation within a conceptual model. The framework guides the user step-by-step through the modeling process and is illustrated by a worked example. PMID:26778940

  7. A Conceptual Aerospace Vehicle Structural System Modeling, Analysis and Design Process

    NASA Technical Reports Server (NTRS)

    Mukhopadhyay, Vivek

    2007-01-01

    A process for aerospace structural concept analysis and design is presented, with examples of a blended-wing-body fuselage, a multi-bubble fuselage concept, a notional crew exploration vehicle, and a high altitude long endurance aircraft. Aerospace vehicle structures must withstand all anticipated mission loads, yet must be designed to have optimal structural weight with the required safety margins. For a viable systems study of advanced concepts, these conflicting requirements must be imposed and analyzed early in the conceptual design cycle, preferably with a high degree of fidelity. In this design process, integrated multidisciplinary analysis tools are used in a collaborative engineering environment. First, parametric solid and surface models including the internal structural layout are developed for detailed finite element analyses. Multiple design scenarios are generated for analyzing several structural configurations and material alternatives. The structural stress, deflection, strain, and margins of safety distributions are visualized and the design is improved. Over several design cycles, the refined vehicle parts and assembly models are generated. The accumulated design data is used for the structural mass comparison and concept ranking. The present application focus on the blended-wing-body vehicle structure and advanced composite material are also discussed.

  8. Using Multilevel Modeling in Language Assessment Research: A Conceptual Introduction

    ERIC Educational Resources Information Center

    Barkaoui, Khaled

    2013-01-01

    This article critiques traditional single-level statistical approaches (e.g., multiple regression analysis) to examining relationships between language test scores and variables in the assessment setting. It highlights the conceptual, methodological, and statistical problems associated with these techniques in dealing with multilevel or nested…

  9. Mapping the Territory: A Conceptual Model of Scholastic Journalism.

    ERIC Educational Resources Information Center

    Arnold, Mary

    Intended to provide a comprehensive conceptual framework to serve as a scaffold for past, present, and future research on "scholastic journalism" (journalism in the secondary school), a topical content analysis of the Association for Education in Journalism and Mass Communication (AEJMC) Secondary Education Division research, teaching, and issues…

  10. Adapting Conceptual Models for Cross-Cultural Applications

    ERIC Educational Resources Information Center

    Perleth, Christoph; Heller, Kurt A.

    2007-01-01

    It is of major importance to use psychological tests and questionnaires that are carefully constructed so that their reliability and validity can be determined in different (sub)cultures (Campbell & Tirri, 2004). However, a necessary prerequisite for this is the development of solid conceptual constructs. Otherwise, the researcher runs into the…

  11. Collective (Team) Learning Process Models: A Conceptual Review

    ERIC Educational Resources Information Center

    Knapp, Randall

    2010-01-01

    Teams have become a key resource for learning and accomplishing work in organizations. The development of collective learning in specific contexts is not well understood, yet has become critical to organizational success. The purpose of this conceptual review is to inform human resource development (HRD) practice about specific team behaviors and…

  12. Psychological Mechanisms of Medically Unexplained Symptoms: An Integrative Conceptual Model

    ERIC Educational Resources Information Center

    Brown, Richard J.

    2004-01-01

    Theories of medically unexplained illness based on the concepts of dissociation, conversion, and somatization are summarized. Evidence cited in support of these theories is described and the conceptual strengths and shortcomings of each approach are considered. It is argued that each of these approaches adds to the understanding of unexplained…

  13. Experimental Evidence of the Superiority of the Prevalence Model of Conceptual Change over the Classical Models and Repetition

    ERIC Educational Resources Information Center

    Potvin, Patrice; Sauriol, Érik; Riopel, Martin

    2015-01-01

    This quasi-experimental study investigated the effects on 558 grades five and six students of three different teaching conditions: the "classical" model of conceptual change (for which cognitive conflict is considered as a precondition to the transformation of knowledge), the "prevalence" model of conceptual change (in which…

  14. How to conceptualize catalytic cycles? The energetic span model.

    PubMed

    Kozuch, Sebastian; Shaik, Sason

    2011-02-15

    efficiency of a catalyst. Additionally, the TDI and TDTS are not necessarily the highest and lowest states, nor do they have to be adjoined as a single step. As such, we can conclude that a change in the conceptualization of catalytic cycles is in order: in catalysis, there are no rate-determining steps, but rather rate-determining states. We also include a study on the effect of reactant and product concentrations. In the energetic span approximation, only the reactants or products that are located between the TDI and TDTS accelerate or inhibit the reaction. In this manner, the energetic span model creates a direct link between experimental quantities and theoretical results. The versatility of the energetic span model is demonstrated with several catalytic cycles of organometallic reactions.

  15. Conceptual geologic model and native state model of the Roosevelt Hot Springs hydrothermal system

    SciTech Connect

    Faulder, D.D.

    1991-01-01

    A conceptual geologic model of the Roosevelt Hot Springs hydrothermal system was developed by a review of the available literature. The hydrothermal system consists of a meteoric recharge area in the Mineral Mountains, fluid circulation paths to depth, a heat source, and an outflow plume. A conceptual model based on the available data can be simulated in the native state using parameters that fall within observed ranges. The model temperatures, recharge rates, and fluid travel times are sensitive to the permeability in the Mineral Mountains. The simulation results suggests the presence of a magma chamber at depth as the likely heat source. A two-dimensional study of the hydrothermal system can be used to establish boundary conditions for further study of the geothermal reservoir. 33 refs., 9 figs.

  16. Conceptual geologic model and native state model of the Roosevelt Hot Springs hydrothermal system

    SciTech Connect

    Faulder, D.D.

    1991-01-01

    A conceptual geologic model of the Roosevelt Hot Springs hydrothermal system was developed by a review of the available literature. The hydrothermal system consists of a meteoric recharge area in the Mineral Mountains, fluid circulation paths to depth, a heat source, and an outflow plume. A conceptual model based on the available data can be simulated in the native state using parameters that fall within observed ranges. The model temperatures, recharge rates, and fluid travel times are sensitive to the permeability in the Mineral Mountains. The simulation results suggests the presence of a magma chamber at depth as the likely heat source. A two-dimensional study of the hydrothermal system can be used to establish boundary conditions for further study of the geothermal reservoir.

  17. Validation of the Continuum of Care Conceptual Model for Athletic Therapy

    PubMed Central

    Lafave, Mark R.; Butterwick, Dale; Eubank, Breda

    2015-01-01

    Utilization of conceptual models in field-based emergency care currently borrows from existing standards of medical and paramedical professions. The purpose of this study was to develop and validate a comprehensive conceptual model that could account for injuries ranging from nonurgent to catastrophic events including events that do not follow traditional medical or prehospital care protocols. The conceptual model should represent the continuum of care from the time of initial injury spanning to an athlete's return to participation in their sport. Finally, the conceptual model should accommodate both novices and experts in the AT profession. This paper chronicles the content validation steps of the Continuum of Care Conceptual Model for Athletic Therapy (CCCM-AT). The stages of model development were domain and item generation, content expert validation using a three-stage modified Ebel procedure, and pilot testing. Only the final stage of the modified Ebel procedure reached a priori 80% consensus on three domains of interest: (1) heading descriptors; (2) the order of the model; (3) the conceptual model as a whole. Future research is required to test the use of the CCCM-AT in order to understand its efficacy in teaching and practice within the AT discipline. PMID:26464897

  18. Developing a TPCK-SRL Assessment Scheme for Conceptually Advancing Technology in Education

    ERIC Educational Resources Information Center

    Kohen, Zehavit; Kramarski, Bracha

    2012-01-01

    The present study aimed to: (a) develop a conceptual TPCK-SRL scheme for assessing teachers' integration of self-regulated learning (SRL) considerations while infusing technology into a TPCK classroom context (blending K = knowledge about T = technology, P = pedagogy, and C = content), which reflects all three knowledge components' dynamic…

  19. A Study of Child Variance, Volume 1: Conceptual Models; Conceptual Project in Emotional Disturbance.

    ERIC Educational Resources Information Center

    Rhodes, William C.; Tracy, Michael L.

    Presented are 11 papers discussing the following six models of emotional disturbance in children: biophysical, behavioral, psychodynamic, sociological, and ecological, models, and counter theory. Emotional disturbance is defined as a distinctive human state having multiple manifestations and involving disability, deviance, and alienation. All the…

  20. Comparison of conceptual designs for 25 kWe advanced Stirling conversion systems for dish electric applications

    NASA Technical Reports Server (NTRS)

    Shaltens, Richard K.; Schreiber, Jeffrey G.

    1989-01-01

    The Advanced Stirling Conversion System (ASCS) Project is managed by NASA Lewis Research Center through a cooperative interagency agreement with DOE. Conceptual designs for the ASCS's were completed under parallel contracts in 1987 by Mechanical Technology Inc. (MTI) of Latham, NY, and Stirling Technology Company (STC) of Richland, WA. Each design features a free-piston Stirling engine, a liquid metal heat pipe receiver, and a means to provide about 25 kW of electric power to a utility grid while meeting DOE's long term performance and cost goals. An independent assessment showed that both designs are manufacturable and have the potential to easily meet DOE's long term cost goals.

  1. Comparison of conceptual designs for 25 kWe advanced Stirling conversion systems for dish electric application

    NASA Technical Reports Server (NTRS)

    Shaltens, Richard K.; Schreiber, Jeffrey G.

    1989-01-01

    The Advanced Stirling Conversion System (ASCS) Project is managed by NASA Lewis Research Center through a cooperative interagency agreement with DOE. Conceptual designs for the ASCS's were completed under parallel contracts in 1987 by Mechanical Technology Inc. (MTI) of Latham, NY, and Stirling Technology Company (STC) of Richland, WA. Each design features a free-piston Stirling engine, a liquid metal heat pipe receiver, and a means to provide about 25 kW of electric power to a utility grid while meeting DOE's long term performance and cost goals. An independent assessment showed that both designs are manufacturable and have the potential to easily meet DOE's long term cost goals.

  2. CONCEPTUAL DESIGN AND ECONOMICS OF THE ADVANCED CO2 HYBRID POWER CYCLE

    SciTech Connect

    A. Nehrozoglu

    2004-12-01

    Research has been conducted under United States Department of Energy Contract DEFC26-02NT41621 to analyze the feasibility of a new type of coal-fired plant for electric power generation. This new type of plant, called the Advanced CO{sub 2} Hybrid Power Plant, offers the promise of efficiencies nearing 36 percent, while concentrating CO{sub 2} for 100% sequestration. Other pollutants, such as SO{sub 2} and NOx, are sequestered along with the CO{sub 2} yielding a zero emissions coal plant. The CO{sub 2} Hybrid is a gas turbine-steam turbine combined cycle plant that uses CO{sub 2} as its working fluid to facilitate carbon sequestration. The key components of the plant are a cryogenic air separation unit (ASU), a pressurized circulating fluidized bed gasifier, a CO{sub 2} powered gas turbine, a circulating fluidized bed boiler, and a super-critical pressure steam turbine. The gasifier generates a syngas that fuels the gas turbine and a char residue that, together with coal, fuels a CFB boiler to power the supercritical pressure steam turbine. Both the gasifier and the CFB boiler use a mix of ASU oxygen and recycled boiler flue gas as their oxidant. The resulting CFB boiler flue gas is essentially a mixture of oxygen, carbon dioxide and water. Cooling the CFB flue gas to 80 deg. F condenses most of the moisture and leaves a CO{sub 2} rich stream containing 3%v oxygen. Approximately 30% of this flue gas stream is further cooled, dried, and compressed for pipeline transport to the sequestration site (the small amount of oxygen in this stream is released and recycled to the system when the CO{sub 2} is condensed after final compression and cooling). The remaining 70% of the flue gas stream is mixed with oxygen from the ASU and is ducted to the gas turbine compressor inlet. As a result, the gas turbine compresses a mixture of carbon dioxide (ca. 64%v) and oxygen (ca. 32.5%v) rather than air. This carbon dioxide rich mixture then becomes the gas turbine working fluid and

  3. A Conceptual Model of Relationships among Constructivist Learning Environment Perceptions, Epistemological Beliefs, and Learning Approaches

    ERIC Educational Resources Information Center

    Ozkal, Kudret; Tekkaya, Ceren; Cakiroglu, Jale; Sungur, Semra

    2009-01-01

    This study proposed a conceptual model of relationships among constructivist learning environment perception variables (Personal Relevance, Uncertainty, Critical Voice, Shared Control, and Student Negotiation), scientific epistemological belief variables (fixed and tentative), and learning approach. It was proposed that learning environment…

  4. Student perception and conceptual development as represented by student mental models of atomic structure

    NASA Astrophysics Data System (ADS)

    Park, Eun Jung

    The nature of matter based upon atomic theory is a principal concept in science; hence, how to teach and how to learn about atoms is an important subject for science education. To this end, this study explored student perceptions of atomic structure and how students learn about this concept by analyzing student mental models of atomic structure. Changes in student mental models serve as a valuable resource for comprehending student conceptual development. Data was collected from students who were taking the introductory chemistry course. Responses to course examinations, pre- and post-questionnaires, and pre- and post-interviews were used to analyze student mental models of atomic structure. First, this study reveals that conceptual development can be achieved, either by elevating mental models toward higher levels of understanding or by developing a single mental model. This study reinforces the importance of higher-order thinking skills to enable students to relate concepts in order to construct a target model of atomic structure. Second, Bohr's orbital structure seems to have had a strong influence on student perceptions of atomic structure. With regard to this finding, this study suggests that it is instructionally important to teach the concept of "orbitals" related to "quantum theory." Third, there were relatively few students who had developed understanding at the level of the target model, which required student understanding of the basic ideas of quantum theory. This study suggests that the understanding of atomic structure based on the idea of quantum theory is both important and difficult. Fourth, this study included different student assessments comprised of course examinations, questionnaires, and interviews. Each assessment can be used to gather information to map out student mental models. Fifth, in the comparison of the pre- and post-interview responses, this study showed that high achieving students moved toward more improved models or to advanced

  5. Advances in Watershed Models and Modeling

    NASA Astrophysics Data System (ADS)

    Yeh, G. T.; Zhang, F.

    2015-12-01

    The development of watershed models and their applications to real-world problems has evolved significantly since 1960's. Watershed models can be classified based on what media are included, what processes are dealt with, and what approaches are taken. In term of media, a watershed may include segregated overland regime, river-canal-open channel networks, ponds-reservoirs-small lakes, and subsurface media. It may also include integrated media of all these or a partial set of these as well as man-made control structures. In term of processes, a watershed model may deal with coupled or decoupled hydrological and biogeochemical cycles. These processes include fluid flow, thermal transport, salinity transport, sediment transport, reactive transport, and biota and microbe kinetics. In terms of approaches, either parametric or physics-based approach can be taken. This talk discusses the evolution of watershed models in the past sixty years. The advances of watershed models center around their increasing design capability to foster these segregated or integrated media and coupled or decoupled processes. Widely used models developed by academia, research institutes, government agencies, and private industries will be reviewed in terms of the media and processes included as well as approaches taken. Many types of potential benchmark problems in general can be proposed and will be discussed. This presentation will focus on three benchmark problems of biogeochemical cycles. These three problems, dealing with water quality transport, will be formulated in terms of reactive transport. Simulation results will be illustrated using WASH123D, a watershed model developed and continuously updated by the author and his PhD graduates. Keywords: Hydrological Cycles, Biogeochemical Cycles, Biota Kinetics, Parametric Approach, Physics-based Approach, Reactive Transport.

  6. From the Conceptual Change Model to the Productive Ecological Koinos Model: Learning that transcends

    NASA Astrophysics Data System (ADS)

    Gelpi-Rodriguez, Phaedra

    This investigation presents the analysis of a model of teaching science called the Conceptual Change Model. This model stimulates students to identify their own and alternate science concepts, and to confront these concepts with dynamic situations that will incite a conceptual change and promote their ability to master and understand the conceptual systems that serve as foundations for scientific knowledge. During a previous research made by this investigator on the Conceptual Change Model, a proposal for a new teaching model came up which she called the Productive Ecological Koinos Model. This model incorporates, among other things, the teacher's reflection and inner thoughts about the concepts taught and the learning experiences achieved in concurrence with students. Using action research, an exploration and analysis was done that focused upon how students and teachers modified their perspective of science while testing the Productive Ecological Koinos Model during the teaching-learning processes that took place in a microbiology course. The action research design allows the researcher to analyze these points from the experiential perspective, while also allowing the researcher to participate in the study. The study employed qualitative research techniques such as reflective diaries, personal profiles of participants, document analysis, audio tape recordings and transcriptions. All of these techniques are accepted within action research (Elliot, 1991). The Wolcott Model was the data analysis method used in the research. The description, analysis and interpretation carried out allowed for the examination of the various components of the Productive Ecological Koinos Model with students and teachers as to the scientific terms virus and contagion, and their experiences during the learning process within and outside the classroom. From the analysis of the Model a modification cropped up which places emphasis on conscious introspection on the learning process. This new

  7. Understanding Co-development of Conceptual and Epistemic Understanding through Modeling Practices with Mobile Internet

    NASA Astrophysics Data System (ADS)

    Ryu, Suna; Han, Yuhwha; Paik, Seoung-Hey

    2015-04-01

    The present study explores how engaging in modeling practice, along with argumentation, leverages students' epistemic and conceptual understanding in an afterschool science/math class of 16 tenth graders. The study also explores how students used mobile Internet phones (smart phones) productively to support modeling practices. As the modeling practices became more challenging, student discussion occurred more often, from what to model to providing explanations for the phenomenon. Students came to argue about evidence that supported their model and how the model could explain target and related phenomena. This finding adds to the literature that modeling practice can help students improve conceptual understanding of subject knowledge as well as epistemic understanding.

  8. [A comprehensive and critical view of conceptual models for access to health services, 1970-2013].

    PubMed

    Arrivillaga, Marcela; Borrero, Yadira Eugenia

    2016-01-01

    The aim of this study was to critically analyze various conceptual models on access to health services described in the literature from 1970 to 2013. A systematic review was conducted on applied and theoretical research publications that explicitly conceptualized access to health services. The review included 25 articles that met the study's objectives. The analysis used a matrix containing the conceptual model's logic and its description. Access to health services was classified in five categories: (i) decent minimums, (ii) market-driven, (iii) factors and multicausality, (iv) needs-based, and (v) social justice and the right to health. The study concludes that the predominant concept of access in the literature has been the market logic of medical care services, linked to the logic of factors and multicausality. Meanwhile, no conceptual model was found for access to health services based explicitly on social justice and the right to health.

  9. Raft River Geothermal Area Data Models - Conceptual, Logical and Fact Models

    DOE Data Explorer

    Cuyler, David

    2012-07-19

    Conceptual and Logical Data Model for Geothermal Data Concerning Wells, Fields, Power Plants and Related Analyses at Raft River a. Logical Model for Geothermal Data Concerning Wells, Fields, Power Plants and Related Analyses, David Cuyler 2010 b. Fact Model for Geothermal Data Concerning Wells, Fields, Power Plants and Related Analyses, David Cuyler 2010 Derived from Tables, Figures and other Content in Reports from the Raft River Geothermal Project: "Technical Report on the Raft River Geothermal Resource, Cassia County, Idaho," GeothermEx, Inc., August 2002. "Results from the Short-Term Well Testing Program at the Raft River Geothermal Field, Cassia County, Idaho," GeothermEx, Inc., October 2004.

  10. Identification of Errors in the Hanford Site-Wide Groundwater Flow Model by Inverse Modeling of Alternative Conceptual Models

    NASA Astrophysics Data System (ADS)

    Cole, C. R.; Scheibe, T. D.; Vermeul, V. R.; Wurstner, S. K.; Thorne, P. D.; Freedman, V. L.; Murray, C. J.; Bergeron, M. P.

    2002-12-01

    A regional-scale, three-dimensional groundwater flow and transport modeling effort has been undertaken to quantify the environmental consequences of past waste disposal activities and support ongoing environmental management activities at the U.S. Department of Energy's Hanford Site. An important aspect of this effort is the identification and quantification of uncertainties associated with model predictions. It is recognized that such uncertainties arise not only from selection of inappropriate groundwater model parameters (parameter error), but also from the underlying conceptualization of the groundwater system (model error). Therefore, we have adopted an approach to uncertainty characterization that involves the evaluation of multiple alternative conceptual models (ACMs) within an inverse modeling framework. The initial step in implementation of the framework was the development of a multi-processor implementation of the UCODE inverse modeling system and application of the inverse framework to update parameter estimates from a prior deterministic model. A preliminary first-order uncertainty analysis was performed based on the model results. At the same time, site geologists developed an improved conceptual model of the 3D structure of the aquifer system. Inverse modeling of the updated conceptual model led to estimates of some parameters, especially specific yield, that were not plausible, indicating that there were problems with the conceptual model. As a result, additional ACMs were developed and subjected to inverse analysis, including an alternative with modified boundary conditions (leaky underlying bedrock), an alternative incorporating surface recharge modifications based on surface run-on from an adjacent topographic feature, and an alternative incorporating an improved description of the timing and volume of waste discharges arriving at the water table (upper model boundary). Model predictions of transient hydraulic heads under each ACM were compared

  11. A Confirmatory Structural Equation Model of Achievement Estimated by Dichotomous Attitudes, Interest, and Conceptual Understanding

    ERIC Educational Resources Information Center

    Kim, Minkee; Song, Jinwoong

    2010-01-01

    Many models in science education have tried to clarify the causal relationships of affective variables on student performance, by presenting theoretical models, exploratory SEM (structural equation models), and confirmatory SEM. Based on the literature, the recent AS-TI-CU model scrutinised the most robust stimuli of conceptual understanding (CU):…

  12. A Conceptual Model for Analysing Management Development in the UK Hospitality Industry

    ERIC Educational Resources Information Center

    Watson, Sandra

    2007-01-01

    This paper presents a conceptual, contingent model of management development. It explains the nature of the UK hospitality industry and its potential influence on MD practices, prior to exploring dimensions and relationships in the model. The embryonic model is presented as a model that can enhance our understanding of the complexities of the…

  13. On the optimal design of experiments for conceptual and predictive discrimination of hydrologic system models

    NASA Astrophysics Data System (ADS)

    Kikuchi, C. P.; Ferré, T. P. A.; Vrugt, J. A.

    2015-06-01

    Experimental design and data collection constitute two main steps of the iterative research cycle (aka the scientific method). To help evaluate competing hypotheses, it is critical to ensure that the experimental design is appropriate and maximizes information retrieval from the system of interest. Scientific hypothesis testing is implemented by comparing plausible model structures (conceptual discrimination) and sets of predictions (predictive discrimination). This research presents a new Discrimination-Inference (DI) methodology to identify prospective data sets highly suitable for either conceptual or predictive discrimination. The DI methodology uses preposterior estimation techniques to evaluate the expected change in the conceptual or predictive probabilities, as measured by the Kullback-Leibler divergence. We present two case studies with increasing complexity to illustrate implementation of the DI for maximizing information withdrawal from a system of interest. The case studies show that highly informative data sets for conceptual discrimination are in general those for which between-model (conceptual) uncertainty is large relative to the within-model (parameter) uncertainty, and the redundancy between individual measurements in the set is minimized. The optimal data set differs if predictive, rather than conceptual, discrimination is the experimental design objective. Our results show that DI analyses highlight measurements that can be used to address critical uncertainties related to the prediction of interest. Finally, we find that the optimal data set for predictive discrimination is sensitive to the predictive grouping definition in ways that are not immediately apparent from inspection of the model structure and parameter values.

  14. Conceptual design study for an advanced cab and visual system, volume 2

    NASA Technical Reports Server (NTRS)

    Rue, R. J.; Cyrus, M. L.; Garnett, T. A.; Nachbor, J. W.; Seery, J. A.; Starr, R. L.

    1980-01-01

    The performance, design, construction and testing requirements are defined for developing an advanced cab and visual system. The rotorcraft system integration simulator is composed of the advanced cab and visual system and the rotorcraft system motion generator, and is part of an existing simulation facility. User's applications for the simulator include rotorcraft design development, product improvement, threat assessment, and accident investigation.

  15. A Common Core for Active Conceptual Modeling for Learning from Surprises

    NASA Astrophysics Data System (ADS)

    Liddle, Stephen W.; Embley, David W.

    The new field of active conceptual modeling for learning from surprises (ACM-L) may be helpful in preserving life, protecting property, and improving quality of life. The conceptual modeling community has developed sound theory and practices for conceptual modeling that, if properly applied, could help analysts model and predict more accurately. In particular, we need to associate more semantics with links, and we need fully reified high-level objects and relationships that have a clear, formal underlying semantics that follows a natural, ontological approach. We also need to capture more dynamic aspects in our conceptual models to more accurately model complex, dynamic systems. These concepts already exist, and the theory is well developed; what remains is to link them with the ideas needed to predict system evolution, thus enabling risk assessment and response planning. No single researcher or research group will be able to achieve this ambitious vision alone. As a starting point, we recommend that the nascent ACM-L community agree on a common core model that supports all aspects—static and dynamic—needed for active conceptual modeling in support of learning from surprises. A common core will more likely gain the traction needed to sustain the extended ACM-L research effort that will yield the advertised benefits of learning from surprises.

  16. Three-dimensional conceptual model for the Hanford Site unconfined aquifer system: FY 1994 status report

    SciTech Connect

    Thorne, P.D.; Chamness, M.A.; Vermeul, V.R.; Macdonald, Q.C.; Schubert, S.E.

    1994-11-01

    This report documents work conducted during the fiscal year 1994 to development an improved three-dimensional conceptual model of ground-water flow in the unconfined aquifer system across the Hanford Site Ground-Water Surveillance Project, which is managed by Pacific Northwest Laboratory. The main objective of the ongoing effort to develop an improved conceptual model of ground-water flow is to provide the basis for improved numerical report models that will be capable of accurately predicting the movement of radioactive and chemical contaminant plumes in the aquifer beneath Hanford. More accurate ground-water flow models will also be useful in assessing the impacts of changes in facilities and operations. For example, decreasing volumes of operational waste-water discharge are resulting in a declining water table in parts of the unconfined aquifer. In addition to supporting numerical modeling, the conceptual model also provides a qualitative understanding of the movement of ground water and contaminants in the aquifer.

  17. Requirements for the conceptual design of advanced underground coal extraction systems

    NASA Astrophysics Data System (ADS)

    Gangal, M. D.; Lavin, M. L.

    1981-12-01

    Conceptual design requirements are presented for underground coal mining systems having substantially improved performance in the areas of production cost and miner safety. Mandatory performance levels are also set for miner health, environmental impact, and coal recovery. In addition to mandatory design goals and constraints, a number of desirable system characteristics are identified which must be assessed in terms of their impact on production cost and their compatibility with other system elements. Although developed for the flat lying, moderately thick seams of Central Appalachia, these requirements are designed to be easily adaptable to other coals.

  18. Requirements for the conceptual design of advanced underground coal extraction systems

    NASA Technical Reports Server (NTRS)

    Gangal, M. D.; Lavin, M. L.

    1981-01-01

    Conceptual design requirements are presented for underground coal mining systems having substantially improved performance in the areas of production cost and miner safety. Mandatory performance levels are also set for miner health, environmental impact, and coal recovery. In addition to mandatory design goals and constraints, a number of desirable system characteristics are identified which must be assessed in terms of their impact on production cost and their compatibility with other system elements. Although developed for the flat lying, moderately thick seams of Central Appalachia, these requirements are designed to be easily adaptable to other coals.

  19. Bayesian experimental design for identification of model propositions and conceptual model uncertainty reduction

    NASA Astrophysics Data System (ADS)

    Pham, Hai V.; Tsai, Frank T.-C.

    2015-09-01

    The lack of hydrogeological data and knowledge often results in different propositions (or alternatives) to represent uncertain model components and creates many candidate groundwater models using the same data. Uncertainty of groundwater head prediction may become unnecessarily high. This study introduces an experimental design to identify propositions in each uncertain model component and decrease the prediction uncertainty by reducing conceptual model uncertainty. A discrimination criterion is developed based on posterior model probability that directly uses data to evaluate model importance. Bayesian model averaging (BMA) is used to predict future observation data. The experimental design aims to find the optimal number and location of future observations and the number of sampling rounds such that the desired discrimination criterion is met. Hierarchical Bayesian model averaging (HBMA) is adopted to assess if highly probable propositions can be identified and the conceptual model uncertainty can be reduced by the experimental design. The experimental design is implemented to a groundwater study in the Baton Rouge area, Louisiana. We design a new groundwater head observation network based on existing USGS observation wells. The sources of uncertainty that create multiple groundwater models are geological architecture, boundary condition, and fault permeability architecture. All possible design solutions are enumerated using a multi-core supercomputer. Several design solutions are found to achieve an 80%-identifiable groundwater model in 5 years by using six or more existing USGS wells. The HBMA result shows that each highly probable proposition can be identified for each uncertain model component once the discrimination criterion is achieved. The variances of groundwater head predictions are significantly decreased by reducing posterior model probabilities of unimportant propositions.

  20. A Conceptual Modeling of spatio-temporal database to Estimate Runoff Changes in Urbanized Watersheds

    NASA Astrophysics Data System (ADS)

    Schäfer, A. L.

    2014-11-01

    This paper presents the development of a conceptual model of a database that allows the monitoring of changes in watersheds over time and verifies the impact of these changes on runoff. The conceptual model was developed using ER modeling techniques. ER diagrams were constructed from the semantic analysis of the variables involved in the issue of runoff in watersheds using the Curve Number method of Natural Resource Conservation Service. The conceptual model was developed based on the concepts of states and events, and the use of time as a basis for organizing spatial data allowed to record the time and place of any changes. The model of representation of spatial data based on object was employed. Through the proposed conceptual model, it is possible to store the results of several simulations for a watershed, linking each simulation to a specific event and identifying which scenario is valid at the time. Thus, it is possible to identify quantitative changes related to runoff over time and relate them to the events that caused them and the entities involved in such events. The conceptual model supports the existence of alternate realities, allowing the simulation and comparison of past and future scenarios.

  1. Advanced turbine systems program conceptual design and product development. Quarterly report, August--October 1995

    SciTech Connect

    1996-01-01

    This report describes the tasks completed for the advanced turbine systems program. The topics of the report include last row turbine blade development, single crystal blade casting development, ceramic materials development, combustion cylinder flow mapping, shroud film cooling, directional solidified valve development, shrouded blade cooling, closed-loop steam cooling, active tip clearance control, flow visualization tests, combustion noise investigation, TBC field testing, catalytic combustion development, optical diagnostics probe development, serpentine channel cooling tests, brush seal development, high efficiency compressor design, advanced air sealing development, advanced coating development, single crystal blade development, Ni-based disc forging development, and steam cooling effects on materials.

  2. A beginner's guide to writing the nursing conceptual model-based theoretical rationale.

    PubMed

    Gigliotti, Eileen; Manister, Nancy N

    2012-10-01

    Writing the theoretical rationale for a study can be a daunting prospect for novice researchers. Nursing's conceptual models provide excellent frameworks for placement of study variables, but moving from the very abstract concepts of the nursing model to the less abstract concepts of the study variables is difficult. Similar to the five-paragraph essay used by writing teachers to assist beginning writers to construct a logical thesis, the authors of this column present guidelines that beginners can follow to construct their theoretical rationale. This guide can be used with any nursing conceptual model but Neuman's model was chosen here as the exemplar.

  3. A conceptual model to empower software requirements conflict detection and resolution with rule-based reasoning

    NASA Astrophysics Data System (ADS)

    Ahmad, Sabrina; Jalil, Intan Ermahani A.; Ahmad, Sharifah Sakinah Syed

    2016-08-01

    It is seldom technical issues which impede the process of eliciting software requirements. The involvement of multiple stakeholders usually leads to conflicts and therefore the need of conflict detection and resolution effort is crucial. This paper presents a conceptual model to further improve current efforts. Hence, this paper forwards an improved conceptual model to assist the conflict detection and resolution effort which extends the model ability and improves overall performance. The significant of the new model is to empower the automation of conflicts detection and its severity level with rule-based reasoning.

  4. Combining Different Conceptual Change Methods within 5E Model: A Sample Teaching Design of "Cell" Concept and its Organelles

    ERIC Educational Resources Information Center

    Urey, Mustafa; Calik, Muammer

    2008-01-01

    Since students' misconceptions are not completely remedied by means of only one conceptual change method, the authors assume that using different conceptual methods embedded within the 5E model will not only be more effective in enhancing students' conceptual understanding, but also may eliminate all students' misconceptions. The aim of this study…

  5. Development of a system model for advanced small modular reactors.

    SciTech Connect

    Lewis, Tom Goslee,; Holschuh, Thomas Vernon,

    2014-01-01

    This report describes a system model that can be used to analyze three advance small modular reactor (SMR) designs through their lifetime. Neutronics of these reactor designs were evaluated using Monte Carlo N-Particle eXtended (MCNPX/6). The system models were developed in Matlab and Simulink. A major thrust of this research was the initial scoping analysis of Sandias concept of a long-life fast reactor (LLFR). The inherent characteristic of this conceptual design is to minimize the change in reactivity over the lifetime of the reactor. This allows the reactor to operate substantially longer at full power than traditional light water reactors (LWRs) or other SMR designs (e.g. high temperature gas reactor (HTGR)). The system model has subroutines for lifetime reactor feedback and operation calculations, thermal hydraulic effects, load demand changes and a simplified SCO2 Brayton cycle for power conversion.

  6. Moving from Victim to Survivor of Cultural Violence: A Conceptual Model

    ERIC Educational Resources Information Center

    Salazar, Carmen F.; Casto, Challon

    2008-01-01

    The authors propose the Moving From Victim to Survivor of Cultural Violence model, using the stages of D. W. Sue and D. Sue's (1999) Racial/Cultural Identity Development model. This conceptual model describes the process of first overcoming internalized sexism, domestic abuse, sexual harassment, rape, and other forms of oppression and then healing…

  7. Multi-Level Modeling of Dyadic Data in Sport Sciences: Conceptual, Statistical, and Practical Issues

    ERIC Educational Resources Information Center

    Gaudreau, Patrick; Fecteau, Marie-Claude; Perreault, Stephane

    2010-01-01

    The goal of this article is to present a series of conceptual, statistical, and practical issues in the modeling of multi-level dyadic data. Distinctions are made between distinguishable and undistinguishable dyads and several types of independent variables modeled at the dyadic level of analysis. Multi-level modeling equations are explained in a…

  8. Applying Model Analysis to a Resource-Based Analysis of the Force and Motion Conceptual Evaluation

    ERIC Educational Resources Information Center

    Smith, Trevor I.; Wittmann, Michael C.; Carter, Tom

    2014-01-01

    Previously, we analyzed the Force and Motion Conceptual Evaluation in terms of a resources-based model that allows for clustering of questions so as to provide useful information on how students correctly or incorrectly reason about physics. In this paper, we apply model analysis to show that the associated model plots provide more information…

  9. Conceptual design of an Advanced Stirling Conversion System for terrestrial power generation

    SciTech Connect

    Not Available

    1988-01-01

    This report describes the conceptual design of a system for converting solar energy into electricity using a free-piston Stirling engine directly coupled to a linear alternator. The system is designed for mounting at the focal plane of a 100 m/sup 2/ parabolic solar collector. It includes a receiver which is integrated with the engine heater head. Heat transfer from receiver to engine involves boiling liquid sodium at the heater surface of the receiver and condensing sodium vapor on the engine heater tubes. A sintered wick is located on the back surface of the receiver face to distribute the sodium and gravity is used to return the condensed sodium to a sump within the receiver. The system is connected to a utility power grid. The net power output from the system is 23.2 kWe at the design point (75 kWt into the receiver). Maximum power output is 26.7 kWe at the peak insolation level. Annual output is approximately 60,000 kWh for a site at Albuquerque, New Mexico. The manufacturing cost for the System has been estimated at approximately $8500 (1984 dollars). The installed cost goal is $13,000 (1984 dollars). Costs at the conceptual design level are only approximate but the estimates indicate that acceptable costs are attainable. 2 refs.

  10. Improvements in Thermal Protection Sizing Capabilities for TCAT: Conceptual Design for Advanced Space Transportation Systems

    NASA Technical Reports Server (NTRS)

    Olds, John R.; Izon, Stephen James

    2002-01-01

    The Thermal Calculation Analysis Tool (TCAT), originally developed for the Space Systems Design Lab at the Georgia Institute of Technology, is a conceptual design tool capable of integrating aeroheating analysis into conceptual reusable launch vehicle design. It provides Thermal Protection System (TPS) unit thicknesses and acreage percentages based on the geometry of the vehicle and a reference trajectory to be used in calculation of the total cost and weight of the vehicle design. TCAT has proven to be reasonably accurate at calculating the TPS unit weights for in-flight trajectories; however, it does not have the capability of sizing TPS materials above cryogenic fuel tanks for ground hold operations. During ground hold operations, the vehicle is held for a brief period (generally about two hours) during which heat transfer from the TPS materials to the cryogenic fuel occurs. If too much heat is extracted from the TPS material, the surface temperature may fall below the freezing point of water, thereby freezing any condensation that may be present at the surface of the TPS. Condensation or ice on the surface of the vehicle is potentially hazardous to the mission and can also damage the TPS. It is questionable whether or not the TPS thicknesses provided by the aeroheating analysis would be sufficiently thick to insulate the surface of the TPS from the heat transfer to the fuel. Therefore, a design tool has been developed that is capable of sizing TPS materials at these cryogenic fuel tank locations to augment TCAT's TPS sizing capabilities.

  11. Conceptual model of sediment processes in the upper Yuba River watershed, Sierra Nevada, CA

    USGS Publications Warehouse

    Curtis, J.A.; Flint, L.E.; Alpers, C.N.; Yarnell, S.M.

    2005-01-01

    This study examines the development of a conceptual model of sediment processes in the upper Yuba River watershed; and we hypothesize how components of the conceptual model may be spatially distributed using a geographical information system (GIS). The conceptual model illustrates key processes controlling sediment dynamics in the upper Yuba River watershed and was tested and revised using field measurements, aerial photography, and low elevation videography. Field reconnaissance included mass wasting and channel storage inventories, assessment of annual channel change in upland tributaries, and evaluation of the relative importance of sediment sources and transport processes. Hillslope erosion rates throughout the study area are relatively low when compared to more rapidly eroding landscapes such as the Pacific Northwest and notable hillslope sediment sources include highly erodible andesitic mudflows, serpentinized ultramafics, and unvegetated hydraulic mine pits. Mass wasting dominates surface erosion on the hillslopes; however, erosion of stored channel sediment is the primary contributor to annual sediment yield. We used GIS to spatially distribute the components of the conceptual model and created hillslope erosion potential and channel storage models. The GIS models exemplify the conceptual model in that landscapes with low potential evapotranspiration, sparse vegetation, steep slopes, erodible geology and soils, and high road densities display the greatest hillslope erosion potential and channel storage increases with increasing stream order. In-channel storage in upland tributaries impacted by hydraulic mining is an exception. Reworking of stored hydraulic mining sediment in low-order tributaries continues to elevate upper Yuba River sediment yields. Finally, we propose that spatially distributing the components of a conceptual model in a GIS framework provides a guide for developing more detailed sediment budgets or numerical models making it an

  12. Using conceptual models as a planning and evaluation tool in conservation.

    PubMed

    Margoluis, Richard; Stem, Caroline; Salafsky, Nick; Brown, Marcia

    2009-05-01

    Conservation projects are dynamic interventions that occur in complex contexts involving intricate interactions of social, political, economic, cultural, and environmental factors. These factors are constantly changing over time and space as managers learn more about the context within which they work. This complex context poses challenges for planning and evaluating conservation project. In order for conservation managers and evaluation professionals to design good interventions and measure project success, they simultaneously need to embrace and deconstruct contextual complexity. In this article, we describe conceptual models--a tool that helps articulate and make explicit assumptions about a project's context and what a project team hopes to achieve. We provide real-world examples of conceptual models, discuss the relationship between conceptual models and other evaluation tools, and describe various ways that conceptual models serve as a key planning and evaluation tool. These include, for example, that they document assumptions about a project site and they provide a basis for analyzing theories of change. It is impractical to believe that we can completely eliminate detail or dynamic complexity in projects. Nevertheless, conceptual models can help reduce the effects of this complexity by helping us understand it.

  13. Navigating Tensions Between Conceptual and Metaconceptual Goals in the Use of Models

    NASA Astrophysics Data System (ADS)

    Delgado, Cesar

    2015-04-01

    Science education involves learning about phenomena at three levels: concrete (facts and generalizations), conceptual (concepts and theories), and metaconceptual (epistemology) (Snir et al. in J Sci Educ Technol 2(2):373-388, 1993). Models are key components in science, can help build conceptual understanding, and may also build metaconceptual understanding. Technology can transform teaching and learning by turning models into interactive simulations that learners can investigate. This paper identifies four characteristics of models and simulations that support conceptual learning but misconstrue models and science at a metaconceptual level. Ahistorical models combine the characteristics of several historical models; they conveniently compile ideas but misrepresent the history of science (Gilbert in Int J Sci Math Educ 2(2):115-130, 2004). Teleological models explain behavior in terms of a final cause; they can lead to useful heuristics but imply purpose in processes driven by chance and probability (Talanquer in Int J Sci Educ 29(7):853-870, 2007). Epistemological overreach occurs when models or simulations imply greater certainty and knowledge about phenomena than warranted; conceptualizing nature as being well known (e.g., having a mathematical structure) poses the danger of conflating model and reality or data and theory. Finally, models are inevitably ontologically impoverished. Real-world deviations and many variables are left out of models, as models' role is to simplify. Models and simulations also lose much of the sensory data present in phenomena. Teachers, designers, and professional development designers and facilitators must thus navigate the tension between conceptual and metaconceptual learning when using models and simulations. For each characteristic, examples are provided, along with recommendations for instruction and design. Prompts for explicit reflective activities around models are provided for each characteristic

  14. Waste Receiving and Processing Facility Module 2A: Advanced Conceptual Design Report. Volume 1

    SciTech Connect

    Not Available

    1994-03-01

    This ACDR was performed following completed of the Conceptual Design Report in July 1992; the work encompassed August 1992 to January 1994. Mission of the WRAP Module 2A facility is to receive, process, package, certify, and ship for permanent burial at the Hanford site disposal facilities the Category 1 and 3 contact handled low-level radioactive mixed wastes that are currently in retrievable storage at Hanford and are forecast to be generated over the next 30 years by Hanford, and waste to be shipped to Hanford from about DOE sites. This volume provides an introduction to the ACDR process and the scope of the task along with a project summary of the facility, treatment technologies, cost, and schedule. Major areas of departure from the CDR are highlighted. Descriptions of the facility layout and operations are included.

  15. Development of a Conceptual Chum Salmon Emergence Model for Ives Island

    SciTech Connect

    Murray, Christopher J.; Geist, David R.; Arntzen, Evan V.; Bott, Yi-Ju; Nabelek, Marc A.

    2011-02-09

    The objective of the study described herein was to develop a conceptual model of chum salmon emergence that was based on empirical water temperature of the riverbed and river in specific locations where chum salmon spawn in the Ives Island area. The conceptual model was developed using water temperature data that have been collected in the past and are currently being collected in the Ives Island area. The model will be useful to system operators who need to estimate the complete distribution of chum salmon emergence (first emergence through final emergence) in order to balance chum salmon redd protection and power system operation.

  16. Facility for Advanced Accelerator Experimental Tests at SLAC (FACET) Conceptual Design Report

    SciTech Connect

    Amann, J.; Bane, K.; /SLAC

    2009-10-30

    This Conceptual Design Report (CDR) describes the design of FACET. It will be updated to stay current with the developing design of the facility. This CDR begins as the baseline conceptual design and will evolve into an 'as-built' manual for the completed facility. The Executive Summary, Chapter 1, gives an introduction to the FACET project and describes the salient features of its design. Chapter 2 gives an overview of FACET. It describes the general parameters of the machine and the basic approaches to implementation. The FACET project does not include the implementation of specific scientific experiments either for plasma wake-field acceleration for other applications. Nonetheless, enough work has been done to define potential experiments to assure that the facility can meet the requirements of the experimental community. Chapter 3, Scientific Case, describes the planned plasma wakefield and other experiments. Chapter 4, Technical Description of FACET, describes the parameters and design of all technical systems of FACET. FACET uses the first two thirds of the existing SLAC linac to accelerate the beam to about 20GeV, and compress it with the aid of two chicanes, located in Sector 10 and Sector 20. The Sector 20 area will include a focusing system, the generic experimental area and the beam dump. Chapter 5, Management of Scientific Program, describes the management of the scientific program at FACET. Chapter 6, Environment, Safety and Health and Quality Assurance, describes the existing programs at SLAC and their application to the FACET project. It includes a preliminary analysis of safety hazards and the planned mitigation. Chapter 7, Work Breakdown Structure, describes the structure used for developing the cost estimates, which will also be used to manage the project. The chapter defines the scope of work of each element down to level 3.

  17. Conceptual design of a self-deployable, high performance parabolic concentrator for advanced solar-dynamic power systems

    NASA Technical Reports Server (NTRS)

    Dehne, Hans J.

    1991-01-01

    NASA has initiated technology development programs to develop advanced solar dynamic power systems and components for space applications beyond 2000. Conceptual design work that was performed is described. The main efforts were the: (1) conceptual design of self-deploying, high-performance parabolic concentrator; and (2) materials selection for a lightweight, shape-stable concentrator. The deployment concept utilizes rigid gore-shaped reflective panels. The assembled concentrator takes an annular shape with a void in the center. This deployable concentrator concept is applicable to a range of solar dynamic power systems of 25 kW sub e to in excess of 75 kW sub e. The concept allows for a family of power system sizes all using the same packaging and deployment technique. The primary structural material selected for the concentrator is a polyethyl ethylketone/carbon fiber composite also referred to as APC-2 or Vitrex. This composite has a nearly neutral coefficient of thermal expansion which leads to shape stable characteristics under thermal gradient conditions. Substantial efforts were undertaken to produce a highly specular surface on the composite. The overall coefficient of thermal expansion of the composite laminate is near zero, but thermally induced stresses due to micro-movement of the fibers and matrix in relation to each other cause the surface to become nonspecular.

  18. Spacecraft Conceptual Design for the 8-Meter Advanced Technology Large Aperture Space Telescope (ATLAST)

    NASA Technical Reports Server (NTRS)

    Hopkins, Randall C.; Capizzo, Peter; Fincher, Sharon; Hornsby, Linda S.; Jones, David

    2010-01-01

    The Advanced Concepts Office at Marshall Space Flight Center completed a brief spacecraft design study for the 8-meter monolithic Advanced Technology Large Aperture Space Telescope (ATLAST-8m). This spacecraft concept provides all power, communication, telemetry, avionics, guidance and control, and thermal control for the observatory, and inserts the observatory into a halo orbit about the second Sun-Earth Lagrange point. The multidisciplinary design team created a simple spacecraft design that enables component and science instrument servicing, employs articulating solar panels for help with momentum management, and provides precise pointing control while at the same time fast slewing for the observatory.

  19. Adaptive Modeling, Engineering Analysis and Design of Advanced Aerospace Vehicles

    NASA Technical Reports Server (NTRS)

    Mukhopadhyay, Vivek; Hsu, Su-Yuen; Mason, Brian H.; Hicks, Mike D.; Jones, William T.; Sleight, David W.; Chun, Julio; Spangler, Jan L.; Kamhawi, Hilmi; Dahl, Jorgen L.

    2006-01-01

    This paper describes initial progress towards the development and enhancement of a set of software tools for rapid adaptive modeling, and conceptual design of advanced aerospace vehicle concepts. With demanding structural and aerodynamic performance requirements, these high fidelity geometry based modeling tools are essential for rapid and accurate engineering analysis at the early concept development stage. This adaptive modeling tool was used for generating vehicle parametric geometry, outer mold line and detailed internal structural layout of wing, fuselage, skin, spars, ribs, control surfaces, frames, bulkheads, floors, etc., that facilitated rapid finite element analysis, sizing study and weight optimization. The high quality outer mold line enabled rapid aerodynamic analysis in order to provide reliable design data at critical flight conditions. Example application for structural design of a conventional aircraft and a high altitude long endurance vehicle configuration are presented. This work was performed under the Conceptual Design Shop sub-project within the Efficient Aerodynamic Shape and Integration project, under the former Vehicle Systems Program. The project objective was to design and assess unconventional atmospheric vehicle concepts efficiently and confidently. The implementation may also dramatically facilitate physics-based systems analysis for the NASA Fundamental Aeronautics Mission. In addition to providing technology for design and development of unconventional aircraft, the techniques for generation of accurate geometry and internal sub-structure and the automated interface with the high fidelity analysis codes could also be applied towards the design of vehicles for the NASA Exploration and Space Science Mission projects.

  20. Conceptual design of MgB2 coil for the 100 MJ SMES of advanced superconducting power conditioning system (ASPCS)

    NASA Astrophysics Data System (ADS)

    Atomura, Naoki; Takahashi, Toshinori; Amata, Hiroto; Iwasaki, Tatsuya; Son, Kyoungwoo; Miyagi, Daisuke; Tsuda, Makoto; Hamajima, Takataro; Shintomi, Takakazu; Makida, Yasuhiro; Takao, Tomoaki; Munakata, Kohe; Kajiwara, Masataka

    In order to reduce global carbon-dioxide in the world, we propose an Advanced Superconducting Power Conditioning System (ASPCS) which is composed of 5 MW renewable energy resources and 1 MW hybrid storage system. The hybrid storage system is composed of FC-H2-EL and SMES which is installed adjacent to a LH2 station for vehicles. Since the SMES can be operated at 20 K which is a saturated temperature of LH2, we can use MgB2 superconductors. In the ASPCS, 100 MJ storage capacities of the SMES should be required. This paper focuses on studies into a conceptual design of SMES toroidal coil composed of the MgB2 and indirectly cooled by LH2.

  1. Conceptual Model of Offshore Wind Environmental Risk Evaluation System

    SciTech Connect

    Anderson, Richard M.; Copping, Andrea E.; Van Cleve, Frances B.; Unwin, Stephen D.; Hamilton, Erin L.

    2010-06-01

    In this report we describe the development of the Environmental Risk Evaluation System (ERES), a risk-informed analytical process for estimating the environmental risks associated with the construction and operation of offshore wind energy generation projects. The development of ERES for offshore wind is closely allied to a concurrent process undertaken to examine environmental effects of marine and hydrokinetic (MHK) energy generation, although specific risk-relevant attributes will differ between the MHK and offshore wind domains. During FY10, a conceptual design of ERES for offshore wind will be developed. The offshore wind ERES mockup described in this report will provide a preview of the functionality of a fully developed risk evaluation system that will use risk assessment techniques to determine priority stressors on aquatic organisms and environments from specific technology aspects, identify key uncertainties underlying high-risk issues, compile a wide-range of data types in an innovative and flexible data organizing scheme, and inform planning and decision processes with a transparent and technically robust decision-support tool. A fully functional version of ERES for offshore wind will be developed in a subsequent phase of the project.

  2. Chemical Kinetic Modeling of Advanced Transportation Fuels

    SciTech Connect

    PItz, W J; Westbrook, C K; Herbinet, O

    2009-01-20

    Development of detailed chemical kinetic models for advanced petroleum-based and nonpetroleum based fuels is a difficult challenge because of the hundreds to thousands of different components in these fuels and because some of these fuels contain components that have not been considered in the past. It is important to develop detailed chemical kinetic models for these fuels since the models can be put into engine simulation codes used for optimizing engine design for maximum efficiency and minimal pollutant emissions. For example, these chemistry-enabled engine codes can be used to optimize combustion chamber shape and fuel injection timing. They also allow insight into how the composition of advanced petroleum-based and non-petroleum based fuels affect engine performance characteristics. Additionally, chemical kinetic models can be used separately to interpret important in-cylinder experimental data and gain insight into advanced engine combustion processes such as HCCI and lean burn engines. The objectives are: (1) Develop detailed chemical kinetic reaction models for components of advanced petroleum-based and non-petroleum based fuels. These fuels models include components from vegetable-oil-derived biodiesel, oil-sand derived fuel, alcohol fuels and other advanced bio-based and alternative fuels. (2) Develop detailed chemical kinetic reaction models for mixtures of non-petroleum and petroleum-based components to represent real fuels and lead to efficient reduced combustion models needed for engine modeling codes. (3) Characterize the role of fuel composition on efficiency and pollutant emissions from practical automotive engines.

  3. Advancements in engineering turbulence modeling

    NASA Technical Reports Server (NTRS)

    Shih, T.-H.

    1991-01-01

    Some new developments in two-equation models and second order closure models are presented. Two-equation models (k-epsilon models) have been widely used in computational fluid dynamics (CFD) for engineering problems. Most of low-Reynolds number two-equation models contain some wall-distance damping functions to account for the effect of wall on turbulence. However, this often causes the confusion and difficulties in computing flows with complex geometry and also needs an ad hoc treatment near the separation and reattachment points. A set of modified two-equation models is proposed to remove the aforementioned shortcomings. The calculations using various two-equation models are compared with direct numerical simulations of channel flow and flat boundary layers. Development of a second order closure model is also discussed with emphasis on the modeling of pressure related correlation terms and dissipation rates in the second moment equations. All the existing models poorly predict the normal stresses near the wall and fail to predict the 3-D effect of mean flow on the turbulence (e.g. decrease in the shear stress caused by the cross flow in the boundary layer). The newly developed second order near-wall turbulence model is described and is capable of capturing the near-wall behavior of turbulence as well as the effect of 3-D mean flow on the turbulence.

  4. Model-based advanced process control of coagulation.

    PubMed

    Baxter, C W; Shariff, R; Stanley, S J; Smith, D W; Zhang, Q; Saumer, E D

    2002-01-01

    The drinking water treatment industry has seen a recent increase in the use of artificial neural networks (ANNs) for process modelling and offline process control tools and applications. While conceptual frameworks for integrating the ANN technology into the real-time control of complex treatment processes have been proposed, actual working systems have yet to be developed. This paper presents development and application of an ANN model-based advanced process control system for the coagulation process at a pilot-scale water treatment facility in Edmonton, Alberta, Canada. The system was successfully used to maintain a user-defined set point for effluent quality, by automatically varying operating conditions in response to changes in influent water quality. This new technology has the potential to realize significant operational cost saving for utilities when applied in full-scale applications.

  5. Advances in Treatment Integrity Research: Multidisciplinary Perspectives on the Conceptualization, Measurement, and Enhancement of Treatment Integrity

    ERIC Educational Resources Information Center

    Schulte, Ann C.; Easton, Julia E.; Parker, Justin

    2009-01-01

    Documenting treatment integrity is an important issue in research and practice in any discipline concerned with prevention and intervention. However, consensus concerning the dimensions of treatment integrity and how they should be measured has yet to emerge. Advances from three areas in which significant treatment integrity work has taken…

  6. Conceptual design of an integrated technology model for carbon policy assessment.

    SciTech Connect

    Backus, George A.; Dimotakes, Paul E.

    2011-01-01

    This report describes the conceptual design of a technology choice model for understanding strategies to reduce carbon intensity in the electricity sector. The report considers the major modeling issues affecting technology policy assessment and defines an implementable model construct. Further, the report delineates the basis causal structure of such a model and attempts to establish the technical/algorithmic viability of pursuing model development along with the associated analyses.

  7. Evaluating quantitative and conceptual models of speech production: how does SLAM fare?

    PubMed

    Walker, Grant M; Hickok, Gregory

    2016-04-01

    In a previous publication, we presented a new computational model called SLAM (Walker & Hickok, Psychonomic Bulletin & Review doi: 10.3758/s13423-015-0903 ), based on the hierarchical state feedback control (HSFC) theory (Hickok Nature Reviews Neuroscience, 13(2), 135-145, 2012). In his commentary, Goldrick (Psychonomic Bulletin & Review doi: 10.3758/s13423-015-0946-9 ) claims that SLAM does not represent a theoretical advancement, because it cannot be distinguished from an alternative lexical + postlexical (LPL) theory proposed by Goldrick and Rapp (Cognition, 102(2), 219-260, 2007). First, we point out that SLAM implements a portion of a conceptual model (HSFC) that encompasses LPL. Second, we show that SLAM accounts for a lexical bias present in sound-related errors that LPL does not explain. Third, we show that SLAM's explanatory advantage is not a result of approximating the architectural or computational assumptions of LPL, since an implemented version of LPL fails to provide the same fit improvements as SLAM. Finally, we show that incorporating a mechanism that violates some core theoretical assumptions of LPL-making it more like SLAM in terms of interactivity-allows the model to capture some of the same effects as SLAM. SLAM therefore provides new modeling constraints regarding interactions among processing levels, while also elaborating on the structure of the phonological level. We view this as evidence that an integration of psycholinguistic, neuroscience, and motor control approaches to speech production is feasible and may lead to substantial new insights. PMID:26537953

  8. Conceptual Model of Iodine Behavior in the Subsurface at the Hanford Site

    SciTech Connect

    Truex, Michael J.; Lee, Brady D.; Johnson, Christian D.; Qafoku, Nikolla P.; Last, George V.; Lee, Michelle H.; Kaplan, Daniel I.

    2015-09-01

    The fate and transport of 129I in the environment and potential remediation technologies are currently being studied as part of environmental remediation activities at the Hanford Site. A conceptual model describing the nature and extent of subsurface contamination, factors that control plume behavior, and factors relevant to potential remediation processes is needed to support environmental remedy decisions. Because 129I is an uncommon contaminant, relevant remediation experience and scientific literature are limited. Thus, the conceptual model also needs to both describe known contaminant and biogeochemical process information and to identify aspects about which additional information needed to effectively support remedy decisions. this document summarizes the conceptual model of iodine behavior relevant to iodine in the subsurface environment at the Hanford site.

  9. A Dyadic Approach: Applying a Developmental-Conceptual Model to Couples Coping with Chronic Illness

    ERIC Educational Resources Information Center

    Checton, Maria G.; Magsamen-Conrad, Kate; Venetis, Maria K.; Greene, Kathryn

    2015-01-01

    The purpose of the present study was to apply Berg and Upchurch's developmental-conceptual model toward a better understanding of how couples cope with chronic illness. Specifically, a model was hypothesized in which proximal factors (relational quality), dyadic appraisal (illness interference), and dyadic coping (partner support) influence…

  10. Learning Goal Orientation, Formal Mentoring, and Leadership Competence in HRD: A Conceptual Model

    ERIC Educational Resources Information Center

    Kim, Sooyoung

    2007-01-01

    Purpose: The purpose of this paper is to suggest a conceptual model of formal mentoring as a leadership development initiative including "learning goal orientation", "mentoring functions", and "leadership competencies" as key constructs of the model. Design/methodology/approach: Some empirical studies, though there are not many, will provide…

  11. Conceptual Incoherence as a Result of the Use of Multiple Historical Models in School Textbooks

    ERIC Educational Resources Information Center

    Gericke, Niklas M.; Hagberg, Mariana

    2010-01-01

    This paper explores the occurrence of conceptual incoherence in upper secondary school textbooks resulting from the use of multiple historical models. Swedish biology and chemistry textbooks, as well as a selection of books from English speaking countries, were examined. The purpose of the study was to identify which models are used to represent…

  12. Career and Technical Education (CTE) Student Success in Community Colleges: A Conceptual Model

    ERIC Educational Resources Information Center

    Hirschy, Amy S.; Bremer, Christine D.; Castellano, Marisa

    2011-01-01

    Career and technical education (CTE) students pursuing occupational associate's degrees or certificates differ from students seeking academic majors at 2-year institutions in several ways. This article examines several theoretical models of student persistence and offers a conceptual model of student success focused on CTE students in community…

  13. Introductory Biology Students' Conceptual Models and Explanations of the Origin of Variation

    ERIC Educational Resources Information Center

    Bray Speth, Elena; Shaw, Neil; Momsen, Jennifer; Reinagel, Adam; Le, Paul; Taqieddin, Ranya; Long, Tammy

    2014-01-01

    Mutation is the key molecular mechanism generating phenotypic variation, which is the basis for evolution. In an introductory biology course, we used a model-based pedagogy that enabled students to integrate their understanding of genetics and evolution within multiple case studies. We used student-generated conceptual models to assess…

  14. Understanding Co-Development of Conceptual and Epistemic Understanding through Modeling Practices with Mobile Internet

    ERIC Educational Resources Information Center

    Ryu, Suna; Han, Yuhwha; Paik, Seoung-Hey

    2015-01-01

    The present study explores how engaging in modeling practice, along with argumentation, leverages students' epistemic and conceptual understanding in an afterschool science/math class of 16 tenth graders. The study also explores how students used mobile Internet phones (smart phones) productively to support modeling practices. As the modeling…

  15. A Conceptual Model of Intrapreneurship in the Iranian Agricultural Extension Organization: Implications for HRD

    ERIC Educational Resources Information Center

    Karimi, Asef; Malekmohamadi, Iraj; Daryani, Mahmoud Ahmadpour; Rezvanfar, Ahmad

    2011-01-01

    Purpose: This study seeks to build a conceptual model of agricultural extension intrapreneurship that discusses the concept and phenomenon of intrapreneurship as well as its prerequisites and outcomes. The proposed model is intended to depict the main factors that affect the phenomena of intrapreneurship within the agricultural extension…

  16. The Role of Model Building in Problem Solving and Conceptual Change

    ERIC Educational Resources Information Center

    Lee, Chwee Beng; Jonassen, David; Teo, Timothy

    2011-01-01

    This study examines the effects of the activity of building systems models for school-based problems on problem solving and on conceptual change in elementary science classes. During a unit on the water cycle in an Asian elementary school, students constructed systems models of the water cycle. We found that representing ill-structured problems as…

  17. Conceptual Models: Broadening Diagnostic Perspectives on Communication Disorders in Emotionally and Behaviorally Disordered Children.

    ERIC Educational Resources Information Center

    Doherty, Mairin; Hummel, Lauren J.

    1990-01-01

    The article offers an exploratory analysis of three conceptual models used in psychiatry. Through a case presentation, the article demonstrates each model's basic premises and implications. Patterns of speech, language, and communication impairment should be investigated from all three perspectives: biodynamic, psychodynamic, and sociodynamic.…

  18. A Conceptual Model of Management Learning in Micro Businesses: Implications for Research and Policy

    ERIC Educational Resources Information Center

    Devins, David; Gold, Jeff; Johnson, Steve; Holden, Rick

    2005-01-01

    Purpose: This article proposes the development of a conceptual model to help understand the nature of management learning in the micro business context and to inform research and policy discourse. Design/Methodology/Approach: The model is developed on the basis of a literature search and review of academic and grey literature. Findings: The…

  19. Use of Conceptual Models in Case Studies: Dynamic Concept Analysis. Research Bulletin 78.

    ERIC Educational Resources Information Center

    Kontiainen, Seppo; And Others

    Dynamic Concept Analysis (DCA) is introduced as a means of building conceptual models in case studies and using information of concept relations in developing general and individual models to depict a particular phenomenon. DCA enables holistic studies of complex phenomena and analyzes the relationships between concepts to express these relations…

  20. Developing and Validating a Conceptual Model of Recurring Problems in Teaching Clinic

    ERIC Educational Resources Information Center

    Smith, C. Scott; Morris, Magdalena; Hill, William; Francovich, Chris; Christiano, Jennifer

    2006-01-01

    Recurrent problems in medical teaching clinic are common and difficult to address because of complex interpersonal dynamics. To minimize this difficulty, we developed a conceptual model that simplifies problems and identifies the root cause of tension between groups in clinic. We used recursive analysis and modeling of the data from a larger…

  1. Conceptualization of an R&D Based Learning-to-Innovate Model for Science Education

    ERIC Educational Resources Information Center

    Lai, Oiki Sylvia

    2013-01-01

    The purpose of this research was to conceptualize an R & D based learning-to-innovate (LTI) model. The problem to be addressed was the lack of a theoretical L TI model, which would inform science pedagogy. The absorptive capacity (ACAP) lens was adopted to untangle the R & D LTI phenomenon into four learning processes: problem-solving via…

  2. Construction of a conceptual model of transport system for a coal mining region

    NASA Astrophysics Data System (ADS)

    Pristupa, Yu D.; Fryanov, V. N.; Pavlova, L. D.

    2016-10-01

    The methodological approaches to creation of a conceptual model of complex transport system for coal-mining region are substantiated. In the structure of the system base model the ensemble of local interconnected subsystems is distinguished. The local structure of the traffic management system of cargo transportation company is developed, the factors and indicators affecting the efficiency of cargo management are highlighted.

  3. A Conceptual Model of Medical Student Well-Being: Promoting Resilience and Preventing Burnout

    ERIC Educational Resources Information Center

    Dunn, Laura B.; Iglewicz, Alana; Moutier, Christine

    2008-01-01

    Objective: This article proposes and illustrates a conceptual model of medical student well-being. Method: The authors reviewed the literature on medical student stress, coping, and well-being and developed a model of medical student coping termed the "coping reservoir." Results: The reservoir can be replenished or drained by various aspects of…

  4. Using Analogy and Model to Enhance Conceptual Change in Thai Middle School Students

    ERIC Educational Resources Information Center

    Wichaidit, Sittichai; Wongyounoi, Somson; Dechsri, Precharn; Chaivisuthangkura, Parin

    2011-01-01

    This study examined conceptual change of Thai middle school students after learning photosynthesis with analogy and model. The analogy mapped key features from the analog (cooking food) to the target concept (photosynthesis). Modeling photosynthesis activity provided the opportunity for students to understand how plants use sugar to synthesize…

  5. Civic Responsibility and the Student Athlete: Validating a New Conceptual Model

    ERIC Educational Resources Information Center

    Gayles, Joy Gaston; Rockenbach, Alyssa Bryant; Davis, Heather A.

    2012-01-01

    This study tested a new conceptual model that explains how precollege traits, college culture, and cocurricular engagement impact civic responsibility by athletic status. The results showed group differences on engagement in charitable activities. Moreover, the model has utility for predicting social activism and charitable involvement regardless…

  6. Multi-model groundwater-management optimization: reconciling disparate conceptual models

    NASA Astrophysics Data System (ADS)

    Timani, Bassel; Peralta, Richard

    2015-09-01

    Disagreement among policymakers often involves policy issues and differences between the decision makers' implicit utility functions. Significant disagreement can also exist concerning conceptual models of the physical system. Disagreement on the validity of a single simulation model delays discussion on policy issues and prevents the adoption of consensus management strategies. For such a contentious situation, the proposed multi-conceptual model optimization (MCMO) can help stakeholders reach a compromise strategy. MCMO computes mathematically optimal strategies that simultaneously satisfy analogous constraints and bounds in multiple numerical models that differ in boundary conditions, hydrogeologic stratigraphy, and discretization. Shadow prices and trade-offs guide the process of refining the first MCMO-developed `multi-model strategy into a realistic compromise management strategy. By employing automated cycling, MCMO is practical for linear and nonlinear aquifer systems. In this reconnaissance study, MCMO application to the multilayer Cache Valley (Utah and Idaho, USA) river-aquifer system employs two simulation models with analogous background conditions but different vertical discretization and boundary conditions. The objective is to maximize additional safe pumping (beyond current pumping), subject to constraints on groundwater head and seepage from the aquifer to surface waters. MCMO application reveals that in order to protect the local ecosystem, increased groundwater pumping can satisfy only 40 % of projected water demand increase. To explore the possibility of increasing that pumping while protecting the ecosystem, MCMO clearly identifies localities requiring additional field data. MCMO is applicable to other areas and optimization problems than used here. Steps to prepare comparable sub-models for MCMO use are area-dependent.

  7. Towards a Bayesian total error analysis of conceptual rainfall-runoff models: Characterising model error using storm-dependent parameters

    NASA Astrophysics Data System (ADS)

    Kuczera, George; Kavetski, Dmitri; Franks, Stewart; Thyer, Mark

    2006-11-01

    SummaryCalibration and prediction in conceptual rainfall-runoff (CRR) modelling is affected by the uncertainty in the observed forcing/response data and the structural error in the model. This study works towards the goal of developing a robust framework for dealing with these sources of error and focuses on model error. The characterisation of model error in CRR modelling has been thwarted by the convenient but indefensible treatment of CRR models as deterministic descriptions of catchment dynamics. This paper argues that the fluxes in CRR models should be treated as stochastic quantities because their estimation involves spatial and temporal averaging. Acceptance that CRR models are intrinsically stochastic paves the way for a more rational characterisation of model error. The hypothesis advanced in this paper is that CRR model error can be characterised by storm-dependent random variation of one or more CRR model parameters. A simple sensitivity analysis is used to identify the parameters most likely to behave stochastically, with variation in these parameters yielding the largest changes in model predictions as measured by the Nash-Sutcliffe criterion. A Bayesian hierarchical model is then formulated to explicitly differentiate between forcing, response and model error. It provides a very general framework for calibration and prediction, as well as for testing hypotheses regarding model structure and data uncertainty. A case study calibrating a six-parameter CRR model to daily data from the Abercrombie catchment (Australia) demonstrates the considerable potential of this approach. Allowing storm-dependent variation in just two model parameters (with one of the parameters characterising model error and the other reflecting input uncertainty) yields a substantially improved model fit raising the Nash-Sutcliffe statistic from 0.74 to 0.94. Of particular significance is the use of posterior diagnostics to test the key assumptions about the data and model errors

  8. Exploring the effect of spatial disaggregation of conceptual hydrologic models for improved flow forecasting

    NASA Astrophysics Data System (ADS)

    Wi, S.; Brown, C. M.

    2013-12-01

    The availability of gridded climatic data, high resolution Digital Elevation Maps (DEM), soil, land-use and land-cover data has motivated researchers to exploit these data for more accurate distributed hydrologic modeling. However, with increased disaggregation there is the introduction of numerous parameters and conceptualized processes that are unobservable. In this study we explore the advantage of employing spatially distributed climatic and geographic information in the context of a disaggregated conceptual hydrologic modeling framework by developing distributed model versions for three hydrologic models: HYMOD (Hydrologic Model), HBV (Hydrologiska Byrans Vattenbalansavdelning), and SAC-SMA (Sacramento Soil Moisture Accounting). This study proposes a general framework for building a distributed conceptual hydrological model by coupling a rainfall-runoff model to a routing model which is based on the formularized sub-basin unit hydrograph and the linearized Saint-Venant equation. To deal with a very large number of model parameters resulting from the distributed system modeling approach, hydrological similarity and landscape classification derived from the geospatial database is used to reduce the complexity in the process of model parameter estimation. Tests for the Iowa River basin show that three distributed models outperform lumped model versions in terms of reproducing observed streamflow for both calibration and validation periods. Model calibration strategies informed by geospatial information yield flow predictions comparable to the fully distributed model simulations. Results from this study are encouraging and indicate that the proposed framework holds promise for making improved predictions of hydrologic system response.

  9. GEOQUÌMICO : an interactive tool for comparing sorption conceptual models (surface complexation modeling verus K[D]).

    SciTech Connect

    Hammond, Glenn E.; Cygan, Randall Timothy

    2007-11-01

    Within reactive geochemical transport, several conceptual models exist for simulating sorption processes in the subsurface. Historically, the K{sub D} approach has been the method of choice due to ease of implementation within a reactive transport model and straightforward comparison with experimental data. However, for modeling complex sorption phenomenon (e.g. sorption of radionuclides onto mineral surfaces), this approach does not systematically account for variations in location, time, or chemical conditions, and more sophisticated methods such as a surface complexation model (SCM) must be utilized. It is critical to determine which conceptual model to use; that is, when the material variation becomes important to regulatory decisions. The geochemical transport tool GEOQUIMICO has been developed to assist in this decision-making process. GEOQUIMICO provides a user-friendly framework for comparing the accuracy and performance of sorption conceptual models. The model currently supports the K{sub D} and SCM conceptual models. The code is written in the object-oriented Java programming language to facilitate model development and improve code portability. The basic theory underlying geochemical transport and the sorption conceptual models noted above is presented in this report. Explanations are provided of how these physicochemical processes are instrumented in GEOQUIMICO and a brief verification study comparing GEOQUIMICO results to data found in the literature is given.

  10. Computer-based creativity enhanced conceptual design model for non-routine design of mechanical systems

    NASA Astrophysics Data System (ADS)

    Li, Yutong; Wang, Yuxin; Duffy, Alex H. B.

    2014-11-01

    Computer-based conceptual design for routine design has made great strides, yet non-routine design has not been given due attention, and it is still poorly automated. Considering that the function-behavior-structure(FBS) model is widely used for modeling the conceptual design process, a computer-based creativity enhanced conceptual design model(CECD) for non-routine design of mechanical systems is presented. In the model, the leaf functions in the FBS model are decomposed into and represented with fine-grain basic operation actions(BOA), and the corresponding BOA set in the function domain is then constructed. Choosing building blocks from the database, and expressing their multiple functions with BOAs, the BOA set in the structure domain is formed. Through rule-based dynamic partition of the BOA set in the function domain, many variants of regenerated functional schemes are generated. For enhancing the capability to introduce new design variables into the conceptual design process, and dig out more innovative physical structure schemes, the indirect function-structure matching strategy based on reconstructing the combined structure schemes is adopted. By adjusting the tightness of the partition rules and the granularity of the divided BOA subsets, and making full use of the main function and secondary functions of each basic structure in the process of reconstructing of the physical structures, new design variables and variants are introduced into the physical structure scheme reconstructing process, and a great number of simpler physical structure schemes to accomplish the overall function organically are figured out. The creativity enhanced conceptual design model presented has a dominant capability in introducing new deign variables in function domain and digging out simpler physical structures to accomplish the overall function, therefore it can be utilized to solve non-routine conceptual design problem.

  11. Life cycle of the marine alga Phaeocystis: A conceptual model to summarize literature and guide research

    NASA Astrophysics Data System (ADS)

    Whipple, Stuart J.; Patten, Bernard C.; Verity, Peter G.

    2005-08-01

    This paper reviews literature on the life cycle of the marine algal genus Phaeocystis, and organizes existing information in the form of a qualitative conceptual model of life-cycle stages, stage transitions, ecosystem inputs and outputs, and internal and external controlling factors. Conceptualization is the first phase of modeling, typically continued in later quantitative phases by mathematical formulation, calibration of parameters, dynamic simulation, and different forms of systems analysis. Qualitative conceptualization can also promote multidisciplinary interactions and structure early stages of scientific inquiry. To exploit the qualitative benefits of conceptual modeling, the goals of this paper are to: (1) review the literature of Phaeocystis life-cycle biology and ecology; (2) from the material of this review, construct, a conceptual life-cycle model covering all Phaeocystis species; and (3) show how this model, a platform for further quantitative development, is also used as a qualitative tool to guide empirical research. The conceptual model includes known and putative life-cycle stages, colony size classes, and genetic, physiological, semiotic, and ecological information expressed or potentially expressed across the genus. It consists of 15 compartments. Seven are single-celled: Solitary Diploid Flagellates ( x1), Solitary Diploid Non-flagellates ( x2), Benthic Solitary Diploid Non-Flagellates ( x3), Solitary Diploid Flagellated Macrozoospores ( x8), Solitary Haploid Flagellated Microzoospores ( x9), Solitary Haploid Microflagellates ( x10), and Solitary Haploid Mesoflagellates ( x11). The remaining eight compartments represent the New stage, and Small, Medium, and Large size classes of Healthy/Growing Colonies ( x4- x7), and Senescent/Declining Colonies ( x12- x15). Six flow types interconnect the compartments: (a) physical transport, (b) solitary cell transformations, (c) solitary cell↔colony transitions, (d) colony growth and differentiation, (e

  12. Advanced conceptual design report for the Z-Beamlet laser backlighter

    SciTech Connect

    Caird, J

    1999-05-31

    The Z-accelerator facility at Sandia National Laboratories (SNL) in Albuquerque, New Mexico, performs critical experiments on the physics of matter at extremely high energy density as part of the Department of Energy's nuclear weapons Stockpile Stewardship Program. In order to augment and enhance the value of experiments performed at this facility, the construction of a new x-ray backlighting diagnostic system is required. New information would be obtained by recording images and/or spectra of x-ray radiation transmitted through target materials as they evolve during Z-accelerator-driven experiments (or ''shots''). In this application, we generally think of the diagnostic x-rays as illumination produced behind the target materials and detected after passing through the Z-target. Hence the x-ray source is commonly called a ''backlighter.'' The methodology is a specific implementation of the general science known as x-ray radiography and/or x-ray spectroscopy. X-ray backlighter experiments have been performed in inertial confinement fusion (ICF) facilities in many countries. On Nova, experience with backlighters has been obtained since about 1986. An intense source of x-rays is produced by focusing one of its beams on a backlighter target nearby, while the other beams are used to create the high-energy-density conditions to be studied in the experiment. This conceptual design report describes how a laser-backlighter similar to one beam of Nova could be constructed for use at Sandia's Z-accelerator facility. The development of such a facility at Sandia is timely for two major reasons. First, at LLNL the Beamlet laser was decommissioned in FY98, and the Nova laser will be decommissioned in FY99, in preparation for activation of the National Ignition Facility (NIF). This will provide several million dollars worth of subsystems and components from which to construct other lasers, such as the Z-backlighter. Second, the new diagnostic capability at Sandia will provide a

  13. Modeling of Spacecraft Advanced Chemical Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Benfield, Michael P. J.; Belcher, Jeremy A.

    2004-01-01

    This paper outlines the development of the Advanced Chemical Propulsion System (ACPS) model for Earth and Space Storable propellants. This model was developed by the System Technology Operation of SAIC-Huntsville for the NASA MSFC In-Space Propulsion Project Office. Each subsystem of the model is described. Selected model results will also be shown to demonstrate the model's ability to evaluate technology changes in chemical propulsion systems.

  14. A cognitive model of second-year organic chemistry students' conceptualizations of mental molecular rotation

    NASA Astrophysics Data System (ADS)

    Briggs, Michael W.

    The goal of this research was to answer the question, "What is a plausible explanation (model) of the cognitive structure and processes that facilitate mental molecular rotation?". This work used phenomenographic methodology and techniques of interview and think-aloud protocol. Constructivism was the theoretical framework. At the outset of the research, I designed nine tasks to obtain participant articulations of conceptualizations of mental molecular rotations. Articulations from five second-year organic chemistry students attending a Midwestern research university became the research data. Analysis produced four emerging themes along two axes: visualization representation and modeling cognition. These two axes formed a mental space, which was modeled by structure and processes that facilitated mental molecular rotation. A theoretical cognitive model of mental molecular rotation was based on the work of two researchers: Robbie Case and Richard Lesh. Lesh's "mental model" is composed of cognitive elements and operations, which are distributed over heeded local and global cognitive sub-models whereas Case deals with unheeded central conceptual structures. The models and structures interact to produce new knowledge and facilitate the use of existing knowledge. Two predictions of the theory of mental molecular rotation were elaborated. Students without a set of operations in a central conceptual structure will not be able to mentally rotate molecules. This is true even if a set of components, other than "operation", is constructed. The artifacts of mental molecular rotation can be used to determine the state of construction of the central conceptual structure responsible for mental molecular rotation.

  15. Advanced turbine systems phase II - conceptual design and product development. Final report, August 1993--July 1996

    SciTech Connect

    1996-10-01

    The National Energy Strategy (NES) calls for a balanced program of greater energy efficiency, use of alternative fuels, and the environmentally responsible development of all U.S. energy resources. Consistent with the NES, a Department of Energy (DOE) program has been created to develop Advanced Turbine Systems (ATS). The technical ATS requirements are based upon two workshops held in Greenville, SC that were sponsored by DOE and hosted by Clemson University. The objective of this 8-year program, managed jointly by DOE`s Office of Fossil Energy, and, Office of Conservation and Renewable Energy, is to develop natural-gas-fired base load power plants that will have cycle efficiencies greater than 60%, lower heating value (LHV), be environmentally superior to current technology, and also be cost competitive. The program will include work to transfer advanced technology to the coal- and biomass-fueled systems being developed in other DOE programs.

  16. 7-GeV Advanced Photon Source Instrumentation Initiative conceptual design report

    SciTech Connect

    Not Available

    1992-12-01

    In this APS Instrumentation Initiative, 2.5-m-long and 5-m-long insertion-device x-ray sources will be built on 9 straight sections of the APS storage ring, and an additional 9 bending-magnet sources will also be put in use. The front ends for these 18 x-ray sources will be built to contain and safeguard access to these bright x-ray beams. In addition, funds will be provided to build state-of-the-art insertion-device beamlines to meet scientific and technological research demands well into the next century. This new initiative will also include four user laboratory modules and a special laboratory designed to meet the x-ray imaging research needs of the users. The Conceptual Design Report (CDR) for the APS Instrumentation Initiative describes the scope of all the above technical and conventional construction and provides a detailed cost and schedule for these activities. According to these plans, this new initiative begins in FY 1994 and ends in FY 1998. The document also describes the preconstruction R D plans for the Instrumentation Initiative activities and provides the cost estimates for the required R D.

  17. 7-GeV Advanced Photon Source Instrumentation Initiative conceptual design report

    SciTech Connect

    Not Available

    1992-12-01

    In this APS Instrumentation Initiative, 2.5-m-long and 5-m-long insertion-device x-ray sources will be built on 9 straight sections of the APS storage ring, and an additional 9 bending-magnet sources will also be put in use. The front ends for these 18 x-ray sources will be built to contain and safeguard access to these bright x-ray beams. In addition, funds will be provided to build state-of-the-art insertion-device beamlines to meet scientific and technological research demands well into the next century. This new initiative will also include four user laboratory modules and a special laboratory designed to meet the x-ray imaging research needs of the users. The Conceptual Design Report (CDR) for the APS Instrumentation Initiative describes the scope of all the above technical and conventional construction and provides a detailed cost and schedule for these activities. According to these plans, this new initiative begins in FY 1994 and ends in FY 1998. The document also describes the preconstruction R&D plans for the Instrumentation Initiative activities and provides the cost estimates for the required R&D.

  18. Advanced turbine systems program -- Conceptual design and product development. Final report

    SciTech Connect

    1996-07-26

    This Final Technical Report presents the accomplishments on Phase 2 of the Advanced Turbine Systems (ATS). The ATS is an advanced, natural gas fired gas turbine system that will represent a major advance on currently available industrial gas turbines in the size range of 1--20 MW. This report covers a market-driven development. The Market Survey reported in Section 5 identified the customer`s performance needs. This market survey used analyses performed by Solar turbine Incorporated backed up by the analyses done by two consultants, Research Decision Consultants (RDC) and Onsite Energy Corporation (Onsite). This back-up was important because it is the belief of all parties that growth of the ATS will depend both on continued participation in Solar`s traditional oil and gas market but to a major extent on a new market. This new market is distributed electrical power generation. Difficult decisions have had to be made to meet the different demands of the two markets. Available resources, reasonable development schedules, avoidance of schedule or technology failures, probable acceptance by the marketplace, plus product cost, performance and environmental friendliness are a few of the complex factors influencing the selection of the Gas Fired Advanced Turbine System described in Section 3. Section 4 entitled ``Conversion to Coal`` was a task which addresses the possibility of a future interruption to an economic supply of natural gas. System definition and analysis is covered in Section 6. Two major objectives were met by this work. The first was identification of those critical technologies that can support overall attainment of the program goals. Separate technology or component programs were begun to identify and parameterize these technologies and are described in Section 7. The second objective was to prepare parametric analyses to assess performance sensitivity to operating variables and to select design approaches to meet the overall program goals.

  19. A conceptual data model and modelling language for fields and agents

    NASA Astrophysics Data System (ADS)

    de Bakker, Merijn; de Jong, Kor; Schmitz, Oliver; Karssenberg, Derek

    2016-04-01

    Modelling is essential in order to understand environmental systems. Environmental systems are heterogeneous because they consist of fields and agents. Fields have a value defined everywhere at all times, for example surface elevation and temperature. Agents are bounded in space and time and have a value only within their bounds, for example biomass of a tree crown or the speed of a car. Many phenomena have properties of both fields and agents. Although many systems contain both fields and agents and integration of these concepts would be required for modelling, existing modelling frameworks concentrate on either agent-based or field-based modelling and are often low-level programming frameworks. A concept is lacking that integrates fields and agents in a way that is easy to use for modelers who are not software engineers. To address this issue, we develop a conceptual data model that represents fields and agents uniformly. We then show how the data model can be used in a high-level modelling language. The data model represents fields and agents in space-time. Also relations and networks can be represented using the same concepts. Using the conceptual data model we can represent static and mobile agents that may have spatial and temporal variation within their extent. The concepts we use are phenomenon, property set, item, property, domain and value. The phenomenon is the thing that is modelled, which can be any real world thing, for example trees. A phenomenon usually consists of several items, e.g. single trees. The domain is the spatiotemporal location and/or extent for which the items in the phenomenon are defined. Multiple different domains can coexist for a given phenomenon. For example a domain describing the extent of the trees and a domain describing the stem locations. The same goes for the property, which is an attribute of the thing that is being modeled. A property has a value, which is possibly discretized, for example the biomass over the tree crown

  20. On the Performance of Alternate Conceptual Ecohydrological Models for Streamflow Prediction

    NASA Astrophysics Data System (ADS)

    Naseem, Bushra; Ajami, Hoori; Cordery, Ian; Sharma, Ashish

    2016-04-01

    A merging of a lumped conceptual hydrological model with two conceptual dynamic vegetation models is presented to assess the performance of these models for simultaneous simulations of streamflow and leaf area index (LAI). Two conceptual dynamic vegetation models with differing representation of ecological processes are merged with a lumped conceptual hydrological model (HYMOD) to predict catchment scale streamflow and LAI. The merged RR-LAI-I model computes relative leaf biomass based on transpiration rates while the RR-LAI-II model computes above ground green and dead biomass based on net primary productivity and water use efficiency in response to soil moisture dynamics. To assess the performance of these models, daily discharge and 8-day MODIS LAI product for 27 catchments of 90 - 1600km2 in size located in the Murray - Darling Basin in Australia are used. Our results illustrate that when single-objective optimisation was focussed on maximizing the objective function for streamflow or LAI, the other un-calibrated predicted outcome (LAI if streamflow is the focus) was consistently compromised. Thus, single-objective optimization cannot take into account the essence of all processes in the conceptual ecohydrological models. However, multi-objective optimisation showed great strength for streamflow and LAI predictions. Both response outputs were better simulated by RR-LAI-II than RR-LAI-I due to better representation of physical processes such as net primary productivity (NPP) in RR-LAI-II. Our results highlight that simultaneous calibration of streamflow and LAI using a multi-objective algorithm proves to be an attractive tool for improved streamflow predictions.

  1. Conceptual groundwater flow models identified in triassic basins, eastern united states

    NASA Astrophysics Data System (ADS)

    Venkatakrishnan, R.; Gheorghiu, F.

    2003-04-01

    Identification of a conceptual groundwater flow model is an important step in planning appropriate groundwater investigations for the accurate delineation of contaminated sites. Development of a conceptual groundwater flow model early in the process of defining groundwater impacts can save resources and minimize the potential for erroneous interpretations resulting in potentially flawed remedial designs. This study presents typical groundwater flow models identified in several Triassic Basins that occur as half-graben along the eastern seaboard of the United States. Groundwater flow in the Triassic sedimentary rocks has local and regional components. Shallow groundwater discharges locally to nearby streams. Deeper, regional groundwater flow is toward points of regional groundwater discharge, generally higher order stream courses. The hydrogeologic regime within the basins is characterized by fractured, bedded sedimentary sequences with groundwater occuring under both unconfined, water table and confined conditions. Inherent controls on groundwater flow are a combination of the interaction of factors that include topography, stratal geometry and lithology, the distribution and intensity of fractures, presence of diabase intrusions, basalt flows, and weathering processes of the bedrock materials. The main groups of conceptual groundwater flow models identified in the Triassic Basins include: (i) structural control flow models (i.e., bedding strike, bedding dip, basalt cooling fractures, major joint sets and faults), (ii) lithologic control flow models (i.e., top of rock weathered zone, basalt flow top weathering, diabase dikes, lopolith containment), and, (iii) topographic control, and (iv) combinations of above. The identification of these distinct groundwater flow conceptual models is possible based on numerous investigations focused on environmental issues conducted in Connecticut, New Jersey, Pennsylvania, Virginia, and North Carolina. The typical conceptual

  2. An independent verification and validation of the Future Theater Level Model conceptual model

    SciTech Connect

    Hartley, D.S. III; Kruse, K.L.; Martellaro, A.J.; Packard, S.L.; Thomas, B. Jr.; Turley, V.K.

    1994-08-01

    This report describes the methodology and results of independent verification and validation performed on a combat model in its design stage. The combat model is the Future Theater Level Model (FTLM), under development by The Joint Staff/J-8. J-8 has undertaken its development to provide an analysis tool that addresses the uncertainties of combat more directly than previous models and yields more rapid study results. The methodology adopted for this verification and validation consisted of document analyses. Included were detailed examination of the FTLM design documents (at all stages of development), the FTLM Mission Needs Statement, and selected documentation for other theater level combat models. These documents were compared to assess the FTLM as to its design stage, its purpose as an analytical combat model, and its capabilities as specified in the Mission Needs Statement. The conceptual design passed those tests. The recommendations included specific modifications as well as a recommendation for continued development. The methodology is significant because independent verification and validation have not been previously reported as being performed on a combat model in its design stage. The results are significant because The Joint Staff/J-8 will be using the recommendations from this study in determining whether to proceed with develop of the model.

  3. Conceptual design of a fast-ion D-alpha diagnostic on experimental advanced superconducting tokamak

    SciTech Connect

    Huang, J. Wan, B.; Hu, L.; Hu, C.; Heidbrink, W. W.; Zhu, Y.; Hellermann, M. G. von; Gao, W.; Wu, C.; Li, Y.; Fu, J.; Lyu, B.; Yu, Y.; Ye, M.; Shi, Y.

    2014-11-15

    To investigate the fast ion behavior, a fast ion D-alpha (FIDA) diagnostic system has been planned and is presently under development on Experimental Advanced Superconducting Tokamak. The greatest challenges for the design of a FIDA diagnostic are its extremely low intensity levels, which are usually significantly below the continuum radiation level and several orders of magnitude below the bulk-ion thermal charge-exchange feature. Moreover, an overlaying Motional Stark Effect (MSE) feature in exactly the same wavelength range can interfere. The simulation of spectra code is used here to guide the design and evaluate the diagnostic performance. The details for the parameters of design and hardware are presented.

  4. Conceptual design of a fast-ion D-alpha diagnostic on experimental advanced superconducting tokamak

    NASA Astrophysics Data System (ADS)

    Huang, J.; Heidbrink, W. W.; Wan, B.; von Hellermann, M. G.; Zhu, Y.; Gao, W.; Wu, C.; Li, Y.; Fu, J.; Lyu, B.; Yu, Y.; Shi, Y.; Ye, M.; Hu, L.; Hu, C.

    2014-11-01

    To investigate the fast ion behavior, a fast ion D-alpha (FIDA) diagnostic system has been planned and is presently under development on Experimental Advanced Superconducting Tokamak. The greatest challenges for the design of a FIDA diagnostic are its extremely low intensity levels, which are usually significantly below the continuum radiation level and several orders of magnitude below the bulk-ion thermal charge-exchange feature. Moreover, an overlaying Motional Stark Effect (MSE) feature in exactly the same wavelength range can interfere. The simulation of spectra code is used here to guide the design and evaluate the diagnostic performance. The details for the parameters of design and hardware are presented.

  5. Conceptual design of a fast-ion D-alpha diagnostic on experimental advanced superconducting tokamak.

    PubMed

    Huang, J; Heidbrink, W W; Wan, B; von Hellermann, M G; Zhu, Y; Gao, W; Wu, C; Li, Y; Fu, J; Lyu, B; Yu, Y; Shi, Y; Ye, M; Hu, L; Hu, C

    2014-11-01

    To investigate the fast ion behavior, a fast ion D-alpha (FIDA) diagnostic system has been planned and is presently under development on Experimental Advanced Superconducting Tokamak. The greatest challenges for the design of a FIDA diagnostic are its extremely low intensity levels, which are usually significantly below the continuum radiation level and several orders of magnitude below the bulk-ion thermal charge-exchange feature. Moreover, an overlaying Motional Stark Effect (MSE) feature in exactly the same wavelength range can interfere. The simulation of spectra code is used here to guide the design and evaluate the diagnostic performance. The details for the parameters of design and hardware are presented.

  6. The Conceptual Framework of Factors Affecting Shared Mental Model

    ERIC Educational Resources Information Center

    Lee, Miyoung; Johnson, Tristan; Lee, Youngmin; O'Connor, Debra; Khalil, Mohammed

    2004-01-01

    Many researchers have paid attention to the potentiality and possibility of the shared mental model because it enables teammates to perform their job better by sharing team knowledge, skills, attitudes, dynamics and environments. Even though theoretical and experimental evidences provide a close relationship between the shared mental model and…

  7. Conceptual Models To Study the Adaptation of the Oldest Old.

    ERIC Educational Resources Information Center

    Martin, Peter

    In recent years there has been an increased awareness about the growing number of the oldest old. A structural model for the study of the oldest old was introduced by Lehr (1987) and was built on experience with data from the Bonn Longitudinal Study of Aging. In the Lehr model, genetic, environmental, and ecological factors affect longevity…

  8. Characteristics and Conceptual Framework of the Easy-Play Model

    ERIC Educational Resources Information Center

    Lu, Chunlei; Steele, Kyle

    2014-01-01

    The Easy-Play Model offers a defined framework to organize games that promote an inclusive and enjoyable sport experience. The model can be implemented by participants playing sports in educational, recreational or social contexts with the goal of achieving an active lifestyle in an inclusive, cooperative and enjoyable environment. The Easy-Play…

  9. The Hourglass Approach: A Conceptual Model for Group Facilitators.

    ERIC Educational Resources Information Center

    Kriner, Lon S.; Goulet, Everett F.

    1983-01-01

    Presents a model to clarify the facilitator's role in working with groups. The Hourglass Approach model incorporates Carkhuff's empathetic levels of communication and Schultz's theory of personality. It is designed to be a systematic and comprehensive method usable with a variety of counseling approaches in all types of groups. (JAC)

  10. A conceptual model for culture change evaluation in nursing homes.

    PubMed

    Hartmann, Christine W; Snow, A Lynn; Allen, Rebecca S; Parmelee, Patricia A; Palmer, Jennifer A; Berlowitz, Dan

    2013-01-01

    This article describes the development and particulars of a new, comprehensive model of nursing home culture change, the Nursing Home Integrated Model for Producing and Assessing Cultural Transformation (Nursing Home IMPACT). This model is structured into four categories, "meta constructs," "care practices," "workplace practices," and "environment of care," with multiple domains under each. It includes detailed, triangulated assessment methods capturing various stakeholder perspectives for each of the model's domains. It is hoped that this model will serve two functions: first, to help practitioners guide improvements in resident care by identifying particular areas in which culture change is having positive effects, as well as areas that could benefit from modification; and second, to emphasize the importance in culture change of the innumerable perspectives of residents, family members, staff, management, and leadership. PMID:23850129

  11. Conceptual models for implementing biopsychosocial theory in clinical practice.

    PubMed

    Jones, M; Edwards, I; Gifford, L

    2002-02-01

    The integration of the biopsychosocial model into manual therapy practice is challenging for clinicians, especially for those who have not received formal training in biopsychosocial theory or its application. In this masterclass two contemporary models of health and disability are presented along with a model for organizing clinical knowledge, and a model of reasoning strategies that will assist clinicians in their understanding and application of biopsychosocial theory. All four models emphasise the importance of understanding and managing both the psychosocial and the biomedical aspects of patients' problems. Facilitating change in patients' (and clinicians') perspectives on pain and its biopsychosocial influences requires them to reflect on their underlying assumptions and the basis of those beliefs. Through this reflective process perspectives will be transformed, and for clinicians, in time, different management practices will emerge.

  12. Integrating O/S models during conceptual design, part 2

    NASA Technical Reports Server (NTRS)

    Ebeling, Charles E.

    1994-01-01

    This report documents the procedures for utilizing and maintaining the Reliability & Maintainability Model (RAM) developed by the University of Dayton for the National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC) under NASA research grant NAG-1-1327. The purpose of the grant is to provide support to NASA in establishing operational and support parameters and costs of proposed space systems. As part of this research objective, the model described here was developed. Additional documentation concerning the development of this model may be found in Part 1 of this report. This is the 2nd part of a 3 part technical report.

  13. Advanced Space Shuttle simulation model

    NASA Technical Reports Server (NTRS)

    Tatom, F. B.; Smith, S. R.

    1982-01-01

    A non-recursive model (based on von Karman spectra) for atmospheric turbulence along the flight path of the shuttle orbiter was developed. It provides for simulation of instantaneous vertical and horizontal gusts at the vehicle center-of-gravity, and also for simulation of instantaneous gusts gradients. Based on this model the time series for both gusts and gust gradients were generated and stored on a series of magnetic tapes, entitled Shuttle Simulation Turbulence Tapes (SSTT). The time series are designed to represent atmospheric turbulence from ground level to an altitude of 120,000 meters. A description of the turbulence generation procedure is provided. The results of validating the simulated turbulence are described. Conclusions and recommendations are presented. One-dimensional von Karman spectra are tabulated, while a discussion of the minimum frequency simulated is provided. The results of spectral and statistical analyses of the SSTT are presented.

  14. Hydrogeologic setting and conceptual hydrologic model of the Spring Creek basin, Centre County, Pennsylvania

    USGS Publications Warehouse

    Fulton, John W.; Koerkle, Edward H.; McAuley, Steven D.; Hoffman, Scott A.; Zarr, Linda F.

    2005-01-01

    The Spring Creek Basin, Centre County, Pa., is experiencing some of the most rapid growth and development within the Commonwealth. This trend has resulted in land-use changes and increased water use, which will affect the quantity and quality of stormwater runoff, surface water, ground water, and aquatic resources within the basin. The U.S. Geological Survey (USGS), in cooperation with the ClearWater Conservancy (CWC), Spring Creek Watershed Community (SCWC), and Spring Creek Watershed Commission (SCWCm), has developed a Watershed Plan (Plan) to assist decision makers in water-resources planning. One element of the Plan is to provide a summary of the basin characteristics and a conceptual model that incorporates the hydrogeologic characteristics of the basin. The report presents hydrogeologic data for the basin and presents a conceptual model that can be used as the basis for simulating surface-water and ground-water flow within the basin. Basin characteristics; sources of data referenced in this text; physical characteristics such as climate, physiography, topography, and land use; hydrogeologic characteristics; and water-quality characteristics are discussed. A conceptual model is a simplified description of the physical components and interaction of the surface- and ground-water systems. The purpose for constructing a conceptual model is to simplify the problem and to organize the available data so that the system can be analyzed accurately. Simplification is necessary, because a complete accounting of a system, such as Spring Creek, is not possible. The data and the conceptual model could be used in development of a fully coupled numerical model that dynamically links surface water, ground water, and land-use changes. The model could be used by decision makers to manage water resources within the basin and as a prototype that is transferable to other watersheds.

  15. Micromechanical modeling of advanced materials

    SciTech Connect

    Silling, S.A.; Taylor, P.A.; Wise, J.L.; Furnish, M.D.

    1994-04-01

    Funded as a laboratory-directed research and development (LDRD) project, the work reported here focuses on the development of a computational methodology to determine the dynamic response of heterogeneous solids on the basis of their composition and microstructural morphology. Using the solid dynamics wavecode CTH, material response is simulated on a scale sufficiently fine to explicitly represent the material`s microstructure. Conducting {open_quotes}numerical experiments{close_quotes} on this scale, the authors explore the influence that the microstructure exerts on the material`s overall response. These results are used in the development of constitutive models that take into account the effects of microstructure without explicit representation of its features. Applying this methodology to a glass-reinforced plastic (GRP) composite, the authors examined the influence of various aspects of the composite`s microstructure on its response in a loading regime typical of impact and penetration. As a prerequisite to the microscale modeling effort, they conducted extensive materials testing on the constituents, S-2 glass and epoxy resin (UF-3283), obtaining the first Hugoniot and spall data for these materials. The results of this work are used in the development of constitutive models for GRP materials in transient-dynamics computer wavecodes.

  16. Modeling Advance Life Support Systems

    NASA Technical Reports Server (NTRS)

    Pitts, Marvin; Sager, John; Loader, Coleen; Drysdale, Alan

    1996-01-01

    Activities this summer consisted of two projects that involved computer simulation of bioregenerative life support systems for space habitats. Students in the Space Life Science Training Program (SLSTP) used the simulation, space station, to learn about relationships between humans, fish, plants, and microorganisms in a closed environment. One student complete a six week project to modify the simulation by converting the microbes from anaerobic to aerobic, and then balancing the simulation's life support system. A detailed computer simulation of a closed lunar station using bioregenerative life support was attempted, but there was not enough known about system restraints and constants in plant growth, bioreactor design for space habitats and food preparation to develop an integrated model with any confidence. Instead of a completed detailed model with broad assumptions concerning the unknown system parameters, a framework for an integrated model was outlined and work begun on plant and bioreactor simulations. The NASA sponsors and the summer Fell were satisfied with the progress made during the 10 weeks, and we have planned future cooperative work.

  17. Review of the dWind Model Conceptual Results

    SciTech Connect

    Baring-Gould, Ian; Gleason, Michael; Preus, Robert; Sigrin, Ben

    2015-09-16

    This presentation provides an overview of the dWind model, including its purpose, background, and current status. Baring-Gould presented this material as part of the September 2015 WINDExchange webinar.

  18. A Conceptual Model for the Translation of Bioethics Research and Scholarship.

    PubMed

    Mathews, Debra J H; Hester, D Micah; Kahn, Jeffrey; McGuire, Amy; McKinney, Ross; Meador, Keith; Philpott-Jones, Sean; Youngner, Stuart; Wilfond, Benjamin S

    2016-09-01

    While the bioethics literature demonstrates that the field has spent substantial time and thought over the last four decades on the goals, methods, and desired outcomes for service and training in bioethics, there has been less progress defining the nature and goals of bioethics research and scholarship. This gap makes it difficult both to describe the breadth and depth of these areas of bioethics and, importantly, to gauge their success. However, the gap also presents us with an opportunity to define this scope of work for ourselves and to help shape the broader conversation about the impact of academic research. Because of growing constraints on academic funding, researchers and scholars in many fields are being asked to demonstrate and also forecast the value and impact of their work. To do that, and also to satisfy ourselves that our work has meaningful effect, we must understand how our work can motivate change and how that change can be meaningfully measured. In a field as diverse as bioethics, the pathways to and metrics of change will likewise be diverse. It is therefore critical that any assessment of the impact of bioethics research and scholarship be informed by an understanding of the nature of the work, its goals, and how those goals can and ought to be furthered. In this paper, we propose a conceptual model that connects individual bioethics projects to the broader goals of scholarship, describing the translation of research and scholarly output into changes in thinking, practice, and policy. One of the key implications of the model is that impact in bioethics is generally the result of a collection of projects rather than of any single piece of research or scholarship. Our goal is to lay the groundwork for a thoroughgoing conversation about bioethics research and scholarship that will advance and shape the important conversation about their impact. PMID:27649827

  19. A conceptual model of the magnetic topology and nonlinear dynamics of ELMs

    NASA Astrophysics Data System (ADS)

    Evans, T. E.; Yu, J. H.; Jakubowski, M. W.; Schmitz, O.; Watkins, J. G.; Moyer, R. A.

    2009-06-01

    A conceptual model is introduced describing the 3D magnetic topology and nonlinear evolution of Type-I edge localized modes (ELMs), which immediately follow the initial linear peeling-ballooning growth phase. The model requires feedback amplification of stable and unstable invariant manifolds that increases the helical perturbation. The amplification process is caused by a rapid growth of field-aligned helical thermoelectric currents that flow through relatively short pedestal plasma flux tubes connecting the inner and outer divertor target plates. It is shown that the model qualitatively agrees with the formation of global field-aligned emission filaments and with fast IR heat flux splitting patterns of the inner and outer strike points observed experimentally. In addition, the model predicts an increase in the size of the ELMs as the pedestal collisionality drops. Experimental data and modeling results are presented supporting the basic conceptual elements of the model.

  20. Accurate mask model for advanced nodes

    NASA Astrophysics Data System (ADS)

    Zine El Abidine, Nacer; Sundermann, Frank; Yesilada, Emek; Ndiaye, El Hadji Omar; Mishra, Kushlendra; Paninjath, Sankaranarayanan; Bork, Ingo; Buck, Peter; Toublan, Olivier; Schanen, Isabelle

    2014-07-01

    Standard OPC models consist of a physical optical model and an empirical resist model. The resist model compensates the optical model imprecision on top of modeling resist development. The optical model imprecision may result from mask topography effects and real mask information including mask ebeam writing and mask process contributions. For advanced technology nodes, significant progress has been made to model mask topography to improve optical model accuracy. However, mask information is difficult to decorrelate from standard OPC model. Our goal is to establish an accurate mask model through a dedicated calibration exercise. In this paper, we present a flow to calibrate an accurate mask enabling its implementation. The study covers the different effects that should be embedded in the mask model as well as the experiment required to model them.

  1. Technology, Demographic Characteristics and E-Learning Acceptance: A Conceptual Model Based on Extended Technology Acceptance Model

    ERIC Educational Resources Information Center

    Tarhini, Ali; Elyas, Tariq; Akour, Mohammad Ali; Al-Salti, Zahran

    2016-01-01

    The main aim of this paper is to develop an amalgamated conceptual model of technology acceptance that explains how individual, social, cultural and organizational factors affect the students' acceptance and usage behaviour of the Web-based learning systems. More specifically, the proposed model extends the Technology Acceptance Model (TAM) to…

  2. A New Model to Facilitate Individualized Case Conceptualization and Treatment of Social Phobia: An Examination and Reaction to Moscovitch's Model

    ERIC Educational Resources Information Center

    Heimberg, Richard G.

    2009-01-01

    Moscovitch's (2009) model of social phobia is put forth as an integration and extension of previous cognitive-behavioral models. The author asserts that his approach overcomes a number of shortcomings of previous models and will serve to better guide case conceptualization, treatment planning, and intervention implementation for clients with…

  3. Empirical and Conceptual Problems With Longitudinal Trait-State Models: Introducing a Trait-State-Occasion Model

    ERIC Educational Resources Information Center

    Cole, David A.; Martin, Nina C.; Steiger, James H.

    2005-01-01

    The latent trait-state-error model (TSE) and the latent state-trait model with autoregression (LST-AR) represent creative structural equation methods for examining the longitudinal structure of psychological constructs. Application of these models has been somewhat limited by empirical or conceptual problems. In the present study, Monte Carlo…

  4. Purpose and Pedagogy: A Conceptual Model for an ePortfolio

    ERIC Educational Resources Information Center

    Buyarski, Catherine A.; Aaron, Robert W.; Hansen, Michele J.; Hollingsworth, Cynthia D.; Johnson, Charles A.; Kahn, Susan; Landis, Cynthia M.; Pedersen, Joan S.; Powell, Amy A.

    2015-01-01

    This conceptual model emerged from the need to balance multiple purposes and perspectives associated with developing an ePortfolio designed to promote student development and success. A comprehensive review of literature from various disciplines, theoretical frameworks, and scholarship, including self-authorship, reflection, ePortfolio pedagogy,…

  5. Cognitive Demand of Model Tracing Tutor Tasks: Conceptualizing and Predicting How Deeply Students Engage

    ERIC Educational Resources Information Center

    Kessler, Aaron M.; Stein, Mary Kay; Schunn, Christian D.

    2015-01-01

    Model tracing tutors represent a technology designed to mimic key elements of one-on-one human tutoring. We examine the situations in which such supportive computer technologies may devolve into mindless student work with little conceptual understanding or student development. To analyze the support of student intellectual work in the model…

  6. What Research Administrators Need to Know about Researcher Development: Towards a New Conceptual Model

    ERIC Educational Resources Information Center

    Evans, Linda

    2011-01-01

    Located within the recently emerged field of researcher development, this article represents an attempt to make a key theoretical contribution to its knowledge base through a conceptual analysis. It presents as propositional knowledge an original theoretical model of the componential structure of researcher development, as interpreted and defined…

  7. Stalking the "Big Picture"--or--the HRD Grid: A Conceptual Model for Human Resource Development.

    ERIC Educational Resources Information Center

    Trammell, Carmen

    1983-01-01

    This conceptual model is organized around these constructs: individual and organizational needs, management, employee, and cooperative initiatives. Appropriate activities have either a short-term focus (performance and productivity management) or a long-term focus (career management and organizational development). (CPAD Network, 1190 South…

  8. The Interactions between Problem Solving and Conceptual Change: System Dynamic Modelling as a Platform for Learning

    ERIC Educational Resources Information Center

    Lee, Chwee Beng

    2010-01-01

    This study examines the interactions between problem solving and conceptual change in an elementary science class where students build system dynamic models as a form of problem representations. Through mostly qualitative findings, we illustrate the interplay of three emerging intervening conditions (epistemological belief, structural knowledge…

  9. A Conceptual/Cross-cultural Model for Teaching Anthropology in the Elementary School.

    ERIC Educational Resources Information Center

    Dynneson, Thomas L.

    A conceptual/cross-cultural model, developed to help elementary teachers cope with the problems of initiating cultural, ethnic, or anthropology studies, is presented in five sections. (1) A brief description of the structure and methodology of anthropology defines in outline form the fields of cultural and social anthropology, physical…

  10. An Update on the Conceptual-Production Systems Model of Apraxia: Evidence from Stroke

    ERIC Educational Resources Information Center

    Stamenova, Vessela; Black, Sandra E.; Roy, Eric A.

    2012-01-01

    Limb apraxia is a neurological disorder characterized by an inability to pantomime and/or imitate gestures. It is more commonly observed after left hemisphere damage (LHD), but has also been reported after right hemisphere damage (RHD). The Conceptual-Production Systems model (Roy, 1996) suggests that three systems are involved in the control of…

  11. A Conceptual Model for Teaching Critical Thinking in a Knowledge Economy

    ERIC Educational Resources Information Center

    Chadwick, Clifton

    2011-01-01

    Critical thinking, viewed as rational and analytic thinking, is crucial for participation in a knowledge economy and society. This article provides a brief presentation of the importance of teaching critical thinking in a knowledge economy; suggests a conceptual model for teaching thinking; examines research on the historical role of teachers in…

  12. Conceptual Resources for Constructing the Concepts of Electricity: The Role of Models, Analogies and Imagination

    ERIC Educational Resources Information Center

    Taber, Keith S.; de Trafford, Tom; Quail, Teresa

    2006-01-01

    The topic of electricity offers considerable challenge for the teacher hoping to provide students with an insight into scientific ways of thinking about circuits. The concepts used to make sense of electric circuits are abstract and students are expected to develop conceptual models of the relationship between non-observable qualities (current,…

  13. Measuring dreaming as a beyond waking experience in Rogers's conceptual model.

    PubMed

    Watson, J

    1999-07-01

    This article describes the development of an instrument, the Assessment of Dream Experience. This instrument was developed within the context of Rogers's conceptual model, the science of unitary human beings, and was designed to measure dreaming as a beyond waking experience. A detailed description of the instrument and its psychometric properties is presented. Recommendations for future use are provided.

  14. Conceptualizing Gifted Adolescent Girls Using the Bicultural Skills Model: Implications for School Counselors

    ERIC Educational Resources Information Center

    Pepperell, Jennifer L.; Rubel, Deborah J.; Maki, Laura A.

    2012-01-01

    In counseling research and practice gifted girls often lack identification as a cultural group with unique features. Yet, girls in this population have specific and distinct struggles, worldviews, and ways of navigating social and academic groups. The purpose of this conceptualization article is to apply the bicultural skills model to adolescent…

  15. Managing Higher Education in a Climate of Contraction: A Conceptual Model.

    ERIC Educational Resources Information Center

    Doyle, K. J.

    1980-01-01

    A conceptual framework for managing higher education during a period of no growth, based on a model developed for business organizations by Joseph Schumpeter, is examined. Five categories of innovations included: new products (courses), new methods (improving productivity), new markets (students), new productive factors (sources of income), and…

  16. Dixie Valley Engineered Geothermal System Exploration Methodology Project, Baseline Conceptual Model Report

    DOE Data Explorer

    Joe Iovenitti

    2013-05-15

    The Engineered Geothermal System (EGS) Exploration Methodology Project is developing an exploration approach for EGS through the integration of geoscientific data. The Project chose the Dixie Valley Geothermal System in Nevada as a field laboratory site for methodlogy calibration purposes because, in the public domain, it is a highly characterized geothermal systems in the Basin and Range with a considerable amount of geoscience and most importantly, well data. This Baseline Conceptual Model report summarizes the results of the first three project tasks (1) collect and assess the existing public domain geoscience data, (2) design and populate a GIS database, and (3) develop a baseline (existing data) geothermal conceptual model, evaluate geostatistical relationships, and generate baseline, coupled EGS favorability/trust maps from +1km above sea level (asl) to -4km asl for the Calibration Area (Dixie Valley Geothermal Wellfield) to identify EGS drilling targets at a scale of 5km x 5km. It presents (1) an assessment of the readily available public domain data and some proprietary data provided by Terra-Gen Power, LLC, (2) a re-interpretation of these data as required, (3) an exploratory geostatistical data analysis, (4) the baseline geothermal conceptual model, and (5) the EGS favorability/trust mapping. The conceptual model presented applies to both the hydrothermal system and EGS in the Dixie Valley region.

  17. Testing a Conceptual Model Related to Weight Perceptions, Physical Activity and Smoking in Adolescents

    ERIC Educational Resources Information Center

    Plotnikoff, Ronald C.; Bercovitz, Kim; Rhodes, Ryan E.; Loucaides, Constantinos A.; Karunamuni, Nandini

    2007-01-01

    The purpose of this study was to test a conceptual model based on theoretical and empirically supported relationships related to the influences of weight perceptions, weight concerns, desires to change weight, friends, age and location in relation to physical activity (PA) and smoking in adolescents. A total of 1242 males and 1446 females (mean…

  18. Pathways to Life Success: A Conceptual Model of Financial Well-Being for Young Adults

    ERIC Educational Resources Information Center

    Shim, Soyeon; Xiao, Jing J.; Barber, Bonnie L.; Lyons, Angela C.

    2009-01-01

    The purpose of this study is to describe and test a conceptual model of the potential antecedents and consequences of financial well-being in young adulthood. Data (N = 781) were collected via an online survey conducted at a large state university in the southwestern United States. Our results suggest that self-actualizing personal values,…

  19. A Study to Determine the Mental Models in Preschool Children's Conceptualization of a Desert Environment

    ERIC Educational Resources Information Center

    Ahi, Berat

    2016-01-01

    This study aimed to determine mental models and identify codes (schemes) used in conceptualizing a desert environment. The sample for this study consisted of 184--out of a total population of 3,630--children in preschool education in the central district of Kastamonu, Turkey. Within the scope of this study, the children were initially asked to…

  20. The Development of a Conceptual Model of Student Satisfaction with Their Experience in Higher Education

    ERIC Educational Resources Information Center

    Douglas, Jacqueline; McClelland, Robert; Davies, John

    2008-01-01

    Purpose: The purpose of this paper is to introduce a conceptual model of student satisfaction with their higher education (HE) experience, based on the identification of the variable determinants of student perceived quality and the impact of those variables on student satisfaction and/or dissatisfaction with the overall student experience. The…

  1. The ISO Edi Conceptual Model Activity and Its Relationship to OSI.

    ERIC Educational Resources Information Center

    Fincher, Judith A.

    1990-01-01

    The edi conceptual model is being developed to define common structures, services, and processes that syntax-specific standards like X12 and EDIFACT could adopt. Open Systems Interconnection (OSI) is of interest to edi because of its potential to help enable global interoperability across Electronic Data Interchange (EDI) functional groups. A…

  2. College Men's Meanings of Masculinities and Contextual Influences: Toward a Conceptual Model

    ERIC Educational Resources Information Center

    Harris, Frank, III

    2010-01-01

    Based on a grounded theory study involving 68 male undergraduates, a conceptual model of the meanings college men ascribe to masculinities is proposed in this article. The participants equated masculinities with "being respected," "being confident and self-assured," "assuming responsibility," and "embodying physical prowess." Contextual factors…

  3. Teaching Conceptual Model-Based Word Problem Story Grammar to Enhance Mathematics Problem Solving

    ERIC Educational Resources Information Center

    Xin, Yan Ping; Wiles, Ben; Lin, Yu-Ying

    2008-01-01

    Borrowing the concept of story grammar from reading comprehension literature, the purpose of this study was to examine the effect of teaching "word problem (WP) story grammar" on arithmetic WP solving that emphasizes the algebraic expression of mathematical relations in conceptual models. Participants were five students in Grades 4 and 5 with or…

  4. A Conceptual Model and Assessment Template for Capacity Evaluation in Adult Guardianship

    ERIC Educational Resources Information Center

    Moye, Jennifer; Butz, Steven W.; Marson, Daniel C.; Wood, Erica

    2007-01-01

    Purpose: We develop a conceptual model and associated assessment template that is usable across state jurisdictions for evaluating the independent-living capacity of older adults in guardianship proceedings. Design and Methods: We used an iterative process in which legal provisions for guardianship and prevailing clinical practices for capacity…

  5. PIRPOSAL Model of Integrative STEM Education: Conceptual and Pedagogical Framework for Classroom Implementation

    ERIC Educational Resources Information Center

    Wells, John G.

    2016-01-01

    The PIRPOSAL model is both a conceptual and pedagogical framework intended for use as a pragmatic guide to classroom implementation of Integrative STEM Education. Designerly questioning prompted by a "need to know" serves as the basis for transitioning student designers within and among multiple phases while they progress toward an…

  6. Exploring the Postgraduate Research Climate and the Postgraduate Research Experience: A Conceptual Model

    ERIC Educational Resources Information Center

    Govender, K. K.

    2011-01-01

    The objective of this article is to develop a conceptual model aimed at improving the postgraduate research students' experience. Since postgraduate students "vote with their feet" an improved understanding of the postgraduate research service encounter may result in improving the quality of the encounter and so increasing throughput and the…

  7. Long-Term Conceptual Retrieval by College Biology Majors Following Model-Based Instruction

    ERIC Educational Resources Information Center

    Dauer, Joseph T.; Long, Tammy M.

    2015-01-01

    One of the goals of college-level introductory biology is to establish a foundation of knowledge and skills that can be built upon throughout a biology curriculum. In a reformed introductory biology course, we used iterative model construction as a pedagogical tool to promote students' understanding about conceptual connections, particularly those…

  8. Testing Conceptual Frameworks of Nonexperimental Program Evaluation Designs Using Structural Equation Modeling

    ERIC Educational Resources Information Center

    Adedokun, Omolola A.; Childress, Amy L.; Burgess, Wilella D.

    2011-01-01

    A theory-driven approach to evaluation (TDE) emphasizes the development and empirical testing of conceptual models to understand the processes and mechanisms through which programs achieve their intended goals. However, most reported applications of TDE are limited to large-scale experimental/quasi-experimental program evaluation designs. Very few…

  9. Hydrologic modelling for Lake Basaka: development and application of a conceptual water budget model.

    PubMed

    Dinka, Megersa O; Loiskandl, Willibald; Ndambuki, Julius M

    2014-09-01

    Quantification of fluxes of water into and out of terminal lakes like Basaka has fundamental challenges. This is due to the fact that accurate measurement and quantification of most of the parameters of a lake's hydrologic cycle are difficult. Furthermore, quantitative understanding of the hydrologic systems and hence, the data-intensive modelling is difficult in developing countries like Ethiopia due to limitation of sufficient recorded data. Therefore, formulation of a conceptual water balance model is extremely important as it presents a convenient analytical tool with simplified assumptions to simulate the magnitude of unknown fluxes. In the current study, a conceptual lake water balance model was systematically formulated, solved, calibrated, and validated successfully. Then, the surface water and groundwater interaction was quantified, and a mathematical relationship developed. The overall agreement between the observed and simulated lake stage at monthly time step was confirmed based on the standard performance parameters (R(2), MAE, RMSE, E(f)). The result showed that hydrological water balance of the lake is dominated by the groundwater (GW) component. The net GW flux in recent period (post-2000s) accounts about 56% of the total water inflow. Hence, GW plays a leading role in the hydrodynamics and existence of Lake Basaka and is mostly responsible for the expansion of the lake. Thus, identification of the potential sources/causes for the GW flux plays a leading role in order to limit the further expansion of the lake. Measurement of GW movement and exchange in the area is a high priority for future research. PMID:24816590

  10. Hydrologic modelling for Lake Basaka: development and application of a conceptual water budget model.

    PubMed

    Dinka, Megersa O; Loiskandl, Willibald; Ndambuki, Julius M

    2014-09-01

    Quantification of fluxes of water into and out of terminal lakes like Basaka has fundamental challenges. This is due to the fact that accurate measurement and quantification of most of the parameters of a lake's hydrologic cycle are difficult. Furthermore, quantitative understanding of the hydrologic systems and hence, the data-intensive modelling is difficult in developing countries like Ethiopia due to limitation of sufficient recorded data. Therefore, formulation of a conceptual water balance model is extremely important as it presents a convenient analytical tool with simplified assumptions to simulate the magnitude of unknown fluxes. In the current study, a conceptual lake water balance model was systematically formulated, solved, calibrated, and validated successfully. Then, the surface water and groundwater interaction was quantified, and a mathematical relationship developed. The overall agreement between the observed and simulated lake stage at monthly time step was confirmed based on the standard performance parameters (R(2), MAE, RMSE, E(f)). The result showed that hydrological water balance of the lake is dominated by the groundwater (GW) component. The net GW flux in recent period (post-2000s) accounts about 56% of the total water inflow. Hence, GW plays a leading role in the hydrodynamics and existence of Lake Basaka and is mostly responsible for the expansion of the lake. Thus, identification of the potential sources/causes for the GW flux plays a leading role in order to limit the further expansion of the lake. Measurement of GW movement and exchange in the area is a high priority for future research.

  11. Advanced Turbine Systems Program conceptual design and product development: Task 4.0

    SciTech Connect

    Not Available

    1994-06-01

    This Topical Report presents the results of Task 4 of the Westinghouse ATS Program. The purpose of Task 4 is to determine the technical development needs for conversion of the gas-fired ATS (GFATS). Two closely related, advanced, coal-based power plant technologies have been selected for consideration as the CFATS -- air-blown, coal gasification with hot gas cleaning incorporated into an Integrated Gasification Combined Cycle (IGCC), and the Second-Generation Pressurized Fluidized Bed Combustion (PFBC) combined cycle. These are described and their estimated performance and emissions in the CFATS are reported. A development program for the CFATS is described that focuses on major commercialization issues. These issues are in the areas of combustion, flow distribution, structural analysis, and materials selection.

  12. Conceptual hierarchical modeling to describe wetland plant community organization

    USGS Publications Warehouse

    Little, A.M.; Guntenspergen, G.R.; Allen, T.F.H.

    2010-01-01

    Using multivariate analysis, we created a hierarchical modeling process that describes how differently-scaled environmental factors interact to affect wetland-scale plant community organization in a system of small, isolated wetlands on Mount Desert Island, Maine. We followed the procedure: 1) delineate wetland groups using cluster analysis, 2) identify differently scaled environmental gradients using non-metric multidimensional scaling, 3) order gradient hierarchical levels according to spatiotem-poral scale of fluctuation, and 4) assemble hierarchical model using group relationships with ordination axes and post-hoc tests of environmental differences. Using this process, we determined 1) large wetland size and poor surface water chemistry led to the development of shrub fen wetland vegetation, 2) Sphagnum and water chemistry differences affected fen vs. marsh / sedge meadows status within small wetlands, and 3) small-scale hydrologic differences explained transitions between forested vs. non-forested and marsh vs. sedge meadow vegetation. This hierarchical modeling process can help explain how upper level contextual processes constrain biotic community response to lower-level environmental changes. It creates models with more nuanced spatiotemporal complexity than classification and regression tree procedures. Using this process, wetland scientists will be able to generate more generalizable theories of plant community organization, and useful management models. ?? Society of Wetland Scientists 2009.

  13. Nutrient supply and mercury dynamics in marine ecosystems: A conceptual model

    PubMed Central

    Chen, Celia Y.; Hammerschmidt, Chad R.; Mason, Robert P.; Gilmour, Cynthia C.; Sunderland, Elsie M.; Greenfield, Ben K.; Buckman, Kate L.; Lamborg, Carl H.

    2013-01-01

    There is increasing interest and concern over the impacts of mercury (Hg) inputs to marine ecosystems. One of the challenges in assessing these effects is that the cycling and trophic transfer of Hg are strongly linked to other contaminants and disturbances. In addition to Hg, a major problem facing coastal waters is the impacts of elevated nutrient, particularly nitrogen (N), inputs. Increases in nutrient loading alter coastal ecosystems in ways that should change the transport, transformations and fate of Hg, including increases in fixation of organic carbon and deposition to sediments, decreases in the redox status of sediments and changes in fish habitat. In this paper we present a conceptual model which suggests that increases in loading of reactive N to marine ecosystems might alter Hg dynamics, decreasing bioavailabilty and trophic transfer. This conceptual model is most applicable to coastal waters, but may also be relevant to the pelagic ocean. We present information from case studies that both support and challenge this conceptual model, including marine observations across a nutrient gradient; results of a nutrient-trophic transfer Hg model for pelagic and coastal ecosystems; observations of Hg species, and nutrients from coastal sediments in the northeastern U.S.; and an analysis of fish Hg concentrations in estuaries under different nutrient loadings. These case studies suggest that changes in nutrient loading can impact Hg dynamics in coastal and open ocean ecosystems. Unfortunately none of the case studies is comprehensive; each only addresses a portion of the conceptual model and has limitations. Nevertheless, our conceptual model has important management implications. Many estuaries near developed areas are impaired due to elevated nutrient inputs. Widespread efforts are underway to control N loading and restore coastal ecosystem function. An unintended consequence of nutrient control measures could be to exacerbate problems associated with Hg

  14. Understanding the nature of science through the historical development of conceptual models

    NASA Astrophysics Data System (ADS)

    Metz, Donald J.

    Understanding the nature of science has been a common goal in science education for years and continues to hold a distinct place in the recently developed Pan-Canadian science framework. Although the nature of science is often prominent in the front end of such reform documents, the implementation of these goals is presumed to be taught implicitly with the delivery of knowledge outcomes. Research strongly indicates that most students have naive conceptions about the nature of science. Surprisingly, research also clearly shows that science teachers do not fare much better, and that when they do possess adequate understanding of the nature of science it does not significantly influence their behaviour in the classroom. Norm Lederman (1998), one of the leading scholars in this field, describes two approaches advocated by curriculum reform documents to address the nature of science outcomes. The first approach suggests that students can achieve nature of science outcomes by "doing science", the second suggests that history of science can enhance students' understanding of the nature of science. While Lederman advocates the use of the history of science, he argues that these approaches are not effective when used implicitly. He recommends that an explicit approach be used (planned for, taught, assessed), but so far there have been no studies which employ this technique beyond short lessons or limited case histories. This thesis advocates an explicit approach to teaching the nature of science using the historical development of conceptual models. The research study of this thesis integrated the historical development of conceptual models with the traditional content found in a typical grade ten chemistry curriculum. Participants in the research were 74 senior 2 (grade 10) science students from four different classes in three different schools in the province of Manitoba. Prior to, and after instruction, students wrote Lederman's VNOS nature of science test. The tests

  15. The Historical Evolution of Theories and Conceptual Models for Nursing.

    ERIC Educational Resources Information Center

    Hawkins, Joellen W.

    The development of nursing models can be traced to the inception of nursing as a profession. Florence Nightingale laid the foundation for current nursing practice and differentiated nursing from medicine. The late 19th and early 20th centuries contributed a number of important nurse theorists, better known for other contributions to the neophyte…

  16. Toward a Conceptual Pattern in Librarianship: A Model.

    ERIC Educational Resources Information Center

    Nitecki, Joseph Z.

    1970-01-01

    In an attempt to import some concepts from general systems theory to the theory of librarianship, basic elements in the theory of librarianship were identified, interrelated in a form of a static model, and projected into a possible, dynamic pattern of change. (Author/LS)

  17. Preliminary Models of Conceptual Linkages among Proxemic Variables

    ERIC Educational Resources Information Center

    Evans, Gary W.; Eichelman, William

    1976-01-01

    Current models of human spatial behavior including stress, information overload, and micro-macro analysis are critically examined. An alternative functional orientation is developed which suggests that seeking to understand the adaptive value of various proxemic phenomena may provide some insight as to how the various proxemic variables are…

  18. Conceptual Complexity, Teaching Style and Models of Teaching.

    ERIC Educational Resources Information Center

    Joyce, Bruce; Weil, Marsha

    The focus of this paper is on the relative roles of personality and training in enabling teachers to carry out the kinds of complex learning models which are envisioned by curriculum reformers in the social sciences. The paper surveys some of the major research done in this area and concludes that: 1) Most teachers do not manifest the complex…

  19. Animation Model to Conceptualize ATP Generation: A Mitochondrial Oxidative Phosphorylation

    ERIC Educational Resources Information Center

    Jena, Ananta Kumar

    2015-01-01

    Adenosine triphosphate (ATP) is the molecular unit of intracellular energy and it is the product of oxidative phosphorylation of cellular respiration uses in cellular processes. The study explores the growth of the misconception levels amongst the learners and evaluates the effectiveness of animation model over traditional methods. The data…

  20. Conceptualizing Family Stress: A Systemic Revision of Hill's ABCX Model.

    ERIC Educational Resources Information Center

    Koch, Alberta Y.

    This report offers a theoretical approach to the study of family adaptation to stress. Major works pertaining to family theory, research, and stress, published since 1979, are explored as a theoretical framework, and three conclusions are drawn from these sources: (1) Hill's ABCX model of family stress still influences family stress research; (2)…

  1. Fostering Radical Conceptual Change through Dual-Situated Learning Model

    ERIC Educational Resources Information Center

    She, Hsiao-Ching

    2004-01-01

    This article examines how the Dual-Situated Learning Model (DSLM) facilitates a radical change of concepts that involve the understanding of matter, process, and hierarchical attributes. The DSLM requires knowledge of students' prior beliefs of science concepts and the nature of these concepts. In addition, DSLM also serves two functions: it…

  2. Conceptual Models and Theory-Embedded Principles on Effective Schooling.

    ERIC Educational Resources Information Center

    Scheerens, Jaap

    1997-01-01

    Reviews models and theories on effective schooling. Discusses four rationality-based organization theories and a fifth perspective, chaos theory, as applied to organizational functioning. Discusses theory-embedded principles flowing from these theories: proactive structuring, fit, market mechanisms, cybernetics, and self-organization. The…

  3. A Conceptual Model of Spirituality in Music Education

    ERIC Educational Resources Information Center

    van der Merwe, Liesl; Habron, John

    2015-01-01

    This article aims to describe the phenomenon of spirituality in music education by means of a model derived from the academic literature on the topic. Given the centrality of lived experience within this literature, we adopted a hermeneutic phenomenological theoretical framework to describe the phenomenon. The NCT (noticing, collecting, and…

  4. Clarifying the Conceptualization of Indicators within Different Models

    ERIC Educational Resources Information Center

    Wang, Jue; Engelhard, George, Jr.; Lu, Zhenqiu

    2014-01-01

    The authors of the focus article in this issue have emphasized the continuing confusion among some researchers regarding various indicators used in structural equation models (SEMs). Their major claim is that causal indicators are not inherently unstable, and even if they are unstable they are at least not more unstable than other types of…

  5. Integrating O/S models during conceptual design, part 3

    NASA Technical Reports Server (NTRS)

    Ebeling, Charles E.

    1994-01-01

    Space vehicles, such as the Space Shuttle, require intensive ground support prior to, during, and after each mission. Maintenance is a significant part of that ground support. All space vehicles require scheduled maintenance to ensure operability and performance. In addition, components of any vehicle are not one-hundred percent reliable so they exhibit random failures. Once detected, a failure initiates unscheduled maintenance on the vehicle. Maintenance decreases the number of missions which can be completed by keeping vehicles out of service so that the time between the completion of one mission and the start of the next is increased. Maintenance also requires resources such as people, facilities, tooling, and spare parts. Assessing the mission capability and resource requirements of any new space vehicle, in addition to performance specification, is necessary to predict the life cycle cost and success of the vehicle. Maintenance and logistics support has been modeled by computer simulation to estimate mission capability and resource requirements for evaluation of proposed space vehicles. The simulation was written with Simulation Language for Alternative Modeling II (SLAM II) for execution on a personal computer. For either one or a fleet of space vehicles, the model simulates the preflight maintenance checks, the mission and return to earth, and the post flight maintenance in preparation to be sent back into space. THe model enables prediction of the number of missions possible and vehicle turn-time (the time between completion of one mission and the start of the next) given estimated values for component reliability and maintainability. The model also facilitates study of the manpower and vehicle requirements for the proposed vehicle to meet its desired mission rate. This is the 3rd part of a 3 part technical report.

  6. A Conceptual Model for Extratropical Atmosphere-ocean Interaction

    NASA Astrophysics Data System (ADS)

    Zhao, B.; Reichler, T.

    2015-12-01

    Equipped with the current understanding for atmosphere-ocean interaction, we build a simple physically-based system of coupled equations to portray the relationships among major atmospheric and oceanic modes, including the NAO, AMO, AMOC, ENSO and stratospheric NAM. The simple model reproduces the strongly timescale-dependent character of the relationships, which changes in strength and direction on scales ranging from days to centuries. Another emphasis is placed on explicitly resolving the air-sea heat fluxes as a function of timescale to provide insight into the coupling between ocean and atmosphere. In constructing and testing the simple model we make use of a multi-millennium-long control integration with a fully coupled climate model. Cross-correlation, spectral analysis and inverse methods are employed to characterize important aspects of the interactions in the full and simple models. It is found that, a) Bjerknes' conjecture on ocean-atmosphere coupling, that is the atmosphere drives climate on high frequencies (days to months) while the ocean acts as the main source of climate variability on interannual and longer timescales, is confirmed; b) the AMOC can be readily understood as a harmonic oscillator driven by the NAO; c) the two-way interaction between NAO and AMO, and also the influence of ENSO on both NAO and AMO are essential for reproducing important correlation features; and d) the consideration of heat fluxes provides additional explanatory power to our model. Our approach not only helps to clarify our understanding for the nature of the atmosphere-ocean interaction problem but also raises new and intriguing questions for future research.

  7. A conceptual model for milling formations in biological aggregates.

    PubMed

    Lukeman, Ryan; Li, Yue-Xian; Edelstein-Keshet, Leah

    2009-02-01

    Collective behavior of swarms and flocks has been studied from several perspectives, including continuous (Eulerian) and individual-based (Lagrangian) models. Here, we use the latter approach to examine a minimal model for the formation and maintenance of group structure, with specific emphasis on a simple milling pattern in which particles follow one another around a closed circular path.We explore how rules and interactions at the level of the individuals lead to this pattern at the level of the group. In contrast to many studies based on simulation results, our model is sufficiently simple that we can obtain analytical predictions. We consider a Newtonian framework with distance-dependent pairwise interaction-force. Unlike some other studies, our mill formations do not depend on domain boundaries, nor on centrally attracting force-fields or rotor chemotaxis.By focusing on a simple geometry and simple distant-dependent interactions, we characterize mill formations and derive existence conditions in terms of model parameters. An eigenvalue equation specifies stability regions based on properties of the interaction function. We explore this equation numerically, and validate the stability conclusions via simulation, showing distinct behavior inside, outside, and on the boundary of stability regions. Moving mill formations are then investigated, showing the effect of individual autonomous self-propulsion on group-level motion. The simplified framework allows us to clearly relate individual properties (via model parameters) to group-level structure. These relationships provide insight into the more complicated milling formations observed in nature, and suggest design properties of artificial schools where such rotational motion is desired. PMID:18855072

  8. Integrating O/S models during conceptual design, part 3

    NASA Astrophysics Data System (ADS)

    Ebeling, Charles E.

    1994-12-01

    Space vehicles, such as the Space Shuttle, require intensive ground support prior to, during, and after each mission. Maintenance is a significant part of that ground support. All space vehicles require scheduled maintenance to ensure operability and performance. In addition, components of any vehicle are not one-hundred percent reliable so they exhibit random failures. Once detected, a failure initiates unscheduled maintenance on the vehicle. Maintenance decreases the number of missions which can be completed by keeping vehicles out of service so that the time between the completion of one mission and the start of the next is increased. Maintenance also requires resources such as people, facilities, tooling, and spare parts. Assessing the mission capability and resource requirements of any new space vehicle, in addition to performance specification, is necessary to predict the life cycle cost and success of the vehicle. Maintenance and logistics support has been modeled by computer simulation to estimate mission capability and resource requirements for evaluation of proposed space vehicles. The simulation was written with Simulation Language for Alternative Modeling II (SLAM II) for execution on a personal computer. For either one or a fleet of space vehicles, the model simulates the preflight maintenance checks, the mission and return to earth, and the post flight maintenance in preparation to be sent back into space. THe model enables prediction of the number of missions possible and vehicle turn-time (the time between completion of one mission and the start of the next) given estimated values for component reliability and maintainability. The model also facilitates study of the manpower and vehicle requirements for the proposed vehicle to meet its desired mission rate. This is the 3rd part of a 3 part technical report.

  9. Conceptual models used by nurses working in coronary care units--a discussion paper.

    PubMed

    Timmins, Fiona

    2006-12-01

    In the UK, Europe and the USA conceptual models of nursing are features of many undergraduate nursing curricula [Alligood MR. The nature of knowledge needed for nursing practice. In Alligood MR, Marriner-Tomey A, editors. Nursing theory utilisation and application. London: Mosby, 2002, Tierney AJ. Nursing models extant or extinct? J Adv Nurs 1998;8(1):77-85] and commonly used in practice. However, UK nurses in practice continue to be dissatisfied with conceptual model use [Griffiths P. An investigation into the description of patients' problems by nurses using two different needs-based nursing models. J Adv Nurs 1998;28(5):969-977, Mason C. Guide to practice or 'load of rubbish'? The influence of care plans on nursing practice in five clinical areas in Northern Ireland. J Adv Nurs 1999;29(2):380-387, Murphy K, Cooney A, Casey D, Connor M, O'Connor J., Dineen B. The Roper, Logan and Tierney Model: perceptions and operationalization of the model in psychiatric nursing within one health board in Ireland. J Adv Nurs 2000;31(6):1333-1341]. An association with increased paperwork and documentation together with a belief that these abstract concepts do not quite fit with the practice setting has resulted in a generalised apathy towards their use in some areas [Timmins F. Critical care nursing in the 21st Century. Intensive Crit Care Nurs 2002;18:118-127]. In an era of concerns about both cost and quality, together with an increased impetus towards multi-professional working patterns and role expansion, alternative models of care, such as critical pathways and care pathways are gaining increased favour in the clinical setting [Johnson S, editor. Pathways of care. Oxford; Blackwell Science 1997]. The aim of this paper is to consider whether or not the traditional conceptual models of nursing are apt for today's practicing coronary care nurse. Specific questions to be addressed are: what is the research evidence that informs conceptual model use in coronary care and what are

  10. Conceptual model of turbulent flameholding for scramjet combustors

    NASA Technical Reports Server (NTRS)

    Huber, P. W.

    1980-01-01

    New concepts and approaches to scramjet combustor design are presented. Blowoff was from failure of the recirculation-zone (RZ) flame to reach the dividing streamline (DS) at the rear stagnation zone. Increased turbulent exchange across the DS helped flameholding due to forward movement of the flame anchor point inside the RZ. Modeling of the blowoff phenomenon was based on a mass conservation concept involving the traverse of a flame element across the RZ and a flow element along the DS. The scale required to achieve flameholding, predicted by the model, showed a strong adverse effect of low pressure and low fuel equivalence ratio, moderate effect of flight Mach number, and little effect of temperature recovery factor. Possible effects of finite rate chemistry on flameholding and flamespreading in scramjets are discussed and recommendations for approaches to engine combustor design as well as for needed research to reduce uncertainties in the concepts are made.

  11. Evidence-based ergonomics: a model and conceptual structure proposal.

    PubMed

    Silveira, Dierci Marcio

    2012-01-01

    In Human Factors and Ergonomics Science (HFES), it is difficult to identify what is the best approach to tackle the workplace and systems design problems which needs to be solved, and it has been also advocated as transdisciplinary and multidisciplinary the issue of "How to solve the human factors and ergonomics problems that are identified?". The proposition on this study is to combine the theoretical approach for Sustainability Science, the Taxonomy of the Human Factors and Ergonomics (HFE) discipline and the framework for Evidence-Based Medicine in an attempt to be applied in Human Factors and Ergonomics. Applications of ontologies are known in the field of medical research and computer science. By scrutinizing the key requirements for the HFES structuring of knowledge, it was designed a reference model, First, it was identified the important requirements for HFES Concept structuring, as regarded by Meister. Second, it was developed an evidence-based ergonomics framework as a reference model composed of six levels based on these requirements. Third, it was devised a mapping tool using linguistic resources to translate human work, systems environment and the complexities inherent to their hierarchical relationships to support future development at Level 2 of the reference model and for meeting the two major challenges for HFES, namely, identifying what problems should be addressed in HFE as an Autonomous Science itself and proposing solutions by integrating concepts and methods applied in HFES for those problems.

  12. Data Relationships: Towards a Conceptual Model of Scientific Data Catalogs

    NASA Astrophysics Data System (ADS)

    Hourcle, J. A.

    2008-12-01

    As the amount of data, types of processing and storage formats increase, the total number of record permutations increase dramatically. The result is an overwhelming number of records that make identifying the best data object to answer a user's needs more difficult. The issue is further complicated as each archive's data catalog may be designed around different concepts - - anything from individual files to be served, series of similarly generated and processed data, or something entirely different. Catalogs may not only be flat tables, but may be structured as multiple tables with each table being a different data series, or a normalized structure of the individual data files. Merging federated search results from archives with different catalog designs can create situations where the data object of interest is difficult to find due to an overwhelming number of seemingly similar or entirely unwanted records. We present a reference model for discussing data catalogs and the complex relationships between similar data objects. We show how the model can be used to improve scientist's ability to quickly identify the best data object for their purposes and discuss technical issues required to use this model in a federated system.

  13. A conceptual model of Verbal Exchange Health Literacy

    PubMed Central

    Harrington, Kathleen F.; Valerio, Melissa A.

    2014-01-01

    Objective To address a gap in understanding of verbal exchange (oral and aural) health literacy by describing the systematic development of a verbal exchange health literacy (VEHL) definition and model which hypothesizes the role of VEHL in health outcomes. Methods Current health literacy and communication literature was systematically reviewed and combined with qualitative patient and provider data that were analyzed using a grounded theory approach. Results Analyses of current literature and formative data indicated the importance of verbal exchange in the clinical setting and revealed various factors associated with the patient-provider relationship and their characteristics that influence decision making and health behaviors. VEHL is defined as the ability to speak and listen that facilitates exchanging, understanding, and interpreting of health information for health-decision making, disease management and navigation of the healthcare system. A model depiction of mediating and influenced factors is presented. Conclusion A definition and model of VEHL is a step towards addressing a gap in health literacy knowledge and provides a foundation for examining the influence of VEHL on health outcomes. Practice Implications VEHL is an extension of current descriptions of health literacy and has implications for patient-provider communication and health decision making. PMID:24291145

  14. [Case study on health risk assessment based on site-specific conceptual model].

    PubMed

    Zhong, Mao-Sheng; Jiang, Lin; Yao, Jue-Jun; Xia, Tian-Xiang; Zhu, Xiao-Ying; Han, Dan; Zhang, Li-Na

    2013-02-01

    Site investigation was carried out on an area to be redeveloped as a subway station, which is right downstream of the groundwater of a former chemical plant. The results indicate the subsurface soil and groundwater in the area are both polluted heavily by 1,2-dichloroethane, which was caused by the chemical plant upstream with the highest concentration was 104.08 mg.kg-1 for soil sample at 8.6 m below ground and the highest concentration was 18500 microg.L-1 for groundwater. Further, a site-specific contamination conceptual model, giving consideration to the specific structure configuration of the station, was developed, and the corresponding risk calculation equation was derived. The carcinogenic risks calculated with models developed on the generic site conceptual model and derived herein on the site-specific conceptual model were compared. Both models indicate that the carcinogenic risk is significantly higher than the acceptable level which is 1 x 10(-6). The comparison result reveals that the risk calculated with the former models for soil and groundwater are higher than the one calculated with the latter models by 2 times and 1.5 times, respectively. The finding in this paper indicates that the generic risk assessment model may underestimate the risk if specific site conditions and structure configuration are not considered.

  15. Advanced Turbine Systems Program, Conceptual Design and Product Development. Task 6, System definition and analysis

    SciTech Connect

    1995-04-01

    The strategy of the ATS program is to develop a new baseline for industrial gas turbine systems for the 21st century, meeting the buying criteria of industrial gas turbine end users, and having growth potential. These criteria guided the Solar ATS Team in selecting the system definition described in this Topical Report. The key to selecting the ATS system definition was meeting or exceeding each technical goal without negatively impacting other commercial goals. Among the most crucial goals are the buying criteria of the industrial gas turbine market. Solar started by preliminarily considering several cycles with the potential to meet ATS program goals. These candidates were initially narrowed based on a qualitative assessment of several factors such as the potential for meeting program goals and for future growth; the probability of successful demonstration within the program`s schedule and expected level of funding; and the appropriateness of the cycle in light of end users` buying criteria. A first level Quality Function Deployment (QFD) analysis then translated customer needs into functional requirements, and ensured favorable interaction between concept features. Based on this analysis, Solar selected a recuperated cycle as the best approach to fulfilling both D.O.E. and Solar marketing goals. This report details the design and analysis of the selected engine concept, and explains how advanced features of system components achieve program goals. Estimates of cost, performance, emissions and RAMD (reliability, availability, maintainability, durability) are also documented in this report.

  16. A Conceptual Model of Assessing Teaching Performance and Intellectual Development of Teacher Candidates: A Pilot Study in the US

    ERIC Educational Resources Information Center

    Song, Kim Hyunsook

    2006-01-01

    A conceptual model was developed in an urban undergraduate education institution in the US to assess teaching performance and intellectual development levels of teacher candidates. Danielson's framework of teaching performance and Perry's pattern of intellectual and ethical development were used for developing a conceptual model. A pilot study was…

  17. The Effects of Common Knowledge Construction Model Sequence of Lessons on Science Achievement and Relational Conceptual Change

    ERIC Educational Resources Information Center

    Ebenezer, Jazlin; Chacko, Sheela; Kaya, Osman Nafiz; Koya, Satya Kiran; Ebenezer, Devairakkam Luke

    2010-01-01

    The purpose of this study was to investigate the effects of the Common Knowledge Construction Model (CKCM) lesson sequence, an intervention based both in conceptual change theory and in Phenomenography, a subset of conceptual change theory. A mixed approach was used to investigate whether this model had a significant effect on 7th grade students'…

  18. Recent advances in modeling stellar interiors (u)

    SciTech Connect

    Guzik, Joyce Ann

    2010-01-01

    Advances in stellar interior modeling are being driven by new data from large-scale surveys and high-precision photometric and spectroscopic observations. Here we focus on single stars in normal evolutionary phases; we will not discuss the many advances in modeling star formation, interacting binaries, supernovae, or neutron stars. We review briefly: (1) updates to input physics of stellar models; (2) progress in two and three-dimensional evolution and hydrodynamic models; (3) insights from oscillation data used to infer stellar interior structure and validate model predictions (asteroseismology). We close by highlighting a few outstanding problems, e.g., the driving mechanisms for hybrid {gamma} Dor/{delta} Sct star pulsations, the cause of giant eruptions seen in luminous blue variables such as {eta} Car and P Cyg, and the solar abundance problem.

  19. Employee commitment and motivation: a conceptual analysis and integrative model.

    PubMed

    Myer, John P; Becker, Thomas E; Vandenberghe, Christian

    2004-12-01

    Theorists and researchers interested in employee commitment and motivation have not made optimal use of each other's work. Commitment researchers seldom address the motivational processes through which commitment affects behavior, and motivation researchers have not recognized important distinctions in the forms, foci, and bases of commitment. To encourage greater cross-fertilization, the authors present an integrative framework in which commitment is presented as one of several energizing forces for motivated behavior. E. A. Locke's (1997) model of the work motivation process and J. P. Meyer and L. Herscovitch's (2001) model of workplace commitments serve as the foundation for the development of this new framework. To facilitate the merger, a new concept, goal regulation, is derived from self-determination theory (E. L. Deci & R. M. Ryan, 1985) and regulatory focus theory (E. I. Higgins, 1997). By including goal regulation, it is acknowledged that motivated behavior can be accompanied by different mindsets that have particularly important implications for the explanation and prediction of discretionary work behavior.

  20. Preliminary conceptual model for mineral evolution in Yucca Mountain

    SciTech Connect

    Duffy, C.J.

    1993-12-01

    A model is presented for mineral alteration in Yucca Mountain, Nevada, that suggests that the mineral transformations observed there are primarily controlled by the activity of aqueous silica. The rate of these reactions is related to the rate of evolution of the metastable silica polymorphs opal-CT and cristobalite assuming that a{sub SiO{sub 2(aq)}} is fixed at the equilibrium solubility of the most soluble silica polymorph present. The rate equations accurately predict the present depths of disappearance of opal-CT and cristobalite. The rate equations have also been used to predict the extent of future mineral alteration that may result from emplacement of a high-level nuclear waste repository in Yucca Mountain. Relatively small changes in mineralogy are predicted, but these predictions are based on the assumption that emplacement of a repository would not increase the pH of water in Yucca Mountain nor increase its carbonate content. Such changes may significantly increase mineral alteration. Some of the reactions currently occurring in Yucca Mountain consume H{sup +} and CO{sub 3}{sup 2{minus}}. Combining reaction rate models for these reactions with water chemistry data may make it possible to estimate water flux through the basal vitrophyre of the Topopah Spring Member and to help confirm the direction and rate of flow of groundwater in Yucca Mountain.

  1. Moving the Watershed Ecosystem Approach Beyond the Black Box with Sensor Technologies and New Conceptual Models

    NASA Astrophysics Data System (ADS)

    Bailey, S. W.; McGuire, K. J.; Ross, D. S.

    2015-12-01

    The small watershed ecosystem as a unit of experimental manipulation and analysis has been a hallmark of the Hubbard Brook Experimental Forest for 60 years. Water and nutrient budgets of headwater catchments have been instrumental in advancing our understanding of the response of forested ecosystems to disturbances such as air pollution and land management. A limitation in the practice of this approach is that point-scale measurements are compiled to create catchment scale estimates of fluxes and stores, thus losing process information that could be gained from spatial patterns that depend on position along hydrologic or biogeochemical pathways. Beginning in 2007, high frequency measurements of water table fluctuation, made possible by inexpensive sensor technology, highlighted the previously underappreciated role of groundwater in these steep headwater catchments. Hydropedologic units (HPUs), identified by morphological differences in soil profiles, and reflecting distinct groundwater regimes, were defined and arranged along a generalized toposequence to describe a conceptual model which partitions spatial variation into predictable, repeatable landscape units. Stratification of point scale measurements of soil and water quality elucidates spatial patterns of variation and allows identification of hot spots, or zones of the catchment where certain processes prevail. Specific HPUs are associated with high rates of dissolved organic matter production, nitrification, denitrification and delivery of mineral weathering products to the surface. Moving beyond the small watershed, contrasting spatial patterns in surface water chemistry at the basin scale suggest differing prevalence of various HPUs among headwater catchments. Comparison of water quality patterns with HPU distribution allows identification of catchment properties responsible for regulation of water quality at the point to the catchment to the basin scales.

  2. METC Gasifier Advanced Simulation (MGAS) model

    SciTech Connect

    Syamlal, M.; Bissett, L.A.

    1992-01-01

    Morgantown Energy Technology Center is developing an advanced moving-bed gasifier, which is the centerpiece of the Integrated Gasifier Combined-Cycle (IGCC) system, with the features of good efficiency, low cost, and minimal environmental impact. A mathematical model of the gasifier, the METC-Gasifier Advanced Simulation (MGAS) model, has been developed for the analysis and design of advanced gasifiers and other moving-bed gasifiers. This report contains the technical and the user manuals of the MGAS model. The MGAS model can describe the transient operation of coflow, counterflow, or fixed-bed gasifiers. It is a one-dimensional model and can simulate the addition and withdrawal of gas and solids at multiple locations in the bed, a feature essential for simulating beds with recycle. The model describes the reactor in terms of a gas phase and a solids (coal or char) phase. These phases may exist at different temperatures. The model considers several combustion, gasification, and initial stage reactions. The model consists of a set of mass balances for 14 gas species and three coal (pseudo-) species and energy balances for the gas and the solids phases. The resulting partial differential equations are solved using a finite difference technique.

  3. Three-dimensional conceptual model for the Hanford Site unconfined aquifer system, FY 1993 status report

    SciTech Connect

    Thorne, P.D.; Chamness, M.A.; Spane, F.A. Jr.; Vermeul, V.R.; Webber, W.D.

    1993-12-01

    The ground water underlying parts of the Hanford Site (Figure 1.1) contains radioactive and chemical contaminants at concentrations exceeding regulatory standards (Dresel et al. 1993). The Hanford Site Ground-Water Surveillance Project, operated by Pacific Northwest Laboratory (PNL), is responsible for monitoring the movement of these contaminants to ensure that public health and the environment are protected. To support the monitoring effort, a sitewide three-dimensional ground-water flow model is being developed. This report provides an update on the status of the conceptual model that will form the basis for constructing a numerical three-dimensional flow model for, the site. Thorne and Chamness (1992) provide additional information on the initial development of the three-dimensional conceptual model.

  4. A year 2003 conceptual model for the U.S. telecommunications infrastructure.

    SciTech Connect

    Cox, Roger Gary; Reinert, Rhonda K.

    2003-12-01

    To model the telecommunications infrastructure and its role and robustness to shocks, we must characterize the business and engineering of telecommunications systems in the year 2003 and beyond. By analogy to environmental systems modeling, we seek to develop a 'conceptual model' for telecommunications. Here, the conceptual model is a list of high-level assumptions consistent with the economic and engineering architectures of telecommunications suppliers and customers, both today and in the near future. We describe the present engineering architectures of the most popular service offerings, and describe the supplier markets in some detail. We also develop a characterization of the customer base for telecommunications services and project its likely response to disruptions in service, base-lining such conjectures against observed behaviors during 9/11.

  5. Some problems with social cognition models: a pragmatic and conceptual analysis.

    PubMed

    Ogden, Jane

    2003-07-01

    Empirical articles published between 1997 and 2001 from 4 health psychology journals that tested or applied 1 or more social cognition models (theory of reasoned action, theory of planned behavior, health belief model, and protection motivation theory; N = 47) were scrutinized for their pragmatic and conceptual basis. In terms of their pragmatic basis, these 4 models were useful for guiding research. The analysis of their conceptual basis was less positive. First, these models do not enable the generation of hypotheses because their constructs are unspecific; they therefore cannot be tested. Second, they focus on analytic truths rather than synthetic ones, and the conclusions resulting from their application are often true by definition rather than by observation. Finally, they may create and change both cognitions and behavior rather than describe them.

  6. Periodic orbits for a discontinuous vector field arising from a conceptual model of glacial cycles

    NASA Astrophysics Data System (ADS)

    Walsh, James; Widiasih, Esther; Hahn, Jonathan; McGehee, Richard

    2016-06-01

    Conceptual climate models provide an approach to understanding climate processes through a mathematical analysis of an approximation to reality. Recently, these models have also provided interesting examples of nonsmooth dynamical systems. Here we develop a new conceptual model of glacial cycles consisting of a system of three ordinary differential equations defining a discontinuous vector field. Our model provides a dynamical systems framework for a mechanism previously shown to play a crucial role in glacial cycle patterns, namely, an increased ice sheet ablation rate during deglaciations. We use ad hoc singular perturbation techniques to prove the existence of a large periodic orbit crossing the discontinuity boundary, provided the ice sheet edge moves sufficiently slowly relative to changes in the snow line and temperature. Numerical explorations reveal the periodic orbit exists when the time constant for the ice sheet edge has more moderate values.

  7. Conceptual ecological models to guide integrated landscape monitoring of the Great Basin

    USGS Publications Warehouse

    Miller, D.M.; Finn, S.P.; Woodward, Andrea; Torregrosa, Alicia; Miller, M.E.; Bedford, D.R.; Brasher, A.M.

    2010-01-01

    The Great Basin Integrated Landscape Monitoring Pilot Project was developed in response to the need for a monitoring and predictive capability that addresses changes in broad landscapes and waterscapes. Human communities and needs are nested within landscapes formed by interactions among the hydrosphere, geosphere, and biosphere. Understanding the complex processes that shape landscapes and deriving ways to manage them sustainably while meeting human needs require sophisticated modeling and monitoring. This document summarizes current understanding of ecosystem structure and function for many of the ecosystems within the Great Basin using conceptual models. The conceptual ecosystem models identify key ecological components and processes, identify external drivers, develop a hierarchical set of models that address both site and landscape attributes, inform regional monitoring strategy, and identify critical gaps in our knowledge of ecosystem function. The report also illustrates an approach for temporal and spatial scaling from site-specific models to landscape models and for understanding cumulative effects. Eventually, conceptual models can provide a structure for designing monitoring programs, interpreting monitoring and other data, and assessing the accuracy of our understanding of ecosystem functions and processes.

  8. A conceptual model of Kilauea's magma plumbing system

    NASA Astrophysics Data System (ADS)

    Poland, M. P.; Miklius, A.; Montgomery-Brown, E. K.

    2013-12-01

    The current magma plumbing system of Kilauea Volcano, Hawai`i, is routinely described as consisting of a conduit that extends upward from mantle depths and feeds a magma storage reservoir beneath the summit caldera. From the summit reservoir, rift zones radiate to the east and southwest. Geological and geophysical observations, however, suggest a more complex picture. Models of the summit magma storage area include at least three discrete reservoirs. The largest is centered at ~3 km depth beneath the southern part of the caldera and serves as the main storage volume for the volcano. A smaller body lies 1-2 km beneath the east margin of Halema`uma`u Crater and presumably feeds the summit eruptive vent (active since 2008). Magma is also occasionally stored beneath the southeast part of the caldera near Keanakāko`i Crater, where the east rift zone intersects the summit. The reservoirs are interconnected, but the level of connectivity appears to vary according to pressurization of the magma plumbing system. Kilauea's rift zone system extends both to the east and southwest as paired shallow and deeper sections. The deeper rift zones (~3-km depth) are connected to the south caldera reservoir and, along with the Koa`e fault system, represent the structural boundaries of Kilauea's mobile south flank. Both trend southward near the summit before bending into east/northeast- and southwest-directed orientations, which may reflect southward migration of the rift zones over time due to seaward motion of the volcano's south flank (originally proposed by Swanson et al., 1976). Isolated pods of magma (relict from past intrusions) are scattered along the rift zone trends, and molten cores allow for rapid transport of magma between the summit and distal eruption/intrusion sites portions. The shallow rift zones (~1-km depth) are connected to the summit magma system via the Halema`uma`u reservoir and probably represent the former locations of the main rift systems. While this model is

  9. A model for conceptual processing of naturalistic scenes.

    PubMed

    Hanna, A; Loftus, G

    1993-09-01

    Are there fundamental differences in the way in which a list of pictures and a list of words are processed? We report three experiments that examine serial position effects for rapidly-presented naturalistic scenes. The experiments provide a basis for comparison with the U-shaped serial position curve and list-length effect which typically result from verbal learning experiments. In contrast to the U-shaped verbal serial position function, our results show a flat function at the beginning serial positions and a recency effect which is small and limited to the last serial position. There is a set-size effect. Results suggest that the processing leading to a memory representation for visual stimuli such as pictures and linguistic stimuli such as words is qualitatively dissimilar. The findings can be accounted for by a serial processing model whose main parameter is the probability that the subject will switch attention from one picture to the next.

  10. Advances in scientific balloon thermal modeling

    NASA Astrophysics Data System (ADS)

    Bohaboj, T.; Cathey, H.

    The National Aeronautics and Space Administration's Balloon Program Office has long acknowledged that the accurate modeling of balloon performance and flight prediction is dependant on how well the balloon is thermally modeled. This ongoing effort is focused on developing accurate balloon thermal models that can be used to quickly predict balloon temperatures and balloon performance. The ability to model parametric changes is also a driver for this effort. This paper will present the most recent advances made in this area. This research effort continues to utilize the ``Thermal Desktop'' addition to AUTO CAD for the modeling. Recent advances have been made by using this analytical tool. A number of analyses have been completed to test the applicability of this tool to the problem with very positive results. Progressively detailed models have been developed to explore the capabilities of the tool as well as to provide guidance in model formulation. A number of parametric studies have been completed. These studies have varied the shape of the structure, material properties, environmental inputs, and model geometry. These studies have concentrated on spherical ``proxy models'' for the initial development stages and then to transition to the natural shaped zero pressure and super pressure balloons. An assessment of required model resolution has also been determined. Model solutions have been cross checked with known solutions via hand calculations. The comparison of these cases will also be presented. One goal is to develop analysis guidelines and an approach for modeling balloons for both simple first order estimates and detailed full models. This paper presents the step by step advances made as part of this effort, capabilities, limitations, and the lessons learned. Also presented are the plans for further thermal modeling work.

  11. SITE CHARACTERIZATION TO SUPPORT DEVELOPMENT OF CONCEPTUAL SITE MODELS AND TRANSPORT MODELS FOR MONITORING CONTAMINANTS IN GROUND WATER

    EPA Science Inventory

    The development of conceptual and predictive models is an important tool to guide site characterization in support of monitoring contaminants in ground water. The accuracy of predictive models is limited by the adequacy of the input data and the assumptions made to constrain mod...

  12. Conceptualization of Approaches and Thought Processes Emerging in Validating of Model in Mathematical Modeling in Technology Aided Environment

    ERIC Educational Resources Information Center

    Hidiroglu, Çaglar Naci; Bukova Güzel, Esra

    2013-01-01

    The aim of the present study is to conceptualize the approaches displayed for validation of model and thought processes provided in mathematical modeling process performed in technology-aided learning environment. The participants of this grounded theory study were nineteen secondary school mathematics student teachers. The data gathered from the…

  13. What Can Be Learned From a Laboratory Model of Conceptual Change? Descriptive Findings and Methodological Issues

    NASA Astrophysics Data System (ADS)

    Ohlsson, Stellan; Cosejo, David G.

    2014-07-01

    The problem of how people process novel and unexpected information— deep learning (Ohlsson in Deep learning: how the mind overrides experience. Cambridge University Press, New York, 2011)—is central to several fields of research, including creativity, belief revision, and conceptual change. Researchers have not converged on a single theory for conceptual change, nor has any one theory been decisively falsified. One contributing reason is the difficulty of collecting informative data in this field. We propose that the commonly used methodologies of historical analysis, classroom interventions, and developmental studies, although indispensible, can be supplemented with studies of laboratory models of conceptual change. We introduce re- categorization, an experimental paradigm in which learners transition from one definition of a categorical concept to another, incompatible definition of the same concept, a simple form of conceptual change. We describe a re-categorization experiment, report some descriptive findings pertaining to the effects of category complexity, the temporal unfolding of learning, and the nature of the learner's final knowledge state. We end with a brief discussion of ways in which the re-categorization model can be improved.

  14. Advanced turbine systems program conceptual design and product development. Task 3 -- System selection; Topical report

    SciTech Connect

    White, D.J.

    1994-07-01

    Solar Turbines Incorporated has elected to pursue an intercooled and recuperated (ICR) gas turbine system to exceed the goals of the DOE Advanced Turbine Systems (ATS) program, which are to develop and commercialize an industrial gas turbine system that operates at thermal efficiencies at least 15% higher than 1991 products, and with emissions not exceeding eight ppmv NOx and 20 ppmv CO and UHC. Solar`s goal is to develop a commercially viable industrial system (3--20 MW) driven by a gas turbine engine with a thermal efficiency of 50% (ATS50), with the flexibility to meet the differing operational requirements of various markets. Dispersed power generation is currently considered to be the primary future target market for the ICR in the 5--15 MW size class. The ICR integrated system approach provides an ideal candidate for the assumed dispersed power market, with its small footprint, easy transportability, and environmental friendliness. In comparison with other systems that use water or toxic chemicals such as ammonia for NOx control, the ICR has no consumables other than fuel and air. The low pressure ratio of the gas turbine engine also is favorable in that less parasitic power is needed to pump the natural gas into the combustor than for simple-cycle machines. Solar has narrowed the ICR configuration to two basic approaches, a 1-spool, and a 2-spool version of the ATS50. The 1-spool engine will have a lower first-cost but lower part-power efficiencies. The 2-spool ATS may not only have better part-power efficiency, its efficiency will also be less sensitive to reduced turbine rotor inlet temperature levels. Thus hot-end parts life can be increased with only small sacrifices in efficiency. The flexibility of the 2-spool arrangement in meeting customer needs is its major advantage over the 1-spool. This Task 3 Topical Report is intended to present Solar`s preliminary system selection based upon the initial trade-off studies performed to date.

  15. Advancing a sociotechnical systems approach to workplace safety – developing the conceptual framework

    PubMed Central

    Carayon, Pascale; Hancock, Peter; Leveson, Nancy; Noy, Ian; Sznelwar, Laerte; van Hootegem, Geert

    2015-01-01

    Traditional efforts to deal with the enormous problem of workplace safety have proved insufficient, as they have tended to neglect the broader sociotechnical environment that surrounds workers. Here, we advocate a sociotechnical systems approach that describes the complex multi-level system factors that contribute to workplace safety. From the literature on sociotechnical systems, complex systems and safety, we develop a sociotechnical model of workplace safety with concentric layers of the work system, socio-organisational context and the external environment. The future challenges that are identified through the model are highlighted. Practitioner Summary: Understanding the environmental, organisational and work system factors that contribute to workplace safety will help to develop more effective and integrated solutions to deal with persistent workplace safety problems. Solutions to improve workplace safety need to recognise the broad sociotechnical system and the respective interactions between the system elements and levels. PMID:25831959

  16. Conceptual modeling of coincident failures in multiversion software

    NASA Technical Reports Server (NTRS)

    Littlewood, Bev; Miller, Douglas R.

    1989-01-01

    Recent work by Eckhardt and Lee (1985) shows that independently developed program versions fail dependently (specifically, simultaneous failure of several is greater than would be the case under true independence). The present authors show there is a precise duality between input choice and program choice in this model and consider a generalization in which different versions can be developed using diverse methodologies. The use of diverse methodologies is shown to decrease the probability of the simultaneous failure of several versions. Indeed, it is theoretically possible to obtain versions which exhibit better than independent failure behavior. The authors try to formalize the notion of methodological diversity by considering the sequence of decision outcomes that constitute a methodology. They show that diversity of decision implies likely diversity of behavior for the different verions developed under such forced diversity. For certain one-out-of-n systems the authors obtain an optimal method for allocating diversity between versions. For two-out-of-three systems there seem to be no simple optimality results which do not depend on constraints which cannot be verified in practice.

  17. Center for Advanced Modeling and Simulation Intern

    ScienceCinema

    Gertman, Vanessa

    2016-07-12

    Some interns just copy papers and seal envelopes. Not at INL! Check out how Vanessa Gertman, an INL intern working at the Center for Advanced Modeling and Simulation, spent her summer working with some intense visualization software. Lots more content like this is available at INL's facebook page http://www.facebook.com/idahonationallaboratory.

  18. Center for Advanced Modeling and Simulation Intern

    SciTech Connect

    Gertman, Vanessa

    2010-01-01

    Some interns just copy papers and seal envelopes. Not at INL! Check out how Vanessa Gertman, an INL intern working at the Center for Advanced Modeling and Simulation, spent her summer working with some intense visualization software. Lots more content like this is available at INL's facebook page http://www.facebook.com/idahonationallaboratory.

  19. Comparison of Various Optimization Methods for Calibration of Conceptual Rainfall-Runoff Models

    NASA Astrophysics Data System (ADS)

    Bhatt, Divya; Jain, Ashu

    2010-05-01

    Runoff forecasts are needed in many water resources activities such as flood and drought management, irrigation practices, and water distribution systems, etc. Runoff is generally forecasted using rainfall-runoff models by using hydrologic data in the catchment. Computer based hydrologic models have become popular with practicing hydrologists and water resources engineers for performing hydrologic forecasts and for managing water systems. Rainfall-runoff library (RRL) is computer software developed by Cooperative Research Centre for Catchment Hydrology (CRCCH), Australia. The RRL consists of five different conceptual rainfall-runoff models and has been in operation in many water resources applications in Australia. RRL is designed to simulate catchment runoff by using daily rainfall and evapotranspiration data. In this paper, the results from an investigation on the use of different optimization methods for the calibration of various conceptual rainfall-runoff models available in RRL toolkit are presented. Out of the five conceptual models in the RRL toolkit, AWBM (The Australian Water Balance Model) has been employed. Seven different optimization methods are investigated for the calibration of the AWBM model. The optimization methods investigated include uniform random sampling, pattern search, multi start pattern search, Rosenbrock search, Rosenbrock multi-start search, Shuffled Complex Evolution (SCE-UA) and Genetic Algorithm (GA). Trial and error procedures were employed to arrive at the best values of various parameters involved in the optimizers for all to develop the AWBM. The results obtained from the best configuration of the AWBM are presented here for all optimization methods. The daily rainfall and runoff data derived from Bird Creek Basin, Oklahoma, USA have been employed to develop all the models included here. A wide range of error statistics have been used to evaluate the performance of all the models developed in this study. It has been found that

  20. The EBM-DPSER conceptual model: integrating ecosystem services into the DPSIR framework.

    PubMed

    Kelble, Christopher R; Loomis, Dave K; Lovelace, Susan; Nuttle, William K; Ortner, Peter B; Fletcher, Pamela; Cook, Geoffrey S; Lorenz, Jerry J; Boyer, Joseph N

    2013-01-01

    There is a pressing need to integrate biophysical and human dimensions science to better inform holistic ecosystem management supporting the transition from single species or single-sector management to multi-sector ecosystem-based management. Ecosystem-based management should focus upon ecosystem services, since they reflect societal goals, values, desires, and benefits. The inclusion of ecosystem services into holistic management strategies improves management by better capturing the diversity of positive and negative human-natural interactions and making explicit the benefits to society. To facilitate this inclusion, we propose a conceptual model that merges the broadly applied Driver, Pressure, State, Impact, and Response (DPSIR) conceptual model with ecosystem services yielding a Driver, Pressure, State, Ecosystem service, and Response (EBM-DPSER) conceptual model. The impact module in traditional DPSIR models focuses attention upon negative anthropomorphic impacts on the ecosystem; by replacing impacts with ecosystem services the EBM-DPSER model incorporates not only negative, but also positive changes in the ecosystem. Responses occur as a result of changes in ecosystem services and include inter alia management actions directed at proactively altering human population or individual behavior and infrastructure to meet societal goals. The EBM-DPSER conceptual model was applied to the Florida Keys and Dry Tortugas marine ecosystem as a case study to illustrate how it can inform management decisions. This case study captures our system-level understanding and results in a more holistic representation of ecosystem and human society interactions, thus improving our ability to identify trade-offs. The EBM-DPSER model should be a useful operational tool for implementing EBM, in that it fully integrates our knowledge of all ecosystem components while focusing management attention upon those aspects of the ecosystem most important to human society and does so within

  1. The EBM-DPSER conceptual model: integrating ecosystem services into the DPSIR framework.

    PubMed

    Kelble, Christopher R; Loomis, Dave K; Lovelace, Susan; Nuttle, William K; Ortner, Peter B; Fletcher, Pamela; Cook, Geoffrey S; Lorenz, Jerry J; Boyer, Joseph N

    2013-01-01

    There is a pressing need to integrate biophysical and human dimensions science to better inform holistic ecosystem management supporting the transition from single species or single-sector management to multi-sector ecosystem-based management. Ecosystem-based management should focus upon ecosystem services, since they reflect societal goals, values, desires, and benefits. The inclusion of ecosystem services into holistic management strategies improves management by better capturing the diversity of positive and negative human-natural interactions and making explicit the benefits to society. To facilitate this inclusion, we propose a conceptual model that merges the broadly applied Driver, Pressure, State, Impact, and Response (DPSIR) conceptual model with ecosystem services yielding a Driver, Pressure, State, Ecosystem service, and Response (EBM-DPSER) conceptual model. The impact module in traditional DPSIR models focuses attention upon negative anthropomorphic impacts on the ecosystem; by replacing impacts with ecosystem services the EBM-DPSER model incorporates not only negative, but also positive changes in the ecosystem. Responses occur as a result of changes in ecosystem services and include inter alia management actions directed at proactively altering human population or individual behavior and infrastructure to meet societal goals. The EBM-DPSER conceptual model was applied to the Florida Keys and Dry Tortugas marine ecosystem as a case study to illustrate how it can inform management decisions. This case study captures our system-level understanding and results in a more holistic representation of ecosystem and human society interactions, thus improving our ability to identify trade-offs. The EBM-DPSER model should be a useful operational tool for implementing EBM, in that it fully integrates our knowledge of all ecosystem components while focusing management attention upon those aspects of the ecosystem most important to human society and does so within

  2. The EBM-DPSER Conceptual Model: Integrating Ecosystem Services into the DPSIR Framework

    PubMed Central

    Kelble, Christopher R.; Loomis, Dave K.; Lovelace, Susan; Nuttle, William K.; Ortner, Peter B.; Fletcher, Pamela; Cook, Geoffrey S.; Lorenz, Jerry J.; Boyer, Joseph N.

    2013-01-01

    There is a pressing need to integrate biophysical and human dimensions science to better inform holistic ecosystem management supporting the transition from single species or single-sector management to multi-sector ecosystem-based management. Ecosystem-based management should focus upon ecosystem services, since they reflect societal goals, values, desires, and benefits. The inclusion of ecosystem services into holistic management strategies improves management by better capturing the diversity of positive and negative human-natural interactions and making explicit the benefits to society. To facilitate this inclusion, we propose a conceptual model that merges the broadly applied Driver, Pressure, State, Impact, and Response (DPSIR) conceptual model with ecosystem services yielding a Driver, Pressure, State, Ecosystem service, and Response (EBM-DPSER) conceptual model. The impact module in traditional DPSIR models focuses attention upon negative anthropomorphic impacts on the ecosystem; by replacing impacts with ecosystem services the EBM-DPSER model incorporates not only negative, but also positive changes in the ecosystem. Responses occur as a result of changes in ecosystem services and include inter alia management actions directed at proactively altering human population or individual behavior and infrastructure to meet societal goals. The EBM-DPSER conceptual model was applied to the Florida Keys and Dry Tortugas marine ecosystem as a case study to illustrate how it can inform management decisions. This case study captures our system-level understanding and results in a more holistic representation of ecosystem and human society interactions, thus improving our ability to identify trade-offs. The EBM-DPSER model should be a useful operational tool for implementing EBM, in that it fully integrates our knowledge of all ecosystem components while focusing management attention upon those aspects of the ecosystem most important to human society and does so within

  3. A conceptual model of ocean freshwater flux derived from sea surface salinity

    NASA Astrophysics Data System (ADS)

    Nieves, V.; Wang, J.; Willis, J. K.

    2014-09-01

    A conceptual model is proposed to express freshwater flux (evaporation minus precipitation) as a function of sea surface salinity (and vice versa). The model is formulated using an idealized one-dimensional diffusion equation for the ocean surface layer. It is shown to provide good agreement with existing freshwater flux estimates and salinity observations. It also has the potential to enhance our capability of monitoring and modeling global freshwater fluxes and salinity as a data retrieval algorithm for remote sensing. The model may improve physical parameterization in coupled ocean-atmosphere models to study the global water cycle.

  4. Conceptual model of iCAL4LA: Proposing the components using comparative analysis

    NASA Astrophysics Data System (ADS)

    Ahmad, Siti Zulaiha; Mutalib, Ariffin Abdul

    2016-08-01

    This paper discusses an on-going study that initiates an initial process in determining the common components for a conceptual model of interactive computer-assisted learning that is specifically designed for low achieving children. This group of children needs a specific learning support that can be used as an alternative learning material in their learning environment. In order to develop the conceptual model, this study extracts the common components from 15 strongly justified computer assisted learning studies. A comparative analysis has been conducted to determine the most appropriate components by using a set of specific indication classification to prioritize the applicability. The results of the extraction process reveal 17 common components for consideration. Later, based on scientific justifications, 16 of them were selected as the proposed components for the model.

  5. The health belief model as a conceptual framework for explaining contraceptive compliance.

    PubMed

    Katatsky, M E

    1977-01-01

    The problem of compliance in family planning is discussed in relation to the lack of theoretical and conceptual clarity in research, which has produced contradictory, and often inconsistent findings. Current research has contributed little to explaining the phenomenon of compliance and to directing further research. The Health Belief Model, which has been demonstrated to have application in the areas of preventive health behavior and compliance with medical regimens, is offered as a potentially useful conceptual framework for family planning research. The generalization of the Health Belief Model to family planning behavior is seen as an out-growth of the theoretical strength of the Model and the similarities between family planning and other health behavior.

  6. [Application analysis of Nursing Care Systematization according to Horta's Conceptual Model].

    PubMed

    da Cunha, Sandra Maria Botelho; Barros, Alba Lúcia Botura Leite

    2005-01-01

    This study has as purpose to analyse the implementation of the Nursing Care Systematization in a private hospital in medical surgical units. Results evidenced that the Horta's Conceptual Model was present only in part of nursing hystory instrument, that the remaining phases of nursing process were not inter-related and that there was a lack of coherence of the prescribed actions in relation to the patient's health condition. From the results of the study it can be concluded that the model used for Nursing Care Systematization is eclectic, not obeying therefore, only to Horta's conceptual model; the totality of the data had not been collected in some phases of the nursing process; there is no correlation of the phases in the majority of analyzed patient records; diagnostic and planning phases do not comprise the phases of the nursing process as proposed by Horta.

  7. Can Cultural Competency Reduce Racial And Ethnic Health Disparities? A Review And Conceptual Model

    PubMed Central

    Brach, Cindy; Fraserirector, Irene

    2016-01-01

    This article develops a conceptual model of cultural competency’s potential to reduce racial and ethnic health disparities, using the cultural competency and disparities literature to lay the foundation for the model and inform assessments of its validity. The authors identify nine major cultural competency techniques: interpreter services, recruitment and retention policies, training, coordinating with traditional healers, use of community health workers, culturally competent health promotion, including family/community members, immersion into another culture, and administrative and organizational accommodations. The conceptual model shows how these techniques could theoretically improve the ability of health systems and their clinicians to deliver appropriate services to diverse populations, thereby improving outcomes and reducing disparities. The authors conclude that while there is substantial research evidence to suggest that cultural competency should in fact work, health systems have little evidence about which cultural competency techniques are effective and less evidence on when and how to implement them properly. PMID:11092163

  8. Simulating runoff under changing climatic conditions: Revisiting an apparent deficiency of conceptual rainfall-runoff models

    NASA Astrophysics Data System (ADS)

    Fowler, Keirnan J. A.; Peel, Murray C.; Western, Andrew W.; Zhang, Lu; Peterson, Tim J.

    2016-03-01

    Hydrologic models have potential to be useful tools in planning for future climate variability. However, recent literature suggests that the current generation of conceptual rainfall runoff models tend to underestimate the sensitivity of runoff to a given change in rainfall, leading to poor performance when evaluated over multiyear droughts. This research revisited this conclusion, investigating whether the observed poor performance could be due to insufficient model calibration and evaluation techniques. We applied an approach based on Pareto optimality to explore trade-offs between model performance in different climatic conditions. Five conceptual rainfall runoff model structures were tested in 86 catchments in Australia, for a total of 430 Pareto analyses. The Pareto results were then compared with results from a commonly used model calibration and evaluation method, the Differential Split Sample Test. We found that the latter often missed potentially promising parameter sets within a given model structure, giving a false negative impression of the capabilities of the model. This suggests that models may be more capable under changing climatic conditions than previously thought. Of the 282[347] cases of apparent model failure under the split sample test using the lower [higher] of two model performance criteria trialed, 155[120] were false negatives. We discuss potential causes of remaining model failures, including the role of data errors. Although the Pareto approach proved useful, our aim was not to suggest an alternative calibration strategy, but to critically assess existing methods of model calibration and evaluation. We recommend caution when interpreting split sample results.

  9. Combustion modeling in advanced gas turbine systems

    SciTech Connect

    Smoot, L.D.; Hedman, P.O.; Fletcher, T.H.; Brewster, B.S.; Kramer, S.K.

    1995-12-31

    Goal of DOE`s Advanced Turbine Systems program is to develop and commercialize ultra-high efficiency, environmentally superior, cost competitive gas turbine systems for base-load applications in utility, independent power producer, and industrial markets. Primary objective of the program here is to develop a comprehensive combustion model for advanced gas turbine combustion systems using natural gas (coal gasification or biomass fuels). The efforts included code evaluation (PCGC-3), coherent anti-Stokes Raman spectroscopy, laser Doppler anemometry, and laser-induced fluorescence.

  10. Ecohydrologic Response of a Wetland Indicator Species to Climate Change and Streamflow Regulation: A Conceptual Model

    NASA Astrophysics Data System (ADS)

    Ward, E. M.; Gorelick, S.

    2015-12-01

    The Peace-Athabasca Delta ("Delta") in northeastern Alberta, Canada, is a UNESCO World Heritage Site and a Ramsar Wetland of International Importance. Delta ecohydrology is expected to respond rapidly to upstream water demand and climate change, with earlier spring meltwater, decreased springtime peak flow, and a decline in springtime ice-jam flooding. We focus on changes in the population and distribution of muskrat (Ondatra zibethicus), an ecohydrologic indicator species. We present a conceptual model linking hydrology and muskrat ecology. Our conceptual model links seven modules representing (1) upstream water demand, (2) streamflow and snowmelt, (3) floods, (4) the water balance of floodplain lakes, (5) muskrat habitat suitability, (6) wetland vegetation, and (7) muskrat population dynamics predicted using an agent-based model. Our goal is to evaluate the effects of different climate change and upstream water demand scenarios on the abundance and distribution of Delta muskrat, from present-2100. Moving from the current conceptual model to a predictive quantitative model, we will rely on abundant existing data and Traditional Ecological Knowledge of muskrat and hydrology in the Delta.

  11. Understanding hydrological flow paths in conceptual catchment models using uncertainty and sensitivity analysis

    NASA Astrophysics Data System (ADS)

    Mockler, Eva M.; O'Loughlin, Fiachra E.; Bruen, Michael

    2016-05-01

    Increasing pressures on water quality due to intensification of agriculture have raised demands for environmental modeling to accurately simulate the movement of diffuse (nonpoint) nutrients in catchments. As hydrological flows drive the movement and attenuation of nutrients, individual hydrological processes in models should be adequately represented for water quality simulations to be meaningful. In particular, the relative contribution of groundwater and surface runoff to rivers is of interest, as increasing nitrate concentrations are linked to higher groundwater discharges. These requirements for hydrological modeling of groundwater contribution to rivers initiated this assessment of internal flow path partitioning in conceptual hydrological models. In this study, a variance based sensitivity analysis method was used to investigate parameter sensitivities and flow partitioning of three conceptual hydrological models simulating 31 Irish catchments. We compared two established conceptual hydrological models (NAM and SMARG) and a new model (SMART), produced especially for water quality modeling. In addition to the criteria that assess streamflow simulations, a ratio of average groundwater contribution to total streamflow was calculated for all simulations over the 16 year study period. As observations time-series of groundwater contributions to streamflow are not available at catchment scale, the groundwater ratios were evaluated against average annual indices of base flow and deep groundwater flow for each catchment. The exploration of sensitivities of internal flow path partitioning was a specific focus to assist in evaluating model performances. Results highlight that model structure has a strong impact on simulated groundwater flow paths. Sensitivity to the internal pathways in the models are not reflected in the performance criteria results. This demonstrates that simulated groundwater contribution should be constrained by independent data to ensure results

  12. Constraining performance assessment models with tracer test results: a comparison between two conceptual models

    NASA Astrophysics Data System (ADS)

    McKenna, Sean A.; Selroos, Jan-Olof

    Tracer tests are conducted to ascertain solute transport parameters of a single rock feature over a 5-m transport pathway. Two different conceptualizations of double-porosity solute transport provide estimates of the tracer breakthrough curves. One of the conceptualizations (single-rate) employs a single effective diffusion coefficient in a matrix with infinite penetration depth. However, the tracer retention between different flow paths can vary as the ratio of flow-wetted surface to flow rate differs between the path lines. The other conceptualization (multirate) employs a continuous distribution of multiple diffusion rate coefficients in a matrix with variable, yet finite, capacity. Application of these two models with the parameters estimated on the tracer test breakthrough curves produces transport results that differ by orders of magnitude in peak concentration and time to peak concentration at the performance assessment (PA) time and length scales (100,000 years and 1,000 m). These differences are examined by calculating the time limits for the diffusive capacity to act as an infinite medium. These limits are compared across both conceptual models and also against characteristic times for diffusion at both the tracer test and PA scales. Additionally, the differences between the models are examined by re-estimating parameters for the multirate model from the traditional double-porosity model results at the PA scale. Results indicate that for each model the amount of the diffusive capacity that acts as an infinite medium over the specified time scale explains the differences between the model results and that tracer tests alone cannot provide reliable estimates of transport parameters for the PA scale. Results of Monte Carlo runs of the transport models with varying travel times and path lengths show consistent results between models and suggest that the variation in flow-wetted surface to flow rate along path lines is insignificant relative to variability in

  13. Maturity Model for Advancing Smart Grid Interoperability

    SciTech Connect

    Knight, Mark; Widergren, Steven E.; Mater, J.; Montgomery, Austin

    2013-10-28

    Abstract—Interoperability is about the properties of devices and systems to connect and work properly. Advancing interoperability eases integration and maintenance of the resulting interconnection. This leads to faster integration, lower labor and component costs, predictability of projects and the resulting performance, and evolutionary paths for upgrade. When specifications are shared and standardized, competition and novel solutions can bring new value streams to the community of stakeholders involved. Advancing interoperability involves reaching agreement for how things join at their interfaces. The quality of the agreements and the alignment of parties involved in the agreement present challenges that are best met with process improvement techniques. The GridWise® Architecture Council (GWAC) sponsored by the United States Department of Energy is supporting an effort to use concepts from capability maturity models used in the software industry to advance interoperability of smart grid technology. An interoperability maturity model has been drafted and experience is being gained through trials on various types of projects and community efforts. This paper describes the value and objectives of maturity models, the nature of the interoperability maturity model and how it compares with other maturity models, and experiences gained with its use.

  14. Seepage weathering impacts on erosivity of arid stream banks: A new conceptual model

    NASA Astrophysics Data System (ADS)

    Nachshon, Uri

    2016-05-01

    Field observations have indicated the formation of horizontal, pipe shape cavities, along gully and dry stream channel banks in the semi-arid region of the northern Negev Desert, Israel. Piping is a well-known phenomenon in humid regions due to subsurface water flow and seepage weathering. However, in dry environments where rain events are scarce and subsurface water flow is rare, it is proposed here that capillary flow of saline water in the vadose zone leads to similar processes. It is suggested that where saline and shallow ground water persists, capillary flow may result in salt accumulation and precipitation at the top of the capillary fringe, consequently rendering this zone to be more susceptible to erosion. A conceptual model is presented and field observations, laboratory experiments, and a physically-based model are used to prove the feasibility of the proposed conceptual model and to explain why salts accumulate at the top of the capillary fringe, even though evaporation acts all along the vertical stream channel or gully banks. It is suggested that the low evaporative flux, in comparison to the liquid water flux, disables salt accumulation along the profile to the top of the capillary fringe where the liquid water flux is minimal. The presented findings strengthen the conceptual model, but thorough field studies are needed to estimate the impact of the proposed mechanism on erosion processes on a field scale.

  15. Testing a Conceptual Model of Postpartum Depressive Symptoms in the First Year.

    PubMed

    Hassert, Silva; Kurpius, Sharon E Robinson; Tracey, Terence J G

    2015-01-01

    Postpartum depressive symptoms (PPDS) are likely to have a multifactorial etiology. The relationships among identified PPDS risk factors, however, remain inconclusive. A vulnerability-stress conceptualization of PPDS was tested with a sample of 144 U.S. mothers aged 18-46 years, who had given birth in the last 12 months. The Edinburgh Postnatal Depression Scale, Dysfunctional Attitude Scale Form A-17, Parenting Sense of Competence Scale, and Quality of Relationships Inventory were completed. The conceptual model and three alternative models were tested using structural equation modeling. A variation of the conceptual model yielded the best fit, χ(2) (98) = 133.541, p = .0099, Standardized Root Mean Residual (SRMR) = 0.071, Root Mean Square Error of Approximation (RMSEA) = 0.050 (90% CI = 0.026-0.070), Tucker Lewis Index (TLI) = 0.953, Comparative Fix Index (CFI) = 0.961. Dependency and partner conflict were positively related to PPDS, while maternal-efficacy was negatively related to PPDS. Dependency moderated the relationship between maternal-efficacy and PPDS, so that this relationship was stronger for mothers with higher dependency than for those with lower dependency. Dependency, partner conflict, and maternal-efficacy should be considered when building interventions that target the wellbeing of mothers in the first year after birth.

  16. Simulation of shallow groundwater levels: Comparison of a data-driven and a conceptual model

    NASA Astrophysics Data System (ADS)

    Fahle, Marcus; Dietrich, Ottfried; Lischeid, Gunnar

    2015-04-01

    Despite an abundance of models aimed at simulating shallow groundwater levels, application of such models is often hampered by a lack of appropriate input data. Difficulties especially arise with regard to soil data, which are typically hard to obtain and prone to spatial variability, eventually leading to uncertainties in the model results. Modelling approaches relying entirely on easily measured quantities are therefore an alternative to encourage the applicability of models. We present and compare two models for calculating 1-day-ahead predictions of the groundwater level that are only based on measurements of potential evapotranspiration, precipitation and groundwater levels. The first model is a newly developed conceptual model that is parametrized using the White method (which estimates the actual evapotranspiration on basis of diurnal groundwater fluctuations) and a rainfall-response ratio. Inverted versions of the two latter approaches are then used to calculate the predictions of the groundwater level. Furthermore, as a completely data-driven alternative, a simple feed-forward multilayer perceptron neural network was trained based on the same inputs and outputs. Data of 4 growing periods (April to October) from a study site situated in the Spreewald wetland in North-east Germany were taken to set-up the models and compare their performance. In addition, response surfaces that relate model outputs to combinations of different input variables are used to reveal those aspects in which the two approaches coincide and those in which they differ. Finally, it will be evaluated whether the conceptual approach can be enhanced by extracting knowledge of the neural network. This is done by replacing in the conceptual model the default function that relates groundwater recharge and groundwater level, which is assumed to be linear, by the non-linear function extracted from the neural network.

  17. Advancing Material Models for Automotive Forming Simulations

    NASA Astrophysics Data System (ADS)

    Vegter, H.; An, Y.; ten Horn, C. H. L. J.; Atzema, E. H.; Roelofsen, M. E.

    2005-08-01

    Simulations in automotive industry need more advanced material models to achieve highly reliable forming and springback predictions. Conventional material models implemented in the FEM-simulation models are not capable to describe the plastic material behaviour during monotonic strain paths with sufficient accuracy. Recently, ESI and Corus co-operate on the implementation of an advanced material model in the FEM-code PAMSTAMP 2G. This applies to the strain hardening model, the influence of strain rate, and the description of the yield locus in these models. A subsequent challenge is the description of the material after a change of strain path. The use of advanced high strength steels in the automotive industry requires a description of plastic material behaviour of multiphase steels. The simplest variant is dual phase steel consisting of a ferritic and a martensitic phase. Multiphase materials also contain a bainitic phase in addition to the ferritic and martensitic phase. More physical descriptions of strain hardening than simple fitted Ludwik/Nadai curves are necessary. Methods to predict plastic behaviour of single-phase materials use a simple dislocation interaction model based on the formed cells structures only. At Corus, a new method is proposed to predict plastic behaviour of multiphase materials have to take hard phases into account, which deform less easily. The resulting deformation gradients create geometrically necessary dislocations. Additional micro-structural information such as morphology and size of hard phase particles or grains is necessary to derive the strain hardening models for this type of materials. Measurements available from the Numisheet benchmarks allow these models to be validated. At Corus, additional measured values are available from cross-die tests. This laboratory test can attain critical deformations by large variations in blank size and processing conditions. The tests are a powerful tool in optimising forming simulations

  18. A conceptual model to facilitate amphibian conservation in the northern Great Plains

    USGS Publications Warehouse

    Mushnet, David M.; Euliss, Ned H.; Stockwell, Craig A.

    2012-01-01

    As pressures on agricultural landscapes to meet worldwide resource needs increase, amphibian populations face numerous threats including habitat destruction, chemical contaminants, disease outbreaks, wetland sedimentation, and synergistic effects of these perturbations. To facilitate conservation planning, we developed a conceptual model depicting elements critical for amphibian conservation in the northern Great Plains. First, we linked upland, wetland, and landscape features to specific ecological attributes. Ecological attributes included adult survival; reproduction and survival to metamorphosis; and successful dispersal and recolonization. Second, we linked ecosystem drivers, ecosystem stressors, and ecological effects of the region to each ecological attribute. Lastly, we summarized information on these ecological attributes and the drivers, stressors, and effects that work in concert to influence the maintenance of viable and genetically diverse amphibian populations in the northern Great Plains. While our focus was on the northern Great Plains, our conceptual model can be tailored to other geographic regions and taxa.

  19. [Nursing care systematization in rehabilitation unit, in accordance to Horta's conceptual model].

    PubMed

    Neves, Rinaldo de Souza

    2006-01-01

    The utilization of a conceptual model in the Nursing Attendance Systemization allows the development of activities based on theoretical references that can guide the implantation and the implementation of nursing proceedings in hospitals. In this article we examine the option made for the implementation of the Horta's conceptual model in the construction of a nursing attendance system in the Rehabilitation Unit of a public hospital located in the Federal District of Brazil. Through the utilization of these theoretical references it was possible to make available a data collection tool based on the basic human needs. The identification of these needs made possible the construction of the hierarchically disposed pyramid of the neurological patients' modified basic needs. Through this reference paper we intend to elaborate the prescription and nursing evolution based in the concepts and standards of the Horta's nursing process, making possible the inter-relationship of all phases of this attendance methodology.

  20. Mercury Issues and Complexities in Oak Ridge, Tennessee; Redefining the Conceptual Model - 12277

    SciTech Connect

    Peterson, Mark; Southworth, George; Watson, David; Looney, Brian; Eddy-Dilek, Carol; Ketelle, Richard

    2012-07-01

    Releases of mercury from an industrial facility in Oak Ridge, Tennessee in the 1950's and early 1960's resulted in contamination of soil and groundwater within the facility, as well as downstream surface waters. Remediation efforts, which began in the 1980's, have decreased waterborne mercury concentrations near the facility, but elevated levels of mercury remain in the soil, sediment, water, and biota. Widespread distribution of mercury sources and complex mercury transport pathways are some of many challenges at the site. For effective environmental management and closure decision making relative to mercury contamination at the facilities, an up-to-date conceptual model of mercury source areas, processes, likely flow paths, and flux was deemed necessary. Recent facility and reconfiguration efforts, site characterizations, remedial actions, and research are facilitating the collection of new mercury data in Oak Ridge. To develop the current model, a multi-organizational team reviewed existing conceptual models from a variety of sources, consolidated historical data and source information, gathered input from local experts with extensive site knowledge, and used recently collected mercury data from a variety of sampling programs. The developed site conceptual model indicates that the nature and extent of mercury concentration and contaminant flux has significantly changed in the ten years since flux-based conceptual models were used for previous remedial action decisions. A new water treatment system has effectively reduced mercury inputs to the creek and is removing substantially greater quantities of mercury from groundwater than was expected. However, fish concentrations in downstream waters have not responded to decreased water concentrations in the stream. Flux from one large out-fall at the creek's headwaters appears to be a greater percentage of the overall flux leaving the site than previous years, albeit year to year variation in flux is large, and the

  1. Advances in Computationally Modeling Human Oral Bioavailability

    PubMed Central

    Wang, Junmei; Hou, Tingjun

    2015-01-01

    Although significant progress has been made in experimental high throughput screening (HTS) of ADME (absorption, distribution, metabolism, excretion) and pharmacokinetic properties, the ADME and Toxicity (ADME-Tox) in silico modeling is still indispensable in drug discovery as it can guide us to wisely select drug candidates prior to expensive ADME screenings and clinical trials. Compared to other ADME-Tox properties, human oral bioavailability (HOBA) is particularly important but extremely difficult to predict. In this paper, the advances in human oral bioavailability modeling will be reviewed. Moreover, our deep insight on how to construct more accurate and reliable HOBA QSAR and classification models will also discussed. PMID:25582307

  2. Precipitation-centered Conceptual Model for Sub-humid Uplands in Lampasas Cut Plains, TX

    NASA Astrophysics Data System (ADS)

    Potter, S. R.; Tu, M.; Wilcox, B. P.

    2011-12-01

    Conceptual understandings of dominant hydrological processes, system interactions and feedbacks, and external forcings operating within catchments often defy simple definition and explanation, especially catchments encompassing transition zones, degraded landscapes, rapid development, and where climate forcings exhibit large variations across time and space. However, it is precisely those areas for which understanding and knowledge are most needed to innovate sustainable management strategies and counter past management blunders and failed restoration efforts. The cut plain of central Texas is one such area. Complex geographic and climatic factors lead to spatially and temporally variable precipitation having frequent dry periods interrupted by intense high-volume precipitation. Fort Hood, an army post located in the southeast cut plain contains landscapes ranging from highly degraded to nearly pristine with a topography mainly comprised of flat-topped mesas separated by broad u-shaped valleys. To understand the hydrology of the area and responses to wet-dry cycles we analyzed 4-years of streamflow and rainfall from 8 catchments, sized between 1819 and 16,000 ha. Since aquifer recharge/discharge and surface stream-groundwater interactions are unimportant, we hypothesized a simple conceptual model driven by precipitation and radiative forcings and having stormflow, baseflow, ET, and two hypothetical storage components. The key storage component was conceptualized as a buffer that was highly integrated with the ET component and exerted controls on baseflow. Radiative energy controlled flux from the buffer to ET. We used the conceptual model in making a bimonthly hydrologic budget, which included buffer volumes and a deficit-surplus indicator. Through the analysis, we were led to speculate that buffer capacity plays key roles in these landscapes and even relatively minor changes in capacity, due to soil compaction for example, might lead to ecological shifts. The

  3. Integration of the Total Lightning Jump Algorithm into Current Operational Warning Environment Conceptual Models

    NASA Technical Reports Server (NTRS)

    Schultz, Chris; Carey, Larry; Schultz, Elise V.; Stano, Geoffrey; Gatlin, Patrick N.; Kozlowski, Danielle M.; Blakeslee, Rich J.; Goodman, Steve

    2013-01-01

    Key points this analysis will address: 1) What physically is going on in the cloud when there is a jump in lightning? -- Updraft variations, Ice fluxes 2) How do these processes fit in with severe storm conceptual models? 3) What would this information provide an end user? --Relate LJA to radar observations, like changes in reflectivity, MESH, VIL, etc. based multi -Doppler derived physical relationships

  4. The Persuasion Model of conceptual change and its application to misconceptions in evolution

    NASA Astrophysics Data System (ADS)

    Garner, Joanna Kate

    Previous work has attempted to account for the factors involved in conceptual change (e.g. Posner, Strike, Hewson & Gertzog, 1982; Pintrich, Marx & Boyle, 1993). While progress has been made, cognitive restructuring remains to be positioned within a unifying theory of change. Here, a new model of conceptual change is put forward. The Persuasion Model of conceptual change builds on previous frameworks (Posner, Strike, Hewson & Gertzog, 1982; Pintrich, Marx & Boyle, 1993; Vosniadou, 1994) including the psychology of persuasion (Heuristic-Systematic Model, Chaiken, 1980; Elaboration Likelihood Model, Petty & Cacioppo, 1986; Social Judgement Theory, Sherif & Hovland, 1953) and cognitive and motivational theories of learning (Johnson-Laird, 1983; Mayer & Moreno, 1988; Wittrock, 1974b). High quality, elaborative processing of a persuasive message leads to change. Mental models are positioned as the mechanism by which meaning is created, manipulated, inspected and evaluated. These processes result in a continuum of cognitive restructuring. A study of conceptual change in Evolutionary Biology examined the viability of the Persuasion Model. It was predicted that knowledge, beliefs, interest and cognitive style would predict elaborative processing. Processing was hypothesized to influence information comprehensibility, plausibility, fruitfulness and compatibility with prior knowledge. Judgments were hypothesized to influence learning outcomes. Evolutionary knowledge and beliefs were assessed at pre- and posttest in 375 college students using multiple choice, likert-scale and extended response items. Need for Cognition, Need for Cognitive Closure, Epistemological Beliefs, Religiosity, Dogmatism, Moral Values and Argument Evaluation Ability were measured using paper-and-pencil questionnaires. Participants read a text and indicated elaborative processing and information evaluation. Ninety percent of participants held at least one misconception at pre-test. Significant gains on

  5. Conceptual ecological models to support detection of ecological change on Alaska National Wildlife Refuges

    USGS Publications Warehouse

    Woodward, Andrea; Beever, Erik A.

    2011-01-01

    More than 31 million hectares of land are protected and managed in 16 refuges by the U.S. Fish and Wildlife Service (USFWS) in Alaska. The vastness and isolation of Alaskan refuges give rise to relatively intact and complete ecosystems. The potential for these lands to provide habitat for trust species is likely to be altered, however, due to global climate change, which is having dramatic effects at high latitudes. The ability of USFWS to effectively manage these lands in the future will be enhanced by a regional inventory and monitoring program that integrates and supplements monitoring currently being implemented by individual refuges. Conceptual models inform monitoring programs in a number of ways, including summarizing important ecosystem components and processes as well as facilitating communication, discussion and debate about the nature of the system and important management issues. This process can lead to hypotheses regarding future changes, likely results of alternative management actions, identification of monitoring indicators, and ultimately, interpretation of monitoring results. As a first step towards developing a monitoring program, the 16 refuges in Alaska each created a conceptual model of their refuge and the landscape context. Models include prominent ecosystem components, drivers, and processes by which components are linked or altered. The Alaska refuge system also recognizes that designing and implementing monitoring at regional and ecoregional extents has numerous scientific, fiscal, logistical, and political advantages over monitoring conducted exclusively at refuge-specific scales. Broad-scale monitoring is particularly advantageous for examining phenomena such as climate change because effects are best interpreted at broader spatial extents. To enable an ecoregional perspective, a rationale was developed for deriving ecoregional boundaries for four ecoregions (Polar, Interior Alaska, Bering Coast, and North Pacific Coast) from the

  6. A Systematic Approach for Developing Conceptual Models of Contaminant Transport at the Hanford Site

    NASA Astrophysics Data System (ADS)

    Murray, C. J.; Last, G. V.; Rohay, V. J.; Schelling, F. J.; Hildebrand, R. D.; Morse, J. G.

    2004-12-01

    The U.S. Department of Energy (DOE) faces many decisions regarding future remedial actions and waste disposal at the Hanford Site in southeast Washington State. To support these decisions, DOE recognized the need for a comprehensive and systematic approach to developing and documenting complete, consistent, and defensible conceptual models of contaminant release and migration. After reviewing existing conceptual model development methodologies that might be applicable to environmental assessments at the Hanford Site, DOE initiated efforts to adapt and implement the Features, Events, and Processes (FEP) methodology developed for use in performance assessments of nuclear waste disposal systems by NIREX. In adapting this methodology for use in the environmental assessments at Hanford, the international list of FEPs, compiled from nuclear waste disposal programs, was evaluated to develop a list of potentially relevant Hanford-specific FEPs. The international nuclear waste programs focus on deep geologic disposal while waste disposal at the Hanford Site involves burial in shallow unconsolidated geologic deposits. Thus, a graphical tool called the Process Relationship Diagram (PRD) was created to assist in identifying the international FEPs and additional factors that are relevant to Hanford, and to illustrate the relationships among these factors. The PRD is similar in form and function to the Master Directed Diagram used by NIREX to provide a visual and systematic structure for the FEP methodology. Adaptation of this approach is showing promise in facilitating the development of conceptual models and selection of relevant factors to be incorporated into environmental uncertainty assessments for the Hanford Site.

  7. The SEM Risk Behavior (SRB) Model: A New Conceptual Model of how Pornography Influences the Sexual Intentions and HIV Risk Behavior of MSM.

    PubMed

    Wilkerson, J Michael; Iantaffi, Alex; Smolenski, Derek J; Brady, Sonya S; Horvath, Keith J; Grey, Jeremy A; Rosser, B R Simon

    2012-01-01

    While the effects of sexually explicit media (SEM) on heterosexuals' sexual intentions and behaviors have been studied, little is known about the consumption and possible influence of SEM among men who have sex with men (MSM). Importantly, conceptual models of how Internet-based SEM influences behavior are lacking. Seventy-nine MSM participated in online focus groups about their SEM viewing preferences and sexual behavior. Twenty-three participants reported recent exposure to a new behavior via SEM. Whether participants modified their sexual intentions and/or engaged in the new behavior depended on three factors: arousal when imagining the behavior, pleasure when attempting the behavior, and trust between sex partners. Based on MSM's experience, we advance a model of how viewing a new sexual behavior in SEM influences sexual intentions and behaviors. The model includes five paths. Three paths result in the maintenance of sexual intentions and behaviors. One path results in a modification of sexual intentions while maintaining previous sexual behaviors, and one path results in a modification of both sexual intentions and behaviors. With this model, researchers have a framework to test associations between SEM consumption and sexual intentions and behavior, and public health programs have a framework to conceptualize SEM-based HIV/STI prevention programs. PMID:23185126

  8. The SEM Risk Behavior (SRB) Model: A New Conceptual Model of how Pornography Influences the Sexual Intentions and HIV Risk Behavior of MSM

    PubMed Central

    Wilkerson, J. Michael; Iantaffi, Alex; Smolenski, Derek J.; Brady, Sonya S.; Horvath, Keith J.; Grey, Jeremy A.; Rosser, B. R. Simon

    2012-01-01

    While the effects of sexually explicit media (SEM) on heterosexuals’ sexual intentions and behaviors have been studied, little is known about the consumption and possible influence of SEM among men who have sex with men (MSM). Importantly, conceptual models of how Internet-based SEM influences behavior are lacking. Seventy-nine MSM participated in online focus groups about their SEM viewing preferences and sexual behavior. Twenty-three participants reported recent exposure to a new behavior via SEM. Whether participants modified their sexual intentions and/or engaged in the new behavior depended on three factors: arousal when imagining the behavior, pleasure when attempting the behavior, and trust between sex partners. Based on MSM’s experience, we advance a model of how viewing a new sexual behavior in SEM influences sexual intentions and behaviors. The model includes five paths. Three paths result in the maintenance of sexual intentions and behaviors. One path results in a modification of sexual intentions while maintaining previous sexual behaviors, and one path results in a modification of both sexual intentions and behaviors. With this model, researchers have a framework to test associations between SEM consumption and sexual intentions and behavior, and public health programs have a framework to conceptualize SEM-based HIV/STI prevention programs. PMID:23185126

  9. The SEM Risk Behavior (SRB) Model: A New Conceptual Model of how Pornography Influences the Sexual Intentions and HIV Risk Behavior of MSM.

    PubMed

    Wilkerson, J Michael; Iantaffi, Alex; Smolenski, Derek J; Brady, Sonya S; Horvath, Keith J; Grey, Jeremy A; Rosser, B R Simon

    2012-01-01

    While the effects of sexually explicit media (SEM) on heterosexuals' sexual intentions and behaviors have been studied, little is known about the consumption and possible influence of SEM among men who have sex with men (MSM). Importantly, conceptual models of how Internet-based SEM influences behavior are lacking. Seventy-nine MSM participated in online focus groups about their SEM viewing preferences and sexual behavior. Twenty-three participants reported recent exposure to a new behavior via SEM. Whether participants modified their sexual intentions and/or engaged in the new behavior depended on three factors: arousal when imagining the behavior, pleasure when attempting the behavior, and trust between sex partners. Based on MSM's experience, we advance a model of how viewing a new sexual behavior in SEM influences sexual intentions and behaviors. The model includes five paths. Three paths result in the maintenance of sexual intentions and behaviors. One path results in a modification of sexual intentions while maintaining previous sexual behaviors, and one path results in a modification of both sexual intentions and behaviors. With this model, researchers have a framework to test associations between SEM consumption and sexual intentions and behavior, and public health programs have a framework to conceptualize SEM-based HIV/STI prevention programs.

  10. Advanced Technology System Scheduling Governance Model

    SciTech Connect

    Ang, Jim; Carnes, Brian; Hoang, Thuc; Vigil, Manuel

    2015-06-11

    In the fall of 2005, the Advanced Simulation and Computing (ASC) Program appointed a team to formulate a governance model for allocating resources and scheduling the stockpile stewardship workload on ASC capability systems. This update to the original document takes into account the new technical challenges and roles for advanced technology (AT) systems and the new ASC Program workload categories that must be supported. The goal of this updated model is to effectively allocate and schedule AT computing resources among all three National Nuclear Security Administration (NNSA) laboratories for weapons deliverables that merit priority on this class of resource. The process outlined below describes how proposed work can be evaluated and approved for resource allocations while preserving high effective utilization of the systems. This approach will provide the broadest possible benefit to the Stockpile Stewardship Program (SSP).

  11. Combustion modeling in advanced gas turbine systems

    SciTech Connect

    Smoot, L.D.; Hedman, P.O.; Fletcher, T.H.

    1995-10-01

    The goal of the U.S. Department of Energy`s Advanced Turbine Systems (ATS) program is to help develop and commercialize ultra-high efficiency, environmentally superior, and cost competitive gas turbine systems for base-load applications in the utility, independent power producer, and industrial markets. Combustion modeling, including emission characteristics, has been identified as a needed, high-priority technology by key professionals in the gas turbine industry.

  12. Cultural competence: a literature review and conceptual model for mental health services.

    PubMed

    Hernandez, Mario; Nesman, Teresa; Mowery, Debra; Acevedo-Polakovich, Ignacio D; Callejas, Linda M

    2009-08-01

    This article presents a conceptual model of organizational cultural competence for use in mental health services that resulted from a comprehensive review of the research literature. The model identifies four factors associated with cultural competence in mental health services (community context, cultural characteristics of local populations, organizational infrastructure, and direct service support) and redefines cultural competence as the degree of compatibility among these factors. A strength of this model of organizational cultural competence is that it facilitates future research and practice in psychiatric services settings and links culturally competent practices to service parity.

  13. Conceptual Advances in Paleontology.

    ERIC Educational Resources Information Center

    Tiffney, Bruce Haynes

    1988-01-01

    Suggests ways to overcome the perception by some people that plants are less understood and interesting than invertebrates or vertebrates. Describes the specialization of reproductive systems and the development of plant-animal interactions to help raise the awareness level of the fossil record of plants. (RT)

  14. Advanced Reach Tool (ART): development of the mechanistic model.

    PubMed

    Fransman, Wouter; Van Tongeren, Martie; Cherrie, John W; Tischer, Martin; Schneider, Thomas; Schinkel, Jody; Kromhout, Hans; Warren, Nick; Goede, Henk; Tielemans, Erik

    2011-11-01

    This paper describes the development of the mechanistic model within a collaborative project, referred to as the Advanced REACH Tool (ART) project, to develop a tool to model inhalation exposure for workers sharing similar operational conditions across different industries and locations in Europe. The ART mechanistic model is based on a conceptual framework that adopts a source receptor approach, which describes the transport of a contaminant from the source to the receptor and defines seven independent principal modifying factors: substance emission potential, activity emission potential, localized controls, segregation, personal enclosure, surface contamination, and dispersion. ART currently differentiates between three different exposure types: vapours, mists, and dust (fumes, fibres, and gases are presently excluded). Various sources were used to assign numerical values to the multipliers to each modifying factor. The evidence used to underpin this assessment procedure was based on chemical and physical laws. In addition, empirical data obtained from literature were used. Where this was not possible, expert elicitation was applied for the assessment procedure. Multipliers for all modifying factors were peer reviewed by leading experts from industry, research institutes, and public authorities across the globe. In addition, several workshops with experts were organized to discuss the proposed exposure multipliers. The mechanistic model is a central part of the ART tool and with advancing knowledge on exposure, determinants will require updates and refinements on a continuous basis, such as the effect of worker behaviour on personal exposure, 'best practice' values that describe the maximum achievable effectiveness of control measures, the intrinsic emission potential of various solid objects (e.g. metal, glass, plastics, etc.), and extending the applicability domain to certain types of exposures (e.g. gas, fume, and fibre exposure).

  15. White paper: landscape on technical and conceptual requirements and competence framework in drug/disease modeling and simulation.

    PubMed

    Vlasakakis, G; Comets, E; Keunecke, A; Gueorguieva, I; Magni, P; Terranova, N; Della Pasqua, O; de Lange, E C; Kloft, C

    2013-01-01

    Pharmaceutical sciences experts and regulators acknowledge that pharmaceutical development as well as drug usage requires more than scientific advancements to cope with current attrition rates/therapeutic failures. Drug disease modeling and simulation (DDM&S) creates a paradigm to enable an integrated and higher-level understanding of drugs, (diseased)systems, and their interactions (systems pharmacology) through mathematical/statistical models (pharmacometrics)(1)-hence facilitating decision making during drug development and therapeutic usage of medicines. To identify gaps and challenges in DDM&S, an inventory of skills and competencies currently available in academia, industry, and clinical practice was obtained through survey. The survey outcomes revealed benefits, weaknesses, and hurdles for the implementation of DDM&S. In addition, the survey indicated that no consensus exists about the knowledge, skills, and attributes required to perform DDM&S activities effectively. Hence, a landscape of technical and conceptual requirements for DDM&S was identified and serves as a basis for developing a framework of competencies to guide future education and training in DDM&S.CPT: Pharmacometrics & Systems Pharmacology (2013) 2, e40; doi:10.1038/psp.2013.16; advance online publication 1 May 2013. PMID:23887723

  16. Advanced Atmospheric Modeling for Emergency Response.

    NASA Astrophysics Data System (ADS)

    Fast, Jerome D.; O'Steen, B. Lance; Addis, Robert P.

    1995-03-01

    Atmospheric transport and diffusion models are an important part of emergency response systems for industrial facilities that have the potential to release significant quantities of toxic or radioactive material into the atmosphere. An advanced atmospheric transport and diffusion modeling system for emergency response and environmental applications, based upon a three-dimensional mesoscale model, has been developed for the U.S. Department of Energy's Savannah River Site so that complex, time-dependent flow fields not explicitly measured can be routinely simulated. To overcome some of the current computational demands of mesoscale models, two operational procedures for the advanced atmospheric transport and diffusion modeling system are described including 1) a semiprognostic calculation to produce high-resolution wind fields for local pollutant transport in the vicinity of the Savannah River Site and 2) a fully prognostic calculation to produce a regional wind field encompassing the southeastern United States for larger-scale pollutant problems. Local and regional observations and large-scale model output are used by the mesoscale model for the initial conditions, lateral boundary conditions, and four-dimensional data assimilation procedure. This paper describes the current status of the modeling system and presents two case studies demonstrating the capabilities of both modes of operation. While the results from the case studies shown in this paper are preliminary and certainly not definitive, they do suggest that the mesoscale model has the potential for improving the prognostic capabilities of atmospheric modeling for emergency response at the Savannah River Site. Long-term model evaluation will be required to determine under what conditions significant forecast errors exist.

  17. Unitary Transformations in the Quantum Model for Conceptual Conjunctions and Its Application to Data Representation.

    PubMed

    Veloz, Tomas; Desjardins, Sylvie

    2015-01-01

    Quantum models of concept combinations have been successful in representing various experimental situations that cannot be accommodated by traditional models based on classical probability or fuzzy set theory. In many cases, the focus has been on producing a representation that fits experimental results to validate quantum models. However, these representations are not always consistent with the cognitive modeling principles. Moreover, some important issues related to the representation of concepts such as the dimensionality of the realization space, the uniqueness of solutions, and the compatibility of measurements, have been overlooked. In this paper, we provide a dimensional analysis of the realization space for the two-sector Fock space model for conjunction of concepts focusing on the first and second sectors separately. We then introduce various representation of concepts that arise from the use of unitary operators in the realization space. In these concrete representations, a pair of concepts and their combination are modeled by a single conceptual state, and by a collection of exemplar-dependent operators. Therefore, they are consistent with cognitive modeling principles. This framework not only provides a uniform approach to model an entire data set, but, because all measurement operators are expressed in the same basis, allows us to address the question of compatibility of measurements. In particular, we present evidence that it may be possible to predict non-commutative effects from partial measurements of conceptual combinations. PMID:26617556

  18. Unitary Transformations in the Quantum Model for Conceptual Conjunctions and Its Application to Data Representation

    PubMed Central

    Veloz, Tomas; Desjardins, Sylvie

    2015-01-01

    Quantum models of concept combinations have been successful in representing various experimental situations that cannot be accommodated by traditional models based on classical probability or fuzzy set theory. In many cases, the focus has been on producing a representation that fits experimental results to validate quantum models. However, these representations are not always consistent with the cognitive modeling principles. Moreover, some important issues related to the representation of concepts such as the dimensionality of the realization space, the uniqueness of solutions, and the compatibility of measurements, have been overlooked. In this paper, we provide a dimensional analysis of the realization space for the two-sector Fock space model for conjunction of concepts focusing on the first and second sectors separately. We then introduce various representation of concepts that arise from the use of unitary operators in the realization space. In these concrete representations, a pair of concepts and their combination are modeled by a single conceptual state, and by a collection of exemplar-dependent operators. Therefore, they are consistent with cognitive modeling principles. This framework not only provides a uniform approach to model an entire data set, but, because all measurement operators are expressed in the same basis, allows us to address the question of compatibility of measurements. In particular, we present evidence that it may be possible to predict non-commutative effects from partial measurements of conceptual combinations. PMID:26617556

  19. A conceptual model for identifying, preventing, and managing secondary conditions in people with disabilities.

    PubMed

    Rimmer, James H; Chen, Ming-De; Hsieh, Kelly

    2011-12-01

    Secondary conditions are considered a direct consequence of having a disability, and many are presumed to be preventable. Although a few researchers have noted that people with disabilities are exposed to several secondary conditions, including pain, fatigue, depression, and obesity, what is lacking in the literature is a conceptual framework for understanding the antecedents, risk factors, and consequences of secondary conditions. To move the rehabilitation and public health professions toward a more unified approach to understanding and managing secondary conditions as well as distinguishing them from chronic and associated conditions, this article proposes a set of criteria for defining secondary conditions and a conceptual model that considers the potential factors associated with their onset, impact, severity, and management.

  20. Community-Based Participatory Research Conceptual Model: Community Partner Consultation and Face Validity

    PubMed Central

    Belone, Lorenda; Lucero, JE.; Duran, B.; Tafoya, G.; Baker, EA.; Chan, D.; Chang, C.; Greene-Moton, E.; Kelley, M.; Wallerstein, Nina

    2016-01-01

    A national community based participatory research (CBPR) team developed a conceptual/logic model of CBPR partnerships to understand the contribution of partnership processes to improved community capacity and health outcomes. With the model primarily developed through academic literature and expert consensus-building, we sought community input to assess face validity and acceptability. Our research team conducted semi-structured focus groups with six partnerships nation-wide. Participants validated and expanded upon existing model constructs and identified new constructs based on “real-world” praxis, resulting in a revised model. Four cross-cutting constructs were identified: trust development, capacity, mutual learning, and power dynamics. By empirically testing the model, we found community face validity and capacity to adapt the model to diverse contexts. We recommend partnerships use and adapt the CBPR model and its constructs, for collective reflection and evaluation, to enhance their partnering practices and achieve their health and research goals. PMID:25361792

  1. Community-Based Participatory Research Conceptual Model: Community Partner Consultation and Face Validity.

    PubMed

    Belone, Lorenda; Lucero, Julie E; Duran, Bonnie; Tafoya, Greg; Baker, Elizabeth A; Chan, Domin; Chang, Charlotte; Greene-Moton, Ella; Kelley, Michele A; Wallerstein, Nina

    2016-01-01

    A national community-based participatory research (CBPR) team developed a conceptual model of CBPR partnerships to understand the contribution of partnership processes to improved community capacity and health outcomes. With the model primarily developed through academic literature and expert consensus building, we sought community input to assess face validity and acceptability. Our research team conducted semi-structured focus groups with six partnerships nationwide. Participants validated and expanded on existing model constructs and identified new constructs based on "real-world" praxis, resulting in a revised model. Four cross-cutting constructs were identified: trust development, capacity, mutual learning, and power dynamics. By empirically testing the model, we found community face validity and capacity to adapt the model to diverse contexts. We recommend partnerships use and adapt the CBPR model and its constructs, for collective reflection and evaluation, to enhance their partnering practices and achieve their health and research goals. PMID:25361792

  2. Accelerating advances in continental domain hydrologic modeling

    USGS Publications Warehouse

    Archfield, Stacey A.; Clark, Martyn; Arheimer, Berit; Hay, Lauren E.; McMillan, Hilary; Kiang, Julie E.; Seibert, Jan; Hakala, Kirsti; Bock, Andrew R.; Wagener, Thorsten; Farmer, William H.; Andreassian, Vazken; Attinger, Sabine; Viglione, Alberto; Knight, Rodney; Markstrom, Steven; Over, Thomas M.

    2015-01-01

    In the past, hydrologic modeling of surface water resources has mainly focused on simulating the hydrologic cycle at local to regional catchment modeling domains. There now exists a level of maturity among the catchment, global water security, and land surface modeling communities such that these communities are converging toward continental domain hydrologic models. This commentary, written from a catchment hydrology community perspective, provides a review of progress in each community toward this achievement, identifies common challenges the communities face, and details immediate and specific areas in which these communities can mutually benefit one another from the convergence of their research perspectives. Those include: (1) creating new incentives and infrastructure to report and share model inputs, outputs, and parameters in data services and open access, machine-independent formats for model replication or reanalysis; (2) ensuring that hydrologic models have: sufficient complexity to represent the dominant physical processes and adequate representation of anthropogenic impacts on the terrestrial water cycle, a process-based approach to model parameter estimation, and appropriate parameterizations to represent large-scale fluxes and scaling behavior; (3) maintaining a balance between model complexity and data availability as well as uncertainties; and (4) quantifying and communicating significant advancements toward these modeling goals.

  3. Accelerating advances in continental domain hydrologic modeling

    NASA Astrophysics Data System (ADS)

    Archfield, Stacey A.; Clark, Martyn; Arheimer, Berit; Hay, Lauren E.; McMillan, Hilary; Kiang, Julie E.; Seibert, Jan; Hakala, Kirsti; Bock, Andrew; Wagener, Thorsten; Farmer, William H.; Andréassian, Vazken; Attinger, Sabine; Viglione, Alberto; Knight, Rodney; Markstrom, Steven; Over, Thomas

    2015-12-01

    In the past, hydrologic modeling of surface water resources has mainly focused on simulating the hydrologic cycle at local to regional catchment modeling domains. There now exists a level of maturity among the catchment, global water security, and land surface modeling communities such that these communities are converging toward continental domain hydrologic models. This commentary, written from a catchment hydrology community perspective, provides a review of progress in each community toward this achievement, identifies common challenges the communities face, and details immediate and specific areas in which these communities can mutually benefit one another from the convergence of their research perspectives. Those include: (1) creating new incentives and infrastructure to report and share model inputs, outputs, and parameters in data services and open access, machine-independent formats for model replication or reanalysis; (2) ensuring that hydrologic models have: sufficient complexity to represent the dominant physical processes and adequate representation of anthropogenic impacts on the terrestrial water cycle, a process-based approach to model parameter estimation, and appropriate parameterizations to represent large-scale fluxes and scaling behavior; (3) maintaining a balance between model complexity and data availability as well as uncertainties; and (4) quantifying and communicating significant advancements toward these modeling goals.

  4. Toward a Conceptual Framework and Analytical Model of the Process of Organized Technological Innovation Within the Firm.

    ERIC Educational Resources Information Center

    Baker, Norman R.; Sweeney, Dennis J.

    This paper demonstrates that the literature is sufficiently advanced to support the development of conceptual frameworks for organized technological innovation. The literature of multiyear planning and fiscal-year budgeting is examined in order to specify how corporate strategy impinges on organized technological innovation. A computer simulation…

  5. Comparison of a Neural Network and a Conceptual Model for Rainfall-Runoff Modelling with Monthly Input

    NASA Astrophysics Data System (ADS)

    Chochlidakis, Chronis; Daliakopoulos, Ioannis; Tsanis, Ioannis

    2014-05-01

    Rainfall-runoff (RR) models contain parameters that can seldom be directly measured or estimated by expert judgment, but are rather inferred by calibration against a historical record of input-output datasets. Here, a comparison is made between a conceptual model and an Artificial Neural Network (ANN) for efficient modeling of complex hydrological processes. The monthly rainfall, streamflow, and evapotranspiration data from 15 catchments in Crete, Greece are used to compare the proposed methodologies. Genetic Algorithms (GA) are applied for the stochastic calibration of the parameters in the Sacramento Soil Moisture Accounting (SAC-SMA) model yielding R2 values between 0.65 and 0.90. A Feedforward NN (FNN) is trained using a time delay approach, optimized through trial and error for each catchment, yielding R2 values between 0.70 and 0.91. The results obtained show that the ANN models can be superior to the conventional conceptual models due to their ability to handle the non-linearity and dynamic nature of the natural physical processes in a more efficient manner. On the other hand, SAC-SMA depicts high flows with greater accuracy and results suggest that conceptual models can be more robust in extrapolating beyond historical record limits.

  6. Enhancing student teachers' epistemological beliefs about models and conceptual understanding through a model-based inquiry process

    NASA Astrophysics Data System (ADS)

    Soulios, Ioannis; Psillos, Dimitris

    2016-05-01

    In this study we present the structure and implementation of a model-based inquiry teaching-learning sequence (TLS) integrating expressive, experimental and exploratory modelling pedagogies in a cyclic manner, with the aim of enhancing primary education student teachers' epistemological beliefs about the aspects, nature, purpose and change of models as well as their conceptual understanding of light phenomena related to properties of optical fibres. The subjects were 16 prospective primary teachers involved in modelling activities, employing both hands-on experiments and computer modelling activities, based on the application of the ray model. Student teachers were tested before and after the implementation of the TLS by semi-structured interviews and a written questionnaire. Results show that before the TLS most students adopted epistemologically naïve realistic beliefs about models, whereas after the TLS there was an overall significant transition from naïve to more sophisticated epistemological beliefs, as well as significant improvements in their conceptual knowledge about light phenomena. Nevertheless, the relation between epistemological beliefs and conceptual understanding seems to be aspect-dependent, so our evidence suggests that more educational effort is required in order to establish a coherent relationship between them.

  7. [The development of a research program based on a conceptual model for the discipline of nursing].

    PubMed

    Pepin, J; Ducharme, F; Kérouac, S; Lévesque, L; Ricard, N; Duquette, A

    1994-01-01

    The purpose of this article was to illustrate the development of a team's research program based on a conceptual model for the nursing discipline: Roy's Adaptation Model. The ongoing research program includes studies of psychosocial factors, theoretically known for their potential for explaining health. Four groups of people are the focus of these studies: aged spouses in the community, family caregivers of ill elderly people, family caregivers of mentally ill people, and nurses as professional caregivers for elderly people in institutions. The studies are articulated using the three-level structure proposed by Fawcett & Downs (1986) and Fawcett (1991): conceptual-theoretical-empirical. This research program aims to renew understanding of the person's adaptation processes to various environmental stimuli, adaptive responses that influence health, and nursing interventions that promote health (i.e., biopsychosocial integrity). In order to specify the research variables and relations to be studied between these variables in the first phase of the program, each research project is also guided by a middle-range theory compatible with Roy's Adaptation Model. Elaborated within related disciplines, these theories are variations of the Stress and Coping theory of Lazarus & Folkman (1984). The results of these studies will be compared and articulated in a model that integrates the patterns of relations between the variables. The resulting empirical model together with Roy's conceptual model will be used to guide the development of nursing interventions intended to promote adaptive responses and biopsychosocial integrity. The second phase of the research program includes the implementation and evaluation of nursing strategies that promote adaptation among the four groups of people. This research program is a nursing contribution to certain social issues recognized as priorities by the governments of Canada and Québec. This article is an illustration of one of the various

  8. A new conceptual paradigm for the haemodynamics of salt-sensitive hypertension: a mathematical modelling approach

    PubMed Central

    Averina, Viktoria A; Othmer, Hans G; Fink, Gregory D; Osborn, John W

    2012-01-01

    A conceptually novel mathematical model of neurogenic angiotensin II-salt hypertension is developed and analysed. The model consists of a lumped parameter circulatory model with two parallel vascular beds; two distinct control mechanisms for both natriuresis and arterial resistances can be implemented, resulting in four versions of the model. In contrast with the classical Guyton–Coleman model (GC model) of hypertension, in the standard version of our new model natriuresis is assumed to be independent of arterial pressure and instead driven solely by sodium intake; arterial resistances are driven by increased sympathetic nervous system activity in response to the elevated plasma angiotensin II and increased salt intake (AngII-salt). We compare the standard version of our new model against a simplified Guyton–Coleman model in which natriuresis is a function of arterial pressure via the pressure–natriuresis mechanism, and arterial resistances are controlled via the whole-body autoregulation mechanism. We show that the simplified GC model and the new model correctly predict haemodynamic and renal excretory responses to induced changes in angiotensin II and sodium inputs. Importantly, the new model reproduces the pressure–natriuresis relationship – the correlation between arterial pressure and sodium excretion – despite the assumption of pressure-independent natriuresis. These results show that our model provides a conceptually new alternative to Guyton's theory without contradicting observed haemodynamic changes or pressure–natriuresis relationships. Furthermore, the new model supports the view that hypertension need not necessarily have a renal aetiology and that long-term arterial pressure could be determined by sympathetic nervous system activity without involving the renal sympathetic nerves. PMID:22890716

  9. Integrating water quality modeling with ecological risk assessment for nonpoint source pollution control: A conceptual framework

    SciTech Connect

    Chen, Y.D.; McCutcheon, S.C.; Rasmussen, T.C.; Nutter, W.L.; Carsel, R.F.

    1993-01-01

    The historical development of water quality protection goals and strategies in the United States is reviewed. The review leads to the identification and discussion of three components (i.e., management mechanism, environmental investigation approaches, and environmental assessment and criteria) for establishing a management framework for nonpoint source pollution control. Water quality modeling and ecological risk assessment are the two most important and promising approaches to the operation of the proposed management framework. A conceptual framework that shows the general integrative relationships between water quality modeling and ecological risk assessment is presented. (Copyright (c) 1993 IAWQ.)

  10. Colloid Transport in Porous Media: A Continuing Survey of Conceptual Model Developmen

    NASA Astrophysics Data System (ADS)

    Ginn, T. R.; Nelson, K.; Kamai, T.; Massoudieh, A.; Nguyen, T. H.; Le Borgne, T.; Meheust, Y.; Turuban, R.; Benjamin, A.; Palomino, A.

    2014-12-01

    The grand challenge problem of understanding colloid transport and filtration processes in porous media continues to defy fundamental solution, limiting progress of engineering science in in fields ranging from human health to water quality to materials engineering to energy production to microbiology. Focused experimental and modeling studies continue to chip away at our ignorance, in particular as regards colloid interactions with surfaces and colloid motion. In this continuing survey we give an updated overview of some of the currently active research areas with a focus on the exciting new conceptual model development and testing, with reference to pore-to-continuum scale experiments and simulations.

  11. Advanced Small Modular Reactor Economics Model Development

    SciTech Connect

    Harrison, Thomas J.

    2014-10-01

    The US Department of Energy Office of Nuclear Energy’s Advanced Small Modular Reactor (SMR) research and development activities focus on four key areas: Developing assessment methods for evaluating advanced SMR technologies and characteristics; and Developing and testing of materials, fuels and fabrication techniques; and Resolving key regulatory issues identified by US Nuclear Regulatory Commission and industry; and Developing advanced instrumentation and controls and human-machine interfaces. This report focuses on development of assessment methods to evaluate advanced SMR technologies and characteristics. Specifically, this report describes the expansion and application of the economic modeling effort at Oak Ridge National Laboratory. Analysis of the current modeling methods shows that one of the primary concerns for the modeling effort is the handling of uncertainty in cost estimates. Monte Carlo–based methods are commonly used to handle uncertainty, especially when implemented by a stand-alone script within a program such as Python or MATLAB. However, a script-based model requires each potential user to have access to a compiler and an executable capable of handling the script. Making the model accessible to multiple independent analysts is best accomplished by implementing the model in a common computing tool such as Microsoft Excel. Excel is readily available and accessible to most system analysts, but it is not designed for straightforward implementation of a Monte Carlo–based method. Using a Monte Carlo algorithm requires in-spreadsheet scripting and statistical analyses or the use of add-ons such as Crystal Ball. An alternative method uses propagation of error calculations in the existing Excel-based system to estimate system cost uncertainty. This method has the advantage of using Microsoft Excel as is, but it requires the use of simplifying assumptions. These assumptions do not necessarily bring into question the analytical results. In fact, the

  12. Improving process representation in conceptual hydrological model calibration using climate simulations

    NASA Astrophysics Data System (ADS)

    Minville, Marie; Cartier, Dominique; Guay, Catherine; Leclaire, Louis-Alexandre; Audet, Charles; Le Digabel, Sébastien; Merleau, James

    2014-06-01

    Different sets of calibrated model parameters can yield divergent hydrological simulations which in turn can lead to different operational decisions or scientific conclusions. In order to obtain reliable hydrological results, proper calibration is therefore fundamental. This article proposes a new calibration approach for conceptual hydrological models based on the paradigm that hydrological process representation, along with the reproduction of observed streamflows, need to be taken into account when assessing the performance of a hydrological model. Several studies have shown that complementary data can be used to improve hydrological process representation and make hydrological modeling more robust. In the current study, the process of interest is actual evapotranspiration (AET). In order to obtain a more realistic representation of AET, meteorological variables and the AET mean annual cycle simulated by a regional climate model (RCM) driven by reanalysis are used to impose constraints during the optimization procedure. This calibration strategy is compared to a second strategy which relies on AET derived from reference data and to the classical approach based solely on the reproduction of observed discharges. The different methodologies are applied to calibrate the lumped conceptual model HSAMI, used operationally at Hydro-Québec, for six Canadian snow-dominated basins with various hydrometeorological and physiographical characteristics.

  13. Rubber airplane: Constraint-based component-modeling for knowledge representation in computer-aided conceptual design

    NASA Technical Reports Server (NTRS)

    Kolb, Mark A.

    1990-01-01

    Viewgraphs on Rubber Airplane: Constraint-based Component-Modeling for Knowledge Representation in Computer Aided Conceptual Design are presented. Topics covered include: computer aided design; object oriented programming; airfoil design; surveillance aircraft; commercial aircraft; aircraft design; and launch vehicles.

  14. Conceptual melt models: the past or valuable tools for future scenarios? (Invited)

    NASA Astrophysics Data System (ADS)

    Pellicciotti, F.; Konz, M.; Carenzo, M.

    2010-12-01

    Physically based models represent the physics of the system adequately but require large amounts of input data, whereas conceptual models can be driven by less input data but rely on empirical parameters and simplification of processes. A consistent amount of recent cryospheric research has focused on understanding the interaction between glaciers and climate and the response of glacierised catchments to changes in climate. A number of melt models have been developed for this purpose and applied at various temporal and spatial scales. Validation is also conducted with data sets of different type, quality and duration. As a result, assessment of models predictive skills and intercomparison of performance is difficult and results in uncertainties that have been rarely assessed. In this presentation, we discuss which models are better suited to study the impact of a changing climate on glaciers and snow cover at various spatial scales and temporal resolution. We show that energy balance models do not necessary out-perform enhanced temperature-index models, especially at the distributed scale, and demonstrate that the latter models are robust when applied in the same climatic region. A major objection to the use of empirical models for climate change studies is that they rely on calibrated parameters. We show that parameters controlling the spatial distribution of meteorological input are more important than those related to the model structure, are site specific and are a major source of uncertainty. Energy-balance models are also more sensitive to changes in air temperature than more conceptual models. We also discuss the robustness of various type of melt models recently put forward in the literature and assess their performance in terms of precision, accuracy and transferability using a Monte Carlo approach. All three evaluation criteria are affected by the temporal resolution of the simulations. Finally, we demonstrate that only a combination of different data

  15. . Ecological conceptual models: a framework and case study on ecosystem management for South Florida sustainability

    USGS Publications Warehouse

    Gentile, J.H.; Harwell, M.A.; Cropper, W.; Harwell, C. C.; DeAngelis, Donald L.; Davis, S.; Ogden, J.C.; Lirman, D.

    2001-01-01

    The Everglades and South Florida ecosystems are the focus of national and international attention because of their current degraded and threatened state. Ecological risk assessment, sustainability and ecosystem and adaptive management principles and processes are being used nationally as a decision and policy framework for a variety of types of ecological assessments. The intent of this study is to demonstrate the application of these paradigms and principles at a regional scale. The effects-directed assessment approach used in this study consists of a retrospective, eco-epidemiological phase to determine the causes for the current conditions and a prospective predictive risk-based assessment using scenario analysis to evaluate future options. Embedded in these assessment phases is a process that begins with the identification of goals and societal preferences which are used to develop an integrated suite of risk-based and policy relevant conceptual models. Conceptual models are used to illustrate the linkages among management (societal) actions, environmental stressors, and societal/ecological effects, and provide the basis for developing and testing causal hypotheses. These models, developed for a variety of landscape units and their drivers, stressors, and endpoints, are used to formulate hypotheses to explain the current conditions. They are also used as the basis for structuring management scenarios and analyses to project the temporal and spatial magnitude of risk reduction and system recovery. Within the context of recovery, the conceptual models are used in the initial development of performance criteria for those stressors that are determined to be most important in shaping the landscape, and to guide the use of numerical models used to develop quantitative performance criteria in the scenario analysis. The results will be discussed within an ecosystem and adaptive management framework that provides the foundation for decision making.

  16. A conceptual model of primary productivity in shallow streams using biomass simulation. Technical completion report

    SciTech Connect

    Elliott, J.C.; McDonnell, A.J.

    1982-06-01

    A conceptual model for primary productivity was developed for application to rooted aquatic macrophytes in streams to assist studies of eutrophication and control of water quality in supplementing outputs of dissolved oxygen (DO) models of pollution loads. This model included a first-order differential equation of biomass, with specific rates for photosynthesis, respiration, and death. A model component was developed to describe available light spatially/temporally in the weed bed, as reduced from extraterrestrial solar radiation. A DO model component included terms for photosynthetic production, plant respiration, and a benthal sink due to dead plant matter decay. The latter, a first-order exponential oxygen sink, had not been previously included in DO models.

  17. Empirical evaluation of the conceptual model underpinning a regional aquatic long-term monitoring program using causal modelling

    USGS Publications Warehouse

    Irvine, Kathryn M.; Miller, Scott; Al-Chokhachy, Robert K.; Archer, Erik; Roper, Brett B.; Kershner, Jeffrey L.

    2015-01-01

    Conceptual models are an integral facet of long-term monitoring programs. Proposed linkages between drivers, stressors, and ecological indicators are identified within the conceptual model of most mandated programs. We empirically evaluate a conceptual model developed for a regional aquatic and riparian monitoring program using causal models (i.e., Bayesian path analysis). We assess whether data gathered for regional status and trend estimation can also provide insights on why a stream may deviate from reference conditions. We target the hypothesized causal pathways for how anthropogenic drivers of road density, percent grazing, and percent forest within a catchment affect instream biological condition. We found instream temperature and fine sediments in arid sites and only fine sediments in mesic sites accounted for a significant portion of the maximum possible variation explainable in biological condition among managed sites. However, the biological significance of the direct effects of anthropogenic drivers on instream temperature and fine sediments were minimal or not detected. Consequently, there was weak to no biological support for causal pathways related to anthropogenic drivers’ impact on biological condition. With weak biological and statistical effect sizes, ignoring environmental contextual variables and covariates that explain natural heterogeneity would have resulted in no evidence of human impacts on biological integrity in some instances. For programs targeting the effects of anthropogenic activities, it is imperative to identify both land use practices and mechanisms that have led to degraded conditions (i.e., moving beyond simple status and trend estimation). Our empirical evaluation of the conceptual model underpinning the long-term monitoring program provided an opportunity for learning and, consequently, we discuss survey design elements that require modification to achieve question driven monitoring, a necessary step in the practice of

  18. Evolution of the conceptual model of unsaturated zone hydrology at yucca mountain, nevada

    SciTech Connect

    Flint, A. L.; Flint, L. E.; Bodvarsson, G. S.; Kwicklis, E. M.; Fabryka-Martin, J.

    2001-02-01

    Yucca Mountain is an arid site proposed for consideration as the United States' first underground high-level radioactive waste repository. Low rainfall (approximately 170 mm/yr) and a thick unsaturated zone (500-1000 m) are important physical attributes of the site because the quantity of water likely to reach the waste and the paths and rates of movement of the water to the saturated zone under future climates would be major factors in controlling the concentrations and times of arrival of radionuclides at the surrounding accessible environment. The framework for understanding the hydrologic processes that occur at this site and that control how quickly water will penetrate through the unsaturated zone to the water table has evolved during the past 15 yr. Early conceptual models assumed that very small volumes of water infiltrated into the bedrock (0.5-4.5 mm/yr, or 2-3 percent of rainfall), that much of the infiltrated water flowed laterally within the upper nonwelded units because o f capillary barrier effects, and that the remaining water flowed down faults with a small amount flowing through the matrix of the lower welded, fractured rocks. It was believed that the matrix had to be saturated for fractures to show. However, accumulating evidence indicated that infiltration rates were higher than initially estimated, such as infiltration modeling based on neutron borehole data, bomb-pulse isotopes deep in the mountain, perched water analyses and thermal analyses. Mechanisms supporting lateral diversion did not apply at these higher fluxes, and the flux calculated in the lower welded unit exceeded the conductivity of the matrix, implying vertical flow of water into the high permeability fractures of the potential repository host rock, and disequilibrium between matrix and fracture water potentials. The development of numerical modeling methods and parameter values evolved concurrently with the conceptual model in order to account for the observed field data

  19. Evolution of the conceptual model of unsaturated zone hydrology at Yucca Mountain, Nevada

    USGS Publications Warehouse

    Flint, Alan L.; Flint, Lorraine E.; Bodvarsson, Gudmundur S.; Kwicklis, Edward M.; Fabryka-Martin, June

    2001-01-01

    Yucca Mountain is an arid site proposed for consideration as the United States’ first underground high-level radioactive waste repository. Low rainfall (approximately 170 mm/yr) and a thick unsaturated zone (500–1000 m) are important physical attributes of the site because the quantity of water likely to reach the waste and the paths and rates of movement of the water to the saturated zone under future climates would be major factors in controlling the concentrations and times of arrival of radionuclides at the surrounding accessible environment. The framework for understanding the hydrologic processes that occur at this site and that control how quickly water will penetrate through the unsaturated zone to the water table has evolved during the past 15 yr. Early conceptual models assumed that very small volumes of water infiltrated into the bedrock (0.5–4.5 mm/yr, or 2–3 percent of rainfall), that much of the infiltrated water flowed laterally within the upper nonwelded units because of capillary barrier effects, and that the remaining water flowed down faults with a small amount flowing through the matrix of the lower welded, fractured rocks. It was believed that the matrix had to be saturated for fractures to flow. However, accumulating evidence indicated that infiltration rates were higher than initially estimated, such as infiltration modeling based on neutron borehole data, bomb-pulse isotopes deep in the mountain, perched water analyses and thermal analyses. Mechanisms supporting lateral diversion did not apply at these higher fluxes, and the flux calculated in the lower welded unit exceeded the conductivity of the matrix, implying vertical flow of water in the high permeability fractures of the potential repository host rock, and disequilibrium between matrix and fracture water potentials. The development of numerical modeling methods and parameter values evolved concurrently with the conceptual model in order to account for the observed field data

  20. Applying a Cognitive-Affective Model of Conceptual Change to Professional Development

    NASA Astrophysics Data System (ADS)

    Ebert, Ellen K.; Crippen, Kent J.

    2010-04-01

    This study evaluated Gregoire’s (2003) Cognitive-Affective Conceptual Change model (CAMCC) for predicting and assessing conceptual change in science teachers engaged in a long-term professional development project set in a large school district in the southwestern United States. A multiple case study method with data from three teacher participants was used to understand the process of integrating and applying a reform message of inquiry based science teaching. Data sources included: responses to example teaching scenarios, reflective essays, lesson plans, classroom observations, and action research projects. Findings show that the CAMCC functioned well in predicting how these teachers made decisions that impacted how they processed the reform message. When the reform message was communicated in such a way as to initiate stress appraisal, conceptual change occurred, producing changes in classroom practice. If the reform message did not initiate stress appraisal, teachers rejected the professional development message and developed heuristic responses. In order to further research and improve practice, propositions for assessments related to the CAMCC are provided.

  1. Conceptual design and analysis of a dynamic scale model of the Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Davis, D. A.; Gronet, M. J.; Tan, M. K.; Thorne, J.

    1994-01-01

    This report documents the conceptual design study performed to evaluate design options for a subscale dynamic test model which could be used to investigate the expected on-orbit structural dynamic characteristics of the Space Station Freedom early build configurations. The baseline option was a 'near-replica' model of the SSF SC-7 pre-integrated truss configuration. The approach used to develop conceptual design options involved three sets of studies: evaluation of the full-scale design and analysis databases, conducting scale factor trade studies, and performing design sensitivity studies. The scale factor trade study was conducted to develop a fundamental understanding of the key scaling parameters that drive design, performance and cost of a SSF dynamic scale model. Four scale model options were estimated: 1/4, 1/5, 1/7, and 1/10 scale. Prototype hardware was fabricated to assess producibility issues. Based on the results of the study, a 1/4-scale size is recommended based on the increased model fidelity associated with a larger scale factor. A design sensitivity study was performed to identify critical hardware component properties that drive dynamic performance. A total of 118 component properties were identified which require high-fidelity replication. Lower fidelity dynamic similarity scaling can be used for non-critical components.

  2. Bayesian Assessment of the Uncertainties of Estimates of a Conceptual Rainfall-Runoff Model Parameters

    NASA Astrophysics Data System (ADS)

    Silva, F. E. O. E.; Naghettini, M. D. C.; Fernandes, W.

    2014-12-01

    This paper evaluated the uncertainties associated with the estimation of the parameters of a conceptual rainfall-runoff model, through the use of Bayesian inference techniques by Monte Carlo simulation. The Pará River sub-basin, located in the upper São Francisco river basin, in southeastern Brazil, was selected for developing the studies. In this paper, we used the Rio Grande conceptual hydrologic model (EHR/UFMG, 2001) and the Markov Chain Monte Carlo simulation method named DREAM (VRUGT, 2008a). Two probabilistic models for the residues were analyzed: (i) the classic [Normal likelihood - r ≈ N (0, σ²)]; and (ii) a generalized likelihood (SCHOUPS & VRUGT, 2010), in which it is assumed that the differences between observed and simulated flows are correlated, non-stationary, and distributed as a Skew Exponential Power density. The assumptions made for both models were checked to ensure that the estimation of uncertainties in the parameters was not biased. The results showed that the Bayesian approach proved to be adequate to the proposed objectives, enabling and reinforcing the importance of assessing the uncertainties associated with hydrological modeling.

  3. A Conceptual Life-History Model for Pallid and Shovelnose Sturgeon

    USGS Publications Warehouse

    Wildhaber, Mark L.; DeLonay, Aaron J.; Papoulias, Diana M.; Galat, David L.; Jacobson, Robert B.; Simpkins, Darin G.; Braaten, P. J.; Korschgen, Carl E.; Mac, Michael J.

    2007-01-01

    Intensive management of the Missouri and Mississippi Rivers has resulted in dramatic physical changes to these rivers. These changes have been implicated as causative agents in the decline of pallid sturgeon. The pallid sturgeon, federally listed as endangered, is endemic to the turbid waters of the Missouri River and the Lower Mississippi River. The sympatric shovelnose sturgeon historically was more common and widespread than the pallid sturgeon. Habitat alteration, river regulation, pollution, and over-harvest have resulted in the now predictable patterns of decline and localized extirpation of sturgeon across species and geographic areas. Symptomatic of this generalized pattern of decline is poor reproductive success, and low or no recruitment of wild juveniles to the adult population. The purpose of this report is to introduce a conceptual life-history model of the factors that affect reproduction, growth, and survival of shovelnose and pallid sturgeons. The conceptual model provided here was developed to organize the understanding about the complex life history of Scaphirhynchus sturgeons. It was designed to be used for communication, planning, and to provide the structure for a population-forecasting model. These models are intended to be dynamic and responsive to new information and changes in river management, thereby providing scientists, stakeholders, and managers with ways to improve understanding of the effects of management actions on the ecological requirements of Scaphirhynchus sturgeons. As new scientific knowledge becomes available, it could be included in the model in many ways at various integration levels.

  4. A hydrogeophysical conceptual model of Mount Toondina impact crater, South Australia

    NASA Astrophysics Data System (ADS)

    Dressler, Andrew Kelly

    Mount Toondina, South Australia is an impact crater that currently has groundwater discharging through evapotranspiration, but formerly had eight springs or more flowing around the crater ring. Using field geophysical and geochemical data, a hydrogeophysical conceptual model was developed that suggests that advection of groundwater to the surface through a sandstone layer is the dominant flow mechanism for the system, creating a ring of vegetation at the surface, although faults provide controls over some spring locations. The data also suggest that sufficient fluid density contrast combined with a vertical permeability structure may allow free convection to occur in the impact crater. The conceptual model was tested by developing numerical models to evaluate the permeability structure and the potential for mixed convection in the Mount Toondina system. The FEFLOW models suggest that the Mount Toondina impact crater spring system is controlled by mixed convective flow from the subsurface to the ring of vegetation around the springs which maintains brackish conditions relative to adjacent saline conditions. The models indicated that convective processes result throughout the crater although the character of convection is controlled by the relative permeability of the formations. The results can be applied to better manage flora and fauna in the Mount Toondina area and help to interpret potential for groundwater flow in and around other impact craters.

  5. Keeping it simple: a conceptual model of DOC dynamics in a subarctic alpine catchment

    NASA Astrophysics Data System (ADS)

    Lessels, J. S.; Tetzlaff, D.; Carey, S. K.; Soulsby, C.

    2013-12-01

    Understanding hydrological processes in subarctic alpine catchments characterised with discontinuous permafrost is important in order to understand carbon exports. Subarctic catchments have large storages of carbon in organic and permafrost soils. Active layer depth is one of the largest controlling factors of the release of dissolved organic carbon (DOC) due to its control on runoff pathways. Therefore, any change of this depth will affect the amount of DOC mobilised from these catchments. Simple low parameterised conceptual models offer the ability to characterise hydrological processes and linked DOC dynamics without introducing many of the uncertainties linked to high parameterised models. Lumped models can also be used to identify sources of DOC within catchments. Here, we investigate hydrological sources, flow pathways and consequently DOC dynamics in the Granger Basin, Canada, a subarctic alpine catchment using data collected from 2001 to 2008. The catchment is distinguished by aspect dependant discontinuous permafrost and seasonal frost, compounded further by differences in soil and vegetation types. Applying a simple low parameterised conceptual model allowed identification of the dominant flow paths of the main hydrological response units. The results showed that it was necessary to include active layer dynamics combined with aspect to represent the hydrological and DOC dynamics. The model provides information on the effect of climatic conditions on DOC releases. By identifying the key flow paths and relating these to spring freshet DOC exports over multiple years it is possible to gain an insight of the how climatic changes might affect hydrological processes within subarctic catchments.

  6. Chlorine-36 data at Yucca Mountain: Statistical tests of conceptual models for unsaturated-zone flow

    USGS Publications Warehouse

    Campbell, K.; Wolfsberg, A.; Fabryka-Martin, J.; Sweetkind, D.

    2003-01-01

    An extensive set of chlorine-36 (36Cl) data has been collected in the Exploratory Studies Facility (ESF), an 8-km-long tunnel at Yucca Mountain, Nevada, for the purpose of developing and testing conceptual models of flow and transport in the unsaturated zone (UZ) at this site. At several locations, the measured values of 36Cl/Cl ratios for salts leached from rock samples are high enough to provide strong evidence that at least a small component of bomb-pulse 36Cl, fallout from atmospheric testing of nuclear devices in the 1950s and 1960s, was measured, implying that some fraction of the water traveled from the ground surface through 200-300 m of unsaturated rock to the level of the ESF during the last 50 years. These data are analyzed here using a formal statistical approach based on log-linear models to evaluate alternative conceptual models for the distribution of such fast flow paths. The most significant determinant of the presence of bomb-pulse 36Cl in a sample from the welded Topopah Spring unit (TSw) is the structural setting from which the sample was collected. Our analysis generally supports the conceptual model that a fault that cuts through the nonwelded Paintbrush tuff unit (PTn) that overlies the TSw is required in order for bomb-pulse 36Cl to be transmitted to the sample depth in less than 50 years. Away from PTn-cutting faults, the ages of water samples at the ESF appear to be a strong function of the thickness of the nonwelded tuff between the ground surface and the ESF, due to slow matrix flow in that unit. ?? 2002 Elsevier Science B.V. All rights reserved.

  7. Reducing structural uncertainty in conceptual hydrological modeling in the semi-arid Andes

    NASA Astrophysics Data System (ADS)

    Hublart, P.; Ruelland, D.; Dezetter, A.; Jourde, H.

    2014-10-01

    The use of lumped, conceptual models in hydrological impact studies requires placing more emphasis on the uncertainty arising from deficiencies and/or ambiguities in the model structure. This study provides an opportunity to combine a multiple-hypothesis framework with a multi-criteria assessment scheme to reduce structural uncertainty in the conceptual modeling of a meso-scale Andean catchment (1515 km2) over a 30 year period (1982-2011). The modeling process was decomposed into six model-building decisions related to the following aspects of the system behavior: snow accumulation and melt, runoff generation, redistribution and delay of water fluxes, and natural storage effects. Each of these decisions was provided with a set of alternative modeling options, resulting in a total of 72 competing model structures. These structures were calibrated using the concept of Pareto optimality with three criteria pertaining to streamflow simulations and one to the seasonal dynamics of snow processes. The results were analyzed in the four-dimensional space of performance measures using a fuzzy c-means clustering technique and a differential split sample test, leading to identify 14 equally acceptable model hypotheses. A filtering approach was then applied to these best-performing structures in order to minimize the overall uncertainty envelope while maximizing the number of enclosed observations. This led to retain 8 model hypotheses as a representation of the minimum structural uncertainty that could be obtained with this modeling framework. Future work to better consider model predictive uncertainty should include a proper assessment of parameter equifinality and data errors, as well as the testing of new or refined hypotheses to allow for the use of additional auxiliary observations.

  8. Reducing structural uncertainty in conceptual hydrological modelling in the semi-arid Andes

    NASA Astrophysics Data System (ADS)

    Hublart, P.; Ruelland, D.; Dezetter, A.; Jourde, H.

    2015-05-01

    The use of lumped, conceptual models in hydrological impact studies requires placing more emphasis on the uncertainty arising from deficiencies and/or ambiguities in the model structure. This study provides an opportunity to combine a multiple-hypothesis framework with a multi-criteria assessment scheme to reduce structural uncertainty in the conceptual modelling of a mesoscale Andean catchment (1515 km2) over a 30-year period (1982-2011). The modelling process was decomposed into six model-building decisions related to the following aspects of the system behaviour: snow accumulation and melt, runoff generation, redistribution and delay of water fluxes, and natural storage effects. Each of these decisions was provided with a set of alternative modelling options, resulting in a total of 72 competing model structures. These structures were calibrated using the concept of Pareto optimality with three criteria pertaining to streamflow simulations and one to the seasonal dynamics of snow processes. The results were analyzed in the four-dimensional (4-D) space of performance measures using a fuzzy c-means clustering technique and a differential split sample test, leading to identify 14 equally acceptable model hypotheses. A filtering approach was then applied to these best-performing structures in order to minimize the overall uncertainty envelope while maximizing the number of enclosed observations. This led to retain eight model hypotheses as a representation of the minimum structural uncertainty that could be obtained with this modelling framework. Future work to better consider model predictive uncertainty should include a proper assessment of parameter equifinality and data errors, as well as the testing of new or refined hypotheses to allow for the use of additional auxiliary observations.

  9. Alternative conceptual models and codes for unsaturated flow in fractured tuff: Preliminary assessments for GWTT-95

    SciTech Connect

    Ho, C.K.; Altman, S.J.; Arnold, B.W.

    1995-09-01

    Groundwater travel time (GWTT) calculations will play an important role in addressing site-suitability criteria for the potential high-level nuclear waste repository at Yucca Mountain,Nevada. In support of these calculations, Preliminary assessments of the candidate codes and models are presented in this report. A series of benchmark studies have been designed to address important aspects of modeling flow through fractured media representative of flow at Yucca Mountain. Three codes (DUAL, FEHMN, and TOUGH 2) are compared in these benchmark studies. DUAL is a single-phase, isothermal, two-dimensional flow simulator based on the dual mixed finite element method. FEHMN is a nonisothermal, multiphase, multidimensional simulator based primarily on the finite element method. TOUGH2 is anon isothermal, multiphase, multidimensional simulator based on the integral finite difference method. Alternative conceptual models of fracture flow consisting of the equivalent continuum model (ECM) and the dual permeability (DK) model are used in the different codes.

  10. Rapid implementation of advanced constitutive models

    NASA Astrophysics Data System (ADS)

    Starman, Bojan; Halilovič, Miroslav; Vrh, Marko; Štok, Boris

    2013-12-01

    This paper presents a methodology based on the NICE integration scheme [1, 2] for simple and rapid numerical implementation of a class of plasticity constitutive models. In this regard, an algorithm is purposely developed for the implementation of newly developed advanced constitutive models into explicit finite element framework. The methodology follows the organization of the problem state variables into an extended form, which allows the constitutive models' equations to be organized in such a way, that the algorithm can be optionally extended with minimal effort to integrate also evolution equations related to a description of other specific phenomena, such as damage, distortional hardening, phase transitions, degradation etc. To confirm simplicity of the program implementation, computational robustness, effectiveness and improved accuracy of the implemented integration algorithm, a deep drawing simulation of the cylindrical cup is considered as the case study, performed in ABAQUS/Explicit. As a fairly complex considered model, the YLD2004-18p model [3, 4] is first implemented via external subroutine VUMAT. Further, to give additional proof of the simplicity of the proposed methodology, a combination of the YLD2004-18p model and Gurson-Tvergaard-Needleman model (GTN) is considered. As demonstrated, the implementation is really obtained in a very simple way.

  11. Integrated approach to model decomposed flow hydrograph using artificial neural network and conceptual techniques

    NASA Astrophysics Data System (ADS)

    Jain, Ashu; Srinivasulu, Sanaga

    2006-02-01

    This paper presents the findings of a study aimed at decomposing a flow hydrograph into different segments based on physical concepts in a catchment, and modelling different segments using different technique viz. conceptual and artificial neural networks (ANNs). An integrated modelling framework is proposed capable of modelling infiltration, base flow, evapotranspiration, soil moisture accounting, and certain segments of the decomposed flow hydrograph using conceptual techniques and the complex, non-linear, and dynamic rainfall-runoff process using ANN technique. Specifically, five different multi-layer perceptron (MLP) and two self-organizing map (SOM) models have been developed. The rainfall and streamflow data derived from the Kentucky River catchment were employed to test the proposed methodology and develop all the models. The performance of all the models was evaluated using seven different standard statistical measures. The results obtained in this study indicate that (a) the rainfall-runoff relationship in a large catchment consists of at least three or four different mappings corresponding to different dynamics of the underlying physical processes, (b) an integrated approach that models the different segments of the decomposed flow hydrograph using different techniques is better than a single ANN in modelling the complex, dynamic, non-linear, and fragmented rainfall runoff process, (c) a simple model based on the concept of flow recession is better than an ANN to model the falling limb of a flow hydrograph, and (d) decomposing a flow hydrograph into the different segments corresponding to the different dynamics based on the physical concepts is better than using the soft decomposition employed using SOM.

  12. Constraining performance assessment models with tracer test results: a comparison between two conceptual models

    NASA Astrophysics Data System (ADS)

    McKenna, Sean A.; Selroos, Jan-Olof

    Tracer tests are conducted to ascertain solute transport parameters of a single rock feature over a 5-m transport pathway. Two different conceptualizations of double-porosity solute transport provide estimates of the tracer breakthrough curves. One of the conceptualizations (single-rate) employs a single effective diffusion coefficient in a matrix with infinite penetration depth. However, the tracer retention between different flow paths can vary as the ratio of flow-wetted surface to flow rate differs between the path lines. The other conceptualization (multirate) employs a continuous distribution of multiple diffusion rate coefficients in a matrix with variable, yet finite, capacity. Application of these two models with the parameters estimated on the tracer test breakthrough curves produces transport results that differ by orders of magnitude in peak concentration and time to peak concentration at the performance assessment (PA) time and length scales (100,000 years and 1,000 m). These differences are examined by calculating the time limits for the diffusive capacity to act as an infinite medium. These limits are compared across both conceptual models and also against characteristic times for diffusion at both the tracer test and PA scales. Additionally, the differences between the models are examined by re-estimating parameters for the multirate model from the traditional double-porosity model results at the PA scale. Results indicate that for each model the amount of the diffusive capacity that acts as an infinite medium over the specified time scale explains the differences between the model results and that tracer tests alone cannot provide reliable estimates of transport parameters for the PA scale. Results of Monte Carlo runs of the transport models with varying travel times and path lengths show consistent results between models and suggest that the variation in flow-wetted surface to flow rate along path lines is insignificant relative to variability in

  13. Conceptual framework for model-based analysis of residence time distribution in twin-screw granulation.

    PubMed

    Kumar, Ashish; Vercruysse, Jurgen; Vanhoorne, Valérie; Toiviainen, Maunu; Panouillot, Pierre-Emmanuel; Juuti, Mikko; Vervaet, Chris; Remon, Jean Paul; Gernaey, Krist V; De Beer, Thomas; Nopens, Ingmar

    2015-04-25

    Twin-screw granulation is a promising continuous alternative for traditional batchwise wet granulation processes. The twin-screw granulator (TSG) screws consist of transport and kneading element modules. Therefore, the granulation to a large extent is governed by the residence time distribution within each module where different granulation rate processes dominate over others. Currently, experimental data is used to determine the residence time distributions. In this study, a conceptual model based on classical chemical engineering methods is proposed to better understand and simulate the residence time distribution in a TSG. The experimental data were compared with the proposed most suitable conceptual model to estimate the parameters of the model and to analyse and predict the effects of changes in number of kneading discs and their stagger angle, screw speed and powder feed rate on residence time. The study established that the kneading block in the screw configuration acts as a plug-flow zone inside the granulator. Furthermore, it was found that a balance between the throughput force and conveying rate is required to obtain a good axial mixing inside the twin-screw granulator. Although the granulation behaviour is different for other excipients, the experimental data collection and modelling methods applied in this study are generic and can be adapted to other excipients. PMID:25698071

  14. A Knowledge-Based and Model-Driven Requirements Engineering Approach to Conceptual Satellite Design

    NASA Astrophysics Data System (ADS)

    Dos Santos, Walter A.; Leonor, Bruno B. F.; Stephany, Stephan

    Satellite systems are becoming even more complex, making technical issues a significant cost driver. The increasing complexity of these systems makes requirements engineering activities both more important and difficult. Additionally, today's competitive pressures and other market forces drive manufacturing companies to improve the efficiency with which they design and manufacture space products and systems. This imposes a heavy burden on systems-of-systems engineering skills and particularly on requirements engineering which is an important phase in a system's life cycle. When this is poorly performed, various problems may occur, such as failures, cost overruns and delays. One solution is to underpin the preliminary conceptual satellite design with computer-based information reuse and integration to deal with the interdisciplinary nature of this problem domain. This can be attained by taking a model-driven engineering approach (MDE), in which models are the main artifacts during system development. MDE is an emergent approach that tries to address system complexity by the intense use of models. This work outlines the use of SysML (Systems Modeling Language) and a novel knowledge-based software tool, named SatBudgets, to deal with these and other challenges confronted during the conceptual phase of a university satellite system, called ITASAT, currently being developed by INPE and some Brazilian universities.

  15. Conceptual model of sedimentation in the Sacramento-San Joaquin River Delta

    USGS Publications Warehouse

    Schoellhamer, David H.; Wright, Scott A.; Drexler, Judith Z.

    2012-01-01

    Sedimentation in the Sacramento–San Joaquin River Delta builds the Delta landscape, creates benthic and pelagic habitat, and transports sediment-associated contaminants. Here we present a conceptual model of sedimentation that includes submodels for river supply from the watershed to the Delta, regional transport within the Delta and seaward exchange, and local sedimentation in open water and marsh habitats. The model demonstrates feedback loops that affect the Delta ecosystem. Submerged and emergent marsh vegetation act as ecosystem engineers that can create a positive feedback loop by decreasing suspended sediment, increasing water column light, which in turn enables more vegetation. Sea-level rise in open water is partially countered by a negative feedback loop that increases deposition if there is a net decrease in hydrodynamic energy. Manipulation of regional sediment transport is probably the most feasible method to control suspended sediment and thus turbidity. The conceptual model is used to identify information gaps that need to be filled to develop an accurate sediment transport model.

  16. Conceptual model for transport processes in the Culebra Dolomite Member, Rustler Formation

    SciTech Connect

    Holt, R.M.

    1997-08-01

    The Culebra Dolomite Member of the Rustler Formation represents a possible pathway for contaminants from the Waste Isolation Pilot Plant underground repository to the accessible environment. The geologic character of the Culebra is consistent with a double-porosity, multiple-rate model for transport in which the medium is conceptualized as consisting of advective porosity, where solutes are carried by the groundwater flow, and fracture-bounded zones of diffusive porosity, where solutes move through slow advection or diffusion. As the advective travel length or travel time increases, the nature of transport within a double-porosity medium changes. This behavior is important for chemical sorption, because the specific surface area per unit mass of the diffusive porosity is much greater than in the advective porosity. Culebra transport experiments conducted at two different length scales show behavior consistent with a multiple-rate, double-porosity conceptual model for Culebra transport. Tracer tests conducted on intact core samples from the Culebra show no evidence of significant diffusion, suggesting that at the core scale the Culebra can be modeled as a single-porosity medium where only the advective porosity participates in transport. Field tracer tests conducted in the Culebra show strong double-porosity behavior that is best explained using a multiple-rate model.

  17. Description and evaluation of a mechanistically based conceptual model for spall

    SciTech Connect

    Hansen, F.D.; Knowles, M.K.; Thompson, T.W.

    1997-08-01

    A mechanistically based model for a possible spall event at the WIPP site is developed and evaluated in this report. Release of waste material to the surface during an inadvertent borehole intrusion is possible if future states of the repository include high gas pressure and waste material consisting of fine particulates having low mechanical strength. The conceptual model incorporates the physics of wellbore hydraulics coupled to transient gas flow to the intrusion borehole, and mechanical response of the waste. Degraded waste properties using of the model. The evaluations include both numerical and analytical implementations of the conceptual model. A tensile failure criterion is assumed appropriate for calculation of volumes of waste experiencing fragmentation. Calculations show that for repository gas pressures less than 12 MPa, no tensile failure occurs. Minimal volumes of material experience failure below gas pressure of 14 MPa. Repository conditions dictate that the probability of gas pressures exceeding 14 MPa is approximately 1%. For these conditions, a maximum failed volume of 0.25 m{sup 3} is calculated.

  18. The International Classification of Functioning, Disability and Health: a unifying model for the conceptual description of physical and rehabilitation medicine.

    PubMed

    Stucki, Gerold; Melvin, John

    2007-05-01

    There is a need to develop a contemporary and internationally accepted conceptual description of physical and rehabilitation medicine (PRM). The process of evolving such a definition can now rely on the unifying conceptual model and taxonomy of the International Classification of Functioning, Disability and Health (ICF) and an ICF-based conceptual description of rehabilitation understood as a health strategy. The PRM section of the European Union of Medical Specialists (UEMS) has endorsed the application of the ICF as a unifying conceptual model for PRM and supports the process of moving towards an "ICF-based conceptual description and according definitions of PRM". With this goal in mind, the authors have developed a first tentative conceptual description in co-operation with the professional practice committee of the UEMS-PRM-section. A respective brief definition describes PRM as the medical specialty that, based on the assessment of functioning and including the diagnosis and treatment of health conditions, performs, applies and co-ordinates biomedical and engineering and a wide range of other interventions with the goal of optimizing functioning of people experiencing or likely to experience disability. Readers of the Journal of Rehabilitation Medicine are invited to contribute to the process of achieving an internationally accepted ICF-based conceptual description of PRM by submitting commentaries to the Editor of this journal.

  19. The International Classification of Functioning, Disability and Health (ICF): a unifying model for the conceptual description of the rehabilitation strategy.

    PubMed

    Stucki, Gerold; Cieza, Alarcos; Melvin, John

    2007-05-01

    An important basis for the successful development of rehabilitation practice and research is a conceptually sound description of rehabilitation understood as a health strategy based on a universally accepted conceptual model and taxonomy of human functioning. With the approval of the International Classification of Functioning, Disability and Health (ICF) by the World Health Assembly in 2001 and the reference to the ICF in the World Health Assembly's resolution on "Disability, including prevention, management and rehabilitation" in 2005, we can now rely on a universally accepted conceptual model. It is thus time to initiate the process of evolving an ICF-based conceptual description that can serve as a basis for similar conceptual descriptions and according definitions of the professions applying the rehabilitation strategy and of distinct scientific fields of human functioning and rehabilitation research. In co-operation with the Physical and Rehabilitation Medicine (PRM) section of the European Union of Medical Specialists (UEMS) and its professional practice committee, we present a first tentative version of an ICF-based conceptual description in this paper. A brief definition describes rehabilitation as the health strategy applied by PRM and professionals in the health sector and across other sectors that aims to enable people with health conditions experiencing or likely to experience disability to achieve and maintain optimal functioning in interaction with the environment. Readers of the Journal of Rehabilitation Medicine are invited to contribute towards achieving an internationally accepted ICF-based conceptual description of rehabilitation by submitting commentaries to the Editor of this journal.

  20. Optimal observation network design for conceptual model discrimination and uncertainty reduction

    NASA Astrophysics Data System (ADS)

    Pham, Hai V.; Tsai, Frank T.-C.

    2016-02-01

    This study expands the Box-Hill discrimination function to design an optimal observation network to discriminate conceptual models and, in turn, identify a most favored model. The Box-Hill discrimination function measures the expected decrease in Shannon entropy (for model identification) before and after the optimal design for one additional observation. This study modifies the discrimination function to account for multiple future observations that are assumed spatiotemporally independent and Gaussian-distributed. Bayesian model averaging (BMA) is used to incorporate existing observation data and quantify future observation uncertainty arising from conceptual and parametric uncertainties in the discrimination function. In addition, the BMA method is adopted to predict future observation data in a statistical sense. The design goal is to find optimal locations and least data via maximizing the Box-Hill discrimination function value subject to a posterior model probability threshold. The optimal observation network design is illustrated using a groundwater study in Baton Rouge, Louisiana, to collect additional groundwater heads from USGS wells. The sources of uncertainty creating multiple groundwater models are geological architecture, boundary condition, and fault permeability architecture. Impacts of considering homoscedastic and heteroscedastic future observation data and the sources of uncertainties on potential observation areas are analyzed. Results show that heteroscedasticity should be considered in the design procedure to account for various sources of future observation uncertainty. After the optimal design is obtained and the corresponding data are collected for model updating, total variances of head predictions can be significantly reduced by identifying a model with a superior posterior model probability.

  1. Advances in Sun-Earth Connection Modeling

    NASA Astrophysics Data System (ADS)

    Ganguli, S. B.; Gavrishchaka, V. V.

    2003-06-01

    Space weather forecasting is a focus of a multidisciplinary research effort motivated by a sensitive dependence of many modern technologies on geospace conditions. Adequate understanding of the physics of the Sun-Earth connection and associated multi-scale magnetospheric and ionospheric processes is an essential part of this effort. Modern physical simulation models such as multimoment multifluid models with effective coupling from small-scale kinetic processes can provide valuable insight into the role of various physical mechanisms operating during geomagnetic storm/substorm activity. However, due to necessary simplifying assumptions, physical models are still not well suited for accurate real-time forecasting. Complimentary approach includes data-driven models capable of efficient processing of multi-scale spatio-temporal data. However, the majority of advanced nonlinear algorithms, including neural networks (NN), can encounter a set of problems called dimensionality curse when applied to high-dimensional data. Forecasting of rare/extreme events such as large geomagnetic storms/substorms is of the most practical importance but is also very challenging for many existing models. A very promising algorithm that combines the power of the best nonlinear techniques and tolerance to high-dimensional and incomplete data is support vector machine (SVM). We have summarized advantages of the SVM and described a hybrid model based on SVM and extreme value theory (EVT) for rare event forecasting. Results of the SVM application to substorm forecasting and future directions are discussed.

  2. A conceptual model to estimate cost effectiveness of the indoor environment improvements

    SciTech Connect

    Seppanen, Olli; Fisk, William J.

    2003-06-01

    Macroeconomic analyses indicate a high cost to society of a deteriorated indoor climate. The few example calculations performed to date indicate that measures taken to improve IEQ are highly cost-effective when health and productivity benefits are considered. We believe that cost-benefit analyses of building designs and operations should routinely incorporate health and productivity impacts. As an initial step, we developed a conceptual model that shows the links between improvements in IEQ and the financial gains from reductions in medical care and sick leave, improved work performance, lower employee turn over, and reduced maintenance due to fewer complaints.

  3. The relationship between the key elements of Donabedian's conceptual model within the field of assistive technology.

    PubMed

    Sund, Terje; Iwarsson, Susanne; Brandt, Åse

    2015-01-01

    Previous research has suggested that there is a relationship between the three key components of Donabedian's conceptual model for quality assessments: structure of care, process, and outcome of care. That is, structure predicted both process and outcome of care, and better processes predict better functional outcomes and user satisfaction. The results in this study involving samples of Danish and Norwegian scooter users indicate that structure predicts what goes on in the service delivery process. However, the results do not support that structural differences or differences in the service delivery process predict the outcomes of the scooter interventions. PMID:26294517

  4. Conceptual model for collision detection and avoidance for runway incursion prevention

    NASA Astrophysics Data System (ADS)

    Latimer, Bridgette A.

    The Federal Aviation Administration (FAA), National Transportation and Safety Board (NTSB), National Aeronautics and Space Administration (NASA), numerous corporate entities, and research facilities have each come together to determine ways to make air travel safer and more efficient. These efforts have resulted in the development of a concept known as the Next Generation (Next Gen) of Aircraft or Next Gen. The Next Gen concept promises to be a clear departure from the way in which aircraft operations are performed today. The Next Gen initiatives require that modifications are made to the existing National Airspace System (NAS) concept of operations, system level requirements, software (SW) and hardware (HW) requirements, SW and HW designs and implementations. A second example of the changes in the NAS is the shift away from air traffic controllers having the responsibility for separation assurance. In the proposed new scheme of free flight, each aircraft would be responsible for assuring that it is safely separated from surrounding aircraft. Free flight would allow the separation minima for enroute aircraft to be reduced from 2000 nautical miles (nm) to 1000 nm. Simply put "Free Flight is a concept of air traffic management that permits pilots and controllers to share information and work together to manage air traffic from pre-flight through arrival without compromising safety [107]." The primary goal of this research project was to create a conceptual model that embodies the essential ingredients needed for a collision detection and avoidance system. This system was required to operate in two modes: air traffic controller's perspective and pilot's perspective. The secondary goal was to demonstrate that the technologies, procedures, and decision logic embedded in the conceptual model were able to effectively detect and avoid collision risks from both perspectives. Embodied in the conceptual model are five distinct software modules: Data Acquisition, State

  5. Early psychosis, activity performance and social participation: a conceptual model to guide rehabilitation and recovery.

    PubMed

    Woodside, Harriet; Krupa, Terry; Pocock, Karen

    2007-01-01

    In this paper we present a conceptual model focusing on activity performance and social participation of individuals in the period prior to their first acute episodes of psychosis. The model was developed using the constructivist grounded theory method. Data from interviews and documents was collected from 25 primary participants. Interviews were also conducted with 15 members of the participants' support networks and six experts in the field of early psychosis and rehabilitation. The model illustrates how the core constructs of activity performance and social participation are set against the natural context and influenced by shifts in three determinants: faltering personal capacities, negotiating for success and risk factors. The model suggests rehabilitation and recovery practices in early intervention work. PMID:18018956

  6. a Conceptual Model for the Representation of Landforms Using Ontology Design Patterns

    NASA Astrophysics Data System (ADS)

    Guilbert, Eric; Moulin, Bernard; Cortés Murcia, Andrés

    2016-06-01

    A landform is an area of a terrain with its own recognisable shape. Its definition is often qualitative and inherently vague. Hence landforms are difficult to formalise in view of their extraction from a DTM. This paper presents a two-level framework for the representation of landforms. The objective is to provide a structure where landforms can be conceptually designed according to a common model which can be implemented. It follows the principle that landforms are not defined by geometrical characteristics but by salient features perceived by people. Hence, these salient features define a skeleton around which the landform is built. The first level of our model defines general concepts forming a landform prototype while the second level provides a model for the translation of these concepts and landform extraction on a DTM. The model is still under construction and preliminary results together with current developments are also presented.

  7. Advanced modeling of prompt fission neutrons

    SciTech Connect

    Talou, Patrick

    2009-01-01

    Theoretical and numerical studies of prompt fission neutrons are presented. The main results of the Los Alamos model often used in nuclear data evaluation work are reviewed briefly, and a preliminary assessment of uncertainties associated with the evaluated prompt fission neutron spectrum for n (0.5 MeV)+{sup 239}Pu is discussed. Advanced modeling of prompt fission neutrons is done by Monte Carlo simulations of the evaporation process of the excited primary fission fragments. The successive emissions of neutrons are followed in the statistical formalism framework, and detailed information, beyond average quantities, can be inferred. This approach is applied to the following reactions: {sup 252}Cf (sf), n{sub th} + {sup 239}Pu, n (0.5 MeV)+{sup 235}U, and {sup 236}Pu (sf). A discussion on the merits and present limitations of this approach concludes this presentation.

  8. Prospects for Advanced RF Theory and Modeling

    SciTech Connect

    Batchelor, D.B.

    1999-04-12

    This paper represents an attempt to express in print the contents of a rather philosophical review talk. The charge for the talk was not to summarize the present status of the field and what we can do, but to assess what we will need to do in the future and where the gaps are in fulfilling these needs. The objective was to be complete, covering all aspects of theory and modeling in all frequency regimes, although in the end the talk mainly focussed on the ion cyclotron range of frequencies (ICRF). In choosing which areas to develop, it is important to keep in mind who the customers for RF modeling are likely to be and what sorts of tasks they will need for RF to do. This occupies the first part of the paper. Then we examine each of the elements of a complete RF theory and try to identify the kinds of advances needed.

  9. Automatic generation of conceptual database design tools from data model specifications

    SciTech Connect

    Hong, Shuguang.

    1989-01-01

    The problems faced in the design and implementation of database software systems based on object-oriented data models are similar to that of other software design, i.e., difficult, complex, yet redundant effort. Automatic generation of database software system has been proposed as a solution to the problems. In order to generate database software system for a variety of object-oriented data models, two critical issues: data model specification and software generation, must be addressed. SeaWeed is a software system that automatically generates conceptual database design tools from data model specifications. A meta model has been defined for the specification of a class of object-oriented data models. This meta model provides a set of primitive modeling constructs that can be used to express the semantics, or unique characteristics, of specific data models. Software reusability has been adopted for the software generation. The technique of design reuse is utilized to derive the requirement specification of the software to be generated from data model specifications. The mechanism of code reuse is used to produce the necessary reusable software components. This dissertation presents the research results of SeaWeed including the meta model, data model specification, a formal representation of design reuse and code reuse, and the software generation paradigm.

  10. Conceptual heuristic models of the interrelationships between obesity and the occupational environment

    PubMed Central

    Pandalai, Sudha P; Schulte, Paul A; Miller, Diane B

    2015-01-01

    Objective Research and interventions targeting the relationship between work, its attendant occupational hazards, and obesity are evolving but merit further consideration in the public health arena. In this discussion paper, conceptual heuristic models are described examining the role of obesity as both a risk factor and health outcome in the occupational setting. Methods PubMed was searched using specific criteria from 2000 and onwards for evidence to support conceptual models in which obesity serves as a risk factor for occupational disease or an outcome of occupational exposures. Nine models are presented: four where obesity is a risk factor and five where it is an adverse effect. Results A broad range of work-related health effects are associated with obesity including musculoskeletal disorders, asthma, liver disease, and cardiovascular disease, among others. Obesity can be associated with occupational hazards such as shift work, sedentary work, job stress, and exposure to some chemicals. Conclusion Identification of combinations of risk factors pertinent to obesity in the occupational environment will provide important guidance for research and prevention. PMID:23588858

  11. Studying the teaching of kindness: A conceptual model for evaluating kindness education programs in schools.

    PubMed

    Kaplan, Deanna M; deBlois, Madeleine; Dominguez, Violeta; Walsh, Michele E

    2016-10-01

    Recent research suggests that school-based kindness education programs may benefit the learning and social-emotional development of youth and may improve school climate and school safety outcomes. However, how and to what extent kindness education programming influences positive outcomes in schools is poorly understood, and such programs are difficult to evaluate in the absence of a conceptual model for studying their effectiveness. In partnership with Kind Campus, a widely adopted school-based kindness education program that uses a bottom-up program framework, a methodology called concept mapping was used to develop a conceptual model for evaluating school-based kindness education programs from the input of 123 middle school students and approximately 150 educators, school professionals, and academic scholars. From the basis of this model, recommendations for processes and outcomes that would be useful to assess in evaluations of kindness education programs are made, and areas where additional instrument development may be necessary are highlighted. The utility of the concept mapping method as an initial step in evaluating other grassroots or non-traditional educational programming is also discussed. PMID:27376750

  12. A conceptual model of computerised hospital information system (CHIS) use in South Africa.

    PubMed

    Hanmer, Lyn A; Isaacs, Sedick; Roode, J Dewald

    2007-01-01

    The aim of this project is to contribute to limiting the risk of CHIS (computerised hospital information system) failure by identifying factors which are associated with the successful implementation of CHISs in district and regional hospitals in South Africa (SA). Case studies were conducted in four regional hospitals in the Western Cape province of SA to obtain data about user perceptions of the success or lack of success of the CHISs in use. A conceptual model of CHIS use has been developed based on the results of the case studies, in order to assist in the interpretation of the differing experiences across the hospitals. Key factors in the conceptual model are perception of usefulness of the CHIS and management commitment to ensuring CHIS success, which in turn are related to effective use of CHIS and/or CHIS outputs, and allocation of resources for CHIS further development. Further development of the model will be influenced by the next phase of this project: a survey of district and regional hospitals in two SA provinces. PMID:17911679

  13. A life course approach to injury prevention: a "lens and telescope" conceptual model

    PubMed Central

    2011-01-01

    Background Although life course epidemiology is increasingly employed to conceptualize the determinants of health, the implications of this approach for strategies to reduce the burden of injuries have received little recognition to date. Methods The authors reviewed core injury concepts and the principles of the life course approach. Based on this understanding, a conceptual model was developed, to provide a holistic view of the mechanisms that underlie the accumulation of injury risk and their consequences over the life course. Results A "lens and telescope" model is proposed that particularly draws on (a) the extended temporal dimension inherent in the life course approach, with links between exposures and outcomes that span many years, or even generations, and (b) an ecological perspective, according to which the contexts in which individuals live are critical, as are changes in those contexts over time. Conclusions By explicitly examining longer-term, intergenerational and ecological perspectives, life course concepts can inform and strengthen traditional approaches to injury prevention and control that have a strong focus on proximal factors. The model proposed also serves as a tool to identify intervention strategies that have co-benefits for other areas of health. PMID:21899775

  14. Studying the teaching of kindness: A conceptual model for evaluating kindness education programs in schools.

    PubMed

    Kaplan, Deanna M; deBlois, Madeleine; Dominguez, Violeta; Walsh, Michele E

    2016-10-01

    Recent research suggests that school-based kindness education programs may benefit the learning and social-emotional development of youth and may improve school climate and school safety outcomes. However, how and to what extent kindness education programming influences positive outcomes in schools is poorly understood, and such programs are difficult to evaluate in the absence of a conceptual model for studying their effectiveness. In partnership with Kind Campus, a widely adopted school-based kindness education program that uses a bottom-up program framework, a methodology called concept mapping was used to develop a conceptual model for evaluating school-based kindness education programs from the input of 123 middle school students and approximately 150 educators, school professionals, and academic scholars. From the basis of this model, recommendations for processes and outcomes that would be useful to assess in evaluations of kindness education programs are made, and areas where additional instrument development may be necessary are highlighted. The utility of the concept mapping method as an initial step in evaluating other grassroots or non-traditional educational programming is also discussed.

  15. Conceptualizing Programme Evaluation

    ERIC Educational Resources Information Center

    Hassan, Salochana

    2013-01-01

    The main thrust of this paper deals with the conceptualization of theory-driven evaluation pertaining to a tutor training programme. Conceptualization of evaluation, in this case, is an integration between a conceptualization model as well as a theoretical framework in the form of activity theory. Existing examples of frameworks of programme…

  16. Advancing an Information Model for Environmental Observations

    NASA Astrophysics Data System (ADS)

    Horsburgh, J. S.; Aufdenkampe, A. K.; Hooper, R. P.; Lehnert, K. A.; Schreuders, K.; Tarboton, D. G.; Valentine, D. W.; Zaslavsky, I.

    2011-12-01

    have been modified to support data management for the Critical Zone Observatories (CZOs). This paper will present limitations of the existing information model used by the CUAHSI HIS that have been uncovered through its deployment and use, as well as new advances to the information model, including: better representation of both in situ observations from field sensors and observations derived from environmental samples, extensibility in attributes used to describe observations, and observation provenance. These advances have been developed by the HIS team and the broader scientific community and will enable the information model to accommodate and better describe wider classes of environmental observations and to better meet the needs of the hydrologic science and CZO communities.

  17. Advances in Homology Protein Structure Modeling

    PubMed Central

    Xiang, Zhexin

    2007-01-01

    Homology modeling plays a central role in determining protein structure in the structural genomics project. The importance of homology modeling has been steadily increasing because of the large gap that exists between the overwhelming number of available protein sequences and experimentally solved protein structures, and also, more importantly, because of the increasing reliability and accuracy of the method. In fact, a protein sequence with over 30% identity to a known structure can often be predicted with an accuracy equivalent to a low-resolution X-ray structure. The recent advances in homology modeling, especially in detecting distant homologues, aligning sequences with template structures, modeling of loops and side chains, as well as detecting errors in a model, have contributed to reliable prediction of protein structure, which was not possible even several years ago. The ongoing efforts in solving protein structures, which can be time-consuming and often difficult, will continue to spur the development of a host of new computational methods that can fill in the gap and further contribute to understanding the relationship between protein structure and function. PMID:16787261

  18. Conceptual design of a self-deployable, high performance parabolic concentrator for advanced solar-dynamic power systems

    NASA Technical Reports Server (NTRS)

    Dehne, Hans Joachim; Duffy, Donald R.

    1989-01-01

    A summary is presented of the concentrator conceptual design work performed under a NASA-funded project. The design study centers around two basic efforts: conceptual design of a self-deploying, high-performance parabolic concentrator; and materials selection for a lightweight, shape-stable concentrator. The primary structural material selected for the concentrator is PEEK/carbon fiber composite. The deployment concept utilizes rigid gore-shaped reflective panels. The assembled concentrator takes a circular shape with a void in the center. The deployable solar concentrator concept is applicable to a range of solar dynamic power systems of 25 kWe to more than 75 kWe.

  19. Elements of a flexible approach for conceptual hydrological modeling: 2. Application and experimental insights

    NASA Astrophysics Data System (ADS)

    Kavetski, Dmitri; Fenicia, Fabrizio

    2011-11-01

    In this article's companion paper, flexible approaches for conceptual hydrological modeling at the catchment scale were motivated, and the SUPERFLEX framework, based on generic model components, was introduced. In this article, the SUPERFLEX framework and the "fixed structure" GR4H model (an hourly version of the popular GR4J model) are applied to four hydrologically distinct experimental catchments in Europe and New Zealand. The estimated models are scrutinized using several diagnostic measures, ranging from statistical metrics, such as the statistical reliability and precision of the predictive distribution of streamflow, to more process-oriented diagnostics based on flow-duration curves and the correspondence between model states and groundwater piezometers. Model performance was clearly catchment specific, with a single fixed structure unable to accommodate intercatchment differences in hydrological behavior, including seasonality and thresholds. This highlights an important limitation of any "fixed" model structure. In the experimental catchments, the ability of competing model hypotheses to reproduce hydrological signatures of interest could be interpreted on the basis of independent fieldwork insights. The potential of flexible frameworks such as SUPERFLEX is then examined with respect to systematic and stringent hypothesis-testing in hydrological modeling, for characterizing catchment diversity, and, more generally, for aiding progress toward a more unified formulation of hydrological theory at the catchment scale. When interpreted in physical process-oriented terms, the flexible approach can also serve as a language for dialogue between modeler and experimentalist, facilitating the understanding, representation, and interpretation of catchment behavior.

  20. Remotely sensed evapotranspiration to calibrate a lumped conceptual model: Pitfalls and opportunities

    NASA Astrophysics Data System (ADS)

    Willem Vervoort, R.; Miechels, Susannah F.; van Ogtrop, Floris F.; Guillaume, Joseph H. A.

    2014-11-01

    Physically representative hydrological models are essential for water resource management. New satellite evapotranspiration (ETobs) data might offer opportunities to improve model structure and parameter identifiability, if used as an independent calibration set. This study used a modelling experiment on 4 catchments in New South Wales, Australia, to investigate whether MODIS (16A3) ETobs can be used to improve parameter calibration for low parameter conceptual models. The catchment moisture deficit and exponential routing form of the model IHACRES was used to test calibration against streamflow, MODIS ETobs or a combination setoff the two. Results were compared against a regionalized parameter model and a model using MODIS ETobs directly as input. Firstly, the results indicated that the observed water balance of the catchments has, currently unexplained, large positive differences which impact the calibrated parameters. More generally, using MODIS ETobs as a calibration set, results in a reduction of the model performance as all residuals of the local water balance and timing differences between the water balance and the outflow need to be resolved by the routing component of the model. This is further complicated by variations in land cover affecting the MODIS ETobs. Finally this study confirms that the calibration of models using multiple environmental timeseries (such as MODIS ETobs and Q) can be used to identify structural model issues.